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941.
Ferdinand P. Ferragu O. Lechien J.L. Lescop B. Magne S. Marty V. Rougeault S. Kotrotsios G. Neuman V. Depeursinge Y. Michel J.B. Van Uffelen M. Varelas D. Berthou H. Pierre G. Renouf C. Jarret B. Verbandt Y. Stevens W. Voet M.R.H. Toscano D. 《Lightwave Technology, Journal of》1995,13(7):1303-1313
Recent developments of stability control in mines, essentially based on Ge-doped fiber Bragg gratings (FBG) are reported including results about the different aspects of the system: accurate characterizations of FBG, sensor network topology and multiplexing method, user interface design and sensor packaging 相似文献
942.
STUDY OBJECTIVE: To evaluate insurance status and frequency of use of emergency services in adults with sickle cell disease. DESIGN: Retrospective analysis of visits. SETTING: Emergency department and outpatient clinics of an urban university hospital. PARTICIPANTS: One hundred seventy-two subjects, who made 771 visits to the ED during 1990. RESULTS: Of the 172 subjects, 31 were covered by commercial insurance, 32 were covered by Medicare, and 109 were covered by Medicaid or were uninsured. Insurance status and frequency of use of emergency services were independent (P > .05). On discriminant analysis, Medicaid-covered and uninsured subjects were correctly classified, but commercially insured and Medicare subjects were not. Medicaid and uninsured subjects were more likely to be younger and to live closer to the hospital (P < .00005). High-frequency users of emergency services were discriminated from low-frequency users. High-frequency users were more likely to be younger, to be users of primary-care services, and to live closer to the hospital (P = .0004). CONCLUSION: Provision of primary-care services or stable insurance in the form of commercial insurance or Medicare did not decrease use of emergency services in subjects with sickle cell disease in a group of patients selected from one urban academic ED. 相似文献
943.
L Fr?yland DK Asiedu H Vaagenes A Garras O Lie GK Totland RK Berge 《Canadian Metallurgical Quarterly》1995,36(12):2529-2540
The mechanism behind the hypolipidemic effect of tetradecylthioacetic acid (CMTTD, a non-beta-oxidizable 3-thia fatty acid) was studied in hamsters fed a high cholesterol diet (2%), which resulted in hyperlipidemia. Treating hyperlipidemic hamsters with CMTTD resulted in a progressive hypocholesterolemic and hypotriacylglycerolemic effect. Decreased plasma cholesterol was followed by a 39% and 30% reduction in VLDL-cholesterol and LDL-cholesterol, respectively. In contrast, the HDL-cholesterol content was not affected, thus decreasing the VLDL-cholesterol/HDL-cholesterol and LDL-cholesterol/HDL-cholesterol ratios. 3-Hydroxy-3-methylglutaryl- (HMG) CoA reductase activity and its mRNA level were unchanged after CMTTD administration. Also, the LDL receptor and LDL receptor-related protein (LRP-4) mRNAs were unchanged. The decrease in plasma triacylglycerol was accompanied by a 45% and 56% reduction in VLDL-triacylglycerol and LDL-triacylglycerol, respectively. The hypolipidemic effect of CMTTD was followed by a 1.4-fold increase in mitochondrial fatty acid oxidation and a 2.3-fold increase in peroxisomal fatty acid oxidation. CMTTD treatment led to an accumulation of dihomo-gamma-linolenic acid (20:3n-6) in liver, plasma, very low density lipoprotein, and heart. Noteworthy, CMTTD accumulated more in the heart, plasma, and VLDL particles compared to the liver, and in the VLDL particle alpha-linolenic acid (18:3n-3) decreased whereas eicosatetraenoic acid (20:4n-3) increased. In addition, linoleic acid (18:2n-6) and the total amount of polyunsaturated fatty acids decreased, the latter mainly due to a decrease in n-6 fatty acids. The present data show that CMTTD was detected in plasma and incorporated into VLDL, liver, and heart. The relative incorporation (mol%) of CMTTD was heart > VLDL > liver. In conclusion, CMTTD causes both a hypocholesterolemic and hypotriacylglycerolemic effect in hyperlipidemic hamsters. 相似文献
944.
I Panfoli F Rosina L Musante A Morelli C Cugnoli IM Pepe 《Canadian Metallurgical Quarterly》1995,44(5):247-257
Active Ca2+ transport was measured in microsomal vesicles prepared from bovine retinae and was compared with that in disk membranes of the photoreceptor cells of the same retina. The 45Ca uptake was dependent on the presence of Mg(2+)-ATP and was inhibited by vanadate or when GTP substituted for ATP. The dependence of calcium uptake on the external free Ca2+ concentration gave a KM = 13 microM or a KM = 0.1 microM for disks and microsomal vesicles, respectively. A phosphorylated intermediate (E-P) of Ca(2+)-ATPase of about 100 kDa was isolated in microsomal vesicles. The E-P formation was strongly inhibited by thapsigargin and partially by 2,5-di-(-butyl)benzohydroquinone. Digestion of disks or microsomes with calpain had no effect on the phosphorylated intermediate, while digestion with trypsin produced two fragments of approximately 55 kDa and 35 kDa. These results suggest that bovine retinal microsomes contain a calcium pump belonging to the SERCA family. 相似文献
945.
946.
K Opatrny L Vít S Opatrná V Polakovic F Sefrna S Sulková K Opatrny 《Canadian Metallurgical Quarterly》1995,19(8):814-820
Two studies designed to investigate the effect of recombinant human erythropoietin (rHuEPO) treatment of anemia in chronic dialysis patients on hemocompatibility were conducted. Study 1, whose main aim was to establish whether treatment with rHuEPO enhances coagulation activation during dialysis, included 15 patients before rHuEPO therapy at a mean hematocrit (HCT) of 22.3% and then during therapy at a HCT of 29.3%. The plasma concentrations of the thrombin-antithrombin III complex were not higher during rHuEPO therapy than before it when performing hemodialysis with a Cuprophan membrane. No significant difference was demonstrated either in the values of activated clotting times (Hemochron), thrombocyte or white blood cell counts (Coulter S+II), or in plasma C5a concentrations (ELISA) established during dialysis sessions before and during rHuEPO therapy. In Study 2, which focused primarily on the question of whether or not rHuEPO therapy increases thrombocyte activation during hemodialysis, 8 patients on chronic dialysis were examined both before therapy at a mean HCT value of 22.1% and during rHuEPO therapy at a HCT of 31.5%, invariably during dialysis with either a Cuprophan or polyacrylonitrile (AN69HF) membrane. The plasma concentrations of beta-thromboglobulin (ELISA) did not differ between the examinations made during rHuEPO and before rHuEPO therapy; however, statistically significant differences were found between dialysis sessions involving Cuprophan and AN69HF membranes. No significant difference between examination before and during rHuEPO was demonstrated in activated clotting time nor thrombocyte and white blood cell counts in this study either. The authors conclude that rHuEPO therapy does not enhance coagulation activation during hemodialysis, does not have an effect on thrombocyte activation, and does not influence complement activation and changes in white blood cell counts. 相似文献
947.
948.
R Tew EA Guthrie FH Creed L Cotter S Kisely B Tomenson 《Canadian Metallurgical Quarterly》1995,39(8):977-985
Ninety consecutive patients who were admitted to hospital with acute chest pain were followed-up five years later. At the time of the original admission, all of the patients received a detailed physical and psychiatric evaluation. Seventy-one patients were diagnosed as having ischaemic heart disease, and 19 were diagnosed as having nonspecific chest pain. Patients with nonspecific pain were younger, consumed greater amounts of alcohol, smoked more than their organic counterparts, and were more likely to suffer from psychiatric disorder. The five-year assessment was carried out using a self-report questionnaire. Of the original 71 patients with ischaemic heart disease, 14 had died; 43 questionnaires were returned, 80.2% of the original sample. Sixteen (84.9%) of the patients with nonspecific pain were followed up; none had died. Both groups were predominantly male. The patients with nonspecific pain still smoked more than the patients with ischaemic heart disease, and they had significantly more symptoms of anxiety. The overall prevalence of psychiatric morbidity remained high, however, in both groups. Patients who had psychiatric illness at the time of the original assessment were more anxious at follow-up and more likely to complain of chest pain than those who had been well. Patients with nonspecific chest pain continued to seek treatment on a regular basis from their general practitioners either for chest pain or for other symptoms, but few were in frequent contact with hospital services. The possible preventive effects of psychiatric intervention at an earlier stage in both groups of patients needs to be investigated. 相似文献
949.
R Pérez Ferrari L Lambra?o R Aranda L Ferrabone 《Canadian Metallurgical Quarterly》1993,18(3):229-232
We studied the incidence of infection with Helicobacter pylori in Panamanians with chronic dyspepsia, gastric or duodenal ulcer, gastritis or gastric cancer. The histopathology was positive in 54 (81%) of 66 patients; the urea test was positive in 52 (82.5%) of 63 cases; the impromptu was positive in 51 (79.6) of 64 patients; the endoscopic examination was positive in 64 (82.9%) of 77 examinations. 相似文献
950.
B. L. Bozhenko L. I. Bedenko V. L. Kovtun G. G. Chernyshov 《Journal of Engineering Physics and Thermophysics》1993,64(4):328-333
An analysis of the kinetics of gas dissolution in a liquid metal flow is performed. It is shown that due to a high pouring rate and specific surface of the flow, the flow in the arc of molten filler metal, as distinct from the flow of liquid metal during its pouring, leads to intense saturation of the melt with gas.Volgograd Branch of the Novocherkassk Polytechnic Institute. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 64, No. 4, pp. 414–420, April, 1993. 相似文献