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21.
病理性近视眼的研究进展 总被引:5,自引:4,他引:1
通过复习近年来相关文献,对近视眼发生发展机制与形觉剥夺之间的关系进行综合评述。认为近视眼的发生及眼轴延长与形觉剥夺有一定关系,深入研究其相关机制,对近视眼的早期防治具有重要意义。 相似文献
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23.
Dong-Hai Xiong Hui Shen Peng Xiao Yan-Fang Guo Ji-Rong Long Lan-Juan Zhao Yao-Zhong Liu Hong-Yi Deng Jin-Long Li Robert R Recker Hong-Wen Deng 《Journal of bone and mineral research》2006,21(3):424-437
A genome-wide screen was conducted using a large white sample to identify QTLs for FNCS geometry. We found significant linkage of FNCS parameters to 20q12 and Xq25, plus significant epistatic interactions and sex-specific QTLs influencing FNCS geometry variation. INTRODUCTION: Bone geometry, a highly heritable trait, is a critical component of bone strength that significantly determines osteoporotic fracture risk. Specifically, femoral neck cross-sectional (FNCS) geometry is significantly associated with hip fracture risk as well as genetic factors. However, genetic research in this respect is still in its infancy. MATERIALS AND METHODS: To identify the underlying genomic regions influencing FNCS variables, we performed a remarkably large-scale whole genome linkage scan involving 3998 individuals from 434 pedigrees for four FNCS geometry parameters, namely buckling ratio (BR), cross-sectional area (CSA), cortical thickness (CT), and section modulus (Z). The major statistical approach adopted is the variance component method implemented in SOLAR. RESULTS: Significant linkage evidence (threshold LOD = 3.72 after correction for tests of multiple phenotypes) was found in the regions of 20q12 and Xq25 for CT (LOD = 4.28 and 3.90, respectively). We also identified eight suggestive linkage signals (threshold LOD = 2.31 after correction for multiple tests) for the respective geometry traits. The above findings were supported by principal component linkage analysis. Of them, 20q12 was of particular interest because it was linked to multiple FNCS geometry traits and significantly interacted with five other genomic loci to influence CSA variation. The effects of 20q12 on FNCS geometry were present in both male and female subgroups. Subgroup analysis also revealed the presence of sex-specific quantitative trait loci (QTLs) for FNCS traits in the regions such as 2p14, 3q26, 7q21 and 15q21. CONCLUSIONS: Our findings laid a foundation for further replication and fine-mapping studies as well as for positional and functional candidate gene studies, aiming at eventually finding the causal genetic variants and hidden mechanisms concerning FNCS geometry variation and the associated hip fractures. 相似文献
24.
The effects of combined use of earthworm extract(912)and HpD-laser on the produc-tion of reactive oxygen and the biosynthesis of DNA in S_(180) tumor cells were studied throughchemiluminescence measurement and[~3H]-TdR incorporation assay.The results showed that as com-pared with the control,the intensity of chemiluminescence emitted by tumor cells treatedsimultaneously with 912 and HpD-laser was enhanced more than ten-folds,while that treated with912 or HpD-laser alone was increased only 2~4 folds.The[~3H]-TdR incorporation into tumorcells of the former group was inhibited upto 74.1%,and that of the latter groups decreased onlyby 42.2% and 40.0%,respectively.In accordance with these biochemical changes,the ultrastructuraldamage of tumor cells of the former,combinedly treated group appeared to be the most serious.This suggests an additive effect of 912 with HpD-laser on tumor cells.In addition,if free radicalscavengers,such as catalase and superoxide dismutase,were added to the reaction systembefore chemiluminescence assay,the luminescent enhancement effect mentioned above was dramaticallyalleviated,implying the presence of O_2~ and H_2O_2 in the system.Therefore,as to the toxic effecton tumor cells,912 and HpD-laser are not only additive in efficiency,but also similar in theunderlying mechanism of action. 相似文献
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26.
郭永建 《福建医科大学学报》1994,(1)
采用间接ELISA检测23名肾移植受者血清巨细胞病毒(CMV)抗体,共检出18名(78%)活动性CMV感染,其中10名(44%)为原发性感染。结果证实CMV-IgE和-IgA具有较好的血清学诊断价值,优于CMV-IgM。 相似文献
27.
Tumors from 40 patients and 7 established human xenograft tumor lines were grown in three-dimensional histoculture. A Viable-Cell-Index (VCI) based on fluorescent dyes and Growth Fraction Index (GFI) based on [3H]thymidine incorporation were measured by confocal microscopy and histological autoradiography, respectively, after treatment with cytotoxic agents. Chemosensitivity in vitro with the two methods was correlated with chemosensitivity of the same set of human xenografted tumor lines grown in nude mice. The percent accuracy of in vitro to in vivo correlation with VCI (73%) was higher than GFI (63%). The number of false positives with VCI was 12.1% (4/33), and with GFI was 31.3% (10/32). The results thus indicated that in vitro histoculture with fluorescent vital-dye end-points to measure cell viability is of potential use to determine tumor chemosensitivity. 相似文献
28.
吴国娟 《临床心身疾病杂志》2003,9(3):166-167
目的 了解司法鉴定中精神病患者反复上访原因。方法 对诊断为无精神病者与诊断为精神病偏执型人格障碍、偏执性精神病、精神分裂症者的上访诱因、动机、目的、内容、时间、形式、有否过激行为等进行比较。结果 上访诱因、动机、目的等方面以生活、工作、经济问题为主;上访时间以患病5—20a者居多。共33例(71.73%):上访者中有过激行为者21例(45.65%)。结论 精神病患者上访者中以偏执型人格障碍、偏执性精神病、精神分裂症居多。其特点与正常人有所区别。这就要求政府部门在接待上访者及处理上访问题时。应加以严格区分并正确、合理解决上访要求。以免产生不良的社会问题。 相似文献
29.
基因芯片快速HLA-DR52组分型 总被引:3,自引:0,他引:3
目的 用基因芯片对HLA-DR52组快速分型。方法 根据中国汉族人群常见的HLA-DRB位点及其基因多态性的独特序列,设计特异性的寡核苷酸分型探针,制成寡核苷酸芯片。通过组间特异引物扩增基因组DNA,扩增中用荧光标记,扩增标记后的产物与芯片的探针杂交,通过杂交产生的荧光信号确定样品的基因亚型。83份样本分别用基因分型芯片和序列特异性引物聚合酶链反应技术(PCR-SSP)对HLA-DR52组分型。结果PCR-SSP分型DR52组57个位点中,经芯片分型有2个无DR52组位点,3个PCR-SSP分型为DR52组纯合子,芯片为DR52组杂合子,1个PCR-SSP分型为非DR52组纯合子,芯片分型为含有1个DR52组位点的杂合子。结论 基因芯片能对HLA-DR52组快速、准确的分型,比PCR-SSP能更多的检出DR52组位点,特别是能将纯合子进一步分型,适合临床应用。 相似文献
30.
目的 :探讨经肝动脉介入治疗并发胆囊坏死的发生原因和防治措施。方法 :报告 2例经肝动脉介入治疗并发胆囊坏死的病例 ,均经手术病理证实。并结合文献资料分析这一并发症发生的机率、原因 ,以及为了减少并发症的发生需要注意的一些问题。结果 :近 8年来我院共做经肝动脉介入治疗 6 80例次 ,并发胆囊坏死 2例 (0 3% )。其发生原因是多方面的。超选择插管不到位是该并发症发生的主要原因。结论 :胆囊坏死是经肝动脉介入治疗比较常见的严重并发症之一 ,在今后工作中应引起足够的重视 ,尤其对肝血管瘤的介入治疗更应慎重 ,使这一并发症的发生率降至最低限度。 相似文献