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41.
In this article, the possibility of using a Landsat image series to calculate the decadal changes in the area of mountain glaciers in the eastern cordillera of Peru is explored. In the pilot study site, changes in the glacier area at different elevation ranges to understand the altitudinal gradients and the directional properties of glacier retreat during the period 1975–2015 were calculated. This approach can be used in the entire tropical Andes, particularly in the outer tropics, depending on the availability of cloud-free images during the dry season. Similar to other regions in the tropical Andes, glaciers situated below 5000 m a.s.l. have lost nearly 81% of the initial area. It is observed that those glaciers directed towards north-east and east shows higher retreat and this may influence the glacier-fed rivers in the Amazon Basin. Future research will estimate the glacier variations in the entire eastern cordilleras and the corresponding changes in the water discharge volume in the Amazon Basin. 相似文献
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Dovi Stéphanie Acouetey Denis Zmirou-Navier Patrice Avogbe Paul Tossa Thomas Rémen Annick Barbaud José-Antonio Cornejo-Garcia Miguel Blanca Abraham Bohadana Christophe Paris Jean-Louis Guéant Rosa-Maria Guéant-Rodriguez 《Annals of allergy, asthma & immunology》2013,110(6):423-428.e5
BackgroundThe influence of genetic predictors of inflammation and atopy on occupational asthma in apprentices is not known.ObjectivesTo assess the influence of genetic polymorphisms of IL4RA, IL13, TNFA, IL1A, and IL5 on the decline of lung function and bronchial hyperresponsiveness in a prospective follow-up study of baker/pastry maker and hairdresser apprentices.MethodsA total of 351 apprentices were included in the study. We performed skin testing, spirometry, fractional exhaled nitric oxide measurement, and methacholine hyperreactivity testing at the initial visit and during and at the end of the 18-month training period. Gene variants of IL4RA, IL13, TNFA, IL1A, and IL5 were determined in DNA from nasal lavage.ResultsIL13 R130Q/IL4RA S478P or IL13 R130Q//IL4RA Q551R were significant predictors of the decrease of forced expiratory volume and forced vital capacity (P ≤ .006). Genotype GG of TNFAG308A was associated with bronchial hyperresponsiveness in the whole population and in nonatopic individuals (90.63% vs 9.38%; odds ratio, 3.78; 95% confidence interval, 1.10-12.83). TNFA GA and IL5 CC and TNFA GA and IL1A CC were 2 epistatic predictors of exhaled nitrogen monoxide decrease during follow-up (P = .02 and P = .004, respectively). The association with TNFA GA and IL1A CC was the most significant in nonatopic bakers (P < .001).ConclusionWe evidenced a predicting influence of IL13/IL4RA and TNFA in the early exposure to allergens and irritants that precedes occupational asthma. The significance of the associations in the absence of atopy suggests an influence of the genetics predictors related to inflammatory pathways. 相似文献
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Lucely Cetina Tania Crombet Roberto Jiménez-Lima Sergio Zapata Mayra Ramos Sandra Avila Jaime Coronel Eduardo Charco Rafael Bojalil Horacio Astudillo Blanca Bazán Alfonso Due?as-González 《Cancer biology & therapy》2015,16(5):684-689
Nimotuzumab is a humanized IgG1 monoclonal antibody against the EGFR extracellular domain that has been evaluated in solid tumors as a single agent or in combination with chemotherapy and radiation. Cervical cancer patients who are refractory or progressive to first-line chemotherapy have a dismal prognosis, and no second- or third-line chemotherapy is considered standard. This pilot trial aimed to evaluate the efficacy and safety of nimotuzumab in 17 patients with pre-treated advanced refractory or progressive cervical cancer. Nimotuzumab was administered weekly at 200 mg/m2 as single agent for 4 weeks (induction phase), then concurrent with 6 21-day cycles of gemcitabine (800 mg/m2) or cisplatin (50 mg/m2) for 18 weeks (concurrent phase) and then once every 2 weeks (maintenance phase). Nimotuzumab could be continued beyond disease progression. Seventeen patients were accrued and evaluated for safety and efficacy. The median number of nimotuzumab applications was 20 (5–96). The median number of chemotherapy cycles administered was 6 (1-6). No toxicity occurred during induction and maintenance phases (single agent nimotuzumab). In the concurrent phase, grade 3 toxicity events observed were leucopenia, anemia and diarrhea in 11.7%, 5.8% and 11.7% respectively. No complete or partial responses were observed. The stable disease (SD) rate was 35%. The median PFS and OS rates were163 days (95% CI, 104 to 222), and 299 days (95% IC, 177 to 421) respectively. Nimotuzumab is well tolerated and may have a role in the treatment of advanced cervical cancer. 相似文献
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Isabele Rejane de Oliveira Maranhão Pureza André Eduardo da Silva Junior Dafiny Rodrigues Silva Praxedes Laís Gomes Lessa Vasconcelos Mateus de Lima Macena Ingrid Sofia Vieira de Melo Telma Maria de Menezes Toledo Florêncio Nassib Bezerra Bueno 《Clinical nutrition (Edinburgh, Scotland)》2021,40(3):759-766
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Froylan Albarrn-Tamayo Blanca Murillo-Ortiz Roberto Gonzlez Amaro Sergio Lpez Briones 《Archives of Medical Science》2021,17(3):775
IntroductionAging is a natural process involving dysfunction of multiple organs and is characterized by increased susceptibility to infections, cancer and autoimmune diseases. The functionality of the immune system depends on the capacity of lymphocytes to proliferate in response to antigenic challenges, and telomere length has an important role regulating the number of cell divisions. The aim of this study was to determine the possible relationship between telomere length, interleukin 2 (IL-2) production, CD25 expression and proliferation of peripheral blood mononuclear cells (PBMCs) in aged men.Material and methodsTelomere length was measured by RT-PCR in PBMCs from young and aged men. IL-2 production and CD25 expression were determined by ELISA and flow cytometry, respectively. Cell proliferation was measured by CFSE dilution assays upon in vitro stimulation with concanavalin A (Con A).ResultsPBMCs from aged men showed a shorter telomere length and a reduced capacity to proliferate in vitro, compared to young men. In contrast, no significant differences in the level of CD25 expression on T lymphocytes, and in vitro production of IL-2 were detected in both groups. In addition, no significant correlation was detected between levels of CD25 expression, IL-2 production, cell proliferation, and telomere length in aged men.ConclusionsIn aged men the telomere length shortening and the reduced T cell proliferation are not related to the capacity of IL-2 production and CD25 expression on T lymphocytes. 相似文献
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