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11.
目的 探讨雷帕霉素(rapamycin)与顺铂(cisplatin)联合使用对趋化因子CCL19调节头颈鳞状细胞癌细胞活性的影响.方法 应用甲基噻唑基四唑(MTT)法及流式细胞仪检测顺铂及雷帕霉素对CCL19诱导后人头颈鳞状细胞癌淋巴结转移细胞系(PCI-4B、PCI-37B)生长抑制作用、细胞凋亡作用和细胞周期变化.使用Calcusyn软件计算两种药物(浓度比为80:1)联合使用时的剂量效应参数及联合指数(combination index,CI),使用SPSS 11.0软件包进行统计分析.结果 顺铂及雷帕霉素可以分别提高CCL19作用后细胞的生长抑制率(CCL19+顺铂作用后两细胞系的生长抑制率为21.22%±2.68%和22.76%±2.79%,CCL19+雷帕霉素作用后为19.46%±2.54%和20.6%±4.38%)、细胞G1期比例(CCL19+顺铂作用后两细胞系的G1期比例为72.14%±2.66%和76.39%±1.45%,CCL19+雷帕霉素作用后为75.26%±5.92%和74.00%±1.51%)和凋亡率(CCL19+顺铂作用后两细胞系的凋亡率9.59%±0.86%和7.55%±0.66%,CCL19+雷帕霉素作用后为8.21±1.80%和6.26±0.78%).两种药物浓度比为80:1联合使用时,PCI-4B细胞在半数抑制量(inhibitory concentration 50%,IC50)以下,CI<1,IC75以上CI>1;PCI-37B则在IC75以下CI<1,IC90以上CI>1.结论 顺铂及雷帕霉素均有抑制CCL19对人头颈鳞状细胞癌淋巴结转移细胞的活性调节作用,并且二者联合使用存在协同作用.Abstract: Objective To investigate the synergistic effects of rapamycin and cisplatin on head and neck squamous cancer cells regulated by chemokine( C-C motif) ligand 19 (CCL19). Methods The role of rapamycin and cisplatin was detected on cell-cycle and apoptosis in CCL19 induced PCI-4B and PCI-37B cells by methyl thiazolyl tetrazolium (MTT) and flow cytometry(FCM). Dose-effect relationship parameters and combination index(CI) were calculated on the median-effect equation and multiple drug effect equation using computer software CalcuSyn. Statistical analysis was performed by the unpaired student's t-test.Results Rapamycin and cisplatin could respectively increase the growth arrest, the proportion of G1 phase and apoptosis of CCL19 induced cancer cells (P <0. 05 ). Under inhibitory concentration 50% (IC50), CI was less than 1, and in IC75, it was more than 1 in PCI-4B cells. In PCI-37B cells, under IC75, CI was less than 1, and in IC90, it was more than 1. Conclusions Rapamycin and cisplatin can inhibit CCL19-regulated PCI-4B and PCI-37B cells' survival. The two drugs have synergistic effects when used in combination. 相似文献
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Tumor-infiltrating lymphocyte (TIL) in the primary site of oral SCC treated with S-PVP of PVP therapy was collected respectively and its yield,that is calculating the amount of TIL per tumor tissue.The cytotoxicity of TIL against the target,Tca8113 was detected.The results showed that the yield of TIL in S-PVP group was three times over that in PVP group.At the ratio of 5 to 1 (effector to target) the cytotoxicity was 38% in S-PVP group and 32% in PVP group.There was no significant difference in its cytotoxicity between two groups.The results revealed that immunochemotherapy of S-PVP regimen for treating oral SCC had neither direct damage to tumor cell from the agents nor antitumor immune reactivity with BRM stimulating an increasing in numbers of TIL. 相似文献
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髁突形态与骨性Ⅲ类不同垂直骨面型患者生长发育的相关性 总被引:4,自引:1,他引:4
目的:探讨髁突形态与骨性Ⅲ类不同垂直骨面型患者生长发育的关系。方法:采用计算机辅助X线头影测量技术,对不同年龄组骨性Ⅲ类不同垂直骨面型患者的全口曲面断层片进行测量,比较各组间髁突形态特点。结果:高角患者中:升支高度(RH)值在不同年龄段均有显著性差异(P<0.001),成人组>青少年组>儿童组(P<0.05);髁突上部高度(h)值、h/RH值、H/W值在不同年龄组中有显著性差异(P<0.05),且成人组分别大于青少年组和儿童组。均角患者中:h值、RH值均有显著性差异(P<0.001),且成人组分别大于青少年组和儿童组;h/RH值、H/W值在各年龄段间无统计学差异(P>0.05)。低角患者中:h值、RH值在各组中均有显著性差异(P<0.001),且成人组分别大于青少年组和儿童组;h/RH值在各年龄段间无统计学差异(P>0.05);H/W值在不同年龄组间有显著性差异(P<0.01),且儿童组和成人组分别大于青少年组。结论:髁突形态在骨性Ⅲ类不同垂直骨面型患者生长发育过程中存在差异,这可能与他们不同的生长型有关。 相似文献
15.
As orthodontic appliances can corrode with time in the oral environment, the aim of this study was to compare the release of metal ions from new and recycled brackets immersed in buffers of different pH values over a 48 week period. To simulate commercial recycling, the stainless steel brackets were divided into two groups: new and recycled. The bases of the latter were coated with adhesive and the brackets were heat treated before being immersed in the test solution for 48 weeks. The release of nickel, chromium, iron, copper, cobalt and manganese ions was analysed by atomic absorption spectrophotometry. Differences were compared using one-way analysis of variance. The results showed that recycled brackets released more ions than new brackets (P < 0.05). Brackets immersed in solutions of pH 4 released more ions than those immersed in solutions of pH 7, and the total amount of ions released increased with time over the 48 week period (P < 0.05). This study demonstrates that both new and recycled brackets will corrode in the oral environment. To avoid clinical side-effects, metal brackets should be made more resistant to corrosion, and recycled brackets should not be used. 相似文献
16.
丁荣晶 《中华全科医师杂志》2021,(2)
我国心血管疾病人群有3.3亿人,农村地区不仅患病率仍呈上升趋势,死亡率也高于城市,提示我国亟须加强心血管疾病的预防和康复治疗,而且重点在基层农村地区。心脏康复是目前指南推荐的心血管疾病慢性期最佳的治疗方案,基层医院应是心血管疾病预防和康复治疗的主要场所,是心血管疾病管理成败的关键环节。制定适合基层医院使用的心脏康复指南,将有利于心脏康复在基层的推广普及,《冠心病心脏康复基层指南(2020年)》正是在这一背景下应运而生。本文对指南的特点进行介绍,并阐述在基层推广心脏康复存在的障碍和策略。 相似文献
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Daofang Ding Leqin Xu Hao Xu Xiaofeng Li Qianqian Liang Yongjian Zhao Yongjun Wang 《中国神经再生研究》2014,9(1):25-32
To date, it remains poorly understood whether astrocytes can be easily reprogrammed into neurons. Mashl and Brn2 have been previously shown to cooperate to reprogram fibroblasts into neurons. In this study, we examined astrocytes from 2-month-old Sprague-Dawley rats, and found that Brn2 was expressed, but Mashl was not detectable. Thus, we hypothesized that Mashl alone could be used to reprogram astrocytes into neurons. We transfected a recombinant MSCV-MASH1 plasmid into astrocytes for 72 hours, and saw that all cells expressed Mashl. One week later, we observed the changes in morphology of astrocytes, which showed typical neuro- nal characteristics. Moreover, β-tubulin expression levels were significantly higher in astrocytes expressing Mashl than in control cells. These results indicate that Mashl alone can reprogram astrocytes into neurons. 相似文献
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