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2.
Karis Bennett Tanner Vincent Sumathilatha Sakthi-Velavan 《Clinical anatomy (New York, N.Y.)》2022,35(1):52-64
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
3.
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
4.
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
5.
J.-P. Coudereau Marcel Debray Claire Monier Jean-Marie Bourre Henriette Frances 《Psychopharmacology》1997,130(2):117-123
Morphine (8–100 mg/kg IP) induces place preference conditioning in mice. The effect of two different periods of isolation
(15 and 30 days) was examined. Mice isolated for 15 days but not 30 days exhibited place preference conditioning to morphine
(8 mg/kg). After 30 days of isolation morphine could not induce place preference conditioning with the following doses (8, 16, 64, 100 mg/kg).
Social regrouping of male mice previously isolated for 30 days with naive female mice for 15 or 30 days resulted in a reappearance
of the conditioned place preference to morphine (16 mg/kg). The specificity of this associative deficit was examined by testing
learning in isolated compared to non-isolated mice in two distinct settings: escape learning in the Morris water maze and
passive avoidance acquisition and retention. On the Morris water maze isolated mice did not differ from non-isolated mice
regarding place learning, the probe trial or extinction. Isolated mice were unimpaired in passive avoidance acquisition and
retention. It was concluded that the deficits in place preference conditioning were not the result of a global learning impairment
in isolated mice.
Received: 10 April 1996 /Final version: 20 September 1996 相似文献
6.
Frances J. Mather Richard M. Simon Gary M. Clark Daniel D. 《Statistics in medicine》1990,9(9):1118-1118
7.
Probable gas embolism during operative hysteroscopy caused by products of combustion 总被引:8,自引:0,他引:8
Ngozi Imasogie Ron Crago Nicholas A. Leyland Frances Chung 《Journal canadien d'anesthésie》2002,49(10):1044-1047
PURPOSE: Gas embolism is a rare but well documented entity during operative hysteroscopy, with an incidence of 10-50%. Catastrophic outcomes occur at a rate of three in 17,000 procedures. The purpose of this report is to present a non-fatal case of gas embolism probably caused by the gaseous products of combustion. CLINICAL FEATURES: A 50-yr-old woman with a history of menorrhagia was scheduled for hysteroscopy and endometrial ablation and polypectomy. Fifteen minutes into the procedure, with the patient in lithotomy position, 20 degree head down tilt, and breathing spontaneously, a sudden oxygen desaturation occurred from 97% to 87%. The patient's end-tidal carbon dioxide dropped from 46 mmHg to 27 mmHg. The patient's breathing pattern remained normal, respiratory rate remained 11-12 breaths x min(-1) but amplitude of the reservoir bag movement was increased. Cardiovascular variables remained stable. She responded rapidly to 100% oxygen and made an uneventful recovery. Having ruled out other possible causes, we concluded gas embolism was responsible for the fall in oxygen saturation and end-tidal CO(2). CONCLUSION: With all the precautions in place to minimize the likelihood of fluid overload and ambient air embolism occurring, we surmised that products of combustion were the cause of the gas embolism. During endometrial ablation, gaseous products of combustion, mainly carbon dioxide, accumulate. The gases may then contribute to the rise in uterine pressure that occurs as irrigation fluid enters the uterus and this rise in pressure in turn encourages passage of gas into the open venous sinuses. 相似文献
8.
9.
Dinesh Rakheja Payal Kapur Mai P. Hoang Lonnie C. Roy Michael J. Bennett 《Medical hypotheses》2005,65(6):681
Mammalian fatty acid synthase (FASE) overexpression has been shown in a number of human malignancies including colonic adenocarcinoma. Since FASE synthesizes only saturated fatty acids, we hypothesized that cancer cells have a greater proportion of long-chain saturated fatty acids. We studied and found an unequivocal increase in saturated C18 fatty acid (stearic acid) in colonic adenocarcinoma compared to adjacent normal colonic mucosa. The increase is even more striking when measured as a ratio of stearic acid to the unsaturated C18 fatty acids (oleic acid and linoleic acid). This change in fatty acid composition of the cancer cells should significantly alter their physical and biological properties. The increase in relative proportion of saturated fatty acids should make the cancer cells more susceptible to cryodamage and measurement of fatty acid composition of cancer cells may help individualize the temperature for cryotherapy. Also, the lipid alterations may affect the structure and functions of lipid rafts, which may enable the cancer cells to affect signaling mechanisms such as those involved in cell growth and apoptosis. Dietary or therapeutic interventions targeting lipid rafts may thus be an option for cancer treatment. 相似文献
10.
Nonorganic failure-to-thrive is a medical-psychological disorder reflecting lack of growth in an infant without apparent physical causes. Children who fail to thrive as infants are at high risk for developmental delays, personality problems, abuse, and death. This article focuses on environmental failure-to-thrive, describing the behavioral characteristics of the nonthriving infant and the family milieu. Aspects of early environments of NOFT infants are profiled, specific intervention strategies are discussed, and recommendations regarding the promotion of intense, consistent multi-disciplinary intervention strategies are advanced. 相似文献