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71.
"Suspicious" gynecologic smears from 842 patients over a seven-year period were analyzed for their causes and outcomes. The frequency of the cytologic diagnosis of "suspicious" ranged between 0.5% in 1979 and 1.44% in 1975 of all smears examined. Review of the smears showed that this classification was used to report a variety of conditions, including equivocal possible precancerous changes as well as the presence of severe inflammation, degenerative or atrophic changes, abnormal glandular cells and metaplasia. The cytologic follow-up, following anti-inflammatory or hormonal therapy, showed a conversion to negative findings in 65.1% of all cases, usually within 12 months. In 294 cases, histologic analysis became necessary, revealing precancerous changes or cancer in 147 patients (17.5% of the study group). Smears of postmenopausal women with suspicious glandular or endometrial cells received special analysis. Significant numbers of such cases had histologic findings positive for malignancy (20% of smears with glandular cells and 21.3% with endometrial cells), as did also smears showing post-irradiative changes (34.6%) or atrophic and degenerative changes (17.1%). Therefore, "suspicious" smears in these groups were considered to indicate an increased risk of malignancy. A regimen for the proper management of cases with "suspicious" smears has been established. 相似文献
72.
12 beta-dehydrogenation of bile acids by Clostridium paraputrificum, C. tertium, and C. difficile and epimerization at carbon-12 of deoxycholic acid by cocultivation with 12 alpha-dehydrogenating Eubacterium lentum. 总被引:1,自引:1,他引:0 下载免费PDF全文
12 beta-Hydroxysteroid dehydrogenating activities were detected in 13 strains of Clostridium paraputrificum, 1 strain of C. tertium, and 1 strain of C. difficile, together with a 3 alpha- and 3 beta-hydroxysteroid dehydrogenase system in many strains. Redox reactions a C-12 of disubstituted and trisubstituted bile acids were performed unspecifically by representative strains of C. paraputrificum. 3 alpha,12 beta-, 3 beta,12 beta-Dihydroxy-, 3 alpha, 7 alpha, 12 beta-trihydroxy-, and 3-keto,12 beta-hydroxy-5 beta-cholanoic acids, so far not known as bacterial bile acid metabolites, were identified. Epimerization of the 12 alpha-hydroxyl group of deoxycholate via the 12-keto intermediate was achieved by cocultivation of C. paraputrificum and Eubacterium lentum, elaborating a 12 alpha-hydroxysteroid dehydrogenase only. In addition, epimerization at C-12 was demonstrated with mixed human fecal cultures. 相似文献
73.
A mos oncogene-containing retrovirus, myeloproliferative sarcoma virus, transforms rat thyroid epithelial cells and irreversibly blocks their differentiation pattern. 总被引:8,自引:1,他引:7 下载免费PDF全文
A Fusco G Portella P P Di Fiore M T Berlingieri R Di Lauro A B Schneider G Vecchio 《Journal of virology》1985,56(1):284-292
74.
12 beta-Hydroxysteroid dehydrogenating activities were detected in 13 strains of Clostridium paraputrificum, 1 strain of C. tertium, and 1 strain of C. difficile, together with a 3 alpha- and 3 beta-hydroxysteroid dehydrogenase system in many strains. Redox reactions a C-12 of disubstituted and trisubstituted bile acids were performed unspecifically by representative strains of C. paraputrificum. 3 alpha,12 beta-, 3 beta,12 beta-Dihydroxy-, 3 alpha, 7 alpha, 12 beta-trihydroxy-, and 3-keto,12 beta-hydroxy-5 beta-cholanoic acids, so far not known as bacterial bile acid metabolites, were identified. Epimerization of the 12 alpha-hydroxyl group of deoxycholate via the 12-keto intermediate was achieved by cocultivation of C. paraputrificum and Eubacterium lentum, elaborating a 12 alpha-hydroxysteroid dehydrogenase only. In addition, epimerization at C-12 was demonstrated with mixed human fecal cultures. 相似文献
75.
Henry Schneider George Mahmourides John L. Labelle Hung Lee Nancy Maki Heather J. McNeill 《Biotechnology letters》1985,7(5):361-364
The formation of ethanol, xylitol, ribitol, arabitol and acetic acid from D-xylose byPachysolen
tannophilus correlated with the limitation of growth. The correlation was consistent with these products being secondary metabolites.Issued as NRCC Publication Number 24259. 相似文献
76.
White D. P.; Schneider B. K.; Santen R. J.; McDermott M.; Pickett C. K.; Zwillich C. W.; Weil J. V. 《Journal of applied physiology》1985,59(5):1452-1457
There is increasing evidence that men have higher ventilatory responses to chemical stimuli than age-matched women and that certain disorders of respiratory rhythmicity, particularly sleep apnea, occur more commonly in men. Accordingly, we studied the influence of the male hormone, testosterone, on the control of breathing. Twelve hypogonadal males were studied at least 30 (mean +/- SE: 69.7 +/- 8.9) days after discontinuing testosterone replacement and again following hormone administration. In each subject plasma testosterone concentration, metabolic rate [O2 consumption (VO2) and CO2 production (VCO2)], minute ventilation (VE), and chemosensitivity [hypoxic (HVR) and hypercapnic (HCVR) ventilatory responses] were determined on and off hormone replacement. With testosterone administration VO2 increased from 248 +/- 15 to 276 +/- 18 ml/min (P less than 0.05), with VCO2 showing a similar but nonsignificant trend. This was associated with an increase in VE from 8.41 +/- 0.78 to 9.91 +/- 0.75 l/min (P less than 0.05) but no change in PCO2. The HVR, expressed as A, increased 44% with hormone replacement from a value of 122 +/- 23 to 176 +/- 28 (P less than 0.01), whereas the HCVR was minimally affected by testosterone administration. These findings may in part explain the previously described differences between male and female subjects in hypoxic sensitivity. 相似文献
77.
Inhibitory effects of somatostatin on growth and differentiation in cultured intestinal mucosa 总被引:1,自引:0,他引:1
The effect of somatostatin on mucosal DNA, protein and brush border enzymes was studied in organ cultured rabbit jejunum and ileum. Compared to control cultures, somatostatin reduced the biopsy DNA and protein content in parallel in the jejunum, but was ineffective in the ileum. This was probably due to a direct growth inhibition, since DNA and brush border enzyme activity from desquamated cells in the postculture medium were unaffected. In addition, a direct inhibition of jejunal villous cell differentiation by somatostatin was reflected in a significant decrease of sucrase, maltase and alkaline phosphatase activity. In the ileum, only the specific activity of alkaline phosphatase was reduced. The key enzyme of cholesterol synthesis, HMG-CoA-reductase, was measured as an intracellular enzyme control and was not influenced by the hormone. The high somatostatin concentrations necessary to achieve the effects are not an artefact of hormone degradation during culture, as shown by radioimmunoassay, and suggest a local or "paracrine" rather than systemic, inhibitory action of somatostatin on intestinal growth and differentiation. 相似文献
78.
A novel type of human T cell clone with highly potent natural killer-like cytotoxicity divorced from large granular lymphocyte morphology 总被引:1,自引:0,他引:1
E M Schneider G P Pawelec S Liangru P Wernet 《Journal of immunology (Baltimore, Md. : 1950)》1984,133(1):173-179
Interleukin 2-dependent cloned lymphocytes derived from an allogeneic HLA class II-mismatched but class I-matched mixed lymphocyte culture were screened for cytotoxic activity on target cell lines known to be susceptible or resistant to lysis by natural killer (NK) cells. Of 24 clones, eight were found to display NK-like cytotoxicity. Two manifested extremely high cytotoxicity levels (50% lysis of K562 at an effector to target ratio of 1:1), whereas the remainder were only moderately active (about 20% lysis at 25:1). NK-like clones were studied with regard to cell surface markers defined by monoclonal antibodies, as well as for their morphologic and cytochemical characteristics, and were compared with clones displaying different functions. The moderately active NK-like clones exhibited characteristic large granular lymphocyte morphology (many azurophilic granules, indented nuclei, high cytoplasm to nucleus ratio, and a basophilic peripheral cytoplasmic zone). This was, however, also characteristic of the majority of lymphocyte clones displaying functions other than NK. Surprisingly, the two clones with high NK-like activity did not exhibit large granular lymphocyte morphology, with few granules, round nuclei, and low cytoplasm to nucleus ratio. The T3, T9, T10, and T11 markers, as well as HLA-DR determinants, were expressed on their surfaces, but in contrast to the other clones, they did not display OKT4-, OKT8-, or OKM1-defined antigens. No distinction between them was possible on the basis of a cytochemical profile in relation to their function, because all clones were positive for acid phosphatase, either focal or dispersed and negative for nonspecific esterase or chloracetate esterase. The highly active lytic clones were, however, distinguished by an exceptionally rapid growth rate in culture (cell doubling time: 9 hr as compared to 30 to 40 hr, as usually required). These results demonstrate two different types of human NK-active lymphocytes with remarkably disparate lytic capacity, cell surface markers, and morphology. 相似文献
79.
Adenovirus VAI RNA antagonizes the antiviral action of interferon by preventing activation of the interferon-induced eIF-2 alpha kinase 总被引:64,自引:0,他引:64
J Kitajewski R J Schneider B Safer S M Munemitsu C E Samuel B Thimmappaya T Shenk 《Cell》1986,45(2):195-200
The VAI RNA of adenovirus is a small, RNA polymerase III-transcribed species required for efficient translation of host cell and viral mRNAs late after infection. The growth of a viral mutant that is unable to produce the RNA is inhibited by interferon, while wild-type virus is not affected. VAI RNA prevents activation of the interferon-induced P1/eIF-2 alpha kinase. This inhibition can be reproduced in extracts of interferon-treated cells where purified VAI RNA prevents activation of latent kinase by double-stranded RNA. 相似文献
80.
Lee H James AP Zahab DM Mahmourides G Maleszka R Schneider H 《Applied and environmental microbiology》1986,51(6):1252-1258
The conversion of d-xylose to ethanol by the yeast Pachysolen tannophilus is relatively inefficient in batch culture. The inefficiency has been attributed in part to concurrent utilization of ethanol in the presence of appreciable concentrations of d-xylose and to the formation of xylitol and other by-products. To increase the concentration of ethanol accumulated in batch cultures, UV-induced mutants of P. tannophilus were selected on the basis of diminished growth on ethanol. Eleven independent mutant loci that conferred the ethanol-defective phenotype were identified. Three led to a greater yield and volumetric rate of production of ethanol than the wild type. One also produced less xylitol and was characterized by a deficiency in activity for malate dehydrogenase. 相似文献