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941.
942.
943.
The prognostic significance of tumour cell proliferation was investigated in a series of 418 gastric carcinomas using the monoclonal antibody MIB-1. Owing to strong intratumoural heterogeneity of MIB-1 expression three different proliferation indices (PIs) were determined in all carcinomas: (1) PImax in areas of maximal tumour cell proliferation, (2) PIrand in areas randomly distributed over the whole tumour. (3) PIfront in areas exclusively located at the tumour invasion front. There was a strong intertumoral heterogeneity with PImax ranging from 4.9% to 92.2%, PIrand ranging from 3.4% to 81.4% and PIfront ranging from 4.2% to 87.1%. The mean values were 51.3% +/- 19.7 for PImax, 34.2% +/- 18.3 for PIrand and 37.2% +/- 19.5 for PIfront. Whereas no statistically significant correlation could be found between proliferative activity and the clinicopathological parameters depth of invasion, lymph node involvement or grade of tumour differentiation, there was a positive correlation between a high proliferation index at the tumour invasion front (PIfront) and the presence of blood or lymphatic vessel invasion. No significant correlation could be demonstrated between the different proliferation indices and survival, even when different subgroups of patients were analysed separately. The present results suggest that the immunohistochemical evaluation of the proliferation activity has no predictive value for the prognosis of gastric cancer patients or the identification of subgroups of patients who may be at higher risk. 相似文献
944.
RG Twycross 《Canadian Metallurgical Quarterly》1996,89(2):61-63
From 1970 to 1990 the authors treated 4 patients with deep colitis (DCC). There were 2 males and 2 females aged from 19 to 48 years (average age 28.7 years). A local form of DCC with involvement of the rectum (infero- and preampullar part) was recognized in all cases. The only method for DCC treatment is an operative intervention whose volume is determined by the form of the disease and the results of emergency intraoperative morphological study of the affected parts of the large intestine. All 4 patients underwent organ- and sphincter-preserving operation-transanal resection of the rectum. The postoperative period was uneventful. None of the patients had a recurrence of the disease in follow-up periods of 3 to 7 years. 相似文献
945.
The purpose of this study was to compare the clinical results of guided periodontal tissue regeneration (GPTR) using a resorbable barrier manufactured from a copolymer of polylactic and polyglycolic acids (Resolut Regenerative Material) with those of non-resorbable e-PTFE barrier (Gore-Tex Periodontal Material). 12 subjects participated, 6 with similarly paired class II furcations and 6 with 2 similar 2, 3-wall periodontal lesions. The resorbable and non-resorbable barriers were randomly assigned to 1 defect in each subject. Non-resorbable barriers were removed in six weeks. Plaque index (PlI), gingival index (GI), probing depth (PD), clinical attachment level (CAL) and gingival recession (R) were recorded at baseline, (i.e., immediately prior to surgery) and at 12 months postsurgically. The clinical healing was similar and uneventful in both groups. Intrabony pockets depicted significant changes from baseline (p < 0.05) for probing depth reduction and gain in clinical attachment levels. No differences were found between treatments. Class II furcations showed significant improvements from baseline (p < or = 0.05) for probing depth reduction and clinical attachment gain. No differences were detected between treatments. It is concluded that the resorbable barrier tested is as effective as the nonresorbable e-PTFE barrier for the treatment of class II furcations and intrabony defects. 相似文献
946.
RG Kozhedub 《Canadian Metallurgical Quarterly》1997,47(5):870-877
The universal principle of brain operation which consists in initial global non-specific reactions and secondary local specific changes is reflected at the behavioral level in the dominant properties of the generalization stage of conditioned reflex and its transition to the specialization stage. These phenomena correspond at the cellular level to a temporary increase in excitability of cortical neurons and long-term modifications of synaptic efficacy in interneuronal excitatory and inhibitory connections. Such a sequence of events is largely determined by the dynamics of hypothalamic-cortical integration and operation of N-methyl-D-aspartate (NMDA) receptor-channel complex. Increase in cell excitability which results at the initial stage of learning in a transition of cells to burst discharge mode of unit activity and is accompanied by pronounced generalized synchronization of slow electrical activity in the theta-rhythm range promotes manifestation of synaptic modifications, which, in turn, determine a specialized conditioned motor act at the terminal stage. 相似文献
947.
OBJECTIVE: The objective of this study was to determine the predictors of future ambulatory blood pressure in normotensive youths with family histories of essential hypertension. STUDY DESIGN: Eighty-eight healthy youths (mean age 10.9 +/- 2.5 years; 52 blacks, 36 whites; 45 boys) were studied. During an initial visit anthropometric variables and hemodynamics were measured at rest and before, during, and after three laboratory stressors: postural change, forehead cold, and video game challenge. The subjects' ambulatory blood pressure was monitored for 24 hours as part of a follow-up evaluation an average of 2.5 years later. RESULTS: Anthropometric and demographic variables and measures of reactivity to laboratory stressors were related to future daytime and nighttime ambulatory blood pressure. CONCLUSION: These findings provide important information on the predictors of ambulatory blood pressure and underscore the importance of resting blood pressure and adiposity. These results support the guidelines of the Second Task Force, which recommend the measurement of blood pressure and adiposity in the context of ongoing health care. 相似文献
948.
Cross-linking CD21/CD35 or CD19 increases both B7-1 and B7-2 expression on murine splenic B cells 总被引:1,自引:0,他引:1
Y Kozono R Abe H Kozono RG Kelly T Azuma VM Holers 《Canadian Metallurgical Quarterly》1998,160(4):1565-1572
Activation of the complement cascade and ligation of complement C3 receptors on B cells represent an important bridge between innate and Ag-specific acquired immunity. We show here that cross-linking of mouse CD21 (complement receptor type 2, CR2, C3d receptor) and CD35 (complement receptor type 1, CR1, C3b/C4b receptor) or co-cross-linking of CD21/CD35 and surface IgM rapidly up-regulates both B7-1 and B7-2 expression on murine resting splenic B cells. CD21/CD35-mediated up-regulation of both B7-1 and B7-2 expression is observed within 14 h, while other stimuli up-regulate only B7-2 but not B7-1 at this early time point. Consistent with the increase in B7 levels, BALB/c B cells on which surface IgM and CD21/CD35 have been co-cross-linked stimulate C57BL/6 T cells more effectively than controls. This CD21/CD35-enhanced allogeneic MLR is blocked nearly completely by anti-B7-2 mAbs and partially by anti-B7-1 mAbs. In addition, cross-linking of CD19, which is physically associated with CD21/CD35, leads to increased B7-1 and B7-2 expression. These data suggest that CD21/CD35 ligation results in enhanced B cell Ag presentation using costimulatory mechanisms shared with other activators and thus works cooperatively in this process. Rapid up-regulation of B7-1 expression, a unique response to CD21/CD35 and CD19 cross-linking, may be a particularly important effect of C3-containing ligands. We propose that CD21/CD35- and CD19-mediated B7-1 and B7-2 up-regulation is an important mechanism by which complement activation links innate and acquired immunity. 相似文献
949.
950.
V Hwa C Tomasini-Sprenger AL Bermejo RG Rosenfeld SR Plymate 《Canadian Metallurgical Quarterly》1998,83(12):4355-4362
Insulin-like growth factor-binding protein-related protein-1 (IGFBP-rP1; also known as Mac25, TAF, and PSF) is a member of the IGFBP superfamily. It is a cysteine-rich protein that shares structural and functional similarities with the conventional IGFBPs. In situ hybridization of prostate tissue sections show intense IGFBP-rP1 messenger ribonucleic acid (mRNA) expression in normal stroma and glandular epithelium. There was a significant loss of detectable IGFBP-rP1 mRNA in metastatic prostate tissue. IGFBP-rP1 mRNA (Northern blots) and protein (immunoblots) were detectable in primary cultures ofprostatic stromal and epithelial cells as well as in the immortalized nonmalignant prostatic human epithelial cells, P69, and in the P69 metastatic subline, M12. IGFBP-rP1 expression was not detectable in the prostatic cancer cell lines PC-3, DU145, and LNCaP. IGFBP-rP1 expression was regulated in P69 cells but not in M12 cells. Protein and mRNA expression was up-regulated by IGF-I, transforming growth factor-beta, and retinoic acid. The observations that IGFBP-rP1 expression is significantly diminished in prostate tumorigenesis and is regulated in nonmalignant prostate cells suggest IGFBP-rP1 is important in normal prostatic cell growth. 相似文献