• 【食品加工行为的灵活表达:巴巴多斯野生加勒比gra脚扣篮率的决定因素。】 复制标题 收藏 收藏
    DOI:10.1016/j.beproc.2007.05.005 复制DOI
    作者列表:Morand-Ferron J,Lefebvre L
    BACKGROUND & AIMS: :Dunking, the softening of dry food in water to speed up consumption time, is normally a very rare behaviour in wild Carib grackles (Quiscalus lugubris) of Barbados. Its frequency can be experimentally increased when large numbers of dry items are repeatedly placed near a standing source of water in conditions that minimize intraspecific competition and risk of theft. To reconcile the normally low frequency of the behaviour in the wild with the high rates obtained in previous experiments, we tested three conditions where dunking varied between 0 and 70%. Dunking was very rare when it had been made unnecessary by pre-soaking the food, water was far from the dry items offered and only one food item was given, focusing all competitive interactions and theft attempts on a single individual. In contrast, dunking rate was high when food was not pre-soaked, water was close to dry food and more than one item (and hence target for competition and theft) was given. These experiments confirm that dunking rates, like other proto-tool-like food-processing techniques, depend on the costs and benefits of the situation where they are used.
    背景与目标: :灌水是软化干食品以加快消耗时间的水,通常在巴巴多斯的野生加勒比海gra(Quiscalus lugubris)中非常罕见。在将种内竞争和盗窃风险降至最低的条件下,将大量干燥物品反复放置在站立的水源附近时,可以通过实验提高其频率。为了使正常情况下野生动物行为的低频与先前实验中获得的高频率相一致,我们测试了3种情况,其中扣篮在0%到70%之间变化。当通过预先浸泡食物而使不必要的粪便稀少,水远离所提供的干粮时,仅提供一种粮食,所有竞争性互动和盗窃企图都集中在一个人身上。相比之下,当不预先浸泡食物时,扣篮率很高,水接近干粮,并且不止一项(因此成为竞争和盗窃的目标)。这些实验证实,与其他类似原型工具的食品加工技术一样,灌篮率取决于使用情况的成本和收益。
  • 【二尖瓣置换术后生存率和瓣膜衰竭的决定因素。】 复制标题 收藏 收藏
    DOI:10.1016/0003-4975(90)90316-x 复制DOI
    作者列表:Teoh KH,Ivanov J,Weisel RD
    BACKGROUND & AIMS: :A prospective evaluation of 333 consecutive patients undergoing isolated mitral valve replacement between 1982 and 1985 was performed to identify the predictors of survival and valve failure. Follow-up between 2 and 6 years postoperatively (mean, 32 +/- 17 months) was 98% complete. Four prostheses were inserted to permit a prospective evaluation of alternative valves: Björk-Shiley mechanical (n = 118), Ionescu-Shiley pericardial (n = 146), Carpentier-Edwards porcine (n = 38), and Hancock pericardial (n = 31). Hospital mortality was 6%, and actuarial survival at 5 years was 74% +/- 5%. Multivariate Cox regression analysis identified advancing age (less than 40 years, 88% +/- 7%; greater than 70 years, 50% +/- 14%) and poor left ventricular function (ejection fraction less than 0.20, 62% +/- 17%; ejection fraction greater than 0.60, 80% +/- 7%) as independent predictors of postoperative survival. Freedom from structural valve dysfunction, prosthetic valve endocarditis, reoperation, and valve-related mortality and morbidity were 86% +/- 4%, 91% +/- 4%, 81% +/- 4%, and 72% +/- 5%, respectively, at 5 years. The actuarial incidence of valve failure was inordinately high with the Hancock pericardial valve (p less than 0.05). Freedom from thromboembolic events (78% +/- 8% at 5 years) was significantly lower in patients with poor ventricular function (ejection fraction (less than 0.20, 54% +/- 20%; ejection fraction greater than 0.60, 73% +/- 11%; p less than 0.05). Survival after mitral valve replacement was determined by age and left ventricular function. Premature failure of the Hancock pericardial valve resulted in an unacceptable rate of valve-related complications.
    背景与目标: :对1982年至1985年间连续333例接受二尖瓣置换的患者进行了前瞻性评估,以确定生存率和瓣膜衰竭的预测因素。术后2至6年(平均32 /-17个月)的随访完成了98%。插入了四个假体,以对其他瓣膜进行前瞻性评估:Björk-Shiley机械式(n = 118),Ionescu-Shiley心包式(n = 146),Carpentier-Edwards猪(n = 38)和Hancock心包式(n = 31 )。医院死亡率为6%,5年的精算生存率为74%/-5%。多元Cox回归分析确定年龄提前(小于40岁,88%/-7%;大于70岁,50%/-14%)和左心室功能差(射血分数小于0.20,62%/-17%) ;射血分数大于0.60,80%/-7%)作为术后生存的独立预测指标。摆脱结构性瓣膜功能障碍,人工瓣膜心内膜炎,再次手术以及与瓣膜相关的死亡率和发病率分别为86%/-4%,91%/-4%,81%/-4%和72%/-5% ,在5年后。汉考克心包瓣膜的瓣膜衰竭的精算发生率异常高(p小于0.05)。心室功能不良的患者(射血分数(小于0.20,54%/-20%;射血分数大于0.60,73%/-11)时,无血栓栓塞事件(5年时为78%/-8%)显着降低%; p小于0.05)。二尖瓣置换术后的存活率由年龄和左心室功能决定,汉考克心包瓣膜过早衰竭导致瓣膜相关并发症的发生率不可接受。
  • 【2,3-二磷酸甘油酸和细胞内pH值是脱氧血红蛋白S生理溶解度的相互依赖的决定因素。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Poillon WN,Kim BC
    BACKGROUND & AIMS: :We have established that 2,3-diphosphoglycerate (2,3-DPG) content and intracellular pH exert separate, but interdependent, effects on the equilibrium solubility (csat) of deoxyhemoglobin S (deoxy-Hb S) that act in concert to modulate intraerythrocytic polymer formation. In a nonphysiologic csat assay system, a steep dependence of csat on pH in the physiologic range 7.0 to 7.6 was shown for both stripped (Hb) and DPG-saturated deoxy-Hb S (Hb-DPG). The solubility-pH profile for Hb under near-physiologic buffer conditions also showed that csat increased steeply in the same pH range (6.8 to 7.6). The effect of 2,3-DPG on csat under near-physiologic conditions was evaluated separately. At pH 7.20, the pH of the human red blood cell, csat values for Hb and Hb-DPG were 19.56 +/- 0.14 and 17.95 +/- 0.45 g/dL, respectively, indicating that the solubility of Hb-DPG is lower than that of Hb by 8.2% +/- 2.3%. Thus, binding of 2,3-DPG in the beta-cleft promotes the polymerization of deoxy-Hb S, the ultimate determinant of cell sickling. Furthermore, because of the abnormal Bohr effect of sickle blood (approximately double that of normal blood), the intracellular pH of deoxygenated sickle erythrocytes should be approximately 0.28 pH unit higher than that of oxygenated cells (ie, 7.41 v 7.13). At the higher pH, the corresponding csat for Hb-DPG is 20.22 g/dL, which is the best estimate of the intrinsic solubility of T-state Hb S under conditions that approximate closely those of pH, temperature, ionic strength, and 2,3-DPG saturation in the fully desaturated sickle erythrocyte.
    背景与目标: :我们已经确定2,3-二磷酸甘油酸(2,3-DPG)的含量和细胞内pH值对脱氧血红蛋白S(deoxy-Hb S)的平衡溶解度(csat)发挥了独立但相互依存的影响,这些作用共同调节红细胞内聚合物的形成。在非生理性csat分析系统中,对于汽提(Hb)和DPG饱和的脱氧Hb S(Hb-DPG),csat对pH值在7.0到7.6的生理范围内具有很强的依赖性。在接近生理缓冲液的条件下,Hb的溶解度-pH谱也显示csat在相同pH范围(6.8至7.6)下急剧增加。分别评估了2,3-DPG在近生理条件下对csat的影响。在pH 7.20时,人红细胞的pH,Hb和Hb-DPG的csat值分别为19.56 /-0.14和17.95 /-0.45 g / dL,表明Hb-DPG的溶解度低于Hb-DPG的溶解度。血红蛋白增加8.2%/-2.3%。因此,β-裂隙中2,3-DPG的结合促进了脱氧Hb S的聚合,脱氧Hb S是细胞镰刀的最终决定因素。此外,由于镰刀血具有异常的玻尔效应(大约是正常血液的两倍),脱氧的镰刀红细胞的细胞内pH值应比含氧细胞的细胞内pH值高约0.28 pH单位(即7.41 v 7.13)。在较高的pH值下,Hb-DPG的对应csat为20.22 g / dL,这是在接近pH,温度,离子强度和2的条件下,T型Hb S固有溶解度的最佳估计。完全去饱和的镰状红细胞中的3-DPG饱和。
  • 【凝血因子(F)IX水平正常变异的遗传决定因素:全基因组扫描和FIX结构基因检查。】 复制标题 收藏 收藏
    DOI:10.1111/j.1538-7836.2006.02024.x 复制DOI
    作者列表:Khachidze M,Buil A,Viel KR,Porter S,Warren D,Machiah DK,Soria JM,Souto JC,Ameri A,Lathrop M,Blangero J,Fontcuberta J,Warren ST,Almasy L,Howard TE
    BACKGROUND & AIMS: BACKGROUND:High-normal and elevated plasma FIX activity (FIX:C) levels are associated with increased risk for venous- and possibly arterial-thrombosis. OBJECTIVE:Because the broad normal range for FIX:C involves a substantial unknown genetic component, we sought to identify quantitative-trait loci (QTLs) for this medically important hemostasis trait. METHODS:We performed a genome-wide screen and a resequencing-based variation scan of the known functional regions of every distinct FIX gene (F9) in the genetic analysis of idiopathic thrombophilia project (GAIT), a collection of 398 Spanish-Caucasians from 21 pedigrees. RESULTS:We found no evidence for linkage (LOD scores <1.5) despite genotyping more than 540 uniformly-spaced microsatellites. We identified 27 candidate F9 polymorphisms, including three in cis-elements responsible for the increase in FIX:C that occurs with aging, but found no significant genotype-specific differences in mean FIX:C levels (P-values > or = 0.11) despite evaluating every polymorphism in GAIT by marginal multicovariate measured-genotype association analysis. CONCLUSIONS:The heritable component of interindividual FIX:C variability likely involves a collection of QTLs with modest effects that may reside in genes other than F9. Nevertheless, because the alleles of these 27 polymorphisms exhibited a low overall degree of linkage disequilibrium, we are currently defining their haplotypes to interrogate several highly-conserved non-exonic sequences and other F9 segments not examined here.
    背景与目标: 背景:血浆FIX活性(FIX:C)水平较高和较高与静脉血栓形成和可能的动脉血栓形成的风险增加有关。
    目的:由于FIX:C的广泛正常范围涉及大量未知的遗传成分,因此我们试图确定这种医学上重要的止血性状的定量性状基因座(QTL)。
    方法:在特发性血友病计划(GAIT)的遗传分析中,我们对每个不同的FIX基因(F9)的已知功能区进行了全基因组筛选和基于测序的变异扫描,该研究收集了来自21个国家的398名西班牙高加索人家谱。
    结果:尽管我们对540多个均匀分布的微卫星进行了基因分型,但我们没有发现连锁的证据(LOD得分<1.5)。我们确定了27个候选F9多态性,包括三个与衰老有关的FIX:C增加的顺式元素,但尽管平均FIX:C水平(P值>或= 0.11)没有发现明显的基因型特异性差异(尽管通过边缘多协变量测量基因型关联分析评估GAIT中的每个多态性。
    结论:个体FIX:C变异性的可遗传成分可能涉及具有适度作用的QTL集合,这些QTL可能存在于F9以外的基因中。但是,由于这27个多态性的等位基因表现出较低的整体连锁不平衡程度,因此我们目前正在定义其单倍型,以讯问几个高度保守的非外显子序列和此处未检查的其他F9片段。
  • 【肾下主动脉血栓量的测量和决定因素。】 复制标题 收藏 收藏
    DOI:10.1007/s00330-008-0956-3 复制DOI
    作者列表:Golledge J,Wolanski P,Parr A,Buttner P
    BACKGROUND & AIMS: :Intra-luminal thrombus has been suggested to play a role in the progression of abdominal aortic aneurysm (AAA). The aims of this study were twofold. Firstly, to assess the reproducibility of a computer tomography (CT)-based technique for measurement of aortic thrombus volume. Secondly, to examine the determinants of infrarenal aortic thrombus volume in a cohort of patients with aortic dilatation. A consecutive series of 75 patients assessed by CT angiography with maximum aortic diameter > or = 25 mm were recruited. Intra-luminal thrombus volume was measured by a semi-automated workstation protocol based on a previously defined technique to quantitate aortic calcification. Intra- and inter-observer reproducibility were assessed using correlation coefficients, coefficient of variation and Bland-Altman plots. Infrarenal aortic thrombus volume percentage was related to clinical, anatomical and blood characteristics of the patients using univariate and multivariate tests. Infrarenal aortic thrombus volume was related to the severity of aortic dilatation assessed by total aortic volume (r = 0.87, P < 0.0001) or maximum aortic diameter (r = 0.74, P < 0.0001). We therefore examined the clinical determinates of aortic thrombus expressed as a percentage of total aortic volume. Aortic thrombus percentage was negatively correlated with serum high density lipoprotein (HDL, r = -0.31). By ordinal multiple logistic regression analysis serum HDL below median (< or = 1.2 mM: ) was associated with aortic thrombus percentage in the upper quartile adjusting for other risk factors (odds ratio 5.3, 95% CI 1.1-25.0). Infrarenal aortic thrombus volume can be measured reproducibly on CT. Serum HDL, which can be therapeutically raised, may play a role in discouraging aortic thrombus accumulation with implications in terms of delaying progression of AAA.
    背景与目标: 提示腔内血栓在腹主动脉瘤(AAA)的进展中起作用。这项研究的目的是双重的。首先,评估基于计算机断层扫描(CT)的技术在测量主动脉血栓量方面的可重复性。其次,检查一群主动脉扩张患者的肾下主动脉血栓量的决定因素。连续征集了75例经CT血管造影评估为最大主动脉直径≥25 mm的患者。腔内血栓量是通过基于先前定义的定量主动脉钙化的技术的半自动化工作站方案进行测量的。使用相关系数,变异系数和Bland-Altman图评估观察者之间和观察者之间的可重复性。肾下主动脉血栓体积百分比与患者的临床,解剖学和血液特征有关,采用单因素和多因素测试。肾下主动脉血栓量与主动脉扩张的严重程度有关,后者通过总主动脉体积(r = 0.87,P <0.0001)或最大主动脉直径(r = 0.74,P <0.0001)评估。因此,我们检查了主动脉血栓的临床测定值,以总主动脉体积的百分比表示。主动脉血栓百分比与血清高密度脂蛋白呈负相关(HDL,r = -0.31)。通过序数logistic回归分析,血清HDL低于中位数(<或= 1.2 mM:)与上四分位的主动脉血栓百分比相关,并调整了其他危险因素(赔率比5.3,95%CI 1.1-25.0)。肾下主动脉血栓体积可在CT上重复测量。可以治疗性升高的血清HDL可能在阻止主动脉血栓积聚方面起作用,可能会延迟AAA的进展。
  • 【gag遗传决定因素对HIV-2感染患者加强洛匹那韦治疗后病毒学结果的影响。】 复制标题 收藏 收藏
    影响因子 :
    发表时间:2013-01-02
    来源期刊:AIDS
    DOI:10.1097/QAD.0b013e32835a10d8 复制DOI
    作者列表:Larrouy L,Vivot A,Charpentier C,Bénard A,Visseaux B,Damond F,Matheron S,Chene G,Brun-Vezinet F,Descamps D,ANRS CO5 HIV-2 Cohort.
    BACKGROUND & AIMS: OBJECTIVE:This study investigated the impact on virological outcome of the gag cleavage sites and the protease-coding region mutations in protease inhibitor-naive and protease inhibitor-experienced patients infected with HIV-2 receiving lopinavir (LPV) containing regimen. METHODS:Baseline gag and protease-coding region were sequenced in 46 HIV-2 group A-infected patients receiving lopinavir. Virological response was defined as plasma viral load less than 100 copies/ml at month 3. Associations between virological response and frequencies of mutations in gag [matrix/capsid (CA), CA/p2, p2/nucleocapsid (NC), NC/p1, p1/p6] and gag-pol (NC/p6) cleavage site and protease-coding region, with respect to the HIV-2ROD strain, were tested using Fisher's exact test. RESULTS:Virological response occurred in 14 of 17 (82%) protease inhibitor-naive and 17 of 29 (59%) protease inhibitor-experienced patients. Virological failure was associated with higher baseline viral load (median: 6765 versus 1098 copies/ml, P = 0.02). More protease-coding region mutations were observed in protease inhibitor-experienced compared with protease inhibitor-naive patients (median: 8 versus 5, P = 0.003). In protease inhibitor-naive patients, T435A (NC/p6), V447M (p1/p6), and Y14H (protease-coding region) were associated with virological failure (P = 0.011, P = 0.033, P = 0.022, respectively). T435A and V447M were associated with Y14H (P = 0.018, P = 0.039, respectively). In protease inhibitor-experienced patients, D427E (NC/p1) was associated with virological response (P = 0.014). A430V (NC/p1) and I82F (protease-coding region) were associated with virological failure (P = 0.046, P = 0.050, respectively). Mutations at position 430 were associated with a higher number of mutations in protease-coding region (median: 10 versus 7, P = 0.008). CONCLUSION:We have demonstrated, for the first time, an association between gag, gag-pol cleavage site and protease-coding region mutations, with distinct profiles between protease inhibitor-naive and protease inhibitor-experienced patients. These mutations might impact the virological outcome of HIV-2-infected patients receiving LPV-containing regimen.
    背景与目标: 目的:本研究调查了接受含洛匹那韦(LPV)治疗的HIV-2感染蛋白酶-2的未受蛋白酶抑制剂和经验丰富的蛋白酶抑制剂的患者对gag裂解位点的病毒学结果和蛋白酶编码区突变的影响。
    方法:对46名接受洛匹那韦的HIV-2 A组感染患者的基线gag和蛋白酶编码区进行测序。病毒学应答定义为在第3个月血浆病毒载量小于100拷贝/ ml。病毒学应答与gag突变频率之间的关联[基质/衣壳(CA),CA / p2,p2 /核衣壳(NC),NC / p1 ,p1 / p6]和gag-pol(NC / p6)切割位点和蛋白酶编码区,针对HIV-2ROD菌株,使用Fisher精确检验进行了测试。
    结果:病毒学应答发生在17例(82%)未使用蛋白酶抑制剂的患者中,有14例发生在29例(59%)使用蛋白酶抑制剂的患者中。病毒学衰竭与较高的基线病毒载量有关(中位数:6765对1098拷贝/ ml,P = 0.02)。与未使用蛋白酶抑制剂的患者相比,在有蛋白酶抑制剂经验的患者中观察到更多的蛋白酶编码区域突变(中位数:8对5,P = 0.003)。在未使用蛋白酶抑制剂的患者中,T435A(NC / p6),V447M(p1 / p6)和Y14H(蛋白酶编码区)与病毒学失败有关(分别为P = 0.011,P = 0.033,P = 0.022)。 T435A和V447M与Y14H相关(分别为P = 0.018,P = 0.039)。在有蛋白酶抑制剂经验的患者中,D427E(NC / p1)与病毒学应答有关(P = 0.014)。 A430V(NC / p1)和I82F(蛋白酶编码区)与病毒学失败有关(分别为P = 0.046,P = 0.050)。位置430的突变与蛋白酶编码区中更高数量的突变相关(中位数:10对7,P = 0.008)。
    结论:我们首次证明了gag,gag-pol切割位点和蛋白酶编码区突变之间的相关性,其中未使用蛋白酶抑制剂的患者和有蛋白酶抑制剂经验的患者之间存在明显的差异。这些突变可能会影响接受含LPV方案的HIV-2感染患者的病毒学结果。
  • 【韩国成年人中25(OH)D的状况以及25(OH)D的人口统计学和生活方式决定因素。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Choi EY
    BACKGROUND & AIMS: PURPOSE:Vitamin D deficiency is a global health problem that is associated with increased risks of major diseases. This study investigated the status of 25-hydroxyvitamin D [25(OH)D] and its demographic and lifestyle determinants among Korean adults. METHODS:A total of 5,847 adults who had participated in the Korean National Health and Nutrition Examination Survey of 2008 (KNHANES) were included in the present study. Stepwise linear regression analysis was performed to determine the demographic and lifestyle determinants of 25(OH)D concentration. RESULTS:The weighted prevalence (standard error) of 25(OH)D deficiency (<20 ng/mL) was 49.9 (2.1)% among the males and 67.4 (1.7)% among the females. Severe 25(OH)D deficiencies (<10 ng/mL) were found in 5.7 (0.8)% of the males and 11.1 (1.0)% of the females. These peaked in spring and winter. Only 12.2 (1.1)% of the males and 6.4 (0.6)% of the females exhibited 25(OH)D sufficiency (>=30 ng/mL). The correlates with higher 25(OH)D concentration for both genders included summer, fall (vs spring), the 60s age group (vs 20s), rural residence (vs urban), moderate and vigorous physical activity (vs sedentary), alcohol consumption, and multivitamin supplementation. Higher education and unmarried status were inversely associated with 25(OH)D concentration for both genders. The strongest predictors of 25(OH)D concentration were season and residential area. CONCLUSIONS:25(OH)D deficiency is a prevalent condition in Korea. Understanding the determinants of 25(OH)D can facilitate identification of persons at risk of 25(OH)D deficiency.
    背景与目标: 目的:维生素D缺乏症是一种全球性的健康问题,与重大疾病的风险增加有关。这项研究调查了韩国成年人中25-羟基维生素D [25(OH)D]的状况及其人口统计学和生活方式决定因素。
    方法:本研究共纳入了5847名参加了2008年韩国国家健康与营养检查调查(KNHANES)的成年人。进行逐步线性回归分析以确定25(OH)D浓度的人口统计学和生活方式决定因素。
    结果:25(OH)D缺乏症(<20 ng / mL)的加权患病率(标准误)在男性中为49.9(2.1)%,在女性中为67.4(1.7)%。在男性的5.7(0.8)%和女性的11.1(1.0)%中发现了严重的25(OH)D缺陷(<10 ng / mL)。这些在春季和冬季达到顶峰。男性中只有12.2(1.1)%的女性和6.4(0.6)%的女性具有25(OH)D充足性(> = 30 ng / mL)。男女之间较高的25(OH)D浓度相关,包括夏季,秋季(春季),60岁年龄段(20岁),农村居民(城市居民),中等强度和剧烈运动(久坐),饮酒和多种维生素补充剂。高等教育和未婚状况与男女的25(OH)D浓度成反比。 25(OH)D浓度的最强预测因子是季节和居住面积。
    结论:25(OH)D缺乏症在韩国很普遍。了解25(OH)D的决定因素可以帮助识别处于25(OH)D缺乏风险的人。
  • 【一些人喜欢它:蛋白质热稳定性的分子决定因素。】 复制标题 收藏 收藏
    DOI:10.1002/1439-7633(20020104)3:1<39::AID-CBIC39>3.0. 复制DOI
    作者列表:Perl D,Schmid FX
    BACKGROUND & AIMS: -2
    背景与目标: -2
  • 【单个神经元对听觉中脑振幅调制的基本反应决定因素。】 复制标题 收藏 收藏
    DOI:10.1007/s002210000461 复制DOI
    作者列表:Chiu TW,Poon PW
    BACKGROUND & AIMS: :Amplitude-modulated (AM) signals represent important components of environmental sounds. While single-cell responses to AM tones in the central auditory system were often studied using repetitive modulation, owing to its presence in vocalization signals, the AM response has not been fully depicted in terms of receptive field in the stimulus domain. This study was aimed to characterize the receptive field of AM response with respect to nonrepetitive AM stimuli and to understand how complex acoustic signals may be coded in the brain. A novel AM stimulus was implemented with a random envelope and a systemic change in intensity across trials. From 393 single units recorded in the inferior colliculus (IC) of urethane-anesthetized rats, responses to the AM stimulus were first characterized in terms of dot-raster pattern. Three types of response were identified: type I showing a monotonic response to mainly the steady states of the AM envelope and type II to rising phases of the AM envelope with a clear intensity preference. Type III showed a mixed response of both type I and type II. A small number of units, called type IV, responded to both rising and falling phases of the modulation. Using perispike averaging, the AM receptive field, or "level temporal receptive field" (LTRF), was displayed in a "stimulus level versus perispike time" plane. The LTRF, particularly of the type II response, clearly revealed triggering features of the cell. The triggering features are consistent with the representation of the cell's response in a receptive space formed by the Cartesian axes of the velocity of amplitude modulation, the intensity of the sound, and the range of modulation. We therefore considered these stimulus parameters as the three basic determinants of the AM response in the auditory midbrain.
    背景与目标: :调幅(AM)信号代表环境声音的重要组成部分。尽管经常使用重复调制来研究中央听觉系统对AM音调的单细胞响应,由于其在发声信号中存在,但AM响应在刺激域的感受野方面尚未得到完整描述。这项研究旨在表征与非重复性AM刺激有关的AM反应的感受野,并了解如何在大脑中编码复杂的声音信号。实施了新型AM刺激,其随机包络和整个试验期间强度的系统性改变。从氨基甲酸乙酯麻醉大鼠下丘脑(IC)中记录的393个单位中,首先根据点阵模式表征了对AM刺激的反应。确定了三种类型的响应:I型对AM包络的稳态表现出单调响应,II型对AM包络的上升阶段具有明显的强度偏好。 III型表现出I型和II型的混合反应。少量的单元(称为IV型)对调制的上升阶段和下降阶段都做出了响应。使用峰峰值平均,在“刺激水平与峰峰值时间”平面中显示AM感受野或“水平时间感受野”(LTRF)。 LTRF(特别是II型反应)清楚地揭示了细胞的触发特征。触发特征与由振幅调制速度,声音强度和调制范围的直角坐标轴形成的接收空间中细胞响应的表示一致。因此,我们认为这些刺激参数是听觉中脑AM反应的三个基本决定因素。
  • 【学徒中IgE介导的致敏的发生率和决定因素。前瞻性研究。】 复制标题 收藏 收藏
    DOI:10.1164/ajrccm.162.4.2001023 复制DOI
    作者列表:Gautrin D,Ghezzo H,Infante-Rivard C,Malo JL
    BACKGROUND & AIMS: :We investigated prospectively the incidence and determinants of work-related specific skin sensitization in a cohort of 769 apprentices, including 417 in animal health technology, 230 in pastry-making, and 122 in dental-hygiene technology. Subjects were recruited when starting exposure to laboratory animals, flour, or latex. A questionnaire and skin-prick tests with common and work-related allergens were administered on entry and at follow-up visits from 8 to 44 mo; information on number of hours of exposure to specific allergens was obtained. Among 769 apprentices, 698 attended >/= 1 follow-up visit. A total of 111 subjects developed specific sensitization over the study period. The incidence of work-related sensitization (per person-year) was 8.9% (95% CI 7.3 to 11.0%) in the animal-health program, 4.2% (95% CI 1.8 to 8.2%) in the pastry-making program, and 2.5% (95% CI = 0.7 to 4.3%) in the dental-hygiene program. In the animal health group, Cox regression analyses showed that atopy, nasal, and respiratory symptoms in the pollen season, and exposure assessed by the school attended or by duration of exposure to rodents were the most significant predictors of sensitization. In the dental-hygiene program, atopy and asthma were significant determinants. This study shows that: (1) an apprenticeship in animal-health technology carries a greater risk of developing specific sensitization than do apprenticeships in pastry-making and dental-hygiene; (2) atopy, respiratory symptoms in the pollen season, and number of hours in contact with rodents determine the risk of sensitization in apprentices in the animal health program.
    背景与目标: :我们前瞻性地调查了769名学徒的工作相关的特定皮肤致敏性的发生率和决定因素,其中包括动物卫生技术领域的417名,糕点制造领域的230名和牙齿卫生技术领域的122名。开始接触实验动物,面粉或乳胶时招募受试者。在入院时和随访时(从8个月到44个月)进行了问卷调查和针对常见和与工作有关的过敏原的皮肤点刺试验;获得有关暴露于特定变应原的小时数的信息。在769名学徒中,有698名参加了> / = 1次随访。在研究期间,共有111名受试者出现了特定的致敏作用。在动物健康计划中,与工作相关的敏感性发生率(每人年)为8.9%(95%CI 7.3至11.0%),在糕点制作计划中为4.2%(95%CI 1.8至8.2%),而在牙齿卫生计划中占2.5%(95%CI = 0.7至4.3%)。在动物健康组中,Cox回归分析表明,在花粉季节中的过敏性,鼻和呼吸道症状以及学校就读或啮齿动物接触时间所评估的接触是致敏性的最重要预测因子。在牙齿卫生计划中,特应性疾病和哮喘是重要的决定因素。这项研究表明:(1)与糕点制作和牙齿卫生学徒制相比,动物卫生技术学徒制产生特定致敏性的风险更大; (2)过敏性疾病,花粉季节的呼吸道症状以及与啮齿动物接触的小时数决定了动物保健计划中学徒致敏的风险。
  • 【埃塞俄比亚5岁以下儿童营养状况的决定因素:2016年埃塞俄比亚人口与健康调查的进一步分析。】 复制标题 收藏 收藏
    DOI:10.1186/s12992-019-0505-7 复制DOI
    作者列表:Amare ZY,Ahmed ME,Mehari AB
    BACKGROUND & AIMS: BACKGROUND:The aim of this study was to examine the determinants of nutritional status among children under age 5 (0-59 months) in Ethiopia. Child malnutrition is an underlying cause of almost half (45%) of child deaths, particularly in low socioeconomic communities of developing countries. In Ethiopia, the prevalence of stunting decreased from 47% in 2005 to 39% in 2016, but the prevalence of wasting changed little over the same time period (from 11 to 10%). Despite improvements in reducing the prevalence of malnutrition, the current rate of progress is not fast enough to reach the World Health Organization global target for reducing malnutrition 40% by 2025. METHODS:This study used data from the 2016 Ethiopia Demographic and Heath Survey (EDHS). The analysis used stunting and wasting as dependent variables, while the independent variables were characteristics of children, mothers, and households. Logistic regression was used to analyze the determinants of nutritional status among children. Bivariate analysis was also used to analyze the association between the dependent and independent variables. RESULTS:Study results show that child's age, sex, and perceived birth weight, mother's educational status, body mass index (BMI), and maternal stature, region, wealth quintile, type of toilet facility, and type of cooking fuel had significant associations with stunting. Child's age, sex, and perceived birth weight, mother's BMI, and residence and region showed significant associations with wasting. The study found that child, maternal, and household characteristics were significantly associated with stunting and wasting among children under age 5. CONCLUSION:These findings imply that a multi-sectorial and multidimensional approach is important to address malnutrition in Ethiopia. The education sector should promote reduction of cultural and gender barriers that contribute to childhood malnutrition. The health sector should encourage positive behaviors toward childcare and infant feeding practices. More should be done to help households adopt improved types of toilet facilities and modern types of cooking fuels.
    背景与目标: 摘要背景:这项研究的目的是检查埃塞俄比亚5岁以下儿童(0-59个月)的营养状况决定因素。儿童营养不良是几乎一半(45%)儿童死亡的根本原因,特别是在发展中国家的社会经济地位低下的国家。在埃塞俄比亚,发育迟缓的患病率从2005年的47%下降到2016年的39%,但同一时期的浪费发生率变化不大(从11%降至10%)。尽管减少营养不良的发生率有所改善,但目前的进展速度还不足以达到世界卫生组织的全球目标,即到2025年将营养不良减少40%。
    方法:本研究使用了2016年埃塞俄比亚人口与健康调查(EDHS)的数据。分析使用发育迟缓和消瘦作为因变量,而自变量是儿童,母亲和家庭的特征。使用Logistic回归分析儿童营养状况的决定因素。双变量分析还用于分析因变量和自变量之间的关联。
    结果:研究结果表明,孩子的年龄,性别和可感知的出生体重,母亲的教育程度,体重指数(BMI)以及母亲的身材,地区,五分之一的财富,洗手间的类型和烹饪燃料的类型与发育迟缓。儿童的年龄,性别,可感知的出生体重,母亲的BMI,居住地和地区与消瘦显着相关。研究发现,儿童,孕产妇和家庭特征与5岁以下儿童的发育迟缓和消瘦显着相关。
    结论:这些发现表明,多部门,多层面的方法对于解决埃塞俄比亚的营养不良具有重要意义。教育部门应促进减少造成儿童营养不良的文化和性别障碍。卫生部门应鼓励儿童保育和婴儿喂养行为方面的积极行为。应该做更多的工作来帮助家庭采用改进的厕所设施和现代的烹调燃料。
  • 【寻找人类神经管缺陷的遗传决定因素。】 复制标题 收藏 收藏
    DOI:10.1097/MOP.0000000000000817 复制DOI
    作者列表:Wolujewicz P,Ross ME
    BACKGROUND & AIMS: PURPOSE OF REVIEW:An update is presented regarding neural tube defects (NTDs) including spina bifida and anencephaly, which are among the most common serious birth defects world-wide. Decades of research suggest that no single factor is responsible for neurulation failure, but rather NTDs arise from a complex interplay of disrupted gene regulatory networks, environmental influences and epigenetic regulation. A comprehensive understanding of these dynamics is critical to advance NTD research and prevention. RECENT FINDINGS:Next-generation sequencing has ushered in a new era of genomic insight toward NTD pathophysiology, implicating novel gene associations with human NTD risk. Ongoing research is moving from a candidate gene approach toward genome-wide, systems-based investigations that are starting to uncover genetic and epigenetic complexities that underlie NTD manifestation. SUMMARY:Neural tube closure is critical for the formation of the human brain and spinal cord. Broader, more all-inclusive perspectives are emerging to identify the genetic determinants of human NTDs.
    背景与目标: 审查目的:提供有关神经管畸形(NTD)的更新,包括脊柱裂和无脑畸形,它们是全世界最常见的严重先天性畸形之一。数十年的研究表明,没有单个因素可导致神经功能衰竭,而NTD则是由基因调控网络破坏,环境影响和表观遗传调控的复杂相互作用所引起的。全面了解这些动态因素对于推进NTD研究和预防至关重要。
    最近的发现:下一代测序技术已经进入了对NTD病理生理学的基因组学研究的新时代,这暗示了与人类NTD风险相关的新型基因。正在进行的研究正从候选基因方法转向全基因组,基于系统的研究,这些研究开始发现构成NTD表现基础的遗传和表观遗传学复杂性。
    摘要:神经管闭合对于人脑和脊髓的形成至关重要。正在出现更广泛,更包容各方的观点,以鉴定人类NTD的遗传决定因素。
  • 【幼鹦鹉鱼(Chlorurus sordidus)的生理颜色模式的决定因素】 复制标题 收藏 收藏
    DOI:10.1006/anbe.1996.0444 复制DOI
    作者列表:Crook AC
    BACKGROUND & AIMS: Field observations of the different physiological colour patterns (PCPs) of juvenile bullethead parrotfish, Chlorurus sordiduswere conducted at three sites around Lizard Island, Australia. The aim of the study was to quantify, using log-linear analysis, the influence of simultaneously interacting variables upon the PCPs shown by this species in the field. It was proposed that features of an individual, such as body size (total length) and schooling behaviour (schooling/not schooling), as well as foraging activity (feeding/not feeding), were influential in PCP determination. In addition, the influence of time of day was considered. Overall, an individual's body size was the most significant factor, being over six times more important than foraging activity in determining the PCP displayed. The schooling behaviour of an individual was 40% more important than foraging activity in PCP determination. Furthermore, the correlation between body size and PCP was itself dependent on time of day whilst both foraging activity and schooling behaviour were independent of time of day. The systematic methodology used enabled interactions between variables to be ranked numerically and their biological significance to be discussed. The results present correlational evidence that PCPs may function for anti-predator purposes and provide the basis for future studies into the function of PCPs in juvenile C. sordidus

    背景与目标: 在澳大利亚蜥蜴岛周围的三个地点进行了对幼年子弹头鹦嘴鱼Chlorurus sordidus的不同生理颜色图案(PCP)的现场观察。该研究的目的是使用对数线性分析来量化同时相互作用的变量对该物种在野外显示的五氯苯酚的影响。有人提出,个人特征,例如身材(总长)和上学行为(上学/不上学)以及觅食活动(进食/不进食),对五氯苯酚的测定有影响。另外,考虑了一天中时间的影响。总体而言,个人的身材是最重要的因素,在确定所显示的PCP方面比觅食活动重要六倍以上。在确定PCP方面,个人的学习行为比觅食活动重要40%。此外,体型与PCP之间的相关性本身取决于一天中的时间,而觅食活动和学习行为均与一天中的时间无关。使用的系统方法论使变量之间的相互作用能够进行数值排名,并对其生物学意义进行讨论。结果提供了相关证据,证明五氯苯酚可能起到反捕食目的,并为今后研究幼小梭状芽胞杆菌的五氯苯酚的功能提供了依据。

  • 【急性缺血性卒中门到针时间延长的决定因素及其对医院内死亡率的影响:荷兰全国临床审核的结果。】 复制标题 收藏 收藏
    DOI:10.1186/s12883-019-1512-2 复制DOI
    作者列表:Kuhrij LS,Marang-van de Mheen PJ,van den Berg-Vos RM,de Leeuw FE,Nederkoorn PJ,Dutch Acute Stroke Audit consortium.
    BACKGROUND & AIMS: BACKGROUND:Intravenous thrombolysis (IVT) plays a prominent role in the treatment of acute ischemic stroke (AIS). The sooner IVT is administered, the higher the odds of a good outcome. Therefore, registering the in-hospital time to treatment with IVT, i.e. the door-to-needle time (DNT), is a powerful way to measure quality improvement. The aim of this study was to identify determinants that are associated with extended DNT. METHODS:Patients receiving IVT in 2015 and 2016 registered in the Dutch Acute Stroke Audit were included. DNT and onset-to-door time (ODT) were dichotomized using the median (i.e. extended DNT) and the 90th percentile (i.e. severely extended DNT). Logistic regression was performed to identify determinants associated with (severely) extended DNT/ODT and its effect on in-hospital mortality. A linear model with natural spline was used to investigate the association between ODT and DNT. RESULTS:Included were 9518 IVT treated patients from 75 hospitals. Median DNT was 26 min (IQR 20-37). Determinants associated with a higher likelihood of extended DNT were female sex (OR 1.17, 95% CI 1.05-1.31) and admission during off-hours (OR 1.12, 95% CI 1.01-1.25). Short ODT correlated with longer DNT, whereas longer ODT correlated with shorter DNT. Young age (OR 1.38, 95% CI 1.07-1.76) and admission to a comprehensive stroke center (OR 1.26, 1.10-1.45) were associated with severely extended DNT, which was associated with in-hospital mortality (OR 1.54, 95%CI 1.19-1.98). CONCLUSIONS:Even though DNT in the Netherlands is short compared to other countries, lowering the DNT may be achievable by focusing on specific subgroups.
    背景与目标: 背景:静脉溶栓(IVT)在急性缺血性中风(AIS)的治疗中起着重要的作用。 IVT越早施行,取得良好结果的几率越高。因此,记录住院时间以IVT治疗,即门到针时间(DNT),是衡量质量改善的有效方法。这项研究的目的是确定与扩展DNT相关的决定因素。
    方法:纳入2015年和2016年在荷兰急性卒中审核中注册的IVT患者。使用中位数(即扩展的DNT)和第90个百分位数(即,严重扩展的DNT)将DNT和开始上门时间(ODT)二分。进行逻辑回归分析以确定与(严重)延长的DNT / ODT相关的决定因素及其对医院内死亡率的影响。使用带有自然样条的线性模型来研究ODT和DNT之间的关联。
    结果:包括来自75家医院的9518 IVT治疗的患者。 DNT中位数为26分钟(IQR 20-37)。与延长DNT可能性更高相关的决定因素是女性(OR 1.17,95%CI 1.05-1.31)和下班时间入院(OR 1.12,95%CI 1.01-1.25)。较短的ODT与较长的DNT相关,而较长的ODT与较短的DNT相关。年轻(OR 1.38,95%CI 1.07-1.76)和进入综合性卒中中心(OR 1.26,1.10-1.45)与DNT严重延长有关,而DNT与医院内死亡率相关(OR 1.54,95%CI) 1.19-1.98)。
    结论:尽管荷兰的DNT较其他国家短,但通过关注特定的亚组可以降低DNT。
  • 【在温哥华流行期间,注射吸毒者中HIV血清转变的决定因素。】 复制标题 收藏 收藏
    DOI:10.1258/0956462971920497 复制DOI
    作者列表:Patrick DM,Strathdee SA,Archibald CP,Ofner M,Craib KJ,Cornelisse PG,Schechter MT,Rekart ML,O'Shaughnessy MV
    BACKGROUND & AIMS: :To identify determinants of HIV seroconversion among injection drug users (IDUs) during a period of rising prevalence, a case-control investigation was conducted. Cases were IDUs with a new positive test after 1 January 1994, and a negative test within the prior 18 months. Controls required 2 negative tests during the same period. Subjects completed a questionnaire on demographic, psychosocial, and behavioural factors. Eighty-nine cases and 192 controls were similar with respect to gender, age, ethnicity and inter-test interval. Multivariate analyses of events during the inter-test interval showed borrowing syringes (adj. OR = 2.96; P < 0.006), unstable housing (adj. OR = 2.01; P = 0.03) and injecting > or = 4 times daily (adj. OR = 1.71; P = 0.06) to be independently associated with seroconversion. Protective associations were demonstrated for sex with opposite gender (adj. OR = 0.36; P = 0.001) and tetrahydrocannabinol use (adj. OR = 0.41; P = 0.001). There is a need to evaluate programmes dealing with addiction, housing and the social underpinnings of risk behaviours in this population.
    背景与目标: :为了确定在流行率上升期间注射吸毒者(IDU)中HIV血清转变的决定因素,进行了病例对照研究。病例是注射吸毒者,在1994年1月1日之后进行了新的阳性测试,在之前的18个月内进行了阴性测试。对照在同一时期需要2次阴性测试。受试者完成了有关人口,社会心理和行为因素的问卷调查。在性别,年龄,种族和测试间隔方面,有89例病例和192名对照者相似。测试间隔期间事件的多变量分析显示,借用注射器(调整OR = 2.96; P <0.006),不稳定的外壳(调整OR = 2.01; P = 0.03)并且每天注入>或= 4次(调整OR) = 1.71; P = 0.06)与血清转化无关。已证明对异性有保护性关联(调整OR = 0.36; P = 0.001)和使用四氢大麻酚(调整OR = 0.41; P = 0.001)。需要评估有关该人群的成瘾,住房和风险行为的社会基础的计划。

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