• 【不满意的巴氏涂片的临床病理相关性。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Ransdell JS,Davey DD,Zaleski S
    BACKGROUND & AIMS: BACKGROUND:The 1991 Bethesda System for cervical/vaginal cytology reporting defined adequacy criteria for the unsatisfactory designation. Most laboratories have implemented these criteria, but clinical implications have not been established.

    METHODS:Researchers at two university hospitals retrieved by computer search all unsatisfactory Papanicolaou (Pap) smears taken between January 1994 and July 1995. Of 71,872 total Pap smears, 208 (0.3%) were unsatisfactory (corresponding atypical rate of 9% and a dysplasia/carcinoma rate of 6.5%). Time interval to follow-up and clinicopathologic outcome were determined.

    RESULTS:Approximately 26% of unsatisfactory Pap smears were from patients with a history of epithelial abnormalities. The majority (129 of 208 specimens; 62%) of follow-up Pap smears or biopsies occurred within 6 months, 5.7% within 6-12 months, and 1.4% in 12-18 months. Approximately 31% had no follow-up. The first repeat Pap smear or histologic specimen in 144 patients with follow-up was negative in 107 (74%), unsatisfactory in 6 (4%), atypical squamous cells of undetermined significance in 15 (10%), squamous intraepithelial lesion (SIL) in 13 (9%), and malignant in 3 (2%). Nonmalignant conditions contributing to the unsatisfactory smears on histologic specimens (12%) included cervicitis, endometritis, endometrial hyperplasia, and polyps. Progressive abnormalities after the first repeat specimen were noted in 7 patients (5%). A total of 23 of 144 initial unsatisfactory specimens (16% )were found to be from patients diagnosed with SIL or malignancy when all follow-up specimens were analyzed.

    CONCLUSIONS:The majority of patients with unsatisfactory Pap smears had follow-up studies within 6 months. A significant number (16%) of those with follow-up had eventual diagnoses of SIL or neoplasia. Benign pathologic conditions also contributed to unsatisfactory smears. This patient subset was more likely to have a history of abnormalities, confirming the importance of peer/hierarchical review of unsatisfactory smears.

    背景与目标: 背景 : 1991的Bethesda宫颈/阴道细胞学报告系统定义了不令人满意的指定的充分性标准。大多数实验室已经实施了这些标准,但尚未确定临床意义。
    方法 : 两所大学医院的研究人员通过计算机搜索检索了1994年1月和1995年7月之间所有不满意的Papanicolaou (Pap) 涂片。在71,872的子宫颈抹片检查中,208 (0.3%) 不令人满意 (相应的非典型9% 率和不典型增生/癌率为6.5%)。确定了随访的时间间隔和临床病理结果。
    结果 : 大约26% 的不满意的子宫颈抹片检查来自有上皮异常病史的患者。大多数 (208标本129; 62%) 的随访子宫颈抹片检查或活检发生在6个月内,5.7% 发生在6-12个月内,1.4% 发生在12-18个月内。大约31% 没有随访。144例随访患者的首次重复巴氏涂片或组织学标本阴性107例 (74% 例),不满意6例 (4%),非典型鳞状上皮细胞未明确意义15例 (10% 例),鳞状上皮内病变 (SIL) 13例 (9%),恶性3例 (2% 例)。导致组织学标本涂片不令人满意的非恶性疾病 (12%) 包括宫颈炎,子宫内膜炎,子宫内膜增生和息肉。在7例患者 (5%) 中发现了第一个重复标本后的进行性异常。在分析所有随访标本时,发现144例初始不满意标本中的23例 (16% 例) 来自诊断为SIL或恶性肿瘤的患者。
    结论 : 大多数子宫颈抹片检查不满意的患者在6个月内进行了随访研究。大量 (16%) 随访的患者最终诊断为SIL或肿瘤。良性病理状况也导致涂片不令人满意。该患者子集更有可能有异常病史,这证实了对不满意的涂片进行同行/分级审查的重要性。
  • 【基于核移植的牛心肌细胞重编程研究隔离。】 复制标题 收藏 收藏
    DOI:10.1089/clo.2006.8.150 复制DOI
    作者列表:Schwarzer M,Carnwath JW,Lucas-Hahn A,Lemme E,Kues WA,Wachsmann B,Haverich A,Martin U,Niemann H
    BACKGROUND & AIMS: :The goal of this study was to establish and validate a protocol for preparing bovine cardiomyocytes from slaughterhouse material for nuclear transfer experiments. The cardiomyocyte was selected because it is a terminally differentiated cell and strongly expresses a unique subset of genes which can be monitored during the reprogramming period. A total of 39 trials were conducted, and an optimized protocol was developed yielding individual contractile cardiomyocytes from 3-5-month-old bovine fetuses The basic protocol involves stabilization of bovine heart tissue for transportation from the slaughterhouse to the laboratory by perfusion with Custodiol. This was followed by an enzymatic dissociation with collagenase in calcium-free medium and yielded individual contractile rod-shaped cardiomyocytes. Subsequent addition of Ca2+ caused the cardiomyocytes to round up which was an essential pre-condition for drawing them into glass transfer pipettes for delivery into the perivitelline space and for efficient electrofusion with cytoplasts derived from in vitro matured bovine oocytes. The use of cardiomyocytes maintained at 37 degrees C in nuclear transfer, resulted in a significantly reduced proportion of blastocysts compared to adult fibroblasts (14.0% versus 32.7%). Storage of cardiomyocytes at 4 degrees C prior to nuclear transfer was not compatible with blastocyst development. It is expected that this system will be valuable for investigating the reprogramming of gene expression which occurs after somatic cell nuclear transfer.
    背景与目标: : 这项研究的目的是建立和验证从屠宰场材料中制备牛心肌细胞以进行核移植实验的协议。选择心肌细胞是因为它是终末分化的细胞,并且强烈表达可以在重编程期间监测的独特基因子集。总共进行了39项试验,并开发了一种优化的方案,从3-5个月大的牛胎儿中产生了单个收缩心肌细胞。基本方案涉及稳定牛心脏组织,以便通过灌注从屠宰场运输到实验室。保管二醇。随后在无钙培养基中与胶原酶酶解离,并产生单个收缩的杆状心肌细胞。随后添加Ca2会导致心肌细胞四舍五入,这是将其吸入玻璃转移移液管以输送到卵黄周围空间以及与来自体外成熟牛卵母细胞的细胞质进行有效电融合的必要前提。与成人成纤维细胞相比,在核转移中使用维持在37 ℃ 的心肌细胞导致胚泡的比例显著降低 (14.0% 对32.7%)。在核转移之前在4摄氏度下储存心肌细胞与胚泡发育不相容。预计该系统对于研究体细胞核移植后发生的基因表达的重编程将很有价值。
  • 【经皮给药颗粒加速的性能研究。】 复制标题 收藏 收藏
    DOI:10.1007/s11517-006-0050-4 复制DOI
    作者列表:Liu Y
    BACKGROUND & AIMS: :We have proposed a transdermal biolistic method to accelerate a powder formulation of drugs to penetrate human skin for the treatment of a range of diseases. One of the key issues for designing and evaluating transdermal biolistic system is ensuing that the powder drugs are delivered into the skin with a controllable velocity range and spatial distribution. The aerodynamics of supersonic nozzles and performance of the delivery system were initially studied, mainly analytically and experimentally. In this paper, computational fluid dynamics is utilized to characterize two existing prototype devices, in order to further investigate the transient gas and particle dynamics in their supersonic nozzles. To validate the implemented numerical approach, calculated pressure histories, two-dimensional flow structures and particle velocity distributions are made and compared with the reported experimental measurements. The key features of gas dynamics, gas-particle interaction and performance of the prototype transdermal biolistics are discussed and interpreted.
    背景与目标: : 我们提出了一种经皮生物注射方法,以加速药物的粉末制剂渗透人体皮肤以治疗一系列疾病。设计和评估透皮生物成像系统的关键问题之一是,将粉末药物以可控的速度范围和空间分布输送到皮肤中。初步研究了超音速喷嘴的空气动力学和输送系统的性能,主要是通过分析和实验进行了研究。本文利用计算流体动力学来表征两个现有的原型设备,以便进一步研究其超音速喷嘴中的瞬态气体和颗粒动力学。为了验证所实施的数值方法,计算了压力历史,二维流动结构和颗粒速度分布,并与报告的实验测量值进行了比较。讨论并解释了气体动力学,气体-颗粒相互作用和原型透皮生物技术性能的关键特征。
  • 【罗非考昔是细胞色素P450 1A2的有效抑制剂: 在健康受试者中使用替扎尼定和咖啡因进行的研究。】 复制标题 收藏 收藏
    DOI:10.1111/j.1365-2125.2006.02653.x 复制DOI
    作者列表:Backman JT,Karjalainen MJ,Neuvonen M,Laitila J,Neuvonen PJ
    BACKGROUND & AIMS: AIMS:Case reports suggest an interaction between rofecoxib and the CYP1A2 substrate tizanidine. Our objectives were to explore the extent and mechanism of this possible interaction and to determine the CYP1A2 inhibitory potency of rofecoxib. METHODS:In a randomized, double-blind, two-phase cross-over study, nine healthy subjects took 25 mg rofecoxib or placebo daily for 4 days and, on day 4, each ingested 4 mg tizanidine. Plasma concentrations and the urinary excretion of tizanidine, its metabolites (M) and rofecoxib, and pharmacodynamic variables were measured up to 24 h. On day 3, a caffeine test was performed to estimate CYP1A2 activity. RESULTS:Rofecoxib increased the area under the plasma concentration-time curve (AUC(0-infinity)) of tizanidine by 13.6-fold [95% confidence interval (CI) 8.0, 15.6; P < 0.001), peak plasma concentration (C(max)) by 6.1-fold (4.8, 7.3; P < 0.001) and elimination half-life (t(1/2)) from 1.6 to 3.0 h (P < 0.001). Consequently, rofecoxib markedly increased the blood pressure-lowering and sedative effects of tizanidine (P < 0.05). Rofecoxib increased several fold the tizanidine/M-3 and tizanidine/M-4 ratios in plasma and urine and the tizanidine/M-5, tizanidine/M-9 and tizanidine/M-10 ratios in urine (P < 0.05). In addition, it increased the plasma caffeine/paraxanthine ratio by 2.4-fold (95% CI 1.4, 3.4; P = 0.008) and this ratio correlated with the tizanidine/metabolite ratios. Finally, the AUC(0-25) of rofecoxib correlated with the placebo phase caffeine/paraxanthine ratio (r = 0.80, P = 0.01). CONCLUSIONS:Rofecoxib is a potent inhibitor of CYP1A2 and it greatly increases the plasma concentrations and adverse effects of tizanidine. The findings suggest that rofecoxib itself is also metabolized by CYP1A2, raising concerns about interactions between rofecoxib and other CYP1A2 substrate and inhibitor drugs.
    背景与目标:
  • 【通过临床分离株新基因的鉴定和分布研究,揭示了铜绿假单胞菌广泛的基因组可塑性。】 复制标题 收藏 收藏
    DOI:10.1128/IAI.00546-06 复制DOI
    作者列表:Shen K,Sayeed S,Antalis P,Gladitz J,Ahmed A,Dice B,Janto B,Dopico R,Keefe R,Hayes J,Johnson S,Yu S,Ehrlich N,Jocz J,Kropp L,Wong R,Wadowsky RM,Slifkin M,Preston RA,Erdos G,Post JC,Ehrlich GD,Hu FZ
    BACKGROUND & AIMS: :The distributed genome hypothesis (DGH) states that each strain within a bacterial species receives a unique distribution of genes from a population-based supragenome that is many times larger than the genome of any given strain. The observations that natural infecting populations are often polyclonal and that most chronic bacterial pathogens have highly developed mechanisms for horizontal gene transfer suggested the DGH and provided the means and the mechanisms to explain how chronic infections persist in the face of a mammalian host's adaptive defense mechanisms. Having previously established the validity of the DGH for obligate pathogens, we wished to evaluate its applicability to an opportunistic bacterial pathogen. This was accomplished by construction and analysis of a highly redundant pooled genomic library containing approximately 216,000 functional clones that was constructed from 12 low-passage clinical isolates of Pseudomonas aeruginosa, 6 otorrheic isolates and 6 from other body sites. Sequence analysis of 3,214 randomly picked clones (mean insert size, approximately 1.4 kb) from this library demonstrated that 348 (10.8%) of the clones were unique with respect to all genomic sequences of the P. aeruginosa prototype strain, PAO1. Hypothetical translations of the open reading frames within these unique sequences demonstrated protein homologies to a number of bacterial virulence factors and other proteins not previously identified in P. aeruginosa. PCR and reverse transcription-PCR-based assays were performed to analyze the distribution and expression patterns of a 70-open reading frame subset of these sequences among 11 of the clinical strains. These sequences were unevenly distributed among the clinical isolates, with nearly half (34/70) of the novel sequences being present in only one or two of the individual strains. Expression profiling revealed that a vast majority of these sequences are expressed, strongly suggesting they encode functional proteins.
    背景与目标: : 分布式基因组假说 (DGH) 指出,细菌物种中的每个菌株都从基于群体的上基因组接收到独特的基因分布,该基因分布比任何给定菌株的基因组大很多倍。观察到自然感染种群通常是多克隆的,并且大多数慢性细菌病原体具有高度发达的水平基因转移机制,这表明DGH并提供了手段和机制来解释慢性感染如何在哺乳动物宿主的适应性防御机制中持续存在。先前已经确定了DGH对专性病原体的有效性,我们希望评估其对机会性细菌病原体的适用性。这是通过构建和分析包含约216,000个功能克隆的高度冗余的合并基因组文库来实现的,所述基因组文库是从铜绿假单胞菌的12个低传代临床分离株、6个耳鼻喉科分离株和6个来自其他身体位点构建的。对从该文库中随机挑选的3,214个克隆 (平均插入大小,约1.4 kb) 的序列分析表明,对于铜绿假单胞菌原型菌株pao1的所有基因组序列,348 (10.8%) 的克隆是独特的。这些独特序列中开放阅读框的假设翻译证明了蛋白质与许多细菌毒力因子和其他以前在铜绿假单胞菌中未鉴定的蛋白质的同源性。进行了PCR和基于逆转录PCR的检测,以分析11种临床菌株中这些序列的70个开放阅读框子集的分布和表达模式。这些序列在临床分离株中分布不均匀,近一半 (34/70) 新序列仅存在于单个菌株中的一个或两个中。表达谱分析显示,这些序列中的绝大多数都被表达,这强烈表明它们编码功能蛋白。
  • 【使用口译员的跨文化访谈研究: 系统的文献综述。】 复制标题 收藏 收藏
    DOI:10.1111/j.1365-2648.2006.03963.x 复制DOI
    作者列表:Wallin AM,Ahlström G
    BACKGROUND & AIMS: AIM:This paper reviews how the interpreter's role is described in empirically based, qualitative cross-cultural interview studies and how trustworthiness is determined. BACKGROUND:Increased immigration during the past decades has created a multiethnic society in many countries. This development poses a challenge to healthcare staff, in that they need to understand how people from different cultures experience health and illness. One way to assess immigrants' experiences is through cross-cultural interview studies, involving an interpreter. Thorough knowledge of the interpreter's role is needed in order to increase the trustworthiness of this kind of nursing research. METHOD:Literature searches were conducted from October to November 2004 using PubMed, CINAHL, Psycinfo, Sociological abstract, Your Journals@ovid, and Eric databases. Qualitative interview studies written in English and performed with an interpreter were included. The Matrix Method was used to review the literature. FINDINGS:In almost all of the 13 relevant papers found, the role of the interpreter(s) in the research process was only sparsely described. In addition, all studies except one employed different techniques to established trustworthiness. The most common techniques were prolonged engagement, member check or triangulation, the latter performed either on the data, investigators or methods. CONCLUSION:Methodological issues with respect to interpreters have received only limited attention in cross-cultural interview studies. Researchers in the field of nursing need to consider (1) the interpreter's role/involvement in the research process; (2) the interpreter's competence and the style of interpreting; (3) the interpreter's impact on the findings. This information is a prerequisite when trying to determine the trustworthiness of a cross-cultural study.
    背景与目标:
  • 【P53基因的等位基因丢失与膀胱癌的肿瘤分级,分期和恶性进展的相关性。】 复制标题 收藏 收藏
    DOI:10.1111/j.1442-2042.1997.tb00144.x 复制DOI
    作者列表:Tsutsumi M,Sugano K,Yamaguchi K,Kakizoe T,Akaza H
    BACKGROUND & AIMS: BACKGROUND:We examined loss of heterozygosity (LOH) of the P53 gene in bladder cancer, and investigated the role of the P53 gene on malignant progression of papillary tumors. In addition, the clonality of recurrent bladder cancer was examined. METHODS:LOH of the P53 gene was analyzed in 67 bladder cancers from 47 patients. DNA was extracted from formalin-fixed, paraffin-embedded tissues, amplified by the polymerase chain reaction (PCR) at 3 polymorphic loci in the P53 gene, and analyzed with nonradioisotopic single-strand conformation polymorphism (Non-RI SSCP) analysis. RESULTS:Out of 40 informative samples, LOH was detected in 13 samples, containing 4 of 7 in grade 3 (57%), 9 of 23 in grade 2 (39%), and none of 10 in grade 1 (10%). Statistical significance was observed between the LOH in grades 1 and 2, and in grades 1 and 3. An analysis of 5 cases showing malignant progression revealed that 3 (60%) showed an LOH in the primary tumor, and 2 showed LOH in recurrent tumors, in contrast to LOH found in 3 cases of 19 (16%) not showing malignant progression. Four cases with metachronous recurrence exhibited LOH; 2 at recurrent tumors, 1 only at the initial tumor, and 1 at both tumors. CONCLUSIONS:The alterations of the P53 gene were considered to correlate with tumor grade, and contribute to the malignant progression of bladder cancer. LOH in the P53 gene may serve as a clinical indicator for prognosis in superficial bladder cancer.
    背景与目标:
  • 【CROPPER: 用于跨平台和跨物种汇编研究的metagene creator资源。】 复制标题 收藏 收藏
    DOI:10.1186/1471-2105-7-418 复制DOI
    作者列表:Paananen J,Storvik M,Wong G
    BACKGROUND & AIMS: BACKGROUND:Current genomic research methods provide researchers with enormous amounts of data. Combining data from different high-throughput research technologies commonly available in biological databases can lead to novel findings and increase research efficiency. However, combining data from different heterogeneous sources is often a very arduous task. These sources can be different microarray technology platforms, genomic databases, or experiments performed on various species. Our aim was to develop a software program that could facilitate the combining of data from heterogeneous sources, and thus allow researchers to perform genomic cross-platform/cross-species studies and to use existing experimental data for compendium studies. RESULTS:We have developed a web-based software resource, called CROPPER that uses the latest genomic information concerning different data identifiers and orthologous genes from the Ensembl database. CROPPER can be used to combine genomic data from different heterogeneous sources, allowing researchers to perform cross-platform/cross-species compendium studies without the need for complex computational tools or the requirement of setting up one's own in-house database. We also present an example of a simple cross-platform/cross-species compendium study based on publicly available Parkinson's disease data derived from different sources. CONCLUSION:CROPPER is a user-friendly and freely available web-based software resource that can be successfully used for cross-species/cross-platform compendium studies.
    背景与目标:
  • 【11号真空辅助立体定向活检的小叶瘤形成: 与手术切除活检和乳房x线摄影随访的相关性。】 复制标题 收藏 收藏
    DOI:10.2214/AJR.05.0710 复制DOI
    作者列表:Mahoney MC,Robinson-Smith TM,Shaughnessy EA
    BACKGROUND & AIMS: OBJECTIVE:The objective of our study was to evaluate the outcome of lobular neoplasia diagnosed at 11-gauge stereotactic vacuum-assisted biopsy (SVAB). MATERIALS AND METHODS:Retrospective review of 1,819 lesions sampled with 11-gauge SVAB yielded 27 patients with lobular neoplasia as the most severe pathologic entity diagnosed. Patients with lobular neoplasia associated with atypical ductal hyperplasia (ADH), ductal carcinoma in situ (DCIS), or infiltrating carcinoma were excluded. Twenty patients underwent surgical excisional biopsy, and seven patients were followed mammographically for a mean of 52 months (range, 14-67 months). Mammographic lesion type, number of specimens obtained per lesion, and specific histologic features related to lobular carcinoma in situ (LCIS) were assessed. Results were compared with histologic findings at surgery or mammographic follow-up. RESULTS:Nineteen lesions presented mammographically as microcalcifications, four as masses, three as masses with associated microcalcifications, and one as architectural distortion. A mean of 13 specimens were obtained per lesion. Carcinoma was found at surgical excision in 19% of the lesions (5/27). Lesions were upgraded to DCIS (n = 2), invasive lobular carcinoma (n = 2), and mixed invasive ductal and lobular carcinoma (n = 1). In addition to the diagnosis of lobular neoplasia at SVAB, one patient presented with synchronous infiltrating ductal carcinoma in the contralateral breast, and two patients developed metachronous infiltrating ductal carcinoma in a different quadrant of the ipsilateral breast. Twelve of the 27 lesions included LCIS. These lesions were evaluated pathologically to distinguish the classic (10/12) from the pleomorphic (2/12) form of this entity. Ten of the 12 LCIS cases underwent surgical excisional biopsy with four of the five upgrades occurring in these patients. Only one of these patients was shown to have the pleomorphic type of LCIS. Lesions in seven patients who underwent mammographic follow-up remained stable. CONCLUSION:The known association of lobular neoplasia with high-risk and malignant lesions at surgical biopsy requires careful consideration when lobular neoplasia is diagnosed as the most severe histologic entity at SVAB. The diagnosis of lobular neoplasia at 11-gauge SVAB is not reliable in view of the 19% upgrade rate at the time of surgical excisional biopsy in our study. No predictive mammographic features allowed distinction between the patients with lesions that were upgraded at the time of surgery from those whose lesions were not upgraded.
    背景与目标:
  • 【残基Leu 93和Asp 96在细菌视紫红质光周期中独立起作用: 对leu 93->Ala,Asp 96->Asn双突变体的研究。】 复制标题 收藏 收藏
    DOI:10.1016/S0006-3495(96)79803-X 复制DOI
    作者列表:Delaney JK,Subramaniam S
    BACKGROUND & AIMS: Previous mutagenesis studies with bacteriorhodopsin have shown that reprotonation of the Schiff's base is the rate-limiting step in the photocycle of the D96N mutant, whereas retinal re-isomerization and return of the protein to the initial state constitute the rate-limiting events in the photocycle of the L93A mutant. Thus, in the D96N mutant, decay of the M intermediate is slowed down by more than 100-fold at pH 7. In the L93A mutant, decay of the O intermediate is slowed down by 250-fold. We report here that in the L93A, D96N double mutant, decay of the M intermediate, as well as the formation and decay of the O intermediate, are slowed down dramatically. The photocycle is completed by the decay of a long-lived O intermediate, as in the L93A mutant. The decay of the M and O intermediates in the double mutant parallels the behavior seen in the single mutants over a wide temperature and pH range, arguing that the observed independence is an intrinsic property of the mutant. The slow decay of the M and O intermediates can be selectively and independently reversed under conditions identical to those used for the corresponding intermediates in the D96N and L93A single mutants. Because the effects of the two individual mutations are preserved in the double mutant and can be independently reversed, we conclude that residues Asp 96 and Leu 93 act independently and at different stages of the bacteriorhodopsin photocycle. These results also show that formation of the O intermediate only requires protonation of the Schiff's base and is independent of the protonation of Asp 96 from the aqueous medium.

    背景与目标: 先前对细菌视紫红质的诱变研究表明,席夫碱的再质子化是D96N突变体光循环中的限速步骤,而视网膜再异构化和蛋白质返回到初始状态则构成了光循环中的限速事件。L93A突变体。因此,在D96N突变体中,M中间体的衰变在ph7下减慢了100倍以上。在L93A突变体中,O中间体的衰变减慢250倍。我们在这里报告说,在L93A,D96N双突变体中,M中间体的衰变以及O中间体的形成和衰变显着减慢。像L93A突变体一样,通过长寿命O中间体的衰变来完成光循环。双突变体中M和O中间体的衰变与在宽温度和pH范围内单个突变体中看到的行为相似,认为观察到的独立性是突变体的内在特性。M和O中间体的缓慢衰变可以在与D96N和L93A单个突变体中相应中间体所使用的条件相同的条件下选择性地和独立地逆转。由于两个个体突变的作用保留在双突变体中并且可以独立逆转,因此我们得出结论,残基Asp 96和Leu 93独立且在细菌视紫红质光循环的不同阶段起作用。这些结果还表明,O中间体的形成仅需要席夫碱的质子化,并且与水性介质中Asp 96的质子化无关。
  • 【神经放射学亚专业专家对脑ct成像研究的重新解释的质量结果。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Jordan MJ,Lightfoote JB,Jordan JE
    BACKGROUND & AIMS: PURPOSE:To determine the clinical importance and relative value of reinterpreting brain CT imaging studies by subspecialty experts regarding changes in clinical management. METHODS:Computerized records were queried at two institutions during the years 2002-2003 for both primary interpretation by board-certified nonneuroradiologists and secondary interpretation by three neuroradiologists. A total of 1,081 cases were reviewed. Each case was initially interpreted as an emergent or urgent study. The reinterpreted studies were scored as concordant or discordant by the subspecialty experts. The discordant studies were then categorized as a "major discordance" if there was a change in clinical management, or as a "minor discordance" if there was no impact or change in clinical management. RESULTS:Of the 1,081 studies reviewed, 14 studies were identified as discordant (1.3%). Of those discordant studies, four were categorized as major discrepancies necessitating a change in clinical management (0.4 %). Ten were categorized as minor discrepancies (0.9%). There were no permanent adverse outcomes with respect to morbidity and mortality as a result of any discrepancy. CONCLUSION:The vast majority of interpreted head CT cases read by board-certified general radiologists do not result in discordant interpretations as verified by subspecialty experts. Discordant interpretations did not result in changes in clinical management in most cases. Double reading of head CTs by subspecialty experts appears to be an inefficient method of substantially improving imaging health quality outcomes.
    背景与目标:
  • 【在急诊科新发癫痫发作患者中进行实验室研究的实用性。】 复制标题 收藏 收藏
    DOI:10.1016/s0196-0644(05)82337-6 复制DOI
    作者列表:Turnbull TL,Vanden Hoek TL,Howes DS,Eisner RF
    BACKGROUND & AIMS: :Extensive laboratory testing is often performed in the emergency department evaluation of the new-onset seizure patient. To determine the utility of such testing, a prospective study of patients with a new-onset seizure presenting to the ED of an inner-city, university-affiliated teaching hospital was done. One hundred thirty-six patients were entered into the study between October 1984 and January 1988. All patients had uniform data collection performed. Pertinent historical information and physical examination findings were recorded on a standardized form before laboratory abnormality was a sole or contributory cause of the seizure disorder. These included four patients with hypoglycemia, four with hyperglycemia, two with hypocalcemia, and one with hypomagnesemia. Only two cases (hypoglycemia) were not suspected on the basis of findings on the history or physical examination. In ED patients, the incidence of a new-onset seizure due to a correctable metabolic disturbance is low. We conclude that, with the exception of the serum glucose, the extensive ED laboratory workup often done for the evaluation of a new-onset seizure is unnecessary. Further test ordering should be directed by the medical history and physical examination.
    背景与目标: : 在急诊科对新发癫痫患者的评估中,经常进行广泛的实验室测试。为了确定这种测试的实用性,对向市中心大学附属教学医院的ED呈递的新发癫痫发作患者进行了前瞻性研究。在1984年10月和1988年1月之间,有136名患者进入了研究。所有患者均进行了统一的数据收集。在实验室异常是癫痫发作的唯一或促成原因之前,将相关的历史信息和体格检查结果记录在标准化表格上。其中包括4名低血糖患者,4名高血糖患者,2名低钙血症患者和1名低镁血症患者。根据病史或体格检查发现,仅怀疑有2例 (低血糖)。在ED患者中,由于可纠正的代谢紊乱而引起的新发癫痫发作的发生率较低。我们得出的结论是,除血清葡萄糖外,通常不需要进行广泛的ED实验室检查以评估新发癫痫发作。进一步的检查顺序应由病史和体格检查指示。
  • 【在假定的眼结核患者中,通过正电子发射断层扫描/计算机断层扫描 (PET/CT) 研究全身摄取18-fdg的模式。】 复制标题 收藏 收藏
    DOI:10.3109/09273948.2012.697596 复制DOI
    作者列表:Mehta S
    BACKGROUND & AIMS: AIM:To report the patterns and sites of 18-FDG uptake in patients of presumed ocular tuberculosis. MATERIALS AND METHODS:The clinical and investigational findings of 11 patients were reviewed retrospectively. These included 6 males and 5 females with a mean age of 46.2 years. 21 eyes were included in the data analysis. Clinical presentations include 15 eyes with anterior uveitis, 2 eyes with retinal vasculitis, 2 eyes with panuveitis and 2 eyes with multifocal choroidopathy. RESULTS:Two distinct patterns of systemic uptake emerged. Pattern 1: No detectable systemic uptake (4 patients). Pattern 2: Detectable systemic uptake. a. Chest disease only (2 patients). b. Disseminated pattern, uptake seen at multiple sites (4 patients). c. Extrapulmonary only (1 patient). CONCLUSIONS:Ocular tuberculosis may often be part of a wider disseminated disease.
    背景与目标:
  • 【甲状腺球蛋白特异性抑制T细胞功能在自身免疫性甲状腺疾病中的研究。】 复制标题 收藏 收藏
    DOI:10.1210/jcem-61-2-306 复制DOI
    作者列表:Mori H,Hamada N,DeGroot LJ
    BACKGROUND & AIMS: :T cell regulation of the generation of thyroglobulin plaque-forming cells (Tg PFC) and protein A plaque-forming cells (Prot A PFC) was investigated using lymphocytes from patients with autoimmune thyroid disease. T and B cell mixed cultures (T-B MC) were carried out without mitogenic or antigenic stimulation to identify physiological T cell effects in the system. Tg PFC were found in 8 (44%) of 18 patients who had high titers of thyroglobulin antibody in their sera. Tg-specific and nonspecific immunoregulation by T cells from patients and normal subjects was studied using B cells from these eight patients in the T-B MC system. Remarkably lower values of Tg PFC induction compared to Prot A PFC induction were found after T cell addition. Normal T cells inhibited Tg PFC induction, but patient T cells did not, while the same extent of helper effects were found on Prot A PFC induction by the addition of patient and normal T cells. Irradiation (1500 rads) of T cells from patients and normal subjects significantly enhanced both TgPFC and Prot A PFC induction. Thus, Tg-specific suppressor T cells are present in all normal subjects as part of the radiosensitive suppressor T cell subset. The increase in Tg-PFC caused by irradiation-induced inhibition of Tg-specific suppressor T cell function was significantly greater in normal subjects than in patients. Histamine type 2 receptor-bearing T cells inhibited Prot A PFC induction, but not Tg PFC induction, in the autologous T-B MC system. No Tg PFC were induced from normal B cells in any combination with untreated T cells, irradiated T cells, or histamine type 2 receptor-negative T cells from patients or normal subjects. These data indicate that in vitro Tg-specific T cell regulation can be studied in the T-B MC system by using B cells from patients with autoimmune thyroid disease with high Tg antibody titers in their sera. Tg-specific suppressor T cells appear to be present in all individuals and to be involved in the regulation of Tg antibody production. The lower activity of Tg-specific suppressor T cells in patients compared to that in normal subjects may be related to Tg antibody production in vivo. This abnormality, however, is heterogeneous and is not a complete but, rather, is a relative defect of Tg-specific suppressor T cells.
    背景与目标: : 使用自身免疫性甲状腺疾病患者的淋巴细胞研究了甲状腺球蛋白斑块形成细胞 (Tg PFC) 和蛋白A斑块形成细胞 (Prot A PFC) 生成的T细胞调节。在没有促有丝分裂或抗原刺激的情况下进行T细胞和b细胞混合培养 (t-b MC),以鉴定系统中的生理T细胞作用。在18例血清中甲状腺球蛋白抗体滴度较高的患者中,有8例 (44% 例) 发现了Tg PFC。在t-b MC系统中,使用这八名患者的b细胞研究了患者和正常受试者的T细胞对Tg的特异性和非特异性免疫调节。添加T细胞后,与Prot A PFC诱导相比,Tg PFC诱导值明显降低。正常T细胞抑制Tg PFC诱导,但患者T细胞不抑制,而通过添加患者和正常T细胞对Prot A PFC诱导发现了相同程度的辅助作用。来自患者和正常受试者的T细胞的照射 (1500 rads) 显着增强了TgPFC和Prot A PFC的诱导。因此,Tg特异性抑制T细胞作为放射敏感性抑制T细胞亚群的一部分存在于所有正常受试者中。在正常受试者中,由辐射诱导的Tg特异性抑制T细胞功能抑制引起的tg-pfc的增加明显大于患者。在自体t-b MC系统中,带有组胺2型受体的T细胞抑制Prot A PFC诱导,但不抑制Tg PFC诱导。正常b细胞与未经治疗的T细胞,辐照的T细胞或来自患者或正常受试者的组胺2型受体阴性T细胞的任何组合均未诱导Tg PFC。这些数据表明,可以使用来自血清中Tg抗体滴度较高的自身免疫性甲状腺疾病患者的b细胞,在t-b MC系统中研究体外Tg特异性T细胞调控。Tg特异性抑制T细胞似乎存在于所有个体中,并参与Tg抗体产生的调节。与正常受试者相比,患者中Tg特异性抑制T细胞的活性较低可能与体内Tg抗体的产生有关。然而,这种异常是异质的,不是完整的,而是Tg特异性抑制T细胞的相对缺陷。
  • 【模拟复杂的数据结构,以规划研究,重点是生物标志物比较。】 复制标题 收藏 收藏
    DOI:10.1186/s12874-017-0364-y 复制DOI
    作者列表:Schulz A,Zöller D,Nickels S,Beutel ME,Blettner M,Wild PS,Binder H
    BACKGROUND & AIMS: BACKGROUND:There are a growing number of observational studies that do not only focus on single biomarkers for predicting an outcome event, but address questions in a multivariable setting. For example, when quantifying the added value of new biomarkers in addition to established risk factors, the aim might be to rank several new markers with respect to their prediction performance. This makes it important to consider the marker correlation structure for planning such a study. Because of the complexity, a simulation approach may be required to adequately assess sample size or other aspects, such as the choice of a performance measure. METHODS:In a simulation study based on real data, we investigated how to generate covariates with realistic distributions and what generating model should be used for the outcome, aiming to determine the least amount of information and complexity needed to obtain realistic results. As a basis for the simulation a large epidemiological cohort study, the Gutenberg Health Study was used. The added value of markers was quantified and ranked in subsampling data sets of this population data, and simulation approaches were judged by the quality of the ranking. One of the evaluated approaches, the random forest, requires original data at the individual level. Therefore, also the effect of the size of a pilot study for random forest based simulation was investigated. RESULTS:We found that simple logistic regression models failed to adequately generate realistic data, even with extensions such as interaction terms or non-linear effects. The random forest approach was seen to be more appropriate for simulation of complex data structures. Pilot studies starting at about 250 observations were seen to provide a reasonable level of information for this approach. CONCLUSIONS:We advise to avoid oversimplified regression models for simulation, in particular when focusing on multivariable research questions. More generally, a simulation should be based on real data for adequately reflecting complex observational data structures, such as found in epidemiological cohort studies.
    背景与目标:

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