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41.
The configurations of immunoglobulin, T-cell receptor beta chain and bcl-2 genes were analyzed in lympho-proliferative disorders using nonradioactive digoxigenin-labeled probes. The studies demonstrated the reliability of digoxigenin-labeled probes for the detection of single-copy genes after Southern blotting of genomic DNA: 1 microgram and sometimes even 0.2 microgram of restriction endonuclease-digested DNA could be detected either by JH, C beta or bcl-2 probes. The intensity of the signal was consistently satisfactory, and there was no background problem. Control experiments showed neither false-positive nor false-negative results caused by the use of the nonradioactive detection system.  相似文献   
42.
The phylogenetic position of the Pedetidae, represented by a single species Pedetes capensis, is controversial, reflecting in part the retention of both Hystricomorphous and Sciurognathous characteristics in this rodent. In an attempt to clarify the species evolutionary relationships, mtDNA gene sequences from 10 rodent species (representing seven families) were analyzed using phenetic, parsimony, and maximum-likelihood methods of phylogenetic inference; the rabbit, Oryctolagus cuniculus (Order Lagomorpha), and cow, Bos taurus (Order Artiodactyla), were used as outgroups. Investigation of 714 base pairs of the protein-coding cytochrome b gene indicate strong base bias at the third codon position with significant rate heterogeneity evident between the three structural domains of this gene. Similar analyses conducted on 816 base pairs of the 12S rRNA gene revealed a transversion bias in the loop sections of all taxa. The cytochrome b gene sequences proved useful in resolving associations between closely related species but failed to produce consistent tree topologies at the family level. In contrast, phylogenetic analysis of the 12S rRNA gene resulted in strong support for the clustering of Pedetidae/Heteromyidae/Geomyidae and Muridae in one clade to the exclusion of the Hystricidae/Thryonomyidae and Sciuridae, a finding which is concordant with studies of rodent fetal membranes as well as reproductive and other anatomical features.   相似文献   
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A prophylactic vaccine for genital herpes disease remains an elusive goal. We report the results of two studies performed collaboratively in different laboratories that assessed immunogenicity and vaccine efficacy in herpes simplex virus 1 (HSV-1)-seropositive guinea pigs immunized and subsequently challenged intravaginally with HSV-2. In study 1, HSV-2 glycoproteins C (gC2) and D (gD2) were produced in baculovirus and administered intramuscularly as monovalent or bivalent vaccines with CpG and alum. In study 2, gD2 was produced in CHO cells and given intramuscularly with monophosphoryl lipid A (MPL) and alum, or gC2 and gD2 were produced in glycoengineered Pichia pastoris and administered intramuscularly as a bivalent vaccine with Iscomatrix and alum to HSV-1-naive or -seropositive guinea pigs. In both studies, immunization boosted neutralizing antibody responses to HSV-1 and HSV-2. In study 1, immunization with gC2, gD2, or both immunogens significantly reduced the frequency of genital lesions, with the bivalent vaccine showing the greatest protection. In study 2, both vaccines were highly protective against genital disease in naive and HSV-1-seropositive animals. Comparisons between gD2 and gC2/gD2 in study 2 must be interpreted cautiously, because different adjuvants, gD2 doses, and antigen production methods were used; however, significant differences invariably favored the bivalent vaccine. Immunization of naive animals with gC2/gD2 significantly reduced the number of days of vaginal shedding of HSV-2 DNA compared with that for mock-immunized animals. Surprisingly, in both studies, immunization of HSV-1-seropositive animals had little effect on recurrent vaginal shedding of HSV-2 DNA, despite significantly reducing genital disease.  相似文献   
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Background  

Glutathione, the main antioxidant of intestinal epithelial cells, is suggested to play an important role in gut barrier function and prevention of inflammation-related oxidative damage as induced by acute bacterial infection. Most studies on intestinal glutathione focus on oxidative stress reduction without considering functional disease outcome. Our aim was to determine whether depletion or maintenance of intestinal glutathione changes susceptibility of rats to Salmonella infection and associated inflammation.  相似文献   
47.
Several studies examined the fine-scale structure of human genetic variation in Europe. However, the European sets analyzed represent mainly northern, western, central, and southern Europe. Here, we report an analysis of approximately 166,000 single nucleotide polymorphisms in populations from eastern (northeastern) Europe: four Russian populations from European Russia, and three populations from the northernmost Finno-Ugric ethnicities (Veps and two contrast groups of Komi people). These were compared with several reference European samples, including Finns, Estonians, Latvians, Poles, Czechs, Germans, and Italians. The results obtained demonstrated genetic heterogeneity of populations living in the region studied. Russians from the central part of European Russia (Tver, Murom, and Kursk) exhibited similarities with populations from central–eastern Europe, and were distant from Russian sample from the northern Russia (Mezen district, Archangelsk region). Komi samples, especially Izhemski Komi, were significantly different from all other populations studied. These can be considered as a second pole of genetic diversity in northern Europe (in addition to the pole, occupied by Finns), as they had a distinct ancestry component. Russians from Mezen and the Finnic-speaking Veps were positioned between the two poles, but differed from each other in the proportions of Komi and Finnic ancestries. In general, our data provides a more complete genetic map of Europe accounting for the diversity in its most eastern (northeastern) populations.  相似文献   
48.
The association of ovarian carcinoma risk with the polymorphism rs1271572 in the estrogen receptor beta (ESR2) gene was examined in 4946 women with primary invasive ovarian carcinoma and 6582 controls in a pooled analysis of ten case-control studies within the Ovarian Cancer Association Consortium (OCAC). All participants were non-Hispanic white women. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression adjusted for site and age. Women with the TT genotype were at increased risk of ovarian carcinoma compared to carriers of the G allele (OR = 1.10; 95%; CI: 1.01–1.21; p = 0.04); the OR was 1.09 (CI: 0.99–1.20; p = 0.07) after excluding data from the center (Hawaii) that nominated this SNP for OCAC genotyping A stronger association of rs1271572 TT versus GT/GG with risk was observed among women aged ≤50 years versus older women (OR = 1.35; CI: 1.12–1.62; p = 0.002; p for interaction = 0.02) that remained statistically significant after excluding Hawaii data (OR = 1.34; CI: 1.11–1.61; p = 0.009). No heterogeneity of the association was observed by study, menopausal status, gravidity, parity, use of contraceptive or menopausal hormones, tumor histological type, or stage at diagnosis. This pooled analysis suggests that rs1271572 might influence the risk of ovarian cancer, in particular among younger women.  相似文献   
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To study whether absolute (m/s) or relative (body lengths/s) speed should be used to compare the vulnerability of differently sized animals, we developed a simple computer simulation. Human 'predators' were asked to 'catch' (mouse-click) prey of different sizes, moving at different speeds across a computer screen. Using the simulation, a prey's chances of escaping predation depended on its speed (faster prey were more difficult to catch than slower prey of the same body size), but also on its size (larger prey were easier to catch than smaller prey at the same speed). Catching time, the time needed to catch a prey, also depended on both prey speed and prey size. Relative prey speed (body lengths/s or body surface/s) was a better predictor of catching time than was absolute prey speed (m/s). Our experiment demonstrates that, in contrast to earlier assertions, per unit body length speed of prey may be more 'ecologically relevant' than absolute speed. Copyright 1998 The Association for the Study of Animal Behaviour.  相似文献   
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