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排序方式: 共有638条查询结果,搜索用时 31 毫秒
1.
目的:探讨唑来膦酸(zoledronate,ZOL)对破骨细胞分化中钙调蛋白(calmodulin)和钙调磷酸酶(calcineurin)基因表达的影响?方法:小鼠RAW264.7细胞分为A?B两组,均用100 ng/mL核因子κB受体激活蛋白配体(RANKL)诱导4 d;B组细胞在RANKL 诱导第2天加入1×10-6 mol/L ZOL处理48 h?RANKL 诱导4 d后收获细胞,检测破骨细胞生成及calmodulin?calcineurin基因表达情况?结果:B组多核破骨细胞数?吸收陷窝数目及面积分别为(8.8 ± 2.3)个?(6.7 ± 1.2)个和(997.1 ± 14.8)μm2,均显著低于A组的(19.7 ± 2.9)个?(13.3 ± 1.5)个和(1 676.9 ± 24.9) μm2(P < 0.01)?B组calmodulin mRNA及蛋白水平较A组分别降低了51.0%和78.7%(P < 0.05),calcineurin则分别下降了37.0%和69.5%(P < 0.01)?免疫荧光细胞化学显示,B组calmodulin?calcineurin的荧光强度较A组也明显下降?结论:ZOL可显著抑制破骨细胞生成,并下调破骨细胞分化中calmodulin和calcineurin的mRNA和蛋白水平,而calmodulin?calcineurin可能参与了ZOL对破骨细胞形成和功能的抑制?  相似文献   
2.
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3.
In this final of a 5-part Focus Seminar series on precision medicine, we focus on catecholaminergic polymorphic ventricular tachycardia (CPVT). This focus on CPVT allows us to take a “deep dive” and explore the full extent of the precision medicine opportunities for a single cardiovascular condition at a level that was not possible in the preceding articles. As a new paradigm presented in this article, it has become clear that CPVT can occur as either a typical or atypical form. Although there is a degree of overlap between the typical and atypical forms, it is notable that they arise due to different underlying genetic changes, likely exhibiting differing mechanisms of action, and presenting with different phenotypic features. The recognition of these differing forms of CPVT and their different etiologies and mechanisms is an important step toward implementing rapidly emerging precision medicine approaches that will tailor novel therapies to specific gene defects.  相似文献   
4.
Pancreatic cancer is highly malignant with limited therapy and a poor prognosis. TRAIL-activating therapy has been promising, however, clinical trials have shown resistance and limited responses of pancreatic cancers. We investigated the effects of calmodulin(CaM) antagonists, trifluoperazine(TFP) and tamoxifen(TMX), on TRA-8-induced apoptosis and tumorigenesis of TRA-8-resistant pancreatic cancer cells, and underlying mechanisms. TFP or TMX alone did not induce apoptosis of resistant PANC-1 cells, while they dose-dependently enhanced TRA-8-induced apoptosis. TMX treatment enhanced efficacy of TRA-8 therapy on tumorigenesis in vivo. Analysis of TRA-8-induced death-inducing-signaling-complex (DISC) identified recruitment of survival signals, CaM/Src, into DR5-associated DISC, which was inhibited by TMX/TFP. In contrast, TMX/TFP increased TRA-8-induced DISC recruitment/activation of caspase-8. Consistently, caspase-8 inhibition blocked the effects of TFP/TMX on TRA-8-induced apoptosis. Moreover, TFP/TMX induced DR5 expression. With a series of deletion/point mutants, we identified CaM antagonist-responsive region in the putative Sp1-binding domain between −295 to −300 base pairs of DR5 gene. Altogether, we have demonstrated that CaM antagonists enhance TRA-8-induced apoptosis of TRA-8-resistant pancreatic cancer cells by increasing DR5 expression and enhancing recruitment of apoptotic signal while decreasing survival signals in DR5-associated DISC. Our studies support the use of these readily available CaM antagonists combined with TRAIL-activating agents for pancreatic cancer therapy.  相似文献   
5.
目的探讨蛋白激酶A(PKA)/钙调蛋白Ⅱ(CaMKⅡ)信号通路在二甲双胍(Met)调节2型糖尿病(T2DM)大鼠心房小电导钙激活钾通道亚型KCa2.2和KCa2.3蛋白表达中的作用。方法健康雄性Wistar大鼠40只,随机选8只喂普通饲料为对照组(Con组),另32只喂高脂高糖饲料联合腹腔注射小剂量链脲佐菌素构建T2DM大鼠模型后,再随机分为DM组、Met组、H-89组(腹腔注射PKA抑制剂H-89)和KN-93组(腹腔注射CaMKⅡ抑制剂KN-93),每组8只。用ELISA检测大鼠心房组织PKA活性,qRT-PCR检测CaMKⅡmRNA表达,Western blot和免疫组织化学检测KCa2.2、KCa2.3和磷酸化CaMKⅡ(p-CaMKⅡ)蛋白表达。结果 Con组、DM组、Met组和H-89组PKA活性分别为0.74±0.04、0.50±0.05、0.69±0.03和0.48±0.03。与DM组比较,Met组PKA活性明显提升(P<0.01);与Met组比较,H-89组显著抑制PKA活性(P<0.01)。Con组、DM组及Met组CaMKⅡmRNA分别为1.00±0.07、0.61±0.03和0.92±0.09。与Con组比较,DM组CaMKⅡmRNA表达明显降低(P<0.01);与DM组比较,Met组CaMKⅡmRNA表达明显增加(P<0.01)。与Con组比较,DM组心房组织p-CaMKⅡ和KCa2.2蛋白表达均明显降低,KCa2.3蛋白表达明显升高(P<0.01)。与DM组比较,Met组明显提升p-CaMKⅡ和KCa2.2蛋白表达,明显抑制KCa2.3蛋白表达(P<0.01)。与Met组比较,KN-93组和H-89组分别显著抑制p-CaMKⅡ蛋白表达和PKA活性,均显著下调KCa2.2蛋白表达,上调KCa2.3蛋白表达(P<0.01)。免疫组织化学染色显示,与Met组比较,KN-93组和H-89组均显著下调KCa2.2蛋白表达,上调KCa2.3蛋白表达(P<0.05,P<0.01),与Western blot检测结果一致。结论 Met通过激活PKA/CaMKⅡ信号通路部分修复T2DM大鼠心房KCa2.2蛋白下调和KCa2.3蛋白上调。  相似文献   
6.
Control of cardiomyocyte cytosolic Ca2+ levels is crucial in determining inotropic status and ischemia/reperfusion stress response. Responsive to fluctuations in cellular Ca2+, Ca2+/calmodulin‐dependent protein kinase II (CaMKII) is a serine/threonine kinase integral to the processes regulating cardiomyocyte Ca2+ channels/transporters. CaMKII is primarily expressed either in the δB or δC splice variant forms, which may mediate differential influences on cardiomyocyte function and pathological response mechanisms. Increases in myocyte Ca2+ levels promote the binding of a Ca2+/calmodulin complex to CaMKII, to activate the kinase. Activity is also maintained through a series of post‐translational modifications within a critical region of the regulatory domain of the protein. Recent data indicate that the post‐translational modification status of CaMKIIδB/δC variants may have an important influence on reperfusion outcomes. This study provided the first evidence that the specific type of CaMKII post‐translational modification has a role in determining target selectivity of downstream Ca2+ transporters. The study was also able to demonstrate that the phosphorylated form of CaMKII closely co‐localizes with CaMKIIδB in the nuclear/myofilament fraction, contrasting with a co‐enrichment of oxidized CaMKII in the membrane fraction with CaMKIIδC. It has also been possible to conclude that a hyper‐phosphorylation of CaMKII (Thr287) in reperfused hearts represents a hyper‐activation of the CaMKIIδB, which exerts anti‐arrhythmic actions through an enhanced capacity to selectively increase sarcoplasmic reticulum Ca2+ uptake and maintain cytosolic Ca2+ levels. This suggests that suppression of global CaMKIIδ may not be an efficacious approach to developing optimal pharmacological interventions for the vulnerable heart.  相似文献   
7.
目的:以下丘脑-垂体-性腺轴为基础,探究右归丸对肾阳虚大鼠的药理作用,探讨其补肾填精的作用机制。方法:SD大鼠60只,采用氢化可的松建立肾阳虚模型大鼠,随机分为6组,分别为正常组、模型组、甲基睾酮(0.5 g·kg-1)组、右归丸低、中、高剂量组(0.5,1.0,2.5 g·kg-1),每组10只。造模后连续ig给药30 d,分别于给药第15,30天进行强迫负重游泳实验;第30天,眼球取血,放射免疫分析法检测大鼠血清睾酮(testosterone,T)、雌二醇(estradiol,E2)的含量;采用RT-PCR法检测各组大鼠下丘脑、垂体和靶腺(睾丸)钙调蛋白(Ca M)mRNA的表达。结果:与正常组比,模型组大鼠的负重游泳时间减少(P0.05),明显升高血清中E2的激素水平及降低T的激素水平(P0.05),明显升高下丘脑、垂体、睾丸中Ca M mRNA的表达(P0.05);与模型组比,甲基睾酮组、右归丸低、中、高剂量组可明显提高肾阳虚模型大鼠的负重游泳时长(P0.05),给药20 d后其体能趋于正常;给药20 d后甲基睾酮组、右归丸低、中、高剂量组可明显降低血清中E2的激素水平及升高T的激素水平(P0.05),明显降低下丘脑、垂体、睾丸中Ca M mRNA的表达(P0.05)。结论:右归丸可通过调节机体下丘脑-垂体-性腺轴中钙调蛋白基因表达,改善阳虚大鼠激素水平,逆转肾阳虚状态,具有补肾填精的作用。  相似文献   
8.
Lead (Pb) is a persistent environmental pollutant that has a structure and charge similar to many ions, such as calcium, that are essential for normal cellular function. Pb may compete with calcium for protein binding sites and inhibit signaling pathways within the cell affecting many organ systems including the immune system. The aim of the current study was to assess whether the calcium/calmodulin pathway is a principal target of environmentally relevant Pb during pro-inflammatory activation in a RAW 264.7 macrophage cell line. RAW 264.7 cells were cultured with 5 μM Pb(NO3)2, LPS, rIFNγ, or LPS+rIFNγ for 12, 24, or 48 hr. Intracellular protein signaling and multiple functional endpoints were investigated to determine Pb-mediated effects on macrophage function. Western blot analysis revealed that Pb initially modulated nuclear localization of NFκB p65 and cytoplasmic phosphorylation of CaMKIV accompanied by increased phosphorylation of STAT1β at 24 hr. Macrophage proliferation was significantly decreased at 12 hr in the presence of Pb, while nitric oxide (NO) was significantly reduced at 12 and 24 hr. Cells cultured with Pb for 12, 24, or 48 hr exhibited altered cytokine levels after specific stimuli activation. Our findings are in agreement with previous reports suggesting that macrophage pro-inflammatory responses are significantly modulated by Pb. Further, Pb-induced phosphorylation of CaMKIV (pCaMKIV), observed in the present study, may be a contributing factor in metal-induced autophagy noted in our previous study with this same cell line.  相似文献   
9.
林启鹏  朱茜  马立伟 《武警医学》2019,30(2):124-127
 目的 比较肌萎缩侧索硬化的两种不同基因突变型(C9orf72与CHMP2B)表达谱差异来探讨该类疾病可能的发病机制及治疗靶点。方法 从GEO数据库中下载C9orf72基因突变肌萎缩侧索硬化数据集(GSE68605)及CHMP2B基因突变肌萎缩侧索硬化数据集(GSE19332)。使用R软件(3.5.0版本)、Cytoscape 3.6.1软件及在线工具(DAVID及STRING)进行数据分析。结果 从两个数据集中,获得了11个样本,其中8个为C9orf72基因突变,3个为CHMP2B基因。发现了13个差异表达基因,在GO及KEGG功能富集分析中发现仅有CALM1-3及RYR2富集在钙离子检测、通过钙离子释放的调节影响心肌的收缩功能等。其中钙调蛋白是引起C9orf72基因突变肌萎缩侧索硬化及CHMP2B基因突变肌萎缩侧索硬化差异的关键蛋白。结论 CALM基因在C9orf72基因突变肌萎缩侧索硬化患者中高表达,钙调蛋白可能是诊断及治疗C9orf72基因突变肌萎缩侧索硬化患者的重要靶点。  相似文献   
10.
Background: In the simple ascidian chordate Ciona, the signaling pathways and gene regulatory networks giving rise to initial notochord induction are largely understood and the mechanisms of notochord morphogenesis are being systematically elucidated. The notochord has generally been thought of as a non‐compartmentalized or regionalized organ that is not finely patterned at the level of gene expression. Quantitative imaging methods have recently shown, however, that notochord cell size, shape, and behavior vary consistently along the anterior‐posterior (AP) axis. Results: Here we screen candidate genes by whole mount in situ hybridization for potential AP asymmetry. We identify 4 genes that show non‐uniform expression in the notochord. Ezrin/radixin/moesin (ERM) is expressed more strongly in the secondary notochord lineage than the primary. CTGF is expressed stochastically in a subset of notochord cells. A novel calmodulin‐like gene (BCamL) is expressed more strongly at both the anterior and posterior tips of the notochord. A TGF‐β ortholog is expressed in a gradient from posterior to anterior. The asymmetries in ERM, BCamL, and TGF‐β expression are evident even before the notochord cells have intercalated into a single‐file column. Conclusions: We conclude that the Ciona notochord is not a homogeneous tissue but instead shows distinct patterns of regionalized gene expression. Developmental Dynamics 243:612–620, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
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