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11.
Patrizio Pasquale; Asch Ricardo H.; Handelin Barbara; Silber Sherman J. 《Human reproduction (Oxford, England)》1993,8(2):215-220
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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Cytomegalovirus (CMV) is a well-known cause of disease occurring after bone marrow transplantation (BMT). The manifestations of CMV range from asymptomatic infection, defined as active CMV replication in the blood in the absence of clinical manifestations or organ failure abnormalities, to CMV disease, characterized by CMV infection with clinical symptoms or organ function abnormalities. Diagnostic procedures to assess the viral load have improved greatly with the increased use of antigenemia, CMV DNA, and immediate early-messenger RNA. Many conditions concur in determining the risk of developing CMV reactivation or disease after bone marrow transplant with serologic status of donor and recipient, type of bone marrow transplant, presence of graft-versus-host disease being the most studied. However, time and quality of immune reconstitution seems to be the pivotal factors. Pneumonia and gastrointestinal involvement are the most frequently documented clinical pictures with late-onset CMV reactivation or disease representing a new challenge. CMV prophylaxis or pre-emptive therapy adopted during the last few years in allogeneic BMT recipients has changed the natural history of the disease, reducing the risk of CMV disease, CMV-associated death, transplant-related mortality, and has prolonged the period at risk. Specific studies on children are lacking, however, the clinical pictures and features seems to be similar both in children and adults. 相似文献
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Babiker A Darbyshire J Pezzotti P Porter K Prins M Sabin C Walker AS;CASCADE Collaboration 《Journal of acquired immune deficiency syndromes (1999)》2003,32(3):303-310
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
15.
Marie Rouillon Catherine Laporte Pierre Ingrand Philippe Castra Paolo Di Patrizio Nassir Messaadi Philippe Binder Julie Dupouy 《The European journal of general practice》2021,27(1):77
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
16.
Rosanna Tarricone Fabio Amatucci Patrizio Armeni Helen Banks Ludovica Borsoi Giuditta Callea Oriana Ciani Francesco Costa Carlo Federici Aleksandra Torbica Marcella Marletta 《Health policy (Amsterdam, Netherlands)》2021,125(5):602-608
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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Lawrence G. Rudski Luna Gargani William F. Armstrong Patrizio Lancellotti Steven J. Lester Ekkehard Grünig Michele DAlto Meriam ?str?m Aneq Francesco Ferrara Rajeev Saggar Rajan Saggar Robert Naeije Eugenio Picano Nelson B. Schiller Eduardo Bossone 《Journal of the American Society of Echocardiography》2018,31(5):527-550.e11