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191.
The study investigated the psychological health level and related psychosocial factors of nurses. Through cluster sampling, 650 clinical nurses, who come from 5 city hospitals in Changsha, were interviewed with the Symptom Check List-90 (SCL-90), The Life Event Scale, Type A Behavior Questionnaire, and The Social Support Rating Scale. The results indicated that subjects' average symptom score and most factor scores of SCL-90 were significantly higher than that of the chinese norm. Somatization, depression, and obsession are common psychological problems of the clinical nurses, and the psychological health level of middle age group was significantly lower than that of other groups. Regression analysis (both single factor and multiple factors) suggested that TH and CH scores on Type A Questionnaire as well as life event score on the life event score were negatively related to psychological health level while social support score was positively related to it. The influences of psychosocial factors on psychological health level of clinical nurses were discussed. 相似文献
192.
KH Kilburn 《Canadian Metallurgical Quarterly》1997,90(3):299-304
Our goal was to: 1) modify poly(vinyl alcohol) hydrogels intended for use in a synthetic cornea to absorb ultraviolet light and 2) develop molding procedures for the fabrication of the device. Two ultraviolet light-absorbing monomers were incorporated by copolymerization. The resulting hydrogels protected against ultraviolet light, were not toxic to corneal fibroblasts, and the protection did not diminish during prolonged aqueous exposure. A novel keratoprosthesis molding procedure was developed that made use of the phase transition properties of mixtures of poly(vinyl-trifluoroacetate) and acetonitrile. In this procedure the keratoprosthesis was shaped and a fibrous skirt was bonded to it in a single operation. Composite keratoprostheses were designed and prepared for in vivo testing. 相似文献
193.
As part of our investigation of structure-activity relationships in a Candida rugosa lipase-catalyzed ester hydrolysis reaction, methyl 2-(octylsulfinyl)benzoate has been studied, with respect to rate and enantioselectivity behaviour, using two different lipase preparations. A chiral normal-phase liquid chromatography method has been developed for determination of the experimental data, degree of conversion (c) and enantiomeric excess of the substrate (ees) or the product (eep), needed for calculation of the enantioselectivity in a kinetic resolution of this kind. A recently developed new class of network-polymeric chiral stationary phases, giving baseline-resolution with high selectivities for the ester substrates as well as their corresponding carboxylic acid products, permits, without any derivatization, an accurate and direct determination of the rate of the hydrolysis reaction and of the enantioselectivity from one and the same chromatogram. 相似文献
194.
We have compared the ex vivo antimalarial activity of 12 new quinoline di-Mannich base compounds containing the 7-dichloroquinoline or 7-trifluoromethylquinoline nucleus with amodiaquine, chloroquine, and pyronaridine using the Saimiri-bioassay model. Each compound was administered orally (30 mg/kg of body weight) to three or more noninfected Saimiri sciureus monkeys, and serum samples were collected at various times after drug administration and serially diluted with drug-free (control) serum. In vitro activity against the multidrug-resistant K1 isolate of Plasmodium falciparum was determined in serum samples by measuring the maximum inhibitory dilution at which the treated monkey serum inhibited schizont maturation in vitro. Of the 12 Mannich bases tested, 8 were associated with levels of ex vivo antimalarial activity in serum greater than those of amodiaquine, chloroquine, or pyronaridine 1 to 7 days after drug administration. Further studies were carried out with four of these compounds, and the results showed that the areas under the serum drug concentration-time curves for the four compounds were between 7- and 26-fold greater than that obtained for pyronaridine. Activity against four multidrug-resistant strains of P. falciparum was also much greater in serum samples collected from monkeys after administration of these four compounds than in serum samples collected after administration of pyronaridine or chloroquine. These findings suggest that these four quinoline Mannich base compounds possess a very marked and prolonged antimalarial activity and that further studies should be performed to determine their value as antimalarial drugs. 相似文献
195.
KH Abd-el-Maeboud 《Canadian Metallurgical Quarterly》1997,23(5):427-431
On laparoscopy in 3 patients with primary infertility, the only pathology found was hydatid cysts of Morgagni that were excised. In one patient with monolateral hydatid cyst, pregnancy failed to be achieved. Despite prior failure of repeated trials of ovulation induction and intrauterine insemination in the other 2 patients, a spontaneous pregnancy was achieved within 2-3 months following laparoscopic extirpation of hydatid cysts of Morgagni. The hydatid cysts were bilateral in one case; and monolateral (in relation to the only present tube with a unicornuate uterus) in the other case. It is concluded that hydatids of Morgagni, as a single pelvic pathology, might hinder fertility. Laparoscopic extirpation of these cysts would improve ovum pick-up and enhance fertility. 相似文献
196.
197.
R Ruckser P Kier C Sebesta E Kittl M Kurz S Selleny S H?niger M Scherz KH Habertheuer P Zelenka 《Canadian Metallurgical Quarterly》1995,145(2-3):41-4, 46-7
10 patients were subjected to tandem transplantation for breast cancer (n = 3), ovarian cancer (n = 2) and multiple myeloma (n = 5), at the Second Department of Medicine, Donauspital, Vienna. The breast cancer patients were in stages 2 and 3, respectively, at diagnosis and entered complete remission thereafter. 2 of them developed lymph node metastasis and additional local recurrence, the 3rd patient presented with distant metastasis. The 2 patients with ovarian cancer were in stages Figo III and IV, respectively, at the time of diagnosis, and showed minimal residual disease at second-look-operation. 5 patients with multiple myeloma were in stage 3 pretransplant. Peripheral stem cells were obtained after either high-dose cyclophosphamide or FEC induction and application of cytokines. In 4 patients, tandem transplantation has been completed. 1 patient with multiple myeloma, who had received total body irradiation in combination with chemotherapy for the 2nd transplant, succumbed from idiopathic interstitial pneumonia. No severe clinical complications were observed in all other patients. All patients with solid tumors entered complete remission after the 1st transplantation. 3 of them completed tandem transplantation. Of these, 2 remain in continuous complete remission, the 3rd patient relapsed in lymph nodes day 485. In patients who received only 1 course of high dose chemotherapy with stem cell transplantation, relapses occurred on days 29 and 75, respectively. All patients with multiple myeloma entered only partial remission. We conclude that supralethal chemotherapy with peripheral blood stem cell support is a safe procedure that may at least induce prolonged remissions in solid tumors and hematologic malignancies.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
198.
199.
SY Hong JE Oh M Kwon MJ Choi JH Lee BL Lee HM Moon KH Lee 《Canadian Metallurgical Quarterly》1998,42(10):2534-2541
Novel combinatorial libraries consisting of simplified amino acid sequences were designed to screen for peptides active against the Candida albicans membrane. A novel decapeptide, KKVVFKVKFK, that had a unique primary amino acid sequence was identified in this work. This peptide irreversibly inhibited the growth of C. albicans and showed a broad range of antibacterial activity but no hemolytic activity. Circular dichroism spectra revealed that the predominant secondary structure of this peptide strongly depended on the membrane-mimetic environments; the peptide preferred to form an amphipathic alpha-helical structure in the presence of 50% trifluoroethanol, while it preferred to adopt a distorted alpha-helical structure in the presence of sodium dodecyl sulfate micelles. Experiments in which dye was released from vesicles indicated that this novel antimicrobial peptide killed microorganisms through the action on the membrane as its primary target. Replacement of amino acids in this active decapeptide on the basis of information from the libraries could provide unique information about factors affecting its antimicrobial activity such as its secondary structure, net positive charge, and hydrophobicity. 相似文献
200.
U Krengel KH Schr?ter H Hoier A Arkema KH Kalk P Zimniak BW Dijkstra 《Canadian Metallurgical Quarterly》1998,422(3):285-290
STATEMENT OF PROBLEM: The electric alloy brazed joints of removable partial denture alloys have failed frequently after routine usage. PURPOSE: A technique providing higher joint strengths was investigated. This investigation compared the tensile strengths of electric-brazed and laser-welded joints for a cobalt-chromium removable partial denture alloy. MATERIAL AND METHODS: Twenty-four cobalt-chromium standard tensile testing rods were prepared and divided into three groups of eight. All specimens in the control group (group 1) were left in the as-cast condition. Groups 2 and 3 were the test specimens, which were sectioned at the center of the rod. Eight specimens were joined by using electric brazing, and the remaining specimens were joined by using laser welding. After joining, each joint was ground to a uniform diameter, then tested to tensile failure on an Instron universal testing machine. Failure loads were recorded and fracture stress calculated. Statistical analysis was applied. RESULTS: The student-Newman-Keuls test showed a highly significant difference between the joint strengths of the as-cast control specimens, the electric-brazed and laser-welded joints. CONCLUSIONS: The tensile strengths of the as-cast joints were higher than those for the laser-welded joints, and both were higher than the electric-brazed joint strengths. 相似文献