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Reconstruction of the human atrioventricular node   总被引:6,自引:0,他引:6  
  相似文献   
54.
During 1999-2000, kidney tissues of approximately 15% of 1310 rodents trapped from northeastern provinces of Thailand were tested for the presence of leptospires. Our direct immunofluorescent assay (DFA) for detection of leptospires showed 100% sensitivity and 94% specificity with the culture data. Both methods identified R. norvegicus as the highest source of infection. Among isolated Leptospira, 137 were serotyped by cross agglutinin absorption and/or a microscopic agglutination, and gave some variations and similarities at the serovar level to the DFA results. DFA data demonstrated over half of the positive animals were infected with several serovars of Leptospira interrogans. A subsequent DFA study in Bangkok in 2002 revealed leptospiral infection in 33% of 42 rats and shrews. The most common infecting serovars were Autumnalis and Canicola identified in rural and urban animals, respectively. This finding suggests that wild small mammals may act as important sources of pathogenic leptospires and warrant active surveillance to understand the epidemiology of transmission and control of carrier animals.  相似文献   
55.
OBJECTIVE: We sought to report the unusual distribution of radiation-induced injury to the liver in patients with mesothelioma after extrapleural pneumonectomy and intensity-modulated radiation therapy (IMRT). CONCLUSION: Abnormal hepatic enhancement after extrapleural pneumonectomy and IMRT is common in patients with mesothelioma. Knowledge of the early occurrence and typical location and appearance of IMRT-induced injury can be useful in preventing misinterpretation as metastatic disease or recurrent tumor.  相似文献   
56.
Thinking     
This paper argues that thinking is assumed within nursing education. There are strategies to promote thinking: reflective practice, critical analysis and problem solving. I suggest that by categorising thinking into such boxes there may be a danger of limiting the rich possibilities of simply 'thinking'. The writings of Heidegger (1889-1976) are cited, highlighting the need to 'call' thinking, and to meditate or ponder on the things that matter. The paper comes from research that asked the question 'What calls for thinking in postgraduate education?' Findings reveal examples of teachers and students recalling 'thinking experiences' but also suggest there is a danger that students do not have time to think in a busy classroom situation. It appears that thinking is more likely to happen outside of the classroom, with peers, in assignment writing, or when thoughts simply come. The challenge to nursing education is that not only may teachers be limiting students thinking opportunities, but they may be directing thinking in a way that maintains the status quo. If nursing is to equip itself as a dynamic profession and take initiative for shaping its own future, then close attention must be paid to enabling thinking.  相似文献   
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BACKGROUND: Patients with localized esophageal carcinoma often develop locoregional and distant disease recurrence. The current study investigated the outcome of a new chemotherapy combination as induction therapy before chemoradiotherapy. METHODS: Forty-three patients with resectable carcinoma of the esophagus or gastroesophageal junction were enrolled. Most of the tumors were endoscopic ultrasonography (EUS) (EUS)T3 (84%) and (EUS)N1 (63%). The patients received < or = 2 6-week cycles of CPT-11 and cisplatin followed by chemoradiotherapy (45 grays with 5-fluorouracil and paclitaxel). Five to six weeks after chemoradiotherapy, the patients underwent staging and surgery. The feasibility, curative resection rates, overall and disease-free survival rates, rate of significant pathologic response, and patterns of disease recurrence were assessed. RESULTS: Of the 43 patients, 39 (91%) underwent an R0 resection. Two patients (5%) died after surgery. A pathologic complete response (pathCR) was observed in 11 (28%) of the 39 patients (or 26% of the 43 patients). In addition, 16 patients (41% of 39 patients or 37% of 43 patients) had < 10% viable tumor in the surgical specimen (pathPR). A comparison of endoscopic ultrasonograpy T and N classifications with surgical T and N classifications demonstrated significant down-staging (P < 0.01). The median survival period of all 43 patients was 22.1 months. Patients who had achieved a pathCR or pathPR had a longer median survival (25.6 months) than those who achieved less than a pathPR (18.5 months; P = 0.52). None of the clinical parameters examined were found to correlate with survival or pathologic response. CONCLUSIONS: CPT-11-based induction chemotherapy resulted in substantial pathCR and pathPR rates, both of which lead to a favorable survival outcome. The three-step strategy needs to be developed further, with the investigation of targeted therapies with chemotherapy and radiotherapy.  相似文献   
59.

Introduction  

Genetic polymorphisms in the promoter region of the tumour necrosis factor (TNF) gene can regulate gene expression and have been associated with inflammatory and malignant conditions. We have investigated two polymorphisms in the promoter of the TNF gene (-308 G>A and -238 G>A) for their role in breast cancer susceptibility and severity by means of an allelic association study.  相似文献   
60.
OBJECTIVE: The metaplastic change of Barrett's oesophagus is linked to both acid and duodenal reflux together with impaired motility. Proton pump inhibitors (PPI) reduce acid reflux, but no treatment is available that reduces duodenogastro-oesophageal reflux (DGOR). The aim of this study was to investigate whether adding a prokinetic to PPI treatment could improve oesophageal motility and subsequently reduce reflux. METHODS: Two groups of patients with Barrett's oesophagus on PPI therapy (prokinetic, n = 12; placebo, n = 11) were investigated. At visit 1, ambulatory oesophageal manometry was performed, and peristaltic and simultaneous wave percentage and characteristics were measured. DGOR and pH measurements were also performed. After treatment with either the prokinetic cisapride or placebo, all investigations were repeated (visit 2). Analysis of covariance and Spearman's correlation coefficients of changes from visit 1 to visit 2 were used to compare data. RESULTS: There was no significant difference between the two groups with respect to DGOR, DGOR characteristics, or the percentage of peristalsis and simultaneous waves and their characteristics. There was no correlation between DGOR and motility changes. Although no significant differences existed between acid reflux in the two groups, five patients with high supine acid reflux showed a significant reduction after treatment with cisapride. CONCLUSIONS: Addition of cisapride to PPI treatment does not appear to improve oesophageal motility or reduce DGOR in patients with Barrett's oesophagus.  相似文献   
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