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61.
M. N. Palatnikov O. B. Shcherbina V. V. Efremov A. A. Yanichev N. V. Sidorov V. V. Pasichnyi 《Inorganic Materials》2013,49(9):909-915
The structure and mechanical characteristics of ceramic Nb2O5 and ceramic materials produced from coprecipitated Nb2(1 ? y)Ta2y O5 pentoxides by a conventional ceramic processing technique and exposure to high-intensity light have been studied by scanning probe microscopy and Raman spectroscopy. 相似文献
62.
R Lewis S Kapur C Jones J DaSilva GM Brown AA Wilson S Houle RB Zipursky 《Canadian Metallurgical Quarterly》1999,156(1):72-78
BACKGROUND: In the FRISC trial, dalteparin 120 IU/kg body weight twice daily for unstable coronary artery disease was safe and reduced the risk of new coronary events. This risk reduction was maintained during the following extended treatment with a fixed dose of 7500 IU dalteparin once daily. METHODS AND RESULTS: Minor bleeding was more frequent in women compared with men: relative risk (CI) 2.88 (1.78 to 4.67) during the weight-adjusted and 2.36 (1.37 to 2.63) during the fixed dose treatment. The anti-Xa activity determined in samples (n = 175) obtained during the acute phase treatment was higher in women compared with men (P <.001) and in nonsmokers compared with smokers (<.001) in multiple regression analysis. Also, during the fixed-dose treatment (n = 131) an independent relation between anti-Xa activity and sex (P <.001), but not smoking habits, persisted. CONCLUSION: To improve future low-molecular-weight heparin dose regimens for the treatment of acute coronary syndromes, it might be important to consider the influence of sex and smoking habits. 相似文献
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Inhaled nitric oxide (NO) clearly decreased pulmonary vascular resistance in pediatric patients with pulmonary hypertension, regardless of the underlying origin of the pulmonary hypertension. In persistent pulmonary hypertension of the neonate (PPHN) and CHD, the use of inhaled NO appears to improve the outcome of these patients. In acute respiratory distress syndrome (ARDS) and surfactant deficiency the role of inhaled NO therapy remains unclear. The use of inhaled NO is safe in a carefully monitored setting with a delivery system designed to minimize the generation of NO2. 相似文献
66.
DA Toke WL Bennett DA Dillon WI Wu X Chen DB Ostrander J Oshiro A Cremesti DR Voelker AS Fischl GM Carman 《Canadian Metallurgical Quarterly》1998,273(6):3278-3284
Diacylglycerol pyrophosphate (DGPP) is involved in a putative novel lipid signaling pathway. DGPP phosphatase (DGPP phosphohydrolase) is a membrane-associated 34-kDa enzyme from Saccharomyces cerevisiae which catalyzes the dephosphorylation of DGPP to yield phosphatidate (PA) and then catalyzes the dephosphorylation of PA to yield diacylglycerol. Amino acid sequence information derived from DGPP phosphatase was used to identify and isolate the DPP1 (diacylglycerol pyrophosphate phosphatase) gene encoding the enzyme. Multicopy plasmids containing the DPP1 gene directed a 10-fold overexpression of DGPP phosphatase activity in S. cerevisiae. The heterologous expression of the S. cerevisiae DPP1 gene in Sf-9 insect cells resulted in a 500-fold overexpression of DGPP phosphatase activity over that expressed in wild-type S. cerevisiae. DGPP phosphatase possesses a Mg2+-independent PA phosphatase activity, and its expression correlated with the overexpression of DGPP phosphatase activity in S. cerevisiae and in insect cells. DGPP phosphatase was predicted to be an integral membrane protein with six transmembrane-spanning domains. The enzyme contains a novel phosphatase sequence motif found in a superfamily of phosphatases. A dpp1Delta mutant was constructed by deletion of the chromosomal copy of the DPP1 gene. The dpp1Delta mutant was viable and did not exhibit any obvious growth defects. The mutant was devoid of DGPP phosphatase activity and accumulated (4-fold) DGPP. Analysis of the mutant showed that the DPP1 gene was not responsible for all of the Mg2+-independent PA phosphatase activity in S. cerevisiae. 相似文献
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AS Shashkov NA Paramonov SP Veremeychenko H Grosskurth GM Zdorovenko YA Knirel NK Kochetkov 《Canadian Metallurgical Quarterly》1998,306(1-2):297-303
The O-specific polysaccharide of Pseudomonas fluorescens biovar B, strain IMV 247, was studied by acid hydrolysis, GLC-MS and 1H and 13C NMR spectroscopy, including 1D and 2D NOE, 2D hybrid TOCSY and ROESY (TORO), and 2D H-detected heteronuclear multiple-bond correlation (HMBC) experiments. The polysaccharide was found to contain L-rhamnose, 3.6-dideoxy-3-[(S)-3-hydroxybutyramido]-D-glucose (D-Qui3NHb), 2-acetamido- 2,4,6-trideoxy-4-[(S)-3-hydroxybutyramido-D-glucose (D-QuiNAc4NHb) and 2-acetamido-2- deoxy-D-galacturonic acid (D-GalNAcA). Partial acid hydrolysis of the polysaccharide resulted in a non-reducing GalNAcA-->QuiNAc4NHb disaccharide with the 3-hydroxybutyryl group glycosylated intramolecularly by the QuiN4N residue. The following structure of the tetrasaccharide repeating unit of the polysaccharide was established:-->4) -alpha-D-GalpNAcA-(1-->3)- alpha-D-QuipNAc4NHb-(1-->2)-beta-D-Quip3NHb-(1-->2)-alpha-L- Rhap(1-->. 相似文献
70.
GM McCarthy JD Awde H Ghandi M Vincent WI Kocha 《Canadian Metallurgical Quarterly》1998,34(6):484-490
Oral mucositis is a dose-limiting toxicity of 5-fluorouracil (5-FU). This prospective cohort study investigated factors associated with mucositis in patients receiving 5-FU for cancer of the digestive tract. Sixty-three patients (mean age 65 years) completed self-administered questionnaires and had interviews, oral examinations and unstimulated whole salivary flow measurements at baseline and follow-up appointments. The duration of follow-up was 2 months. Predictor variables included sociodemographic data, body surface area, diabetes, smoking, alcohol consumption, salivary flow, oral hygiene, presence of prostheses, performance status, regimen of cytotoxic drugs, hematological data, and herpes simplex virus antibody titer. Forty-six per cent of patients developed at least one episode of oral mucositis during cytotoxic treatment. Pearson's chi-square analysis showed that mucositis was significantly associated with xerostomia at baseline, xerostomia during chemotherapy, and lower baseline neutrophil counts (P < or = 0.05). Multiple logistic regression analysis indicated that xerostomia at baseline (odds ratio, OR = 10.0), or baseline neutrophil level under 4000 cells/mm3 (OR = 3.9) were significant predictors of mucositis. Taking into account the effect of neutrophil level at baseline, xerostomia during chemotherapy (OR = 4.5) was also a significant predictor of mucositis. The results showed that xerostomia and lower baseline neutrophil levels are significantly associated with oral mucositis. These variables should be taken into consideration in the design of intervention studies to reduce the frequency and severity of mucositis. More research is required to investigate the role of saliva and neutrophils in the pathogenesis of chemotherapy-induced mucositis. 相似文献