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81.
Rico H Roca-Botran C Hernández ER Seco C Paez E Valencia MJ Villa LF 《Menopause (New York, N.Y.)》2000,7(6):413-416
OBJECTIVE: The effect of a copper supplement on preventing bone mass loss induced by ovariectomy in rats was investigated. DESIGN: Three groups of fifteen 100-day-old female Wistar rats, each with a mean initial weight of approximately 260 g per animal, were selected for a 30-day experiment. One group of 15 ovariectomized rats was fed a diet supplemented with 15 mg of copper per kilogram of feed. The other two groups: 15 ovariectomized and 15 Sham- ovariectomized rats did not receive the supplement. Morphometric (weight and length) and densitometric studies with dual-energy x-ray absorptiometry were performed on the whole femur and the fifth lumbar vertebra of each animal at the end of the 30-day period. RESULTS: The ovariectomized rat group fed a diet supplemented with copper did not show the bone mass loss at the axial (fifth lumbar vertebra) or peripheral (femur) level that was evidenced in the ovariectomized group. CONCLUSIONS: The results of the measurement of axial and peripheral bones show that a supplement of copper may have a potential therapeutic application in the treatment and prevention of involutional osteoporosis. 相似文献
82.
Rodríguez-Carreón AA Zúñiga J Hernández-Pacheco G Rodríguez-Pérez JM Pérez-Hernández N Montes de Oca JV Cardiel MH Granados J Vargas-Alarcón G 《Journal of autoimmunity》2005,24(1):63-68
The aim of this study was to determine the frequency and potential relevance of the promoter polymorphisms of the tumor necrosis factor-alpha (TNF-alpha) in the severity of rheumatoid arthritis (RA) in Mexicans. HLA-DR and polymorphisms at positions -238 and -308 of TNF-alpha gene were determined in 137 Mexican RA patients (44 with severe and 93 with non-severe RA) as well as in 169 healthy controls (99 were typed for HLA-DR). We observed an increased frequency of HLA-DR4 in severe RA compared to healthy controls (pC=0.02, OR=2.33). TNF polymorphism analysis showed a significant increased frequency of TNF -238 GG genotype in the whole group of RA patients when compared to healthy controls (pC=0.007, OR=4.71). When the analyses were carried out separately in severe and non-severe RA patients, the increased frequency of -238 GG genotype only was observed in patients with non-severe forms of the disease. Analysis of -308 polymorphism showed increased frequency of -308 T2 (A) allele in severe RA when compared to non-severe disease (pC=0.011, OR=3.29) and to healthy controls (pC=0.002, OR=3.97). The data demonstrate that -308 T2 (A) allele is associated with susceptibility to develop severe RA in Mexicans. This association could be independent from HLA-DR alleles and might be used as a prognostic marker for severe RA. 相似文献
83.
A M Hernández Consuegra Z M La Rosa A Aguirre Roque C Almenares Alarcón M Consuegra Franco 《Revista cubana de enfermería》1990,6(1):27-35
A study is made in the Intensive Care Unit of "José L. Miranda" Provincial Pediatric Teaching Hospital in Santa Clara in order to know the sequence with which the father occupies the place of the mother in the care of hospitalized children. With this objective, 54 male companions are surveyed in the first trimester of 1987. The prevailing occupational profile was that of worker. A higher number of the respondents were between 17 and 25 years of age. The school level of secondary school prevailed among patient companions. Most of them reported no economic inconveniences during the child's disease. The desire to remain at the bedside and the inability of the mother to do so were the major reasons for their stay. The advantages recognized by the nursing personnel in male companions are made known. 相似文献
84.
Hernández AF Gonzalvo MC Gil F Villanueva E Pla A 《Environmental toxicology and pharmacology》1997,3(1):83-86
The effects of three different enzyme-inducing agents (phenobarbital, 3-methylcholanthrene and rifampicin) on plasma and liver microsomal fraction paraoxonase and arylesterase were studied in rats. Although phenobarbital and 3-methylcholanthrene each increased the esterase activities in microsomal fraction, only 3-methylcholanthrene was capable to increase them in plasma. By contrast, the administration of rifampicin decreased both enzyme activities in liver and plasma. The results indicate that at least there exists two esterase activities in rat liver microsomes which hydrolyse both paraoxon and phenylacetate, but only one of them is released into the blood. 相似文献
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A high dietary lipid intake during pregnancy and lactation enhances mammary gland lipid uptake and lipoprotein lipase activity in rats. 总被引:1,自引:0,他引:1
M Del Prado S Villalpando J Gordillo H Hernández-Montes 《The Journal of nutrition》1999,129(8):1574-1578
Rats fed a diet with high fat concentration produce larger amounts of milk with a higher lipid concentration than rats fed a lower fat diet. This investigation was designed to study the relationship between dietary fat intake, mammary gland lipid uptake and lipogenesis in rat dams fed, during pregnancy and lactation, one of two purified diets, with equal energy density, containing 2.5 (LL) or 20 g fat/100 g diet (HL). Milk lipid concentration and fatty acid composition were determined at d 14 of lactation. Mammary gland lipogenesis, lipoprotein lipase (LPL) activity and the uptake of [1-(14)C]triolein by the mammary gland and its transfer to the pups was measured. The intestinal absorption of oral (14)C-lipid, (14)CO(2) production and the amount of (14)C-lipid transferred to the pups (milk clot + pups carcass) were significantly higher in the HL group than in the LL group (P < 0.05). Mammary gland lipogenesis was 75% lower and LPL activity was 30% higher in the HL group (P < 0.05). Medium-chain fatty acids (C6-C14) excretion was 46% lower and that of long-chain fatty acids was 142% (P < 0.001) higher in the HL group than in the LL group. The higher milk lipid excretion in the rats fed a high-fat diet resulted from a larger uptake of dietary lipid by the mammary gland, indicated by a larger transfer of (14)C-lipid to the pups and by a higher LPL activity in the mammary gland. 相似文献
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