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941.
942.
IntroductionClinical reasoning encompasses the process of data collection, synthesis, and interpretation to generate a working diagnosis and make management decisions. Situated cognition theory suggests that knowledge is relative to contextual factors, and clinical reasoning in urgent situations is framed by pressure of consequential, time-sensitive decision-making for diagnosis and management. These unique aspects of urgent clinical care may limit the effectiveness of traditional tools to assess, teach, and remediate clinical reasoning.MethodsUsing two validated frameworks, a multidisciplinary group of clinicians trained to remediate clinical reasoning and with experience in urgent clinical care encounters designed the novel Rapid Evaluation Assessment of Clinical Reasoning Tool (REACT). REACT is a behaviorally anchored assessment tool scoring five domains used to provide formative feedback to learners evaluating patients during urgent clinical situations. A pilot study was performed to assess fourth-year medical students during simulated urgent clinical scenarios. Learners were scored using REACT by a separate, multidisciplinary group of clinician educators with no additional training in the clinical reasoning process. REACT scores were analyzed for internal consistency across raters and observations.ResultsOverall internal consistency for the 41 patient simulations as measured by Cronbach’s alpha was 0.86. A weighted kappa statistic was used to assess the overall score inter-rater reliability. Moderate reliability was observed at 0.56.DiscussionTo our knowledge, REACT is the first tool designed specifically for formative assessment of a learner’s clinical reasoning performance during simulated urgent clinical situations. With evidence of reliability and content validity, this tool guides feedback to learners during high-risk urgent clinical scenarios, with the goal of reducing diagnostic and management errors to limit patient harm.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-022-07513-5.  相似文献   
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Background: HIV infection results in immunometabolic reprogramming. While we are beginning to understand how this metabolic reprogramming regulates the immune response to HIV infection, we do not currently understand the impact of ART on immunometabolism in people with HIV (PWH). Methods: Serum obtained from HIV-infected (n = 278) and geographically matched HIV seronegative control subjects (n = 300) from Rakai Uganda were used in this study. Serum was obtained before and ~2 years following the initiation of ART from HIV-infected individuals. We conducted metabolomics profiling of the serum and focused our analysis on metabolic substrates and pathways assocaited with immunometabolism. Results: HIV infection was associated with metabolic adaptations that implicated hyperactive glycolysis, enhanced formation of lactate, increased activity of the pentose phosphate pathway (PPP), decreased β-oxidation of long-chain fatty acids, increased utilization of medium-chain fatty acids, and enhanced amino acid catabolism. Following ART, serum levels of ketone bodies, carnitine, and amino acid metabolism were normalized, however glycolysis, PPP, lactate production, and β-oxidation of long-chain fatty acids remained abnormal. Conclusion: Our findings suggest that HIV infection is associated with an increased immunometabolic demand that is satisfied through the utilization of alternative energetic substrates, including fatty acids and amino acids. ART alone was insufficient to completely restore this metabolic reprogramming to HIV infection, suggesting that a sustained impairment of immunometabolism may contribute to chronic immune activation and comorbid conditions in virally suppressed PWH.  相似文献   
947.
We outline procedures to calculate small-angle scattering (SAS) intensity functions from 2-dimensional electron-microscopy (EM) images. Two types of scattering systems were considered: (a) the sample is a set of particles confined to a plane; or (b) the sample is modelled as parallel, infinitely long cylinders that extend into the image plane. In each case, an EM image is segmented into particle instances and the background, whereby coordinates and morphological parameters are computed and used to calculate the constituents of the SAS-intensity function. We compare our results with experimental SAS data, discuss limitations, both general and case specific, and outline some applications of this method which could potentially complement experimental SAS.

We outline procedures to calculate small-angle scattering (SAS) intensity functions from 2-dimensional electron-microscopy (EM) images for two types of scattering systems.

The structures of nanoparticulate systems are commonly characterized by various forms of electron microscopy (EM) and small-angle scattering (SAS) methods. The size and shape of nanoparticles, as well as their spatial-distribution functions, are of particular interest since they govern their structure–function relationships and thus their nanotechnological prospects.1–6 EM and SAS data are highly complementary. For example, the former images a specific section of a nanomaterial, while the latter realizes its bulk structure by averaging signals obtained from a larger overall area and depth reflective of the sample thickness and beam size. There exists a high degree of overlap in the length scale that is interrogated by EM and SAS data on the same nanomaterial. Yet, these data are necessarily acquired separately and they are analyzed independently. Nevertheless, if suitably processed, the data from one metrology could be used to reconstruct the other. This could draw out the maximum possible structural information about a nanomaterial, or allow data from both sources to be fused to obtain more accurate insights or even highlight processes that result in discrepancies between data from the two methods.This work presents two case studies in which we calculate SAS data from 2-D EM images where (1) the particles being characterized exist on a plane; (2) the sample being imaged can be modelled as parallel, infinitely long cylinders that extend into the image plane. In both cases, we discuss limitations that result in discrepancies between image-obtained SAS intensities and those obtained experimentally. Despite these limitations, we discuss how this method can be complementary to small-angle scattering measurements, by informing experimental design decisions and aiding in model selection. The second case that we present was partially explored by Worthington and Inouye,7 and later Meek and Quantock8 as well as Quantock et al.9 They studied the interfibril distance of collagen fibres in animal corneas by calculating an interference function from pairwise distances of points obtained from an EM image. Their interference function is related to the structure factor which we include in our calculation of SAS intensities, along with form factors which we additionally compute from images. Grubb et al.10 studied the effect of the orientation of lamellar stack structures on SAXS patterns. The authors did this by generating synthetic images of arrays of lamellar stacks and simulating SAXS data using the 2-D Fourier transform, where they use the Fourier Slice theorem to obtain a 2-D slice of the 3-D transform.11 Afsari et al.12 and Kim et al.13 outline a procedure for calculating small-angle X-ray scattering (SAXS) data from cryo-EM images. Their work makes use of the fact that averaging the correlation functions of many cryo-EM images is equivalent to the Abel transform of SAXS data. Their work is complementary to ours as both methods can be applied under different circumstances. Our work is relevant in situations where image-processing and computer-vision techniques can be employed to segment single EM images and determine morphological and structural information about the scatterers; theirs is relevant when one has numerous cryo-EM images of the same sample.  相似文献   
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This study compares different immunosuppressive regimens in the treatment of the lupus-like nephritis of NZB/W mice. Groups of 5-month-old female NZB/W mice were given azathioprine, cyclophosphamide and methylprednisolone in all one-, two- and three-drug regimens, each drug in the relatively low dose of 1.5 mg/kg/day. Treatment for 3 months with one or two drugs resulted in modest suppression of NZB/W disease. Mice receiving all three drugs had significantly less proteinuria, lower titers of anti-DNA antibody and less severe, histologically evident renal involvement than mice treated with one or two drugs. Survival at 1 year was 10% for untreated controls, 44% for one-drug-treated, 37% for two-drug-treated and 86% for the three-drug-treated mice. The survival for the three-drug regimen was significantly longer than any other group (P < 0.01). The three-drug regimen was synergistic, since mice treated with each drug at three times the dose had significantly more proteinuria after 3 months of treatment and lowered 1 year survival (33%). The beneficial effects of triple-drug therapy were attained without increased toxicity. This study represents the first controlled evaluation of single versus combination therapy in a model of autoimmune disease. Based on these results, a controlled evaluation of triple-drug therapy in human systemic lupus erythematosus appears warranted.  相似文献   
950.
Many azoospermic men do not possess mature spermatozoa at the time of surgical sperm extraction.This study is a systematic review and meta-analysis evaluating o...  相似文献   
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