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目的 探讨西藏地区农、牧民生活习俗与包囊虫病的关系。方法 自制问卷对 7个县 2 40个家庭 163 1名成员与包囊虫感染有关的生活习俗进行调查分析。结果 饭前便后洗手的人仅有 16 1%,餐具一般都用天然水洗 ,大部家庭用天然绵羊绒擦洗茶具。大多数人都喝过河溪水 ,池塘水 ,人人都吃半生不熟的肉 ,半数以上的吃生肉和生血肠 ,绝大多数人喝未经消毒的鲜牛、羊奶。 10 0 %家庭养狗 ,所有人员与狗、羊、牛、马接触密切。包囊虫病人占调查人数 0 43 %( 7/ 163 1) ,有典型症状者占 0 67%( 11/ 163 1)。结论 当地居民感染包囊虫与不良生活习俗有关 相似文献
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OBJECTIVE: To examine the oxidation or reduction products in patients with rheumatism arthritis (RA), and investigate the relationship between oxidation or reduction products and occurrence and development of RA. METHODS: The serum levels of total ascorbic acid (TAA), dehydroascorbic acid (DHAA)/TAA, vitamin E, advanced oxidation protein products (AOPP) and malondialdehyde (MDA) were detected by high-performance liquid chromatography with electrochemical detection in 83 RA patients and 30 healthy adults. Correlation analysis of AOPP, MDA and hs-CRP was performed. RESULTS: Compared with normal control group, significantly higher serum MDA, DHAA/TAA, and AOPP levels were detected in RA patients (P<0.05), but vitamin E showed no significant difference (P<0.05). Linear regression analysis showed that MDA (P<0.01) was positively but AOPP (P>0.05) negatively correlated to hs-CRP. CONCLUSIONS: Oxidation or reduction products in serum of RA patients increases significantly, which may be an important mechanism for the occurrence and development of RA. Serum AOPP and MDA levels can reflect the oxidation status in RA patients. 相似文献
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OBJECTIVE: To observe the morphological changes of Balb/C mouse embryonic stem cells following directed differentiation into pancreatic islet-like cell clusters (PICC) in vitro using atomic force microscope (AFM). METHODS: Balb/C mouse embryonic stem cells were first cultured into embryonic bodies (EBs) and allowed to differentiate spontaneously for 4 days. The cells were then transferred to gelatin-coated dishes for the EBs to attach and spread on the tissue culture plates, in the course of which a series of cell growth factors such as basic fibroblast growth factor (bFGF), insulin-like growth factor 1 (IGF-1) and nicotinamide were added into the culture medium at specific time points to induce directed differentiation of the stem cells into PICC. Immunocytochemistry was employed to detect the cells positive for insulin and glucagon, which were observed with AFM. RESULTS: The embryonic stem cells developed into cell clusters of different sizes, in which the cells were tightly arranged. Islet B cells were numerous in the center of clusters and darkly stained, but fewer in the peripherals with lighter stains. Islet A cells expressing glucagon were relatively fewer in the cell clusters, found mainly in the peripherals. Scanning of the insulin-positive clusters by AFM revealed large quantity of tissue fibers resembling nerve fibers that formed a reticular structure in disorderly arrangement. Numerous round granules were observed in the cytoplasm of almost identical sizes ranging from 0.5 to 1.0 mum in diameter. CONCLUSION: The cell clusters obtained by directed differentiation are mature in both morphology and function with also well organized structures. 相似文献
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凋亡素原核表达载体的构建和表达 总被引:2,自引:0,他引:2
目的 构建凋亡素原核表达系统,以制备抗原物质凋亡素融合蛋白。方法 通过PCR方法,以pcDNA-VP3质粒为模板,扩增出凋亡素VP3基因。将其克隆到原核表达载体pET-DsbA的多克隆位点,构建成凋亡素的高效原核表达栽体pET-DsbA-VP3,将该质粒转化到大肠杆菌E.coliBL21(DE3)plysS中,以异丙基硫代-β-D-半乳糖苷(isopropylthio-β-D-galactoside,IPTG)对其进行诱导表达,聚丙烯酰胺凝胶电泳分析目的蛋白。结果 转化有凋亡素原核表达载体pET-DsbA-VP3的大肠杆菌E.coliBL21(DE3)plysS经IPTG诱导后,聚丙烯酰胺凝胶电泳出现38300的目的蛋白条带。结论 凋亡素原核表达栽体pET-DsbA-VP3能高效表达出凋亡素融合蛋白。 相似文献
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Kristy E Bailey Danny L Costantini Zhongli Cai Deborah A Scollard Zhuo Chen Raymond M Reilly Katherine A Vallis 《Journal of nuclear medicine》2007,48(9):1562-1570
(111)In-DTPA-human epidermal growth factor ((111)In-DTPA-hEGF [DTPA is diethylenetriaminepentaacetic acid]) is an Auger electron-emitting radiopharmaceutical that targets EGF receptor (EGFR)-positive cancer. The purpose of this study was to determine the effect of EGFR inhibition by gefitinib on the internalization, nuclear translocation, and cytotoxicity of (111)In-DTPA-hEGF in EGFR-overexpressing MDA-MB-468 human breast cancer cells. METHODS: Western blot analysis was used to determine the optimum concentration of gefitinib to abolish EGFR activation. Internalization and nuclear translocation of fluorescein isothiocyanate-labeled hEGF were evaluated by confocal microscopy in MDA-MB-468 cells (1.3 x 10(6) EGFRs/cell) in the presence or absence of 1 microM gefitinib. The proportion of radioactivity partitioning into the cytoplasm and nucleus of MDA-MB-468 cells after incubation with (111)In-DTPA-hEGF for 24 h at 37 degrees C in the presence or absence of 1 microM gefitinib was measured by cell fractionation. DNA double-strand breaks caused by (111)In were quantified using the gamma-H2AX assay, and radiation-absorbed doses were estimated. Clonogenic survival assays were used to measure the cytotoxicity of (111)In-DTPA-hEGF alone or in combination with gefitinib. RESULTS: Gefitinib (1 microM) completely abolished EGFR phosphorylation in MDA-MB-468 cells. Internalization and nuclear translocation of fluorescein isothiocyanate-labeled EGF were not diminished in gefitinib-treated cells compared with controls. The proportion of internalized (111)In that localized in the nucleus was statistically significantly greater when (111)In-DTPA-hEGF was combined with gefitinib compared with (111)In-DTPA-hEGF alone (mean +/- SD: 26.0% +/- 5.5% vs. 14.6% +/- 4.0%, respectively; P < 0.05). Induction of gamma-H2AX foci was greater in MDA-MB-468 cells that were treated with (111)In-DTPA-hEGF (250 ng/mL, 1.5 MBq/mL) plus gefitinib (1 microM ) compared with those treated with (111)In-DTPA-hEGF alone (mean +/- SD: 35 +/- 4 vs. 24 +/- 5 foci per nucleus, respectively). In clonogenic assays, a significant reduction in the surviving fraction was observed when (111)In-DTPA-hEGF (5 ng/mL, 6 MBq/microg) was combined with gefitinib (1 microM ) compared with (111)In-DTPA-hEGF alone (42.9% +/- 5.7% vs. 22.9% +/- 3.6%, respectively; P < 0.01). CONCLUSION: The efficacy of (111)In-DTPA-hEGF depends on internalization and nuclear uptake of the radionuclide. Nuclear uptake, DNA damage, and cytotoxicity are enhanced when (111)In-DTPA-hEGF is combined with gefitinib. These results suggest a potential therapeutic role for peptide receptor radionuclide therapy in combination with tyrosine kinase inhibitors. 相似文献
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