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Secondary hyperparathyroidism contributes to post-transplant CKD mineral and bone disorder. Paricalcitol, a selective vitamin D receptor activator, decreased serum parathyroid hormone levels and proteinuria in patients with secondary hyperparathyroidism. This single-center, prospective, randomized, crossover, open-label study compared the effect of 6-month treatment with paricalcitol (1 μg/d for 3 months and then uptitrated to 2 µg/d if tolerated) or nonparicalcitol therapy on serum parathyroid hormone levels (primary outcome), mineral metabolism, and proteinuria in 43 consenting recipients of renal transplants with secondary hyperparathyroidism. Participants were randomized 1:1 according to a computer-generated sequence. Compared with baseline, median (interquartile range) serum parathyroid hormone levels significantly declined on paricalcitol from 115.6 (94.8–152.0) to 63.3 (52.0–79.7) pg/ml (P<0.001) but not on nonparicalcitol therapy. At 6 months, levels significantly differed between treatments (P<0.001 by analysis of covariance). Serum bone-specific alkaline phosphatase and osteocalcin decreased on paricalcitol therapy only and significantly differed between treatments at 6 months (P<0.001 for all comparisons). At 6 months, urinary deoxypyridinoline-to-creatinine ratio and 24-hour proteinuria level decreased only on paricalcitol (P<0.05). L3 and L4 vertebral mineral bone density, assessed by dual-energy x-ray absorption, significantly improved with paricalcitol at 6 months (P<0.05 for both densities). Paricalcitol was well tolerated. Overall, 6-month paricalcitol supplementation reduced parathyroid hormone levels and proteinuria, attenuated bone remodeling and mineral loss, and reduced eGFR in renal transplant recipients with secondary hyperparathyroidism. Long-term studies are needed to monitor directly measured GFR, ensure that the bone remodeling and mineral effects are sustained, and determine if the reduction in proteinuria improves renal and cardiovascular outcomes.  相似文献   
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Objective To investigate how North American thyroidologists assess and treat amiodarone‐induced thyrotoxicosis (AIT) and to compare the results with those of the same questionnaire‐based survey previously carried out among European thyroidologists. Design Members of the American Thyroid Association (ATA) with clinical interests were sent by e‐mail a questionnaire on the diagnosis and management of AIT, 115 responses were received from the United States and Canada, representing about one‐third of ATA members with clinical interests. Results The majority of respondents (91%vs. 68% in Europe, P < 0·05) see < 10 new cases of AIT per year, and AIT seems less frequent than amiodarone‐induced hypothyroidism (AIH) in North America (34% and 66% of amiodarone‐induced thyroid dysfunction, respectively, vs. 75% and 25%, respectively, in Europe, P < 0·001). When AIT is suspected, in North America hormonal assessment is mostly based on serum free T4 (FT4) and TSH measurements, while serum free T3 (FT3) determination is requested less frequently than in Europe; thyroid autoimmunity is included in the initial assessment less than in Europe. Most commonly used additional diagnostic procedures include, as in Europe, thyroid colour‐flow Doppler sonography, and to a lesser extent, thyroid radioactive iodine uptake and scan, but Europeans tend to request multiple tests more than North Americans. Withdrawal of amiodarone is more often considered unnecessary by North American thyroidologists (21%vs. 10% in Europe in type 1 AIT, P < 0·05, 34%vs. 20% in type 2 AIT, P < 0·05). In type 1 AIT thionamides represent the treatment of choice for North Americans as well as for Europeans, but the former use them as monotherapy in 65%vs. 51% of Europeans (P < 0·05) who more often consider potassium perchlorate as an useful addition (31%vs. 15% of North Americans, P < 0·01). Glucocorticoids are the selected treatment for type 2 AIT, alone (62%vs. 46% in Europe, P < 0·05) or in association with thionamides (16%vs. 25% in Europe, P = NS). After restoration of euthyroidism, thyroid ablation in the absence of recurrent thyrotoxicosis is recommended in type 1 AIT less frequently by North Americans. If amiodarone therapy needs to be reinstituted, prophylactic thyroid ablation is advised by 76% in type 1 AIT, while a ‘wait‐and‐see’ strategy is adopted by 61% in type 2 AIT, similar to behaviour of European thyroidologists. Conclusion Similarities and differences exist between expert North American and European thyroidologists concerning the diagnosis and management of AIT. While differences reflect the frequent uncertainty of the underlying mechanism leading to AIT, similarities may represent the basis to refine the diagnostic criteria and to improve the therapeutic outcomes of this challenging clinical situation.  相似文献   
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The route of infection can profoundly affect both the progression and outcome of disease. We investigated differences in Drosophila melanogaster defense against infection after bacterial inoculation into two sites—the abdomen and the thorax. Thorax inoculation results in increased bacterial proliferation and causes high mortality within the first few days of infection. In contrast, abdomen inoculation results in minimal mortality and lower bacterial loads than thorax inoculation. Inoculation into either site causes systemic infection. Differences in mortality and bacterial load are due to injury of the thorax and can be recapitulated by abdominal inoculation coupled with aseptic wounding of the thorax. This altered resistance appears to be independent of classical immune pathways and opens new avenues of research on the role of injury during defense against infection.  相似文献   
55.
The synthesis of deflazacort (DFZ) and a preliminary evaluation of its microbial activity against the human pathogens Acinetobacter baumannii and Staphylococcus aureus is herein reported. While DFZ is inactive, one of its synthetic precursors showed a strong antibacterial activity against both Gram-negative and -positive bacteria.

Synthesis of deflazacort: unexpected antibacterial activity of its epoxide synthetic precursor.  相似文献   
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Weight loss maintenance is a major challenge for obesity treatment. Weight control registries can be useful in identifying psychological and behavioural factors that could contribute to better long‐term success. The objective of this study is to describe the existing weight control registries and their participants and identify correlates of weight loss maintenance. A comprehensive search of peer‐reviewed articles published until November 2018 was conducted in PubMed, Web of Science, and Scopus. Studies that reported results from weight control registries were considered. Fifty‐two articles, corresponding to five registries (the United States, Portugal, Germany, Finland, and Greece), were included. Registries differed in inclusion criteria and procedures. Of 51 identified weight loss and maintenance strategies, grouped in 14 domains of the Oxford Food and Activity Behaviors taxonomy, the following were the most frequently reported: having healthy foods available at home, regular breakfast intake, increasing vegetable consumption, decreasing sugary and fatty foods, limiting certain foods, and reducing fat in meals. Increased physical activity was the most consistent positive correlate of weight loss maintenance. To our knowledge, this is the first systematic review of information about successful weight loss maintenance obtained from weight control registries. Key common influential characteristics of success were identified, which can inform future prospective studies and weight management initiatives.  相似文献   
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Our goal was to determine whether genetic variation at genes affecting statin metabolism or targets of statin therapy would influence low density lipoprotein (LDL) cholesterol lowering with pravastatin, baseline heart disease, or cardiac endpoints on trial. We examined associations of single nucleotide polymorphisms (SNPs) at the liver X receptor alpha (LXRA, rs12221497), and the solute carrier organic anion transporter (SLCO1B1, rs4149056 and rs2306283) gene loci with these variables. We studied 5411 participants in PROSPER (PROspective Study of Pravastatin in the Elderly at Risk) (mean age 75.3 years), who had been randomized to pravastatin 40 mg/day or placebo and were followed for a mean of 3.2 years. No relationships between genetic variation at the LXRA gene locus with statin induced LDL lowering response or other parameters were noted. Both the SLCO1B1 rs4149056 (valine for alanine at 174) and the rs2306283 (asparagine for aspartic acid at 130) SNPs affect the amino acid sequence of the SLCO1B1 gene product. No effect of the rs2306283 SNP on any of the variables was noted. However the presence of the rs4149056 SNP was associated with significantly less LDL cholesterol lowering response to pravastatin (wildtype, 71.5% of the population, -37.0%; heterozygotes, 25.8% of the population, -36.0%; and homozygotes, 2.7% of the population, -31.8%, p=0.003 at 6 months, and p=0.022 at 12 months). Our data indicate that the presence of the rs4149056 non-synonymous SNP at the SLCO1B1 gene locus can significantly decrease the pravastatin induced LDL cholesterol lowering response.  相似文献   
60.
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