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261.
A retrospective study was conducted to evaluate the impact of laparoscopic surgery on activity in general and digestive surgery. From May 1990 to December 1994, 2256 laparoscopic procedures were performed for cholecystectomy (36%), appendicectomy (20.4%) or inguinal hernia (19.8%). 23.2% of all procedures performed in 1994 were done laparoscopically. The use of laparoscopy did not, in our experience, added any new indications from 1988 to 1994. The conversion rate was 8.15%. 24% of the conversion cases could not be predicted. Mortality was 0.18% and 1.19% of the patients had to undergo a second operation due to complications of laparsocopic surgery. The impact of laparoscopic procedures, 7 years after the first laparoscopic cholecystectomy has been great. The results of this surgical technique must be evaluated to determine its medical and economic impact.  相似文献   
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Carotenoids are thought to act as antioxidants in vivo, decreasing oxidative damage to biomolecules and thus protecting against coronary heart disease and cancer. However, human intervention studies with beta-carotene have given equivocal results in terms of cancer incidence. In an alternative molecular epidemiological approach, we have employed the 'comet assay' (single cell alkaline gel electrophoresis) to measure strand breaks, oxidized pyrimidines and altered purines in the DNA of lymphocytes from volunteers supplemented with alpha/beta-carotene, lutein, lycopene or placebo. In addition, we measured concentrations of the main serum carotenoids, and vitamins E and C, by HPLC. We report a significant negative correlation between basal concentrations of total serum carotenoids and oxidized pyrimidines. A similar correlation was seen between individual carotenoids (notably lutein and beta-carotene) and oxidized pyrimidines. However, carotenoid supplementation did not have a significant effect on endogenous oxidative damage. This suggests that there are some factors in the basal diet, probably found in fruit and vegetables, that decrease oxidative damage to DNA. In this case, basal serum carotenoids may simply be markers of consumption of fruit and vegetables, they themselves having little or no protective value.  相似文献   
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Sex reversed mice are XX males carrying on one of their X chromosomes a translocation of the sex determining region of the Y (Cattanach's Sxr factor). The phenotype corresponds to the Klinefelter syndrome in man. The X linked Tfm (testicular feminization) mutation in the mouse is a frame shift in the androgen receptor gene leading to complete androgen insensitivity. Due to random X inactivation, sex reversed mice heterozygous for Tfm, are mosaics composed of a variable proportion of androgen insensitive X Tfm and androgen sensitive X+ wildtype cells. In the intersexual genital tract, Tfm cells are maintained as undifferentiated cells in the epididymal duct. To the distorted prostate lobes and bulbourethral glands they contribute some lobules of indifferent urethral glands. A large contribution of Tfm cells allows downgrowth of Wolffian and Müllerian ducts to form a vagina. In the external genitalia the stimulatory effect of testosterone is reduced leading to various degrees of feminization correlating with the proportion of Tfm cells present. In the mosaics effects of testosterone, mediated by local growth factors from the wildtype to the Tfm cells, can be distinguished from direct effects expressed only in the wildtype cells. Mediated effects are embryonic induction and morphogenesis of male organs and postnatal maintenance of organ structure and proliferation. The direct effect is cellular differentiation.  相似文献   
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Operative stroke complicating carotid endarterectomy is traditionally treated by reexploration of the operative site to correct a potentially causative lesion; however, attempts are not made to diagnose or treat the intracranial arterial occlusion. A 65-year-old man had a right hemiplegia during a left carotid endarterectomy that was caused by premature reversal of heparin, which resulted in thrombosis of his left anterior cerebral artery. On reexploration, the patient was treated with a 1-hour infusion of 1 million U urokinase through an indwelling carotid shunt. A repeat arteriogram demonstrated patency of the left anterior cerebral artery, with complete clot dissolution and resolution of the right hemiplegia on awakening. Natural history studies of stroke and prospective, angiographically controlled clinical trials of intraarterial thrombolytic therapy for acute stroke support the use of intraoperative intraarterial infusion of urokinase as part of a therapeutic approach to patients who have an ischemic stroke during carotid endarterectomy.  相似文献   
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The CNS is frequently involved in human immunodeficiency virus (HIV) infection. In recent studies using proton magnetic resonance spectroscopy, investigators found a significant reduction in N-acetyl aspartate, a metabolic marker of neurons, in late stages of dementia. To further understand the relationship between proton magnetic resonance spectroscopy changes and clinical disease and dementia, we compared 20 HIV-infected patients presenting at varying stages of acquired immunodeficiency syndrome (AIDS) dementia complex and infection to 10 age-matched controls. We found a significant reduction in N-acetyl aspartate/creatine only in patients who had advanced dementia and CD4 counts less that 200/microliter. By contrast, a significant elevation in compounds containing choline was present in patients in the early stages of HIV infection of who had CD4 counts greater than 200/microliter, in patients with normal MRI scans, and in all AIDS dementia complex groups, including subjects with no or minimal cognitive impairment. An elevated choline level also occurred in later stages of HIV infection (CD4 < 200/microliter). Our results suggest that an increase in choline occurs before N-acetyl aspartate decrements, MRI abnormalities, and the onset of dementia, and may therefore provide a useful marker for early detection of brain injury associated with HIV infection.  相似文献   
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Contribution of two cases of renal adenocarcinoma in pediatric patients. Comments on the most updated and relevant aspects of epidemiology, clinical manifestations, diagnosis, treatment, prognosis and follow-up. Comparison to nephroblastoma and renal adenocarcinoma of the adult.  相似文献   
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