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991.
血管紧张素Ⅱ通过核因子κB上调巨噬细胞基质金属蛋白酶诱导因子的表达 总被引:1,自引:1,他引:1
目的 观察血管紧张素Ⅱ对巨噬细胞表达基质金属蛋白酶诱导因子的影响及其相关通路.方法 血管紧张素Ⅱ体外刺激人巨噬细胞,应用逆转录聚合酶链反应和Western blot测定基质金属蛋白酶诱导因子基因和蛋白表达;RNA干扰技术沉默核转录因子核因子κB p65亚基,评价核因子κB通路在血管紧张素Ⅱ上调巨噬细胞细胞基质金属蛋白酶诱导因子的表达中的作用.结果 血管紧张素Ⅱ刺激巨噬细胞后,基质金属蛋白酶诱导因子mRNA和蛋白表达均显著增加,核因子κB p65亚基沉默后,血管紧张素Ⅱ对基质金属蛋白酶诱导因子mRNA和蛋白表达无上调作用.结论 血管紧张素Ⅱ上调基质金属蛋白酶诱导因子的表达,此调控过程有核因子κB通路的参与. 相似文献
992.
重组人促红细胞生成素治疗结肠和直肠癌化疗相关贫血 总被引:4,自引:1,他引:4
目的 :观察重组人促红细胞生成素 (rhEPO)治疗结、直肠癌化疗相关贫血的疗效。方法 :选择 6 2例结、直肠癌采用以奥沙利铂为主联合方案化疗所致贫血患者 ,随机分为两组 :rhEPO治疗组 34例 ,给予皮下注射rhEPO 4 0 0 0 0U/周。对照组 2 8例 ,不给予rhEPO治疗 ,仅给予五参芪口服液。结果 :治疗后 4周起治疗组患者血红蛋白 (Hb) ,红细胞压积 (HCT)、红细胞总数 (RBC)均明显上升 ,与对照组相比差异有统计学意义 (P <0 .0 1)。rhEPO治疗组总有效率为 79.4 % ,对照组为 2 1.7% ,差异有统计学意义 (P <0 .0 1)。结论 :rhEPO 4 0 0 0 0U/周对晚期结、直肠癌联合方案化疗相关贫血有肯定的疗效 相似文献
993.
994.
Optical properties of human normal small intestine tissue determined by Kubelka-Munk method in vitro 总被引:2,自引:0,他引:2
AIM: To study the optical properties of human normal small intestine tissue at 476.5 nm, 488 nm, 496.5 nm, 514.5 nm, 532 nm, 808 nm wavelengths of laser irradiation. METHODS: A double-integrating-sphere system, the basic principle of measuring technology of light radiation, and an optical model of biological tissues were used in the study. RESULTS: The results of measurement showed that there were no significant differences in the absorption coefficients of human normal small intestine tissue at 476.5 nm, 488 nm, 496.5 nm laser in the Kubelka-Munk two-flux model (P>0.05). The absorption coefficients of the tissue at 514.5 nm, 532 nm, 808 nm laser irradiation were obviously increased with the decrease of these wavelengths. The scattering coefficients of the tissue at 476.5 nm, 488 nm, 496.5 nm laser irradiation were increased with the decrease of these wavelengths. The scattering coefficients at 496.5 nm, 514.5 nm, 532 nm laser irradiation were obviously increased with the increase of these wavelengths. The scattering coefficient of the tissue at 532 nm laser irradiation was bigger than that at 808 nm. There were no significant differences in the total attenuation coefficient of the tissue at 476.5 nm and 488 nm laser irradiation (P>0.05). The total attenuation coefficient of the tissue at 488 nm, 496.5 nm, 514.5 nm, 532 nm, 808 nm laser irradiation was obviously increased with the decrease of these wavelengths, and their effective attenuation coefficient revealed the same trend. There were no significant differences among the forward scattered photon fluxe, backward scattered photon fluxe, and total scattered photon fluxe of the tissue at 476.5 nm, 488 nm, 496.5 nm laser irradiation. They were all obviously increased with attenuation of tissue thickness. The attenuations of forward and backward scattered photon fluxes, and the total scattered photon fluxe of the tissue at 514.5 nm laser irradiation were slower than those at 476.5 nm, 488 nm, 496.5 nm laser irradiation respectively. The attenuations of forward and backward scattered photon fluxes, and total scattered photon fluxes at 532 nm laser irradiation were obviously slower than those at 476.5 nm, 488 nm, 496.5 nm, 514.5 nm laser irradiation. The attenuations of forward and backward scattered photon fluxes, and total scattered photon fluxe at 808 nm laser irradiation were all obviously slower than those at 476.5 nm, 488 nm, 496.5 nm, 514.5 nm, 532 nm laser irradiation respectively. CONCLUSION: There are significant differences in optical parameters of human normal small intestine tissue in the Kubelka-Munk two-flux model at six different wavelengths of laser radiation. The results would provide a new method of information analysis for clinical diagnosis. 相似文献
995.
C反应蛋白与动脉粥样硬化性心脑血管病 总被引:2,自引:0,他引:2
在动脉粥样硬化形成的炎症机制中 ,C反应蛋白 (CRP)起着重要作用。超敏CRP检测可用于评价动脉粥样硬化性心脑血管病的危险性。通过监测CRP指导抗炎治疗 ,可能会在心脑血管病的一、二级预防中发挥重要作用。 相似文献
996.
目的 从新疆株细粒棘球蚴中克隆细胞外信号调节激酶(EgERK1)基因,进行序列测定、生物信息学分析,蛋白表达及功能初步鉴定.方法 设计特异性引物,从新疆株细粒棘球蚴中提取总RNA,RT-PCR法扩增EgERK1基因,构建pET28a-EgERK1原核表达质粒,测序确定序列并进行生物信息学分析.构建正确的pET28a-EgERK1原核表达质粒,经诱导、表达EgERK1重组蛋白,聚丙烯酰胺凝胶电泳和Western印迹检测其生物学功能.结果 RT-PCR扩增出的条带经测序,结果显示其长度为1125 bp,编码374个氨基酸,等电点为6.34,BLAST比对结果提示为一薪基因,命名为EgERK1(EU701008).同源性比较表明,EgERK1与多房棘球绦虫ERK基因(EmMPK1)同源性为95.45%,与线虫、酵母、果蝇和人类等ERK基因的同源性为43.04%~61.88%.进化树分析发现EgERK1和EmMPK1相聚集.功能分析预测EgERK1具有ERK类激酶T-X-Y结构保守区和酶激活功能域.Western印迹显示,原核诱导表达的EgERK1重组蛋白能与抗人ERK1/2抗体发生特异性免疫反应.结论 成功克隆细粒棘球蚴EgERK1新基因,发现EgERK1重组蛋白具有与ERK1/2抗体结合的功能,为进一步研究该基因在寄生虫与宿主相互作用中的功能奠定基础. 相似文献
997.
无创动脉硬化检测最新进展 总被引:2,自引:0,他引:2
在心血管疾病中,动脉硬化是连接心血管危险因素和心血管事件的桥梁,及时识别判断动脉硬化程度已成为预防事件的重点。脉搏波传导速度作为重要的检测手段已被广泛接受,在通过监测血压来判断动脉硬化程度的研究中,动态动脉硬化指数逐渐被国内外研究人员所认可,不仅证实了其与高血压靶器官损害的相关性,其对事件的预测价值也得到肯定,而作为动态动脉硬化指数的改进指标的对称性动态动脉硬化指数消除了杓形曲线对指标的影响,有更广阔的临床科研应用前景。 相似文献
998.
国产封堵器治疗先天性膜周部室间隔缺损的疗效评估 总被引:2,自引:0,他引:2
目的 评价应用国产封堵器治疗先天性膜周部室间隔缺损(pmVSD)的近期疗效和安全性.方法 选择2001年12月至2008年12月在上海长海医院心内科使用国产封堵器治疗的pmVSD患者604例.所有患者术后1周每天观察临床症状并行12导联心电图检查,术后3~7 d复查经胸超声心动图(TTE)和X线胸片.结果 604例患者中封堵成功576例,共置入封堵器583枚,放弃封堵28例,手术成功率95.4%.无感染性心内膜炎、血栓栓塞、猝死等并发症发生.81例患者术后出现不同类型的传导阻滞,其中右束支传导阻滞56例,左束支传导阻滞14例.31例患者在术后出现一过性的加速性室性自主心律.完全性房室传导阻滞(cAVB)11例,9例在3周内恢复,2例安置永久性心脏起搏器,其中1例术前有一过性cAVB,另1例为同时封堵房间隔缺损并室间隔缺损的患者.术后即刻,69例(12.0%)有微量-少量残余分流,术后7 d,31例分流完全消失,仍有38例(6.6%)存在微量-少量残余分流.术后主动脉瓣反流加重5例,2例由术前的微量加重到术后少量反流,3例由少量加重到中量;术后出现三尖瓣微-少量反流32例,中量反流3例.5例机械性溶血,其中1例持续5 d无好转,经导管取出封堵器,其余4例均在术后3~14 d恢复正常.1例术后出现股动脉假性动脉瘤,经加压包扎后消失.封堵器脱落1例,经导管取出,并成功行封堵治疗.封堵器移位1例,在原位置入另一封堵器.结论 使用国产封堵器治疗室间隔缺损成功率高,并发症少,是一种安全有效的治疗方法. 相似文献
999.
Xing J Jia CR Wang Y Guo J Cai Y 《Journal of cancer research and clinical oncology》2012,138(7):1221-1229
Purpose
This study investigated the effect of shRNA targeting survivin on cultured ovarian cancer cells and on a murine ovarian cancer xenograft.Methods
An RNAi plasmid for survivin was transfected into SKOV3 cells, and the effect of shRNA targeting survivin on the expression of survivin was determined. Transmission electron microscopy (TEM), flow cytometry, and TUNEL staining were used to assess apoptosis. The MTT assay was used to measure cell growth and changes in cisplatin sensitivity. SKOV3 cells were injected into nude mice, and the effect of shRNA targeting the survivin gene on tumor growth was assessed.Results
SKOV3 cells transfected with an RNAi plasmid against survivin had increased apoptosis and slower growth. At the molecular level, these cells also had lower expression of survivin. Nude mice inoculated with SKOV3 cells developed cancers, and treatment with shRNA targeting survivin markedly inhibited the growth of these cancers with no obvious side effects.Conclusions
Our studies of SKOV3 cells and ovarian cancer xenografts in nude mice indicate that shRNA targeting survivin has potential for the treatment of ovarian cancer. 相似文献1000.
Tianchen Wei Xiaowei Zhu Xueni Hou Yijiang Li Aoqing Dong Xinying Jiang Yu Huang Xue Dong Xiangrong Wang Guoqiang Chen Tieling Xing 《RSC advances》2022,12(6):3602
Caffeic acid (CA), as a natural plant-derived polyphenol, has been widely used in surface coating technology in recent years due to its excellent properties. In this work, caffeic acid was introduced into the preparation of photonic band gap materials. By controlling the variables, a reasonable preparation method of polystyrene (PS) @polycaffeic (PCA)–Cu(ii) core–shell microspheres was achieved: 1 mmol L−1 cupric chloride anhydrous (CuCl2), 3 mmol L−1 sodium perborate tetrahydrate (NaBO3·4H2O), 2 mmol L−1 CA and 2 g L−1 polystyrene (PS) were reacted at 50 °C for 10 min to prepare PS@PCA–Cu(ii) core–shell microspheres through rapid oxidative polymerization of CA coated PS of different particle diameters. The amorphous photonic crystal structure was self-assembled through thermal assisted-gravity sedimentation, resulting in structural color nanomaterials with soft and uniform color, no angle dependence, stable mechanical fastness and excellent UV resistance.Caffeic acid (CA), as a natural plant-derived polyphenol, has been widely used in surface coating technology in recent years due to its excellent properties. 相似文献