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Respiratory viruses in children admitted to hospital in Edinburgh 1972-1985   总被引:1,自引:0,他引:1  
The temporal incidence of respiratory viruses identified in children admitted to an Edinburgh hospital over a period of 14 years, 1972-1985, is described, Respiratory syncytial (RS) virus was identified most often, usually (but not in 1979 and 1985) with single peaks of activity in the winter months. Influenza virus infections were seen in the winter and spring but we failed to find evidence of interference between RS and influenza virus. Of the viruses studied, the parainfluenza viruses were the least predictable in their epidemiological behaviour. The results of this study are compared with those of others and the role of certain aspects of the weather is considered.  相似文献   
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Summary The prevalence of ESBL was determined among isolates of Escherichia coli (n = 571) and Klebsiella spp. (n = 196) collected during a 1-week study period in 8 university and 3 large regional laboratories all over the Netherlands. 18 isolates were positive for at least one of the screening tests used, i.e., VITEK-ESBL, E-test ESBL and MIC ratio of ceftazidime/ceftazidime-clavulanic acid, cefotaxime/cefotaxime-clavulanic acid. In 5 of these 18 putative ESBLs no betalactamase production was detectable. A TEM type was found in three E. coli and two Klebsiella spp. An SHV type was present in five Klebsiella spp. In one E. coli and one Klebsiella pneumoniae both enzymes were present. In one Klebsiella oxytoca neither of the two enzymes was present. Using PCR for both ESBL TEM and ESBL SHV, an SHV ESBL was found in one E. coli and four Klebsiella isolates. The mutations at position 238 and 240 were already described. In one E. coli isolate a TEM ESBL was found with three mutations, at position 21, 164 and 265. These mutations were already described in other ESBLs but not in this combination suggesting a new TEM ESBL. The overall prevalence of ESBL producing E. coli and Klebsiella spp. was less than 1% (6 out of 767). Received: December 14, 1998 · Accepted: September 19, 1999  相似文献   
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Declining testicular function with age. Hormonal and clinical correlates   总被引:6,自引:0,他引:6  
Testicular endocrine function and androgen-dependent secondary sexual characteristics were assessed in 283 men 18 to 96 years of age. Mean serum total testosterone levels remained unchanged up to age 70 and declined thereafter. In 29 per cent of the men over 70 years of age total testosterone levels were below the lower limit of normal for young adults, In contrast, mean free or unbound testosterone levels declined after age 50 and were below the lower limit of normal for young adults in 40 per cent of the men over 70 years of age. Serum-luteinizing hormone and follicle-stimulating hormone levels showed a slight but steady rise after age 40 which became more abrupt after age 70. Serum gonadotropin levels were elevated in approximately 60 per cent of the men over 70 years of age.Mean testis length and volume were decreased in 78 per cent and 37 per cent, respectively, of the men over 60 years of age. Facial, pubic and axillary hair were also reduced in amount whereas the prostate was enlarged in 73 per cent of the elderly men. There appeared to be an inverse relationship in older men between testicular size and gonadotropin levels, and a direct relationship between testicular and prostatic sizes.It would appear that some degree of Leydig cell hypofunction commonly begins at around 45 to 50 years of age, becoming more pronounced after age 70. The concomitant elevation in serum gonadotropin levels at this time indicates that this is due to a primary decline in testicular function and is not secondary to pituitary hypofunction.  相似文献   
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Eubacterium lentum and phenotypically similar organisms synthesize a steroid 21-dehydroxylase which converts biliary tetrahydrodeoxycorticosterone to pregnanolone. Tetrahydrodeoxycorticosterone, in contrast to pregnanolone, is carcinogenic for hamster embryonic cells (HECT test). In patients with recently diagnosed, untreated sigmoidal or rectal cancer the fecal concentration of 21-dehydroxylating organisms is reduced by more than 99% as compared with age-matched controls. The lack of fecal 21-dehydroxylating organisms, therefore, is a potential marker for the disorder. The role of steroid 21-dehydroxylase in the pathogenesis of colorectal cancer is unknown.  相似文献   
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Fanconi anemia (FA) is a genetic disease characterized by bone marrow failure and cancer predisposition. Here we have identified Spanish Gypsies as the ethnic group with the world's highest prevalence of FA (carrier frequency of 1/64-1/70). DNA sequencing of the FANCA gene in 8 unrelated Spanish Gypsy FA families after retroviral subtyping revealed a homozygous FANCA mutation (295C>T) leading to FANCA truncation and FA pathway disruption. This mutation appeared specific for Spanish Gypsies as it is not found in other Gypsy patients with FA from Hungary, Germany, Slovakia, and Ireland. Haplotype analysis showed that Spanish Gypsy patients all share the same haplotype. Our data thus suggest that the high incidence of FA among Spanish Gypsies is due to an ancestral founder mutation in FANCA that originated in Spain less than 600 years ago. The high carrier frequency makes the Spanish Gypsies a population model to study FA heterozygote mutations in cancer.  相似文献   
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