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51.
目的 探讨川芎嗪预先给药对胎鼠海马神经细胞缺氧/复氧时c-fos和热休克蛋白70(HSP70)表达的影响.方法 胎鼠海马神经细胞培养鉴定后,随机分为5组(n=24):正常对照组(C组)、缺氧/复氧损伤组(A/R组)、不同浓度川芎嗪预先给药组(L组、M组和H组).C组不制备缺氧/复氧模型;A/R组、L组、M组和H组制备缺氧/复氧模型;L组、M组和H组加入川芎嗪,终浓度分别为60、200和800μg/ml,孵育1 h后制备缺氧/复氧模型.缺氧/复氧模型制备方法:海马神经细胞置入90%N2-10%CO2培养箱中孵育2 h诱导缺氧,然后放入37 ℃、5%CO2培养箱中复氧24 h.处理结束后测定海马神经细胞凋率、细胞活力、c-fos和HSP70的表达水平.结果 与C组比较,A/R组、L组和H组海马神经细胞活力降低,细胞凋亡率升高(P<0.01);与A/R组比较,L组、M组和H组海马神经细胞活力升高,细胞凋亡率降低,c-fos表达下调,HSP70表达上调(P<0.05);与L组比较,M组和H组海马神经细胞活力升高,细胞凋亡率降低,c-fos表达下调,HSP70表达上调(P<0.05);与M组比较,H组细胞活力下降,细胞凋亡率升高,c-fos表达上调,HSP70表达下调(P<0.01).结论川芎嗪预先给药抑制胎鼠海马神经细胞缺氧/复氧时细胞凋亡的机制可能与下调c-fos表达,上调HSP70表达有关. 相似文献
52.
目的:观察回阳生肌膏水、醇提取物对人慢性皮肤溃疡创缘成纤维细胞(uHFB)增殖的影响,并探讨其对c-fos、c-myc表达的影响.方法:组织块法培养uHFB;alarmar blue摄入法检测回阳生肌膏水、醇提取物对uHFB的增殖作用;免疫细胞化学方法检测二者对c-fos、c-myc表达的影响.结果:与对照组比,回阳生肌膏醇、水提取物分别在0.027~0.213 mg/L和0.15~1.2 mg/L浓度范围内对uHFB有促增殖作用(P<0.05或P<0.01);醇提物组c-fos蛋白在2 h达峰值,水提物组c-fos蛋白在1-3 h内持续增加至醇提物组2 h时水平;水、醇提物组c-myc蛋白在2-3 h内均增加,但醇提物组的表达强度高于水提物组.结论:回阳生肌膏可能通过上调核转录因子表达正向调控修复细胞增殖,加速创面愈合. 相似文献
53.
海马区c-fos基因表达在大鼠脑创伤后认知功能障碍中的作用 总被引:2,自引:0,他引:2
目的 探讨大鼠脑创伤后海马区c-fos基因表达及对学习记忆功能的影响.方法 建立Marmarou大鼠脑创伤模型,采用分子原位杂交技术和Morris水迷宫分别观察大鼠伤后海马区c-fos基因表达变化及空间学习记忆能力的改变. 结果 伤后30 min海马区神经元即出现c-fos mRNA的表达,1~3 h达高峰,伤后24 h表达基本消失;Morris水迷宫实验,大鼠伤后存在空间学习记忆功能障碍.结论 脑创伤可引起c-fos基因在海马区的表达上调,通过介导延迟性神经元细胞死亡,影响细胞间的信息传递,参与认知功能的损害. 相似文献
54.
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56.
目的 为探讨糖皮质激素(GCS)对脑内神经细胞的作用提供形态学资料.方法 动物行为学观察、免疫组化法神经细胞染色和形态计量学方法.结果 在大鼠后爪掌面皮下注射2.5%甲醛20μl可造成注射处急性持续性炎症.1h后,双侧中缝大核、丘脑、大脑皮层fos样免疫阳性神经元总数明显上升.用地塞米松预处理2h后可使相应部位FLI神经元数明显降低,具有剂量依赖性.外周水肿、疼痛表现与脑内FLI细胞数呈正相关.用糖皮质激素受体阻断剂RU486可部分反转GCS的效应.结论 ①伤害性刺激可引起中枢神经系统c-fos广泛表达;②GCS对中枢神经元c-fos表达的效应有差异性. 相似文献
57.
Timofeeva E Picard F Duclos M Deshaies Y Richard D 《The European journal of neuroscience》2002,15(6):1013-1029
The present study was conducted to investigate the pattern of neuronal activation and corticotropin‐releasing hormone (CRH) expression in fed, food deprived and refed lean (Fa/?) and obese (fa/fa) Zucker rats. The pattern of neuronal activation was studied by measuring the expression of the immediate‐early gene c‐fos. Expression of c‐fos and CRH mRNA was determined by in situ hybridization histochemistry. In both lean and obese rats, one hour of refeeding led to a transient increase in c‐fos mRNA levels which was detected in the paraventricular hypothalamic nucleus (PVH), the dorsomedial hypothalamic nucleus, the supraoptic nucleus, the paraventricular thalamic nucleus, the central nucleus of amygdala (CeA), the lateral and medial parabrachial nuclei, the nucleus of the solitary tract, and the area postrema. In addition, refeeding led to strong activation of the arginine‐vasopressin neurons located in the magnocellular part of the PVH. Following 24 h of food deprivation, CRH expression in the parvocellular division of the PVH was significantly higher in obese rats compared to lean animals. During refeeding, PVH CRH mRNA levels in obese rats decreased to reach control values. The decrease in CRH expression in obese rats was accompanied by the alleviation of the hypercorticosteronemia that characterized obese Zucker rats. CRH mRNA levels in the central nucleus of the amygdala were significantly higher in lean rats than in obese animals, when the rats were fed ad libitum During food deprivation, CeA CRH mRNA levels decreased in lean rats and gradually returned to predeprivation values during refeeding. In refed obese rats, CeA levels of CRH mRNA were higher than those of ad libitum fed or food‐deprived obese mutants. In the perifornical region of the lateral hypothalamic area (LHA), the expression of CRH mRNA rose significantly in response to refeeding in lean rats, but not in obese animals. Following the first hour of refeeding, the number of neurons expressing CRH mRNA in the LHA in lean rats almost doubled. The present results demonstrate that refeeding has a stimulating effect in obese Zucker rats in a pattern of activation similar to that seen in lean Fa/? rats. They also demonstrate differences in CRH expression between Fa/? and fa/fa rats after refeeding. The most apparent of these differences was seen in the lateral hypothalamus in which refeeding failed to up‐regulate CRH expression in obese rats. 相似文献
58.
Bacciottini L Passani MB Giovannelli L Cangioli I Mannaioni PF Schunack W Blandina P 《The European journal of neuroscience》2002,15(10):1669-1680
The effects of histaminergic ligands on both ACh spontaneous release from the hippocampus and the expression of c-fos in the medial septum-diagonal band (MSA-DB) of freely moving rats were investigated. Because the majority of cholinergic innervation to the hippocampus is provided by MSA-DB neurons, we used the dual-probe microdialysis technique to apply drugs to the MSA-DB and record the induced effects in the projection area. Perfusion of MSA-DB with high-KCl medium strongly stimulated hippocampal ACh release which, conversely, was significantly reduced by intra-MSA-DB administration of tetrodotoxin. Histamine or the H2 receptor agonist dimaprit, applied directly to the hippocampus, failed to alter ACh release. Conversely, perfusion of MSA-DB with these two compounds increased ACh release from the hippocampus. Also, thioperamide and ciproxifan, two H3 receptor antagonists, administered into MSA-DB, increased the release of hippocampal ACh, whereas R-alpha-methylhistamine, an H3 receptor agonist, produced the opposite effect. The blockade of MSA-DB H2 receptors, caused by local perfusion with the H2 receptor antagonist cimetidine, moderated the spontaneous release of hippocampal ACh and antagonized the facilitation produced by H3 receptor antagonists. Triprolidine, an H1 receptor antagonist, was without effect. Moreover, cells expressing c-fos immunoreactivity were significantly more numerous in ciproxifan- or thioperamide-treated rats than in controls, although no colocalization of anti-c-fos and anti-ChAT immunoreactivity was observed. These results indicate a role for endogenous histamine in modulating the cholinergic tone in the hippocampus. 相似文献
59.
艾灸对实验性类风湿关节炎滑膜细胞原癌基因 c-fos和c-myc mRNA表达的影响 总被引:2,自引:0,他引:2
目的观察艾灸对实验性类风湿关节炎滑膜细胞原癌基因c-fos、c-myc mRNA表达的影响,初步探讨艾灸对RA滑膜细胞内分子信号传导的调控.方法在日本大耳白兔右后足踝关节部皮内注射福氏完全佐剂造模,经过艾灸治疗,通过半定量RT-PCR测定c-fos和c-myc mRNA的表达量.结果治疗组c-fos和c-myc mRNA表达量显著低于造模组(P<0.01).结论艾灸治疗能够降低c-fos和c-myc mRNA的表达,影响生长因子信号传导系统. 相似文献
60.
目的探索大鼠脑干中缝核群星形胶质细胞对睡眠剥夺(SD)的反应及其与神经元的关系。方法采用小平台水环境法建立大鼠SD模型,分为睡眠剥夺12h(SD)组,睡眠剥夺12h恢复睡眠3h(SR)组及大平台对照(TC)组和正常单独饲养(CC)组,每组3只。用免疫组化的方法观察c-fos和胶原纤维酸性蛋白(GFAP)在脑干中缝核群的表达,及其与5-羟色胺(5-HT)阳性神经元的关系。结果GFAP在中缝核群尤其是中缝背核表达明显增多,睡眠恢复后表达明显减少,其变化趋势及部位与c-fos基因表达相一致。在中缝背核形成3种形式的复合体样结构:(1)c-fos(+)、5-HT(+)、GFAP(+);(2)5-HT(+)、GFAP(+)、c-fos(-);(3)5-HT(-)、GFAP(+)、c-fos(+)。结论GFAP对睡眠剥夺和恢复睡眠的影响反应敏感,与神经元反应趋势一致,提示星形胶质细胞和神经元可能共同参与睡眠调节。 相似文献