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71.
OBJECTIVE: A retrospective review of appendectomies performed at the University of Kansas Medical Center between January 1, 1989, and January 1, 1994, was conducted. In addition, the literature evaluating effectiveness of incidental appendectomy in preventing future operation and morbidity from appendicitis was reviewed. The results of the two reviews were analyzed to formulate guidelines for the appropriateness of performing incidental appendectomy in association with other operative procedures. METHOD: A retrospective review of results of appendectomies performed in 460 patients at the University of Kansas Medical Center with analysis of operative findings, pathology of the removed appendix and operative complications was performed. These results were compared with those of a systematic review of the literature utilizing a Medline search relating to the subject of incidental appendix removal. RESULTS: Two hundred sixty-one incidental appendectomies were performed in this study of 460 patients (60%). The procedure was most commonly performed with total abdominal hysterectomy (56%), followed by oophorectomy (15%) and exploratory laparotomy (11%). Morbidity was minimal at all ages. Microscopic pathology was found in 25% of the cases. CONCLUSION: The data from the current survey and literature review support incidental removal of the appendix in the young patient (< 35 years old). In patients 35-50 years old the literature is controversial, and the patient's clinical condition and judgment of the operating surgeon should determine whether incidental appendectomy should be performed. However, routine incidental appendectomy cannot be justified in patients greater than age 50.  相似文献   
72.
A comparison of transplant outcomes in peritoneal and hemodialysis patients   总被引:7,自引:0,他引:7  
BACKGROUND: Studies examining the effect of pre-transplant dialysis modality on graft and patient survival after kidney transplantation have produced conflicting results. Therefore, we studied the effects of pre-transplant dialysis modality on outcomes in a large United States cohort. METHODS: We compared rates of transplantation between peritoneal dialysis and hemodialysis patients from the years 1995 to 1998 in the United States (N = 252,402) and outcomes after transplantation (N = 22,776), using data from the Centers for Medicare and Medicaid Services. RESULTS: In a Cox proportional hazards analysis that was adjusted for multiple patient characteristics, kidney transplantation was 1.39 (95% CI = 1.35 to 1.43) times more likely in peritoneal dialysis vs. hemodialysis patients (P < 0.0001). Over the entire follow-up period, the adjusted risk for death-censored graft failure was 1.15 (1.04 to 1.26) times higher in peritoneal dialysis vs. hemodialysis (P < 0.05), but mortality and overall graft failure rates were not different. Pre-transplant dialysis modality did not affect outcomes for patients who survived with a functioning kidney for at least 3 months. However, in adjusted Cox analyses restricted to the first 3 months, peritoneal dialysis was associated with a 1.23 (1.09 to 1.39) times higher risk for early graft failure (P < 0.001) and a 1.33 (1.16 to 1.53) times higher risk for death-censored graft failure (P < 0.001). Peritoneal dialysis patients, however, were seen to have a lower incidence of delayed graft function. In a smaller sample of patients with data on causes of early graft failure, graft thrombosis was more commonly listed as a cause of graft failure among peritoneal dialysis patients, 41% (64/156), compared to hemodialysis patients, 30% (106/349), P < 0.05. CONCLUSIONS: Kidney transplantation is more frequent in peritoneal dialysis than in hemodialysis patients, and transplantation in peritoneal dialysis patients is more frequently associated with early, but not late, graft failure. Delayed graft function was less common in peritoneal dialysis patients but this potential benefit appears to be offset by other factors which are associated with early graft loss. Additional studies are needed to determine what factors may help understand this early risk of graft failure.  相似文献   
73.
Osteoporosis is a systemic metabolic disease resulting in low bone mass, which increases the risk for fracture. Evidence suggests that lifestyle changes to prevent or delay development of osteoporosis should be implemented throughout the life span. The purpose of this study was to evaluate the effectiveness of a multidisciplinary primary osteoporosis prevention program for community-dwelling women aged 25 to 75 years to determine if osteoporosis prevention program participants (treatment group) increased their knowledge of osteoporosis, calcium intake, and exercise compared with a control group. Other outcomes included participants' willingness to adopt lifestyle changes and ability to view themselves as able to make behavioral changes. Subjects in the treatment group versus control subjects increased their knowledge of osteoporosis over time. At posttest, subjects in the treatment group were more likely to be planning to change calcium intake, and at follow-up, they were more likely to be changing their calcium intake. No other group differences were found between the two groups. These findings suggest that a multidisciplinary education program may have an impact on knowledge and behaviors that may help to delay the development of osteoporosis.  相似文献   
74.
Complete genital or vaginal prolapse affects a large number of middle-aged to elderly females. Satisfactory correction of prolapse with maintenance of vaginal patency has been a challenge to the pelvic surgeon for many years. We present a retrospective review of 147 patients undergoing abdominal sacral colpopexy using dacron graft or expanded polytetrafluoroethylene. The anatomical basis of repair, operative technique, and results are described. Ninety-three percent of the patients experienced long-term success over 5 years, including those with previous failed repairs. Both short- and long-term complication rates were acceptable. Only four patients experienced graft erosion, and only one of those had recurrent prolapse. Abdominal sacral colpopexy offers those affected with genital prolapse an opportunity for long-term relief, with maintenance of a patent vagina.  相似文献   
75.
The distribution of some cholecystokinin (CCK) systems in the rat brain is reviewed focusing on mesencephalic dopamine neurones which coexpress CCK and, in particular, on cortico-striatal CCK neurones which probably have glutamate as their co-transmitter. Functional studies based on the effect of several CCK(B) antagonists on phencyclidine-induced motility suggest that CCK is involved in locomotor behaviour causing inhibition in phencyclidine-treated habituated rats. In contrast, in unhabituated rats CCK stimulates exploratory behaviour. These effects may be related to the cortico-striatal CCK/glutamatergic pathway. Moreover, these studies provide evidence for endogenous release of a neuropeptide with behavioural consequences.  相似文献   
76.
77.
The in vitro and in vivo genotoxicity of tamoxifen is well documented but the underlying mechanism of this genotoxicity is only poorly understood. Tamoxifen is known to form adducts with DNA and it has been suggested that DNA intercalation may facilitate this covalent interaction. However, the low aqueous solubility of tamoxifen has made it difficult to demonstrate DNA intercalation by standard physico-chemical methods. In the present paper, we have employed the Chinese hamster V79 cell-based assay for the detection of DNA intercalation and report that tamoxifen, indeed, appears to have DNA intercalative properties. A partial structure activity relationship evaluation suggests that the N-dimethyl group of tamoxifen enhances intercalation.  相似文献   
78.
The spinosyns are a novel family of fermentation-derived natural products that exhibit potent insecticidal activities. Spinosad, a naturally-occurring mixture of spinosyn A and spinosyn D, has successfully established its utility for crop protective applications in the agrochemical field. Potential applications of this unique chemical family of macrolides also have been investigated in the field of animal health. Applications for the control of blowfly strike and lice on sheep have now been commercially developed and registered in Australia and potential applications for the control of ectoparasites on cattle are being studied.  相似文献   
79.
Taxol (paclitaxel), a complex diterpene obtained from Taxus brevifolia and its semisynthetic analogue Taxotere are two of the most important new drugs for cancer chemotherapy. Their mechanism of cytotoxic action involves stabilization of microtubules leading to mitotic arrest. A similar mechanism has been proposed for an expanding set of other natural products, for instance, the epothilones, eleutherobin, the sarcodictyins, discodermolide, laulimalide, Rhazinilam, WS9885B, certain steroids and a group of polyisoprenyl benzophenones. In this review, we focus on the conformations of small molecule microtubule (MT) stabilizing compounds which have been isolated or synthesized and subjected to structural analysis. NMR and fluorescense spectroscopies, X-ray crystallography, high resolution microscopy (electron crystallography) and theoretical calculations comprise the most common methods used in this context. In particular, we describe how the structures were determined and with what accuracy. We also discuss the conformational diversity apparent from the three dimensional structures and compare the various proposals for bioactive conformations at the target MT binding sites. Of critical importance are the recently disclosed models for Taxol and its biomimetics binding to beta-tubulin. Several different conformational schemes derived from both pharmacophore construction and modeled protein ligand complexes are compared and critically evaluated. Although full consensus has yet to be reached, emphasis is placed on pharmacophore models for the various anti-MT agents that are internally consistent and encompass more than one structural class.  相似文献   
80.
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