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51.
本实验采用环磷酰胺(CY)制造免疫功能低下小鼠的动物模型,研究当归补血汤组成药物的不同比例配伍,对机体免疫功能调节作用的影响。实验过程中将当归、黄芪分别配制成1∶1(A方)、1∶5(B方)、5∶1(C方)的不同比例中药方剂,对小鼠施以灌胃,并设对照组,以WBC总数、T淋巴细胞转化率及胸腺细胞超微结构变化作为检测指标。结果表明:三组不同比例配伍的方剂,对小鼠机体免疫功能均有调节作用。三组之间比较,提高WBC总数以A方效果最明显;三个方剂均有促进淋巴细胞转化的作用,但转化率三者之间无明显差异;保护胸腺细胞作用以B方效果最好。应用:当归补血汤对机体免疫功能有明显调节作用,但不同比例配伍,对机体免疫功能调节作用各有所侧重 相似文献
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53.
Since our major hypothesis is that prenatal protein malnutrition significantly affects hippocampal neuroplasticity, this study examined the effects of prenatal protein malnutrition on the modulation of dentate granule cell excitability in freely moving rats at 15, 30 and 90 days of age across the vigilance states of quiet waking (QW), slow-wave sleep (SWS) and rapid eye movement (REM) sleep. Using paired-pulse stimulation, the paired-pulse index (PPI), a measure of the type and degree of modulation of dentate granule cell excitability elicited by stimulation of the medial perforant path, was obtained for each vigilance state at each stage of development. Four specific measures of granule cell excitability were computed, namely, PPI using both population spike amplitude (PSA) and EPSP slope measures, absolute values of PSA(1) and EPSP(1) slope. PPI values obtained at 15, 30 and 90 days of age, however, were altered during normal ontogenetic development, but not by vigilance state. At 15 days of age, the malnourished group exhibits greater early inhibition of the PPI using the PSA measure at IPIs between 20 and 30 ms regardless of vigilance state, while at 30 days of age, the malnourished group exhibits greater facilitation at IPIs between 50 and 70 ms during QW and SWS, but not during REM sleep. In the control adult (PND90) and juvenile (PND30) animal, PSA(1) values are significantly higher during SWS than in QW or REM sleep. However, for the younger malnourished animals (PND15 and PND30), PSA(1) values were found to be significantly greater during REM sleep rather than SWS. Therefore, as the animal matures, there appears to be a shift in vigilance state dependent synaptic transmission through the hippocampal trisynaptic circuit from REM sleep to SWS in both control and malnourished animals, with the change occurring later in malnourished animals when compared to control ones. Furthermore, our findings suggests that prenatal protein malnutrition significantly alters modulation of dentate granule cell excitability (i.e., PPI values using the PSA measure) during the earlier stages of development but not in adulthood. 相似文献
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55.
Blockade of the NMDA receptor increases developmental apoptotic elimination of granule neurons and activates caspases in the rat cerebellum 总被引:2,自引:0,他引:2
Elimination of neurons produced in excess naturally occurs during brain development through programmed cell death. Among the many survival factors affecting this process, a role for neurotransmitters acting on specific receptors has been suggested. We have performed an in vivo pharmacological blockade of the N-methyl-D-aspartate (NMDA) subtype of glutamate receptors, using the competitive NMDA receptor antagonist CGP 39551 at developmental stages corresponding to those at which a survival dependence on the stimulation of this receptor has been demonstrated for cerebellar granule neurons explanted in culture (typically from postnatal day 7 to postnatal day 11 or 13). We were able to demonstrate an increased level of DNA fragmentation in the cerebellum of the treated rats. At the P11 stage, in particular, the fragmented DNA extracted from the cerebellum of CGP 39551-treated pups showed a clear laddering of nucleosomal fragments after agarose-gel electrophoresis. Accordingly, in situ TUNEL technique showed a remarkable increase of cells positive for nucleosomal DNA fragmentation, particularly in the inner granular layer of the cerebellum of treated rats at P11 stage. Therefore, the natural rate of apoptotic elimination of cerebellar granule neurons is considerably enhanced under conditions of pharmacological blockade of the NMDA receptor, thus demonstrating, for the first time in vivo, a clear survival dependence of these neurons upon the stimulation of the NMDA receptor. Concomitantly with the increased rate of apoptotic elimination of granule neurons, the activity of two death proteases of the caspase family, in particular of caspase 3 and caspase 1 at a lower extent, was remarkably increased in the cerebellum of the treated rats. On the contrary, a marker related to the normal differentiation process of granule neurons, the enzyme ornithine decarboxylase, was strongly decreased in its activity in the cerebellum of treated rat pups. 相似文献
56.
Hájos N Katona I Naiem SS MacKie K Ledent C Mody I Freund TF 《The European journal of neuroscience》2000,12(9):3239-3249
Using a new antibody developed against the C-terminus of the cannabinoid receptor (CB1), the immunostaining in the hippocampus revealed additional axon terminals relative to the pattern reported previously with an N-terminus antibody. Due to a greater sensitivity of this antibody, a large proportion of boutons in the dendritic layers displaying symmetrical (GABAergic) synapses were also strongly immunoreactive for CB1 receptors, as were axon terminals of perisomatic inhibitory cells containing cholecystokinin. Asymmetrical (glutamatergic) synapses, however, were always negative for CB1. To investigate the effect of presynaptic CB1 receptor activation on hippocampal inhibition, we recorded inhibitory postsynaptic currents (IPSCs) from principal cells. Bath application of CB1 receptor agonists (WIN55,212-2 and CP55,940) suppressed IPSCs evoked by local electrical stimulation, which could be prevented or reversed by the CB1 receptor antagonist SR141716A. Action potential-driven IPSCs, evoked by pharmacological stimulation of a subset of interneurons, were also decreased by CB1 receptor activation. We also examined the effects of CB1 receptor agonists on Ca2+-independent miniature IPSCs (mIPSC). Both agonists were without significant effect on the frequency or amplitude of mIPSCs. Synchronous gamma oscillations induced by kainic acid in the CA3 region of hippocampal slices were reversibly reduced in amplitude by the CB1 receptor agonist CP 55,940, which is consistent with an action on IPSCs. We used CB1-/- knock-out mice to confirm the specificity of the antibody and of the agonist (WIN55,212-2) action. We conclude that activation of presynaptic CB1 receptors decreases Ca2+-dependent GABA release, and thereby reduces the power of hippocampal network oscillations. 相似文献
57.
薄层扫描法测定三九感冒灵冲剂中对乙酰氨基酚及咖啡因的含量 总被引:6,自引:0,他引:6
目的 :用薄层扫描法同时测定三九感冒灵冲剂中对乙酰氨基酚及咖啡因的含量。方法 :以氯仿 -乙酸乙酯 -甲醇 -氨水(15∶4∶3∶0 3)为展开剂 ,采用双波长反射法锯齿扫描。结果 :对乙酰氨基酚平均回收率为99 33 % ,RSD=1 28% ,3批样品的标示量分别为99 02 %、98 48 %、99 23% ;咖啡因平均回收率为100 1 % ,RSD=1 71 % ,3批样品的标示量分别为99 74%、98 57 %、99 24%。结论 :本方法简便、快速 ,测定结果准确 ,可作为该制剂的质量控制方法 相似文献
58.
辛芩冲剂治疗变应性鼻炎的疗效和安全性分析 总被引:8,自引:0,他引:8
目的:探讨辛芩冲剂对变压性鼻炎的疗效和安全性。方法:确诊为变应性鼻炎的患者142例随机分成两组,试验组(112例)接受辛芩冲剂口服,一次5g,一日3次;对照组(30例)接受千柏鼻炎片口服,一次3片,一日3次,二种药物均用药20天。观察的症状包括喷嚏、流涕、鼻塞和鼻痒,并进行4分法评分,计算出治疗后积分改善率。结果:经过20天的治疗,辛芩冲剂治疗组的临床控制率为27.67%(31/112),显效率为43.75%(49/112),有效率为17.86%(20/112),无效率为10.71%(12/112),总有效率为89.29%(100/112);千柏鼻炎片治疗组的临床控制率为0%(0/30),显效率为6.67%(2/30),有效率为20.00%(6/30),无效率为73.33%(22/30),总有效率为26.67%(8/30)。经统计学处理两者差异有显著性意义(P<0.01),辛芩冲剂治疗组明显优于千柏鼻炎片治疗组,辛芩冲剂和千柏鼻炎片治疗组的病人均未发生不良反应。结论:辛芩冲具有疗效好、无毒副作用等优点,是治疗变应性鼻炎的理想药物。 相似文献
59.
新型药物开发制备过程中,需要对药物颗粒进行粒子设计,通过多层微胶囊化而得到复合包覆药物颗粒。药物包覆、微胶囊制备方法很多,可分为化学法、物理化学法、物理法。本文着重介绍了制备复合多层包覆药物颗粒的几种物理机械方法:复合杂化系统,高速椭圆转子混合法、喷流床包覆法。简要分析了该技术用于中药现代化加工的可能性。 相似文献
60.
目的 比较小青龙汤配方颗粒与传统饮片中芍药苷的含量。方法 采用高效液相色谱法进行分析比较研究。结果 该测定方法精密度、稳定性和重复性良好,平均回收率为101.78%,RSD=0.85%。结论 两种剂型中芍药苷的含量无明显差异。 相似文献