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The 2015 Dudrick Research Symposium “Lean Tissue and Protein in Health and Disease: Key Targets and Assessment Strategies” was held on February 16, 2015, at Clinical Nutrition Week in Long Beach, California. The Dudrick Symposium honors the many pivotal and innovative contributions to the development and advancement of parenteral nutrition made by Dr Stanley J. Dudrick, physician scientist, academic leader, and a founding member of the American Society for Parenteral and Enteral Nutrition. As the 2014 recipient of the Dudrick award, Dr Carrie Earthman chaired the symposium and was the first of 3 speakers, followed by Dr Robert Wolfe and Dr Steven Heymsfield. The symposium addressed the importance of lean tissue to health and response to disease and injury, as well as the many opportunities and challenges in its assessment at the bedside. Lean tissue assessment is beneficial to clinical care in chronic and acute care clinical settings, given the strong relationship between lean tissue and outcomes, including functional status. Currently available bioimpedance techniques, including the use of bioimpedance parameters, for lean tissue and nutrition status assessment were presented. The connection between protein requirements and lean tissue was discussed, highlighting the maintenance of lean tissue as one of the most important primary end points by which protein requirements can be estimated. The various tracer techniques to establish protein requirements were presented, emphasizing the importance of practical considerations in research protocols aimed to establish protein requirements. Ultrasound and other new and emerging technologies that may be used for lean tissue assessment were discussed, and areas for future research were highlighted.  相似文献   
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Background: Raw bioimpedance parameters (eg, 50‐kHz phase angle [PA] and 200‐kHz/5‐kHz impedance ratio [IR]) have been investigated as predictors of nutrition status and/or clinical outcomes. However, their validity as prognostic measures depends on the availability of appropriate reference data. Using a large and ethnically diverse data set, we aimed to determine if ethnicity influences these measures and provide expanded bioimpedance reference data for the U.S. population. Methods: The National Health and Nutrition Examination Survey (NHANES) is an ongoing compilation of studies conducted by the U.S. Centers for Disease Control and Prevention designed to monitor nutrition status of the U.S. population. The NHANES data sets analyzed were from the years 1999–2000, 2001–2002, and 2003–2004. Results: Multivariate analysis showed that PA and IR differed by body mass index (BMI), age, sex, and ethnicity (n = 6237; R2 = 41.2%, P < .0001). Suggested reference cut‐points for PA stratified by age decade, ethnicity, and sex are provided. Conclusion: Ethnicity is an important variable that should be accounted for when determining population reference values for PA and IR. We have provided sex‐, ethnicity‐, and age decade–specific reference values from PA for use by future studies in U.S. populations. Interdevice differences are likely to be important contributors to variability across published population‐specific reference data and, where possible, should be evaluated in future research. Ultimately, further validation with physiologically relevant reference measures (eg, dual‐energy x‐ray absorptiometry) is necessary to determine if PA/IR are appropriate bedside tools for the assessment of nutrition status in a clinical population.  相似文献   
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Cardiovascular disease (CVD) is the leading cause of death among women in the United States. Endothelial dysfunction and arterial stiffness increase with advancing age and are early predictors of future CVD outcomes. We designed the Modulating Oxidative Stress and Inflammation in Elders (MOXIE) study to examine the effects of 100% watermelon juice as a “food-first” intervention to reduce CVD risk among African American (AA) and European American (EA) women aged 55–69 years. Vascular dysfunction is more pronounced in AA compared to EA women due in part to lower nitric oxide bioavailability caused by higher oxidative stress. However, bioactive compounds in watermelon may improve vascular function by increasing nitric oxide bioavailability and antioxidant capacity. This trial will use a randomized, placebo-controlled, crossover design to investigate the potential of 100% watermelon juice to positively impact various robust measures of vascular function as well as serum biomarkers of oxidative stress and antioxidant capacity. This nutrition intervention and its unique methodology to examine both clinical and mechanistic outcomes are described in this article.  相似文献   
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目的:研究立体定向伽玛刀对海绵窦区脑膜瘤治疗效果。方法:对142例进行治疗,其中男52例,女90例。平均年龄49.5岁。对107例连续随访研究4 ̄98个月。并对神经状况和瘤体变化作出评价。结果:无死亡率。肿瘤体积缩小52例,保持稳定50例,体积增大5例,新的颅神经损害发生率为5.6%。结论:伽玛刀对适当病例进行治疗是一种疗效肯定、并发症极少的有效方法。  相似文献   
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The degree of immunodeficiency associated with deficiency of adenosine deaminase (ADA) is variable. Most patients are infants with severe combined immunodeficiency (SCID), but in about 20 percent immune dysfunction becomes manifest later in childhood ("delayed-onset"); several patients with "late" or "adult" onset of immune dysfunction have been diagnosed at 15–39 years. Over 40 ADA gene mutations have thus far been identified. To better define the genotype-phenotype relationship, we report 7 novel ADA mutations, including 5 missense mutations (G74C, V129M, G140E, R149W, Q199P) and two short deletions (462delG, E337del). These were identifed among 7 patients (3 with SCID and 4 with delayed-onset). A homozygote for 462delG had SCID, whereas patients homozygous or heterozygous for V129M had delayed-onset. Two other delayed-onset patients, one heterozygous for G74C and the other for Q199P, each had a second allele carrying the previously reported "severe" mutation G216R. These findings are consistent with previous observations suggesting that, in general, SCID occurs when both alleles eliminate ADA function, and a milder phenotype when at least one allele can supply a low level of function. Hum Mutat 11:482, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
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Production of prostaglandins is a critical step in transducing immune stimuli into central nervous system (CNS) responses, but the cellular source of prostaglandins responsible for CNS signalling is unknown. Cyclooxygenase catalyzes the rate-limiting step in the synthesis of prostaglandins and exists in two isoforms. Regulation of the inducible isoform, cyclooxygenase 2, is thought to play a key role in the brain's response to acute inflammatory stimuli. In this paper, we report that intravenous lipopolysaccharide (LPS or endotoxin) induces cyclooxygenase 2-like immunoreactivity in cells closely associated with brain blood vessels and in cells in the meninges. Neuronal staining was not noticeably altered or induced in any brain region by endotoxin challenge. Furthermore, many of the cells also were stained with a perivascular microglial/macrophage-specific antibody, indicating that intravenous LPS induces cyclooxygenase in perivascular microglia along blood vessels and in meningeal macrophages at the edge of the brain. These findings suggest that perivascular microglia and meningeal macrophages throughout the brain may be the cellular source of prostaglandins following systemic immune challenge. We hypothesize that distinct components of the CNS response to immune system activation may be mediated by prostaglandins produced at specific intracranial sites such as the preoptic area (altered sleep and thermoregulation), medulla (adrenal corticosteroid response), and cerebral cortex (headache and encephalopathy). J. Comp. Neurol. 381:119-129, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
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