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41.
A study of DNA content by flow cytometry revealed a significant difference between rhabdomyosarcomas, which were mainly non-diploid, and other sarcomas of children which were mainly diploid (p = 0.01). There was no association between DNA ploidy and survival or aggressive behaviour of the tumour as indicated for example by advanced clinical stage or unfavourable histology. While DNA ploidy correlated with age, it did not correlate with any other clinical characteristic. The apparent lack of prognostic value of DNA content may have been masked by some high CV values and overridden by the effect of chemotherapy which was the most significant variable in determining a patient's survival (p = 0.00005).  相似文献   
42.
A total of 675 strains of Salmonella bareilly received from different parts of India and France during 1959-92 were phage typed using six bacteriophages. Overall typability achieved was 90.8% with 23 distinct phage types excluding a group of untypable strains. Phage types have been defined in octal code. Simpson''s coefficient was applied for diversity index having a value of 0.839. This system was found to be reproducible, stable and epidemiologically useful.  相似文献   
43.
Behavioural studies were conducted on a random sample of 38 glass bangle workers engaged in various occupations and exposed to high ambient temperature (38.2 +/- 3.4 degrees C) and radiant heat (46.2 +/- 5.1 degrees C) during their work in the glass bangle industries at Firozabad, India. Twenty-two control subjects of similar age and socio-economic status unexposed to heat during their work were also studied for comparison. The digit span test, digit symbol test, Bourdon-Wiersma vigilance test, flicker fusion test and Maudsley personality inventory (MPI) were used to assess the behavioural changes induced by the existing heat stress. The mean scores of immediate memory were much lower in the exposed population than in the controls thereby indicating impairment of immediate memory in the study group. The visuo-motor coordination and vigilance were also significantly affected. Visual perception showed a downward trend among the glass bangle workers, although the MPI test indicated no personality changes.  相似文献   
44.
Gastrointestinal manifestations of dengue fever are mainly in the form of bleeding or liver function abnormalities. Dengue fever presenting as acute colitis-like picture is not reported to date. We report a 50-year-old man with dengue fever presenting with lower gastrointestinal bleeding and colonoscopic features of acute inflammatory colitis.  相似文献   
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It is clear that the vitamin D endocrine system plays a central role in the maintenance of calcium and phosphate homeostasis. It may be involved in the cellular differentiation and growth of various cells. Investigation of these properties in the future is likely to yield interesting information concerning the biology of this sterol hormone.  相似文献   
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A high incidence of increased plasma level of high density lipoprotein cholesterol (HDL-C) has been reported in cases of lepromatous leprosy. HDL-C levels were estimated in 96 (50 under treatment and 46 untreated) lepromatous leprosy patients and 84 randomly selected matched control patients suffering from other skin diseases attending skin out-patients department. HDL-C estimations were performed for the diagnosis of lepromatous leprosy in patients aged below 60 years, taking plasma HDL-C levels as 28-71 mg./dl. in men and 34-91 mg./dl. in women, as range of normal values. The study revealed that HDL-C levels in lepromatous leprosy group were raised and significantly different when compared with control group (t = 35.1668 and P less than 0.001). The sensitivity of the test was very high, 97.9 per cent (94/96), but specificity was low 80.95 per cent (68/84). False positive and false negative results were 19.04 per cent (16/84) and 2.08 per cent (2/96) respectively. It is opined that a negative test will be mainly useful in excluding diagnosis of lepromatous leprosy.  相似文献   
50.
Endothelin receptors (ETRs) display subtype heterogeneity and are widely distributed throughout the tissues of the periphery and central nervous system. In order to gain further insight into the potential molecular differences of ETRs, we initiated molecular cloning of ETR genes by screening for the appearance of 125I-ET-1 binding activity in COS cells transfected with pools of a porcine cerebellum cDNA expression library. Two independent clones (pPCETR 1.1 and pPCETR 5.6) were identified and isolated by repeated rounds of pool enrichment and COS cell expression. DNA sequence analysis of pPCET 1.1 and pPCET 5.6 indicated that both clones have the same nucleotide sequence; the deduced amino acid sequence indicated that the porcine cerebellum ETR is 443 residues in length and consists of seven potential transmembrane domains, with homology to members of the GTP-binding protein-coupled receptor superfamily. Northern analysis indicated a single mRNA species of about 5 kilobases, which is expressed significantly in cerebellum, lung, kidney, and pituitary. Expression of functional receptor was demonstrated by endothelin-1 (ET-1)-mediated Ca2+ mobilization in COS cells transfected with pPCETR 1.1 (COS/ETR 1.1) and ET-1-mediated electrophysiological responses in Xenopus oocytes injected with RNA derived from pPCETR 1.1. Quantitative comparison of saturation binding of 125I-ET-1 to either porcine cerebellum or COS/ETR 1.1 membranes indicated an identical apparent dissociation constant. The relative efficacy of ET-related peptides to compete for binding of 125I-ET-1 to receptor from porcine cerebellum and COS/ETR 1.1 indicated that both preparations encode a nonselective or ETBR subtype. Chemical cross-linking of 125I-ET-1 to receptor derived from cerebellum or COS/ETR 1 revealed two bands, with apparent molecular masses of 47 and 35 kDa. These data demonstrate that the pPCETR 1.1 encodes the major ETR subtype in the porcine cerebellum.  相似文献   
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