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51.
Aim: To determine the difference in the levels of nitrites in induced sputum of children with cystic fibrosis (CF) and controls. Furthermore, to evaluate the association between induced sputum nitrites and lung function in children with CF. Methods: Nitrites, cell differentials, white blood cell count, were estimated in induced sputum of 20 children with CF and 10 age‐matched healthy controls. Nitrites in induced sputum samples were measured using the Greiss assay. Lung function was ascertained by spirometry. Results: We observed high levels of nitrites in CF (184.8 ± 11.07 μM/L) versus controls (56.4 ± 5.7 μM/L) (p < 0.01). A positive correlation between neturophil percent and nitrites, white blood cell count and nitrites (p < 0.05) in children with CF was observed. Sputum nitrites correlated negatively with FEV1 (p < 0.05) in children with CF. Conclusion: Induced sputum nitrite could serve as a useful non invasive marker for assessing the degree of inflammation in the airways of children with CF.  相似文献   
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The international boundaries to medical education are becoming less marked as new technologies such as multiuser videoconferencing are developed and become more accessible to help bridge the communication gaps. The Global Educational Toxicology Uniting Project (GETUP) is aimed at connecting clinicians in countries with established clinical toxicology services to clinicians in countries without clinical toxicologists around the globe. Centers that manage or consult on toxicology cases were registered through the American College of Medical Toxicology website via Survey Monkey®. Data was analyzed retrospectively from February 2014 to January 2015. Google hangouts® was used as the main conferencing software, but some sites preferred the use of Skype®. Registration data included contact details and toxicology background and qualifications. Thirty sites in 19 different countries in Australasia, Europe, Africa, and America were registered. Twenty-eight (93 %) sites were located in a major urban center, one (3.5 %) site in a major rural center and one (3.5 %) a private practice. Expectations of GETUP included sharing toxicology cases and education (30, 100 % of sites), assistance with toxicology management guidelines (2, 7 %), assistance with providing a toxicology teaching curriculum in languages other than English (2, 7 %), and managing toxicology presentations in resource-poor settings, international collaboration, and toxicovigilance (2 sites, 7 %). Twenty-two conferences were performed during the first 12 months with a mean of 3 cases per conference. GETUP has connected countries and clinical units with and without toxicology services and will provide a platform to improve international collaboration in clinical toxicology.  相似文献   
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Chronic periodontitis is a complex infection initiated by gram-negative bacteria which destroy the supporting structures of the tooth. Recently, it has been recognized that it is the host response to bacterial infection which causes greater destruction of the connective tissue elements, periodontal ligament and alveolar bone in periodontitis. This has led to the development of various host modulating approaches to target cells and their destructive mediators involved in tissue degradation. Chemically modified tetracyclines (CMTs) are derivatives of tetracycline group of drugs which lack antimicrobial action but have potent host modulating affects. They inhibit pathologically elevated matrix metal loproteinases, pro-inflammtory cytokines and other destructive mediators. Bone resorption is also suppressed due to their combined anti-proteinase and apoptotic affects on osteoblasts and osteoclasts, respectively. Development of resistant bacteria and gastrointestinal toxicity seen with parent tetracyclines is not produced by CMTs. Hence, CMTs are viewed as potential therapeutic agents in the management of chronic diseases like periodontitis that involve destruction of connective tissue and bone.  相似文献   
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Elevated arsenic (As) concentrations in urban soils with prolonged arsenical pesticide application history have increased the risk associated with accidental hand-to-mouth soil ingestion by children. Earlier work by the authors suggested that the conservative statement of 100% As bioaccessibility in soils was not valid for a set of acidic soils incubated with sodium arsenate. In this study, two alkaline Texas soils incubated with a commonly used As pesticide (sodium arsenate) were evaluated for their potential in reducing soil As bioaccessibility. The objective of this study was to evaluate the effects of incubation time and As load on soil As fractionation and bioaccessibility. Soils were subjected to a sequential As fractionation scheme, and bioaccessible As was quantified using an in vitro stomach phase test. Results showed a reduction in the water-soluble As fraction with incubation time (after 4 months), which remained unchanged after 12 months. This reduction with time was accompanied by an increase in the NaOH- and H2SO4-extractable As fractions, suggesting As sorption by amorphous Fe/Al hydroxides and/or Ca/Mg compounds, respectively. Organic/sulfides-bound As increased with incubation time after 12 months but not after 4 months of incubation. The aging effect was also observed with the amount of bioaccessible As at all As loads, showing significant positive correlations with the water-extractable and exchangeable As fractions. Bioaccessible As concentrations even after 12 months of incubation were not significantly reduced, suggesting that natural attenuation might prove inadequate to control As bioaccessibility in these alkaline soils.  相似文献   
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Lower relative rates of energy expenditure (EE), increased energetic efficiency, and altered fuel utilization purportedly associated with obesity have not been demonstrated indisputably in overweight children. We hypothesized that differences in energy metabolism between nonoverweight and overweight children are attributable to differences in body size and composition, circulating thyroid hormones, sympathetic nervous system, and adrenomedullary activity. A total of 836 Hispanic children, 5-19 y old, participated in 24-h calorimetry, anthropometric, and dual-energy X-ray absorptiometry measurements. Biochemistries were determined by standard techniques. Absolute total EE (TEE) and its components (sleep EE, basal EE, sedentary EE, cycling EE, walking EE, activity EE, nonexercising activity thermogenesis) were higher in overweight children (P = 0.001). Net mechanical energetic efficiency of cycling was lower in overweight children (P = 0.001). Adjusting for body size and composition accounted for differences in TEE, its components, and energetic efficiency. Net carbohydrate and fat utilization did not differ between groups. TEE was independently influenced by sex, Tanner stage, fat free mass, fat mass (FM), fasting serum nonesterified fatty acids (NEFA), leptin, free thyroxine, triiodothyronine, and 24-h urinary norepinephrine and epinephrine. Fat utilization was independently associated with age2, sex, FM, fasting serum NEFA, triacylglycerol, adiponectin, leptin, total thyroxine, and free triiodothyronine. Higher EE in overweight children was largely explained by differences in body size and composition, with minor contributions of thyroid and sympathoadrenal systems. Alterations in EE, energetic efficiency, and substrate utilization were not evident in the overweight children.  相似文献   
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We evaluated the colorimetric polymerase chain reaction (PCR)-based method for the detection and differentiation of Entamoeba spp. and compared the efficacy of E. histolytica-specific antigen detection in faeces with the detection of specific antibodies to E. histolytica-specific antigen in faeces, by enzyme-linked immunosorbent assay. Faecal samples were obtained from patients attending hospital in Chandigarh, India, from March 2001 to February 2002. The PCR-based colorimetric method was found to be the most sensitive (100%) and it could differentiate between pathogenic and non-pathogenic Entamoeba spp. The present study also emphasized that the antigen detection system may prove to be a better diagnostic tool than the antibody detection system in endemic areas.  相似文献   
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- AIMS: Turner syndrome (TS) is a sex chromosome aneuploidy that occurs as a result of a non-disjunctional error in meiosis I or anaphase lag; however, the aetiology of this disorder remains unknown. Anecdotal evidence suggests that paternal alcoholism may play an unidentified role in the aetiology of TS. Accordingly, the primary objective of this study was to determine the potential association between paternal alcohol exposure and TS. METHODS: The questionnaire was designed to solicit information about the parents' health and lifestyle habits occurring 1 year prior to and throughout the pregnancy of their daughter with TS. Alcohol dependence was assessed by the Brief Michigan Alcohol Screening Test (BMAST). The study population was solicited from the Turner's Syndrome Society of Canada and included any parent(s) having a child with TS who was of any age. Two hundred and twelve families completed and returned the survey. RESULTS: This provided a response rate of 86.5%. Six of the fathers (3.6%; n = 166) and six of the mothers (3.6%; n = 165) had scores of 5 or more on the BMAST (scores of 5+ are considered to be in the 'alcoholic range'). This is considerably lower than the population norm of 9.5%. CONCLUSIONS: Our study has suggested there is no association between paternal or maternal alcohol consumption and TS.  相似文献   
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