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11.
PD Dr. T. F. Schwarz M. D. Prof. H. Nsanze M. D. Prof. A. M. Ameen M. D. 《Infection》1997,25(6):364-367
Summary Crimean-Congo haemorrhagic fever (C-CHF) re-emerged recently in the United Arab Emirates. The clinical outcome of 11 cases of viral haemorrhagic fever patients admitted to hospital between June 1994 and January 1995 is described. Four cases were laboratory confirmed retrospectively as C-CHF, the other patients were diagnosed likely to have the same disease on epidemiological and clinical grounds. In 72.7% of the patients, infection was fatal. Symptoms started 3.5 days before hospitalization. On admission, 81.8% of patients had high fever, 45.5% were vomiting, 63.6% had diarrhoea, 45.5% had haemorrhagic signs, and 18.2% had throat pain. Fatalities occurred 6.8 days after admission. Survivors were hospitalized for 9.3 days. Nosocomial transmission was not observed. 相似文献
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Assault-injured Adolescents Presenting to the Emergency Department: Causes and Circumstances 总被引:1,自引:0,他引:1
14.
Feeding behavior in Aplysia fasciata and A. oculifera is modified by pairing the behavior with reinforcing consequences. Successful and unsuccessful attempts to transfer food from the buccal cavity to the crop act as positive and negative reinforcers, respectively. A number of changes in feeding behavior occur as a result of pairing of feeding with the negative reinforcer: feeding responses become less effective in leading to the entry of food into the buccal cavity; when food does enter the buccal cavity, it exits sooner; swallowing responses after food entry are less likely to occur; Aplysia eventually cease responding to food. Pairing successful transfer of food into the crop with feeding behavior produces opposite effects. Behavioral change is specific to pairing, as shown by lack of change when reinforcement is explicitly unpaired with feeding behavior. Behavioral change is specific to foods with a particular taste and texture; generalization to alternate foods was not observed. In spite of cessation of feeding, animals remain aroused, as shown by low response latency to alternate foods. Memory of response change persists for at least 48 hr. 相似文献
15.
Development of cytochrome P-450-altered preneoplastic and neoplastic lesions during nitrosamine-induced hepatocarcinogenesis in the rat 总被引:3,自引:0,他引:3
The expression of four cytochrome (cyt.) P-450 isoenzymes has been studied in preneoplastic and neoplastic lesions during the course of nitrosamine-induced hepatocarcinogenesis in the female Wistar rat. Following exposure to diethylnitrosamine (50 or 100 ppm in the drinking water) for 10 days, animals were taken sequentially, and the livers were analyzed for the evolution of adenosine triphosphatase deficient focal lesions. These lesions were subdivided into different phenotypes with regard to their cyt. P-450 isoenzyme expression using serial frozen sections. Our results demonstrate that about 40% of the adenosine triphosphatase-deficient lesions show concomitant alterations in their cyt. P-450 isoenzyme contents. Of these lesions, islets which are characterized by decreased levels of at least three cyt. P-450 isoenzymes show a dramatic increase in their volumetric fraction of liver tissue with progression of time. Although only very few lesions express this phenotype, the contribution to the volumetric fraction of islet tissue raises from about 2% at 10 weeks to about 60% at 35 weeks after cessation of diethylnitrosamine treatment. By contrast, lesions which express less than two alterations in cyt. P-450 isoenzyme levels develop relatively slowly. Similar results were obtained when animals were exposed continuously to diethylnitrosamine for a period of up to 8 weeks. Following treatment of islet-bearing animals with phenobarbital, an induction of cyt. P-450 isoenzymes and NADPH-cyt. P-450-reductase was observed within preneoplastic and neoplastic lesions. This induction was most pronounced in large, expansively growing nodules, a type of lesion which displayed decreased levels of these enzymes in livers of animals not treated with phenobarbital. The elevation of the cyt. P-450 isoenzymes disappeared within 2 to 3 weeks after cessation of inducer treatment. Our results indicate that a high proportion of rapidly growing lesions has assumed a constitutive deficiency in cyt. P-450 isoenzyme expression during nitrosamine-induced hepatocarcinogenesis. This deficiency, however, is not an irreversible quality, since individual cyt. P-450 isoenzymes can be markedly induced by treatment with an enzyme inducer like phenobarbital. Thus, the observed decrease in cyt. P-450 expression during development of malignancy does not result from alterations in the cyt. P-450 encoding structural genes but may rather be related to abnormalities in the function of regulatory systems of a higher order which may play a central role in the maintenance of cell homeostasis. 相似文献
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From 1930 to 1989 postoperative rupture of abdominal wound occurred in 0.42 per cent (n = 82) in the Department of Obstetrics and Gynaecology of the University of Rostock. 60 per cent of the patients were younger than 50 years. Patients of reduced general condition and anaemia were predisposed to this complication. We observed postoperative alterations of the respiratory tract in 13 per cent and alterations of the gastro-intestinal tract in 20 per cent which lead to increased intra-abdominal pressure. We observed postoperative wound rupture only in 8 cases after Pfannenstiel's incision, but all other times after median section, predominantly during the 7th and 12th postoperative day. All patients were treated by secondary suture, immediately. 8 patients came to death, three of them had no direct link to wound rupture. For prophylaxis the use of non-absorbable suture material, safety sutures, intraoperative blood and protein substitution and prevention of affections of the respiratory system and gastrointestinal tract are recommended. 相似文献
18.
Ping Li Edward M Schwarz Regis J O'Keefe Lin Ma Brendan F Boyce Lianping Xing 《Journal of bone and mineral research》2004,19(2):207-213
To address the controversy of whether TNFalpha can compensate for RANKL in osteoclastogenesis in vivo, we used a TNFalpha-induced animal model of inflammatory arthritis and blocked RANKL/RANK signaling. TNFalpha increased osteoclast precursors available for RANK-dependent osteoclastogenesis. RANK signaling is not required for the TNFalpha-stimulated increase in CD11b(hi) osteoclast precursors but is essential for mature osteoclast formation. INTRODUCTION: Although critical roles of TNFalpha in inflammatory arthritis and RANKL in bone resorption have been firmly established, a central controversy remains about the extent to which TNFalpha can compensate for RANKL during osteoclastogenesis and the stage at which RANK signaling is required for osteoclastogenesis. Here, we used the human TNFalpha transgenic mouse model (TNF-Tg) of erosive arthritis to determine if there are both RANK-dependent and -independent stages of osteoclastogenesis in TNFalpha-induced erosive arthritis. MATERIALS AND METHODS: Osteoclastogenesis and osteoclast precursor (OCP) frequency were analyzed using histology, fluorescence-activated cell sorting (FACS), and cell culture from (1) TNF-Tg mice treated with the RANKL antagonist, RANK:Fc, or (2) TNF-Tg X RANK -/- mice generated by crossing TNF-Tg mice with RANK-/- mice. RESULTS: Treatment of TNF-Tg mice, which have increased OCPs in their spleens, with RANK:Fc dramatically reduced osteoclast numbers on the surface of their arthritic joints and within their bones, but did not decrease CD11b(hi) OCP numbers in their spleens. Long-term RANK:Fc administration alleviated joint erosion. Furthermore, TNF-Tg x RANK -/- mice had severe osteopetrosis, no osteoclasts, and no joint erosion, but increased CD11b(hi) precursor numbers that failed to form mature osteoclasts in vitro. CONCLUSION: RANK signaling is essential for mature osteoclast formation in TNFalpha-mediated inflammatory arthritis but not for the TNFalpha-induced increase in CD11b(hi) OCP that subsequently can differentiate into osteoclasts in inflamed joints. 相似文献
19.
Ignatius Gerardo E Zarraga Ernst R Schwarz 《Journal of the American College of Cardiology》2007,49(1):1-14
Since their approval in 1998, the popularity of selective cyclooxygenase-2 (COX2) inhibitors has swung from a domination of drug sales to serious disputes about their cardiovascular safety. Despite the numerous studies on COX2 inhibitors that have emerged, drawing conclusions about their cardiovascular safety has been complicated by conflicting results, underpowered clinical trials, and the lack of a placebo group and use of post hoc analyses in many trials. Nonetheless, certain conclusions can be made with reasonable accuracy. This review addresses the controversy in 3 segments. It begins with a discussion of the several mechanisms proposed to explain how selective COX2 inhibition impacts the cardiovascular system. This is followed by a recount of the several clinical studies that delved into the cardiovascular outcomes associated with COX2 inhibitors. Finally, answers to key questions are provided to assist the clinician in devising a systematic approach to the risk-benefit analysis of COX2 inhibitors in actual practice. 相似文献
20.
T. Hammen F. Kerling M. Schwarz A. Stadlbauer O. Ganslandt B. Keck B. Tomandl A. Dörfler H. Stefan 《European journal of neurology》2006,13(5):482-490
Up to 30% of patients with temporal lobe epilepsy (TLE) remain without remarkable changes in MRI. In this study we investigated the role of (1)H-MR spectroscopy ((1)H-MRS) in lateralizing the affected hemisphere in the mentioned patient group. Twenty-two consecutive patients diagnosed with TLE were investigated by high resolution MRI and (1)H-MRS. We examined the incidence and diagnostic accuracy of temporal metabolite alterations determined by Linear Combination of Model Spectra (L C Model) via water reference. Metabolite values of each hemisphere of TLE patients were compared with healthy controls. Results of metabolite alterations were related to intensive video EEG focus localization. Reduction of N-acetylaspartate + N-acetylaspartyl-glutamate (tNAA) in the affected hemisphere revealed identification in six of nine patients (66%) with unilateral TLE. Group comparison revealed a significant reduction of tNAA (6.1+/-0.8*) in the involved temporal lobe compared with controls (6.67+/-0.4*, P=0.026). Choline levels were significantly increased in the affected hemisphere (1.42+/-0.17*) compared with healthy controls (1.22+/-0.17*, P=0.035). The results of our study show that (1)H-MRS is able to identify the affected hemisphere of MRI negative TLE patients and can be used as an additive tool in multimodal focus localization. 相似文献