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The patellar ligament (PL) is an epiphyseal ligament and is part of the extensor complex of the knee. The ligament has gained attention due to its clinical relevance to autograft and tendinopathy. A variety of anatomical variations of the PL such as aplasia, numerical variations, and vascularity are being reported recently by clinicians and anatomists. The aim of this literature was to review the available literature to provide a consensus regarding anatomic variations of the PL, neurovasculature surrounding the PL, histology of the PL, and various aspects of PL measurements with relevance to the surgical considerations and sex and age-related differences. A narrative review of the patellar ligament was performed by conducting a detailed literature search and review of relevant articles. A total of 90 articles on the patellar ligament were included and were categorized into studies based on anatomical variations, neurovasculature, morphometrics, microanatomy, sex and age-related difference, and ACL reconstruction. The anatomical variations and morphometrics of the PL were found to correlate with the frequency of strain injuries, tendinopathy, and efficacy of the PL autograft in anterior cruciate ligament reconstruction. The sex differences in PL measurements and the effect of estrogen on collagen synthesis explained a higher incidence of patellar tendinopathy in women. An awareness of its variations enables careful selection of surgical incisions, thereby avoiding complications related to nerve injury. Accurate knowledge of the PL microanatomy assists in understanding the mechanism of ligament degeneration, rupture, autograft harvesting, and ligamentization results.  相似文献   
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Background: It is widely known that a proportion of university students use drugs. However, much less is known about how they source and supply their drugs. Objectives: In this article, we investigate student drug trading activity, including how they obtained their drugs, whether they sold drugs, and the extent to which their drug trading might be described as a form of “social supply”. Methods: A survey was conducted of all students across seven of the nine universities of Wales. In total, 7855 students submitted a questionnaire and 1877 of these reported drug use in the current academic year. All students who reported using one or more illegal drugs in the current academic year were asked how they obtained their drugs, how they funded their drug use, whether they had sold, traded or given away illegal drugs, along with their motives for drug trading. Results: The results showed that about half of users obtained drugs solely from friends and associates and one-fifth obtained them solely from external dealers. One-quarter used friends and associates as well as external markets. In many cases, supplying drugs amounted to sharing them or giving them away. However, over one-third of students said that they had sold drugs. Conclusions: Overall, the methods of sourcing and supplying drug among university students shares features of both “social supply” and “traditional” drug markets. We conclude that the student drug market investigated is best described as a “hybrid” combination of both.  相似文献   
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BACKGROUND: Computer-assisted image analysis has been proposed for human hair growth studies. METHODS: The performances of Trichoscan, a commercially available automated system combining epiluminiscence microscopy with digital image analysis, developed for office-based hair growth measurements, have been evaluated comparatively on the same skin sites using standardized photographic equipment and calibrated processing for contrast-enhanced phototrichogram (CE-PTG) analysis. This reference method has been validated with scalp biopsies and histological examination of serial sectioning. RESULTS: Besides edge effects, hair fibres escaped the Trichoscan analysis for various reasons including, but not limited to, thickness, pigmentation, closeness and crossing. CONCLUSION: Most of these problems have been identified in the late 1980s and remain largely unsolved by the processing software that was evaluated in 2004. Therefore claims promoting the Trichoscan method for accurate hair measurements in clinical trials on scalp and body hair are not supported by the present investigation. The speed at which the analysis is performed is outweighed by the errors in signal detection. Therefore we suggest that improvements must be clearly documented before Trichoscan is established for quantified diagnostic purposes and detailed hair cycle monitoring during hair trials.  相似文献   
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双波长紫外分光光度法测定贝母中腺苷和胸苷的含量   总被引:4,自引:0,他引:4  
将4种贝母的甲醇提取物经薄层色谱法粗分离后,直接用双波长紫外分光光度法测定其含量。结果表明,该方法线性关系好,腺苷和胸苷标准曲线的相关系数均为0.9999,同时也发现平贝、炉贝和伊贝中腺苷都占核苷总量60%以上,而浙贝中仅占约40%,提示贝母生药的抗凝血活性可能与贝母中核苷类化合物的种类和含量的差别有关。  相似文献   
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In this paper, the authors describe some of the complexities of collecting and presenting data on race and ethnicity based on the experiences of the Bureau of the Census. Different methods of data collection, different content and format of questions, and different definitions make it difficult to collect consistent race and ethnic data across data systems. The Bureau of the Census experiences have shown that changing ethnic self-identity and concepts, intent of the question, consistency of reporting, and the classification of persons of mixed racial parentage affect the quality of the data. These are some of the issues that must be addressed as statistical agencies and researchers seek to provide comparable race and ethnic data.  相似文献   
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The long-held belief that degeneration of the cholinergic basal forebrain was central to Alzheimer's disease (AD) pathogenesis and occurred early in the disease process has been questioned recently. In this regard, changes in some cholinergic basal forebrain (CBF) markers (e.g. the high affinity trkA receptor) but not others (e.g., cortical choline acetyltransferase [ChAT] activity, the number of ChAT and vesicular acetylcholine transporter-immunoreactive neurons) suggest specific phenotypic changes, but not frank neuronal degeneration, early in the disease process. The present study examined the expression of the low affinity p75 neurotrophin receptor (p75(NTR)), an excellent marker of CBF neurons, in postmortem tissue derived from clinically well-characterized individuals who have been classified as having no cognitive impairment (NCI), mild cognitive impairment (MCI), and mild AD. Relative to NCI individuals, a significant and similar reduction in the number of nucleus basalis p75(NTR)-immunoreactive neurons was seen in individuals with MCI (38%) and mild AD (43%). The number of p75(NTR)-immunoreactive nucleus basalis neurons was significantly correlated with performance on the Mini-Mental State Exam, a Global Cognitive Test score, as well as some individual tests of working memory and attention. These data, together with previous reports, support the concept that phenotypic changes, but not frank neuronal degeneration, occur early in cognitive decline. Although there was no difference in p75(NTR) CBF cell reduction between MCI and AD, it remains to be determined whether these findings lend support to the hypothesis that MCI is a prodromal stage of AD.  相似文献   
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This article reviews the anatomical and functional evidence for ascending pathways from specific brain regions to the PVN and SON which could influence AVP release. The majority of evidence favours the main projection being from a region in the caudal VLM which may coincide with the noradrenergic neurons of the A1 cell group. However, the transmitter(s) involved have yet to be identified, and whether the pathway is excitatory and/or inhibitory remains to be fully resolved.Anatomical and functional evidence is reviewed for descending projections from the SON and PVN to specific brain regions involved in cardiovascular control, and their possible involvement in baroreflex mechanisms is discussed. However, there is little unequivocal evidence that AVP is the main neurotransmitter utilized by descending projections from PVN to NTS and DMX. While, in some situations, circulating endogenous AVP exerts cardiovascular effects, details of its putative influences on baroreflex mechanisms are lacking.  相似文献   
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