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DNA measurement by flow cytometry has been demonstrated to be a potentially useful technic in the diagnosis of bladder cancer by detecting neoplastic cells in bladder washings and urine specimens. The authors' goal was to develop a simple and practical method utilizing the new generation of cytofluorographs designed for use in the clinical laboratory. This method combined direct fixation with cell lysis yielding fixed intact nuclei. Following RNase and pepsin digestion, the nuclei were separated from debris and aggregates on a sucrose barrier, stained with ethidium bromide, and analyzed with an argon laser analytic cytofluorograph. Urines and bladder washings from 14 patients with positive urinary cytology and histologically diagnosed bladder cancers were compared with specimens from patients without urothelial malignancies. DNA histograms clearly delineated aneuploid from diploid populations and often identified S, G2M, and G1 phase nuclei. Aneuploid populations have been detected in all tumor specimens with positive cytologies studied to date.  相似文献   
75.
Murine anti-reovirus cytotoxic T lymphocytes (CTLs) were analyzed for H-2 restricted recognition of virus infected target cells and for potential cross-reactivity with cells infected by reovirus serotype 1 (T1; Lang strain) or by serotype 3 (T3; Dearing strain). Anti-reovirus CTL specifically lysed virus infected cells and lysis was shown to be H-2 restricted by the H-2Dd, H-2Ld, H-2Kd, H-2Kb, and H-2Kk antigens. No H-2 antigens were identified which failed to restrict virus recognition by anti-reovirus CTL. Anti-T1 and anti-T3 CTLs were also shown to crossreact completely with cells infected with the opposite virus serotype. Thus, anti-reovirus CTLs are restricted by a broad spectrum of H-2 antigens and they detect common rather than unique structural components of these two viral serotypes.  相似文献   
76.
Adverse effects of wound healing, such as excessive scar tissue formation, wound contraction, or nonhealing wounds represent a major clinical issue in today's healthcare. Transforming growth factor (TGF)-beta3 has specifically been implicated in wound healing. Our hypothesis was that local administration of TGF-beta3 to excisional dermal wounds would diminish wound contraction and scar formation. Microtextured wound covers, containing different concentrations of TGF-beta3, were placed onto full-thickness excisional skin wounds in guinea pigs. Tattooed reference marks were used to quantify wound contraction. Sixty-four male guinea pigs in four study groups (5 ng TGF-beta3, 50 ng TGF-beta3, no growth factor, sham wound) were followed for up to 6 weeks. We analyzed 19 different parameters of wound healing. Results showed that, in some instances, the 50-ng TGF-beta3 group gave less contraction, whereas the 5-ng TGF-beta3 group gave more contraction. These differences confirm that TGF-beta3 has an optimum working concentration, and suggest this concentration to be closer to 50 ng than to 5 ng TGF-beta3. However, only very few significant differences occurred, and thus we conclude that the clinical relevance of our findings is negligible. Earlier studies, reporting clinically improved wound healing by TGF-beta3, could therefore not be confirmed by this study.  相似文献   
77.
The incidence of HL-A antigens in patients having a variety of medical conditions, but sharing the common feature of a positive antiglobulin test of the red cells, was determined. There was a significant increase in the antigens HL-A 1 and HL-A 8 and of the 1 and 8 combination when compared with a control group. It is suggested that the presence of these antigens may predispose to autoallergy.  相似文献   
78.
BACKGROUND: Pathological gambling is more prevalent among postsecondary students than among the general adult population. While the prevalence of pathological gambling in this group has risen over the past decade, factors underlying the development of problem gambling among university students remain largely unexplored. One early study found alexithymia to be associated with pathological gambling. The aim of the present study was to further examine the relationship between alexithymia and gambling among postsecondary students. METHODS: The relationship between alexithymia and pathological gambling was examined in 562 postsecondary students who completed the South Oaks Gambling Screen (SOGS) and the 20-item Toronto Alexithymia Scale (TAS-20). RESULTS: Approximately 12% of the sample was classified as alexithymic according to the TAS-20. These individuals were found to have significantly more gambling problems, as measured by the SOGS, than nonalexithymic individuals. Approximately 9% of the sample was classified as pathological gamblers according to the SOGS. These individuals were found to have significantly higher levels of alexithymia, as measured by the TAS-20, than nonproblem gamblers. CONCLUSIONS: Alexithymia is associated with pathological gambling and may be a risk factor among postsecondary students for developing severe gambling problems.  相似文献   
79.
Addressing certain problems with the compositional structure of the self-report Toronto Alexithymia Scale, this paper reports the development of a revised version of the scale as well as results from a preliminary series of studies evaluating its reliability and validity. The Revised Toronto Alexithymia Scale (TAS-R) demonstrated good internal consistency and a stable and replicable two-factor structure that is congruent with the two major dimensions of the alexithymia construct. Evidence of convergent and discriminant validity for the TAS-R was provided by correlations with measures of other constructs. Criterion validity was demonstrated by the ability of TAS-R scores to discriminate between behavioral medicine outpatients designated alexithymic and those designated non-alexithymic on the basis of clinical interview ratings. Normative data are provided for university student, normal adult, and psychiatric outpatient populations.  相似文献   
80.
The endothelial cell (EC) -specific secreted protein EGFL7 is important for tubulogenesis in newly forming blood vessels. We studied its role in vascular tube formation by a quantitative ultrastructural analysis of Egfl7-knockdown zebrafish embryos. At 24 hours postfertilization, the endothelia of dorsal aorta (DA) and posterior cardinal vein (PCV) were correctly anchored to the hypochord and endoderm, respectively, but failed to expand into the vascular area. This resulted in vessels with reduced or split lumen and open sheets of ECs. Concomitantly, the organization of hematopoietic cells-identified by the presence of previously undescribed membrane tubules-between DA and PCV, and within the vessels, was severely disturbed. Strikingly, ectopic cell junctions occurred across the obstructed vessel lumen, on the luminal EC surfaces, which in control conditions never display junctions of any kind. These data suggest that Egfl7 provides ECs with a cue for their extension into the vascular area and in establishing EC cell polarity.  相似文献   
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