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Evaluated and compared the support provided by family membersand friends for adolescents' diabetes care. Family and friendsupport also were examined in relation to other measures ofsocial support, to demographic variables (age, gender, durationof diabetes) and to adherence. Using a structured interview,74 adolescents with diabetes described the ways that familymembers and friends provided support for diabetes management(insulin shots, blood glucose monitoring, eating proper meals,exercise), and for helping them to "feel good about their diabetes."Families provided more support than friends for three managementtasks (insulin injections, blood glucose monitoring, meals);this support was largely instrumental. In contrast, friendsprovided more emotional support for diabetes than families.Greater family support was related to younger age, shorter diseaseduration, and better treatment adherence. Implications of thefindings include encouraging parents to remain involved in adolescents'treatment management, and involving peers as supportive companionsfor meals and exercise.  相似文献   
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Previously, our laboratory showed that Holstein cattle experimentally infected with Neospora caninum develop parasite-specific CD4+ cytotoxic T lymphocytes (CTL) that lyse infected, autologous target cells through a perforin-granzyme pathway. To identify specific parasite antigens inducing bovine CTL and helper T-lymphocyte responses for vaccine development against bovine neosporosis, the tachyzoite major surface proteins NcSAG1 and NcSRS2 were targeted. In whole tachyzoite antigen-expanded bovine T-lymphocyte lines, recombinant NcSRS2 induced potent memory CD4+- and CD8+-T-lymphocyte activation, as indicated by proliferation and gamma interferon (IFN-gamma) secretion, while recombinant NcSAG1 induced a minimal memory response. Subsequently, T-lymphocyte epitope-bearing peptides of NcSRS2 were mapped by using overlapping peptides covering the entire NcSRS2 sequence. Four experimentally infected cattle with six different major histocompatibility complex (MHC) class II haplotypes were the source of immune cells used to identify NcSRS2 peptides presented by Holstein MHC haplotypes. NcSRS2 peptides were mapped by using IFN-gamma secretion by rNcSRS2-stimulated, short-term T-lymphocyte cell lines, IFN-gamma enzyme-linked immunospot (ELISPOT) assay with peripheral blood mononuclear cells, and 51Cr release cytotoxicity assay of rNcSRS2-stimulated effector cells. Four N. caninum-infected Holstein cattle developed NcSRS2 peptide-specific T lymphocytes detected ex vivo in peripheral blood by IFN-gamma ELISPOT and in vitro by measuring T-lymphocyte IFN-gamma production and cytotoxicity. An immunodominant region of NcSRS2 spanning amino acids 133 to 155 was recognized by CD4+ T lymphocytes from the four cattle. These findings support investigation of subunit N. caninum vaccines incorporating NcSRS2 gene sequences or peptides for induction of NcSRS2 peptide-specific CTL and IFN-gamma-secreting T lymphocytes in cattle with varied MHC genotypes.  相似文献   
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We have studied an age-related impairment in angiogenesis and evaluated the effect of overexpressing VEGF in this situation. Polyvinyl alcohol sponges were implanted subcutaneously into aged (24-month), adult (12-month), and young (2-month) rats. Blood vessel ingrowth and proliferative activity in the sponges were assessed by histology with immunostaining for von Willebrand's factor and proliferating cell nuclear antigen (PCNA), respectively. The percentage of total sponge area filled with ingrowing fibrovascular tissue was minimal in aged rats, intermediate in adult rats and highest in young rats. A similar pattern was observed for the total blood vessel numbers in the sponges from old to young animals. The percentage of total sponge endothelial cells (ECs) showing proliferative activity (PCNA positive) was lowest in the aged animals, intermediate in the adult rats and highest in the young rats. To further explore the mechanism of impaired angiogenesis in aged animals, we investigated and found a reduced level of endogenous VEGF protein expression in 12-month-old rats compared to that in 2-month-old rats. VEGF121 gene transfer significantly enhanced blood vessel and fibrovascular tissue ingrowth in adult/aged rats. Adenoviral-VEGF gene transfer also significantly stimulated EC proliferation in aged and adult rats. However, identical treatment failed to further stimulate the already more robust angiogenesis in young animals. The different angiogenic response in adult vs. young rats was not due to differences in gene transfer efficiency, since similar levels of human VEGF121 protein was detected in adult and young rats. Our results indicate that the decreased angiogenic response with aging is associated with reduced EC proliferation and reduced endogenous VEGF production. Adenoviral-VEGF121 gene transfer is effective in augmenting angiogenesis, particularly in older animals.  相似文献   
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The effects of aging on sex differences in analgesia from the kappa-opioid agonist, U50,488H (U50), were examined in C57BL/6J mice. U50 analgesia can be blocked by the N-methyl-d-aspartate receptor antagonist, MK-801 (MK), in male rodents and gonadectomized females, but not hormonally intact or estrogen-replaced females, suggesting the existence of alternate neurochemical mediation in females. We now report that MK antagonism of U50 analgesia is age-dependent in females. That is, reproductively senescent females display MK-sensitive U50 analgesia qualitatively similar to that displayed by males or hormonally deprived young females. Age-related reductions in U50 analgesic magnitude were also observed in females. Thus, age and gender are likely to alter the clinical efficacy of analgesic drugs active at kappa-opioid receptors.  相似文献   
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FOXL2 mutations cause gonadal dysgenesis or premature ovarian failure (POF) in women, as well as eyelid/forehead dysmorphology in both sexes (the 'blepharophimosis-ptosis-epicanthus inversus syndrome', BPES). Here we report that mice lacking Foxl2 recapitulate relevant features of human BPES: males and females are small and show distinctive craniofacial morphology with upper eyelids absent. Furthermore, in mice as in humans, sterility is confined to females. Features of Foxl2 null animals point toward a new mechanism of POF, with all major somatic cell lineages failing to develop around growing oocytes from the time of primordial follicle formation. Foxl2 disruption thus provides a model for histogenesis and reproductive competence of the ovary.  相似文献   
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Several studies have shown that MIB-1 labeling indices correlate well with tumor grade and prognosis in a variety of tumor types. Several factors are responsible for some degree of variability in the determination of labeling indices. Interobserver variability is one of the factors often cited as responsible for this variability. A slide from each of 30 oligodendrogliomas, stained with MIB-1 antibody, was distributed to six pathologists. The same set of slides was reviewed by each individual. Each pathologist was instructed to determine a MIB-1 labeling index by evaluating 1,000 tumor cell nuclei from the area of the slide with the most staining. The labeling index record reflected a percentage of positive-staining tumor cells. Interobserver agreement was compared. MIB-1 labeling indices ranged from 0 to 45.7. Overall agreement was good (> or =0.75) with a concordance coefficient of 0.832 (confidence interval, 0.700 to 0.909). Variability was greater among tumors with higher labeling indices as compared with tumors with labeling indices closer to 0. The overall agreement of MIB-1 labeling indices, while not perfect, was good. The generally minor variability among observers may be related to differences in the area of the slide evaluated and in differing lower thresholds for interpreting positivity. Further improvement of concordance may theoretically be attainable by further training and discussion among observers.  相似文献   
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