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1.
The short section of the urethra that passes through the urogenital diaphragm is termed the membranous urethra. It is accompanied by several vessels and nerve fibers. In surgery on the membranous urethra the perineal body is of crucial importance, and precise knowledge of the course of the urethra through the pelvic floor is essential. Furthermore, the relationship between the membranous urethra and its accompanying structures is of great importance. These include the branches of the internal pudendal artery, the prostatic venous plexus and the cavernous nerves coursing ventrally from the pelvic plexus. The nerves supplying the membranous urethra were studied in fetuses with the help of a magnifying lens. The results of the dissections are documented by histological sections, photographs and paintings.  相似文献   
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In order to evaluate the effect of concurrent administrationof areca nut and sodium nitrite, a long-term feeding study wasconducted with 120 Syrian hamsters. The animals were dividedinto four treatment groups, each consisting of 15 males and15 females, and received 2 g/kg diet of sodium nitrite (groupI), 20 g/kg diet of powdered areca nut (group II), 2 g/kg dietof sodium nitrite plus 20 g/kg diet of areca nut (group III)or powdered diet only (group IV) throughout their lifetime.Urine samples from all groups were analysed for N-nitrosonipecoticacid (NNIP), a major urinary metabolite of areca-nut-derivednitrosamines. NNIP was only detected in the urine of hamstersfed nitrite plus areca nut (concentration: 1.9±0.9 ng/mlurine), indicating that areca nut alkaloids underwent in vivonitrosation to form arecanut-specific nitrosamines. The totaltumour response was not significantly elevated in groups IIand III. Hamsters of group III had a markedly, but also insignificantlyhigher frequency of malignant tumours than those of the othergroups, with a statistically significant increase in malignantlymphomas in the males. Although limited by the low number ofanimals per group, these results indicate that exposure to nitritetogether with areca nut constituents appears to enhance therisk of developing malignancies.  相似文献   
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For cardio-pulmonary resuscitation there are standardized treatment concepts, but there have been few prospective investigations examining the efficacy of prehospital advanced trauma life support and its effect on the outcome in patients with severe head injury and multiple trauma treated within the German emergency system. The results of this study underline the importance of intensive prehospital treatment and highlight some problems that should be taken into account in future in the training of emergency physicians. Methods. A total of 179 patients with cerebral trauma were investigated. Data obtained included demographic and logistic data of the patients and the emergency physicians, diagnoses and treatment at the scene of the accident and state of the patient on admission in each case. Having divided the patients into three groups by severity of the trauma, we distinguished between sufficient and insufficient treatment and assessed infusion therapy, ventilatory support, positioning and immobilization, and analgesic and sedative therapy. For statistical analysis of the data we used χ2-test and Fisher's exact test. P<0.05 was considered significant. Results. There were 102 patients who had sustained a cerebral trauma without other life-threatening lesions (score 1), 40 with multiple trauma (score 2) and 37 with multiple trauma (score 3). On average 2.4?IV lines were established and the patients received 1186±765?cc of crystalloid in addition to 801±411?cc of colloid fluids. In all groups, patients who received adequate infusion therapy had a better outcome; even in the group with score 1 significantly fewer had a fatal outcome. In all, 167 (93%) patients had endotracheal tubes placed, and in 150 cases (84%) ventilatory therapy was considered sufficient. The proportion of score 1 patients with sufficient ventilatory support who had a fatal outcome was significantly lower than that in the group with insufficient treatment. In patients with multiple trauma we could not separate the benefits of sufficient respiratory therapy and infusion therapy. In only 54% of the cases a vacuum mattress was used and in only 41% the patients were positioned with the upper part of the body elevated by 30°. These were 28 patients (16%) who received neither analgesics nor sedatives. Regardless of the quality of prehospital treatment of isolated head injury, a Glasgow Coma Scale (GCS) score lower than 5 involved a very high mortality and all patients with a GCS score of 9 or more survived. In the group with GCS scores between 5 and 8, however, significantly more of the patients who received adequate treatment survived (82.5% vs 40%). Conclusions. The present study confirms that sufficient advanced trauma life support can improve the outcome of trauma victims with cerebral trauma. Adequate infusion and respiratory therapy reduce the mortality among such patients significantly. In patients with multiple trauma a clear positive effect of generous infusion therapy also is evident. The clearest effect of sufficient prehospital treatment is seen in patients with isolated cerebral trauma and a GCS score between 5 and 8. These results demonstrate the importance of advanced trauma life support and show emphatically that the so-called scoop-and-run strategy should be abandoned when resources are available for extended preclinical emergency treatment. On the other hand, we detected some problem areas in the prehospital treatment of trauma victims, such as positioning, immobilization and drug therapy with analgesics and sedatives. These findings allow us to pinpoint specific points that should be stressed in the training of emergency physicians and paramedics.  相似文献   
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The metabolism of chemical carcinogens was investigated in liverpreparations from 28 captive woodchucks (Marmotamonax). Of these,23 were naturally infected with the wood-chuck hepatitis virus(WHV), and eight also had primary hepatocellular carcinoma (PHC).Twenty-nine parameters were investigated in liver subcelhilarfractions, including cross-reactivity with HBsAg, and biochemicalparameters, such as -glutamyl transpeptidase, cytochrome P-450and mirosomal monooxygenases (aryl hydrocarbon hydroxylase,ethodycoumarin and ethoxyresorufin deethylases, amino-pyrineand dimethylnitrosamine demethylases, and testosterone 7-and16ß- and 6ß-hydroxylases), uridine 5'-diphos-phoglucuronosyltransferase, GSH and related enzymes (peroxidase, reductaseand S-transferase), as well as other cytosolic enzyme activities(glucose 6-phosphate and 6-phosphogluconate dehydrogenases,NADPH- and NADH-dependent diaphorases, and DT diaphorase). Inaddition, liver preparations were used in order to quantifythe metabolic activation into bacterial mutagens of five procarcinogens(aflatoxin B1, the pyrolysis products Trp-P-2 and MelQ, 2-aminofluoreneand dimethylnitrosamine) and the decrease of potency of threedirect-acting mutagens (sodium di-chromate, ICR 191 and 4-nitroquinoline1-oxide). WHV infection produced a significant stimulation ofcarcinogen metabolism, as shown by the simultaneous change indetoxification parameters (GSH depletion) and activation indices(enhancement of microsomal monooxygenases and of pro-carcinogenactivation into mutagenic metabolites). There were no significantdifferences between WHV-positive samples from animals, withoutPHC and the noncancerous tissue of PHC-bearing animals, whereasa decrease of both activation and detoxification indices wasrecorded in the turmorous tissue. There was a considerable interindividualvariability among WHV carriers, which was tentatively ascribedto genetic factors. Pregnancy was the only known factor influencingthe results in WHV carriers. However, even by excluding pregnantanimals, the effects on carcinogen metabolism produced by WHVinfection were still statistically significant. These results,together with previous data obtained in humans, revealed thatmetabolic factors may play a role in the synergism between viralhepatitis and chemical hepato-carcinogens in the etiopathogenesisof PHC.  相似文献   
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Summary Disruption of the gene for the adhesion molecule on glia (AMOG, the 2-subunit of the Na, K-ATPase) in mice results in swelling and subsequent degeneration of astrocyte endfeet in the brainstem and in cell death of photoreceptor cells in the retina. In the present study, we demonstrate that photoreceptor cells in the mutant develop normally during the first postnatal week. Compared to wild-type mice, a slightly increased density of degenerating photoreceptor cells became apparent in 9-day-old mutants and numerous degenerating photoreceptor cells were present in the retina of 16-day-old AMOG/2-deficient mice.In situ labelling of degenerating cells by terminal dUTP nick end labelling and electron microscopic analysis revealed apoptotic cell death of photoreceptor cells. Massive degeneration of photoreceptor cells in the mutant at postnatal day 16 correlated with elevated levels of glial fibrillary acidic protein in retinal astrocytes and with expression of this protein by Müller cells. No evidence was found for degeneration of other retinal cell types or for glial cell death in the optic nerve. Our observations demonstrate that the pathological death of cells induced by disruption of the AMOG/2 gene results from activation of an intrinsic death program, similar to what has been shown to occur during normal development.  相似文献   
9.
Microdeletion syndromes are commonly transmitted as dominant traits and are frequently associated with variably expressed pleiotropic phenotypes. Nonlethal homozygous microdeletions, on the other hand, are very rare. Here, we delineate the fifth and so far largest homozygous microdeletion in nonmalignancies of approximately 400 kb on chromosome 4q11-q12 in a large consanguineous East-Anatolian family with six affected patients. The deleted region contains the beta-sarcoglycan gene (SGCB), the predicted gene SPATA18 (spermatogenesis associated 18 homolog) and several expressed sequence tags. Patients presented with a severe and progressive Duchenne-like muscular dystrophy phenotype, a combination of hyperlaxity and joint contractures, chest pain, palpitations, and dyspnea.  相似文献   
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We describe two unrelated patients with cytogenetically visible deletions of 21q22.2-q22.3 and mild phenotypes. Both patients presented minor dysmorphic features including thin marfanoid build, facial asymmetry, downward-slanting palpebral fissures, depressed nasal bridge, small nose with bulbous tip, and mild mental retardation (MR). FISH and molecular studies indicated common deleted areas but different breakpoints. In patient 1, the breakpoint was fine mapped to a 5.2 kb interval between exon 5 and exon 8 of the ETS2 gene. The subtelomeric FISH probe was absent on one homologue 21 indicating a terminal deletion spanning approximately 7.9 Mb in size. In patient 2, the proximal breakpoint was determined to be 300-700 kb distal to ETS2, and the distal breakpoint 2.5-0.3 Mb from the 21q telomere, indicating an interstitial deletion sized approximately 4.7-7.3 Mb. The 21q- syndrome is rare and typically associated with a severe phenotype, but different outcomes depending on the size and location of the deleted area have been reported. Our data show that monosomy 21q of the area distal to the ETS2 gene, representing the terminal 7.9 Mb of 21q, may result in mild phenotypes comprising facial anomalies, thin marfanoid build, and mild MR, with or without signs of holoprosencephaly.  相似文献   
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