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61.
The HLA-DRB1 and -DQB1 alleles in 161 healthy unrelated individuals, including Caucasians, Blacks and Mulattos (mixed Caucasian and Black), from the Northeastern region of the state of S?o Paulo, Brazil were analysed. The 36 different DRB1 alleles detected included not only common Caucasian alleles, but also DRB1*0411, 0807 and 1402, typical of Amerindians, and DRB1*0302, 1503, and 0804, typical of African American Blacks.  相似文献   
62.
Research Institute of Experimental Diagnosis and Treatment of Tumors, Oncologic Scientific Center, Russian Academy of Medical Sciences, Moscow. Troitsk Branch, I.V. Kurchatov Institute of Atomic Energy, Moscow Region. (Presented by Academician of the Russian Academy of medical Sciences, N. N. Trapeznikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 113, No. 6, pp. 636–638, June, 1992.  相似文献   
63.
Children with malignancy are immunosup-pressed and susceptible to serious infections with herpesviruses. The majority of children on chemotherapy for malignancy are seropositive for human herpesvirus-6 (HHV-6), and although HHV-6 has been demonstrated to be a pathogen in severely immunocompromised patients, whether this is the case for paediatric oncology patients is unknown. HHV-6 is secreted in saliva and in this study samples were examined prospectively for HHV-6 DNA in healthy children and those with malignancy. In a nested polymerase chain reaction (PCR), a 287 bp outer fragment and 163 inner fragment of HHV-6 DNA were amplified. The resulting amplimer contained a Hind III restriction site present only in “B” type HHV-6 and this was used to identify the type of HHV-6 amplified. In saliva from healthy control children, 74% (28/38) of samples were HHV-6 DNA-positive in either the supernate, pellet or both. In the patients, 58% (45/77) of all samples were HHV-6 DNA-positive. When sequential samples from twelve patients were examined the children appeared to fall into two groups: those who were frequently HHV-6 DNA-positive (60% of samples or more) and those who were rarely HHV-6 DNA-positive (33% of samples or less) (P < 0.0001). The only apparent difference between these two groups was that the less frequently HHV-6-positive group was more often febrile and unwell with neutro-paenia. Hind III digestion demonstrated all the positive samples to be “6” type HHV-6. Possible explanations for this difference in HHV-6 secretion between the patient groups are discussed. © Wiley-Liss, Inc.  相似文献   
64.
The dopamine hypothesis of schizophrenia proposed that dopaminergic pathways are involved in the etiology of the disease. In particular, interest among psychiatrists has focused on the D2 receptor because of its affinity to antipsychotic drugs. Recently a new dopamine receptor gene has been cloned, and named the dopamine D3 receptor. The D3 receptor is a potential site for antipsychotic drug action and may be involved in the pathophysiology of schizophrenia. We have carried out a linkage study between the susceptibility gene for schizophrenia and polymorphism of the dopamine D3 receptor gene in two Japanese pedigrees. The LOD scores were negative for, all genetic models and for all affective status at a recombination fraction θ = 0. Linkage of DRD3 has been excluded for the model 1 (dominant model) and the model13 (recessive model). The LOD score was - 3.43 at θ = 0 for model 1 (dominant model) and broad definition of affected status. These results were consistent with previous studies. © 1994 Wiley-Liss, Inc.  相似文献   
65.
A combination of the polymerase chain reaction and a novel ELISA-type DNA colourimetric assay (developed from studies with a retrovirus from man) was used in a preliminary study to detect DNA from avian infectious laryngotracheitis virus. The method is sensitive, specific and easy to perform. Since it can be readily adapted for the detection of DNA from other sources it could be useful for the identification of a variety of pathogens from other species of veterinary importance.  相似文献   
66.
The effect of solubilization of deoxyribonucleoproteins (DNP) in a medium of near-physiological ionic strength after treatment with the mutagen N-nitroso-N-methylurea (NMU) is highly dependent on the NMU concentration. To convert DNP into a soluble state, the critical number of groups in the DNA and protein must evidently be modified. On the basis of data obtained by the circular dichroism method and by viscosimetry it is concluded that after treatment with NMU the DNP complex becomes soluble in solvents with near-physiological ionic strength largely as a result of labilization and dissociation of the DNA-protein bonds.Laboratory of Biophysics, Institute of Medical Genetics, Academy of Medical Sciences of the USSR. Sector of Kinetics of Chemical and Biological Processes, Institute of Chemical Physics, Academy of Sciences of the USSR. Laboratory of Physical Methods of Investigation, D. I. Ivanovskii Institute of Virology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR S. S Debov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 6, pp. 674–677, June, 1976.  相似文献   
67.
DNA cloned from the ayw subtype of hepatitis B virus   总被引:4,自引:0,他引:4  
DNA from the ayw subtype of hepatitis B virus (HBV) was ligated into the EcorI site of DNA from plasmid pBR322 and propagated in E coli chi 776. A plasmid with a 3200 base pair insert (pHBV-1) was isolated and the cloned HBV DNA was mapped with restriction endonucleases. Differences were found in restriction endonuclease cleavage sites for DNAs from HBV of subtype ayw and adr.  相似文献   
68.
Effect of pancreatic lipase on supramolecular DNA complexes, nuclear matrix, and 70% ethanol-fixed cells is studied by elastoviscosimetry. It is shown that lipase induces DNA degradation not onlyin vitro but also in whole cells. Possible role of neutral lipids, in particular, DNA-bound diglycerides, in the arrangement of chromosomal DNA is discussed. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 12, pp. 635–639, December, 1997  相似文献   
69.
The effects of long-term smoking on mitochondrial DNA (mtDNA) deletions in hair follicles were investigated in subjects with different antioxidant capacity. Twenty-two male smokers with a smoking index of greater than 5 pack-years and without any known systemic diseases were recruited for this study. Forty healthy nonsmoking males were included as controls. We found that the concentrations of ascorbate and alpha-tocopherol and the activities of glutathione S-transferase (GST) and glutathione peroxidase in blood plasma were significantly decreased in smokers. The levels of glutathione and protein thiols in whole blood and the incidence of a 4,977 bp deletion of mtDNA (dmtDNA) in hair follicles were significantly increased in smokers. A significantly higher incidence of the 4,977 bp dmtDNA was found in smokers with plasma GST activity less than 5.66 U/l (OR = 7.2, P = 0.020). Using multiple covariate ANOVA and logistic regression, we found that age and low plasma GST activity were the only two risk factors for the 4,977 bp dmtDNA. These results suggest that smoking depletes antioxidants and causes mtDNA deletions and that plasma GST may play an important role in the preservation of the mitochondrial genome in tissue cells of smokers.  相似文献   
70.
Although there is a safe, inexpensive and efficacious vaccine against yellow fever, vaccination against other flavivirus diseases is less successful. There is no licensed vaccine against dengue fever and current vaccines against tick-borne encephalitis (TBE) and Japanese encephalitis are expensive and require several injections. Furthermore novel vaccines containing only virus envelope proteins may raise fears over antibody mediated enhancement (ADE) of disease. Here we report the successful use of genetic vaccination against TBE in an experimental animal model using a plasmid containing the coding sequence of a non-structural protein (NS1). Such vaccines would provide inexpensive protection against disease, without raising concerns over inducing ADE on subsequent exposure to heterotypic infectious virus. Attempts to generate chaemeric plasmids to protect against both TBE and dengue fever were less successful. Although these chaemeric plasmids directed the synthesis and secretion of the virus NS1 protein normally, no protection was observed against either TBE or dengue fever.  相似文献   
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