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991.
目的:将许旺细胞与细胞外基质凝胶、聚乳酸-羟基乙酸共聚物纤维丝复合培养,观察许旺细胞的存活、黏附、三维生长和迁移等生物学行为。方法:实验于2005-02/2006-03在四川大学完成。①实验材料:3~6月龄SD大鼠40只。16~24周流产胎儿由四川大学华西二医院计划生育科提供,产妇及其家属均签署知情同意书,实验经医学伦理委员会批准。聚乳酸-羟基乙酸共聚物(中国科学院成都分院化学所提供);细胞外基质凝胶(Sigma)。②实验方法:将聚乳酸-羟基乙酸共聚物溶解,旋转抽丝法制成直径为20~40μm的聚乳酸-羟基乙酸共聚物纤维丝。无菌条件下取胎儿坐骨神经,去除神经外膜,胰酶消化 差速贴壁法去除成纤维细胞,达80%融合时行BrdU标记。③实验评估:将许旺细胞离心制成0.1~0.2mm3的微粒,接种在细胞外基质凝胶中,观察许旺细胞在凝胶中的存活、生长和移行。将许旺细胞制成1×1010L-1的30%细胞外基质凝胶后,分别滴加在经过胶原、细胞外基质凝胶预处理的聚乳酸-羟基乙酸共聚物纤维丝的一端,观察许旺细胞在纤维丝上的黏附、生长和迁移。将BrdU标记的许旺细胞复合细胞外基质凝胶后,置入聚乳酸纤维管用以修复大鼠坐骨神经缺损,术后3,6周取材,BrdU免疫组化染色观察许旺细胞的存活情况。结果:①许旺细胞在无血清状态下能在细胞外基质凝胶中存活,并分裂、增殖,相互移行形成类似Bungner带状的许旺细胞柱状结构。②许旺细胞能贴附在聚乳酸-羟基乙酸共聚物纤维丝上生长并沿纤维丝移行,形成多层排列的类似Bungner带状的许旺细胞柱,细胞外基质凝胶能显著增加贴附和移行细胞数量,而胶原作用不显著。③许旺细胞和细胞外基质凝胶复合移植,6周后BrdU阳性细胞数明显低于第3周(t=3.71,P<0.01),成活细胞能在细胞外基质凝胶中移行。结论:许旺细胞与细胞外基质凝胶、聚乳酸-羟基乙酸共聚物纤维丝等生物材料复合培养时,能存活、分裂、增殖,相互移行形成类似Bungner带状的细胞柱,并可贴附在纤维丝上生长迁移,该生物学行为对神经组织工程具有重要作用。  相似文献   
992.
目的:分析腰椎间盘突出症患者血清细胞因子的表达及其与疼痛的关系,深化对其病变的认识。方法:于2005-02/12选择中国中医科学院望京医院及骨伤科研究所门诊和住院的腰椎间盘突出症患者43例,为试验组。腰椎间盘突出症根据临床症状结合CT和/或MRI影像学检查确诊。同期选择成年健康体检者30例,为正常组。应用放免法测定血清中白细胞介素1β、白细胞介素6、肿瘤坏死因子α的含量,采用目测类比评分法测定患者疼痛程度。结果:纳入患者43例和健康体检者30例,均进入结果分析。①试验组血清白细胞介素1β、白细胞介素6、肿瘤坏死因子α含量高于正常组,差异有显著性意义[分别为(0.40±0.17),(0.19±0.06)μg/L;(131.78±32.06),(108.85±41.48)μg/L;(1.84±0.49),(1.14±0.40)μg/L,P<0.01]。②疼痛和白细胞介素6依存性不显著(P>0.05),疼痛和白细胞介素1β、肿瘤坏死因子α呈数值依存性(P<0.01)。结论:腰椎间盘突出症患者血清白细胞介素1β、白细胞介素6、肿瘤坏死因子α异常升高,白细胞介素1β、肿瘤坏死因子α是导致疼痛的重要因素。  相似文献   
993.
Offspring of childhood cancer survivors may be at risk of genetic disease due to the mutagenic cancer treatments received by their parents. Congenital malformations were evaluated in a population-based cohort study of 1715 offspring of 3963 childhood cancer survivors and 6009 offspring of 5657 survivors' siblings. The Danish Central Population Register, Cancer Registry and Hospital Register were used to identify study subjects and congenital malformations. Gonadal and uterine radiation doses were characterized based on standard radiation-treatment regimens. The prevalence of congenital malformations at birth in offspring of survivors (44 cases, 2.6%) was slightly higher but not statistically different from that of offspring of siblings (140 cases, 2.3%) [prevalence proportion ratio (PPR), 1.1; 95% confidence interval, 0.8–1.5] or of the general population (observed-to-expected ratio, 1.2; 0.9–1.6). Including malformations diagnosed later in life did not change the ratios appreciably. The risk for malformations was slightly higher in the offspring of irradiated parents than in that of non-irradiated parents (PPR 1.2 vs 1.0) but was unrelated to gonadal dose. This study provides evidence that cancer therapy of children does not increase the risk for malformations in their offspring. Continued monitoring of genetic risks among their offspring, however, is warranted.  相似文献   
994.
995.
建立大鼠骨髓源性树突状细胞体外扩增及纯化的方法   总被引:1,自引:1,他引:0  
目的:目前对树突状细胞的研究主要集中在人及小鼠系统,关于大鼠树突状细胞特性和功能的研究较少。体外扩增并纯化大鼠骨髓树突状细胞的方法,并对其进行形态学和免疫学鉴定。方法:实验于2004-06/2005-06在第四军医大学西京医院耳鼻喉科实验室完成。实验材料:8~12周龄雌性SD大鼠由第四军医大学实验动物中心提供,实验过程中对动物处置符合动物伦理学标准。实验方法:①参考Oliver方法,利用黏附法诱导分离SD大鼠骨髓细胞,获得高纯度的树突状细胞。采用扫描电镜和透射电镜观察培养6,8,10,12 d与12 d加内毒素情况下细胞形态,并采用流式细胞仪鉴定。②无菌条件下取出大鼠脾脏加RPMI1640培养液研磨并通过不锈钢筛网,收集未贴壁细胞,以RPMI1640培养液冲洗出的细胞作为反应细胞。取96孔培养板加入反应细胞,并按照1∶480,1∶240,1∶120,1∶60比例加入刺激细胞。采用ELX800型酶联免疫检测仪测定波长为490 nm处吸光度值。结果:①随培养时间的增长,细胞逐渐成熟,培养12 d的细胞形态不规则,表面有大量树突状突起,培养12 d加内毒素的细胞进一步成熟,体积增大,高表达CD80、CD86分子。②随着培养时间和树突状细胞数目的增加,树突状细胞刺激T细胞增殖的能力逐渐增强,加入内毒素后这种能力进一步加强。结论:成功地建立了体外大量扩增大鼠骨髓树突状细胞方法,并可在培养过程中收获不同成熟状态树突状细胞。  相似文献   
996.
Diclofenac is an important analgesic and anti-inflammatory drug, widely used for treatment of postoperative pain, rheumatoid arthritis, and chronic pain associated with cancer. Consequently, diclofenac is often used in combination regimens and undesirable drug-drug interactions may occur. Because many drug-drug interactions may occur at the level of drug transporting proteins, we studied interactions of diclofenac with apical ATP-binding cassette (ABC) multidrug efflux transporters. Using Madin-Darby canine kidney (MDCK)-II cells transfected with human P-glycoprotein (P-gp; MDR1/ABCB1), multidrug resistance protein 2 (MRP2/ABCC2), and breast cancer resistance protein (BCRP/ABCG2) and murine Bcrp1, we found that diclofenac was efficiently transported by murine Bcrp1 and moderately by human BCRP but not by P-gp or MRP2. Furthermore, in Sf9-BCRP membrane vesicles diclofenac inhibited transport of methotrexate in a concentration-dependent manner. We next used MDCK-II-MRP2 cells to study interactions of diclofenac with MRP2-mediated drug transport. Diclofenac stimulated paclitaxel, docetaxel, and saquinavir transport at only 50 microM. We further found that the uricosuric drug benzbromarone stimulated MRP2 at an even lower concentration, having maximal stimulatory activity at only 2 microM. Diclofenac and benzbromarone stimulated MRP2-mediated transport of amphipathic lipophilic drugs at 10- and 250-fold lower concentrations, respectively, than reported for other MRP2 stimulators. Because these concentrations are readily achieved in patients, adverse drug-drug interactions may occur, for example, during cancer therapy, in which drug concentrations are often critical and stimulation of elimination via MRP2 may result in suboptimal chemotherapeutic drug concentrations. Moreover, stimulation of MRP2 activity in tumors may lead to increased efflux of chemotherapeutic drugs and thereby drug resistance.  相似文献   
997.
INTRODUCTION: This meta-analysis was conducted to systematically review the efficacy and safety of the H-Wave(R) (Electronic Waveform Lab, Inc, Huntington Beach, CA, USA) device and programme as a non-pharmacological analgesic treatment in chronic soft tissue inflammation and neuropathic pain. METHODS: Five studies related to pain relief, reduction in pain medication and increased functionality obtained with the H-Wave device were included in the analysis. Data were analysed using the random effects model, including adjustment to evaluate variability, size of study and bias in effect size. A total of 6535 participants were included in the meta-analysis; there were 8065 participants' outcomes measured due to multiple measurements per participant. RESULTS: The H-Wave device decreased pain ratings across various chronic soft tissue inflammation and neuropathic pain conditions. The mean weighted effect size was 0.59, and the estimated effect size variance was 0.00003 (95% confidence intervals [CI]: 0.580, 0.600). The H-Wave device also decreased the intake of pain medication in patients with various chronic soft tissue inflammation and neuropathic pain conditions. The mean weighted effect size was 0.56, and the estimated effect size variance was 0.000013 (95% CI: 0.553, 0.567). Patient functionality was also improved with use of the H-Wave device. The mean weighted effect size was 0.70, and the estimated effect size variance was 0.00002 (95% CI: 0.691, 0.709). A chi-square test for homogeneous effect sizes found highly significant (P<0.00001) variability, indicating a robust significant effect size for increased functionality relative to both pain relief and reduction in pain medication. There was little to no evidence of any adverse effects associated with the use of the H-Wave device. CONCLUSION: The findings indicate a moderate to strong effect of the H-Wave device in providing pain relief, reducing the requirement for pain medication and increasing functionality. The most robust effect was observed for improved functionality, suggesting that the H-Wave device may facilitate a quicker return to work and other related daily activities.  相似文献   
998.

Introduction  

Breast cancer at a young age is associated with an unfavorable prognosis. Very young patients with breast cancer therefore are advised to undergo adjuvant chemotherapy irrespective of tumor stage or grade. However, chemotherapy alone may not be adequate in young patients with hormone receptor-positive breast cancer. Therefore, we studied the effect of adjuvant chemotherapy in young patients with breast cancer in relation to hormone receptor status.  相似文献   
999.
1000.
多沙唑嗪(DOX)存在一定心脏毒性作用,已非一线降压药物,但是作为治疗良性前列腺增生症合并下尿路症状(BPH/LUTS)的一线药物仍广泛应用于临床。同时,它可以轻度降低总胆固醇(TC)和甘油三脂(TG)水平。为减轻DOX心血管的不良反应,对其进行了手性拆分,发现DOX的分子中存在一个手性中心和一对光学异构体,即右旋多沙唑嗪((+)DOX)和左旋多沙唑嗪((-)DOX)。发现(-)DOX可能成为心血管不良反应较小的治疗BPH/LUTS药物。现就(±)DOX及其光学异构体对血脂代谢的作用的研究进展作一综述。  相似文献   
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