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21.
Small single-institutional studies performed prior to the introduction of organ allocation using the Model for End-Stage Liver Disease (MELD) suggest that early airway extubation of liver transplant recipients is a safe practice. We designed a multicenter study to examine adverse events associated with early extubation in patients selected for liver transplantation using MELD score. A total of 7 institutions extubated all patients meeting study criteria and reported adverse events that occurred within 72 hours following surgery. Adverse events were uncommon: occurring in only 7.7% of 391 patients studied. Most adverse events were pulmonary or surgically related. Pulmonary complications were usually minor, requiring only an increase in ambient oxygen concentration. The majority of surgical adverse events required additional surgery. Analysis of a limited set of perioperative variables suggest that blood transfusions and technical factors were associated with an increased risk of adverse events. In conclusion, while early extubation appears to be safe under specified circumstances, there are performance differences between institutions that remain to be explained.  相似文献   
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Physical inactivity is associated with alteration of normal physiologic processes leading to muscle atrophy, reduced exercise capacity, insulin resistance, and altered energy balance. Bed rest studies in human beings using stable isotopes of amino acids indicate that muscle unloading decreases the turnover rates of muscle and whole-body proteins, with a prevailing inhibition of protein synthesis. In the fasting state, muscle and whole-body nitrogen loss was not accelerated during bed rest. In experimental postprandial states, the amino acid-mediated stimulation of protein synthesis was impaired, whereas the ability of combined insulin and glucose infusion to decrease whole-body proteolysis was not affected by muscle inactivity. Thus, an impaired ability of protein/amino acid feeding to stimulate body protein synthesis is the major catabolic mechanism for the effect of bed rest on protein metabolism. This suggests that a protein intake level greater than normal could be required to achieve the same postprandial anabolic effect during muscle inactivity. Metabolic adaptation to muscle inactivity also involves development of resistance to the glucoregulatory action of insulin, decreased energy requirements, and increased insulin and leptin secretion. These alterations may lead to the development of the metabolic syndrome that is defined as the association of hyperinsulinemia, dyslipidemia, hypertension, hyperglycemia, and abdominal obesity. This cluster of metabolic abnormalities is a risk factor for coronary artery disease and stroke. Evidence indicates that exercise training programs may counteract all of these abnormalities both in healthy sedentary subjects and in patients affected by a variety of chronic disease states.  相似文献   
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Technetium-99m methoxyisobutylisonitrile (MIBI), like thallium-201, has recently been introduced as a myocardial perfusion agent and is now also showing very promising results in parathyroid scintigrapy. The results of 201Tl/99mTc-pertechnetate and 99mTc-MIBI/99mTc-pertechnetate subtraction scintigraphy, ultrasonography and computed tomography are presented in a series of 43 patients operated on for hyperparathyroidism. All four imaging modalities were confirmed to be reliable, scintigraphy being the most accurate. Sensitivities ranged from 81% to 95%, that of 99mTc-MIBI being the highest. Moreover this tracer, which has more favourable physical and also biochemical properties, yielded images of superior quality. This allowed localization of the lesion by visual inspection only in as many as 86% of the patients with positive 99mTc-MIBI/99mTc-pertechnetate subtraction scintigraphy. We believe that the higher sensitivity, superior image quality and lower cost of 99mTc-MIBI imaging will make 99mTc-MIBI the new radiopharmaceutical of choice for parathyroid scintigraphy (when one takes into account the stability of labelling with large activities it is possible to perform three or four cardiac studies together with one parathyroid scintigraphic examination using one lyophililzed vial).  相似文献   
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The Authors describe a rare case of cholestatic jaundice which persisted due to compression of the biliary tract by a hugely swollen gallbladder due to cystic duct syndrome.  相似文献   
25.
Mutations in the dysferlin gene (DYSF) on chromosome 2p13 cause distinct phenotypes of muscular dystrophy: limb-girdle muscular dystrophy type 2B (LGMD2B), Miyoshi myopathy (MM), and distal anterior compartment myopathy, which are known by the term 'dysferlinopathy'. We performed mutation analyses of DYSF in 14 Italian patients from 10 unrelated families with a deficiency of dysferlin protein below 20% of the value in normal controls by immunoblotting analysis. We identified 11 different mutations, including eight missense and three deletion mutations. Nine of them were novel mutations. We also identified a unique 6-bp insertion polymorphism within the coding region of DYSF in 15% of Italian population, which was not observed in East Asian populations. The correlation between clinical phenotype and the gene mutations was unclear, which suggested the role of additional genetic and epigenetic factors in modifying clinical symptoms.  相似文献   
26.
Summary Primary colon tumors of different sizes and malignancy, chemically induced by methylazoxymethanol in outbred CF-1 mice, were used to investigate the antitumor effects of 5-Fluorouracil (5FU) and cis-diammine-dichloroplatinum (DDP), given weekly i.v. as single agents or in combination. When single-drug chemotherapy was tested, DDP showed higher efficacy than 5FU. In fact, in two separate experiments a significant reduction (P(0.05) of tumor number (TN) and tumor burden was obtained by treatment with the optimal dose of DDP (4.5 mg/kg per injection) and not by that of 5FU (52 mg/kg). When the two drugs were combined (24-h interval), studies carried out on healthy mice treated weekly i.v. showed a lower toxicity with the same doses given in the sequence 5FU-DDP than in the opposite sequence. The two drugs, delivered in the sequence 5FU followed by DDP, statistically reduced the TN and total tumor burden compared to control mice (P(0.05). On the other hand, the same doses in the sequence DDP followed by 5FU did not attain significant tumor reduction. The sequence dependence of the activity and toxicity of the 5FU and DDP combination observed in this experimental model should be taken into account in the design of clinical trials.Abbreviations used MAM methylazoxymethanol acetate - 5FU 5Fluorouracil - DDP cis-diamminedichloroplatinum - TN tumor number - TTB total tumor burden - Ara-C cytosine-arabinoside This work was partially supported by Grant N. 84.00746.44 of Finalized Project Oncology of CNR (Rome, Italy)  相似文献   
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Rheumatoid arthritis (RA) and juvenile rheumatoid arthritis (JRA) are characterized by chronic inflammation, synovial cell proliferation and progressive joint damage. It has been speculated that T cells play an important role in the pathogenesis of RA and JRA in the early stage of the disease. Previous studies have demonstrated discrepant results regarding the significance of T-cell clonality in RA or JRA lesions. It can be postulated that the heterogeneity of these data may be linked to the stage of the disease, as the relative importance of selective immunological events is different during the time from onset to established disease. To avoid this problem, we conducted the present study in nine children affected by JRA at the onset of the disease and before treatment. We analysed the T-cell receptor beta chain variable (TCRBV) of CD4+ and CD8+ lymphocytes in peripheral blood (PBL) and synovial fluid (SFL), by a panel of monoclonal antibodies (MoAbs). Furthermore, to assess the clonotypic pattern of T-cell repertoire, the CDR3 length distribution was evaluated by spectratyping analysis. Our results showed no significant expansion of distinct TCRBV subset in either synovial or peripheral compartments. Conversely, when we studied the CDR3 length distribution, an oligoclonal pattern was found in the SFL of six patients, suggesting the presence of a clonotypic restriction of T cells in SFL, which is not detectable in PBL. These findings are consistent with an antigen driven T-cell expansion sequestered at the inflammatory site.  相似文献   
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