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排序方式: 共有4655条查询结果,搜索用时 383 毫秒
201.
M Flisiński A Brymora I Bartłomiejczyk E Wiśniewska R Gołda A Stefańska L Pączek J Manitius 《Kidney & blood pressure research》2012,35(6):608-618
Background/Aims: Hypoxia-inducible factor (HIF)-1α is responsible for increased expression of genes engaged in angiogenesis. Our previous study indicated capillary rarefaction and atrophy of glycolytic fibers, mainly in locomotor muscles of uremic animals. Perhaps these changes are secondary to disturbances of HIF-1α in skeletal muscles. Methods: Expression of HIF-1α at mRNA and protein levels, as well as mRNA of vascular endothelial growth factor A (VEGF-A), vascular endothelial growth factor receptor (VEGFR)-1, VEGFR-2, endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS), in gastrocnemius muscle (MG) and longissimus thoracic muscle (ML) were measured by RT-PCR and Western blot. Rats were randomized to subtotal nephrectomy (CKD5/6), uninephrectomy (CKD1/2) or sham operation (controls). Results: For CKD5/6 versus controls, mRNA levels for HIF-1α, VEGF-A, VEGFR-1 and VEGFR-2 were significantly reduced only in MG, while eNOS was significantly decreased and iNOS was significantly increased only in ML. Western blot analysis indicated significantly increased HIF-1α protein levels in MG and ML from CKD1/2 animals versus controls, whereas in the CKD5/6 group, the level of HIF-1α protein decreased significantly in MG and increased significantly in ML versus controls and CKD1/2. Conclusion: The reduced expression of HIF-1α mRNA and protein in locomotor muscle from CKD5/6 animals may be involved in the pathogenesis of uremic myopathy. Increased expression of iNOS in the postural muscles may act as a protective factor through HIF-1α stabilization. 相似文献
202.
Jacek Losy 《Journal of neural transmission (Vienna, Austria : 1996)》2013,120(10):1459-1462
Multiple sclerosis (MS) is characterized by multiple areas of inflammation, demyelination and neurodegeneration. Multiple molecular and cellular components mediate neuroinflammation in MS. They involve: adhesion molecules, chemokines, cytokines, matalloproteases and the following cells: CD4+ T cells, CD8+ T cells, B cells, microglia and macrophages. Infiltrating Th1 CD4+ T cells secrete proinflammatory cytokines. They stimulate the release of chemokines, expression of adhesion molecules and can be factors that cause damage to the myelin sheath and axons. Chemokines stimulate integrin activation, mediate leukocyte locomotion on endothelial cells and participate in transendothelial migration. CD8+ cells can directly damage axons. B cells are involved in the production of antibodies which can participate in demyelination. B cells can also function as antigen presenting cells and contribute to T cell activation. Neuroinflammation is not only present in relapsing–remitting MS, but also in the secondary and primary progressive forms of the disease. The association between inflammation consisting of T cells, B cells, plasma cells and macrophages and axonal injury exists in MS patients including the progressive forms of the disease. The above association does not exclude the possibility that neurodegeneration can exist independently from inflammation. Very little inflammation is seen in cortical MS plaques. Anti-inflammatory therapies with different mode of action change the course of MS. Anti-inflammatory and immunomodulatory treatments are beneficial in the early relapsing stage of MS, but these treatments are ineffective in secondary progressive and primary progressive MS. In the stage of progressive MS, inflammation becomes trapped behind a closed or repaired blood–brain barrier. In such a situation current immunomodulatory, immunosuppressive or anti-inflammatory treatments might not reach this inflammatory process to exert a beneficial effect. 相似文献
203.
Helen M. McTaggart-Cowan Peilin Shi J. Mark FitzGerald Aslam H. Anis Jacek A. Kopec Tony R. Bai 《The Journal of asthma》2013,50(8):630-638
Background. Not taking treatment preferences into account may lead to patients' inappropriate use of asthma treatments. The objective of this study was to quantify these preferences, in terms of risk-benefits trade-offs, for six asthma treatment attributes using a discrete choice experiment (DCE). Methods. Adult asthma patients (n = 157) participated in the study. The custom-designed DCE measured preferences for treatment effectiveness (symptom-free days), potential risk (oral thrush and tremor/heart palpitation), ease of use (frequency of daily administration and number of inhalers required), and cost. A nested logit model was used to determine the relative preferences of each attribute, from which the marginal rates of substitution were calculated. Segmented models were used to test for interactions between cost and treatment benefit with socioeconomic status and medication use. Results. Relationships between preferences and all attributes were in the hypothesized direction. On average, patients were willing to pay an additional $14 per month to receive one additional symptom-free day, and $26, $79, and $112 monthly to avoid one, two, and three annual episodes of oral thrush, respectively. Income and the magnitude of short-acting β -agonist use also affected treatment preferences. Conclusions. Overall, asthma patients desired treatments that offered more symptom-free days, but they were willing to trade days without symptoms in exchange for a reduction in adverse events and greater convenience. 相似文献
204.
Maciej Matciak Jacek Nowacki Włodzimierz Krzymiński 《Oceanological and hydrobiological studies.》2011,40(2):108-111
In this short communication we present the results of field measurements which show the incidence of waters originating from the deeper layers of Puck Bay in shallow Puck Lagoon. The reason for such a situation is the occurrence of a small-scale upwelling. This phenomenon may play a significant role in shaping the ecosystem conditions of Puck Lagoon, which is unique in terms of its natural values. 相似文献
205.
Magdalena Figlerowicz Paulina Jackowiak Piotr Formanowicz Paweł Kędziora Magdalena Alejska Nelli Malinowska Jacek Błażewicz Marek Figlerowicz 《Archives of virology》2010,155(12):1977-1987
Accumulating evidence suggests that certain features of hepatitis C virus (HCV), especially its high genetic variability,
might be responsible for the low efficiency of anti-HCV treatment. Here, we present a bioinformatic analysis of HCV-1a populations
isolated from 23 children with chronic hepatitis C (CHC) subjected to interferon–ribavirin therapy. The structures of the
viral quasispecies were established based on a 132-amino-acid sequence derived from E1/E2 protein, including hypervariable
region 1 (HVR1). Two types of HCV populations were identified. The first type, found in non-responders, contained a small
number of closely related variants. The second type, characteristic for sustained responders, was composed of a large number
of distantly associated equal-rank variants. Comparison of 445 HVR1 sequences showed that a significant number of variants
present in non-responding patients are closely related, suggesting that certain, still unidentified properties of the pathogen
may be key factors determining the result of CHC treatment. 相似文献
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209.
The rapid expansion of biomedical research has brought substantial scientific and administrative data management challenges to modern core facilities. Scientifically, a core facility must be able to manage experimental workflow and the corresponding set of large and complex scientific data. It must also disseminate experimental data to relevant researchers in a secure and expedient manner that facilitates collaboration and provides support for data interpretation and analysis. Administratively, a core facility must be able to manage the scheduling of its equipment and to maintain a flexible and effective billing system to track material, resource, and personnel costs and charge for services to sustain its operation. It must also have the ability to regularly monitor the usage and performance of its equipment and to provide summary statistics on resources spent on different categories of research. To address these informatics challenges, we introduce a comprehensive system called MIMI (multimodality, multiresource, information integration environment) that integrates the administrative and scientific support of a core facility into a single web-based environment. We report the design, development, and deployment experience of a baseline MIMI system at an imaging core facility and discuss the general applicability of such a system in other types of core facilities. These initial results suggest that MIMI will be a unique, cost-effective approach to addressing the informatics infrastructure needs of core facilities and similar research laboratories. 相似文献
210.