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Bilateral congenital absence of the vas deferens (CAVD) is aform of male sterility (found in otherwise normal men) of unknownaetiology. Because males with cystic fibrosis (CF) almost invariablyhave CAVD as well, we investigated the hypothesis that men withisolated CAVD might share a common genetic background with maleswith CF. Genetic testing for CF was carried out in three generationsof subjects: 44 patients with CAVD and their wives, 24 of theirparents, and 13 of their offspring generated by microsurgicalepididymal sperm aspiration (MESA) and in-vitro fertilization(IVF). DNA extracted from peripheral lymphocytes was amplifiedby the polymerase chain reaction (PCR) and then analysed for12 mutations in the cystic fibrosis transmembrane conductanceregulatory (CFTR) gene. Among 44 patients tested with CAVD,26 (59%) were positive for at least one CF mutation, while thecarrier frequency for CF mutations in the general populationis only 4%. Four patients were found to be compound heterozygotes,three with genotypes Delta F-508/R117H, one with R553X/R117H.Among 24 parents tested, 15 (seven fathers, eight mothers) hadsons with CAVD who were positive for CF mutations. Of these,nine (four fathers and five mothers) were found to be carriersfor CF mutations. These four fathers, although carriers of CFmutations, were obviously fertile. Of the 13 offspring tested,six (three boys and three girls) had CF positive fathers. Ofthese, three (two girls and one boy) were found to be carriersfor CF mutations. These MESA/IVF children are the first offpsringto whom men with CAVD have been able to transmit CF mutations.All of the MESA/IVF male offspring (like their grandfathers)had a normal vas deferens bilaterally, including one carrierfor Delta F-508. This study revealed, by genetic testing ofotherwise normal men with sterility caused by CAVD, a new populationof patients with a variant form of CF and highlighted the possibilitythat carrier frequency for CF is higher than previously thought.Compound heterozygosity for CF mutations and not carrier conditionis associated with isolated CAVD. It is concluded that geneticcounselling and screening for CF should be offered to couplesundergoing sperm aspiration and IVF procedures when CAVD isa factor in their infertility.  相似文献   
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The effect of HIV infection duration and CD4 cell count on short-term CD4 response was evaluated in treatment-naive seroconverters using logistic regression adjusted for CD4 count before highly active antiretroviral therapy (HAART) as well as for exposure category, age, sex, acute infection, and cohort. This association was also investigated in pretreated seroconverters, further adjusting for prior therapy. CD4 response (increase of >100 cells/microL at 6 months) was more likely if HAART was initiated in the first year following seroconversion (OR = 1.50 [95% CI: 1.07-2.10] compared with 2-5 years). There was no improvement in response from initiating HAART with CD4 count >350 cells/microL compared with 201 to 350 cells/microL. Below 200 cells/microL, however, the chance of a CD4 response appeared to be reduced (OR = 0.72 [95% CI: 0.40-1.28] for 0-200 cells/microL compared with 201-350 cells/microL, P = 0.26). Results were similar for pretreated individuals. Further, in pretreated individuals, a CD4 response was less likely if the CD4 nadir was lower than the pre-HAART CD4 count (OR = 0.18 [95% CI: 0.10-0.36] for >150 cells/microL difference between nadir and pre-HAART CD4 count vs. no difference, P < 0.001). Given the limitations of observational studies, particularly the inability to control for unmeasured confounders, these findings suggest that the initiation of HAART within the first year following seroconversion appears to improve short-term immunologic response. After that time, there is little to be gained in terms of short-term response from initiating HAART before reaching a CD4 count of 200 cells/microL.  相似文献   
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BackgroundSubstance use disorders (SUDs) are based on pathophysiological mechanisms common to all psychoactive substances. However, general practitioners (GPs) hold different views depending on the substance in question.ObjectivesTo determine whether the perceptions that teaching GPs and final-year residents in general practice have of patients with a SUD vary according to the substance involved and explore their professional responsibility and management experiences.MethodsA cross-sectional observational study was carried out by asking residents and teaching GPs from eight faculties of medicine about their perceptions, professional responsibility and management experience of patients with tobacco, alcohol and opioid use disorders, using an online questionnaire between June and September 2017.ResultsThe responses of 238 teaching GPs (mean age 50 years SD 3.5; 58% men) and 327 residents (mean age 28 years SD 9.9; 67% women) were analysed (response rates: 9 and 15% respectively). Tobacco smokers were considered to be more responsible for their acts than the other users. Teaching GPs and residents considered that it was their responsibility to discuss substance use. They did not feel able to manage alcohol and opioid use disorders. Tobacco cessation was mainly managed alone (78%). The results were quite similar among teaching GPs and residents.ConclusionThe majority of practitioners had no difficulty managing smoking cessation. During the management of alcohol and particularly opioid use disorders, practitioners did not feel competent. The gap between their perceived responsibility and competencies should be addressed by training and promoting collaborative care.  相似文献   
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BackgroundUse of the single-port da Vinci SP robotic platform for various urological procedures has been described by several groups. However, the comparative performance of the SP robot in relation to earlier models such as the da Vinci Xi is still unclear.ObjectiveTo compare intraoperative and short-term postoperative outcomes between the da Vinci Xi and SP robots for patients undergoing radical prostatectomy (RP) in a referral center.Design, setting, and participantsData were prospectively collected for patients undergoing RP from June 2019 to April 2020 in a single center. The da Vinci SP was used for 71 patients and the da Vinci Xi for 875 patients. After propensity score (PS) matching, two groups of 71 patients were selected for the comparative study.InterventionRP via a transperitoneal approach using the same technique steps and anatomy access with both robot consoles.Outcome measurements and statistical analysisA PS analysis was performed using the covariates age, body mass index, Charlson comorbidity index, Sexual Health Inventory for Men score, American Urological Association symptom score, prostate size, prostate-specific antigen levels, Gleason score, D’Amico risk group, and degree of nerve-sparing. Intraoperative performance and short-term functional (continence and potency) and oncological outcomes were compared between the groups.Results and limitationsMedian follow-up was 4.4 mo (interquartile range [IQR] 1.6–7.2) for the SP group and 3.2 mo (IQR 1.6–4.8) for the Xi group (p = 0.2). The median total operative time and median console time were both significantly higher in the SP group, with median differences of 14 min (95% confidence interval [CI] 9–19) and 5 min (95% CI 0–5), respectively. The proportion of patients with blood loss of >100 ml was significantly lower in the SP group (difference of 27%, 95% CI 12–42%). No intra- or postoperative complications were reported in either group. There were no significant differences in pain scores at 6, 12, and 18 h or in positive surgical margin rates between the groups. The SP group had a significantly higher percentage of extraprostatic extension than the Xi group (difference of 16%, 95% CI 4.6–27%). None of the patients experienced biochemical recurrence during follow-up. The difference in continence rates at 45 d between the SP and Xi groups was 11% (95% CI ?5.6% to 28%) and the difference in potency rates at 45 d was ?7.3% (95% CI ?21% to 6.2%). The short-term follow-up for comparison of functional and oncological outcomes is a limitation.ConclusionsDespite differences in trocar placement and technology between the two da Vinci consoles, the SP has satisfactory intraoperative performance compared to the Xi. SP surgery can be performed safely and effectively during the initial learning phase. However, longer-term follow-up is needed to provide further evidence on the impact of SP implementation on functional and oncological outcomes.Patient summaryWe compared intraoperative and short-term postoperative outcomes for patients who underwent radical prostatectomy using two different robots, the da Vinci Xi and the single-port da Vinci SP. We found that operative time was longer for the Single Port console. Studies with long-term follow-up are needed to compare the functional and oncological outcomes.  相似文献   
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Differing contexts have greatly influenced HTA development in various countries, with considerable effort recently made by international HTA networks (e.g., EUnetHTA) and the European Union (EU) to make HTA a more coherent, equal, and efficient process. Medical devices (MDs) present particular challenges for HTA because of frequent, rapid innovation, outcomes influenced by end-user competence, dynamic pricing and often low-quality scientific evidence. Our objective is to describe the development, structure and governance of a National HTA Program for MDs (PNHTADM) in Italy, a highly participatory, stakeholder-engaged, evidence-based process to reform a fragmented system of appraisal and approval. Based largely on EUnetHTA methods, the resulting process delineates a standardized system for proposing MDs by any stakeholders, accrediting HTA producers, setting criteria for prioritization and appraisals, and innovatively linking recommendations with coverage, reimbursement and procurement of MDs. Expected benefits include reduced disparities in pricing and reimbursement policies and improved access to new technologies across 21 regional healthcare systems in Italy's decentralized, universal system, complete with provisions to require additional evidence collection and centrally monitor diffusion. Though devised for Italy, the design, resources and underlying analysis provide a framework for other nations seeking to consolidate HTA initiatives, particularly in light of new EU regulation.  相似文献   
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Background and Aim: Surgery is not recommended in asymptomatic patients with aortic stenosis (AS). However, prognosis of these patients is worse than retained. We built a simple score (named by the acronym “CAIMAN”) for stratifying asymptomatic patients with AS according to the different risk for cardiovascular events. Material and Methods: Data from 141 patients with moderate‐to‐severe AS followed up for 36 months were analyzed. The end point “outcome” was defined as death of all causes or aortic valve replacement imposed by symptoms or hospital admission for myocardial infarction and/or heart failure. The score was validated in 143 patients prospectively recruited in 2 different centers. Results: The 40 events occurred in the original cohort were associated with higher aortic transvalvular peak jet velocity, calcium score, and observed/predicted left ventricular (LV) mass ratio. Based on the hazard ratios of Cox analysis, the score was calculated as follows: calcium score 1–3 = 1 point, 4 = 6 points; transvalvular peak jet velocity ≤3.6 m/sec = 1 point, 3.6 m/sec = 3 points, observed/predicted LV mass ratio ≤110% = 1 point, >110% = 3 points. After a mean period of 28 ± 18 months, event‐free survival was 18%, 42%, 91%, and 96% in the 4 quartiles of echo score. The accuracy of the score in predicting events was 84% and 77% (P = 0.09) in the original and validation cohort, respectively. Conclusions: The CAIMAN‐ECHO score is a simple and feasible tool useful for an accurate prognostic stratification of patients with asymptomatic moderate‐to‐severe AS.  相似文献   
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