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51.
OBJECTIVE: Our purpose was to assess the incremental effect of maximum-intensity-projection (MIP) image processing on the ability of various observers to detect small (<1 cm in diameter) central and peripheral lung nodules revealed by multidetector CT. MATERIALS AND METHODS: We retrospectively identified 25 patients with metastatic disease, each having from two to nine nodules that were 3-9 mm in diameter. Two senior and three junior reviewers interpreted all images on a workstation. The observers first reviewed axial images (3.75-mm collimation, 3-mm reconstruction interval, multidetector acquisition) in cine and sequential fashion and recorded the size, lobe, and central or peripheral (within 1 cm of the edge of lung) location of each nodule. MIP images (10-mm slab, 8-mm interval) were then reviewed, and additional nodules detected were recorded. Final counts were established by consensus. RESULTS: The reviewers found 122 nodules (71 peripheral, 51 central) in the 25 patients. The addition of MIP slabs significantly enhanced reviewer detection of central nodules (p < 0.001) and junior reviewer detection of peripheral nodules (p < 0.001). MIP slabs also reduced the effects of reviewer experience, particularly for peripheral nodules. CONCLUSION: MIP processing reduces the number of overlooked small nodules, particularly in the central lung. Observer nodule detection remains imperfect even when lesions are clearly depicted on images.  相似文献   
52.
This case report illustrates atypical magnetic resonance (MR) imaging findings in a liver hemangioma mimicking a malignant lesion—lower signal intensity than cerebrospinal fluid on T2-weighted spin-echo images and lack of early enhancement on dynamic contrast material—enhanced gradient-echo images. Pathologic analysis demonstrated nearly total replacement of the vascular cavities by dense fibrous tissue. In this rare, sclerosed form, this lesion could not be defined as a hemangioma with MR imaging.  相似文献   
53.
Testosterone deficiency seems to impair the clinical response to phophodiesterase-5 (PDE-5) inhibitors in patients with erectile dysfunction (ED). In hypogonadal men, testosterone repletion was associated with enhanced sexual function in patients who failed initial treatment with sildenafil or tadalafil. We conducted a systematic review of studies that evaluated combination therapy of testosterone and PDE-5 inhibitors in patients with ED and low, low-normal testosterone levels who failed monotherapy. The studies we examine are heterogeneous with several methodological drawbacks and that, overall, the addition of testosterone to PDE-5 inhibitors might benefit patients with ED associated with testosterone <300 ng/dL (10.4 nmol/L) who failed monotherapy. Further studies, with a randomized placebo-controlled and double blind design, are needed to describe the appropriate target patient group, testosterone cut-off and to define the optimal dose and duration of combination therapy.  相似文献   
54.
Osteoporosis may be a lifelong condition. Robust data regarding the efficacy and safety of both long-term osteoporosis therapy and therapy discontinuation are therefore important. A paucity of clinical trial data regarding the long-term antifracture efficacy of osteoporosis therapies necessitates the use of surrogate endpoints in discussions surrounding long-term use and/or discontinuation. Long-term treatment (beyond 3-4 years) may produce further increases in bone mineral density (BMD) or BMD stability, depending on the specific treatment and the skeletal site. Bisphosphonates, when discontinued, are associated with a prolonged reduction in bone turnover markers (BTMs), with a very gradual increase to pretreatment levels within 3 to 60 months of treatment cessation, depending on the bisphosphonate used and the prior duration of therapy. In contrast, with nonbisphosphonate antiresorptive agents, such as estrogen and denosumab, BTMs rebound to above pretreatment values within months of discontinuation. The pattern of BTM change is generally mirrored by a more or less rapid decrease in BMD. Although the prolonged effect of some bisphosphonates on BTMs and BMD may contribute to residual benefit on bone strength, it may also raise safety concerns. Adequately powered postdiscontinuation fracture studies and conclusive evidence on maintenance or loss of fracture benefit is lacking for bisphosphonates. Similarly, the effects of rapid reversal of bone turnover upon discontinuation of denosumab on fracture risk remain unknown. Ideally, studies evaluating the effects of long-term treatment and treatment discontinuation should be designed to provide head-to-head "offset" data between bisphosphonates and nonbisphosphonate antiresorptive agents. In the absence of this, a clinical recommendation for physicians may be to periodically assess the benefits/risks of continuation versus discontinuation versus alternative management strategies.  相似文献   
55.
Objectives. – To assess the test-retest reliability and the construct validity of a modified version of the Lequesne index.Methods. – Patients with symptomatic knee osteo-arthritis fulfilling the revised criteria of the american college of rheumatology completed the Lequesne index twice at a 3 h interval. Impairment outcome measures and patients’ perceived discomfort in walking and handicap were recorded. An item by item analysis was performed. Items having insufficient psychometric properties were excluded. Test-retest reliability was assessed using the intraclass correlation coefficient (ICC) and the Bland and Altman method. Construct validity was investigated using Spearman rank correlation coefficient and a factor analysis was performed.Results. – Eighty-eight patients were included. One question assessing pain (question IE) had a weak reliability (Kappa = 0.39) and was excluded. The test-retest reliability of the modified questionnaire was excellent (ICC = 0.95). Expected convergent and divergent correlations were achieved excepted for Vas pain and Vas handicap (0.46 and 0.40 respectively), and the “a priori” double stratification was confirmed by factor analysis, explaining 48.7% of the variance.Conclusion. – The modified form of the Lequesne index has sufficient psychometric properties to be used to assess pain and function in knee osteo-arthritis in a french population.  相似文献   
56.
OBJECTIVE: The objective of this study was to assess improved myocardial protection by performing coronary artery bypass grafting (CABG) on the beating heart. A case-matched study was conducted among patients who underwent CABG either on-pump (group 1), or off-pump (group 2). METHODS: Forty-five pairs of patients, having a similar clinical profile, were selected on the basis of five variables: age, gender, body surface area, ejection fraction, extent of coronary disease. Operative risk predicted by the The Society of Thoracic Surgeons national database was 1.80+/-0.35% in group 1, and 1.89+/-0.37% in group 2 (NS). Cold blood cardioplegia and 28 degrees C cardiopulmonary bypass were used in group 1. In group 2, beating heart coronary grafting was achieved with the Octopus 1 and 2 stabilizers. The average number of distal anastomoses was 2.8+/-0.1 in group 1 and 2.3+/-0.1 in group 2 (P=0.015). RESULTS: There was no significant difference among the groups regarding the trend in cardiac index, left and right ventricular stroke work indexes, and systemic and pulmonary vascular resistance indexes. However, heart rate trend was slower in group 2 (P=0.05). Pharmacological support was required in 65% of the patients in group 1, and in 33% in group 2 (P<0.001). The total amount of Dobutamine and/or Dopamine administered during the first 48 h was 3914+/-1306 gamma/kg in group 1 and 1645+/-697 gamma/kg in group 2 (P=0.049). Release of creatine kinase MB mass isoenzyme (CK-MB mass) was markedly reduced in group 2 (P<10(-4)). CONCLUSIONS: Hemodynamic outcome following off-pump CABG is similar to on-pump CABG but the need for inotropic support is significantly reduced and CPK-MB mass release is markedly lower.  相似文献   
57.
Facial lipodystrophies are characterized by a progressive atrophy of the subcutaneous fat of the face. The aim of our study, which includes two types of facial lipodystrophy (Barraquer–Simons (BS) and Parry–Romberg (PR) syndromes), was to compare the results of treatment with lipofilling and with free flaps and to evaluate the long-term outcome. Eighteen patients (seven cases of BS and 11 cases of PR), issued from four different plastic surgery departments, underwent surgery from 1986 to 2004. The average follow-up period was 5.25 years. Of seven patients who had free flap surgery, four presented satisfying results and three bad results. Dissatisfaction in this group was mainly due to ptosis and a partial atrophy of the flaps. Three good and nine excellent results were seen in patients treated with lipofilling. The results in this group were technique-related, with the nine patients treated with lipostructure (Coleman’s technique) presenting the best outcome. Lipofilling, as an alternative of free flaps, seems to offer superior results. This technique is simple, not expensive, and minor compared to free tissue transfer. It allows the treatment of two areas in one-stage procedure without leaving scars. Lipostructure fills all the conditions to become the technique of choice in the treatment of facial lipodystrophies.  相似文献   
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The absorption of bisphosphonates from the gut is poor. The question arises whether the absorption of alendronate, and thus its bioavailability, is further altered by the local inflammatory process in patients with Crohns disease, thereby potentially affecting clinical outcome when used in the treatment of osteoporosis. To address this question, urinary excretion of alendronate was evaluated 3 months and 6 months after start of treatment with oral alendronate at a dose of 10 mg/day in 19 osteoporotic patients with stable Crohns disease, 12 of whom had an intestinal resection. Biochemical parameters of bone turnover and BMD were also measured at start and at 6 months. Thirteen patients had been previously treated with glucocorticoids and five were currently using them. The average 24-h urinary excretion of alendronate was 0.5–0.6% of the dose administered, a figure comparable to that reported for osteoporotic patients without gut pathology. There was a significant decrease from baseline in urine N-telopeptides of collagen cross-links (NTx)/creatinine (60%) associated with an increase in lumbar spine BMD of already 2% after 6 months of treatment. Our data suggest that in patients with Crohns disease, alendronate is adequately absorbed from the intestine and retained in the skeleton. This adequacy is confirmed by appropriate suppression of bone resorption and increase in lumbar spine BMD. These data hold significant implications for the clinical management of patients with Crohns disease and osteoporosis.  相似文献   
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