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991.
SO Tabbara MK Sidawy AR Frost KR Brosky V Coles S Hecht G Radcliffe ME Sherman 《Canadian Metallurgical Quarterly》1998,84(6):355-360
The authors measured plasma metalloproteinase (MMP)-9 and corresponding monocyte mRNA in 20 patients with septic shock. Plasma MMP-9 concentrations and monocyte MMP-9 mRNA levels were significantly higher in the 10 nonsurviving patients with septic shock than in 10 surviving patients and 25 normal controls. Hemoperfusion using polymyxin B immobilized on fibers (PMX-F), a reportedly effective treatment for septic shock, was studied for effects on MMP-9 in the patients. Increases in plasma MMP-9 concentrations and corresponding monocyte mRNA levels were attenuated significantly by PMX-F treatment in both nonsurviving and surviving patients. These data suggest that plasma MMP-9 concentrations and monocyte MMP-9 mRNA levels may be useful prognostic markers in septic shock, and that PMX-F treatment affects MMP-9. 相似文献
992.
Unnikrishnan Nair Saraswathy Hareesh Martin Sternitzke Rolf Janssen Nils Claussen Krishna Gopakumar Warrier 《Journal of the American Ceramic Society》2004,87(6):1024-1030
Dense alumina/5 vol% SiC nanocomposites were prepared by sol–gel processing using nanosized (180 nm) precoated SiC powders and a commercial boehmite sol. The SiC powder was precoated with boehmite by a controlled heterogeneous precipitation from an aluminum nitrate solution. The coated SiC powder was then dispersed in a boehmite sol, gelled, calcined, and densified by gas pressure sintering under argon atmosphere at 7–8 MPa pressure. The dependence of the calcination conditions on densification, the effect of seeding on the microstructural development, as well as the mechanical behavior of the sintered specimens, are presented and discussed. 相似文献
993.
Absorption of orally administered (-)-epicatechin (EC) in rats was studied to obtain plasma pharmacokinetic profiles of EC metabolites. Rats were administered 172 micromol/kg body weight of EC, and blood was collected from the tail for 8 h after administration. Seven groups of compounds possessing the basic structure of EC were identified by using a combination of enzymatic hydrolysis, HPLC and electron impact mass spectrometry. Metabolites were quantified with a new, simple and sensitive method using HPLC with electrochemical detection. Ingested EC was absorbed from the alimentary tract and was present in the rat common blood circulation in the form of glucuronide and/or sulfate conjugates. The activity of conjugative enzymes in rat tissues was studied. The highest activity of glucuronosyltransferase was found in the intestinal mucosa of both of the small and large intestine; the highest activity of phenolsulfotransferase occurred in the liver, and that of catechol-O-methyl transferase was found in the liver and kidney. It has been proposed that the first detoxification step of dietary EC, namely, glucuronidation, occurs at the level of the intestinal mucosa in rats, and EC enters the common blood circulation exclusively in the glucuronized form. The compound is then sulfated in the liver and methylated in the liver and kidney. Because ingested EC undergoes extensive conjugation, its biological activities previously demonstrated in vitro may not be occurring in in vivo systems. 相似文献
994.
MK Siddiqui MC Saxena AK Bhargava CR Murti D Kutty 《Canadian Metallurgical Quarterly》1981,15(2):77-79
Umbilical cord blood collected during labor of 100 Indian women was analyzed for organochlorine pesticides by gas-liquid chromatography with electron-capture detection. Significant levels of p,p'-DDT and its metabolites, p,p'-TDE and p,p'-DDE, as well as alpha-, beta-, and gamma-isomers of BHC were estimated. Residues in the neonatal blood were related to age, dietetic habits, and area of residence of the mothers. The study highlights the extent of placental transfer of the body burden of toxic chemicals from the mother to the fetus. 相似文献
995.
996.
Low-speed isokinetic exercise has been recommended to exert a maximal contraction and produce greater muscle torque than high-speed exercise in young adults. The purpose of this study was to compare the effectiveness of low- and high-speed isokinetic exercise programs for increasing muscle torque in young and elderly people. Twenty healthy elderly and 20 young subjects participated. The elderly subjects were divided into two groups. One group performed high-speed (300 degrees/s) isokinetic exercise training three times a week for the dominant-side knee extensor and low-speed (60 degrees/s) exercise for the non-dominant side for 6 weeks. The other group was trained using the reverse exercise regime. The training program for the young subjects was the same as that for the elderly groups. All subjects had their knee extensor torque evaluated with an isokinetic test before and at 2-week intervals during the training program. For young and elderly groups, both high- and low-speed isokinetic exercise training increased extensor torque in low- and high-speed tests. For the young group, low-speed exercise effectively improved muscle torque at low and high speeds. The improvement in slow muscle torque was significantly greater than that in fast muscle torque. For the elderly subjects, high-speed isokinetic exercise produced the greatest muscle torque at high speed in the first 2 weeks of training, and demonstrated a sharp increase in muscle torque in the final 2 weeks. Low-speed exercise frequently caused knee stress and the inability of some elder subjects to continue the exercises with maximal effort. Our findings indicate that high-speed exercise may be more appropriate for the elderly, and low-speed exercise may be more appropriate for younger people. 相似文献
997.
998.
999.
BI Cohen MK Pagnillo I Newman BL Musikant AS Deutsch 《Canadian Metallurgical Quarterly》1998,79(5):520-525
BACKGROUND: Although the use of extracorporeal life support (ECLS) following repair of congenital heart defects in children is increasing, the criteria for ECLS usage in these patients is not well defined. The overall survival of such patients is disappointingly low and may depend on both the indication for support and the time at which ECLS is commenced. METHODS: Between January 1993 and December 1996, 727 children underwent surgery for congenital heart defects at our institution with an overall hospital mortality of 5.8% (42 children). Nine of these children were treated with ECLS postoperatively. There were seven males and two females with a mean age of 7.2 months (range 2 weeks-3 years). Seven children could not be weaned from cardiopulmonary bypass (CPB) in the operating theatre. A further two were treated with ECLS later on during the postoperative period (commenced at 14 and 48 h). Full veno-arterial extra corporeal membrane oxygenation (ECMO) support was used in all children except one in whom a left ventricular assist device (LVAD) was used. RESULTS: The median duration of support was 121 h (range 15-648 h). Four children (44%) were weaned from support and two of these are long-term survivors. Of the seven children in whom ECLS was instituted because of failure to wean from CPB, there was one long term survivor (LVAD support). Of the two patients in whom ECLS was instituted during the post-operative period there is one long-term survivor. CONCLUSIONS: Weaning form ECLS and decannulation in 44% of our patients is comparable to other series of post-cardiotomy patients requiring ECLS. However, full veno-arterial ECMO instituted because of a failure to wean from CPB during corrective surgery is associated with an extremely poor outcome (zero long-term survivors in six patients). 相似文献
1000.
PURPOSE: To study the alterations in endothelial cell count and morphology after pediatric cataract surgery using currently practiced techniques. SETTING: L.V. Prasad Eye Institute, Hyderabad, India. METHODS: In a prospective nonrandomized series comprising 20 eyes of 14 children with congenital or developmental cataract, endothelial cell loss from cataract surgery was evaluated. Mean patient age was 9.3 years (range 5 to 15 years). Extracapsular cataract extraction (ECCE) with intraocular lens (IOL) implantation was performed in 11 eyes (Group 1). Primary posterior capsulotomy and anterior vitrectomy were performed with ECCE and IOL implantation in 9 eyes (Group 2). Noncontact specular microscopy was done preoperatively and 6 to 8 and 24 to 36 weeks postoperatively. Endothelial cell loss, alteration in the coefficient of variation, and the change in the number of hexagonal cells were determined by semiautomated analysis of endothelial pictures. RESULTS: Mean endothelial cell loss was 198.39 cells/mm2 (5.28%) in Group 1 and 295.17 cells/mm2 (7.50%) in Group 2 at 24 to 36 weeks. There was no statistically significant difference in alteration in endothelial cell count and morphology between the 2 groups. CONCLUSIONS: The results suggest that endothelial cell loss with currently practiced techniques of pediatric cataract surgery is within acceptable limits. 相似文献