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用放射配体受体结合试验法,研究了新化合物三环哌酯与人大脑皮质M受体的结合特性,并与QNB作了比较。饱和实验结果显示,[3H]三环哌酯的结合参数与[3H]QNB相近,两种配体的作用均符合单位点模型。竞争性抑制实验结果表明二者作用强度相当。[3H]三环哌酯的结合和解离速率常数均较[3H]QNB大,且其与皮质M受体的解离受季铵酚的变构调节,结果提示,两种配体与M受体有一些不同的结合特性,在M受体研究中,[3H]三环哌酯可以作为[3H]QNB的补充工具。  相似文献   
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BACKGROUND: The pattern of growth of the uterus was examined by ultrasound examinations of 358 girls who attended a paediatric endocrine outpatient department but were shown not to have any endocrine defect. METHOD: The uterus was measured in length and width at the cervix and at the fundus (cm). Endometrial thickness was measured (mm). Scans were divided by Tanner breast stage and the dimensions compared by one way analysis of variance (ANOVA, with the Student Newman Keuls post hoc test). RESULTS: There was an increase in uterine length, diameter of the fundus, and endometrial thickness at each breast stage from 1 to 5 (ANOVA, p < 0.05), and in the diameter of the cervix with each breast stage from 1 to 4 (ANOVA, p < 0.05). The ratio of the fundus to the cervix increased from 0.95 to 1.29 between breast stages 1 and 4. CONCLUSION: The onset of puberty is marked by an increase in the dimensions of the uterus and in endometrial thickness, but also by a change in the shape of the uterus from a tubular to a pear shaped organ.  相似文献   
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Since indium-111 white blood cell (In-111 WBC) scintigraphy is often used to evaluate for osteomyelitis in bone fractures, it is important to know if noninfected fractures have In-111 WBC uptake. Twenty-seven noninfected closed fracture sites in 19 patients were prospectively evaluated with technetium-99m methylene diphosphonate bone scintigraphy and In-111 WBC scintigraphy. In-111 WBC uptake was present in 41% of the 27 sites. In the 11 positive sites, the In-111 WBC uptake was 1+ (definite but minimal) in 55%, 2+ (moderate) in 36%, and 3+ (marked) in 9%. The visual intensity of the radioactive uptake on In-111 WBC scintigrams relative to that on bone scintigrams was less in 82%, equal in 9%, and greater in 9%. The visual size of the area of uptake on In-111 WBC scintigrams and bone scintigrams was smaller in 36%, equal in 55%, and greater in 9%. Factors that may help distinction of In-111 WBC uptake due to fracture alone from infection associated with fracture are discussed.  相似文献   
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One hundred forty-eight patients with gastrointestinal disease, 50 patients with the irritable bowel syndrome (IBS) and 49 each with peptic ulcer and inflammatory bowel disease, were interviewed to determine if they had proctalgia fugax (PF) and if the symptom was associated with the IBS. One-third of the patients had PF. It occurred in 51% of females and 12% of males (p less than 0.001). When corrected for sex, PF was no more prevalent in IBS than in peptic ulcer or inflammatory bowel disease. Only two of six previously described IBS symptoms were more prevalent in the PF patients. Attacks occurred in the day in 94%, and one-third of sufferers related them to defecation. The pain was localized in the anus in 90%, occurred less than five times a year in 51%, and lasted less than 1 min in 57%. In most, activity was not interrupted by this pain and only 20% had ever reported it to a physician. PF is very common among patients with abdominal symptoms, but is not related to the IBS. Since it is infrequent, benign, and transient, PF is usually not mentioned to the physician.  相似文献   
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Introduction  

Intensive care unit (ICU) patients often suffer from subcutaneous oedema, due to administration of large fluid volumes and the underlying pathophysiological condition. It is unknown whether the presence of subcutaneous oedema impairs the absorption of dalteparin, a low molecular weight heparin, when it is given by subcutaneous administration for venous thromboembolism prophylaxis. The objective of this study is to compare the anti-Xa activity of dalteparin after subcutaneous administration in ICU patients with and without subcutaneous oedema.  相似文献   
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