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Between January 1983 and December 1985, 305 patients were admitted to our hospital because of bleeding duodenal ulcer. A subgroup of 69 patients aged 50 or above in whom emergency endoscopy showed non-arterial bleeding or signs of recent haemorrhage without a visible vessel entered a prospective therapeutic trial. The patients were randomized to receive either (1) early surgery, implying immediate operation, or (2) expectant management, with surgery reserved only for patients with further haemorrhage. The two groups were homogeneous with respect to age, sex, prior ingestion of ulcerogenic drugs, mode of bleeding, admission haematocrit, number with hypovolaemic shock and number with active bleeding on initial endoscopy. Overall mortality was 8.6 per cent. Mortality in patients submitted to early surgery was five times higher than that in those allocated to expectant therapy (14.7 per cent versus 2.9 per cent; risk ratio 5.07). The results suggest that expectant management is advisable in patients with bleeding duodenal ulcer not bleeding massively and in whom endoscopy does not disclose spurting arterial bleeding or a visible vessel.  相似文献   
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Meyerovitz  MF; Reagan  K; Friedman  PL 《Radiology》1989,171(3):866-868
Posteroanterior (PA) and caudally angulated PA views were obtained in 20 patients undergoing routine coronary arteriography. Although the left main coronary artery (LMCA) was seen well on both views in all patients, the PA-caudal view improved depiction of the LMCA bifurcation in 15 (75%). In addition, the PA-caudal view markedly improved depiction of the circumflex artery, affording optimal depiction of this artery and its branches in 78%-89% of patients. Neither the PA nor the PA-caudal view allowed adequate depiction of the left anterior descending artery. Thus, the PA-caudal view should supplant the PA view in routine coronary arteriography.  相似文献   
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We conducted a prospective, randomized clinical trial among liver transplant patients to assess the efficacy and safety of weekly sulfadoxine/pyrimethamine compared with daily trimethoprim-sulfamethoxazole in the prevention of Pneumocystis carinii pneumonia. The studied drugs were given during 6 months after transplantation. One hundred twenty patients were included. None of the 60 patients receiving weekly sulfadoxine/pyrimethamine developed Pneumocystis carinii pneumonia, whereas two cases (3%) developed among the 60 patients who received trimethoprim-sulfamethoxazole. For both patients, the studied medication had been discontinued several weeks earlier because of adverse effects. No differences were observed in the incidence of adverse effects. We conclude that weekly sulfadoxine/pyrimethamine is as effective and safe as is daily trimethoprim-sulfamethoxazole in the prophylaxis of Pneumocystis carinii pneumonia after liver transplantation.  相似文献   
86.
Paracoccidioides brasiliensis causes paracoccidioidomycosis (PCM) that is one of the most prevalent systemic human mycoses in Latin America. Armadillos show a high incidence of PCM infection and could, therefore, be a natural reservoir for this fungus. In this study were compared the virulence profiles of isolates obtained from nine-banded armadillos (Dasypus novemcinctus) (PbT1 and PbT4) and isolates from PCM patients (Pb265 and Bt83). Pathogenicity was evaluated by fungal load and analysis of colony morphology. Immunity against the fungus was tested by delayed type hypersensitivity test (DTH) and antibody quantification by ELISA. The higher virulence of PbT1 and PbT4 was suggested by higher fungal load in spleen and lungs. Armadillo isolates and Bt83 presented a cotton-like surface contrasting with the cerebriform appearance of Pb265. All isolates induced cellular and humoral immune responses in infected BALB/c mice. DTH reactions were similarly induced by the four isolates, however, a great variability was observed in specific antibody levels, being the highest ones induced by Bt83 and PbT4. The present work confirms that armadillos harbor P. brasiliensis, whose multiplication and induced immunity in experimentally infected mice are heterogeneous, resembling the behavior of isolates from human PCM. This study reinforces the possibility that armadillos play an important role in the biological cycle of this pathogen.  相似文献   
87.
Ergebnisse: Die Eignung von nach Thiel fixierten K?rperspenden als Modelle für Forschung und Lehre in der Mund-Kiefer-Gesichts-Chirurgie wurde untersucht. An Thiel-fixierten K?rperspenden wurden verschiedene operative Zugangswege durchgeführt und die Verwendbarkeit der Pr?parate von Anatomen und Operateuren beurteilt. Diskussion: Es zeigte sich eine hohe Realit?tsn?he in Farbe, Struktur und Konsistenz. Das verwendete Konservierungsverfahren eignet sich in besonderer Weise als Voraussetzung für Forschung und die ?rztliche Aus-, Fort- und Weiterbildung.   相似文献   
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