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961.
We report a unique case of renal echinococcal disease. The patient presented with only a left renal pelvic filling defect without hepatic, pulmonary or other renal involvement. Management consisted of successful exploration and removal of the hydatid mass without sacrifice of renal tissue. The pathogenesis, diagnosis and treatment of echinococcal disease are reviewed.  相似文献   
962.
Objectives : To determine the efficacy of antimicrobial treatment in non-dysenteric persistent diarrhoea in a community setting. Methods : In this double-blind field trial, 156 children aged 4 36 months with persistent diarrhoea not associated with Giardia lamblia infestation seeking treatment in a community outpatient clinic, were randomized to receive a combination of nalidixic acid and metronidazole, metronidazole alone, or placebo for 7 days. Results : In comparison with placebo, metronidazole treatment did not result in a significant reduction in the mean post-enrolment diarrhoeal duration and stool frequency, increase in the proportion of patients recovered by days 3, 5 and 7 of treatment, and increase in weight gain at days 7 and 14. Comparing the combination of nalidixic acid and metronidazole with metronidazole alone, 17.5% more children treated with the combination recovered by day 3 of treatment ( p = 0.08) and the mean stool frequency ascertained on day 7 for the previous 24 h was 26.8% less in them ( p = 0.05). The weight gains at days 7 and 14 were similar in the two groups. Conclusions : These findings indicate that metronidazole offers no therapeutic benefit in persistent diarrhoea not associated with Giardia lamblia and nalidixic acid has only a modest clinical benefit, which is not substantial enough to warrant its routine use.  相似文献   
963.
The objective of the present study was to compare the quantitative differences in the beta 1- vs. beta 2-adrenoceptor affinity and selectivity of cetamolol and its enantiomers to the reference compounds atenolol, betaxolol, and ICI-118,551, using isolated tissues obtained from the dog, guinea pig, and rat. Cetamolol antagonized the beta-adrenoceptor-mediated responses induced by isoproterenol, epinephrine, norepinephrine, and salbutamol, in tissues from both the dog and guinea pig, in a concentration-dependent manner. For a given tissue, the beta-adrenoceptor antagonist activity of cetamolol (measured as a pA2 or pKB value) was independent of the agonist used. In the dog tissues, cetamolol was more potent at inhibiting responses in the coronary artery (beta 1-adrenoceptors) than in the saphenous vein (beta 2-adrenoceptors). In the guinea pig tissues, the potency of cetamolol was approximately the same in the trachea (mixed beta 1- and beta 2-adrenoceptors) and atria (predominately beta 1-adrenoceptors), but lower in the soleus muscle (beta 2-adrenoceptors). Studies with the S-(-) and R-(+) enantiomers of cetamolol demonstrated that the S-(-) enantiomer was approximately 100-fold more potent at beta 1-adrenoceptors than the R-(+) enantiomer. In rat brain, cetamolol displaced [3H]-dihydroalprenolol bound to homogenates of cortex (beta 1-adrenoceptor binding sites) and cerebellum (beta 2-adrenoceptor binding sites). The potency of cetamolol at beta 1-adrenoceptors was found to be similar to that of betaxolol but greater than that of atenolol. However, the magnitude of the beta 1-adrenoceptor selectivity displayed by atenolol and betaxolol was greater than that displayed by cetamolol. In contrast, ICI-118,551 was found to possess potent and selective affinity for beta 2-adrenoceptors.  相似文献   
964.
965.
966.
Summary  Ninety-six consecutive above-knee femoropopliteal bypasses, using polytetrafluoroethylene (PTFE) preferentially, were performed for limb-threatening ischaemia. Cumulative primary graft patency was 68 per cent, 49 per cent and 36 per cent and limb salvage 93 per cent, 85 per cent and 75 per cent at 1, 3 and 5 yr respectively. As a result of poor long term survival (51 per cent at 5 yr), and the healing of remedial lesions before graft occlusion, 68 patients (72 per cent) required no further intervention. Eighteen secondary bypasses were undertaken, 12 using ipsilateral saphenous vein. In this group of elderly patients with poor life expectancy, where a limited operation is desirable, the use of PTFE provided excellent limb salvage with low morbidity. Although we can no longer justify our continued use of PTFE in every case of critical ischaemia because of its inferior patency to autogenous vein, we continue to use it preferentially in patients whose lifespan is likely to be short and in cases where a remedial lesion is present.  相似文献   
967.
Abstract: We describe a 9-year-old boy with an Ro-positive, subacute, cutaneous lupus rash associated with homozygous C2 deficiency. His response to a mild topical steroid and sunscreen was excellent. Hereditary complement deficiency and its association with childhood lupus erythematosus are discussed.  相似文献   
968.
969.
Levels of forebrain serotonin (5-HT), tryptophan, 5-hydroxyindoleacetic acid (5-HIAA) and hydroxylase cofactor (BH4) were comparable in two experimental mouse strains (A/J and C57B1/6J) despite 2–3-fold differences in vitro in the relative activities of forebrain and midbrain tryptophan-5-monooxygenase (TPOH; EC 1.14.16.4). The enzyme activities did not differ with respect toKm for cofactor at saturating levels, but manifested different degrees of cooperativity with respect to cofactor when examined with BH4 concentrations within a physiological range. They differed also in the frequency and amplitude of kinetic variation around comparable mean velocity slopes across cofactor and time; in resistance to pre-incubation inactivation and responsiveness to its facilitation by calcium; in molecular weight heterogeneity as reflected in the distribution of molecular weight forms by gel diffusion chromatography; and in the number of peaks in power spectral analysis of kinetic variation patterns. Although the potential roles of small-molecule ligand and/or regulator proteins have not been ruled out, we hypothesize that differences in conformational stability underlie the differences in regulatory properties and make one enzyme activity more vulnerable to occlusive influences in vivo.  相似文献   
970.
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