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991.
《Journal of pharmaceutical sciences》2019,108(8):2661-2667
In order to evaluate the in vivo effect of inhaled formulations, it is a gold standard to create a lung metastasis model by intravenously injecting cancer cells into an animal. Because the cancer grows from the blood vessel side, there is a possibility of underestimating the effect of an inhaled formulation administered to the lung epithelium side. In addition, the metastasis model has disadvantages in terms of preparation time and expense. The present study aimed to establish a new method to evaluate the effect of an inhaled small interfering RNA (siRNA) formulation that is more correct, more rapid, and less expensive. We investigated whether siRNA can suppress gene expression of plasmid DNA (pDNA) by serial pulmonary administration of siRNA and pDNA powders prepared by spray-freeze-drying. We revealed that formulations of dry siRNA powder significantly suppressed gene expression of pDNA powder compared with a control group with no siRNA. Naked siRNA inhalation powder with no vector showed the suppression of gene expression equivalent to that of an siRNA-polyethyleneimine complex without damaging tissues. These results show that the present method is suitable for evaluating the gene-silencing effect of inhaled siRNA powders. 相似文献
992.
993.
高效液相色谱法测定桂枝中3种有效成分的含量 总被引:10,自引:1,他引:10
目的:建立HPLC法测定桂枝中桂皮醛、栓皮酸和邻甲氧基栓皮醛的含量。方法:采用ODS色谱柱(150mm×4.6mm,5μm),以甲醇-水-冰乙酸(45:55:0.05)为流动相,流速为0.8 mL·min~(-1),紫外检测波长为280 nm。结果:栓皮醛、桂皮酸和邻甲氧基桂皮醛的线性范围(n=5)分别为0.125~2μg(r=0.999 8),0.003 2~2 μg(r=0.999 9),0.012 5~0.2μg(r=0.999 7),平均回收率(n=9)分别为99.3%,102.8%,98.9%。提取方法为甲醇冷浸12h。结论:本方法简便、准确,可为评价不同产地的桂枝质量提供依据。 相似文献
994.
To determine the role of the phospholipase D (PLD) pathway in injury and survival of alveolar epithelial cells, A549 cells were exposed to H2O2 (500 μM) which resulted in time-dependent injury and bi-phasic increase of PLD activity at 5 min and at 3 h, respectively. n-Butanol (0.5%) inhibited PLD activation, attenuated cell injury at 5 min of H2O2 exposure, but enhanced injury at 3 h of exposure. This activation was inhibited by treatment with catalase (500 units/ml). Exogenous phosphatidic acid mimicked the effects of PLD activation, and diphenyliodonium (NADPH oxidase inhibitor) reversed the decline in cell viability induced by H2O2 exposure. Propranolol (phosphatidic acid phospholydrolase inhibitor) and quinacrine (phospholipase A2 inhibitor) had weak effects on H2O2-induced PLD activation but reversed H2O2-induced injury. We speculate that PLD activation at the initiation of H2O2 exposure predominantly results in NAPDH oxidase activation, which mediates A549 cell injury, but turns to mediating cell survival as the H2O2 attack continues, which might be mainly due to the accumulation of intracellular phosphatidic acid. 相似文献
995.
目的 探索工业色谱法纯化山银花中绿原酸的最优工艺参数。方法 以绿原酸的转移率为评价指标,以山银花水提液过大孔树脂后的20%乙醇洗脱液为原料液,采用单因素及响应面设计试验,对采用工业色谱纯化山银花中绿原酸工艺中的原料液浓缩程度、固定相类型、流动相乙醇浓度、乙醇流速、进样量等主要工艺参数进行优化,确定了最优工业色谱纯化山银花中绿原酸的工艺条件。结果 工业色谱纯化山银花中绿原酸的最优工艺条件:以60℃,-0.1 MPa为浓缩条件,将原料液浓缩至原体积的0.166 7(1/6),工业色谱UV检测波长为230 nm,以PIPO-02色谱填料为固定相,以18.54%乙醇作为流动相,流速为14.57 mL·min-1,进样量为13.15 mg。该工艺绿原酸的平均转移率为95.49%,RSD=1.91%,绿原酸产品纯度为97.45%,RSD=3.30%。结论 经过工艺优化与验证,创立了一条工业色谱纯化山银花中绿原酸工艺路线,该工艺制备的绿原酸产品纯度>97%,绿原酸转移率高,工艺简单、无毒,溶剂易于回收,适合于山银花中绿原酸纯化的工业化生产。 相似文献
996.
S-allylcysteine scavenges singlet oxygen and hypochlorous acid and protects LLC-PK(1) cells of potassium dichromate-induced toxicity. 总被引:1,自引:0,他引:1
Omar Noel Medina-Campos Diana Barrera Sabina Segoviano-Murillo Diana Rocha Perla D. Maldonado Nicandro Mendoza-Patiño José Pedraza-Chaverri 《Food and chemical toxicology》2007,45(10):2030-2039
It has been found that S-allylcysteine (SAC), a garlic-derived compound, has in vivo and in vitro antioxidant properties. In addition, it is known that SAC is able to scavenge different reactive oxygen or nitrogen species including superoxide anion (O(2)(-)), hydrogen peroxide (H(2)O(2)), hydroxyl radical (OH()), and peroxynitrite anion (ONOO(-)) although the IC(5O) values for each reactive species has not been calculated and the potential ability of SAC to scavenge singlet oxygen ((1)O(2)) and hypochlorous acid (HOCl) has not been explored. The purposes of this work was (a) to explore the potential ability of SAC to scavenge (1)O(2) and HOCl, (b) to further characterize the O(2)(-), H(2)O(2), OH(), and ONOO(-) scavenging ability of SAC by measuring the IC(50) values using in vitro assays, and (c) to explore the potential ability of SAC to ameliorate the potassium dichromate (K(2)Cr(2)O(7))-induced cytotoxicity in LLC-PK1 cells in which oxidative stress is involved. The scavenging activity was compared against the following reference compounds: N-acetylcysteine for O(2)(-), sodium pyruvate for H(2)O(2), dimethylthiourea for OH(), lipoic acid and glutathione for (1)O(2), lipoic acid for HOCl, and penicillamine for ONOO(-). It was found that SAC was able to scavenge concentration-dependently all the species assayed with the following IC(5O) (mean+/-SEM, mM): O(2)(-) (14.49+/-1.67), H(2)O(2) (68+/-1.92), OH() (0.68+/-0.06), (1)O(2) (1.93+/-0.27), HOCl (2.86+/-0.15), and ONOO(-) (0.80+/-0.05). When the ability of SAC to scavenge these species was compared to those of the reference compounds it was found that the efficacy of SAC (a) to scavenge O(2)(-), H(2)O(2), OH(), and ONOO(-) was lower, (b) to scavenge HOCl was similar, and (c) to scavenge (1)O(2) was higher. In addition, it was found that SAC was able to prevent K(2)Cr(2)O(7)-induced toxicity in LLC-PK1 cells in culture. It was showed for the first time that SAC is able to scavenge (1)O(2) and HOCl and to ameliorate the K(2)Cr(2)O(7)-induced toxicity. 相似文献
997.
前列腺疾病患者血清TPSA、FPSA和PAP的检测及其意义 总被引:2,自引:0,他引:2
为探讨总前列腺特异性抗原 (TPSA)、游离前列腺特异性抗原 (FPSA)、前列腺酸性磷酸酶 (PAP)的检测对前列腺疾病的诊断价值 ,采用双抗体夹心酶联免疫 (ELISA)法对 3 8例前列腺癌、85例前列腺良性疾病和 40例正常人血清中 TPSA、FPSA和PAP水平进行了检测。结果显示 ,前列腺癌患者血清中 TPSA、 FPSA和 PAP水平均显著高于前列腺良性疾病组和正常对照组 (P<0 .0 1) ,F/ T比值前列腺癌组明显低于前列腺良性疾病组和正常组 (P<0 .0 1) ,前列腺良性疾病组与正常组无明显差别。 相似文献
998.
目的对采用盐酸非索非那定与卡介菌多糖核酸联合的方法对患有慢性荨麻疹的患者进行治疗的临床效果进行比较分析。方法抽取76例在我院就诊的患者有慢性荨麻疹的临床确诊患者病例,将其随机分为A、B两组,平均每组38例。A组患者采用单独使用卡介菌多糖核酸的方法进行治疗;B组患者采用盐酸非索非那定与卡介菌多糖核酸联合的方法进行治疗。对两组患者的临床治疗效果、并发症和不良反应情况进行比较分析。结果 B组患者额的临床治疗效果与A组患者比较,其有效率明显高出很多,有显著的统计学差异(P<0.05);两组中有个别患者出现头痛、头晕、恶心等症状,但是未对正常治疗造成影响。结论采用盐酸非索非那定与卡介菌多糖核酸联合的方法对患有慢性荨麻疹的患者进行治疗的临床效果十分明显,不会出现特别严重的并发症和不良反应现象,可以作为今后临床对该类患者进行治疗的首选方法。 相似文献
999.
1000.
目的合成全反式维甲酸(ATRA)的前体药物,增强ATRA对急性早幼粒白血病(APL)细胞的分化诱导作用。方法以乙二醇、对苯二酚、乙醇胺及乙二胺等为连接物,通过酯键和酰胺键将分化诱导剂ATRA与组蛋白去乙酰酶(mAC)抑制剂正丁酸、丙戊酸连接起来,形成前体药物。结果合成了13个ATRA与正丁酸或丙戊酸相连接的前体药物,化合物的结构经^1H-NMR、MS和IR确证。结论考察部分化合物对急性早幼粒细胞白血病细胞株NB4的生长抑制作用和对急性早幼粒白血病(APL)细胞分化诱导作用,初步的药理实验结果表明,ATRA与丙戊酸通过酰胺键连接时,对NB4细胞分化诱导能力显著增加。 相似文献