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1.
This study examined the temporal concordance between the onset of childhood anxiety disorders and the points of onset and ending of child sexual abuse (CSA). Sexually abused children (N = 158) were assessed with structured diagnostic interviews. Onset ages for lifetime prevalence anxiety disorders were combined and sequenced with the onset and ending of sexual abuse. Hazard rates were calculated. Departures from the overall linear hazard trajectory for onsets were modeled using piecewise growth curve analyses. Increases from the overall trajectory were found around the point of sexual abuse onset for most childhood anxiety disorders. Decreases were found around the ending of sexual abuse. The risk for developing new anxiety disorders after the onset of sexual abuse showed a positive dose-effect relation with abuse severity. The findings add support to the idea that CSA can have a direct link to childhood anxiety disorders, apart from confounded vulnerability factors, postabuse events, or stable family background factors. The findings are contrasted with those from cross-sectional partial correlation studies that have suggested that there is little direct connection between sexual abuse and mental health outcomes.  相似文献   
2.
Subsequent to an initial understanding that estrogen was only stimulatory to folliculogenesis, we have come full circle to the present recognition that many actions of estrogen are inhibitory to follicular function. The development of this interpretation has frequently been associated with the controversial issue o f the likely site o f estrogen action, especially in primates, where much of the evidence has been amassed. The accumulated findings in a variety of species seem to demonstrate clearly that at least part of the atretogenic effect of estrogen is exerted directly on the ovary, apparently by interaction with the nuclear estrogen receptor. Recent observations include identification of messenger RNAs for the estrogen receptor and for creatine kinase in the macaque ovary, and a current focus is to localize messages within specific compartments of the ovary.  相似文献   
3.
Using polyclonal antibodies (PAbs) raised against the Candida albicans C3d receptor (CR2; PAb anti-CR2) and the 58-kDa fibrinogen-binding mannoprotein (mp58; PAb anti-mp58) as well as ligand interactions, we have studied the relationship between these two receptors. In an indirect immunofluorescence assay with germ tubes, greater intensity was observed on the mother blastoconidium when PAb anti-CR2 was used, whereas greater intensity was localized to the hyphal extension when PAb anti-mp58 or binding of soluble fibrinogen was used. No competition or change in the fluorescence pattern was observed in dual-labeling experiments with PAb anti-CR2 and either fibrinogen or PAb anti-mp58. Binding competition also was not observed in an enzyme-linked immunosorbent assay using the components present in a beta-mercaptoethanol extract from the cell wall of germ tubes. In immunoblots, PAb anti-CR2 recognized three different discrete bands with apparent molecular masses of 21, 40, and 66 kDa in the beta-mercaptoethanol extracts from the cell wall, whereas a different, single, broader band with an apparent molecular mass of 58 kDa was detected with PAb anti-mp58. However, when nondenaturing conditions were used to separate the materials present in the cell wall extracts, no reactivity could be detected on Western blots (immunoblots) with PAb anti-mp58. When PAb anti-CR2 was used for analysis, a single band migrating in the area corresponding to approximately 40 kDa was detected. These observations suggest a higher molecular weight for mp58 and one or more of the components detected with PAb anti-CR2 in their native state.  相似文献   
4.
进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关  相似文献   
5.
Hydrolysis of peptides within lumen of small intestine   总被引:2,自引:0,他引:2  
  相似文献   
6.
The surface expression of an antigenic determinant that is present in the cell wall of Candida albicans was investigated with monoclonal antibody 24 (MAb24), an immunoglobulin M MAb. The proportion of the cell population that expressed the epitope under different growing conditions was determined by indirect immunofluorescence microscopy. More than 90% of stationary-phase yeast cells of strain B311 grown at 28 degrees C expressed the antigen. Less than 50% of yeast cells grown exponentially at 28 degrees C or either growing or stationary-phase yeast cells cultivated at 37 degrees C expressed the epitope. Germ tubes, which were induced at 37 degrees C from stationary-phase yeast cells grown at 28 degrees C, expressed the determinant on the parent yeast but not the hyphal portion of the germ tube. The change in antigen expression by stationary-phase cells grown at 28 degrees C, when they resumed growth by bud formation, suggested that antigen expression was lost by cells in the inoculum prior to the first cell division. By using the same assay, strong positive reactions were observed in stationary-phase cultures of other isolates of C. albicans, C. guilliermondii, C. stellatoidea, and C. tropicalis, but not with isolates of C. krusei, C. parapsilosis, or Torulopsis glabrata. The identification of the antigenic determinant as a carbohydrate was based on three observations: (i) interaction with a mannan preparation from the same organism, (ii) sensitivity of the antigen to periodate but not proteases, and (iii) coincidence of the migration of antigen during electrophoresis with material which stained intensely with carbohydrate but not with protein reagents. These observations suggest that the expression of the antigenic determinant of MAb24 is dependent on the growth conditions, growth state, and morphology of the cell and that the topography of the cell surface is dynamic.  相似文献   
7.
An ex vivo adhesion assay was used to examine the binding of Candida albicans yeast cells to tissues from mice treated with cytotoxic drugs such as lipopolysaccharide and the clinically used anticancer drugs doxorubicin, cisplatin, and vincristine. No major differences were observed in binding of the fungal cells to liver and kidney tissues from treated or untreated animals. All drug-treated spleens displayed altered patterns of C. albicans adhesion compared with the control group, with yeast cells bound not only to the marginal zone but also to the white and red pulp. Immunostaining for macrophages, which are proposed as the site of normal adhesion, showed no apparent differences between the control and the experimental spleens that could account for the change in adhesion patterns. Scanning electron microscopy images suggested that yeast binding to the white pulp of treated tissue is mediated through fibers, perhaps extracellular matrix components exposed as result of the cytotoxic treatment. Exposure of new attachment sites for C. albicans in treated tissues may facilitate initiation of infection.  相似文献   
8.
Summary The relationships of VII and VIII cranial nerves and related arteries are reviewed in 26 preparations by microdissection techniques. These vessels may be grouped in large (AICA, PICA), medium (LA, SA, CSA, RPI) and small calibre (vasa nervorum, radicullar and medullar branches). The importance of these structures in acoustic neuroma surgery, vestibular neurectomy and cross-compression syndromes is discussed. Vascular loops and elongated arteries are normal structures present at birth.This work was supported by a grant from the AJ Roemmers Foundation  相似文献   
9.
Differential pattern of DNA-aneuploidy in human malignancies   总被引:5,自引:0,他引:5  
The differential pattern of DNA-aneuploidy, detected by flow cytometry (FCM) regarding its frequency, grade and multiclonality, was investigated and correlated to tumor type, malignancy grade, tumor stage and prognosis in a multi-institutional study at the University of Münster. High resolution measurements using admixed normal blood reference cells were undertaken in 2413 cases of 13 different malignant diseases and in 776 benign lesions or samples. The incidence of DNA-aneuploidy was highest in melanomas, carcinomas, testicular tumors, sarcomas (75%-95%) and myelomas (65%). Acute leukemias showed an intermediate DNA-aneuploidy rate of 40% with special subgroups represented by common ALL (44%), p less than 0.05) and myelomonocytic/monocytic AML (47%, p less than 0.01). The lowest DNA-aneuploidy-rate was found in basal cell skin carcinomas (19%) and congenital melanocytic nevi (9%). No case of DNA-aneuploidy was observed in the 776 benign lesions or samples.--DNA-indices giving the grade of DNA-aneuploidy with 1.0 for normal diploid G1/0 cells were found distributed predominantly between 1.0 and 2.0 in the solid tumors, except testicular tumors, clustering around a triploid maximum at 1.5. DNA-indices of myelomas and acute leukemias generally ranged below 1.25 with lower DNA-aneuploidy grades in AML than in ALL (p less than 0.01).--In melanomas the aneuploidy rate was higher (86%) in metastases than in the primary tumors (54%, p = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
10.
Hemmelgarn, Glisson, and James (2006) provide an excellent review of the impact of organizational culture and climate for the implementation of evidence-based practice (EBP) models within social and mental health services systems. As their article makes clear, the implementation process should address the organizational context, and effectiveness and services research should consider organizational factors in outcome and EBP transport research. This commentary extends discussion of one aspect of organizational culture—the extent to which organizations are driven by an empirical scientific epistemology—and how this may contribute to establishing a context for EBP design, selection, implementation, and sustained evolution in field settings.  相似文献   
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