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81.
BACKGROUND: Little is known about the combined effect of micronutrients and essential fatty acids on cognitive function in school-aged children. OBJECTIVE: We assessed the effect of micronutrients, long-chain n-3 fatty acids, or both on indicators of cognitive performance in well-nourished and marginally nourished school-aged children. DESIGN: Two 2-by-2 factorial randomized controlled double-blind trials were performed home-based in Adelaide, South Australia, and at 6 primary schools in Jakarta, Indonesia. A total of 396 children (aged 6-10 y) in Australia and 384 children in Indonesia were randomly allocated to receive a drink with a micronutrient mix (iron, zinc, folate, and vitamins A, B-6, B-12, and C), with docosahexanoic acid (DHA, 88 mg/d) and eicosapentaenoic acid (EPA, 22 mg/d), or with both or placebo 6 d/wk for 12 mo. Biochemical indicators were determined at baseline and 12 mo. Cognitive performance was measured at baseline, 6 mo, and 12 mo. RESULTS: The micronutrient treatment significantly improved plasma micronutrient concentrations in Australian and Indonesian children. DHA+EPA treatment increased plasma DHA and total plasma n-3 fatty acids in both countries. The micronutrient treatment resulted in significant increases in scores on tests representing verbal learning and memory in Australia (estimated effect size: 0.23; 95% CI: 0.01, 0.46). A similar effect was observed among Indonesian girls (estimated effect size: 0.32; 95% CI: -0.01, 0.64). No effects were found on tests measuring general intelligence or attention. No effects of DHA+EPA on the factors of cognitive tests were observed. CONCLUSION: In well-nourished school-aged children, fortification with multiple micronutrients can result in improvements in verbal learning and memory.  相似文献   
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Serum gamma-glutamyl transferase (GGT) activity is a marker of liver disease which is also prospectively associated with the risk of all-cause mortality, cardiovascular disease, type 2 diabetes and cancers. We have discovered novel loci affecting GGT in a genome-wide association study (rs1497406 in an intergenic region of chromosome 1, P = 3.9 × 10(-8); rs944002 in C14orf73 on chromosome 14, P = 4.7 × 10(-13); rs340005 in RORA on chromosome 15, P = 2.4 × 10(-8)), and a highly significant heterogeneity between adult and adolescent results at the GGT1 locus on chromosome 22 (maximum P(HET) = 5.6 × 10(-12) at rs6519520). Pathway analysis of significant and suggestive single-nucleotide polymorphism associations showed significant overlap between genes affecting GGT and those affecting common metabolic and inflammatory diseases, and identified the hepatic nuclear factor (HNF) family as controllers of a network of genes affecting GGT. Our results reinforce the disease associations of GGT and demonstrate that control by the GGT1 locus varies with age.  相似文献   
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Serum butyrylcholinesterase (BCHE) activity is associated with obesity, blood pressure and biomarkers of cardiovascular and diabetes risk. We have conducted a genome-wide association scan to discover genetic variants affecting BCHE activity, and to clarify whether the associations between BCHE activity and cardiometabolic risk factors are caused by variation in BCHE or whether BCHE variation is secondary to the metabolic abnormalities. We measured serum BCHE in adolescents and adults from three cohorts of Australian twin and family studies. The genotypes from ~2.4 million single-nucleotide polymorphisms (SNPs) were available in 8791 participants with BCHE measurements. We detected significant associations with BCHE activity at three independent groups of SNPs at the BCHE locus (P = 5.8 × 10(-262), 7.8 × 10(-47), 2.9 × 10(-12)) and at four other loci: RNPEP (P = 9.4 × 10(-16)), RAPH1-ABI2 (P = 4.1 × 10(-18)), UGT1A1 (P = 4.0 × 10(-8)) and an intergenic region on chromosome 8 (P = 1.4 × 10(-8)). These loci affecting BCHE activity were not associated with metabolic risk factors. On the other hand, SNPs in genes previously associated with metabolic risk had effects on BCHE activity more often than can be explained by chance. In particular, SNPs within FTO and GCKR were associated with BCHE activity, but their effects were partly mediated by body mass index and triglycerides, respectively. We conclude that variation in BCHE activity is due to multiple variants across the spectrum from uncommon/large effect to common/small effect, and partly results from (rather than causes) metabolic abnormalities.  相似文献   
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The Salutogenesis theory and its essential component, the sense of coherence (SOC) is an epigenetic concept. The SOC was defined as a 'way of being in the world'. As such it is most important that one's SOC will be intact for healthy mental status. Collisions between western and non-western cultures might interfere in the process of psychiatric and psychotherapeutic treatment. This review demonstrates the importance of a culture-sensitive approach and therapy and the usefulness of specific culture-sensitive services for certain non-western populations. We illustrate this approach by giving the example of the unique ways of treatment carried out among the Bedouin of the Negev region of Israel.  相似文献   
86.

Background

Development of an artificial pancreas based on an automatic closed-loop algorithm that uses a subcutaneous insulin pump and continuous glucose sensor is a goal for biomedical engineering research. However, closing the loop for the artificial pancreas still presents many challenges, including model identification and design of a control algorithm that will keep the type 1 diabetes mellitus subject in normoglycemia for the longest duration and under maximal safety considerations.

Method

An artificial pancreatic β-cell based on zone model predictive control (zone-MPC) that is tuned automatically has been evaluated on the University of Virginia/University of Padova Food and Drug Administration-accepted metabolic simulator. Zone-MPC is applied when a fixed set point is not defined and the control variable objective can be expressed as a zone. Because euglycemia is usually defined as a range, zone-MPC is a natural control strategy for the artificial pancreatic β-cell.Clinical data usually include discrete information about insulin delivery and meals, which can be used to generate personalized models. It is argued that mapping clinical insulin administration and meal history through two different second-order transfer functions improves the identification accuracy of these models. Moreover, using mapped insulin as an additional state in zone-MPC enriches information about past control moves, thereby reducing the probability of overdosing. In this study, zone-MPC is tested in three different modes using unannounced and announced meals at their nominal value and with 40% uncertainty. Ten adult in silico subjects were evaluated following a scenario of mixed meals with 75, 75, and 50 grams of carbohydrates (CHOs) consumed at 7 am, 1 pm, and 8 pm, respectively. Zone-MPC results are compared to those of the “optimal” open-loop preadjusted treatment.

Results

Zone-MPC succeeds in maintaining glycemic responses closer to euglycemia compared to the “optimal” open-loop treatment in te three different modes with and without meal announcement. In the face of meal uncertainty, announced zone-MPC presented only marginally improved results over unannounced zone-MPC. When considering user error in CHO estimation and the need to interact with the system, unannounced zone-MPC is an appealing alternative.

Conclusions

Zone-MPC reduces the variability of control moves over fixed set point control without the need to detune the controller. This strategy gives zone-MPC the ability to act quickly when needed and reduce unnecessary control moves in the euglycemic range.  相似文献   
87.
This study describes a family of hollow nanoscale constructs able to display a large and reversible change in size, within a narrow temperature interval. These thermoresponsive nanostructures are generated by crosslinking functionalized amphiphilic molecules, such as poly(ethylene oxide)–poly(propylene oxide)–poly(ethylene oxide) (PEO–PPO–PEO) triblocks, while constrained to their particular micellar configuration. This contribution focuses on the generation of these supramolecular architectures, by intra-micellarly crosslinking PEO–PPO–PEO dimethacrylate amphiphiles, and investigates their temperature-dependent dimensional behavior. Spherical nanoshells displaying a 200 nm diameter at 15 °C, shrink sharply around 28 °C, generating a compact structure of approximately 40 nm at body temperature. Thermoresponsive nanotubes were created by generating them from rod-like micelles at higher temperatures. By varying the composition of the triblock, the transition temperature can be fine tuned, from around 25 °C to slightly above body temperature. Also, the nanoshells were rendered biodegradable by incorporating aliphatic oligoesters into their structure. Numerous applications for these nanostructures are foreseen in various biomedical areas, such as in drug and gene delivery, in the tissue engineering and in the biosensors field.  相似文献   
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INTRODUCTION: Restenosis remains a problem even after stent implantation. An important breakthrough could be the use of graft stents, functioning as a mechanical barrier between the blood flow and the vessel wall, and possibly inducing less restenosis by more limited hyperplasia and minimal transgraft tissue penetration. OBJECTIVE: To assess the acute and 6 months clinical, angiographic and IVUS results of a new balloon expandable coronary polytetrafluoroethylene (PTFE) graft stent (Jomed). METHOD: Ten patients with a short (< or = 15 mm length) de novo proximal stenosis in a large (> or = 3 mm diameter) coronary artery were treated by elective implantation of a graft stent (19 mm stent, 15 mm graft). Clinical assessment, quantitative coronary angiography (QCA) and intracoronary ultrasound (IVUS) were performed before, immediately after and 6 months after implantation. A stress test was also done at 6 months. RESULTS : The coronary arteries treated were: RCA in 7 patients, LCX in 2 patients, LAD in 1 patient. Mean balloon size was 3.7 mm diameter, and mean inflation pressure was 18 atm (min. 12, max. 23). Additional stenting was needed in 3 patients. Two patients showed a minimal rise in CK (< 250 IU/l) and 1 patient needed a transfusion. No patient experienced a (sub)acute nor late thrombosis. As shown in the table, no restenosis was seen in the body of the graft stent. In 2 patients a restenosis was detected in the proximal and/or distal parts of the stent which are not covered by the graft. In 1 patient a restenosis was found outside the stent. All patients remained asymptomatic with a negative stress test at 6 months follow-up (FU). [table in text] CONCLUSIONS: A graft stent could indeed reduce the restenosis rate after stenting, in the part of the stent covered by the graft, but the uncovered distal and proximal parts are the weak points in this type of stent. For this reason, technical ameliorations in the construction of this graft stent are needed, e.g. a complete coverage of the stent by the PTFE graft and less rigidity of the stent causing reduced vessel trauma at the edges of the stent during implantation.  相似文献   
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