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1.
目前已用出生免疫错误(IEI)来替代原发性免疫缺陷病这一概念。IEI是一类由单基因突变引起免疫功能异常的遗传性疾病,肝脏和脾脏作为人类重要的免疫器官,与IEI疾病过程中伴发感染、淋巴增殖及自身免疫现象等有重要关联。文章就与IEI相关的肝脾问题进行概述。 相似文献
2.
《Vaccine》2022,40(34):4933-4941
Subunit influenza vaccine only formulated with surface antigen proteins has better safety profiles relative to split-virion influenza vaccine. Compared to the traditional quadrivalent split-virion influenza vaccine, a novel quadrivalent subunit influenza vaccine is urgently needed in China. We completed a phase 3, randomized, double-blind, active-controlled, non-inferiority clinical study at two sites in Henan Province, China. Eligible volunteers were split into four age cohorts (3–8 years, 9–17 years, 18–64 years, and ≥ 65 years, based on their dates of birth) and randomly assigned (1:1) to the subunit and the split-virion ecNAIIV4 groups. All volunteers were intramuscularly administered a single vaccine dose at baseline, and children aged 3–8 years received a boosting dose at day 28. And the immune response was evaluated by measuring hemagglutinin-inhibition antibody titers against the four vaccine strains in blood samples. Safety profiles had nonsignificant differences between the study groups in ≥ 3 years cohort. Most adverse reactions post-vaccination, both local and systemic, were mild to moderate and resolved within 3 days. And no serious adverse events occurred. The immunogenicity of the trial vaccine was non-inferior to the comparator. Further, a two-dose vaccine series can provide better seroprotection than that of a one-dose series in children aged 3–8 years, with clinically acceptable safety profiles.Clinical Trials Registration. ChiCTR2100049934. 相似文献
3.
Naveen Pemmaraju MD Jacqueline S. Garcia MD Andrew Perkins MBBS PhD Jason G. Harb PhD Andrew J. Souers PhD Michael E. Werner PhD Christopher M. Brown PhD Francesco Passamonti MD 《Cancer》2023,129(22):3535-3545
Myelofibrosis is a heterogeneous myeloproliferative neoplasm characterized by chronic inflammation, progressive bone marrow failure, and hepatosplenic extramedullary hematopoiesis. Treatments like Janus kinase inhibitor monotherapy (e.g., ruxolitinib) provide significant spleen and symptom relief but demonstrate limited ability to lead to a durable disease modification. There is an urgent unmet medical need for treatments with a novel mechanism of action that can modify the underlying pathophysiology and affect the disease course of myelofibrosis. This review highlights the role of B-cell lymphoma (BCL) protein BCL-extra large (BCL-XL) in disease pathogenesis and the potential role that navitoclax, a BCL-extra large/BCL-2 inhibitor, may have in myelofibrosis treatment. 相似文献
4.
Lei Yang You-Ling Shi Yan Ma Wei-Wei Ren Guang-Ming Pang Jiao Liu 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2022,130(1):43-52
Krüppel-like factor 16 (KLF16), a member of the Krüppel-like factor (KLF) family, has been extensively investigated in multiple cancer types. However, the role of KLF16 in oral squamous cell carcinoma (OSCC) remains unknown. Thus, we conducted this study to investigate its related mechanism. KLF16 expression in OSCC cell lines was quantified by western blotting. Then, OECM1 and OC3 cells were divided into Blank, siCtrl, siKLF16#1 and siKLF16#2 groups. Subsequently, cell proliferation was detected using 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assays, cell migration and invasion were detected with wound healing and Transwell assays, and cell cycle distribution and cell apoptosis were detected via flow cytometry. KLF16, p21, CDK4, Cyclin D1 and p-Rb expression was detected by western blotting. Finally, xenograft models were established in nude mice to observe the in vivo effects of KLF16 on OSCC. KLF16 protein expression was upregulated in OSCC cells. Compared to the cells in the Blank group, the OECM1 and OC3 cells in the siKLF16#1 group and siKLF16#2 group exhibited a sharp decrease in proliferation but a remarkable increase in apoptosis. Moreover, the proportion of cells in the G0/G1 phase notably increased and that in the S phase decreased, with evident decreases in cell invasion and migration. Moreover, KLF16, cyclin-dependent kinase 4 (CDK4), Cyclin D1 and p-Rb protein expression was upregulated, but p21 expression was downregulated. The mice in the siKLF16#1 and siKLF16#2 xenograft model groups exhibited slower tumour growth and smaller tumours with evident downregulation of Ki67 expression compared to the mice in the Blank group. KLF16 expression was upregulated in OSCC cells, and interfering with KLF16 led to cell cycle arrest, inhibited OSCC cell growth and promoted cell apoptosis. 相似文献
5.
杨姗 《世界科学技术-中医药现代化》2022,24(9):116-125
目的 优化大孔吸附树脂分离纯化血人参总黄酮的工艺条件,研究血人参总黄酮对酪氨酸酶的抑制作用。方法 以吸附率、解吸率等为考察指标,采用静态吸附-解吸试验对6种不同型号的大孔吸附树脂进行筛选,优选最佳的树脂型号。采用单因素试验考察上样液pH、上样液浓度、上样体积、上样体积流量、洗脱溶剂、洗脱液体积流量、洗脱剂体积对血人参总黄酮纯化的影响,确定最佳纯化工艺;以L-酪氨酸、L-多巴为底物,测定血人参总黄酮对酪氨酸单酚酶和二酚酶的抑制作用,并对其抑制机理和抑制类型进行分析。结果 AB-8型大孔吸附树脂对血人参总黄酮的分离纯化效果最好。最佳纯化工艺参数为:上样液pH为4、上样体积为70 mL(4.7 BV)、上样体积流量为1 mL·min-1、上样液浓度为5.38 mg·mL-1、洗脱溶剂为70%乙醇、洗脱剂体积流量为3 mL·min-1、洗脱剂体积为120 mL(8 BV),血人参总黄酮对酪氨酸单酚酶和二酚酶均有抑制作用,其最大半数抑制浓度分别为88.78 mg·L-1和36.46 mg·L-1,对二酚酶的抑制类型为可逆非竞争性抑制。结论 AB-8型大孔吸附树脂可用于纯化血人参总黄酮,纯化后血人参总黄酮的纯度为46.01%,建立的工艺条件稳定可靠。纯化后的血人参总黄酮对酪氨酸酶有抑制作用,抑制类型为可逆非竞争性抑制。 相似文献
6.
7.
目的:探讨脑出血对酵母沉默信息调节因子2(Sirt2)和炎症的影响。方法:将胶原酶Ⅳ注入SD大鼠右侧
纹状体中建立脑出血模型,通过免疫印迹和ELISA 等方法测定大鼠脑出血后48 h 的Sirt2 的表达及炎症变化。利
用Hemin 诱导PC12 细胞损伤模拟体外脑出血模型,并检测Sirt2 及炎症变化;采用短发夹RNA(shRNA)-Sirt2 沉
默Sirt2 在PC12 细胞中的表达及对炎症的影响。结果:手术后48 h 脑出血行为学评分最低。脑出血组Sirt2 的表达
显著高于假手术组。脑出血组IL-6、IL-1β 表达显著升高。结论:脑出血可以促进Sirt2 的表达和炎症反应,降低
Sirt2 的表达可减缓炎症反应。
关键词 脑出血;沉默信息调节 相似文献
8.
目的:研究七氟烷预处理对大鼠骨髓间充质干细胞(MSCs)在缺氧复氧环境下的作用和机制初探。方法:分离培养SD大鼠骨髓间充质干细胞,通过流式细胞仪和诱导分化培养鉴定其免疫表型和分化潜能。细胞随机分为3组:组1空白对照组;组2缺氧复氧组(缺氧24 h,复氧24 h);组3七氟烷预处理组(2%七氟烷预处理2 h后,缺氧24 h,复氧24 h)。处理后收集各组细胞,用流式细胞仪测定其凋亡率,线粒体膜电位变化及细胞周期。Western blot测定细胞外调节蛋白激酶(ERK)的蛋白表达。结果:与组2相比,组3 MSCs凋亡率明显下降,处于S期细胞增多,细胞增殖能力增强。Western blot结果显示:与组2相比,组3磷酸化ERK蛋白表达上升。结论:七氟烷预处理能提高缺氧复氧环境下骨髓间充质干细胞存活率,降低MSCs凋亡数量,并能增强MSCs的增殖能力,这一机制与七氟烷促进MSCs细胞p-ERK蛋白表达相关。 相似文献
9.
Michael Mark Dirk Klingbiel Ulrich Mey Ralph Winterhalder Christian Rothermundt Silke Gillessen Roger von Moos Michael Pollak Gabriela Manetsch Räto Strebel Richard Cathomas 《Clinical genitourinary cancer》2019,17(2):e323-e328
Background
There is evidence linking metformin to improved prostate cancer–related outcomes.Patients and Methods
Twenty-five men with metastatic castration-resistant prostate cancer and prostate-specific antigen (PSA) progression while receiving treatment with abiraterone from 3 Swiss centers were included in this single-arm phase 2 trial between November 2013 and September 2016. Metformin was added to abiraterone continuously at 1000 mg twice daily in uninterrupted 4-week cycles. The primary end point was the absence of disease progression at 12 weeks (PFS12). The Fleming single-stage design was applied. With a 5% significance level and 80% power, 25 patients were required to test PFS12 ≤ 15% (H0) compared to ≥ 35% (H1). Secondary end points included toxicity and safety issues. The study was registered at ClinicalTrials.gov (NCT01677897).Results
The primary end point PFS12 was 12% (3 of 25 patients) (95% confidence interval, 3-31). Most patients had PSA progression, almost half had radiographic progression, but only 1 patient had symptomatic progression. Eleven (44%) of 25 patients had grade 1 and 2 patients each grade 2 (8%) or grade 3 (8%) gastrointestinal toxicity (nausea, diarrhea, loss of appetite). One patient discontinued treatment at week 5 because of intolerable grade 3 diarrhea.Conclusion
The addition of metformin to abiraterone for patients with metastatic castration-resistant prostate cancer and PSA progression while receiving abiraterone therapy does not affect further progression and has no meaningful clinical benefit. A higher-than-expected gastrointestinal toxicity attributed to metformin was observed. 相似文献10.
目的:探讨RG108对人非小细胞肺癌(non-small cell lung cancer, NSCLC)A549和H1299细胞增殖、凋亡的影响及其可能的作用机制。方法:体外培养A549和H1299细胞,经不同浓度RG108处理后,采用MTT法、流式细胞术分别检测细胞增殖率、细胞周期和凋亡水平;qPCR和Western blotting(WB)法检测细胞内TFPI-2 mRNA和蛋白的表达及TMPRSS4的表达量,以甲基化特异性PCR和比色法检测细胞中TFPI-2启动子区域甲基化的状态和程度;分别采用siRNA-TFPI-2和pcDNA3.0-TMPRSS4质粒敲减TFPI-2或过表达TMPRSS4,然后检测细胞增殖率及凋亡率的变化。结果:RG108处理后,A549和H1299细胞的增殖率显著降低(均P<0.05)、细胞周期阻滞于G1/S期(均P<0.05)而凋亡率显著增加(均P<0.01),细胞中TFPI-2 mRNA及蛋白表达水平均显著升高(P<0.01和P<0.05),同时细胞中TFPI-2启动子区域甲基化程度显著降低(均P<0.05)、TMPRSS4的表达也明显减少(P<0.05)。沉默TFPI-2表达后,A549和H1299细胞的增殖水平显著增加(均P<0.05),而转染pcDNA3.0-TMPRSS4质粒则显著降低细胞的凋亡率(均P<0.05)。结论:RG108能够通过抑制TFPI-2甲基化负向调控TMPRSS4表达进而抑制A549和H1299细胞的增殖,并促进其凋亡。 相似文献