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31.
Adult mongrel dogs were castrated and treated by intramuscular injections of 5 alpha-androstane-3 alpha,17 beta-diol (androstanediol) alone or in combination with estradiol in order to find convenient enzymatic markers of hormone action in prostate. The activities of 15 hydrolytic enzymes were determined. Arginine esterase, acid sulfatase, and acid phosphatase were found to be the most sensitive markers of testicular hormones since they were decreased 18-, 5- and 5-fold respectively after 1 month of castration. The enzyme activities returned to precastration levels after 2 weeks of injection of androstanediol to castrated animals. The effect of androstanediol on the majority of the remaining enzymes was small. In general, the activities obtained after androstanediol treatment in combination with estradiol were similar to those obtained with androstanediol alone. Finally, beta-glucuronidase and neutral sulfatase were increased after castration, a finding that suggests that these enzymes are constituents of stromal cells. These studies will provide a basis for future studies of hormone action in the dog prostate. 相似文献
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RR Pfister 《Canadian Metallurgical Quarterly》1983,90(6):601-609
Chemical burns of the eye may destroy all of the corneal epithelium and large portions of conjunctival epithelium into the fornices. Restoration of the ocular surface after a chemical burn depends on the centritedal movement of conjunctival epithelial cells and their adherence to the altered corneal stroma. Epithelial movement after a corneal burn is normal for 72 hours after a burn, but persistent epithelial defects thereafter commonly are not resolved until total corneal vascularization occurs. Although this fresh epithelium may be protected by a bandage soft contact lens, more promising and far-reaching approaches may follow epithelial supplementation and even replacement. The link between the health and integrity of the epithelial layer as it relates to the corneal substratum and its cellular constituents remains to be forged. 相似文献
33.
Two hundred twenty-five adolescent offenders completed the Stages of Change Scales (SOCS), which were designed to measure 4 stages of psychological and behavioral change. The goals of this research were to obtain norms among adolescent offenders for the SOCS, to examine the factor structure of the SOCS, and to investigate the convergent and discriminant validity of the SOCS by examining associations among these scales and the Paulhus Deception Scales (PDS; D. L. Paulhus, 1994, 1999) and Multidimensional Anger Inventory (MAI; J. M. Siegel, 1986). Means and alpha coefficients for the SOCS were similar to those reported in a previous normative clinical sample of adult patients. However, relatively large intercorrelations among the 4 scales of the SOCS, and results from factor analyses of SOCS items, suggested that fewer than 4 factors represented the SOCS items among the sample of adolescent offenders. Patterns of correlations with the PDS and with the MAI provided convergent and discriminant validity for the SOCS. Implications of the findings for research and clinical practice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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S Cascinu R Labianca P Alessandroni M Marcellini RR Silva G Pancera E Testa G Martignoni S Barni L Frontini A Zaniboni G Luporini R Cellerino G Catalano 《Canadian Metallurgical Quarterly》1997,15(11):3313-3319
PURPOSE: A multiinstitutional trial was performed to confirm the clinical activity, in terms of response rate and toxicity (primary objectives) and duration of responses and survival (secondary objectives), of an intensive weekly regimen in advanced gastric cancer. PATIENTS AND METHODS: Patients with measurable unresectable and/or metastatic gastric carcinoma received 1-day per week administration of cisplatin (CDDP) 40 mg/m2, fluorouracil (5FU) 500 mg/m2, epi-doxorubicin (epi-ADR) 35 mg/m2, 6S-stereoisomer of leucovorin 250 mg/m2, and glutathione 1.5 g/m2. On the other days, filgrastim was administered by subcutaneous injection at a dose of 5 mg/kg. One cycle of therapy consisted of eight 1-week treatments. Patients who showed a response or stable disease received a further 6 weeks of therapy. RESULTS: Of 105 enrolled patients, 11 had locally advanced unresectable disease only; 33 had primary nonresected and metastatic disease; 48 had metastatic disease and primary tumor resected; 10 had locoregional recurrence and metastatic disease; and three had locoregional recurrence only. After one cycle, 18 complete responses (CRs) and 47 partial responses (PRs) were achieved, for an overall response rate of 62% (95% confidence interval [CI], 53% to 71%). Twenty patients had stable disease and 20 progressed on therapy. The median survival duration of all 105 patients was 11 months, with 1- and 2-year survival rates of 42% and 5%, respectively. World Health Organization (WHO) grade III to IV toxicity, in terms of anemia, neutropenia, thrombocytopenia, and mucositis, was experienced by 40 patients (38%). There were no treatment-related deaths. CONCLUSION: These data support the results of the pilot study and confirmed the high activity of the regimen, with acceptable toxicity. This schedule deserves evaluation in the adjuvant setting. 相似文献
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R. W. Hemphill 《Journal of the American Ceramic Society》1925,8(3):145-147
Some effects of foreign matter, dampness, ball clay content, sponging, dust and drying are shown on pinholing in cast ware. 相似文献
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Social behaviors of most mammals are profoundly affected by chemical signals, pheromones, exchanged between conspecifics. Pheromones interact with dendritic microvilli of bipolar neurons in the vomeronasal organ (VNO). To investigate vomeronasal signal transduction pathways, microvillar membranes from porcine VNO were prepared. Incubation of such membranes from prepubertal females with boar seminal fluid or urine results in an increase in production of inositol-(1, 4, 5)-trisphosphate (IP3). The dose response for IP3 production is biphasic with a GTP-dependent component at low stimulus concentrations and a nonspecific increase in IP3 at higher stimulus concentrations. The GTP-dependent stimulation is mimicked by GTPgammaS and blocked by GDPbetaS. Furthermore, the GTP-dependent component of the stimulation of IP3 production is sex specific and tissue dependent. Studies with monospecific antibodies reveal a G alpha(q/11)-related protein in vomeronasal neurons, concentrated at their microvilli. Our observations indicate that pheromones in boar secretions act on vomeronasal neurons in the female VNO via a receptor mediated, G protein-dependent increase in IP3. These observations set the stage for further investigations on the regulation of stimulus-excitation coupling in vomeronasal neurons. The pheromone-induced IP3 response also provides an assay for future purification of mammalian reproductive pheromones. 相似文献
40.
In this paper we report the results of both an experimental and theoretical study of the halfwidths of two transitions of water vapor. Measurements on the lines of the H216O and H218O isotopomers located at 325.1 and 203.4 GHz, respectively, were carried out in the temperature range 300-393 K, with N2 and O2 as perturbing gases. The foreign-broadening coefficients and their temperature-dependence parameters were determined assuming a Voigt profile and the usual temperature dependence for the halfwidth. The retrieved values are compared to values calculated using the complex semiclassical formalism of Robert and Bonamy. The assumed intermolecular potential is a combination of electrostatic and atom-atom components. This last contribution is defined as the sum of pairwise Lennard-Jones 6-12 interactions between the atoms of H2O and the atoms of the perturbing molecules expanded to eighth order. Also calculated are the pressure-induced shifts of the spectral lines for temperatures from 200 to 400 K. Calculated and experimental results are in good agreement, within +/-3.2%, except for the N2-broadening temperature coefficients, for which there are discrepancies as high as 23%. Air-broadening parameters are determined following the classical relation: gamma (air) = 0.79gamma (N2) + 0.21gamma (O2). Copyright 1999 Academic Press. 相似文献