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51.
心脏直视手术围术期自体血回输335例的监护   总被引:2,自引:0,他引:2  
0 引言 自体输血是采集患者体内血或回收自体失血,再输回同一患者,献血者与受血者为同一个体,既可以节约临床用血,减少患者费用,更重要是可以避免或减少同种输血传播感染性疾病.我科对335例体外循环心内直视手术患者实行自体血回输,收到较好的社会效益和经济效益.1 临床资料 1998-09/1999-02,我科心脏直视手术共445例,围术期采用自体输血335例,其中先心病226例,瓣膜手术59例,复杂心内畸形37例,冠心病、大血管13例,占同期体外循环心内直视手术75%.患者主要适应证:心脏及大血管外科手术,术前一般情况尚好,无肝、肾、呼吸功能障碍;术前检查…  相似文献   
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The American Board of Family Practice (ABFP) is developing a computer-based testing system that will create realistic clinical encounters using an adaptation of an item generation process. Simulated patients' entire lives will be stochastically produced from a knowledge base, with constraints applied to prevent implausible simulations. The constraint mechanisms include knowledge acquisition decisions about grouping closely related medical concepts and widespread use of Bayesian networks to manage dependencies between concepts. Bayesian networks and fuzzy definitions provide stochastic variability between simulations produced from the same data. Examinees will interact with these patients using a large and stable set of queries and interventions. Multiple management plans associated with patient simulations provide a framework for scoring performance. All major components, including Health States, history generating "Lead To" objects, and Plans are reusable and often substitutable. Although initial knowledge acquisition demands are enormous, the system has good potential for low cost maintenance of content areas, and economies of scale as simulations and components are reused.  相似文献   
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Measurement of treatment costs is important in the evaluation of medical interventions. Accurate cost estimation is problematic, when cost records are incomplete. Methods from the survival analysis literature have been proposed for estimating costs using available data. In this article, we clarify assumptions necessary for validity of these techniques. We demonstrate how assumptions needed for valid survival analysis may be violated when these methods are applied to cost estimation. Our observations are confirmed through simulations and empirical data analysis. We conclude that survival analysis approaches are not generally appropriate for the analysis of medical costs and review several valid alternatives.  相似文献   
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Summary The cortical imaging technique (CIT), a mathematical method for simulating the potential fields on the surface of the brain, was used to analyze the spatio-temporal progression of the AEP P300 component (as well as the preceding and subsequent N2a and N3 components) from thirty normal adult subjects recorded in a standard oddball paradigm. Comparisons were made between the progressions of the endogenous event-related cognitive potentials and the exogenous stimulus-dependent potentials (Nl component). Cortical imaging results suggest that different and multiple generator sites are involved in the production of exogenous and endogenous evoked responses. We particularly note the asymmetric development of the P300 component and the apparent anterior generator sites for the N2a component. This last result is interesting because the N2a precedes the P300 component and supports an earlier frontal contribution.  相似文献   
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OBJECTIVE: Anatomic patency after percutaneous transluminal angioplasty (PTA) of the superficial femoral and popliteal arteries does not guarantee clinical success. The aim of this report is to determine the causes of clinical failure after PTA. METHODS: The records of all patients who have undergone PTA of the femoropopliteal arterial segment by our vascular group were retrospectively reviewed. Only patients with complete records and at least one postprocedure clinical and anatomic assessment within the same 30-day time interval were included. Success was defined according to the Society for Vascular Surgery/International Society for Cardiovascular Surgery Ad Hoc Subcommittee on Reporting Standards for Endovascular Procedures. Anatomic cumulative patency and clinical success were calculated according to life table analysis on an intent-to-treat basis. RESULTS: We identified 85 patients who met inclusion criteria. We treated 112 lesions with an average stenosis of 80% +/- 16% and lesion length of 2.3 +/- 1.8 cm. Technical failure occurred in six (5.4%) of 112 lesions. Cumulative clinical success was 69% at 1 year, 54% at 2 years, 49% at 3 years, and 40% at 4 years. Anatomic patency was 74% at 1 year, 62% at 2 years, 57% at 3 years, and 52% at 4 years. There were 45 clinical failures; of these, twenty-seven (60%) occurred in conjunction with anatomic failure. Anatomic failure was due to restenosis in 12 patients (44%), occlusion in eight patients (30%), and restenosis with progression of disease in six patients (22%). Anatomic failure at the time of the procedure occurred in one patient (4%). Clinical failure occurred despite anatomic patency in the remaining 18 patients (40%). Etiology for clinical failure in this latter group included progression of disease within the treated vessel in 12 patients (67%), iliac disease in three patients (17%), tibial disease in two patients (11%), and bypass graft failure in one patient (5%). Fifty percent of all 45 clinical failures were successfully treated with supplemental percutaneous procedures. CONCLUSION: A PTA is an acceptable therapeutic option for the treatment of focal occlusive disease of the femoropopliteal arterial segment. Most clinical failures were due to anatomic failure, but a significant number occurred despite patency at the PTA site. Although primary clinical success rates were inferior to surgical bypass graft, supplemental PTA was possible in 50% of patients. Repeat percutaneous treatment may extend the interval of clinical success and may obviate the need for surgical bypass graft.  相似文献   
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OBJECTIVE: To describe an effective technique for mastoid cavity obliteration in canal wall down tympanomastoidectomy for chronic otitis media and review its efficacy in producing a dry, low-maintenance, small mastoid cavity. DESIGN:: Retrospective clinical study of a consecutive series of procedures from 1995 to 2000. SETTING: Tertiary referral center and institutional academic practice in otology and neurotology. PATIENTS: Sixty consecutive procedures for active chronic otitis media with a minimum follow-up of 12 months (mean, 31 mo; range, 12-80 mo). INTERVENTION: All patients had canal wall down mastoidectomy with simultaneous tympanoplasty including split-thickness skin grafting. An inferiorly pedicled, periosteal-pericranial flap was used in conjunction with autologous bone pate to obliterate the mastoid cavity. The additional length provided by the pericranial extension of the flap permitted it to reach superior to the lateral canal and into the sinodural angle, with improved coverage of bone pate and better reduction of cavity size. OUTCOME MEASURES: The primary outcome measure was control of suppuration and creation of a dry, low-maintenance mastoid cavity, which was assessed using a previously developed semiquantitative scale. This scale includes a temporal dimension to assess control of infection. Secondary outcome measures included postoperative complications (i.e., hematoma, infection, flap necrosis, and meatal stenosis) and incidence of recurrent or residual cholesteatoma. RESULTS: Forty-nine ears (82%) maintained a small, dry, healthy mastoid cavity. Five ears (8%) had intermittent otorrhea easily controlled by topical treatment. Six ears (10%) had suboptimal control of otorrhea, of which four had meatal stenosis. There were no residual or recurrent cholesteatomas. Outcomes remained stable over progressively longer follow-up, up to 80 months. CONCLUSION: Obliteration of a canal wall down mastoid cavity by a postauricular periosteal-pericranial flap with autologous bone pate is a reliable and effective technique that results in a dry, trouble-free mastoid cavity in 90% of patients with active chronic otitis media.  相似文献   
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