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31.
As a part of our ongoing study on Alzheimer's disease (AD) in elderly African Americans, we obtained clinical assessment and apolipoprotein E (ApoE) genotype data on 288 individuals (including 60 with AD). The ApoE σ4 allele frequency was significantly increased in AD patients compared with controls. The age-adjusted odds ratio (OR) for AD in σ4 homozygotes was 4.83 (95% confidence interval [CI], 1.71–13.64) compared with the σ3/σ3 genotype, but the OR for AD with the σ3/σ4 genotype did not reach significance (1.20; 95% CI, 0.58–2.45). These findings suggest that the association between ApoE σ4 and AD is weaker in African Americans than in whites.  相似文献   
32.
Aplastic anaemia is both frequent and difficult to manage in patients with dyskeratosis congenita (DC). We recently treated a 23-year-old male for a year with granulocyte colony-stimulating factor (G-CSF) and erythropoietin (Ep), with an excellent neutrophil response, and a transient effect on haemoglobin levels. G-CSF alone or combined with other cytokines may provide at least a partial effect in pancytopenic patients with DC.  相似文献   
33.
Urinary tract injuries during obstetric intervention   总被引:11,自引:0,他引:11  
A retrospective case record review of obstetric urinary tract injury in the Grampian region from 1976 to 1993 identified 16 cases of bladder injury (0.1 per 1000 deliveries, 1.4 per 1000 caesarean sections and four cases of ureteric injury (0.03 per 1000 deliveries, 0.27 per 1000 caesarean sections). Diagnosis of bladder injury was immediate, but of ureteric injury often delayed. Although the injury rates are lower than previously reported and previously reported risk factors not confirmed, this audit has resulted in guidelines for junior staff, compliance with which will be monitored, and every case of urinary tract injury will be reviewed.  相似文献   
34.
Pseudomonas aeruginosa 455, isolated in Ankara, Turkey, produced a pI 6.2 beta-lactamase determined by plasmid pMLH53 and resisted all beta-lactams except carbapenems. This beta-lactamase, named OXA-14, corresponded to OXA-10 (PSE-2) except that aspartate replaced glycine at position 157 and thus is intermediate between OXA-10 and OXA-11, which has aspartate at position 157 and a further substitution at position 143.  相似文献   
35.
The influence of metabolic control (HbA1c), noradrenaline (NA) and insulin-like growth factors (IGF-I and IGF-II) on renal function and size was investigated in 11 insulin-dependent diabetes mellitus patients aged 11–17 years. Renal function was evaluated in terms of glomerular filtration rate (GFR) and effective renal plasma flow (ERPF). Renal size was determined as renal parenchymal volume (RPV) by ultrasonography. The patients' HbA1c values ranged from 8.2% to 12.9% (normal range 5.5–8.5%) and their GFR and ERPF were higher than normal. Their IGF-II values were higher, and NA and IGF-I levels were lower than those of healthy controls. Inverse correlations between NA and GFR (r=–0.66) and NA and ERPF (r=–0.63) were found. No correlation was found between serum IGF-I and renal functional parameters. The IGF-II values correlated with GFR and HbA1c (r=0.63,r=0.70 respectively). There were linear correlations between RPV and GFR, RPV and ERPF, HbA1c and GFR, and ERPF and RPV. Decreased NA concentrations and increased IGF-II values appear to be factors contributing to renal hyperfunction in these patients.  相似文献   
36.
A case study of multicentric reticulohistiocytosis is presented with extensive immunohistochemical studies of the infiltrate in both paraffin and cryostat sections. These studies showed that the cells are of monocyte/macrophage origin. B- and T-cell gene rearrangement analysis of multicentric reticulohistiocytosis was also performed and showed a germline configuration.  相似文献   
37.
The pharmacokinetics and pharmacodynamics of the anticholinergic and calcium antagonistic drug terodiline, N-tert-butyl-1-methyl-3,3-diphenylpropylamine, have been studied in beagle dogs. The bioavailability was about 25% (0.15 and 0.5 mg/kg), the terminal half-life 3 hr, the systemic clearance 40 ml/min..kg, the volume of distribution (V beta) about 7 l/kg and the unbound fraction in serum 0.14. p-Hydroxyterodiline and p-hydroxy-m-methoxyterodiline were quantitated and constituted 15-40% and 25%, respectively, of the amount excreted in urine (about 60% of the dose) and were the main metabolites, as in man. The dog was used as an experimental model to study the chronotropic effect. An increased heart rate was observed after acute administration of high doses of terodiline as well as after p-hydroxyterodiline. A 20% increase in heart rate was observed at a mean serum concentration of 1086 and 1010 micrograms/l following intravenous injection of terodiline or p-hydroxyterodiline, respectively. The corresponding unbound concentrations were 150 and 474 micrograms/l. The potency ratios of terodiline/p-hydroxyterodiline was 0.9 +/- 0.2 (based on total concentrations) and 3.2 +/- 0.8 (based on unbound concentrations). The estimated potency of parent drug and main metabolite and the fact that p-hydroxyterodiline constitutes 10-20% of the terodiline steady-state level in man, indicate that the contribution of the metabolite to the chronotropic effect observed in clinical studies is minor.  相似文献   
38.
Total global biodiversity is estimated at between 3 and 500 × 106 species of prokaryote and eukaryote organisms spread across 70 or more phyla. The marine macrofauna alone are estimated between 0.5 and 30 × 106 species and represents a broader range of taxonomic diversity than that found in the terrestrial environment, which has been the traditional source of natural products. With a typical eukaryote possessing 50,000 genes, the global marine macrofauna are the source of 2.5 × 1010 to 1.5 × 1012 primary products and an associated extensive range of secondary products. However, only a few thousand novel compounds from marine organisms have been described. These compounds have proven unique in chemical and pharmacological terms but, as yet, no therapeutic agents have resulted. Given a broader drug discovery strategy, and facilitated by technological advances, it is predicted that the characterisation of marine chemical diversity will be accelerated. Strategies for drug discovery from the virtually untapped chemical diversity of marine organisms are discussed. © 1994 Wiley-Less, Inc.  相似文献   
39.
Public awareness of prostate cancer is increasing. Growing numbers of middle-aged men are seeking screening tests for prostate cancer and advice about its surgical treatment. Contrary to the hopes of many, the benefit of early diagnosis and by radical prostatectomy remains in doubt. Recent analyses suggest that ''watchful waiting'', with no immediate treatment, may be an equally effective option. If this is true, why screen? Why operate? These questions should be a cause of concern to more than 1 million British men who are unaware that they have prostate cancer and to the providers of health care who have failed to address this dilemma. A national audit and randomised clinical trial are indicated.  相似文献   
40.
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