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81.
We prospectively evaluated performance of 63 referrals to a memory disorders clinic who received the Medical Symptom Validity Test (MSVT) as part of their standard neuropsychological evaluation. The patients were grouped based on independent medical diagnoses and presence or absence of a potential financial incentive to under-perform. Twenty-seven patients (42.9%) scored below cutoffs on the MSVT symptom validity indices. Two individuals in the potential financial incentive group showed clear signs of invalid responding (18.2%). Twenty-two of the remaining 25 patients who failed the symptom validity indices corresponded to the dementia profile. Three individuals did not correspond to the dementia profile but are thought to have performed validly representing a 4.8% false positive rate. When considering all MSVT indices, the base rate of invalid responding in the potential financial incentive to under-perform group increased to 27.3%. Combining all groups our base rate of invalid responding was 4.8%. Specific performances are presented.  相似文献   
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This editorial introduces the special series in the International Journal of Behavioral Nutrition and Physical Activity on the Pro Children study (Promoting and Sustaining Health through Increased vegetable and Fruit Consumption among European Schoolchildren). The Pro Children study is a new and innovative study that takes a cross -national approach to identifying the factors associated with fruit and vegetables consumption in European children (from nine countries) and evaluating a multi-centre intervention programme. A full set of papers on many aspects of the study will appear as a series in the IJBPNA allowing a more detailed view of design, behavioural theoretical constructs, action, methods for implementation, assessment tools, impacts and outcomes to be reported. Areas for future work will also be identified and discussed in the context of the 21st century developed world environment which is superb at encouraging the promotion of energy dense foods and drinks.  相似文献   
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OBJECTIVES: Assessment of morphological characteristics of lymphnodes studied ex-corpore by echoendoscopy--shape, sharpness of limits, echogenicity and dimensions--to categorize them either as metastatic or non-metastatic. MATERIAL AND METHODS: Fifty-four lymphnodes were studied. They were identified and studied by echoendoscopy in fresh surgical specimens of oesophagus, stomach and rectum. Eight nodal characteristics were evaluated. The data obtained were studied by multivariate analysis using the logistical estimate method in two different statistical models. RESULTS: In model 1, logistical estimate demonstrated that well-defined limits (WDL) of the lymphnodes and the association of hypoechogenicity and round shape were the most significant variables suggesting the presence of invasion. In model 2, the most significant variables were WDL, round shape and association of round shape with WDL. The first model had a high sensitivity of 93.1% and specificity of 68% whereas the second model had a greater specificity of 84%, with a slight fall in sensitivity. CONCLUSION: These models might have an application to clinical practice particularly in the pre-operative assessment of patients with oesophageal carcinoma, gastric carcinoma or rectal carcinoma.  相似文献   
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The cellular complexity of the brain (some estimate that there are up to 103 different cell types) is exceeded by the synaptic complexity, with each of the ∼1011 neurons in the brain having around 103–104 synapses. Proteomic studies of the synapse have revealed that the postsynaptic density is the most complex multiprotein structure yet identified, with ∼103 different proteins. Such studies, however, use brain tissue with many different regions and therefore different cell types, and there is clear potential for heterogeneity of protein content at different synapses within and between brain regions. Although large-scale mRNA-based assays are in progress to map this sort of complexity at the cellular level, and indeed all brain-expressed genes, analysis of protein distribution (at synapses and other structures) is still in the very early stages. We review existing large-scale protein expression studies and the specific technical obstacles that need to be overcome before applying the scaling used in nucleic acid based approaches.  相似文献   
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BACKGROUND: Portugal has one of the highest mortality rates from stroke, a high prevalence of hypertension and probably a high salt intake level. AIM: To evaluate Portuguese salt intake levels and their relationship to blood pressure and arterial stiffness in a sample of four different adult populations living in northern Portugal. METHODS: A cross-sectional study evaluating 24-hour urinary excretion of sodium (24 h UNa+), potassium and creatinine, blood pressure (BP), and pulse wave velocity (PWV) as an index of aortic stiffness in adult populations of sustained hypertensives (HT), relatives of patients with previous stroke (Fam), university students (US) and factory workers (FW), in the context of their usual dietary habits. RESULTS: We evaluated a total of 426 subjects, mean age 50 +/- 22 years, 56% female, BMI 27.9+/-5.1, BP 159/92 mmHg, PWV 10.4+/-2.2 m/s, who showed mean 24h UNa+ of 202 +/- 64 mmol/d, corresponding to a daily salt intake of 12.3 g (ranging from 5.2 to 24.8). The four groups were: HT: n = 245, 49 +/- 18 years, 92% of those selected, 69% treated, BP 163/94 mmHg, PWV 11.9 m/s, 24 h UNa+ 212 mmol/d, i.e. 12.4 g/d of salt); Fam: n = 38, 64 +/- 20 years, 57 % of those selected, BP 144/88 mmHg, PWV 10.5 m/s, 24 h UNa+ 194 mmol/d, i.e. 11.1 g/d of salt; US: n = 82, 22 +/- 3 years, 57% of those selected, BP 124/77 mmHg, PWV 8.7 m/s, 24h UNa+ 199 mmol/d, i.e. 11.3 g/d of salt; FW: n = 61, 39 9 years, 47% of those selected, BP 129/79 mmHg, PWV 9.5 m/s, 24 h UNa+ 221 mmol/d, i.e. 12.9 g/d of salt. The ratio of urinary sodium/potassium excretion (1.9 (0.4) was significantly higher in HT than the other three groups. In the 426 subjects, 24h UNa+ correlated significantly (p < 0.01) with systolic BP (r = 0.209) and with PWV (r=0.256) after adjustment for age and BP. Multivariate analysis showed that BP, age and 24h UNa+ correlated independently with PWV taken as a dependent variable. CONCLUSIONS: Four different Portuguese populations showed similarly high mean daily salt intake levels, almost double those recommended by the WHO. Overall, high urinary sodium excretion correlated consistently with high BP levels and appeared to be an independent determining factor of arterial stiffness. These findings suggest that Portugal in general has a high salt intake diet, and urgent measures are required to restrict salt consumption in order to prevent and treat hypertensive disease and to reduce overall cardiovascular risk and events.  相似文献   
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The role of interleukin 6 (IL-6) in the growth of five multiple myeloma-derived cell lines was characterized. The U266 and RPMI 8226 cell lines demonstrated increased DNA synthesis when cultured with exogenous IL-6, expressed IL-6 cell surface receptors (IL-6Rs) and expressed mRNA for IL-6R. However, these cells did not secrete detectable IL-6 protein, and a neutralizing antibody to IL-6 did not inhibit their growth. Three other myeloma-derived cell lines ARH-77, IM-9 and HS-Sultan did not respond to exogenous IL-6, secrete IL-6 or express cell surface IL-6Rs. The IL-6 responsive cell lines bore late B-cell surface antigens (Ags), CD38 and PCA-1, whereas those lines which were non-IL-6 responsive strongly expressed B1 (CD20) and B4 (CD19) Ags, representing earlier stages in B-cell differentiation. Finally, the two IL-6 responsive cell lines did not express Epstein-Barr virus (EBV) proteins; in contrast, EBV encoded proteins typically expressed during latency could be detected in the three non-IL-6 responsive lines, confirming infection with virus. These studies clarify the heterogeneity observed in the myeloma cell line phenotype and biology and suggest that the U266 and RPMI 8226 cell lines, which express IL-6 cell surface receptors and are IL-6 responsive, may be useful for further study of IL-6 signal transduction in and related IL-6 mediated growth of myeloma in vivo. In contrast, those cell lines which are IL-6-independent provide a model for further study of EBV transformation and IL-6-dependent growth mechanisms in malignancy.  相似文献   
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