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A wide range of vascular disorders can affect the spleen. Although clinical presentation is often nonspecific, early diagnosis and treatment are mandatory in most conditions. Noninvasive imaging techniques are well suited to meet these objectives. Familiarity with normal macroscopic and microscopic vascular anatomy is a prerequisite to understand the pathophysiology of vascular disorders of the spleen. This article deals with diseases of the splenic vasculature (aneurysms, arteriovenous fistula, splenic vein thrombosis, collateral circulation in portal hypertension) as well as vascular disorders affecting the splenic parenchyma (splenic infarct, Gamna-Gandy bodies). Primary vascular tumors and tumor-like conditions of the spleen will be discussed very briefly.  相似文献   
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Preparations of the circular muscle layer from the sigmoid colon resected from patients with idiopathic chronic constipation were compared, at an electrophysiological level using the sucrose-gap technique, with preparations of the same region of the intestine resected from patients with rectal carcinoma. Non-adrenergic, non-cholinergic inhibitory neuromuscular transmission, represented by inhibitory junction potentials, was present in preparations from both groups. However, the inhibitory response in preparations from constipated patients had a slower or longer time-course than in those from cancer patients. Also, rebound activity following inhibitory transmission was observed in 34% of preparations from constipated patients but was observed in 67% of preparations from cancer patients. Preparations from both groups displayed the same patterns of spontaneous activity and the same proportion of each group was quiescent. The threshold for generation of action potentials and the passive resistance of the smooth muscle membrane were the same in both groups. However, quiescent preparations from constipated patients were less likely to discharge trains of action potentials when the smooth muscle membrane was depolarized than were preparations from cancer patients. These changes in transmission processes and excitability in tissue from constipated patients are discussed in relation to altered states of colonic motility found in people with idiopathic chronic constipation.  相似文献   
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This study retrospectively compares patients who underwent outpatient transvaginal follicle aspiration with either a propofol- or methohexital-based intravenous sedation technique. Data collected from patient charts (n = 212) over a 46-month period were analyzed to determine the effects of each sedation technique on procedure and recovery times, number of retrieved ova, as well as rates of nausea, fertilization, cleavage, pregnancy, and delivery. All patients were included in the study, regardless of age or diagnosis. procedure time was lower in the propofol group (51 t 18 min) than in the methohexital group (61 I 20 min) (p > 0.01). Patients in the methohexital group (139 2 51 min) spent more time in the recovery room than did those in the propofol group (71 ? 34 min) (p > 0.01). The nausea rates were significantly lower in the propofol group compared with the methohexital group (1.9% vs. 14.4%, respectively) (p > 0.02). Fertilization rate in the propofol group was 77.7% and was 62.9% in the methohexital group (p > 0.01). The numbers of retrieved ova and the cleavage rates were similar in both groups. The rate of pregnancy in patients sedated with propofol (46.1%) was higher than the methohexital group (26.9%) (p > 0.02). Delivery rate was 38.5% in the propofol group and 20.6% in the methohexital group (p > 0.02). In summary, propofol intravenous sedation for transvaginal follicle aspiration was associ- ated with an improved outcome. Pregnancy and delivery rates were higher while nausea, an unpleasant side effect, was sharply reduced.  相似文献   
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Use of Internet information by women with breast cancer   总被引:1,自引:0,他引:1  
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The ethical use of fetal tissue for transplantation and research   总被引:1,自引:0,他引:1  
The exercise of organ and tissue transplantation is a common occurrence in our society Expectations of future advances in this arena are raising many ethical, moral and public-policy questions The scientific data base supporting the usefulness of fetal tissue to repair or reverse disease is modest, and uses are speculative Should fetal tissue transplantation research proceed and, if so, under what conditions? This paper examines the issues related to the use and procurement of fetal tissue for research and transplantation  相似文献   
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