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41.
Advances in Health Sciences Education - Spaced education is a learning strategy to improve knowledge acquisition and retention. To date, no robust evidence exists to support the utility of spaced...  相似文献   
42.
BackgroundCultural values are crucial to the practice and impact of patient and public involvement (PPI) in research.ObjectiveTo understand different PPI cultures among research teams and the impacts of PPI associated with each culture type.DesignA participatory action research design.Setting and participantsThe setting was 10 palliative care research projects. Seventeen patients and members of the public and 31 researchers participated.InterventionA programme consisting of four components: (1) training and coaching of patients and the public to prepare them for participation in research, (2) tailored coaching of the 10 research teams over 12‐18 months, (3) a community of practice, and (4) a qualitative evaluation.ResultsWe identified three cultures types: relationship cultures, task cultures, and control cultures. We identified four areas of impact: the project aim became more relevant to the target audience, methodological reliability increased, the research products were better able to reach the public, and the awareness increased, associated with behavioural changes, among researchers regarding PPI.DiscussionA relationship culture appears to be long‐lasting due to impacting the behaviours of the researchers during future projects. Different cultural types require different types of patients and researcher participants, assigned to different tasks.ConclusionsFurther research remains necessary to investigate the support required by researchers to enable relationship‐ and task‐oriented PPI cultures.Patient or public contributionPatient advocates and representatives contributed to our research team throughout the entire research process, as well as within the 10 implementation projects.  相似文献   
43.
European Journal of Epidemiology - The aim of this study was to evaluate the impact of the COVID-19 pandemic lockdown on acute myocardial infarction (AMI) care, and to identify underlying stressors...  相似文献   
44.
It is often assumed that the unattached fraction of the exposure to suspended radon progeny activity can be predicted from particle concentration measurements. While this may be true in many circumstances, there are important exceptions to this rule. In particular, in an atmosphere far from radioactive equilibrium, such as a working area in a mine close to a source of radon and supplied with fresh air, the unattached fraction can be a factor of ten or more greater than indicated by a simple particle concentration measurement. Recent measurements made in a diesel powered uranium mine are presented to illustrate this effect.  相似文献   
45.
Recent experimental studies on the crystallization of calcium salts at different nephron levels support the theory that the initial formation of calcium concrements starts with an intratubular crystallization of calcium phosphate (CaP) and calcium oxalate (CaOx). CaP seems to be the initial crystallization product in pure CaP and mixed calcium phosphate–calcium oxalate (CaPCaOx) concrements, with the formation of CaP crystals at a nephron level above the collecting duct. Urinary macromolecules and cellular degradation products most probably promote this process. During the passage through the collecting duct, CaP might partly or completely dissolve at the lower pH encountered there. This might result in an increased concentration of calcium and hence an increased supersaturation with CaOx, which in turn can bring about a heterogeneous nucleation of CaOx on or around preformed CaP crystals or crystal aggregates. The final result will be mixed CaOxCaP or pure CaOx concrements. Pure CaOx concrements might also be the result of an initial CaOx crystallization at nephron levels above or in the collecting duct under conditions with a high urinary excretion of oxalate. Whether intratubular crystallization of calcium salts results in the formation of small harmless crystals excreted with urine or calcium stones appears to be determined by a complex process, involving kinetic factors that influence crystal growth and crystal aggregation and crystal retention. Received: 24 December 1998 / Accepted: 11 March 1999  相似文献   
46.
To examine the effect of hydroxyapatite (HAP) seed crystals and urinary macromolecules on the crystallization under conditions similar to those in the collecting duct, we evaporated 100 ml samples of salt solutions with an ion composition assumed to correspond to that in the collecting duct without and with HAP seed crystals. The crystallization in seeded solutions was assessed both with and without dialysed urine (dU). After evaporation the number and volume of crystals were recorded in a Coulter Multisizer and the crystal morphology examined with scanning electron microscopy (SEM) and X-ray crystallography. Addition of HAP crystals was apparently followed by an approximately 15–20% increase in heterogeneous nucleation of calcium oxalate (CaOx). In these experiments SEM and X-ray crystallography showed a high percentage of CaOx in the precipitate. In samples reduced to 40–69 ml, addition of dU to the collecting duct solution containing HAP seed resulted in a greater mean (SD) number of crystals; 3895 (1841) in samples with dU and 1785 (583) in samples without. This was mainly explained by an increased mean (SD) number of small crystals. The mean crystal volume was 17.8 (1.1) and 34.3 (9.1) in samples reduced to 40–69 ml with and without dU, respectively. This might reflect the inhibitory effect of dU on the growth and/or aggregation of the CaOx-CaP precipitate or a promoted nucleation resulting in a large number of small crystals. It is concluded that calcium phosphate formed above the collecting duct might induce heterogeneous nucleation of CaOx at lower levels of the renal collecting system, and that urinary macromolecules are powerful modifiers of these processes. Received: 8 July 1998 / Accepted: 12 March 1999  相似文献   
47.
Summary The tensile strength of the muscle fibre surface membrane was estimated (1) from the suction required to burst membrane patches and (2) by aspiration of sarcolemmal vesicles into micropipettes of uniform bore. Each method gave an average value close to 60 N cm–1 for the maximum tension sustainable by normal mouse sarcolemma and only slightly lower values for sarcolemma frommdx mice which lack dystrophin. The elastic modulus of area expansion, as measurable by pipette aspiration of sarcolemmal vesicles, was found to have an average value of 3160 N cm–1 for normal and 2770 N cm–1 formdx mouse sarcolemma.The tensile strength of the sarcolemma is much too small for any differences in it to be the basis for the different osmotic behaviour of normal andmdx muscle fibres reported recently (Menke & Jockusch, 1991). By analogy with the better understood origin of the osmotic fragility of different types of red blood cells, the higher osmotic fragility ofmdx muscle fibres is suggested to be of morphological origin. We postulate that dystrophin functions as an element of the submembrane cytoskeleton so as to maintain the normal folding which safeguards the sarcolemma against mechanical damage.  相似文献   
48.
A 3D-scanner for direct three-dimensional imaging using a --coincidence technique is presented. The characteristics of the system were demonstrated by isoresponse curves and modulation transfer functions. A phantom study showed the possibility of detecting cold nodes when they are invisible in normal scans in large subjects because of masking by overlying activity.  相似文献   
49.
A reduction or reversal of the normal leftward asymmetry of the planum temporale (PT) has been claimed to be typical of dyslexia, although some recent studies have challenged this view. In a population-based study of 20 right-handed dyslexic boys and 20 matched controls, we have measured the PT and the adjacent planum parietale (PP) region in sagittal magnetic resonance images. For the PT, mean left and right areas and asymmetry coefficients were compared. Since a PP area often could not be identified in one or both hemispheres, a qualitative comparison was used for this region. The total planar area (sum of PT and PP) was also compared between the two groups. A dichotic listening (DL) test with consonant–vowel syllables was administered to assess functional asymmetry of language. The results showed a mean leftward PT asymmetry in both the dyslexic and the control group, with no significant difference for the degree of PT asymmetry. Planned comparisons revealed however, a trend towards smaller left PT in the dyslexic group. In control children, but not in the dyslexic children, a significant correlation between PT asymmetry and reading was observed. A mean leftward asymmetry was also found for the total planar area, with no difference between the groups for the degree of asymmetry. Significantly fewer dyslexic children than control children showed a rightward asymmetry for the PP region. Both groups showed a normal right ear advantage on the DL task, with no significant difference for DL asymmetry. No significant correlation was observed between PT asymmetry and DL asymmetry. The present population-based study adds to recent reports of normal PT asymmetry in dyslexia, but indicates that subtle morphological abnormalities in the left planar area may be present in this condition.  相似文献   
50.
Hutter MM  Glasgow RE  Mulvihill SJ 《Surgery》2000,128(2):286-292
BACKGROUND: Some patients have concerns regarding the impact of surgical trainees on the quality of care that they receive in teaching hospitals. No population-based data exist that describe outcomes of surgical procedures in teaching and nonteaching hospitals; however, institutional data suggest that teaching hospitals provide high-quality care. We hypothesized that the presence of a general surgery residency program (GSRP) is associated with superior outcomes for pancreatic resection, a complex surgical procedure. METHODS: A retrospective, population-based, risk-adjusted analysis of 5696 patients who underwent major pancreatic resection compares the outcomes of patients treated at hospitals with a GSRP (GSRP+) and those hospitals without a GSRP (GSRP-). RESULTS: GSRP+ hospitals had a lower operative mortality rate (8.3% vs 11.0%; P <. 001), a lower percentage of patients discharged to another acute care hospital or skilled nursing facility (6.5% vs 13.0%; P <.001), and a longer length of stay compared with GSRP- hospitals (22.1 +/- 0.4 days vs 19.6 +/- 0.3 days; P <.001). The observed difference in hospital mortality rates was not significant after an adjustment was made for patient mix and hospital volume (9.7% vs 10.0%). However, superior outcomes were found in the university teaching hospitals, as compared with the affiliated teaching and the nonteaching hospitals (5.3% [P <.001] vs 11.4% vs 11.0%; risk adjusted, 8.0% [P <.05] vs 10.9% vs 10.0%). CONCLUSIONS: The presence of surgical trainees does not have an adverse impact on the quality of care for One complex procedure, pancreatectomy, and is associated with superior operative mortality rate in university teaching hospitals.  相似文献   
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