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661.
Effectiveness and pitfalls of percutaneous transpedicle biopsy of the spine   总被引:3,自引:0,他引:3  
Seventy-one percutaneous transpedicle biopsy specimens were taken from 68 patients with cervical, thoracic, lumbar, or sacral vertebral lesions, with the patients under local anesthesia. Sixty-one procedures were done with fluoroscopic guidance and seven procedures were done with computed tomography guidance. Twenty-one patients were diagnosed as having infectious spondylodiscitis, three had tuberculosis, two had coccidiomycosis, two had brucellosis, one had blastomycosis, one had an echinococcus cyst, six had primary neoplasms, 14 had metastatic neoplasms, five had osseous repair for insufficiency fractures, seven had osteoporotic fractures, and one had Paget's disease of bone. In the four remaining patients, the biopsy initially was negative but it was proven to be false-negative because of faulty biopsy technique. The percutaneous transpedicle approach for biopsy is safe, efficacious, and cost-effective. False-negative results and complications can be avoided when adhering to the technical details of this procedure.  相似文献   
662.
There is some evidence that taxanes and gemcitabine are effective antitumor agents against small-cell lung cancer (SCLC). A total of 20 chemotherapy-naive patients with extensive disease (ED) SCLC, were treated as a part of the first step of a phase II study, with docetaxel 50 mg/m(2) and gemcitabine 1000 mg/m(2), both administered on day 1 and 8 every 3 weeks up to a total of six cycles. For patients who progressed after the first cycle or had stable disease after the second cycle of chemotherapy, protocol treatment was stopped and further treatment with the standard cisplatin or carboplatin-etoposide combination was administered. Patients were in the vast majority male smokers with a good performance status. A total of 72 cycles was delivered while patients managed to receive the 78 and 84% of the planned dose of docetaxel and gemcitabine, respectively. Only six patients responded partially and the trial ended prematurely since at least seven responses were required among the first 19 patients. With a median follow-up of 13 months, median time to progression (TTP) was 8 months and median survival 9.6 months. Hematological and non-hematological toxicity was generally acceptable while patients tolerated their treatment reasonably well. In conclusion, docetaxel-gemcitabine showed a modest response rate in chemotherapy-naive patients with ED SCLC.  相似文献   
663.
664.
The aim of the study was to investigate the career choices, location preferences and criteria among medical students in Greece. We applied a questionnaire-based analysis using a sample of 591 students of four out of seven Greek Medical Schools. The sample included students of all academic years. The vast majority of students wish to specialize (97.6%), while general practice gathered a very low percentage (1.7%). The scientific challenge (61.4%) and interaction with patients (60.6%) seem to be the major influencing factors for most of the students' specialty preferences, whilst less common variables influencing career choice are the high demand/supply ratio for certain health services (40.4%), the income potential (31.4%), the active tempo (26.2%) and prestige (15%). 70.3% of those asked consider the possibility of specializing abroad. The low concern of Greek medical students for general practice reveals today's drastic deficiency in Greek primary health care. Such a situation will escalate, unless targeted strategies to produce more general practitioners are adopted. Furthermore, the results reflect a lower education and organizing level urging students to specialize abroad. The National Health System (NHS) should be reformed towards a rationalistic distribution of the medical specialties and medical workforce.  相似文献   
665.
The photochemistry and use of recently developed photosensitive precursors to nitric oxide (NO) are reviewed. As "caged NO" donors these precursors are able to deliver NO in a spatially and temporally controllable manner. These properties have made such precursors useful in applications in biology and medicine, especially in elucidating neurophysiological roles of NO and in new cancer therapies.  相似文献   
666.
A review and evaluation of intraurban air pollution exposure models   总被引:1,自引:0,他引:1  
The development of models to assess air pollution exposures within cities for assignment to subjects in health studies has been identified as a priority area for future research. This paper reviews models for assessing intraurban exposure under six classes, including: (i) proximity-based assessments, (ii) statistical interpolation, (iii) land use regression models, (iv) line dispersion models, (v) integrated emission-meteorological models, and (vi) hybrid models combining personal or household exposure monitoring with one of the preceding methods. We enrich this review of the modelling procedures and results with applied examples from Hamilton, Canada. In addition, we qualitatively evaluate the models based on key criteria important to health effects assessment research. Hybrid models appear well suited to overcoming the problem of achieving population representative samples while understanding the role of exposure variation at the individual level. Remote sensing and activity-space analysis will complement refinements in pre-existing methods, and with expected advances, the field of exposure assessment may help to reduce scientific uncertainties that now impede policy intervention aimed at protecting public health.  相似文献   
667.
OBJECTIVE: The aim of this work was to investigate the association between fish consumption and the development of non-fatal acute coronary syndromes (ACS), in a Mediterranean population. METHODS: During 2000-2001, we randomly and stratified selected, from all Greek regions, 848 hospitalised patients (695 males, 58+/-10 years old and 153 females, 65+/-9 years old) who had a first event of ACS and 1078 paired, by region-sex-age, controls without any clinical symptoms or signs of coronary heart disease. RESULTS: On multivariate logistic regression analysis and, after controlling for several potential confounders, we found that fish consumption less than 150 g/week was associated with 38% lower odds of developing ACS as compared to no consumption (odds ratio=0.62, P-value<0.05). In contrast, moderate (150-300 g/week) and high (>300 g/week) fish consumption was not associated with the developing of the disease (odds ratios=1.10 and 1.01, respectively, P-value>0.1). The benefits from low fish consumption were also significant even amongst current smokers and diabetics. CONCLUSION: Moderate fish consumption was independently associated with a significant reduction in the odds of developing ACS. The strength and consistency of this finding has implications for public health and should be explored further.  相似文献   
668.
We recently showed that arsonoliposomes (novel arsenic containg liposomes) demonstrate differential toxicity towards various types of cancer and normal cells, in cell culture studies, as well as anti-parasitic activity. In this study, the in-vivo distribution of the active moiety of these vesicles, As, is evaluated. Sonicated arsonoliposomes were prepared using the arsonolipid with palmitic acid acyl chain (C16) mixed with egg-phosphatidyl choline (PC) and cholesterol (Chol) [C16/PC/Chol at 8:12:10 mol/mol/mol]. A dose of arsonoliposomes, corresponding to 5 mg arsenate/kg was administered by intraperitoneal injection in balb-c mice. At various time points post-injection the mice were sacrificed and the distribution of As in the organs was measured, by atomic absorption spectroscopy. Results demonstrate that a high portion of the dose administered is rapidly excreted; since 1-h post-injection only about 30% of the dose administered was detected cumulatively in the animal tissues. After this the elimination of arsenic was a slow process with a total body elimination rate constant of 0.023 h(-1), corresponding to a half-life of 30 h. Tissues with the highest arsenic concentration during the study period are: spleen-kidneys-stomach, followed by lung, liver, intestines-heart, carcass+skin and finally blood. No acute toxicity, or effect on the body or organ weight of the mice was observed.  相似文献   
669.

Background  

The purpose of this study was to investigate the association between secondhand smoke and the risk of developing a first event of acute coronary syndromes (ACS), i.e. acute myocardial infarction or unstable angina, among non-smokers, in relation to the presence of several other cardiovascular risk factors.  相似文献   
670.
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