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This study compared high dose ranitidine versus low dose omeprazole with antibiotics for the eradication of H pylori. 80 patients (mean age 48 years, range 18-75) who had H pylori infection were randomised in an investigator-blind manner to either a two-week regime of omeprazole 20 mg daily, amoxycillin 500 mg tid and metronidazole 400 mg tid (OAM), or ranitidine 600 mg bd, amoxycillin 500 mg tid and metronidazole 400 mg tid (RAM), or omeprazole 20 mg daily and clarithromycin 500 mg tid (OC), or omeprazole 20 mg daily and placebo (OP). H pylori was eradicated in 6 of 19 patients in the OAM group (32%); 8 of 18 in the RAM group (44%), 4 of 15 in the OC group (27%); none of 18 in the OP group (0%). [< P0.005 for OAM, RAM, OC vs OP; P = N.S. between OAM, RAM, OC]. Overall metronidazole resistance was unexpectedly high at 58%. Eradication rates in metronidazole sensitive patients were 71% (5/7) and 100% (3/3) for OAM and RAM respectively. In conclusion, H pylori eradication rates using high dose ranitidine plus amoxycillin and metronidazole may be similar to that of low dose omeprazole in combination with the same antibiotics for omeprazole with clarithromycin. Overall eradication rates were low due to a high incidence of metronidazole resistance but were higher in metronidazole-sensitive patients. Even high dose ranitidine with two antibiotics achieves a relatively low eradication rate. These metronidazole-based regimens cannot be recommended in areas with a high incidence of metronidazole resistance.  相似文献   
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Lung denervation in ducks, by sectioning all vagal branches to one lung following mid-cervical vagotomy on the other side, resulted in immediate bradycardia and fall in breathing frequency. Some 3-5 weeks after lung denervation breathing frequency was within the normal range but the lung inflation reflex, present in unilaterally vagotomized sham-operated ducks, was abolished. During 2 min dives there were no significant differences between sham-operated and denervated ducks in heart rate, arterial blood pressure, blood gas tensions and pH(a). However, during recovery from diving heart rate increased more slowly in denervates and breathing rate was significantly below that attained by shams, although tidal volume rose to a maximum increase of 139% to a maximum of 225% of the pre-dive value in denervates in contrast to a maximum increase of 139% of pre-dive in sham-operated ducks. Both sham-operated and denervated ducks exhibited a significant fall in diastolic blood pressure 60 sec after emergence...  相似文献   
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In a consecutive series of 515 first-ever strokes in a community-based study of stroke that combined prompt clinical assessment by a study neurologist with a high rate of confirmed pathologic diagnosis, 108 cases (21%) had a lacunar syndrome. A computed tomography (CT) scan was performed in 104 (96%) of these cases. Only 3 cases had primary intracerebral hemorrhage, and another 3 had "inappropriate" areas of infarcts were seen in 34 of the remaining 98 (35%) CT scans. The crude annual incidence of lacunar infarction was 0.33/1,000. There was no excess risk among men. The case fatality rates were 1% at 1 month and 9.8% at 1 year. The rate of recurrent strokes was 11.8% in the first year. Among patients surviving 1 year, 66% were capable of independent existence.  相似文献   
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Breast cancer detection: one versus two views   总被引:2,自引:0,他引:2  
Mammographic examinations of 169 patients with 172 biopsy-proved carcinomas, and of 194 healthy subjects, were interpreted independently and retrospectively by three experienced mammographers, initially as single-view oblique examinations and 6 months later as two-view oblique-cephalocaudal examinations. For the single-view examinations of the cancer patients, 67% of the cancers were correctly recommended for biopsy, additional views were requested for 23%, and a "negative" interpretation was made for 10%. For the single-view examinations of healthy subjects, biopsy was recommended for 7% and additional views were recommended for 32%. For the two-view examinations of women with cancer, 80% of the cancers were correctly recommended for biopsy, additional views were requested for 4%, and a "negative" interpretation was made for 16%. For two-view examinations of healthy subjects, biopsy was recommended for 7% and additional views were requested for only 5%. The authors conclude that single-view screening should not be performed, because it would lead to an excessive number of "call-back" examinations of healthy patients, producing additional cost and anxiety that would outweigh any theoretical benefit.  相似文献   
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BACKGROUND AND PURPOSE: The role of polymorphisms of the platelet glycoprotein (GP) IIb/IIIa receptor in the development of cardiovascular disease has been the subject of intensive research. The aim of this study was to determine the association of the HPA-3 polymorphism of platelet GPIIb with ischemic stroke and subsequent survival and to identify possible interactions of HPA-3 with classic risk factors. METHODS: HPA-3 genotype was determined by restriction fragment length polymorphism in 515 patients with ischemic stroke and 423 healthy, age-matched control subjects. RESULTS: There was no significant difference in the genotype distribution of patients and controls, nor was there any difference when patients were subclassified into small- and large-vessel disease. The genotype distribution of the 231 patients subsequently dying during 2.8 years of follow-up (aa=45.0%, ab=46.8%, bb=8.2%) was significantly different from that of those still alive (aa=37.0%, ab=48.2%, bb=14. 8%) (P=0.03). In a Cox regression model, the relative risks for poststroke mortality in patients of aa and ab genotype compared with those of bb genotype were 2.42 (95% CI, 1.24 to 4.71) and 2.13 (95% CI, 1.09 to 4.17), respectively, after we accounted for confounding factors. In addition, significant interactions of HPA-3 with the Pl(A) polymorphism of GPIIIa (P=0.002) and with fibrinogen (P=0.01) were identified in relation to mortality. CONCLUSIONS: HPA-3 is related to poststroke mortality, and the significant interaction of HPA-3 with Pl(A) and fibrinogen suggests that it may in some way influence the interaction of GPIIb/IIIa with fibrinogen, particularly in the presence of high fibrinogen.  相似文献   
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