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41.
BACKGROUND: Interleukin-6 (IL-6) is a multifunctional cytokine which regulates immune responses and host defence mechanisms. IL-6 has been found to be increased in certain inflammatory conditions of the kidney, in which tubular epithelial cells play a pivotal role. Human renal tubular cells express IL-6. Until now no data about the effect of the immunosuppressant drug mycophenolic acid (MPA) on IL-6 expression were available. METHODS: Proximal and distal tubular epithelial cells (PTC/DTC) have been isolated immunomagnetically. Confluent monolayers were stimulated with interleukin-1beta (IL-1beta; 25 U/ml), IL-1beta+ MPA (0.25-50 micro M) or MPA alone for 48 h. Release of IL-6 protein into the supernatant was evaluated with an enzyme immunoassay, IL-6 mRNA expression was evaluated using the Quantikine mRNA kit. RESULTS: After IL-1beta stimulation, a highly significant 2.6- (PTC) and 3.8-fold (DTC) upregulation of IL-6 expression was detectable. IL-6 mRNA was upregulated by IL-1beta [1.57- (PTC) and 2.03-fold (DTC)]. MPA inhibited this cytokine-induced IL-6 expression in a dose-dependent manner. Incubation with the lowest MPA concentration had no effect on the stimulated upregulation, whereas all higher doses significantly decreased IL-6 expression. Dexamethasone significantly inhibited the cytokine-induced IL-6 protein release in PTC, but not in DTC. CONCLUSIONS: In this study we demonstrated for the first time an inhibitory effect of MPA on the stimulated IL-6 expression of renal tubular epithelial cells. In contrast to older data, which showed a synergistic upregulation of the expression of a CC-chemokine by a combination of cytokines and MPA, in the present study we could demonstrate an immunosuppressive effect of MPA on the expression of an important cytokine.  相似文献   
42.
目的应用抗核抗体独特型多肽免疫治疗狼疮肾炎小鼠,观察其对狼疮肾炎模型小鼠肾脏的保护作用。方法将35只雌性GVHD狼疮样肾炎小鼠(C57BL/10×DBA/2)F1分为3组,肾炎模型对照组(10只),口服多肽实验组(10只),皮下注射多肽实验组(15只)。3组小鼠均于24周龄处死,观察3组小鼠体质量、尿蛋白、肾脏组织学及血清IL-6水平的变化。结果在给予多肽12周时,皮下注射组和口服多肽组小鼠肾脏损害较对照组明显减轻;血清IL-6水平也较对照组明显降低。在给予多肽10周时,皮下注射组小鼠体质量明显高于对照组小鼠,12周时口服组体质量也明显高于对照组。给予多肽4周时,皮下注射组小鼠尿蛋白明显少于对照组,8周时口服组尿蛋白也明显少于对照组。结论口服独特型多肽对GVHD狼疮样肾炎小鼠肾脏同样有保护作用。  相似文献   
43.
Early multiple organ dysfunction syndrome appears to be facilitated with bacterial translocation in severely burn injury, yet the mechanisms of bacterial translocation remains in dispute. The aim of this study was to investigate the potential role of intestinal bifidobacteria in the pathogenesis of gut-derived bacteria/endotoxin translocation following burns and the effects of bifidobacterial supplement on gut barrier. Methods: Wistar rats were randomly divided into burn group (Burn, n=60),sham burn group (SB, n=10) in experiment Ⅰ , and burn + saline group (BS, n=30), burn + bifidobacteria group (BB, n=30), and sham-burn + saline group (SS, n= 10) in experiment Ⅱ. Animals in BB group were fed bifidobacterial preparation (5 × 109 CFU/ml) after burns, 1.5ml,twice daily. Animals in BS and SS were fed saline. Samples were taken on days 1, 3, and 5 in burn groups, and on day 3 in sham-burn groups. The incidence of bacteria/endotoxin translocation and counts of Bifidobacterium, Fungi and Escherichia coli in gut mucosa were determined with standard methods. The levels of sIgA in mucus of small intestine were measured by RIA. The positive sIgA expression in lamina propria and ileum mucosal injury was evaluated light microscopically by blinded examiners. Results: Our results showed that the incidence of bacterial translocation was increased after burns, which was accompanied by significant decrease in number of bifidobacteria but significant increase in E. coli and fungi in gut mucosa, and elevation of levels of plasma endotoxin and IL-6 (P<0. 001).The incidence of bacterial translocation was markedly reduced after 3- and 5-day supplementation of bifidobacteria compared with control group (P<0.05). The counts of mucosal bifidobacteria were increased by 4- to 40-fold,while E. coli and fungi were decreased by 2- to 30-fold and 10- to 150-fold, respectively, after bifidobacterial supplementation in contrast to control group. The damage of mucosa tended to be less pronounced after 3-day bifidobacteria-supplemented formula compared with control group [grade 2(0-6) vs. grade 4(3-6), P<0.05]. Moreover, the expression and release of sIgA was markedly augmented after 3-day bifidobacteria-supplementation formula and it returned to normal range on day 5. Conclusion: The decrease in counts and proportion of bifidobacteria in mucous membrane flora may play an important role in the development of bacteria/endotoxin translocation following thermal injury. The supplement of exogenous bifidobacteria could per se improve gut barriers, and attenuate bacteria/endotoxin translocation secondary to major burns.  相似文献   
44.
目的 研究在IL 2和IL 4作用下 ,趋化性细胞因子受体CCR3在人生发中心 (germinalcenter,GC)B细胞上的表达及其功能特性。方法 采用流式细胞术检测人GCB细胞上CCR3表达和在CCR3配体eotaxin作用下B细胞的凋亡 ,实时定量RT PCR和Northernblot法检测GCB细胞内CCR3mRNA的表达 ,淋巴细胞趋化和黏附试验检测B细胞的趋化和黏附能力。结果 人GCB细胞极低表达趋化性细胞因子受体CCR3,经IL 2和IL 4作用后 ,GCB细胞高表达CCR3,但此时CCR3不能在其配体作用下诱导GCB细胞的趋化和黏附功能 ,而是诱导GCB细胞凋亡。结论 IL 2和IL 4联合诱导人GCB细胞CCR3表达 ,CCR3可能具有死亡受体的功能。  相似文献   
45.
胃癌是最常见的癌肿之一,应用原位杂交技术检测胃癌组织中IL—6及其受体mRNA的表达情况,具有灵敏度高、特异性强的特点,而且较直观地在组织原位和转录水平对标本中IL—6及其受体进行研究,这使得形态学观察与功能学检测相结合,更能反映胃粘膜不同病变细胞分泌IL—6及其受体的情况。  相似文献   
46.
目的:探讨血清中白细胞介素4(IL-4)和白细胞介素13(IL-13)在支气管哮喘发病中的作用.方法:本研究对临床确诊的支气管哮喘46例,与正常对照组46例,分别抽取血清采用 ELISA 法测定其 IL-4、IL-13的含量.结果:支气管哮喘急性发作期病人和对照组正常人血清中的 IL-4水平分别为(460.84±27.11)和(132.97±24.66) ng/L,二组经 t 检验后 P<0.001.两组 IL-13 的水平分别为(23.76±5.44)和(12.61±2.49) ng/L,二组经 t 检验后 P<0.001.结论:哮喘病人 IL-4、IL-13 明显高于对照组,提示 IL-4、IL-13 对哮喘发病有一定的调控作用,对支气管哮喘气道非特异性炎症和局部免疫反应起重要作用.  相似文献   
47.
肺挫伤致肺水肿患者血浆中E-SLT,IL-8,TNF-α和ET-1的变化   总被引:1,自引:1,他引:0  
目的本研究观察胸部外伤所致肺水肿病人血中E-选择素、TNF、白细胞介素-8和内皮素的变化.方法用固相双夹心酶联免疫吸附法和放免技术共测定了24例胸部外伤病人在治疗前后血中E-选择素、肿瘤坏死因子、白细胞介素-8和内皮素浓度.结果临床肺水肿病人血中E-选择素、肿瘤坏死因子、白细胞介素-8和内皮素的浓度在发病时明显升高,与正常对照组比较,差异有显著性(P<0.001).治愈后恢复正常,治疗后各项指标与正常对照组比较差异无显著性(P>0.05),但治疗前后差异有显著性(P<0.001).结论E-选择素、肿瘤坏死因子、白细胞介素-8和内皮素在肺水肿发病机制中起着重要,随着这些因子的升高出现肺水肿并逐渐加重,这些因子降低后肺水肿逐步消失.因此对这些因子的检测有助于估计病情和评价疗效.  相似文献   
48.
目的 探讨白细胞介素 (IL) 2和B7 1双免疫基因转染肝癌细胞瘤苗免疫小鼠后获得的脾淋巴细胞经mIL 12基因修饰后治疗小鼠肝癌的可行性和疗效。方法 用 2 0 0PFU 细胞滴度的重组腺病毒载体 (Adv)将人IL 2和B7 1基因共同转染小鼠肝癌Hepal 6细胞株 ,经 80mg L丝裂霉素 (MMC)处理制备成肝癌细胞瘤苗 ,免疫同系小鼠后分离其脾淋巴细胞 (SLC) ,转染mIL 12基因 (Adv滴度 2 0 0PFU 细胞 )后注射入直径 1cm的小鼠皮下移植肝癌内 ,观察抗瘤效果。结果 转mIL 12基因SLC治疗组小鼠瘤体增加值最小 ( 0 .0 8± 0 .0 5 )cm3,与各对照组比差异有显著性 [(转染BGFP基因SLC、未转染SLC和生理盐水注射组分别为 ( 3 .46± 0 .15 ) ,( 3 .5 6± 0 .2 3)和( 8.12± 0 .5 4)cm3,P <0 .0 5 ]。结论 IL 2和B7 1双基因修饰肝癌瘤苗诱导小鼠产生的免疫脾淋巴细胞可能成为一种新的过继免疫治疗效应细胞及携带IL 12基因的载体细胞 ;基因治疗、特异性主动免疫和过继性细胞免疫治疗结合将有更优越的抗瘤效果。  相似文献   
49.
50.
The effect of Panaxatriol Ginsenoside (PTGS) on Immune functions in bone marrow suppressed mice induced by injection of cyclophosphamide (CY) has been studied. Bone marrow suppressed mice were made by injection of CY (150 mg/kg) parenterally. Subcutaneous injection of PTGS three days earlier partially restored the number and the activity of bone marrow cells, significantly enhanced the production of IL-1, IL- 3 and IL- 6 like substances and promoted the reactivity of murlne spleen cells to Con-A In bone marrow suppressed mice.  相似文献   
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