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11.
Gordon C. Brown Thomas Francis Jr. John Ainslie 《The Journal of experimental medicine》1948,87(1):21-27
The occurrence and duration of the carrier state in familial associates of recognized cases of poliomyelitis was studied by the examination for virus of stool specimens collected from the members of four families at regular intervals for a period of over 2 months. The results indicate that: (1) virus may persist in their stools continuously for 4 to 5 weeks; (2) virus may be encountered intermittently in the stools; (3) in some instances virus may be present for brief periods only; (4) children are more likely to maintain virus than are adults in the same family; (5) infection of a family takes place rapidly, suggesting again simultaneous infection from a common source. 相似文献
12.
The relation of infectious and hemagglutination titers to the adaptation of influenza virus to mice 总被引:6,自引:4,他引:2
WANG CI 《The Journal of experimental medicine》1948,88(5):515-519
The non-pathogenic (unadapted) line of the Rhodes strain of influenza virus multiplied readily in the mouse lung, but its rate of multiplication was slower and its hemagglutination titer attained at the peak of growth was much lower than that of the adapted line of the same virus. The implication of these findings to mouse adaptability of the virus is discussed. 相似文献
13.
Zhi-Qin Mao Mei Sun Department of Pediatrics Second Affiliated Hospital China Medical University Shenyang Liaoning Province China Ying Huang Hong Gao Department of Pediatric Surgery Second Affiliated Hospital China Medical University Shenyang Liaoning Province China Qiang Ruan Rong He Ying Qi Yu-Jing Huang Yan-Ping Ma Yao-Hua Ji Zheng-Rong Sun Virus Laboratory Second Affiliated Hospital China Medical University Shenyang Liaoning Province China 《World journal of gastroenterology : WJG》2007,(32)
AIM:To explore the genetic diversities of UL144 open reading frame (ORF) of cytomegalovirus DNA detected in colon tissue from infants with Hirschsprung's disease (HD) by sequencing UL144 DNA in 23 aganglionic colon tissue and 4 urine samples from 25 HD infants. METHODS:Nest PCR was performed for amplification of the UL144 gene. The UL144 gene was analyzed with softwares,such as DNAclub,BioEdit,PROSITE database,and DNAstar. RESULTS:The strains from HD patients were distributed among three genotypes of UL144:group 1A (64%),group 2 (24%),and group 3 (12%). The UL144 genotypes between strains from HD and control group were compared by chi square test (χ2 = 1.870,P = 0.393). Strains from the colon were sporadically distributed in UL144 genotypes. CONCLUSION:There are genetic diversities of UL144 ORF in colon tissue of infants with HD. However,cytomegalovirus UL144 genotypes are not associated with clinical manifestations of HD. 相似文献
14.
Human rhinoviruses: the cold wars resume. 总被引:1,自引:0,他引:1
Ian M Mackay 《Journal of clinical virology》2008,42(4):297-320
15.
Shobha Narahari Abida Juwle Subhankar Basak Dhananjaya Saranath 《Infection, genetics and evolution》2009,9(4):643-645
Viral hepatitis represents a major global health problem with 170 million Hepatitis C Virus (HCV) carriers worldwide, and 12–13 million HCV carriers in India. HCV genotypes are of clinical significance in indicating drug responsiveness and prognosis of the patient. The HCV genotypes are of epidemiologic significance as well, as they are indicative of transmission route of infection and have not been extensively studied in the Indian context. In the current study, HCV genotyping was examined in 2118 patients from different geographic regions of India. HCV was detected by PCR amplification of 5′ UTR and core-envelope1 regions, followed by genotyping using nucleotide sequencing and analysis with NCBI tool (http://www.ncbi.nlm.nih.gov/projects/genotyping/formpage.cgi). HCV genotype distribution in the 2118 Indian patients demonstrated prevalence of HCV3 (3a/3b primarily) in 62% and HCV1 (1a/1b primarily) in 31% patients. The predominance of HCV3 was significant in northern (p = 0.01) and eastern (p = 0.008) regions of India. HCV types 2, 4, 5, and 6 were detected in 0.05–4.5% of the patient group. Thus, our studies demonstrate HCV genotype prevalence in the cohort group in different regions of India. 相似文献
16.
17.
P P Mortimer 《Sexually transmitted infections》1995,71(2):109-119
Soon after its introduction in 1910, intravenous arsphenamine treatment for syphilis was found to be complicated by jaundice. The underlying cause, unsterile syringes and needles, was eventually recognised in the early 1940s, mainly through the efforts of British Army investigators. The infection most often transmitted was probably hepatitis B virus (HBV), but the high mortality in a few of the outbreaks of arsphenamine jaundice suggests that variants of HBV, or other hepatitis viruses, were sometimes involved. Fifty years later, at a time when there are estimated to be over three hundred million carriers of HBV in the world and probably at least as many hepatitis C virus carriers, and when the World Health Organisation estimates that there have been 17 million infections with human immunodeficiency virus, the lessons learnt around 1945 about the need to use sterile instruments and needles for all injections and venepunctures remain highly pertinent. 相似文献
18.
One hundred forty-nine specimens were tested in a LightCycler nested multiplex polymerase chain reaction (LCnmPCR) for Herpes simplex virus (HSV)1, HSV2, and VZV. Eighty-one were from genitourinary medicine (GUM) patients and the other 68 specimens were from other patients with skin lesions. The results were compared to a conventional multiplex nested PCR (nmPCR) using agarose gel electrophoresis. Twenty-five specimens were positive in both assays for HSV1 and 29 were positive for VZV. For HSV2 there were 27 positive in the LCnmPCR and 26 positive in the nmPCR assay. The melting temperatures (Tms) of each target were different with a mean of 84.75 degrees C for HSV1, 88.57 degrees C for HSV2, and 83.62 degrees C for VZV. The melting curves of positive specimens directly overlaid the melting curves of the positive controls in the assay. The LCnmPCR assay is a convenient alternative to conventional PCR using agarose gel electrophoresis. It improves specimen turnaround time by eliminating the need for gel electrophoresis, transillumination, and gel photography. It also shows increased sensitivity for HSV2 over our standard assay. This LCnmPCR reduces further the possibility of amplicon contamination with nested PCR protocols. 相似文献
19.
Evaluation of a new enzyme-linked immunosorbent assay test for rotavirus antigen in faeces 总被引:6,自引:0,他引:6 下载免费PDF全文
A new commercial test for the diagnosis of rotavirus gastroenteritis was assessed. With some modifications it compared favourably with electron microscopy and immunofluorescence. 相似文献
20.
Conclusions NT antibodies to LI virus were found in the sera of Swedish cows from many parts of the country although only exceptionally in the north. The prevalence of positive specimens increased markedly towards the southeast. This geographic distribution apparently fits well with the occurrence of ticks in the country. An analysis, now in progress, of RSSE-LI antibodies in human cases of meningoencephalomyelitis seems to indicate a closely similar distribution of the human RSSE infections. It is thus obvious that the screening of cow sera for LI antibodies provides reliable information as to endemic regions of RSSE-LI-like viruses. There was nothing to suggest that nonspecific reactions occurred or impaired the results; in fact the very uneven geographic distribution of positive specimens, of high as well as low titers, should argue for specificity of the reaction.Aided by a grant from the Swedish National Association against Poliomyelitis.The skilful technical assistance of MissSiri Austrin, MissIngrid Lövhvist, MissBrita Gustafson and Mr.Nils Lundh is gratefully acknowledged. 相似文献