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501.
BACKGROUND: The combination of omeprazole with amoxycillin or clarithromycin is used as treatment against Helicobacter pylori. It seems likely that the antibacterial activity of the antibiotic may be improved by increasing gastric pH towards neutrality, and a twice daily regimen of omeprazole is probably needed. AIM: To assess the effects of twice daily administration of omeprazole 20 and 40 mg. METHODS: Twelve duodenal ulcer patients in remission were randomized to receive in single-blind fashion either placebo, omeprazole 20 mg or omeprazole 40 mg twice daily (08.00 and 20.00 h). On the sixth day of dosing they underwent 24-h gastric pH-metry. RESULTS: Omeprazole 20 and 40 mg b.d. produced marked decreases (P < 0.001) of 24-h gastric acidity (pH 5.4 +/- 0.9 and pH 5.7 +/- 0.6, respectively, vs. a basal pH of 1.4 +/- 0.2) and kept gastric pH at levels higher than 3.0 for almost 24 h. Gastric pH was kept above 5.0 for about 18 h and above 6.0 for about 10 h, while the time spent above 7.0 did not exceed 3 h. There were no significant differences between the two omeprazole dosages at any pH threshold. CONCLUSION: Omeprazole 20 mg b.d. is sufficient to render the gastric milieu as anacidic as possible in duodenal patients.  相似文献   
502.
Normal quantitative circumferential profile limits were established for a 30 degrees bilateral rotating slant-hole (RSH) collimator tomographic system. This system's value in detecting segmental coronary artery disease was assessed in a study evaluating 196 patients by thallium 201 myocardial scintigraphy and coronary arteriography. Profile curves were calculated from images of 20 healthy patients and used to identify significant coronary artery disease (greater than or equal to 70% diameter narrowing) in the left anterior descending (LAD), the right, and the left circumflex (LCx) coronary arteries. In a group of 86 patients, an abnormality on the apical or middle plane optimally identified segmental coronary artery disease. When such abnormalities were prospectively evaluated in a test group of 110 patients, the sensitivity and specificity were 79% and 93% for LAD, 90% and 90% for right, and 83% and 83% for LCx coronary artery disease. Compared with qualitative interpretation of the planar and tomographic images, quantitative tomography significantly improved the sensitivity of T1-201 imaging in detecting LAD, right, and LCx coronary artery disease (P less than .001) in patients with or without previous myocardial infarction.  相似文献   
503.
孙颖  王德心  鲁桂琛 《药学学报》1996,31(3):186-190
在乙肝病毒表面抗原结构研究的基础上,自行设计了三个新型结构的肽疫苗,采用Boc化学和Fmoc化学相匹配的策略,应用固相肽逐步合成法合成,产物经氨基酸分析鉴定。  相似文献   
504.
Wood  GS; Warnke  RA 《Blood》1982,59(5):913-922
Techniques were developed for the preparation of frozen sections from undecalcified bone marrow biopsy cores and bone marrow aspirates. Selected indirect antibody and biotin-avidin detection systems, employing immunoperoxidase or immunofluorescent labels, were studied to determine which were best suited for bone marrow frozen section immunohistopathology. Methods employing murine hybridoma monoclonal antibodies illustrate the immunophenotyping of representative lymphoid neoplasms, involving bone marrow. The results of immunohistologic staining were comparable to those of fluorescence-activated cell sorter (FACS) analysis of cell suspensions. The advantages and limitations of immunohistologic techniques are discussed as they relate to immunophenotypic studies previously feasible only with bone marrow cell suspensions. Frozen section immunohistologic techniques serve as useful adjuncts to the conventional evaluation of bone marrow aspirates and biopsies.  相似文献   
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Iliac arteriovenous fistulas are an uncommon condition, which may be spontaneous or traumatic in nature. Such fistulas classically present with a triad of high‐output cardiac failure, pulsatile abdominal mass with a bruit and unilateral leg ischaemia or venous congestion. We describe a case of an iliocaval fistula secondary to rupture of a common iliac artery aneurysm, with an unusual presentation of multiple organ failure, masquerading as sepsis. We describe the CT findings of iliocaval fistula, which was the means of diagnosis in this study.  相似文献   
510.
以豚鼠离体回肠和结肠带为标本,观察蛇床子素(Ost)的作用与Ca~(2+)的关系。结果表明:Ost和钙拮抗剂Ver产生剂量依赖性抑制乙酰胆碱(ACh)、组胺及KCl所致回肠条或结肠带的收缩;非竞争性拮抗CaCl_2累积量—效曲线,pD_2分别为4.41±0.15,7.0±0.2。Ost 100μmol/L和Ver 1μmol/L均能对抗小剂量Ca~(2+)所致结肠带收缩,但被加入较大量Ca~(2+)所取消。Ost和Ver均能抑制ACh诱导的依内钙性收缩,不影响依外钙性收缩。结果提示Ost具有钙拮抗作用,其作用方式与Ver类似。  相似文献   
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