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A patient with spontaneous acute spinal cord ischemia successfully treated with cerebrospinal fluid drainage is reported. There are no consensus guidelines on the management of spinal cord ischemia. Various preventive and rehabilitative measures have been suggested, but the best treatment remains unknown.  相似文献   
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DL-alpha-Difluoromethylornithine is an enzyme-activated inhibitor of ornithine decarboxylase and an antagonist of polyamine metabolism that has been successful in clinical trials against West African sleeping sickness caused by Trypanosoma brucei gambiense. Its potential for use against the more virulent East African form of the disease, caused by T. brucei rhodesiense, is not certain. We examined 14 East African clinical isolates from the Kenya Trypanosomiasis Research Institute strain bank plus 2 established isolates for susceptibility to DL-alpha-difluoromethylornithine and to standard trypanocides. Seven of 16 strains were partially or totally refractory to DL-alpha-difluoromethylornithine in our test system. Four strains were also refractory to arsenical drugs, and five were refractory to diamidines. The results indicate that other novel agents or combinations of established agents may be needed for chemotherapy of East African disease.  相似文献   
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Silicon substitution in the calcium phosphate bioceramics   总被引:12,自引:0,他引:12  
Pietak AM  Reid JW  Stott MJ  Sayer M 《Biomaterials》2007,28(28):4023-4032
Silicon (Si) substitution in the crystal structures of calcium phosphate (CaP) ceramics such as hydroxyapatite (HA) and tricalcium phosphate (TCP) generates materials with superior biological performance to stoichiometric counterparts. Si, an essential trace element required for healthy bone and connective tissues, influences the biological activity of CaP materials by modifying material properties and by direct effects on the physiological processes in skeletal tissue. The synthesis of Si substituted HA (Si-HA), Si substituted alpha-TCP (Si-alpha-TCP), and multiphase systems are reviewed. The biological performance of these Si substituted CaP materials in comparison to stoichiometric counterparts is discussed. Si substitution promotes biological activity by the transformation of the material surface to a biologically equivalent apatite by increasing the solubility of the material, by generating a more electronegative surface and by creating a finer microstructure. When Si is included in the TCP structure, recrystallization to a carbonated HA is mediated by serum proteins and osteoblast-like cells. Release of Si complexes to the extracellular media and the presence of Si at the material surface may induce additional dose-dependent stimulatory effects on cells of the bone and cartilage tissue systems.  相似文献   
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BACKGROUND: Body mass index (BMI) and bone mineral density (BMD) are positively correlated in several studies, but few data relate bone density, lipid profile and anthropometric measures. AIM: To investigate these relationships in a large, well-characterized cohort of men and women (The Hertfordshire Cohort Study). METHODS: Men (n = 465) and women (n = 448) from Hertfordshire, UK were recruited. Information was available on demographic and lifestyle factors, anthropometric measurements, body fat percentage, fasting triglycerides, cholesterol (total, HDL, LDL), apolipoprotein (a) and apolipoprotein (b); bone mineral density (BMD) was recorded at the lumbar spine and total femur. RESULTS: BMD at the lumbar spine (males r = 0.15, p = 0.001; females r = 0.14, p = 0.003) and total femoral region (males r = 0.18, p = 0.0001; females r = 0.16, p = 0.0008) was related to serum triglyceride level, even after adjustment for waist-hip ratio, age, social class and lifestyle factors, but not if body fat percentage was substituted for waist-hip ratio in the regression model. Fasting HDL cholesterol level was related to lumbar spine BMD in women (r = -0.15, p = 0.001) and total femoral BMD in both sexes (males r = -0.15, p = 0.002; females r = -0.23, p < 0.0001); these relationships were also attenuated by adjustment for body fat percentage but not waist-hip ratio. No relationships were seen between total or LDL cholesterol with BMD. DISCUSSION: In this cohort, relationships between lipid profile and BMD were robust to adjustment for one measure of central obesity (waist-hip ratio), but not total body fat. This broadly supports the idea that adiposity may confound the relationship between lipids and bone mass.  相似文献   
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BACKGROUND: Sarcopenia is defined as the loss of skeletal muscle mass and strength with aging. Recent epidemiological studies have shown that men and women who grew less well in early life have lower muscle strength. Our objective was to investigate the relationship between birth weight, infant growth, and the development of sarcopenia. METHODS: We studied 730 men and 673 women, of known birth weight and weight at 1 year, who were born in Hertfordshire, U.K., between 1931 and 1939. Participants completed a health questionnaire, and we measured their height, weight, and grip strength. Standard deviation scores for birth weight, and for infant growth conditional on birth weight, were analyzed in relation to grip strength before and after adjustment for adult size. RESULTS: Grip strength was most strongly associated with birth weight in men (r = 0.19, p < .001) and women (r = 0.16, p < .001). These relationships remained significant after adjustment for adult height and weight. In contrast, the associations with infant growth were weakened after allowing for adult size. Adjustment for age, current social class, physical activity, smoking, and alcohol did not affect these results. CONCLUSIONS: Birth weight is associated with sarcopenia in men and women, independently of adult height and weight. The influence of infant growth on long-term muscle strength appears to be mediated through adult size. Sarcopenia may have its origins in early life, and identifying influences operating across the whole life course may yield considerable advances in developing effective interventions.  相似文献   
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