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101.
Computed tomography (CT) was performed in 189 individuals: in 44 children of schizophrenic parents (high risk group, HRG), in 39 parents with schizophrenia or with schizophrenic disturbance, in 56 children with schizophrenia, in 50 children with consequences of early organic damages of central nervous system (mental retardation syndrome and generalized tic syndrome). The frequency of CT changes was equal in the mentioned groups but their character was quite different. The widening of brain's liquor system (89.7%), the signs of frontal and temporal atrophia (31%), foci of decreased density of cerebral brain's matter, closer in subcortical ganglia and periventricular zone, and different anomalies of brain were observed in HRG children.  相似文献   
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OBJECTIVE: To predict the risk of extracapsular extension and postoperative recurrence before radical prostatectomy (RP) for prostate cancer. METHODS: We performed multivariate Cox regression analysis on preoperative variables in 260 clinically localized prostate cancer patients who underwent RP. With these data, we constructed a relative risk of recurrence (Rr) equation and an equation to predict the probability of extracapsular extension (PECE) before RP. RESULTS: Rr is calculated as exp[(0.47 x race + 0.14 x PSAST) + (0.13 x worst biopsy Gleason sum) + (1.03 x stage T1c) + (1.55 x stage T2b,c)], where PSAST indicates a sigmoidal transformation of prostate-specific antigen. PECE is calculated as 1/[1 + exp(-Z)], where Z = -2.47 + 0.15 (PSAST) + 0.31 (worst biopsy Gleason sum) + 0.18 (race) + 0.16 (stage T1c) + 0.38 (stage T2b,c). CONCLUSION: These two equations can be used preoperatively to predict the probability of extracapsular disease and the risk of prostate-specific antigen recurrence in patients undergoing RP.  相似文献   
103.
PURPOSE: Despite its common use as an indicator of apoptosis, little is known about the mechanisms controlling apoptotic DNA fragmentation in irradiated cells. This review discusses the pathways of chromatin fragmentation, and the role of both nucleases and chromatin structure in this process. DEFINITIONS: DNA fragmentation linked to apoptosis is a combination of cleavage events excising both large DNA fragments within the range 0.4-1.0 Mbp and 50 kbp followed by random cuts within internucleosomal regions (i.e. DNA laddering). The first two cleavage steps can be detected in virtually all apoptotic cells, but DNA laddering is not ubiquitously observed. Endonucleases that mediate this cleavage of chromatin may be classified by substrate specificity, mode of DNA cleavage and their cofactor requirements. CONCLUSIONS: Three major pathways of DNA fragmentation are proposed and discussed: (1) upregulation of endonucleases, (2) their intranuclear/intracellular redistribution and (3) primary changes of chromatin structure.  相似文献   
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In contrast to cytotoxic agents inducing rapid cell death, biological agents such as hormones, vitamins (e.g., retinoids), cytokines, and antireceptor antibodies act slowly and may alter ratios between cell growth and programmed cell death (apoptosis). We showed previously that anti-interleukin 6 (IL-6) and antitransferrin (Tf) receptor antibodies inhibited in vitro growth and induced death of myeloma cells. Retinoids also inhibit in vitro growth of human cancer cells and decrease IL-6 receptor display and autosecretion by some myeloma cells. Retinoids may also antagonize in vitro growth-promoting effects of iron and transferrin. To develop a novel strategy for treating myeloma, we examined antiproliferative and cytotoxic effects of retinoids in combination with anti-Tf or anti-IL-6 receptor antibodies. Myeloma cell lines were cultured with retinoids with or without anti-growth factor receptor monoclonal antibodies. Both all-trans retinoic acid (ATRA) and 13-cis-retinoic acid showed variable, dose-dependent inhibition of myeloma cell line growth. ATRA also induced significant down-regulation of myeloma IL-6 receptors and inhibited IL-6 autosecretion by myeloma cells. Antiproliferative effects of ATRA were increased by coculture with anti-Tf but not anti-IL-6 receptor antibodies. Colony-forming assays showed that antiproliferative effects of anti-Tf receptor antibodies were largely reversible, but 1 microM ATRA was cytotoxic to myeloma cells. To assess apoptosis, a flow cytometry assay detecting DNA damage was used. Using previously studied cell line models, flow cytometry detected programmed cell death induced by transforming growth factor beta1 in leukemia cells and by anti-growth factor receptor antibody treatment of IL-6-dependent myeloma cells, treatments which caused only modest increases in the percentage of cells undergoing morphological apoptosis and increased internucleosomal DNA degradation. Flow cytometry analysis of ATRA and anti-Tf antibody-treated myeloma cells also showed evidence for apoptosis induced by ATRA, but not with anti-Tf receptor antibodies. These changes were apparent several days before detection of internucleosomal DNA degradation on agarose gels in 8226 cells but were not detected at any time in U266 cells, which underwent cell death but showed no DNA damage using flow cytometry or degradation on agarose gels. Retinoids merit further study as possible maintenance or chemoprevention therapies for clonal plasma cell disorders and for treating paraneoplastic disorders such as Castleman's disease. Flow cytometry rapidly detects apoptosis induced by biological agents and may be useful for in vitro screening of novel biological therapies.  相似文献   
106.
The induction of human immunodeficiency virus (HIV)-specific T-cell responses is widely seen as critical to the development of effective immunity to HIV type 1 (HIV-1). Plasmid DNA and recombinant fowlpox virus (rFPV) vaccines are among the most promising safe HIV-1 vaccine candidates. However, the immunity induced by either vaccine alone may be insufficient to provide durable protection against HIV-1 infection. We evaluated a consecutive immunization strategy involving priming with DNA and boosting with rFPV vaccines encoding common HIV-1 antigens. In mice, this approach induced greater HIV-1-specific immunity than either vector alone and protected mice from challenge with a recombinant vaccinia virus expressing HIV-1 antigens. In macaques, a dramatic boosting effect on DNA vaccine-primed HIV-1-specific helper and cytotoxic T-lymphocyte responses, but a decline in HIV-1 antibody titers, was observed following rFPV immunization. The vaccine regimen protected macaques from an intravenous HIV-1 challenge, with the resistance most likely mediated by T-cell responses. These studies suggest a safe strategy for the enhanced generation of T-cell-mediated protective immunity to HIV-1.  相似文献   
107.
Phospholipase C-gamma1 (PLC-gamma1) mediates signals from various extracellular origins to evoke cellular events such as mitogenesis. Previously, we reported that PLC-gamma1 was highly expressed in colorectal cancer and familial adenomatous polyposis, suggesting that PLC-gamma1 might be oncogenic. In this study, we have established rat 3Y1 fibroblasts that overexpress whole PLC-gamma1 and src homology 2 (SH2)-SH2-SH3 domain of PLC-gamma1. These cells showed a transformed phenotype and were tumorigenic when transplanted into nude mice. These results indicate that overexpression of PLC-gamma1 could transform rat fibroblasts, and the transformation is mediated by SH2-SH2-SH3 domain of PLC-gamma1.  相似文献   
108.
Considering communication and leadership, authors examine the role of the leader as a focus of reception and transmission of information, based on the classification of Mintzberg related to their informative roles, such as the leader acting as monitor, disseminator and spokesman. Contextualizing this approach in the scenery of nursing management, authors study the dimension of nurses-leaders role as an essential element of communication in the systems of organization of nursing care.  相似文献   
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