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991.
Outer-membrane vesicles (OMVs) have inherent adjuvant properties, and many vaccines use OMV as vaccine components. Utilizing the adjuvant properties of OMV could lead to the formulation of vaccines that are less expensive and potentially more immunogenic than covalently conjugated polysaccharide vaccines. We evaluated the adjuvant effect in Balb/c mice of combinations of OMV from Neisseria meningitidis serogroup A and W135 as compared to that of the non-covalently conjugated capsular polysaccharide A. Both antigens were adsorbed onto aluminum hydroxide. The mice were given a booster dose of plain polysaccharide A to stimulate an immunologic memory response. Subclasses determination and cytokine assays demonstrated the capacity of OMV to induce a IgG2a/IgG2b isotype profile and IFN-γ production, suggesting the induction of a Th1 pattern immune response. Lymphoproliferative responses to OMVs were high, with affinity maturation of antibodies observed. Bactericidal titers after the booster dose were also observed. Memory B cells and long-term memory T cells were also detected. The results of this study indicate that combined meningococcal serogroup A and W135 OMV can activate cell-mediated immunity and induce a long-term memory response.  相似文献   
992.
A new series of oligomethylene bis(nitrophenylureylbenzamide) receptors were synthesized varying the relative position of the urea and amide groups (ortho4 and meta8) and the length of the oligomethylene chain (C2 to C8). An anion recognition study was performed with TBAX salts (X = AcO, BzO, F, H2PO4, and HP2O73−) by UV-vis and 1H NMR. The flexibility of these receptors allows a cooperative effect of both ureylbenzamide units in the receptors. Noteworthy, the ortho position favored the 1 : 1 stoichiometry in the complexes with the carboxylates. The formation of 2 : 1 receptor–anion complexes with both types of receptors 4 and 8 and with hydrogen pyrophosphate and high log K values obtained were very significant in this work. The NMR studies evidenced the formation of supramolecular complexes, even in a competitive solvent, such as DMSO.

Synthesis and supramolecular interaction of new oligomethylene bis(4-nitrophenylureylbenzamide) receptors with different anions.  相似文献   
993.
A new nematode species, Foleyellides rhinellae sp. nov. (Onchocercidae), is described from specimens found in the body cavity of the cane toad, Rhinella marina (Linnaeus) (Anura, Bufonidae), in the Laguna de Coyuca, Guerrero, in the Pacific slope of Mexico. The new species differs from the other nine species of Foleyellides by infecting bufonid anurans and by the number and arrangement of caudal papillae. Other distinguishing feature of the new species is the size of the left spicule (0.16–0.23 long), the smallest recorded among the species included in the genus. Foleyellides rhinellae sp. nov. is the second known species of the genus recorded from amphibians of Mexico.  相似文献   
994.

Purpose

To analyse the muscle adaptations induced by two protocols of isometric training performed at different muscle lengths.

Methods

Twenty-eight subjects were divided into three groups: one (K90) performed isometric training of the knee extensors at long muscle lengths (90° of knee flexion) for 8 weeks, and the second group (K50) at short muscle lengths (50°). The subjects of the third group acted as controls. Isokinetic dynamometry was utilized to analyse the net moment–angle relationship and vastus lateralis muscle thickness at three different locations, and pennation angles and fascicle length at 50 % of thigh length were measured at rest with ultrasonography.

Results

Only subjects from K90 group showed significant increases in isokinetic strength (23.5 %, P < 0.001), while K50 group showed no increases in isokinetic strength: (10 %, P > 0.05). There was a shift in the angle of peak torque of the K90 group to longer muscle lengths (+14.6 %, P = 0.002) with greater increases in isokinetic strength, while the K50 angle shifted to shorter muscle lengths (?7.3 %, P = 0.039). Both training groups showed significant increases in muscle thickness, (K90 9–14 % vs. K50 5–9 %) but only K90 significantly increased their pennation angles (11.7 %, P = 0.038). Fascicle lengths remained unchanged.

Conclusions

Isometric training at specific knee angles led to significant shifts of peak torque in the direction of the training muscle lengths. The greater strength gains and the architectural changes with training at long muscle lengths probably come from a combination of different factors, such as the different mechanical stresses placed upon the muscle–tendon complex.  相似文献   
995.
ObjectiveThe question of whether breastfeeding has a protective effect against the development of overweight or obesity later in life remains controversial, especially during adolescence. The objective was to assess the relationship between breastfeeding and adolescents’ body composition.MethodsThe HELENA study is a cross-sectional study involving 3,528 adolescents from 10 European cities. The outcome measures were body weight and height, subscapular skinfolds as well as waist circumferences. Breastfeeding, smoking status, and parental socioeconomic status were assessed by self-administered questionnaires. Dietary intake was recorded using two 24-hour recall surveys. Two adjustment approaches were used: i) covariance analysis adjusted for confounding factors (propensity score adjustment) and ii) multivariate quantile regression.ResultsAfter adjustment, no significant associations were observed between breastfeeding and body composition parameters (BMI Z-score; sum of skinfolds; waist-to-height ratio). An adjusted quantile regression analysis showed a non-significant trend for a protective effect of breastfeeding toward the highest percentiles of adiposity in boys but not in girls. This is of particular interest with respect to the superiority of the waist-to-height ratio over waist circumference and BMI for detecting cardiometabolic risk factors.ConclusionThis first European study, including a large set of factors influencing adolescents’ body composition, showed a non-significant trend toward a protective effect of breastfeeding on highest percentiles of adolescent''s abdominal adiposity.Key Words: Breastfeeding, Body composition, Adolescents, Waist-to-height ratio, BMI, Propensity score  相似文献   
996.
BRIEF REPORT The activity of natural killer (NK) cells is partially regulated by killer cell immunoglobulin-like receptors (KIRs) interacting with human leukocyte antigen C (HLA-C) ligands.1 The ligands of several inhibitory (2DL and 3DL) and activating (2DS and 3DS) KIR have been described.  相似文献   
997.
998.
999.
The global health scenario shows an epidemic of non‐communicable diseases that lead to long‐term chronic conditions, some of which are incurable. Many infectious diseases, owing to their development and length, also generate chronic conditions. Similarly, non‐morbid states, such as pregnancy, and some life cycles such as adolescence and ageing, follow the same logic. Among all these chronic conditions there is a significant interrelationship with oral health, both in parallel events and common risk factors. This article presents cross‐sectional qualitative research into World Health Organisation recommended health policies to address chronic conditions. Several documents published by the organisation were analysed to verify the presence of references to oral health in relation to chronic conditions, particularly cardiovascular diseases and diabetes as these most frequently have oral manifestations. The analysis showed no significant references to oral health or its indicators within the published texts. The study recognises the value of the work developed by the World Health Organisation, as well as its worldwide leadership role in the development of health policies for chronic conditions. This article proposes a coalition of dentistry organisations that could, in a more forceful and collective way, advocate for a greater presence of oral health in drafting policies addressing chronic conditions.  相似文献   
1000.

Introduction

The morphology of the supernumerary third root (radix) in mandibular first molars was examined by micro–computed tomography (μCT) scanning.

Methods

Nineteen permanent mandibular first molars with radix were scanned in a μCT device to evaluate their morphology with respect to root length, root curvature direction, location of radix, apical foramen, accessory canals and apical deltas, and distance between canal orifices as well as 2- and 3-dimensional parameters of the canals (number, area, roundness, major/minor diameter, volume, surface area, and structure model index). Quantitative data were analyzed by 1-way analysis of variance and the Tukey test (α = 0.05).

Results

The mean length of the mesial, distal, and radix roots was 20.36 ± 1.73 mm, 20.0 ± 1.83 mm, and 18.09 ± 1.68 mm, respectively. The radix was located distolingually (n = 16), mesiolingually (n = 1), and distobuccally (n = 2). In a proximal view, most radix roots had a severe curvature with buccal orientation and a buccally displaced apical foramen. The spatial configuration of the canal orifices on the pulp chamber floor was mostly in a trapezoidal shape. The radix root canal orifice was usually covered by a dentinal projection. The radix differed significantly from the mesial and distal roots for all evaluated 3-dimensional parameters (P < .05). The radix canal had a more circular shape in the apical third, and the mean size of the minor diameter 1 mm short of the foramen was 0.25 ± 0.10 mm.

Conclusions

The radix root is an important and challenging anatomic variation of mandibular first molars, which usually has a severe curvature with a predominantly distolingual location, and a narrow root canal with difficult access.  相似文献   
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