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Isolated patellofemoral arthritis is an increasingly recognized entity, and is usually associated with previous patellofemoral dysplasia or instability. Patellofemoral arthroplasty (PFA) has evolved significantly in recent years, both in terms of implant design and importantly in the understanding of appropriate patient selection. This review outlines the indications and investigations for PFA, provides a brief history of the development of contemporary implants, and presents the clinical outcomes for the prostheses most commonly used in the UK. In addition, it provides a detailed surgical technique for implantation of an onlay implant, with tips on how to optimize patellofemoral biomechanics and thus achieve a consistently good outcome.  相似文献   
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In meningitis, the cerebrospinal fluid contains high levels of innate immune molecules (e.g. complement) which are essential to ward off the infectious challenge and to promote the infiltration of phagocytes (neutrophils, monocytes). However, epithelial cells of either the ependymal layer, one of the established niche for adult neural stem cells, or of the choroid plexus may be extremely vulnerable to bystander attack by cytotoxic and cytolytic complement components.  相似文献   
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Agenesis of the Gallbladder Revisited Laparoscopically   总被引:1,自引:0,他引:1  
Gallbladder agenesis is an extremely rare disease. Necropsy incidence has been reported to be 0.016%. Failure lo locate the gallbladder at the time of a planned cholecystectomy can be very challenging. We report such a case during a laparoscopic cholecystectomy. The indication for surgery in these patients are complaints of gallbladder symptoms along with a false-positive ultrasound study. During exploration, an abnormal location of the gallbladder has to be excluded. Ectopic gallbladder locations include intrahepatic, lesser omentum, retroperitoneal, retrohepatic, within the falciform ligament, retroduodenal, and retrohepatic areas. Thorough exploration and cholangiography are essential. Embryologically, the gallbladder and cystic duct arise from the caudal portion of the hepatic bud. All of the previously reported cases of gallbladder agenesis have shown an absence of both the gallbladder and cystic duct. We report an embryological oddity wherein a patent cystic duct was found along with an agenetic gallbladder. This is the first case report of this finding, along with this being the first absent gallbladder discovered laparoscopically.  相似文献   
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Sonoelasticity imaging of prostate cancer: in vitro results   总被引:2,自引:0,他引:2  
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BACKGROUND: House-dust mites in clothing and bedding are the source of major allergens. Based on studies of Dermatophagoides pteronyssinus only, weekly washing in hot water is recommended to kill dust mites and remove allergens from clothing and bedding. However, in the United States, washing is most often done in warm or cold water, and other mite species are involved. OBJECTIVE: The purpose of this study was to investigate the lethal effects of various temperatures of hot water alone and hot, warm, and cold water containing detergents and chlorine bleach on Dermatophagoidesfarinae, D. pteronyssinus, and Euroglyphus maynei. METHODS: Mites were soaked in test solutions at various temperatures and for various lengths of time, allowed time to recover, and then analyzed for survival. RESULTS: D. farinae was the most temperature-sensitive and chlorine bleach-sensitive of the three species. In 50 degrees C water alone, 100% mortality for D. farinae was obtained in 10 minutes, whereas most D. pteronyssinus and E. maynei survived. However, 53 degrees C-soaks for 12 and 5 minutes were needed to kill all D. pteronyssinus and E. maynei, respectively. Laundry detergents at their recommended and doubled concentrations and chlorine bleach generally increased mite mortalities over water alone for the three species. Soaking for 4 hours in warm water containing various detergents alone induced mortalities of 19 to 50%, 2 to 35%, and 14 to 46% for D. farinae, D. pteronyssinus, and E. maynei, respectively. CONCLUSIONS: Washing bed linens weekly in warm water with a 4-hour presoak containing most detergents and bleach will kill most D. farinae and, depending on the detergent brand, moderate numbers of D. pteronyssinus. Four-hour soaks in warm water containing the recommended concentrations of various detergents alone also kills moderate numbers of D. farinae, D. pteronyssinus, and E. maynei. Therefore, the cumulative effect of weekly washing with long presoaks should significantly reduce mite levels over time in bed linens, particularly when mattresses and pillows are encased to prevent reinfestation.  相似文献   
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Laboratory routines cause animal stress.   总被引:8,自引:0,他引:8  
Eighty published studies were appraised to document the potential stress associated with three routine laboratory procedures commonly performed on animals: handling, blood collection, and orogastric gavage. We defined handling as any non-invasive manipulation occurring as part of routine husbandry, including lifting an animal and cleaning or moving an animal's cage. Significant changes in physiologic parameters correlated with stress (e.g., serum or plasma concentrations of corticosterone, glucose, growth hormone or prolactin, heart rate, blood pressure, and behavior) were associated with all three procedures in multiple species in the studies we examined. The results of these studies demonstrated that animals responded with rapid, pronounced, and statistically significant elevations in stress-related responses for each of the procedures, although handling elicited variable alterations in immune system responses. Changes from baseline or control measures typically ranged from 20% to 100% or more and lasted at least 30 min or longer. We interpret these findings to indicate that laboratory routines are associated with stress, and that animals do not readily habituate to them. The data suggest that significant fear, stress, and possibly distress are predictable consequences of routine laboratory procedures, and that these phenomena have substantial scientific and humane implications for the use of animals in laboratory research.  相似文献   
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