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951.
Recognition of mycobacteria by the innate immune system is essential for the development of an adaptive immune response. Mycobacterial antigens stimulate antigen presenting cells (APCs) through distinct Toll-like receptors (TLRs) resulting in rapid activation of the innate immune system. The role of TLRs during infection with Mycobacterium bovis Bacillus Calmette-Guérin (BCG) has been evaluated for TLR2 and TLR4 only. Surprisingly, despite the fact that immune stimulatory CpG-motifs have been originally derived from BCG, for the vaccine strain the role of TLR9 has not been addressed before. To identify the set of TLRs involved in the recognition of BCG, we infected bone marrow-derived macrophages and bone marrow-derived dendritic cells (Flt3-ligand generated DCs) from TLR2, TLR3, TLR4, TLR7, TLR9, MyD88 knockout, TLR2/4 and TLR2/4/9 multiple knockout mice. The degree of activation and stimulation was determined by TNFα, IL-6 and IL-12p40 ELISA. Activation of DCs was measured by surface expression of the costimulatory molecule CD86. We observed the most dramatic reduction of the inflammatory response for TLR2-deficient antigen presenting cells. Both macrophages and DCs produce markedly decreased amounts of TNFα and IL-6 in the absence of TLR2 whereas no significant reduction could be observed for TLR3, 4, 7, 9 single TLR-knockouts. However, IL-12 production in DCs appears not exclusively dependent on TLR2 and only in TLR2/4/9-deficient DCs BCG-induced IL-12 is reduced to background levels. Similarly, up-regulation of CD86 is abolished only in TLR2/4/9-deficient DCs supporting a role of TLR9 in the recognition of M. bovis BCG by murine dendritic cells.  相似文献   
952.
The permanent human cell line C3842 was established from a secondary chondrosarcoma in a typical case of Olliers disease. In the present study, we analyzed the morphological, cytogenetic and molecular biological characteristics of the cultured cells in comparison with the original tumor and investigated the invasion properties of the tumor model using functional imaging of proteolysis, matrigel assay and chick chorioallantoic membrane assay. C3842 cells exhibit the typical features of malignant cartilage tumor cells in vitro, including the expression of collagen types II, IX, XI and aggrecan. The proteolytic ability of C3842 cells is attributed to the expression of several proteases, such as cathepsin B, urokinase plasminogen activator and matrix-metalloproteinase-2, which enable the cells to degrade collagen type I and to permeate matrigel matrix. In accordance with the biological features in vivo, C3842 cells are not able to invade through the epithelium of the chick chorioallantoic membrane. In conclusion, the cell line C3842 provides the first model of a secondary chondrosarcoma in Olliers disease in vitro, which is characterized by distinct features of such malignant cartilage tumors.  相似文献   
953.
954.
Cytomegalovirus (CMV), a common cause of pneumonia in immunocompromised subjects, is conventionally diagnosed in the laboratory by tube cell culture assays or by detection of characteristic inclusions in histologic sections. Of 160 immunocompromised patients, CMV infection was diagnosed in 19 subjects by bronchoalveolar lavage (BAL), using a monoclonal antibody directed against an early nuclear antigen of the virus. Cytospin preparations from BAL and MRC-5 cell cultures inoculated with the BAL specimens yielded positive results for 6 (31.6%) and 18 (94%) of the 19 subjects, respectively, within hours of the bronchoscopic procedure, whereas conventional tube cell cultures were positive for 11 of the 19 subjects (57.9%) only after an average of 9.3 days. The monoclonal antibody method permitted easy and rapid detection of CMV in BAL specimens.  相似文献   
955.
Parathyroid hormone-related protein (PTHrP) is invoked as the cause of humoral hypercalcaemia of malignancy (HHM); it is contained in the keratinocyte layer of normal skin; and there is evidence that is is produced by fetal parathyroids. Antibodies against synthetic PTHrP peptides have been raised in rabbits and sheep. This immunohistochemical study has found that primary parathyroid adenomata and hyperplastic glands from patients with chronic renal failure stain positively with antisera against PTHrP(1-34) and PTHrP(50-69). Primary hyperplastic glands are negative. No staining with anti-PTHrP(106-141) antiserum could be detected immunohistochemically in any of the parathyroid adenomata or hyperplasia.  相似文献   
956.
In a laboratory study of psychomotor sensitivity to alcohol, twins were asked “Would you drive a car now?” at 1, 2, and 3 h after drinking a standard dose of ethanol (0.75 g/kg). Correlations among these binary items, the Eysenck personality scales, and age were investigated using PRELIS and LISREL. Willingness to drive and Extraversion correlate at all three times in both males and females. In males, willingness to drive also correlates with Psychoticism, and in females it correlates negatively with the Lie (or Social Desirability) scale. Most correlations between cotwins in willingness to drive were significant in both monozygotic (MZ) and dizygotic (DZ) male twins but correlations were lower in female twins. Factor and Markovian models were fitted. In males there seem to be both genetic and cultural influences on willingness to drive when drunk. About half the genetic variance seems to be the pleiotropic effects of genes influencing Extraversion. The correlationswith Psychoticism, on the other hand, seem to be largely environmental in origin. The small sample size and lack of proper significance tests mean that these results must be interpreted with caution.  相似文献   
957.
This paper reports the results of a postal questionnaire completed by 2343 smokers who had contacted a television company for help with stopping smoking. Of these, 1848 (78.9%) completed a follow-up questionnaire 1 year later. This indicated that 797 had tried to stop, 709 had tried to cut down, and 164 had become abstinent. Analyses show that the intention to try to stop smoking was dependent not only on the perceived health benefit, but also on the subjects' confidence that they would succeed if they tried to stop. As predicted by Weiner's [(1979). J. Educ. Psychol.71: 3–25] model of achievement motivation, those who attributed other smokers' failures at quitting to stable factors had lower expectancies of success, as had those who saw themselves as more addicted. When the follow-up data are considered, reported attempts at quitting were strongly related to previously declared intentions, and reported abstinence was related to previous confidence (expectancy of success) and perceived addiction. There is no support for hypotheses concerning self-other differences in attribution, or defensive attribution, in subjects' attributions for their own failures at cessation. Implications for antismoking interventions are discussed.This research was facilitated to various extents by grants from the British Council, the Department of Health and Social Security, the Medical Research Council, and the Social Science Research Council, London. When the data were collected, all authors were at the Addiction Research Unit, Institute of Psychiatry, University of London.  相似文献   
958.
Nomarski optics were used to identify stages of the spermatogenic cycle of seminiferous tubules in sectioned tissue or in whole dispersed tubules and to characterize the equine spermatogenic wave. Embedded tissues were sectioned at 20 microns. Whole dispersed tubules were obtained by enzymatic digestion of thin slices of fresh testis. Dispersed tubules were fixed, dehydrated in graded levels of alcohol, infiltrated with Epon, and mounted in toto on glass slides. Stages of the spermatogenic cycle could be identified under Nomarski optics in both histologic sections and tubules mounted in toto. Stage dependent nuclear chromatic and cytoplasmic changes in spermatogonia, spermatocytes, and spermatids were evident. Spermatid development included chromatin condensation, nuclear elongation, acrosomal development from the Golgi and proacrosomic granules, migration of the annulus and mitochondrial alignment, and the transient appearance of the chromatoid body and manchette. Both nuclear and cytoplasmic details of Sertoli cells were revealed. In tubules mounted in toto, the spermatogenic wave along the length of the tubules occurred as a consecutive set of stages occupying small regions along the tubular length. The spermatogenic wave in the horse is more similar to that of humans than that of rats. The combination of enzymatic isolation of seminiferous tubules and identification of spermatogenic stages by Nomarski optics facilitates examination of the spermatogenic wave in species whose tubules are tightly bound and not easily teased apart.  相似文献   
959.
The nature of the relationship between social contact and attitude similarity between twins was investigated using longitudinal data from a sample of Australian twins. Earlier research has suggested that social attitudes are not explained solely by shared environment; rather there are both genetic and environmental components that explain variance in social attitudes. Using three types of analyses we investigated the magnitude of the relationship and the direction of causation between attitude similarity and social contact. Longitudinal analysis of within-pair variance by level of contact suggests that attitude similarity leads to contact among the females and that similarity is both genetically and environmentally based. Analyses using a crosslag regression model suggest that similarity causes contact among MZ females. Biometrical analyses indicate differences in direction of causation for males and females. Among females, both genetic and shared environmental parameter estimates could be equated across contact groups, suggesting little relationship between contact and similarity. Among males, findings of smaller estimated heritability in the high-contact group suggest that similarity causes contact. However, an increased estimate of the contribution of shared environmental variance in the high-contact males could additionally suggest that contact leads to similarity.  相似文献   
960.
Interactions between the carbonyl and amino groups in copolymers of 2-dimethylaminoethyl methacrylate with N-phenylmaleimide are reported. The existence of interactions ensues from potentiometric measurements and UV-VIS spectra. Interactions in these copolymers result in the formation of energetically very advantageous chromophores, reflected in an intense red colour of the substances obtained.  相似文献   
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