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Kent-Man Chu MB BS FRCS Ronnie Poon MB BS FRCS Henry H. Tuen MB BS Simon Y.K. Law MB BCh FRCS Frank J. Branicki DM FRCS FRACS John Wong PhD FRCS FACS 《Gastrointestinal endoscopy》1997,46(6):503-506
Background: A number of noncommercial preparations of urease test have been described. The present prospective study evaluated the accuracy of one such preparation for the diagnosis of Helicobacter pylori infection. Methods: From February 1996 to November 1996, all patients undergoing elective upper endoscopy in a single endoscopy facility were included. Three antral biopsy specimens were taken. Two specimens were subjected to histologic examination, and one specimen was placed into a “locally made rapid urease test” (LRUT). Results of histologic examinations were taken as standards for comparison. The final result of LRUT was obtained on scrutiny of color changes at 4 hours after the start of the test. Results: Two thousand three hundred sixteen patients (male/female = 1.5:1) with a mean age of 56.7 ± 0.4 years were included. Five hundred sixty-two patients (24.3%) had a history of eradication treatment for H. pylori. Nine hundred fifty-three patients (41.1%) were found to be positive for H. pylori on histologic examination. In patients in whom a history of eradication therapy was absent, the sensitivity, specificity, and positive and negative predictive values of the LRUT were 92.8%, 97.6%, 97.5%, and 93.0%, respectively. In patients with a history of eradication treatment, the corresponding figures were 76.1%, 99.6%, 96.2%, and 96.9%. Conclusions: The locally made rapid urease test provides a simple, safe, rapid, inexpensive, and accurate test for the diagnosis of H. pylori infection. (Gastrointest Endosc 1997;46:503-6.) 相似文献
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BACKGROUND & AIMS: The functional significance of intestinal hyperplasia stimulated by insulin-like growth factor (IGF)-I is unclear and has not been studied in a model of mucosal atrophy induced by total parenteral nutrition (TPN). The aim of this study was to determine how IGF-I affects intestinal structure and epithelial function in the absence of luminal nutrition caused by TPN. METHODS: Rats were maintained with TPN with or without IGF-I (800 micrograms/day), and jejunal histology and epithelial ion transport were measured after 5 days. In a third TPN group without IGF-I, a short-term dose of IGF-I was added during in vitro flux chamber experiments. RESULTS: Rats given TPN with IGF-I had greater jejunal mucosal weight, greater protein and DNA content, and increased villus height and crypt depth compared with rats given TPN only. TPN increased ionic permeability and ion transport responses to secretory and absorptive agents. IGF-I in vivo reversed most of these changes; IGF-I in vitro enhanced sodium-dependent glucose absorption but had no other effects. CONCLUSIONS: Coinfusion of recombinant human IGF-I with TPN solution stimulates intestinal hyperplasia and attenuates transport changes induced by TPN. The latter effect seems to be primarily associated with the growth state of the epithelium. (Gastroenterology 1996 Dec;111(6):1501-8) 相似文献
54.
John L. Reid DM Robert J. MacFadyen MD PhD Iain B. Squire MB Kennedy R. Lees MD 《The American journal of cardiology》1993,71(17):E57-E60
Angiotensin-converting enzyme (ACE) inhibitors improve survival in heart failure and delay progression to clinical heart failure in patients with left ventricular dysfunction after myocardial infarction. Increasing numbers of older patients are being considered for such treatment. However, there are reports of excessive and prolonged decreases in blood pressure (BP) after the first dose of some ACE inhibitors. We have studied the hemodynamics, pharmacokinetics, and neurohumoral responses to the first dose of oral captopril 6.25 mg, enalapril 2.5 mg, perindopril 2.0 mg, intravenous enalaprilat 1.5 mg, and perindoprilat 1.0 mg, compared with oral or intravenous placebo in 6 parallel groups of 12 elderly patients each with moderate-to-severe (New York Heart Association classes II-IV) heart failure. Oral dosing with active drugs led to different temporal responses. After captopril, there was an early short-lived decrease in BP. Enalapril led to a later long-lasting decrease, but perindopril was not different from placebo. Intravenous enalaprilat and intravenous perindoprilat each lowered BP to a similar extent. The doses of drugs used appeared to be comparable because plasma ACE inhibition was similar following perindopril or enalapril and also comparing perindoprilat and enalaprilat. These studies indicate that oral ACE inhibitors have different profiles of acute BP changes after the first dose. The explanation is not clear, but could include physicochemical differences in the interaction between prodrug ester and diacid metabolites leading to differences in tissue distribution and local enzyme inhibition. 相似文献
55.
Erectile Impotence in Chronic Alcoholics 总被引:1,自引:0,他引:1
Edward T. H. Tan BSc PhD Ralph H. Johnson DM DSc FRCP David G. Lambie BSc PhD Mithra E. Vijayasenan MB BS FRANZCP Edwin A. Whiteside MB ChB 《Alcoholism, clinical and experimental research》1984,8(3):297-301
Erectile impotence is a common complaint in alcoholics, but its mechanism is unknown. We have studied nocturnal penile erection in 13 alcoholics who complained of impotence. Seven had normal erections and their impotence was therefore psychogenic. Six were found to have diminished or absent nocturnal erections. Plasma concentrations of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were elevated in this latter group, with the exception of one patient who had only raised FSH. They also had more evidence of neurological damage than the other seven alcoholics, and two had evidence of damage to the parasympathetic nervous system. Investigation of erection during sleep in alcoholic patients with impotence may be useful in differentiating clinically between patients with psychogenic causes and patients with organic causes of impotence. 相似文献
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Saurabh Kumar Gupta MD DM Anita Saxena MD DM Rajnish Juneja MD DM Gurpreet Singh Gulati MD 《Congenital heart disease》2014,9(4):E125-E128
Atresia of the left main coronary artery is a rare anomaly that, if left untreated, has an unfavorable outcome. We hereby report left main coronary artery atresia in a child with tetralogy of Fallot with absent pulmonary valve and discuss the possible developmental basis of the association. 相似文献
60.