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21.
Adoptive transfer of regulatory T (Treg) cells have been employed effectively for suppression of several animal models for autoimmune diseases. In order to employ Treg cell therapy in patients, it is necessary to generate Treg cells from the patient's own cells (autologous) that would be able to suppress effectively the disease in vivo, upon their reintroduction to the patient. Towards this objective, we report in the present study on a protocol for a successful immune-regulation of experimental autoimmune myasthenia gravis (EAMG) by ex vivo – generated autologous Treg cells. For this protocol bone marrow (BM) cells, are first cultured in the presence of GM-CSF, giving rise to a population of CD11c+MHCII+CD45RA+CD8– DCs (BMDCs). Splenic CD4+ T cells are then co-cultured with the differentiated BM cells and expand to 90% of Foxp3+ Treg cells. In vitro assay exhibits a similar dose dependent manner in the suppression of T effector cells proliferation between Treg cells obtained from either healthy or sick donors. In addition, both Treg cells inhibit similarly the secretion of IFN-γ from activated splenocytes. Administration of 1 × 106 ex-vivo generated Treg cells, I.V, to EAMG rats, modulates the disease following a single treatment, given 3 days or 3 weeks after disease induction. Similar disease inhibition was achieved when CD4 cells were taken from either healthy or sick donors. The disease suppression was accompanied by reduced levels of total AChR specific antibodies in the serum. Moreover, due to the polyclonality of the described Treg cell, we have examined whether this treatment approach could be also employed for the treatment of other autoimmune diseases involving Treg cells. Indeed, we demonstrated that the ex-vivo generated autologous Treg cells suppress Adjuvant Arthritis (AA) in rats.This study opens the way for the application of induced autologous Treg cell therapy for myasthenia gravis, as well as for other human autoimmune diseases involving Treg cells. 相似文献
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对2012年全球上市新药的基本信息,包括通用名、商品名、结构式、CAS号、研发公司、上市国家和主要适应证进行汇总,为新药研发工作者提供参考。 相似文献
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《Indian journal of medical microbiology》2022,40(4):593-595
The performance of enzyme linked immunosorbent assays (EAST) for identifying six indoor allergens was evaluated using skin prick test (SPT) as reference tests in 154 children with allergic rhinitis. Sensitivity of EAST ranged from 9% (cat) to 54% (HDM) with specificity of 74%(cockroach) to 100% (cat) with an agreement ranged from 58 to 86%. Cut off values ?> ?0.35 kU/L showed best sensitivity and specificity. Our findings agree with extant literature which suggests that the ability of EAST to determine the precipitating allergen is moderate. Assays for definitively identifying the inhalant allergen are currently not available. 相似文献
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《Respiratory investigation》2020,58(6):479-487
BackgroundSome patients with sarcoidosis experience worsening of pulmonary lesions. However, no biomarker has been identified that reflects pulmonary disease status in sarcoidosis. We investigated the usefulness of potential markers of pulmonary fibrosis in patients with sarcoidosis.MethodsPlasma matrix metalloproteinase 7 (MMP-7), CC-chemokine ligand 18 (CCL-18), and periostin levels were evaluated in 60 patients with sarcoidosis and 30 healthy controls; bronchoalveolar lavage fluid levels were analyzed in 22 patients with sarcoidosis. To determine the usefulness of these markers, we explored potential correlations between these markers and sarcoidosis clinical characteristics.ResultsPlasma MMP-7, CCL-18, and periostin concentrations were significantly higher in patients with sarcoidosis than those in healthy controls. MMP-7 concentrations in plasma and bronchoalveolar lavage fluid were higher in patients with sarcoidosis with parenchymal infiltration than in those without lung lesions. Moreover, MMP-7 concentration was negatively correlated with pulmonary function.ConclusionAmong these novel biomarkers, MMP-7 most precisely reflected pulmonary sarcoidosis disease status and thus, might be useful for diagnosing and evaluating sarcoidosis, particularly in patients with pulmonary parenchymal lesions. 相似文献
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Spermatogenesis in mammals is a cyclic process of spermatogenic cell development in the seminiferous epithelium that can be subdivided into 12 subsequent stages. Histological staging analysis of testis sections, specifically of seminiferous tubule cross-sections, is the only effective method to evaluate the quality of the spermatogenic process and to determine developmental defects leading to infertility. Such staging analysis, however, is tedious and time-consuming, and it may take a long time to become proficient. We now have developed a Computerized Staging system of Spermatogenesis (CSS) for mouse testis sections through learning of an expert with decades of experience in mouse testis staging. The development of the CSS system comprised three major parts: 1) Developing computational image analysis models for mouse testis sections; 2) Automated classification of each seminiferous tubule cross-section into three stage groups: Early Stages (ES: stages I-V), Middle Stages (MS: stages VI-VIII), and Late Stages (LS: stages IV-XII); 3) Automated classification of MS into distinct stages VI, VII-mVIII, and late VIII based on newly developed histomorphological features. A cohort of 40 H&E stained normal mouse testis sections was built according to three modules where 28 cross-sections were leveraged for developing tubule region segmentation, spermatogenic cells types and multi-concentric-layers segmentation models. The rest of 12 testis cross-sections, approximately 2314 tubules whose stages were manually annotated by two expert testis histologists, served as the basis for developing the CSS system. The CSS system’s accuracy of mean and standard deviation (MSD) in identifying ES, MS, and LS were 0.93 ± 0.03, 0.94 ± 0.11, and 0.89 ± 0.05 and 0.85 ± 0.12, 0.88 ± 0.07, and 0.96 ± 0.04 for one with 5 years of experience, respectively. The CSS system’s accuracy of MSD in identifying stages VI, VII-mVIII, and late VIII are 0.74 ± 0.03, 0.85 ± 0.04, and 0.78 ± 0.06 and 0.34 ± 0.18, 0.78 ± 0.16, and 0.44 ± 0.25 for one with 5 years of experience, respectively. In terms of time it takes to collect these data, it takes on average 3 hours for a histologist and 1.87 hours for the CSS system to finish evaluating an entire testis section (computed with a PC (I7-6800k 4.0 GHzwith 32GB of RAM & 256G SSD) and a Titan 1080Ti GPU). Therefore, the CSS system is more accurate and faster compared to a human histologist in staging, and further optimization and development will not only lead to a complete staging of all 12 stages of mouse spermatogenesis but also could aid in the future diagnosis of human infertility. Moreover, the top-ranking histomorphological features identified by the CSS classifier are consistent with the primary features used by histologists in discriminating stages VI, VII-mVIII, and late VIII. 相似文献
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??OBJECTIVE To optimize the current T cell-E Rose test method, establish a new alternative method, and measure 57 batches of transfer factor preparations using the two methods. METHODS Cell smear was prepared by modified cell smear-dry staining method. Cross-test was performed with fresh porcine thymus and rabbit thymus respectively with sheep erythrocytes. The micro plate-leukocyte adherence inhibition alternative method was established and verified for the linearity, repeatability, and specificity. RESULTS The improved smear-dyeing method had clear and reliable microscopic effect, which was easy to read the preservation. Porcine thymus lymphocytes and rabbit thymus lymphocytes were able to form E rosette with sheep red blood cells, and there was no significant difference between the two methods. The analysis RESULTS of 57 batches of transfer factor injection showed that the leukocyte adherence inhibition rate had no significant difference with the RESULTS of rosette viability. CONCLUSION The improved method can replace the original cell counting plate method, which can better respond to the actual value of the sample with long-term preservation, and it is suitable for reading and reviewing the analysis result of large quantities of samples at any time. The alternative micro plate-leukocyte adherence test method may reduce the human subjective factors, and is more accurate, rapid, reproducible, and specific than the original method, and suitable for high-throughput analysis. 相似文献
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目的:设计并构建针对胰腺癌基因治疗中最关键的靶基因人细胞核因子κB(human NF-κB)的miRNA干扰载体。方法:根据靶基因设计并合成miRNA oligo(引物设计软件),将oligo退火成双链,然后用载体构建试剂盒进行重组克隆,将双链的miRNA oligo插入到miRNA表达载体中,构建miRNA质粒,转化入感受态细胞DH5α,从转化平板分别挑取克隆,用载体通用引物进行菌落PCR筛选,筛选得到的阳性克隆进行测序,以验证重组克隆中插入片段序列是否与设计的oligo序列一致。结果:经过比对,重组克隆中插入片段序列与设计的oligo序列完全一致。结论:成功构建了针对靶基因human NF-κB的miRNA干扰载体,为进一步研究奠定了基础。 相似文献