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991.
背景:目前关于氨基葡萄糖的研究多集中于对膝骨关节炎的治疗作用,但关于其对膝骨关节炎患者外周血中软骨代谢相关基因影响的研究有限。目的:观察氨基葡萄糖胶囊对膝骨关节炎的治疗效果及对软骨代谢相关基因表达的影响。方法:选取2017年3月至2019年2月郑州大学附属郑州中心医院收治的90例膝骨关节炎患者,另选取同期医院体检中心收入的40例健康受试者,检测并对比健康受试者与膝骨关节炎患者治疗前外周血单个核细胞中软骨寡聚基质蛋白、Ⅱ型胶原纤维α1、聚糖蛋白、特异性组织抑制物3基因表达水平。采用随机数表法将膝骨关节炎患者分为常规组和研究组,分别给予双氯芬酸钠缓释片、双氯芬酸钠缓释片+氨基葡萄糖胶囊治疗12周,对比治疗前后2组外周血单个核细胞中各基因表达水平、Lequesne指数,统计治疗期间2组不良反应发生情况。结果与结论:①与健康受试者比较,膝骨关节炎患者外周血单个核细胞中软骨寡聚基质蛋白、特异性组织抑制物3 mRNA相对表达量升高(P<0.05),Ⅱ型胶原纤维α1、聚糖蛋白mRNA相对表达量降低(P<0.05);②治疗前研究组和常规组外周血单个核细胞中各基因表达水平比较,差异均无显著性意义(P>0.05);治疗后2组外周血单个核细胞中软骨寡聚基质蛋白、特异性组织抑制物3 mRNA相对表达量均低于治疗前,且研究组低于常规组(P<0.05);治疗后2组外周血单个核细胞中Ⅱ型胶原纤维α1、聚糖蛋白mRNA相对表达量均高于治疗前,且研究组高于常规组(P<0.05);③治疗前研究组和常规组Lequesne指数比较,差异均无显著性意义(P>0.05);治疗后2组Lequesne指数均低于治疗前,且研究组低于常规组(P<0.05);④研究组和常规组不良反应发生率比较,差异均无显著性意义(P>0.05);⑤结果表明,氨基葡萄糖胶囊可有效改善膝骨关节炎患者临床症状且安全可靠,可能通过抑制软骨寡聚基质蛋白、特异性组织抑制物3基因表达,促进Ⅱ型胶原纤维α1、聚糖蛋白基因表达实现的。  相似文献   
992.
大脑中动脉血流变化对估计脐带绕颈胎儿预后的价值   总被引:1,自引:0,他引:1  
目的探讨大脑中动脉血流变化对估计脐带绕颈胎儿预后的价值。方法选取2006年1月~2006年9月足月妊娠妇女51例。其中观察组39例,均为脐带绕颈一周并经阴道分娩。结合胎儿预后将观察组分为胎窘组(15例)和正常组(24例)。对照组12例,为随机选择的同期正常妊娠并顺产的妇女。应用彩色多普勒超声技术对全部孕妇于临产前和活跃早期检测胎儿大脑中动脉阻力指标-收缩期峰值流速/舒张末期流速(S/D)、阻力指数(RI)和搏动指数(PI)。结果(1)临产前,胎窘组胎儿大脑中动脉血流S/D、RI、PI值较对照组和正常组皆显著升高(P<0.05);而对照组和正常组比较,差异不显著(P>0.05)。(2)活跃早期胎窘组胎儿大脑中动脉血流S/D、RI、PI值较对照组和正常组皆显著降低(P<0.05);而对照组和正常组比较,差异不显著(P>0.05)。结论大脑中动脉血流阻力指标的变化与脐带绕颈胎儿不良预后密切相关;临产前监测脐绕颈胎儿MCA血流阻力指标的变化可以作为早期评估胎儿预后的理想方法。  相似文献   
993.
c-Met, the receptor of hepatocyte growth factor is known to be responsible for the motility and mitogenesis of epithelial cells including cancer cells. To investigate the significance of c-Met expression in human colorectal cancer (CRC), total cellular protein, extracted from 130 CRCs were examined by Western blot analysis. The signal was quantitated by ChemiImager™ 4000 Low Light Imaging System. c-Met expression was analyzed as the ratio of tumor to matched normal tissue (T/N) and expressed as fold-increase. The cellular localization of c-Met was assessed by immunohistochemistry. The T/N fold increase of c-Met varied from 0.2 to 10.7 with a mean of 3.41 ± 0.23 (mean ± SE). 69% primary CRC showed overexpression (T/N >2.0) of c-Met. Significantly higher c-Met levels were found in CRC with blood vessel invasion (P = 0.04), and in advanced stage (P = 0.04). No relationship was noted between c-Met expression and age, tumor size, location, differentiation. C-Met immunoreactivity was observed in the membrane and cytoplasm of cancer cells. Positive staining of endothelial cells of blood vessels within normal submucosa and tumor was also evident. C-Met protein is expressed at levels significantly higher than adjacent mucosa in most primary adenocarcinomas of the colon. Our results support an important role for c-Met in human CRC progression and metastasis.  相似文献   
994.
BACKGROUND: Impaired implantation in assisted reproduction cycles with high serum estradiol (E(2)) concentrations may be related to suboptimal endometrial perfusion. Endometrial and subendometrial blood flow were compared between excessive responders (serum E(2) on the day of HCG >20 000 pmol/l) and moderate responders (E(2) < or =20 000 pmol/l). METHODS: Three-dimensional (3D) ultrasound examination with power Doppler was performed 2, 4 and 7 days after HCG in 32 patients who did not have embryo transfer in order to measure endometrial thickness, pulsatility index (PI)/resistance index (RI) of uterine vessels, and endometrial volume, vascularization index (VI)/flow index (FI)/vascularization flow index (VFI) of endometrial and subendometrial regions. RESULTS: Excessive responders tended to have lower endometrial and subendometrial VI/VFI on HCG +2 and more absent endometrial/subendometrial blood flow. They had significantly higher endometrial FI and subendometrial VFI than moderate responders on HCG +7. Only in the excessive responder group, uterine PI/RI declined significantly from HCG +2 to HCG +7 and endometrial VI/VFI increased significantly from HCG +4 to HCG +7. CONCLUSION: Changes in uterine Doppler flow indices, and endometrial and subendometrial 3D power Doppler flow indices during the early luteal phase were significantly different between moderate and excessive responders.  相似文献   
995.
从脐带血单核细胞来源树突状细胞(DC)表型变化的角度来探讨EB病毒对DC表型的影响,以阐明其逃逸宿主免疫的机制。将GM-CSF和IL-4、EB病毒和LPS不同组合对单核细胞来源DC进行刺激培养,利用单染色和三染色免疫荧光抗体标记—流式细胞术检测单核细胞来源DC表面CD14、CD11c、CD1a、HLA-DR、CD86、MR和MHCⅠ类分子。加入EB病毒后,DC表面CD14分子表达的下调不明显,CD1a的表达则随病毒加入时细胞的分化阶段有关;同时EB病毒还影响了加入LPS后HLA-DR和CD86的升高和MR的降低;EB病毒还影响了细胞表面MHCⅠ类分子的表达。因此EB病毒可抑制单核细胞来源DC的分化和成熟,这可能是其逃逸宿主免疫的机制之一。  相似文献   
996.
Blood flow in the large systemic arteries is modeled using one-dimensional equations derived from the axisymmetric Navier–Stokes equations for flow in compliant and tapering vessels. The arterial tree is truncated after the first few generations of large arteries with the remaining small arteries and arterioles providing outflow boundary conditions for the large arteries. By modeling the small arteries and arterioles as a structured tree, a semi-analytical approach based on a linearized version of the governing equations can be used to derive an expression for the root impedance of the structured tree in the frequency domain. In the time domain, this provides the proper outflow boundary condition. The structured tree is a binary asymmetric tree in which the radii of the daughter vessels are scaled linearly with the radius of the parent vessel. Blood flow and pressure in the large vessels are computed as functions of time and axial distance within each of the arteries. Comparison between the simulations and magnetic resonance measurements in the ascending aorta and nine peripheral locations in one individual shows excellent agreement between the two. © 2000 Biomedical Engineering Society. PAC00: 8719Uv  相似文献   
997.
A simple method is described for labelling cells with fluorescein and using them in artificial mixtures to assess cell separation procedures. The method facilitates the examination of the variables in a separation procedure. It is thus possible to tailor a separation procedure (for example panning with monoclonal antibody) to suit the specific requirements of the experiment.  相似文献   
998.
The role of β-adrenoceptors in exercise-induced muscle hyperaemia was investigated. Exercise was performed with a small and a large muscle mass: knee extension (KE) and bicycle exercise (BE). Seven healthy subjects performed light and maximal KE and eight subjects performed stepwise dynamic BE to exhaustion before and after acute i.v. administration of propranolol (0.15 mg kg-1). Leg blood flow was measured by a bolus dye dilution technique. During KE at low and high power leg blood flow was reduced by 8.7 and 10.5% after propranolol was administered, mean arterial blood pressure (MAP) was reduced at low, but not at high power resulting in increased leg vascular resistance (LVR) during high intensity. During BE propranolol reduced leg blood flow and increased LVR at low power, but not at high power. At high BE intensity LVR did not change with increasing power and was slightly decreased after propranolol was administered. In this situation oxygen uptake was close to maximum and the concentration of catecholamines was 3–5 times higher compared with KE. There was no significant effect of propranolol on lactate release or arterial-femoral venous (a-fv) differences for adrenaline or noradrenaline. We conclude that β-adrenoceptors modulate local vasodilation in skeletal muscles during exercise independently of local muscle energy demand, but that the effect is highly dependent on active muscle mass since a-adrenergic activity during maximal BE seemed to disguise any effect of propranolol on LVR.  相似文献   
999.
The effect of administration of cyclosporin A (CyA) or the novel macrolide FK506 was investigated in AO rats given DA blood transfusions. CyA (10 mg/kg, orally) or FK506 (1 mg/kg, intramuscularly) administered for 14 days from the time of transfusion effectively inhibited primary anti-MHC class I alloantibody production. This profound inhibitory effect persisted throughout the 2-month investigation period, with little increase in 'secondary' alloantibody production following a challenge injection 28 days after drug withdrawal. Flow cytometric analysis revealed no significant differences in the absolute numbers of W3/25+ (CD4+), OX-8+ (CD8+) or OX-12+ (B lymphocytes), in either the spleen or peripheral blood of transfused compared with normal, untreated animals. However, a small but significant increase in the numbers of splenocytes expressing the activation marker OX-40 (activated CD4+ cells) was observed in transfused animals. Either CyA or FK506 significantly reduced the number of cells expressing OX-39 (interleukin-2 receptors) and OX-40. Treatment of transfused animals with CyA, but not FK506 for 14 days resulted in minor, transient reduction in peripheral blood OX-19+ and W3/25+ cells, while 'sparing' the OX-8+ cells; these changes were not observed in spleens. In contrast, the absolute spleen cell numbers of OX-19+, W3/25+ and OX-8+ cells were significantly reduced in transfused animals given 14 days of FK506 treatment, while the corresponding blood cells were unaffected. Induction of splenic lymphoproliferative responses by the T cell mitogen concanavalin A remained normal in animals receiving transfusion alone or with CyA. In contrast, profound inhibition of mitogenic responses was observed in FK506-treated animals and this inhibitory effect declined gradually following drug withdrawal. No non-specific suppressor cell activity was detected in the spleens of rats given transfusion alone or in CyA or FK506-treated transfused animals.  相似文献   
1000.
A number of anti-H-2 alloantisera containing antibody reactive with I region gene products (Ia) of the major histocompatibility complex cross-react with determinants expressed by human peripheral blood B lymphocytes. Such data have led to the conclusion that Ia and DR antigens share cross-reacting determinants. We have attempted to generate mouse primed T lymphocyte populations specific for defined I region gene product determinants which concomitantly recognize DR determinants on human peripheral blood leukocytes in primed lymphocyte typing (PLT) analysis. Mouse PLT cells were generated in primary MLC using strain combinations identical to those in which positive mouse/human cross-reacting antisera have been obtained. The resulting PLT cells exhibited strong, yet specific, secondary MLC responses against mouse cells expressing the Ia determinants used as the primary stimulus. In contrast, when examined on panels of human peripheral blood leukocytes, no reactivity was detected. This lack of cross-reactivity suggests that mouse T cells primed toward Ia determinants do not regularly recognize cross-reacting determinants of DR or D-associated antigens expressed on human PBLs. Consequently, mPLT cells are not a useful reagent in defining HLA-D region polymorphism.  相似文献   
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