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61.
《Seminars in immunology》2016,28(4):384-393
Efforts to reverse the pathologic consequences of vulnerable plaques are often stymied by the complex treatment resistant pro-inflammatory environment within the plaque. This suggests that pro-atherogenic stimuli, such as LDL cholesterol and high fat diets may impart longer lived signals on (innate) immune cells that persist even after reversing the pro-atherogenic stimuli. Recently, a series of studies challenged the traditional immunological paradigm that innate immune cells cannot display memory characteristics. Epigenetic reprogramming in these myeloid cell subsets, after exposure to certain stimuli, has been shown to alter the expression of genes upon re-exposure. This phenomenon has been termed trained innate immunity or innate immune memory. The changed responses of ‘trained’ innate immune cells can confer nonspecific protection against secondary infections, suggesting that innate immune memory has likely evolved as an ancient mechanism to protect against pathogens. However, dysregulated processes of immunological imprinting mediated by trained innate immunity may also be detrimental under certain conditions as the resulting exaggerated immune responses could contribute to autoimmune and inflammatory diseases, such as atherosclerosis. Pro-atherogenic stimuli most likely cause epigenetic modifications that persist for prolonged time periods even after the initial stimulus has been removed. In this review we discuss the concept of trained innate immunity in the context of a hyperlipidemic environment and atherosclerosis. According to this idea the epigenome of myeloid (progenitor) cells is presumably modified for prolonged periods of time, which, in turn, could evoke a condition of continuous immune cell over-activation.  相似文献   
62.
《Seminars in immunology》2016,28(4):319-327
The plant innate immune system comprises local and systemic immune responses. Systemic plant immunity develops after foliar infection by microbial pathogens, upon root colonization by certain microbes, or in response to physical injury. The systemic plant immune response to localized foliar infection is associated with elevated levels of pattern-recognition receptors, accumulation of dormant signaling enzymes, and alterations in chromatin state. Together, these systemic responses provide a memory to the initial infection by priming the remote leaves for enhanced defense and immunity to reinfection. The plant innate immune system thus builds immunological memory by utilizing mechanisms and components that are similar to those employed in the trained innate immune response of jawed vertebrates. Therefore, there seems to be conservation, or convergence, in the evolution of innate immune memory in plants and vertebrates.  相似文献   
63.
Ethephon (2‐chloroethyl phosphonic acid) is a plant growth promoter used to control the plant growth process by liberating ethylene and stimulating the production of endogenous ethylene. Medicinal plants are sources of novel drug discovery targets. Costus (Saussurea lappa) has been used as traditional Chinese medicine. The current study was conducted to examine the possible modifying effects of costus (S. lappa) root aqueous extract against kidney toxicity induced by ethephon in male rats. A total of 50 adult male rats were divided into five groups (first, control; second, costus; third, ethephon; fourth, posttreated ethephon with costus; fifth, ethephon self‐healing). There is a significant increase in the serum levels of urea, creatinine, potassium ions, chloride ions, kidney injury, DNA damage, and proliferating cell nuclear antigen expressions in treated rats with ethephon when compared to the control group. In contrast, the treated rats with ethephon revealed a significant decrease in the levels of sodium ions and an insignificant decrease in the calcium ions. Saussurea lappa extract modified these alterations when compared to the control group. As a result, costus root extract significantly reduced rat kidney toxicity after ethephon administration. We recommend costus to be included in diet for its valuable effects, and also producers and consumers should become more aware about the toxic effects of ethephon.  相似文献   
64.
目的 分析血清microRNA-34a(mir-34a)、沉默信息调节因子1(Sirt1)水平与老年脑梗死患者颈动脉粥样硬化斑块稳定性的关系。方法 选取2018年2月~2019年2月内江市第一人民医院收治的102例老年脑梗死患者作为脑梗死组,另选取同期入院体检的50例健康者作为对照组。均行颈动脉超声检查,分为斑块形成组及斑块未形成组(其中又分为不稳定斑块组和稳定斑块组),并检测各组血清mir-34a、Sirt1水平。结果 脑梗死组血清mir-34a水平显著高于对照组,血清Sirt1水平显著低于对照组(P<0.05);斑块形成组血清mir-34a水平显著高于斑块未形成组,血清Sirt1水平显著低于斑块未形成组(P<0.05);血清mir-34a水平预测斑块形成的AUC值为0.913,敏感度及特异度为82.90%、85.70%;血清Sirt1水平预测斑块形成的AUC值为0.874,敏感度及特异度为71.40%、91.50%;不稳定斑块组血清mir-34a水平显著高于稳定斑块组,血清Sirt1水平显著低于稳定斑块组(P<0.05);血清mir-34a水平预测斑块稳定性的AUC值为0.767,敏感度及特异度为51.00%、90.90%;血清Sirt1水平预测斑块稳定性的AUC值为0.756,敏感度及特异度为57.60%、87.80%。结论 血清mir-34a、Sirt1水平异常与脑梗死患者颈动脉粥样硬化斑块形成及其稳定性密切相关,可将其作为脑梗死的预警指标。  相似文献   
65.
李剑  刘志刚  赵军  陈宁军 《西部医学》2020,32(9):1328-1332
【摘要】 目的 探讨微小RNA-212(miR-212)、沉默信息调节因子1(SIRT1)在垂体生长激素(GH)腺瘤患者血清中的表达水平及与预后的关系。方法 纳入2016年1月~2019年8月空军军医大学第一附属西京医院收诊的58例垂体GH腺瘤患者设为观察组,选取同期于本院体检的62例健康者设为健康组;采用实时荧光定量PCR(qRT-PCR)法检测所有研究对象血清miR 212、SIRT1、缺氧诱导因子-1α(HIF-1α)、血管内皮生长因子(VEGF)表达水平;比较不同预后垂体GH腺瘤患者血清miR-212、SIRT1、HIF-1α、VEGF水平;采用Pearson法分析垂体GH腺瘤患者血清miR-212、SIRT1表达水平与HIF-1α、VEGF相关性及miR-212表达水平与SIRT1的关系;采用受试者特征工作曲线(ROC)评价血清miR-212、SIRT1对垂体GH腺瘤患者预后的诊断价值。结果 观察组患者血清miR-212表达水平明显低于健康组(t=7.434,P<0.05),血清SIRT1、HIF-1α、VEGF表达水平明显高于健康组(P<0.05);未缓解组垂体GH腺瘤患者血清miR-212表达水平明显低于缓解组(P<0.05),血清SIRT1、HIF-1α、VEGF表达水平明显高于缓解组(t=2.536、3.242、2.638,P<0.05);垂体GH腺瘤患者血清miR-212表达水平与HIF-1α、VEGF、SIRT1水平均呈负相关(P<0.05),血清SIRT1表达水平与HIF-1α、VEGF呈正相关(P<0.05);血清miR-212、SIRT1水平对垂体GH腺瘤患者不良预后评估的曲线下面积(AUC)为0.873、0.862,对应截断值分别为0.52、1.94,此时对应灵敏度分别为81.3%、75.0%,特异度分别为88.1%、85.7%;两者联合诊断垂体GH腺瘤的AUC为0.938,其灵敏度、特异度分别为93.8%、81.0%。结论 垂体GH腺瘤血清miR-212表达下调,SIRT1表达上调,两者可能与HIF-1α、VEGF相互作用,进而协同垂体GH腺瘤发生与发展,miR-212、SIRT1有望成为评估垂体GH腺瘤预后的参考指标,两者联合检测可有效提高垂体GH腺瘤预后价值。  相似文献   
66.
目的探讨胃癌组织中沉默信息调节因子1(SIRT-1)和血管内皮生长因子(VEGF)的表达及临床意义。方法选取2016年6月至2018年6月本院胃癌患者120例,均接受胃癌手术切除术。采用免疫组化检测胃癌组织及其癌旁正常组织中SIRT-1、VEGF的表达。结果胃癌组织SIRT-1、VEGF表达阳性率明显高于癌旁正常组织,差异有统计学意义(P<0.05);胃癌组织SIRT-1、VEGF的表达与TNM分期、浸润深度、浆膜受侵、淋巴结转移有关(P<0.05),与性别、年龄、肿瘤位置、分化程度、肿瘤直径无关(P>0.05);胃癌组织SIRT-1与VEGF表达呈正相关(P<0.05)。结论胃癌组织中SIRT-1、VEGF呈高表达状态,且与胃癌的发生发展有关,可能共同促进了胃癌的生长、侵袭、转移等生物学行为。  相似文献   
67.
文题释义:自身免疫调节因子:基因分析显示由于单基因突变引起一种自身免疫病,此基因则被命名为自身免疫调节因子即AIRE基因。AIRE基因的突变或者缺失会造成胸腺内自身组织特异性抗原转录缺失,影响阴性选择,从而致使自身反应性T细胞逃逸外周,引起自身免疫反应。AIRE基因一直是免疫学相关研究中的热点。胸腺上皮细胞:胸腺上皮细胞分为髓质胸腺上皮细胞和皮质胸腺上皮细胞,二者均来源于胸腺上皮祖细胞,据研究报道髓质胸腺上皮细胞表达的AIRE基因调控着胸腺内的阴性选择,但是由于胸腺上皮祖细胞和胸腺上皮细胞不易分离且数量少,其应用和研究一直受限。该实验在体外将胚胎干细胞分化为胸腺上皮祖细胞,可以为相关研究提供细胞来源。  摘要背景:自身免疫性疾病主要是由于胸腺内自身组织特异性抗原持续表达缺失而引起强烈免疫应答的一类疾病,而胸腺功能减退和胸腺内组织特异性抗原的不稳定表达会限制治疗效果。胸腺组织主要由胸腺上皮细胞组成,但胸腺内成熟胸腺上皮细胞和胸腺上皮祖细胞有限的数量来源极大限制了相关研究。目的:研究小鼠胚胎干细胞向胸腺上皮祖细胞分化过程中自身免疫调节因子的表达变化。方法:采用两步分化方法定向诱导小鼠胚胎干细胞分化为内胚层再分化为胸腺上皮祖细胞,分别收集定向诱导分化第0,3,13天细胞,采用细胞免疫荧光、流式细胞术、Western blot、Real-Time PCR 检测相关基因及蛋白的表达变化。结果与结论:①诱导分化第0天,免疫荧光检测OCT4、SSEA1表达阳性;诱导分化第3天,免疫荧光检测SOX17、FoxA2呈双阳性表达;诱导分化第13天,流式细胞术检测EpCAM1、K5、K8表达阳性;②Real-time PCR检测小鼠胚胎干细胞定向分化过程中PAX1PAX9FOXN1PLET1基因表达逐渐增高;③Real-time PCR检测分化第0,3,13天AIRE基因表达升高,INS2GAD67基因表达也升高;④Western blot检测分化第0,3,13天AIRE蛋白表达降低,胰岛素蛋白、GAD67蛋白均无表达;⑤结果表明,小鼠胚胎干细胞成功分化为胸腺上皮祖细胞,且分化而来的胸腺上皮祖细胞中AIRE基因表达很高,促进了INS2GAD67基因的表达,为细胞移植治疗自身免疫性疾病提供评价依据。ORCID: 0000-0001-5253-3085(胡蓉) 中国组织工程研究杂志出版内容重点:干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程  相似文献   
68.
BACKGROUND AND AIMS: Cholestasis is one of the principal manifestations of liver disease and often results from disorders involving bile duct epithelia rather than hepatocytes. A range of disorders affects biliary epithelia, and no unifying pathophysiologic event in these cells has been identified as the cause of cholestasis. Here we examined the role of the inositol 1,4,5-trisphosphate receptor (InsP3R)/Ca(2+) release channel in Ca(2+) signaling and ductular secretion in animal models of cholestasis and in patients with cholestatic disorders. METHODS: The expression and distribution of the InsP3R and related proteins were examined in rat cholangiocytes before and after bile duct ligation or treatment with endotoxin. Ca(2+) signaling was examined in isolated bile ducts from these animals, whereas ductular bicarbonate secretion was examined in isolated perfused livers. Confocal immunofluorescence was used to examine cholangiocyte InsP3R expression in human liver biopsy specimens. RESULTS: Expression of the InsP3R was selectively lost from biliary epithelia after bile duct ligation or endotoxin treatment. As a result, Ca(2+) signaling and Ca(2+)-mediated bicarbonate secretion were lost as well, although other components of the Ca(2+) signaling pathway and adenosine 3',5'-cyclic monophosphate (cAMP)-mediated bicarbonate secretion both were preserved. Examination of human liver biopsy specimens showed that InsP3Rs also were lost from bile duct epithelia in a range of human cholestatic disorders, although InsP3R expression was intact in noncholestatic liver disease. CONCLUSIONS: InsP3-mediated Ca(2+) signaling in bile duct epithelia appears to be important for normal bile secretion in the liver, and loss of InsP3Rs may be a final common pathway for cholestasis.  相似文献   
69.
70.
Regulators that play an important role in the differentiation and development of plants or invertebrates may also affect the differentiation of human leukaemia cells through a common signal transduction system, and might be clinically useful for treating acute myeloid leukaemia. Cotylenin A has been isolated as a plant growth regulator. We examined the effects of cotylenin A on the differentiation of several myelogenous leukaemia cells, and found that cotylenin A is a potent and novel inducer of the monocytic differentiation of human myeloid leukaemia cells. Cotylenin A induced the functional and morphological differentiation of myeloblastic and promyelocytic leukaemia cells, but did not effectively induce the differentiation of monocytoid leukaemia cells. Cotylenin A-induced differentiation was not affected by several inhibitors of signal transduction, suggesting that this inducer exhibits a unique mode of action.  相似文献   
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