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931.
Zusammenfassung An einigen Beispielen wird gezeigt, daß die mechanische Beeinflussung des Knochengewebes nicht so sehr von der Richtung äußerer einwirkender Kräfte abhängig ist als vielmehr von den aus diesen Kräften entstehenden Druckspannungen und deren Orientierung zu den vorhandenen, ausgebildeten Druckspannungsrichtungen (Trajektorien) des jeweiligen Knochens. Auswertungen, die sich nur auf Druck- und Zugwirkungen äußerer Kräfte beschränken, können nur unbefriedigende Antworten geben.
Summary The effect of mechanical forces on bone depends not so much on the direction of the externally acting forces but more on the compressive strain originating on those forces and their orientation with respect to the existing trajectories of the respective bones. This fact is demonstrated by some examples. Analyses, based solely on pressure and tension effects of externally acting forces do not give satisfactory explanations.

Résumé A l'aide de quelques examples, on démontre que l'influence mécanique sur le tissue osseux ne dépend pas tant de la direction des forces externes, mais plutôt des tensions compressives, produites par ces forces, et de leur orientation vers les directions formées par les tensions compressives (trajectoires) de l'os en question. Les appréciations, restreintes seulement aux effects de compression et de traction des forces externes, ne sont pas capables de donner des réponses satisfaisantes.
  相似文献   
932.
Eight healthy young men participated in a 90-d metabolic balance study designed to assess the adequacy of 1 g of protein (N X 6.25) per kilogram body weight per day provided by a predominantly vegetable diet. The mean gross energy intake of the subjects was 49 kcal/(kg X d). The individuals received the experimental diet for eleven 8-d experimental periods. Three isoenergetic, isonitrogenous meals were served at 0800, 1200 and 1900. Anthropometric measurements and biochemical determinations in blood were made at the beginning of the study and afterwards at regular 15-d intervals. Body weight was measured daily. The mean overall weight change for the group was -0.8 kg. The mean daily urinary nitrogen output decreased from an initial value of 134.6 mg/(kg X d) to a final figure of 115.1 mg/(kg X d) (P less than 0.01), while the daily fecal N decreased from 31.5 to 26.3 mg/(kg X d) (P less than 0.05). Mean cumulative nitrogen balances were slightly positive for seven out of the eight individuals with an overall mean nitrogen balance value of +6.7 mg N/(kg X d). Biochemical and hematological values showed no significant changes throughout the study, except for a decrease in serum cholesterol. It is concluded that the "Chilean" mixed diet fed at the level of 1 g of protein per kilogram body weight per day with sufficient energy meets the long-term protein-energy needs of healthy young men, thus supporting the 1984 FAO/WHO/UNU safe recommended daily protein allowance of 0.75 g of reference protein, with a correction for the lower digestibility of vegetable sources.  相似文献   
933.
Diclofensine increases the availability of the three neurotransmitters dopamine, noradrenaline and serotonin by inhibiting their re-uptake into synaptosomes. In a randomized double-blind parallel-group comparative study, a total of 40 patients, some hospitalized (n = 11) and some ambulatory (n = 29), mean age of 39.6 years +/- 12 S.D., with psychoreactive depression were treated for 30 days with 2 X 25 mg/day of diclofensine or with placebo. The assessments of efficacy indicated superiority of diclofensine over placebo. The number of "improved" patients (reduction in the overall depression scores by 50% or better) relative to that of "not improved" patients, was found to be statistically significant (p less than 0.025) on day 10 of treatment. With respect to individual symptoms, anxiety showed a significantly (p less than 0.05) better improvement under diclofensine than under placebo. Side effects were observed in one patient in each group. One patient (diclofensine group) reported a transient slight somnolence, the other (placebo group) reported episodes of transient dizziness. Based on these data it can be concluded that diclofensine is a well tolerated and effective drug for the treatment of symptoms associated with reactive depressions.  相似文献   
934.
Quality of Life Research - The relation between diet and maternal mental health during pregnancy might be relevant to prevent adverse materno-foetal outcomes. This study examined the association of...  相似文献   
935.
Quality of Life Research - The aim of this systematic review was to examine the association between physical activity (PA) and Health-Related Quality of Life (HRQoL) as well as other...  相似文献   
936.
Quality of Life Research - This study aimed to determine predictors of health-related quality of life (HRQoL) in Parkinson's disease (PD) and to explore their predictive value before and after...  相似文献   
937.
Maternal and Child Health Journal - The aim of this study was to estimate the association between individual and contextual characteristics related to maternal work and exclusive breastfeeding...  相似文献   
938.
Maternal and Child Health Journal - Dietary patterns can influence maternal and child health outcomes. The study aims to characterize dietary patterns during pregnancy as well as to identify their...  相似文献   
939.
BackgroundObesity has been described as a protective factor in cardiovascular and other diseases being expressed as ‘obesity paradox’. However, the impact of obesity on clinical outcomes including mortality in COVID-19 has been poorly systematically investigated until now. We aimed to compare clinical outcomes among COVID-19 patients divided into three groups according to the body mass index (BMI).MethodsWe retrospectively collected data up to May 31st, 2020. 3635 patients were divided into three groups of BMI (<25 kg/m2; n = 1110, 25?30 kg/m2; n = 1464, and >30 kg/m2; n = 1061). Demographic, in-hospital complications, and predictors for mortality, respiratory insufficiency, and sepsis were analyzed.ResultsThe rate of respiratory insufficiency was more recorded in BMI 25?30 kg/m2 as compared to BMI < 25 kg/m2 (22.8% vs. 41.8%; p < 0.001), and in BMI > 30 kg/m2 than BMI < 25 kg/m2, respectively (22.8% vs. 35.4%; p < 0.001). Sepsis was more observed in BMI 25?30 kg/m2 and BMI > 30 kg/m2 as compared to BMI < 25 kg/m2, respectively (25.1% vs. 42.5%; p = 0.02) and (25.1% vs. 32.5%; p = 0.006). The mortality rate was higher in BMI 25?30 kg/m2 and BMI > 30 kg/m2 as compared to BMI < 25 kg/m2, respectively (27.2% vs. 39.2%; p = 0.31) (27.2% vs. 33.5%; p = 0.004). In the Cox multivariate analysis for mortality, BMI < 25 kg/m2 and BMI > 30 kg/m2 did not impact the mortality rate (HR 1.15, 95% CI: 0.889?1.508; p = 0.27) (HR 1.15, 95% CI: 0.893?1.479; p = 0.27). In multivariate logistic regression analyses for respiratory insufficiency and sepsis, BMI < 25 kg/m2 is determined as an independent predictor for reduction of respiratory insufficiency (OR 0.73, 95% CI: 0.538?1.004; p = 0.05).ConclusionsHOPE COVID-19-Registry revealed no evidence of obesity paradox in patients with COVID-19. However, Obesity was associated with a higher rate of respiratory insufficiency and sepsis but was not determined as an independent predictor for a high mortality.  相似文献   
940.
ObjectiveTo determine if visceral adipose tissue (VAT) area measured through MRI can be used opportunistically to assess the presence of cardiometabolic risk factors and compare its performance to simpler adiposity measures.MethodsA cross-sectional analysis was carried out on a subset of 1683 participants (856 women) from the Adiposity Phenotype Study (mean age = 69.2y; range 59.9–77.4). The association of total VAT area (sum of four cross sections, L1–L2, L2–L3, L3–L4, L4–L5) and each location, as well as BMI and body fat % (per SD) with the metabolic syndrome (MetSx) or its components was evaluated through logistic regression analysis.ResultsTotal VAT can be accurately predicted using all sites evaluated (R2 range = 0.82?0.96). In men, VAT did not show a superior association to MetSx compared to BMI in men. However, in women, VAT was consistently superior to BMI and body fat % in its association to MetSx, independent of ethnicity [odds ratio for BMI, body fat %and total VAT area = 2.25 (95% CI: 1.93–2.62); 1.66 (95% CI: 1.36–2.03); 6.20 (95% CI: 4.69–8.21) respectively in all women]. Ethnic-specific odds ratios to MetSx in women ranged from 5.38 to 8.63 for total VAT area and 2.12–4.08 for BMI.ConclusionTotal VAT area can be accurately predicted from individual VAT regions in men and women and offers superior association to BMI for MetSx in women but not in men for five ethnicities. Therefore, opportunistic screening for elevated VAT area in women may be warranted across multiple ethnic groups.  相似文献   
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