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101.
Maria E. Nadal Edward A. Early Will Weber Robert Bousquet 《Color research and application》2008,33(2):94-99
The NIST 0:45 reflectometer measures the spectral reflectance factor at an influx angle of 0° and an efflux angle of 45° of colored, nonfluorescent specimens at room temperature, with widths ranging from 3 to 10 cm and heights from 3 to 20 cm and with an uncertainty of less than 0.5 in color difference units. Published in 2008 by John Wiley & Sons, Inc. Col Res Appl, 33, 94–99, 2008 相似文献
102.
Carbon based multilayer systems for highly loaded forming tools Amorphous hydrogenated carbon (metal‐free a‐C:H and metal‐containing a‐C:H:Me) films respond very sensitively to local overloads. For example during forming tool operations, hard abrasive particles and locally high stresses on the coating surface can cause crack initiation and early coating failure. Compared to the high hardness, wear resistance and excellent friction properties, in many cases the adhesion of a‐C:H films is relatively insufficient. Adhesion and overload resistance of a‐C:H and a‐C:H:Me, prepared by reactive sputtering, can be influenced in a wide range by different interlayer systems. In the present report the wear mechanism of amorphous carbon coatings and the influence of different metallic, metal nitride and metal carbide interlayers on the growth structure, the adhesion and the load resistance will be reported. Two well adapted multi‐coating systems, successfully tested for highly loaded tools and components, will be presented. 相似文献
103.
Thoracoscopy provides a minimally invasive technique for the diagnosis and management of many posterior mediastinal masses. Benign neurogenic tumors, esophageal tumors, and bronchogenic cysts all can be approached using video-assisted thoracic surgical (VATS) techniques. Malignant lesions are still best approached via open thoracotomy. VATS techniques allow for less pain and dysfunction and can result in shortened hospital stays. 相似文献
104.
Pseudoexstrophy is a rare, mild exstrophy variant which involves the major musculoskeletal defects of the exstrophy complex without any associated defect in the urinary system. A case is reported presenting at birth as an umbilical positional anomaly. Differential diagnosis and management are reviewed. 相似文献
105.
CD Holyoak M Stratford Z McMullin MB Cole K Crimmins AJ Brown PJ Coote 《Canadian Metallurgical Quarterly》1996,62(9):3158-3164
The weak acid sorbic acid transiently inhibited the growth of Saccharomyces cerevisiae in media at low pH. During a lag period, the length of which depended on the severity of this weak-acid stress, yeast cells appeared to adapt to this stress, eventually recovering and growing normally. This adaptation to weak-acid stress was not due to metabolism and removal of the sorbic acid. A pma1-205 mutant, with about half the normal membrane H+-ATPase activity, was shown to be more sensitive to sorbic acid than its parent. Sorbic acid appeared to stimulate plasma membrane H+-ATPase activity in both PMA1 and pma1-205. Consistent with this, cellular ATP levels showed drastic reductions, the extent of which depended on the severity of weak-acid stress. The weak acid did not appear to affect the synthesis of ATP because CO2 production and O2 consumption were not affected significantly in PMA1 and pma1-205 cells. However, a glycolytic mutant, with about one-third the normal pyruvate kinase and phosphofructokinase activity and hence a reduced capacity to generate ATP, was more sensitive to sorbic acid than its isogenic parent. These data are consistent with the idea that adaptation by yeast cells to sorbic acid is dependent on (i) the restoration of internal pH via the export of protons by the membrane H+-ATPase in an energy-demanding process and (ii) the generation of sufficient ATP to drive this process and still allow growth. 相似文献
106.
OBJECTIVE: To report a case of probable famotidine-induced mixed hepatocellular jaundice. CASE SUMMARY: A 55-year-old man presented with a one-month history of mid-epigastric pain. Initial physical examination and laboratory studies, including liver enzyme concentration tests, were unrevealing. A diagnosis of gastritis was made and ranitidine was prescribed. Following one week of therapy, the patient's symptoms had not improved and therapy was changed to famotidine and sucralfate. Approximately one week later the patient presented with jaundice. Liver enzyme concentrations were elevated and the patient was hospitalized for further evaluation. Five days following discontinuation of famotidine, liver enzyme concentrations were normal and jaundice had resolved. Further tests did not reveal any pathologic etiology. DISCUSSION: Hepatic changes have occurred in patients receiving histamine2-antagonists; ranitidine and cimetidine have been cited most frequently. In general, the elevations are mild, transient, and return to baseline with continued therapy. This is one of the first case reports of probable famotidine-induced mixed hepatocellular jaundice. CONCLUSIONS: There was a temporal relationship between the patient's signs and symptoms and initiation of famotidine. No identifiable factors contributed to the elevated liver enzyme concentrations and jaundice. 相似文献
107.
Serum lipids and incidence of coronary heart disease. Findings from the Systolic Hypertension in the Elderly Program (SHEP) 总被引:3,自引:0,他引:3
PH Frost BR Davis AJ Burlando JD Curb GP Guthrie JL Isaacsohn S Wassertheil-Smoller AC Wilson J Stamler 《Canadian Metallurgical Quarterly》1996,94(10):2381-2388
BACKGROUND: The association of serum lipids with coronary heart disease has been studied extensively in middle-aged men and, to a lesser extent, in similar women. Less well defined are lipid variables predictive of CHD in individuals of age > or = 60 years. METHODS AND RESULTS: The Systolic Hypertension in the Elderly Program recruited 4736 persons (mean age, 72 years; 14% were black; and 43% were men). Mean systolic and diastolic blood pressures were 170 and 77 mm Hg, respectively. Baseline mean total cholesterol was 6.11 mmol/L (236 mg/dL); HDL cholesterol, 1.39 mmol/L (54 mg/dL); and non-HDL cholesterol, 4.72 mmol/L (182 mg/dL). Triglyceride levels were 1.62 mmol/L (144 mg/dL) for fasting participants and 1.78 mmol/L for the total group. LDL cholesterol, estimated in fasting samples with triglycerides of < 4.52 mmol/L, averaged 3.98 mmol/L (154 mg/dL). Mean follow-up was 4.5 years. In multivariate Cox regression analyses, baseline total, non-HDL, and LDL cholesterol levels and the ratios of total, non-HDL, and LDL to HDL cholesterol were significantly related to CHD incidence. HDL cholesterol and triglycerides were not significant in these analyses. In fasting participants with triglyceride levels of < 4.52 mmol/L, a 1.03 mmol/L (40 mg/dL) higher baseline total, non-HDL, or LDL cholesterol was associated with a 30% to 35% higher CHD event rate. CONCLUSIONS: The results of this study support the concept that serum lipids are CHD risk factors in older Americans. 相似文献
108.
BACKGROUND: In end-stage renal disease, average bone mineral density has been reported to be normal or only modestly reduced, more so in the cortical bone. The purpose of the present study was to explore the potential use of quantitative ultrasound, a method reflecting both quantitative and qualitative properties of bone, in assessing bone status in patients on maintenance haemodialysis. METHODS: We studied 71 patients (age 17-81 years, time on dialysis 0-18 years). The speed of sound waves (tSOS; m/s) propagating along the cortical bone has been determined at the tibial shaft. tSOS results were expressed as Z scores, i.e. units of standard deviations from age- and sex-matched normal mean values, and correlated with relevant clinical and biochemical variables. RESULTS: SOS Z score averaged -2. 0 (range -6.8 to 0.6; P<0.001) and was negative in 93% of the patients. Significant inverse correlations were found between SOS Z score and both time on dialysis (r=-0.52; P<0.0001) and serum PTH (r=-0.39; P=0.0002). Markedly reduced SOS Z score, below -2, was found in 80% of the patients whose PTH levels exceeded 34 pmol/l (five times the upper normal limit), compared with 43% of the patients whose PTH levels were below 34 pmol/l(P=0.04). Compared to patients without bone pain (n=51), subjects with bone pain (n=20) had somewhat lower SOS Z scores -2.5+/-2.0 versus -1.8+/-1.4; P=0. 08), but this could be accounted for by longer time on dialysis. CONCLUSIONS: tSOS is substantially reduced in the majority of haemodialysed patients and is related to time on dialysis and serum PTH level. The clinical value of this novel method needs further exploration. 相似文献
109.
110.
Phenotypic analysis of antigen-specific T lymphocytes 总被引:4,自引:0,他引:4
JD Altman PA Moss PJ Goulder DH Barouch MG McHeyzer-Williams JI Bell AJ McMichael MM Davis 《Canadian Metallurgical Quarterly》1996,274(5284):94-96
Identification and characterization of antigen-specific T lymphocytes during the course of an immune response is tedious and indirect. To address this problem, the peptide-major histocompatability complex (MHC) ligand for a given population of T cells was multimerized to make soluble peptide-MHC tetramers. Tetramers of human lymphocyte antigen A2 that were complexed with two different human immunodeficiency virus (HIV)-derived peptides or with a peptide derived from influenza A matrix protein bound to peptide-specific cytotoxic T cells in vitro and to T cells from the blood of HIV-infected individuals. In general, tetramer binding correlated well with cytotoxicity assays. This approach should be useful in the analysis of T cells specific for infectious agents, tumors, and autoantigens. 相似文献