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81.
Objective: To investigate the efficiency and potential mechanisms of exosomes from dendritic cells (DCs) transfected with Forkhead box protein P3 (FOXP3) in the development of experimental autoimmune encephalomyelitis (EAE).Method: Mouse bone marrow-derived immature DCs were loaded with adenovirus carrying FOXP3 gene, and exosomes were generated. Then the exosomes with FOXP3 (FOXP3-EXOs) were co-cultured with CD4+T cell in vitro to evaluate their potential on CD4+T cell proliferation and differentiation, and injected into EAE mice to assess their effects on the development of EAE.Result: FOXP3-EXOs were effective to inhibit the CD4+T cell proliferation and the production of Interferon gamma (IFN-γ), interleukin (IL)-6, and IL-17, while they promoted the production of IL-10 in vitro. Moreover, FOXP3-EXOs treatment significantly decreased the neurological scores, reduced the infiltration of inflammatory cells into the spinal cord, and decreased demyelination in comparison to saline and Con-EXOs treated EAE mice. Moreover, the FOXP3-EXOs treatment resulted in obvious increases in the levels of regulatory T (Treg) cells and IL-10, whereas levels of T helper 1 (Th1) cells, Th17 cells, IFN-γ, IL-6, and IL-17 decreased significantly in the splenocyte culture of EAE mice.Conclusion: The present study preliminarily investigated the effects and potential mechanisms of FOXP3-EXOs in EAE and revealed that the FOXP3-EXOs could inhibit the production of Th1 and Th17 cells and promote the production of Treg cells as well as ameliorate the development of EAE. The neuroprotective effects of FOXP3-EXOs on EAE are likely due to the regulation of Th/Treg balance.  相似文献   
82.
术后脑梗塞     
术后脑梗塞并非罕见,一旦发生患者的预后严重恶化,还易引起医患纠纷.但重要的是至今我们对此没有规范的防治方法.此文回答了常见的有关问题:术后脑梗塞的危险因素、发病率、发病机制、既往有脑血管病患者行择期手术的推荐做法和脑梗塞的早期治疗.  相似文献   
83.
目的 观察替吉奥单药治疗老年晚期乳腺癌的疗效与安全性。方法 回顾性分析老年晚期乳腺癌患者65例,研究组32例(S组):替吉奥 40~60 mg(<1.25 m2,40 mg; 1.25~1.5 m2,50 mg;>1.5 m2,60 mg),于早、晚饭后口服,连服14天,21天重复。对照组33例(X组):卡培他滨每日2000 mg/m2,分2次,连服14天,21天重复,至少2周期后评价疗效。结果 65例患者均可评价疗效, S组、X组有效率(RR)分别为31.3%(10/32)、27.3%(9/33),疾病控制率(DCR)分别为78.1%(25/32)、69.7%(23/33),中位疾病进展时间(TTP)分别为7.5、7.0月,中位总生存时间(OS)分别为17.3、15.2月,两组比较差异无统计学意义(P>0.05)。研究组与对照组常见的不良反应为骨髓抑制、胃肠道反应、口角炎、乏力,多见Ⅰ~Ⅱ度,可耐受,两组差异无统计学意义;对照组手足综合征明显高于研究组,差异有统计学意义(P=0.000)。 结论 替吉奥单药治疗老年乳腺癌疗效肯定,耐受性好于卡培他滨,值得临床进一步研究、推广。  相似文献   
84.
巨噬细胞是机体固有免疫反应的重要组成成份,在不同趋化因子的作用下极化为具有不同表面标志及功能的巨噬细胞。大量研究表明,肿瘤组织中的巨噬细胞为M2型,其能够促进肿瘤生长、侵袭和转移。M2型巨噬细胞在适当的诱导下可以转换为M1型。本文将近年来从HIV-1 Nef蛋白、CD40L、双磷酸盐及CpG-DNA联合IL-10R抗体等方面对巨噬细胞表型逆转的研究做一综述。巨噬细胞的表型逆转将可能为未来肿瘤治疗提供新的策略。  相似文献   
85.
OBJECTIVE: To assess the utilization rates of and complications associated with inpatient hysterectomy in California between 1991 and 2004. METHODS: We used the California Patient Discharge Database to analyze International Classification of Diseases, 9th Revision, Clinical Modification diagnostic and procedure codes for 649,758 women undergoing inpatient hysterectomy in California between 1991 and 2004 using multiple logistic regression models. RESULTS: Between 1991 and 2004, the incidence of any type of inpatient hysterectomy for benign gynecologic conditions declined 17.6%. The rates of laparoscopically assisted vaginal hysterectomy and subtotal hysterectomy increased substantially. The year of hysterectomy was a factor associated with both medical and surgical complications; the odds of inpatient complications between 1991 and 2004 steadily declined. CONCLUSION: In California between 1991 and 2004, the incidence of inpatient hysterectomy for benign gynecological conditions and the adjusted odds of complications declined substantially. Changes in practice and shorter hospital stays may have affected the changes in inpatient hysterectomy rates and associated inpatient complications.  相似文献   
86.
Jin X  Kang S  Wang N  Xing YP  Li Y 《中华妇产科杂志》2008,43(3):209-212
目的 探讨细胞周期调控基因p21和p27的单核苷酸多态性(SNP)与卵巢上皮性癌(卵巢癌)发病风险的关系.方法 采用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)方法检测234例卵巢癌患者(卵巢癌组)和284例健康妇女(对照组)p21基因C/T和p27基因V/G SNP位点基因型和等位基因的频率分布.结果 (1)对照组妇女p21基因的C/C、C/T和T/T基因型频率分别为34.2%、49.6%和16.2%,C和T等位基因频率分别为59.0%和41.0%;卵巢癌组患者3种基因型频率分别为28.2%、53.0%和18.8%,C和T等位基因频率分别为54.7%和45.3%.两组基因型频率和等位基因频率分别比较,差异均无统计学意义(P>0.05).3种基因型频率在4种病理类型的卵巢癌中的分布有明显差异(P=0.02),C/C基因型降低子宫内膜样癌的发病风险(OR为0.56,95%CI为0.32~0.98).(2)对照组妇女p27基因V/V、V/G和G/G基因型频率分别为88.4%、10.9%租0.7%,V和G等位基因频率分别为93.8%和6.2%;卵巢癌组患者的基因型频率分别为93.6%、5.1%和1.3%,V和G等位基因频率分别为96.2%和3.8%.两组基因型频率分布比较,差异有统计学意义(P=0.04),等位基因频率分布比较,差异则无统计学意义(P=0.09).与V/G和G/G基因型比较,V/V基因型增加卵巢癌的发病风险(OR为1.92,95%CI为1.02~3.63).结论 p21基因C/T多态性的C/C基因型可能降低子宫内膜样癌的发病风险,p27基因的V/V基因型可能是卵巢癌发病的潜在危险因素.  相似文献   
87.
BACKGROUND: The pre-eclampsia is characterized by placental defective angiogenesis and maternal vascular/endothelial dysfunction. Recently, the decrease and senescence of endothelial progenitor cells (EPC) has been observed in maternal circulation with pre-eclampsia. Given the essential involvement of EPC in neovascularization and reendothelialization, we investigate whether or not the depletion of EPC is existent in placental/fetal circulation with maternal pre-eclampsia. METHODS: Samples of venous cord blood were collected during the labor of preeclamptic mothers (n = 14) and normotensive controls (n = 10). Circulating EPC were enumerated as AC133+/KDR+ cells via fluorescence-activated cell sorting (FACS) analysis. Additionally, EPC were expanded in vitro and identified by DiI-acLDL uptake and lectin staining by direct fluorescent staining under a laser scanning confocal microscope. EPC proliferation, migration and vasculogenesis activities were determined by MTT, modified Boyden chamber assay and in vitro vasculogenensis assay. RESULT: The placental/fetal circulating EPC numbers were significantly decreased in the pre-eclampsia group compared with the control (median, 200; range, 100-440 cells/mL vs 390; 270-440 cells/mL, P < 0.001), and after in vitro cultivation the numbers of EPC also decreased in pre-eclampsia group (19.5; 5.0-32.0 vs 39.5; 31.2-52.0 EPC/x200 field; P < 0.001). Both circulating EPC and cultivated EPC were inversely correlated with cord blood level of soluble fms-like tyrosine kinase 1 (sFlt-1). In addition, the EPC from patients with pre-eclampsia were significantly impaired in their proliferation, migration and vasculogenesis capacities. CONCLUSION: The present study documented the decrease and dysfunction of placental/fetal circulating EPC in patients with pre-eclampsia. The alteration is probably associated with the increased sFlt-1 levels in the umbilical cord blood.  相似文献   
88.
89.
从食管癌高发区河南省林县的粮食中,分离出5株圆弧青霉(Penicillium cyclopiumWestling)用大米做培养基,25℃培养两周,经氯仿:甲醇等连续提取后,得到棕褐色膏状提取物。用其中的4株,诱发出了人羊膜FL细胞株的程序外DNA合成(Unscheduled DNA Synthesis,UDS)与DNA合成抑制(DNA Synthesis Inhibition,DSI),与溶剂对照比较,具有显著性差异(P<0.05),并在一定程度上存在剂量效应关系;加S_9后,其生物学活性明显降低,推测此提取物中含有能引起人羊膜细胞DNA损伤的直接诱变剂。  相似文献   
90.
The fabrication of fiber-reinforced metal matrix composites (MMCs) mainly consists of two stages: infiltration and solidification, which have a significant influence on the properties of MMCs. The present study is primarily focused on the simulation of the solidification process and the effect of the active cooling of fibers with and without nickel coating for making the continuous carbon fiber-reinforced aluminum matrix composites. The thermomechanical finite element model was established to investigate the effects of different cooling conditions on the temperature profile and thermal stress distributions based on the simplified physical model. The predicted results of the temperature distribution agree well with the results of the references. Additionally, a three-dimensional cellular automata (CA) finite element (FE) model is used to simulate the microstructure evolution of the solidification process by using ProCAST software. The results show that adding a nickel coating can make the heat flux smaller in the melt, which is favorable for preventing debonding at the coating/fiber and alloy interface and obtaining a finer microstructure. In the presence of the nickel coating, the number of grains increases significantly, and the average grain size decreases, which can improve the properties of the resultant composite materials. Meanwhile, the predicting results also show that the interfaces of fiber–coating, fiber–melt, and coating–melt experience higher temperature gradients and thermal stresses. These results will lead to the phenomenon of stress concentration and interface failure. Thus, it was demonstrated that these simulation methods could be helpful for studying the solidification of fiber-reinforced MMCs and reducing the number of trial-and-error experiments.  相似文献   
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