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81.
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Three children were observed to have extensive liver injury following protracted seizures. Two recovered with supportive care and one died from central nervous system complications. When first measured, the levels of aminotransferases were minimally elevated, but they increased to 250 to 8,000 times normal within 12 to 24 h after the seizure episode. They fell to near normal over the next 8 to 11 days in the survivors, and to one sixth of the peak level by 4 days in the patients who died. A percutaneous liver biopsy from one child demonstrated centrolobular necrosis consistent with severe ischemic injury. Common causes for liver dysfunction, including viral hepatitis, drug hepatitis, and Reye syndrome, were excluded on clinical, serologic, and histologic grounds. We reason that hepatic injury resulted from ischemia. We speculate that prior treatment with anticonvulsants, which are capable of inducing mixed-function oxidases in the liver, aggravated the ischemia-reperfusion injury by increasing the production of reactive oxygen intermediates and reducing cytoprotective mechanisms. Prevention of such injury should be directed toward control of seizures and early respiratory support when seizures occur, not restructuring medication regimens.  相似文献   
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BACKGROUND: As the main mineral reservoir, bone acts as a calcium (Ca) and phosphate buffering system. Accordingly, phosphate removal by haemodialysis (HD) might be theoretically influenced by bone turnover, as well as by the interaction of regulatory molecules, such as PTH and osteoprotegerin (OPG). The present study investigated the relationship between these variables and phosphate removal by HD. METHODS: Blood samples for serum Ca, phosphate, bicarbonate, intact PTH, PTH (1-84), bone alkaline phosphatase, tartrate-resistant acid phosphatase 5b, OPG and receptor activator of nuclear factor-kappaB ligand (RANKL) were obtained in 28 HD patients. Phosphate removal was measured by a continuous collection of the dialysate. RESULTS: Pre-dialysis serum phosphate concentration is the critical factor in determining dialytic phosphate removal. However, multiple regression analysis reveals that phosphate removal is better explained by a combination of factors than by phosphate concentration alone. In this model, the PTH/OPG ratio is an additional positive factor, whereas age and vitamin D treatment are negative factors. Patients with pre-HD bicarbonate higher than 20 mEq/l had higher serum phosphate and, accordingly, higher phosphate removal; of interest, these individuals also have significant differences in RANKL/OPG. Mean (SD) OPG levels were significantly higher than that in the healthy population (16.2 (12.5) pmol/l; these values correlated with age (r = 0.4, P<0.04). Mean serum RANKL (1.03 (1.02) pmol/l) was within the range of normal individuals. CONCLUSIONS: Dialytic phosphate removal has a crucial, direct relationship with pre-HD plasma phosphate levels. However, the phenomenon of phosphate removal is more precisely explained using a more complex relationship, defined by the interaction between serum phosphate, PTH/OPG, age and vitamin D administration. Serum RANKL levels are first reported in HD patients, and are not different from the normal population.  相似文献   
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Gender differences in the apolipoprotein (apo) E genotype effect on plasma lipid levels reported in adults have also been found in pre-pubertal children. In adults, the difference seems to be due to the influence of sexual hormones. The reason why this difference exits between pre-pubertal girls and boys, for whom those sexual hormones are not different, is unclear. However, there is an important difference in Dehydroepiandrosterone-sulfate (DHEA-S) levels between pre-pubertal boys and girls. To evaluate the influence of DHEA-S on apo E genetic determinants of plasma lipids levels in pre-pubertal children we measured plasma DHEA-S in 1045 healthy children (534 males and 511 females) 6 to 8 years old in which a different apoE influence on lipid levels had been reported between girls and boys. Our observations demonstrate that the extent of the lipid increasing or decreasing effects associated with each allele were modulated by DHEA-S. DHEA-S increases the hypolipemic effect of the epsilon2 allele and decreases the hyperlipemic effect of the epsilon4 allele. In conclusion, the interaction of apo E genotype and DHEA-S may represent a critical determinant of TC, LDL-C and apo B levels in children at the prepuberal age.  相似文献   
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To evaluate the influence of birth weight on apolipoprotein (apo) E genetic determinants of plasma lipids levels in prepubertal children we studied 933 healthy children (491 males and 442 females) 6 to 8 years old (mean age of 6.7 y), whose weight was recorded at birth. Plasma lipid and apolipoprotein concentrations and apo E genotypes were determined. We observed a greater effect of the apo E polymorphism on total cholesterol (TC), LDL-cholesterol (LDL-C) and especially apo B levels in children with birth weight in the lower tertile compared with those with birth weights in higher tertiles. Taking the epsilon3 allele homozygosity as reference, in boys with birth weights in the low tertile the overall lowering effect of the epsilon2 allele on TC, LDL-C and apo B was greater (10.5% (p < 0.01), 20.2% (p < 0.01) and 18.8% (p < 0.01), respectively) than in those in the highest tertile (5.6% on TC, 10.3% on LDL-C and 12.6% (p < 0.01) on apo B). A similar trend in this effect between tertiles of birth weight was also observed in girls. For both sexes, linear regression analysis demonstrates a positive and significant interaction between birth weight and epsilon2, which may explain the fact that the decrease in TC, LDL-C and apo B associated with the epsilon2 allele is more marked the lower the birth weight. Taking into account the prevalence of apo E polymorphism, and that appears to be the main genetic factor affecting plasma lipids, the interaction of apo E genotype and birth weight could be an important determinant of TC, LDL-C and apo B levels, and, as a consequence, of atherosclerosis.  相似文献   
88.
This article reports cross-sectional data from a total of 1048 children, 6 to 8 years of age, categorized by presence or absence of obesity, who participated in a voluntary survey of cardiovascular risk factors in Spain over the period of 1998 to 2000, to establish the relationship between obesity and its metabolic consequences at this age. The prevalence of obesity and overweight were 9.4% and 15.7%, respectively, in boys and 10.5% and 18.0%, respectively, in girls. We observed that, in both sexes, obese children had higher triglycerides and lower high-density lipoprotein-cholesterol levels than non-obese children. No differences were found in plasma glucose or low-density lipoprotein-cholesterol levels between normal and obese children. However, we observed that insulin levels and the homeostasis model assessment for insulin resistance were significantly (p<0.001) higher in obese children of both sexes but that free fatty acid levels were lower in obese children than in nonobese children, with a statistical significance in girls (0.72+/-0.30 vs. 0.61+/-0.16 mEq/liter). In summary, our survey found some metabolic consequences of obesity similar to those found in adults (elevated triglycerides, insulin, and the homeostasis model assessment for insulin resistance, and lower high-density lipoprotein-cholesterol). However, other features (glucose, total cholesterol, low-density lipoprotein-cholesterol, and free fatty acid levels) were found to behave differently, indicating that the association of obesity with risk factors seems to change as the children age and may depend on the chronology of sexual maturation.  相似文献   
89.
This positioning document, sponsored by the Asociación Española de Gastroenterología, the Sociedad Española de Endoscopia Digestiva and the Sociedad Española de Anatomía Patológica, aims to establish recommendations for the screening of gastric cancer (GC) in low incidence populations, such as the Spanish. To establish the quality of the evidence and the levels of recommendation, we used the methodology based on the GRADE system (Grading of Recommendations Assessment, Development and Evaluation). We obtained a consensus among experts using a Delphi method. The document evaluates screening in the general population, individuals with relatives with GC and subjects with GC precursor lesions (GCPL). The goal of the interventions should be to reduce GC related mortality. We recommend the use of the OLGIM classification and determine the intestinal metaplasia (IM) subtype in the evaluation of GCPL. We do not recommend to establish endoscopic mass screening for GC or Helicobacter pylori. However, the document strongly recommends to treat H. pylori if the infection is detected, and the investigation and treatment in individuals with a family history of GC or with GCPL. Instead, we recommend against the use of serological tests to detect GCPL. Endoscopic screening is suggested only in individuals that meet familial GC criteria. As for individuals with GCPL, endoscopic surveillance is only suggested in extensive IM associated with additional risk factors (incomplete IM and/or a family history of GC), after resection of dysplastic lesions or in patients with dysplasia without visible lesion after a high quality gastroscopy with chromoendoscopy.  相似文献   
90.
This paper focuses on the effect of the drill geometry on the drilling of woven Carbon Fiber Reinforced Polymer composite (CFRPs). Although different geometrical effects can be considered in drilling CFRPs, the present work focuses on the influence of point angle and wear because they are the important factors influencing hole quality and machining forces. Surface quality was evaluated in terms of delamination and superficial defects. Three different point angles were tested representative of the geometries commonly used in the industry. Two wear modes were considered, being representative of the wear patterns commonly observed when drilling CFRPs: flank wear and honed cutting edge. It was found that the crossed influence of the point angle and wear were significant to the thrust force. Delamination at the hole entry and exit showed opposite trends with the change of geometry. Also, cutting parameters were checked showing the feed’s dominant influence on surface damage.  相似文献   
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