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R Banik  D Lubach 《Dermatologica》1987,174(4):180-183
The relevant literature does not contain detailed numerical data about skin tags. We found 46% skin tag carriers in 750 unselected persons (25% males and 21% females). The risk of getting skin tags increases with age. The age of 50, however, seems to be a turning point, at which a stagnation of the increase is observed. The majority of the carriers had no more than 3 tags per localization; the most frequent localization was the axilla, followed by the neck. This study supplies objective data for the evaluation of skin tags as markers for colonic polyps and may provide standard values for future studies.  相似文献   
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Epidemiological studies have indirectly linked compounds ofchromium, nickel and arsenic to human carcinogenesis. However,there is no evidence that metal compounds can transform humancells to the tumorigenic phenotype in culture. We show herethat exposure to 36 µM NiS04 for 48–96 h resultsin transformation of an immortal, non-tumorigenic, osteoblast-likecell line, HOS TE85, to the tumorigenic phenotype. Continuouspassaging following treatment leads to the formation of a fewdense foci. The cells isolated and expanded from the foci aremorphologically transformed, and form anchorage-independentcolonies of the size and abundance comparable to that formedby Kirsten murine sarcoma virus transformed HOS TE85 cells.The transformed cells from tumors in nude mice, have enhancedlevels of plasminogen activators and have lost the ability toform model bone matrix on extended culture in the presence ofascorbic acid and ß-glycerophosphate. A number ofcell lines have been established from nude mouse tumors. Cytogeneticanalysis reveals 16 marker chromosomes and an aberrant chromosome16. This is the first report of the transformation of a humancell line to tumorigenic phenotype by a metal carcinogen.  相似文献   
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118 multibacillary leprosy patients with differential manifestations were studied for the antigens they expressed at MHC loci to investigate the role of human leukocyte antigens in the differential response to the same causative agent. While the lepromatous leprosy (LL) patients showed a significant increase of Bw60, DR2, DRw8 and DQw1, borderline lepromatous (BL) patients had Bw52, DR9 and DQw7 significantly more often as compared to the normal controls. A comparison of LL, BL and mid-borderline (BB) patients showed a significantly higher frequency of Bw60 in LL patients as compared to the BL. However, Bw52, Bw53, DR9 and DQw7 were found significantly more often in the BL patients as compared to the LL patients but the difference failed to reach significance after pc. A comparison of HLA antigens in BB patients with those of either the LL or BL patients did not show any significant differences.  相似文献   
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PurposeNoroviruses are common viral agents in acute diarrhea in all age groups worldwide. Norovirus has been classified into 10 genogroups, GI to GX with over 48 genotypes among them the GII.4 genotype has evolved over time with a clear pattern of periodic variant replacement. Immunity is strain or genotype specific with little or no protection conferred across genogroups. The present study was aimed to determine the epidemiology, prevalent genotypes of norovirus in children below five years of age in the Hyderabad region, India.MethodsThe stool samples and clinical data were collected from 458 children below 5 years of age comprising of cases with acute gastroenteritis (n ?= ?366) and a control group (n ?= ?92) admitted to the pediatric ward. All the samples were tested for Norovirus by ELISA and RT-PCR. Sequencing was done for predominant strains.Results10.3% (n ?= ?38) of cases and 3.2% (n ?= ?3) of the control group were found to be Norovirus positive. Predominant genotypes were GII-82.5% followed by GI-12.5%.ConclusionSequencing and Phylogenetic analyses of 20 GII.4 strains was done. All of the isolates are clustered away from published the GII.4 variants thus suggesting the appearance of a new variant.  相似文献   
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Carrier analysis and prenatal diagnosis of haemophilia A in North India   总被引:4,自引:0,他引:4  
The feasibility of DNA diagnosis for haemophilia A in North India was evaluated using intragenic polymorphic DNA markers in factor VIII gene for linkage analysis as well as direct detection of inversion mutation in intron 22 of the gene. The informativity of RFLP (HindIII, BclI and XbaI) and STR (introns 13 and 22) markers for linkage analysis in factor VIII gene was determined in 100 normal individuals. The observed heterozygosity for RFLP markers HindIII, BclI and XbaI was 0.63, 0.60 and 0.48 while that of STR markers introns 13 and 22 were 0.60 and 0.40 respectively. Six and four alleles were identified for introns 13 and 22 and the most frequent allele was 13(CA)26 and 22(AG)n(GT)26 with an allele frequency of 0.53 and 0.62 respectively. The heterozygosities observed for RFLP markers was higher (>70%) than the STR markers (50%) in the affected families with haemophilia A. Inversion mutation was detected in 37% of severely affected patients. Based on present and previous studies from India, a strategy has been proposed to provide molecular diagnosis to a large number of undiagnosed cases of haemophilia A.  相似文献   
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Eye infections caused by adenovirus (Ad) often result in nosocomial infections and community epidemics with significant rates of morbidity. No antiviral agent effective against Ad is yet available for clinical use. Therefore, early diagnosis is still the mainstay for patient management and the prevention of epidemics. A multiplex PCR assay based on amplification of a combination of the fiber and hexon genes which can identify the six important oculopathogenic serotypes of Ads (Ad serotype 3[Ad3], Ad4, Ad7, Ad8, Ad19, and Ad37) in a single-tube amplification reaction was developed. Ad serotypes could be distinguished by the different amplicon sizes. The assay correctly identified prototype strains as well as isolates in clinical specimens. In comparison with a previously described PCR-restriction fragment polymorphism method, our assay gave unequivocal results for clinical specimens. Our multiplex PCR has the potential to serve as a rapid and cost-effective tool for the typing of important ocular Ads.  相似文献   
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