• 【估计在美国销售的烈酒,葡萄酒和啤酒的平均酒精浓度和人均消费量: 1950 2002年。】 复制标题 收藏 收藏
    DOI:10.1111/j.1530-0277.2006.00190.x 复制DOI
    作者列表:Kerr WC,Greenfield TK,Tujague J
    BACKGROUND & AIMS: BACKGROUND:Estimates of per capita consumption of alcohol in the United States require estimates of the mean alcohol content by volume (%ABV) of the beer, wine, and spirits sold to convert beverage volume to gallons of pure alcohol. METHODS:The mean %ABV of spirits is estimated for each year from 1950 to 2002 and for each state using the %ABV of major brands and sales of sprits types. The mean %ABV of beer and wine is extrapolated to cover this period based on previous estimates. These mean %ABVs are then applied to alcohol sales figures to calculate new yearly estimates of per capita consumption of beer, wine, spirits, and total alcohol for the United States population aged 15 and older. RESULTS:The mean %ABV for spirits is found to be lower than previous estimates and to vary considerably over time and across states. Resultant per capita consumption estimates indicate that more alcohol was consumed from beer and less from wine and spirits than found in previous estimates. CONCLUSIONS:Empirically based calculation of mean %ABV for beer, wine, and spirits sold in the United States results in different and presumably more accurate per capita consumption estimates than heretofore available. Utilization of the new estimates in aggregate time-series and cross-sectional models of alcohol consumption and related outcomes may improve the accuracy and precision of such models.
    背景与目标:
  • 【围产期B组链球菌病发病率的降低-美国,1993-1995。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Centers for Disease Control and Prevention (CDC).
    BACKGROUND & AIMS: :Group B streptococcal (GBS) infections are the leading cause of bacterial disease and death among newborns in the United States and an important cause of morbidity among peripartum women and nonpregnant adults with chronic medical conditions. Disease in infants usually presents as sepsis, pneumonia or meningitis but also may include cellulitis or osteomyelitis. In 1990, GBS infections caused an estimated 7600 serious illnesses and 310 deaths among U.S. infants aged < or = 90 days; infections among infants aged < 7 days (i.e., early-onset disease) accounted for approximately 80% of these illnesses. To determine the incidence of GBS disease during 1993-1995, CDC conducted surveillance for this disease in an aggregate population of 12.5 million persons with 190,000 annual live-born infants. This report summarizes the findings of surveillance in this population, which indicate that a statistically significant decline in the incidence of early-onset GBS disease occurred in some surveillance areas.
    背景与目标: : B组链球菌 (GBS) 感染是美国新生儿细菌性疾病和死亡的主要原因,也是围产期妇女和患有慢性疾病的未怀孕成年人发病的重要原因。婴儿的疾病通常表现为败血症,肺炎或脑膜炎,但也可能包括蜂窝织炎或骨髓炎。1990年,GBS感染在 <或 = 90天的美国婴儿中导致估计7600种严重疾病和310例死亡; <7天的婴儿 (即早发疾病) 感染约占这些疾病的80%。为了确定1993-1995年期间GBS疾病的发生率,CDC对1250万名每年有190,000名活产婴儿的人群进行了该疾病的监测。该报告总结了该人群的监测结果,这表明在某些监测地区,早发性GBS疾病的发病率在统计学上显着下降。
  • 【美国风疹和先天性风疹综合征的流行病学概况,1998-2004: 缺乏地方性传播的证据。】 复制标题 收藏 收藏
    DOI:10.1086/505944 复制DOI
    作者列表:Reef SE,Redd SB,Abernathy E,Zimmerman L,Icenogle JP
    BACKGROUND & AIMS: :In 1969, the United States established its national rubella vaccination program. With the success of the program, 32 years later, reports of rubella reached record low numbers. To assess the achievement of elimination of rubella and congenital rubella syndrome (CRS) in the United States, 7 epidemiological criteria were used. Rubella cases reported to the National Notifiable Diseases Surveillance System from 1998 through 2004 and CRS cases reported to the National Congenital Rubella Syndrome Registry from 1998 through 2004 were analyzed. During 1998-2000, the median number of reported rubella cases was 272, whereas, during 2001-2004, the median number reported was 13. The incidence of rubella decreased significantly, from 0.1/100,000 population in 1998 to 0.005/100,000 population in 2004. Since 2001, 5 infants with CRS have been reported--3 were born in 2001, 1 was born in 2003, and 1 was born in 2004. The epidemiological evidence strongly supports the claim that rubella is no longer endemic in the United States. To prevent future rubella outbreaks and CRS cases, current strategies must be maintained.
    背景与目标: : 1969年,美国建立了国家风疹疫苗接种计划。随着该计划的成功,32年后,风疹的报道达到了历史新低。为了评估在美国消除风疹和先天性风疹综合征 (CRS) 的成就,使用了7个流行病学标准。分析了向国家法定疾病监测系统报告的风疹病例1998年2004年和向国家先天性风疹综合征登记1998年2004年报告的CRS病例。在1998-2000年期间,报告的风疹病例的中位数为272,而在2001-2004年期间,报告的中位数为13。风疹的发病率从0.1/100,000人口1998年下降到0.005/100,000人口2004年。自2001年以来,已报告5例CRS婴儿-3例2001年出生,1例2003年出生,1例2004年出生。流行病学证据强烈支持风疹在美国不再流行的说法。为了防止未来的风疹暴发和CRS病例,必须维持当前的策略。
  • 【美国年轻人的健康状况。】 复制标题 收藏 收藏
    DOI:10.1016/j.jadohealth.2006.04.017 复制DOI
    作者列表:Park MJ,Paul Mulye T,Adams SH,Brindis CD,Irwin CE Jr
    BACKGROUND & AIMS: :The health issues of young adulthood have received relatively little attention compared with those of adolescence, although the critical issues in young adulthood parallel those of adolescence. Young adults often fare worse than adolescents on health indicators, with many measures of negative outcomes--including rates of injury, homicide, and substance use--peaking during the young adult years. The contextual factors shaping health status and access to care in young adulthood differ significantly from the context of adolescence. This article synthesizes national data to present a health profile of young adults, reviewing social indicators that describe the context of young adulthood and presenting measures of health status. We examine mortality, morbidity, risky behaviors, and health care access and utilization, identifying the most significant gender and racial/ethnic disparities. The article also identifies limitations of existing data and offers suggestions for future research and health monitoring in this area. We conclude with a discussion of current efforts to address the health and well-being of young adults and argue for creating a national health agenda for young adults that includes research, programs and policies to address health issues during this period of the lifespan.
    背景与目标: : 与青春期相比,成年后的健康问题受到的关注相对较少,尽管成年后的关键问题与青春期的问题平行。在健康指标上,年轻人的表现通常比青少年差,许多负面结果指标 (包括受伤,凶杀和吸毒的发生率) 在年轻人时期达到顶峰。影响成年后健康状况和获得护理的背景因素与青春期的背景有很大不同。本文综合了国家数据,以提供年轻人的健康状况,回顾了描述年轻人成年背景的社会指标,并提出了健康状况的衡量标准。我们检查了死亡率,发病率,危险行为以及医疗保健的获取和利用情况,以确定最重要的性别和种族/种族差异。本文还指出了现有数据的局限性,并为该领域的未来研究和健康监测提供了建议。最后,我们讨论了当前为解决年轻人的健康和福祉所做的努力,并主张为年轻人制定国家健康议程,其中包括研究,计划和政策,以解决这一生命周期中的健康问题。
  • 【儿科武术损伤呈现给急诊科,美国1990-2003。】 复制标题 收藏 收藏
    DOI:10.1016/j.jsams.2006.06.016 复制DOI
    作者列表:Yard EE,Knox CL,Smith GA,Comstock RD
    BACKGROUND & AIMS: :Although an estimated 6.5 million United States (US) children aged 6-17 practiced a martial art in 2004, there have been no nationally representative studies comparing pediatric injuries among the three most popular disciplines, karate, taekwondo, and judo. Describe pediatric martial arts injuries presenting to a representative sample of US Emergency Departments (EDs) from 1990 to 2003. We reviewed all martial arts injuries captured by the US Consumer Product Safety Commission's (CPSC), National Electronic Injury Surveillance System (NEISS). An estimated 128,400 children
    背景与目标: : 尽管估计有650万名6-17岁的美国儿童练习武术2004年,但尚无全国性的研究比较空手道,跆拳道和柔道这三个最受欢迎的学科中的小儿伤害。向美国急诊科 (EDs) 1990年2003年的代表性样本介绍小儿武术损伤。我们回顾了美国消费者产品安全委员会 (CPSC),国家电子伤害监视系统 (NEISS) 捕获的所有武术伤害。在美国EDs中,估计有128,400名
  • 【英国肾移植资源评估。】 复制标题 收藏 收藏
    DOI:10.1016/s0140-6736(85)91508-9 复制DOI
    作者列表:Sells RA,Macpherson S,Salaman JR
    BACKGROUND & AIMS: :Statistics on treatment rates for patients with end stage renal disease (ESRD) show that the number of ESRD patients per million population in the United Kingdom has increased slowly in recent years. The British Transplantation Society issued questionnaires in 1983 and 1984 to determine the number of patients transplanted, the number of suitable patients, and the facilities needed to enable all suitable patients to receive treatment. While there is a high transplant rate, the percentage of ESRD patients on dialysis is low, and there is a "socially unacceptable deficit" with respect to treatment of diabetics and the elderly.
    背景与目标: : 有关终末期肾病 (ESRD) 患者治疗率的统计数据表明,英国每百万人口中ESRD患者的数量近年来增长缓慢。英国移植学会1983年和1984发放了问卷,以确定移植的患者人数、合适的患者人数以及使所有合适的患者都能接受治疗所需的设施。尽管移植率很高,但接受透析的ESRD患者的百分比却很低,并且在糖尿病患者和老年人的治疗方面存在 “社会上不可接受的缺陷”。
  • 【生命体征: 美国年轻人中的HIV感染,检测和危险行为。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Centers for Disease Control and Prevention (CDC).
    BACKGROUND & AIMS: BACKGROUND:In 2009, 6.7% of the estimated 1.1 million persons living with human immunodeficiency virus (HIV) infection in the United States were youths (defined in this report as persons aged 13-24 years); more than half of youths with HIV (59.5%) were unaware of their infection. METHODS:CDC used National HIV Surveillance System data to estimate, among youths, prevalence rates of diagnosed HIV infection in 2009 and the number of new infections (incidence) in 2010. To assess the prevalence of risk factors and HIV testing among youths, CDC used the 2009 and 2011 Youth Risk Behavior Surveillance System for 9th-12th grade students and the 2010 National Health Interview Survey (NHIS) for persons 18-24 years. RESULTS:Prevalence of diagnosed HIV was 69.5 per 100,000 youths at the end of 2009. Youths accounted for 12,200 (25.7%) new HIV infections in 2010. Of these, 7,000 (57.4%) were among blacks/African Americans, 2,390 (19.6%) among Hispanics/Latinos, and 2,380 (19.5%) among whites; 8,800 (72.1%) were attributed to male-to-male sexual contact. The percentage of youths tested for HIV overall was 12.9% among high school students and 34.5% among those aged 18-24 years; it was lower among males than females, and lower among whites and Hispanics/Latinos than blacks/African Americans. CONCLUSIONS:A disproportionate number of new HIV infections occurs among youths, especially blacks/African Americans, Hispanics/Latinos, and men who have sex with men (MSM). The percentage of youths tested for HIV, however, was low, particularly among males. Implications for Public Health: More effort is needed to provide effective school- and community-based interventions to ensure all youths, particularly MSM, have the knowledge, skills, resources, and support necessary to avoid HIV infection. Health-care providers and public health agencies should ensure that youths are tested for HIV and have access to sexual health services, and that HIV-positive youths receive ongoing health-care and prevention services.
    背景与目标:
  • 【认为需要改变来自欧盟所有成员国的代表性成年人样本的饮食习惯。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Kearney M,Gibney MJ,Martinez JA,de Almeida MD,Friebe D,Zunft HJ,Widhalm K,Kearney JM
    BACKGROUND & AIMS: OBJECTIVE:To examine the perceived need to alter eating habits among nationally-representative samples from each member state of the European Union (EU).

    DESIGN:A cross-sectional study in which quota-controlled, nationally-representative samples of approximately 1000 adults from each country completed a face-to-face interview-assisted questionnaire.

    SETTING:The survey was conducted between October 1995 and February 1996 in the 15 member states of the European Union.

    SUBJECTS:14,331 subjects (aged 15 y upwards) completed the questionnaire. Data were weighted by population size for each country and by sex, age and regional distribution within each member state.

    RESULTS:71% of EU subjects agreed with the statement 'I do not need to make changes to the food I eat, as it is already healthy enough'. There was wide variation between the member states ranging from 47% in Finland to 87% in Italy indicating agreement. Overall there was little difference between the sexes except in Austria, Belgium, Germany, Greece and Ireland, but the proportions of subjects agreeing with the statement generally increased with advancing age and decreased with higher levels of education. The effects of demographics were not consistent across member states. A total of 49% of EU subjects agreed with the statement 'I usually do not think of the nutritional aspects of the food I eat'. Significantly more females than males disagreed with the statement in all countries except Portugal. In all member states there were widespread beliefs that people in general should decrease their consumption of savoury snacks and increase their consumption of fruit and vegetables.

    CONCLUSIONS:The results of this study demonstrate that dietary advice may not be perceived as personally relevant among EU subjects. In addition important target groups for the promotion of healthy eating have been identified for example, males or subjects with low levels of education. Because of the variation in attitudes a single pan-EU healthy eating programme is unlikely to be effective for all countries or for different demographic groups.

    背景与目标: 目标 : 检查来自欧盟 (EU) 每个成员国的具有国家代表性的样本中改变饮食习惯的感知需求。
    设计 : 一项横断面研究,其中来自每个国家的大约1000名成年人的配额控制的,具有全国代表性的样本完成了面对面访谈辅助问卷。
    设置 : 调查是在欧盟15个成员国的1995年10月和1996年2月之间进行的。
    受试者 :14,331名受试者 (15岁以上) 完成了问卷调查。数据按每个国家的人口规模以及每个成员国的性别、年龄和地区分布加权。结果: 71% 的欧盟受试者同意 “我不需要改变我吃的食物” 的说法,因为它已经足够健康了。成员国之间的差异很大,从芬兰的47% 到意大利的87%,表明同意。总体而言,除奥地利,比利时,德国,希腊和爱尔兰外,性别之间几乎没有差异,但同意该声明的受试者的比例通常随着年龄的增长而增加,而随着教育水平的提高而减少。各会员国人口统计的影响并不一致。共有49% 名欧盟受试者同意 “我通常不认为我所吃的食物的营养方面” 的说法。在除葡萄牙以外的所有国家,不同意这一说法的女性明显多于男性。在所有成员国中,人们普遍认为人们应该减少咸味小吃的消费,并增加水果和蔬菜的消费。
    结论 : 这项研究的结果表明,在欧盟受试者中,饮食建议可能不被认为与个人相关。此外,还确定了促进健康饮食的重要目标群体,例如男性或教育水平较低的受试者。由于态度的差异,单一的泛欧盟健康饮食计划不太可能对所有国家或不同的人口群体有效。
  • 【使用受控DNase I处理和实时PCR跟踪染色质状态。】 复制标题 收藏 收藏
    DOI:10.2478/s11658-007-0024-z 复制DOI
    作者列表:Martins RP,Platts AE,Krawetz SA
    BACKGROUND & AIMS: :A novel approach to DNase I-sensitivity analysis was applied to examining genes of the spermatogenic pathway, reflective of the substantial morphological and genomic changes that occur during this program of differentiation. A new real-time PCR-based strategy that considers the nuances of response to nuclease treatment was used to assess the nuclease susceptibility through differentiation. Data analysis was automated with the K-Lab PCR algorithm, facilitating the rapid analysis of multiple samples while eliminating the subjectivity usually associated with C(t) analyses. The utility of this assay and analytical paradigm as applied to nuclease-sensitivity mapping is presented.
    背景与目标: : DNase I敏感性分析的新方法被用于检查生精途径的基因,反映了在此分化程序中发生的实质性形态和基因组变化。一种新的基于实时PCR的策略,该策略考虑了对核酸酶处理的细微差别,用于通过分化评估核酸酶的敏感性。使用K-Lab PCR算法自动进行数据分析,从而促进了对多个样品的快速分析,同时消除了通常与C(t) 分析相关的主观性。介绍了该分析方法和分析范例应用于核酸酶敏感性映射的实用性。
  • 【地塞米松抑制促肾上腺皮质激素释放激素刺激试验和去莫加压素试验,以区分库欣综合征和假库欣状态。】 复制标题 收藏 收藏
    DOI:10.1111/j.1365-2265.2007.02926.x 复制DOI
    作者列表:Martin NM,Dhillo WS,Meeran K
    BACKGROUND & AIMS: -2
    背景与目标: -2
  • 【早产儿气管内吸痰过程中行为状态对脑氧合的影响。】 复制标题 收藏 收藏
    DOI:10.1055/s-2007-973682 复制DOI
    作者列表:Bernert G,von Siebenthal K,Seidl R,Vanhole C,Devlieger H,Casaer P
    BACKGROUND & AIMS: :Near infrared spectroscopy (NIRS) was used to investigate the effect of behavioural states on changes of oxygenated (O2Hb), deoxygenated haemoglobin (HHb) and total haemoglobin (tHb), during endotracheal suctioning. In an open prospective design, NIRS measurements have been done during 20 suctioning episodes in 13 preterm neonates. Heart rate, arterial oxygen saturation, and carbon dioxide tension were monitored continuously. Behavioural state (BS) observations were made and documented as well. The statistical analysis showed that in patients who were active, with crying periods during suctioning (behavioural states 4-5), changes of oxygenated (p < 0.005) and deoxygenated haemoglobin (p < 0.05), as well as of arterial oxygen saturation (p < 0.05) and heart rate (p < 0.05) were significantly greater than in patients who were quiet with predominant behavioural state 1, 2 and 3. These results underline the influence of behavioural states on the physiological answers to endotracheal suctioning. NIRS proved to be a valuable tool to evaluate possible harmful effects of different suctioning techniques.
    背景与目标: : 近红外光谱 (NIRS) 用于研究行为状态对气管内抽吸过程中含氧 (O2Hb),脱氧血红蛋白 (HHb) 和总血红蛋白 (tHb) 变化的影响。在开放的前瞻性设计中,已在13例早产新生儿的20次吸痰发作中进行了NIRS测量。连续监测心率,动脉血氧饱和度和二氧化碳张力。还进行了行为状态 (BS) 观察并记录在案。统计分析显示,在活动的患者中,在吸痰过程中有哭闹期 (行为状态4-5),氧合 (p < 0.005) 和脱氧血红蛋白 (p < 0.05) 的变化,动脉血氧饱和度 (p < 0.05) 和心率 (p < 0.05) 均显着高于以主要行为状态1、2和3安静的患者。这些结果强调了行为状态对气管内抽吸的生理答案的影响。事实证明,NIRS是评估不同抽吸技术可能产生的有害影响的宝贵工具。
  • 【体内NADH的氧化还原状态: 从动物到临床应用。】 复制标题 收藏 收藏
    DOI:10.1016/j.mito.2007.05.001 复制DOI
    作者列表:Mayevsky A,Chance B
    BACKGROUND & AIMS: :Mitochondrial dysfunction is part of many pathological states in patients, such as sepsis or stroke. Presently, the monitoring of mitochondrial function in patients is extremely rare, even though NADH redox state is routinely measured in experimental animals. In this article, we describe the scientific backgrounds and practical use of mitochondrial NADH fluorescence measurement that was applied to patients in the past few years. In addition to NADH, we optically measured the microcirculatory blood flow and volume, as well as HbO(2) oxygenation, from the same tissue area. The four detected parameters provide real time data on tissue viability, which is critical for patients monitoring.
    背景与目标: 线粒体功能障碍是患者许多病理状态的一部分,如败血症或中风。目前,即使在实验动物中常规测量NADH氧化还原状态,对患者线粒体功能的监测也极为罕见。在本文中,我们描述了过去几年应用于患者的线粒体NADH荧光测量的科学背景和实际用途。除NADH外,我们还从同一组织区域光学测量了微循环血流量和体积,以及HbO(2) 氧合。检测到的四个参数提供了有关组织活力的实时数据,这对于患者的监测至关重要。
  • 【美国睡眠实验室活动的定量评估。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Tachibana N,Ayas NT,White DP
    BACKGROUND & AIMS: STUDY OBJECTIVES:To determine the total number of active sleep laboratories in the United States and the number of polysomnograms conducted on a yearly basis in these laboratories. METHODS:All members of the AASM and all AASM accredited sleep laboratory directors received a questionnaire addressing their laboratory and its volume. In three states, multiple telephone calls to AASM members were used to correctly identify the absolute number of labs and their PSG volume in those states. Extrapolating from the number of labs studies identified per questionnaire relative to the correct number (per calls) in those states and, then applying this ratio to the entire US, the total number of labs and studies was determined. RESULTS:Our data suggests that there are, in the year 2001, 1,292 sleep laboratories conducting 1,165,135 polysomnograms per year. This comes to 427 PSG's/year per 100,000 population in the United States. CONCLUSIONS:These data suggest that there are a relatively large number of sleep laboratories in the US conducting a substantial number of PSG's. However, there was considerable variability in this volume between states that did not relate to known markers of healthcare utilization. These numbers have likely increased since 2001.
    背景与目标:
  • 【丙型肝炎感染初始检测的位置和原因-慢性肝炎队列研究,美国,2006-2010。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Centers for Disease Control and Prevention (CDC).
    BACKGROUND & AIMS: :Chronic hepatitis C virus (HCV) infection causes substantial morbidity and mortality in the United States. Testing and treatment of asymptomatic persons might avert progression to more advanced disease. In 1998, CDC published guidelines for HCV testing based on risk factors for infection; however, recent studies indicate that at least one half of all persons living with HCV infection in the United States are unaware of their infection status. To increase testing rates, in 2012 CDC recommended one-time testing of all persons born during 1945-1965. To better understand where and why persons with chronic HCV infection sought their initial testing, 2006-2010 data were analyzed from a survey conducted as part of the ongoing Chronic Hepatitis Cohort Study. Of 4,689 patients with HCV infection who responded to the survey, 60.4% reported that their initial HCV test occurred in a physician's office. CDC's risk-based indications (e.g., injection drug use and hemodialysis) were cited by 1,045 (22.3%) of the patients as reasons for testing, whereas clinical indications (e.g., abnormal liver function tests or liver-related symptoms such as jaundice) were cited by 2,121 (45.2%), suggesting that many HCV infections were identified only after the patient had become symptomatic. Promoting U. S. Preventive Services Task Force and CDC recommendations for testing and identifying strategies that help physicians implement HCV testing in their offices might help facilitate timely identification of HCV infection and reduce morbidity and mortality.
    背景与目标: : 在美国,慢性丙型肝炎病毒 (HCV) 感染会导致大量的发病率和死亡率。无症状者的检测和治疗可能会避免进展到更晚期的疾病。1998年,疾病预防控制中心发布了基于感染危险因素的HCV检测指南; 然而,最近的研究表明,在美国,至少有一半的HCV感染者不知道他们的感染状况。为了提高检测率,2012年疾病预防控制中心建议对1945-1965年期间出生的所有人进行一次性检测。为了更好地了解慢性HCV感染者在哪里以及为什么要进行初步测试,从正在进行的慢性肝炎队列研究的一部分进行的一项调查中分析了2006-2010的数据。在对调查做出回应的4,689例HCV感染患者中,60.4% 例报告说他们最初的HCV测试在医生办公室进行。1,045 (22.3%) 的患者引用CDC的基于风险的适应症 (例如,注射药物使用和血液透析) 作为测试的原因,而临床适应症 (例如,2,121 (45.2%) 引用了肝功能检查异常或肝脏相关症状 (例如黄疸),这表明仅在患者出现症状后才发现许多HCV感染。促进美国预防服务工作组和疾病预防控制中心的检测和识别策略的建议,帮助医生在其办公室实施HCV检测,可能有助于及时识别HCV感染,降低发病率和死亡率。
  • 【不同生理状态下分裂和非分裂四膜虫细胞的特征。】 复制标题 收藏 收藏
    DOI:10.1016/S0932-4739(11)80272-5 复制DOI
    作者列表:Hellung-Larsen P,Lyhne I,Andersen AP,Koppelhus U
    BACKGROUND & AIMS: :Eight defined physiological states of Tetrahymena pyriformis are described. For dividing cells the states comprise: 1. Exponentially growing cells, 2. Cells at late exponential growth phase, 3. Cells kept at a high cell concentration, 4. Cells shifted up or down by change of medium, temperature or degree of aeration. For non-dividing cells the states are: 5. Cells at stationary phase, 6. Cells during starvation, 7. Cells during shift-up after long-term starvation, 8. Cells at self-induced hypoxia. The different cellular states are described by one or more of the following characteristics: growth rate, volume, swimming speed, oxygen consumption and by the oxygen saturation and the pH in the medium. The results show that T. pyriformis grows equally well in proteose-peptone (PY) medium from 1 cell ml(-1) to 10(3) cells ml(-1) as from - e.g. - 10(2) to 10(5) cells ml(-1). The maximum cell concentration obtained depends on the medium and the availability of oxygen. At shift-down by decrease of temperature the cells grow slower and obtain a considerable oversize. Single cells tolerate starvation for 12 days. The cell volume (electronically determined) decreased from about 7000 μm(3) to about 200 μm(3). Long-term starved cells may be upshifted. Thereby growth without cell division can be studied until the cell volume approaches 2100 μm(3) which is the minimum volume of division competence. Under certain conditions cells may grow into self-induced hypoxia leading to growth arrest. These cells will attain an oversize. The swimming speed at 28°C of exponentially growing cells is 0.33 to 0.59 mm sec(-1) depending on the medium. At lower temperature the swimming speed is decreased. In PY-medium the values are: 28°C (0.57), 16°C (0.50), 9°C (0.37). During starvation the swimming speed decreases from about 0.6 to about 0.1 mm sec(-1) (after 6 days). The oxygen consumption is for state 1 cells: 3.9 μl O(2)/10(6) cells min(-1) (maximal value). The value of hypoxic cultures is 2.1, for cells kept at high concentration 0.4, and for starved cells (24 h) 0.2.
    背景与目标: : 描述了四膜虫的八种定义的生理状态。对于分裂细胞,状态包括: 1.指数生长的细胞,2。指数生长期晚期的细胞,3。细胞保持在较高的细胞浓度,4。细胞因介质、温度或曝气程度的变化而上下移动。对于非分裂细胞,状态为: 5。处于固定相的细胞,6。饥饿期间的细胞,7.长期饥饿后上移的细胞,8。自我诱导缺氧的细胞。不同的细胞状态由以下一个或多个特征描述: 生长速率,体积,游泳速度,耗氧量以及培养基中的氧饱和度和pH。结果表明,在从1细胞ml(-1) 到10(3) 细胞ml(-1) 的蛋白酶-蛋白胨 (PY) 培养基中,从-例如-10(2) 到10(5) 细胞ml(-1)。获得的最大细胞浓度取决于培养基和氧气的可用性。由于温度降低而向下移动时,细胞生长较慢,并获得相当大的尺寸。单细胞耐受饥饿12天。细胞体积 (电子测定) 从约7000微米 (3) 减少到约200微米 (3)。长期饥饿的细胞可能会向上移动。因此,可以研究没有细胞分裂的生长,直到细胞体积接近2100微米 (3),这是分裂能力的最小体积。在某些条件下,细胞可能会生长成自发性缺氧,从而导致生长停滞。这些细胞将变得超大。指数生长细胞在28 °C下的游动速度根据培养基0.33至0.59毫米秒 (-1)。在较低的温度下,游泳速度降低。在PY介质中,值为: 28 °C (0.57) 、16 °C (0.50) 、9 °C (0.37)。在饥饿期间,游泳速度从大约0.6秒 (-1) 降低到大约0.1毫米秒 (6天后)。耗氧量为状态1细胞: 3.9 μ l〇 (2)/10(6) 细胞min(-1) (最大值)。对于保持在高浓度0.4的细胞和对于饥饿的细胞 (24小时) 0.2,低氧培养物的价值是2.1的。

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