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41.
桑色素对小鼠T细胞增殖、周期和巨噬细胞分泌NO的影响   总被引:2,自引:0,他引:2  
目的:研究桑色素(morin)对小鼠T细胞增殖、细胞周期和腹腔巨噬细胞分泌一氧化氮(nitrogen monoxidum,NO)的影响.方法:以佛波醇酯(phorbol 12,13-dibutyrate,PDB)和离子霉素(ionomycin,Ion)联合刺激淋巴结来源的小鼠T淋巴细胞,再以不同终浓度的morin与上述细胞共培养,利用流式细胞术(FCM),以羧基荧光素双醋酸盐琥珀酰脂(carboxyfluorescein diacetate succinimide ester,CFDA-SE)染色检测T细胞的增殖;以碘化丙锭(propidiumiodide,PI)染色分析T细胞的细胞周期;脂多糖(Lipopolysaccharide,LPS)刺激小鼠腹腔巨噬细胞,与不同浓度morin共培养,以Griess反应检测上清液中的NO含量.结果:CFDA-SE染色分析显示,PDB Ion组的增殖指数(proliferation index,PI)为1.70±0.05,各浓度的morin对PDB Ion刺激的T细胞增殖,具有明显地抑制作用,以100 μmol/L的morin抑制作用最明显,PI为1.03±0.01(P<0.01).细胞周期的分析结果表明,morin组中处于S期的细胞比率较高,与PDB Ion组相比有明显差异.Griess反应检测NO含量的结果显示,各浓度组的morin均抑制LPS刺激巨噬细胞产生NO,100 μmol/L的morin可将LPS刺激巨噬细胞产生NO为(12.89±0.11)μmol/L降低为(7.25±0.05)μmol/L,抑制作用最强.结论:Morin可显著抑制PDB Ion刺激的T细胞增殖;其对增殖的抑制作用主要表现为S期的细胞的阻滞;对LPS刺激巨噬细胞产生的NO也有显著的抑制作用.  相似文献   
42.
目的:研究姜黄素对人低分化鼻咽癌细胞系亚克隆株CNE-2Z—HS裸鼠移植瘤生长和增殖的影响。方法:复制人低分化鼻咽癌细胞系亚克隆株CNE-2Z-H5裸鼠移植瘤模型,观察姜黄素对移植瘤生长的影响。结果裸鼠体内实验显示姜黄素可以抑制移植瘤的生长。不同浓度姜黄素组移植瘤瘤重与溶剂对照组比较有降低趋势,高剂量组降低更明显,差异有极显著性(P〈O.001),抑瘤率达59.75%。结论姜黄素可以抑制CNE-2Z—H5细胞裸鼠移植瘤的生长,其可能在鼻咽癌的治疗中具有一定的价值,值得进一步深入研究。  相似文献   
43.
菠萝蜜嫩茎离体培养的研究   总被引:3,自引:0,他引:3  
在成龄的菠萝蜜树茎干上取徒长的嫩茎为外植体,研究了菠萝蜜嫩茎离体培养的条件.结果表明:外植体芽萌发的最适培养基为MS 6-BA 2.0 mg.L-1 KT 1.0 mg.L-1 NAA 0.5mg.L-1;暗培养有助于芽的萌发;芽增殖的较适宜培养基为MS 6-BA 2.0 mg.L-1 KT 1.0mg.L-1 NAA 0.1 mg.L-1,连续培养7代后,其芽的平均增殖系数为4.3;本试验中增殖芽的诱导生根较难,还有待进一步地研究.  相似文献   
44.
Plasmin(ogen)wasknownforitsfibrinolyticactivityaswellasitsω aminocarboxylicacid bindingability.Onehighand 4low affinitybindingsitesweredetectedinplasminogenheavychain .Concur rently 5highlyhomologoustripleloopstructuresnamedaskringledomainswerefoundforming…  相似文献   
45.
瞬态电磁脉冲对细胞增殖的影响   总被引:3,自引:0,他引:3  
实验采用有丝分裂指数测定法及^3H-TdR掺入法,研究瞬态电磁脉冲对人外周血淋巴细胞及艾氏腹水癌细胞增殖的影响。结果发现,没有植物凝集素PHA时,100kHz和200kHz瞬态电磁脉冲对淋巴细胞有丝分裂指数和^3H-TdR掺入量无显著影响;有PHA时,100kHz瞬态电磁脉冲促进淋巴细胞摄取^3H-TdR,细胞有丝分裂指数增加,200kHz瞬态电磁脉冲抑制淋巴细胞摄取^3H-TdR,细胞有丝分裂指  相似文献   
46.
IntroductionBiomaterialsarealwaysusedinanenvironmentadjacenttolivingtissuesandblood.Celularinteractionswithimplantsareofprima...  相似文献   
47.
After primary mouse osteoblasts and ROS osteo-like cells were exposed to 50 Hz low frequency electromagnetic fields (EMF), the MTT method and flow cytometry have been used to determine cell proliferation, cell cycle and apoptosis. The results show that, compared with the control, the cells after exposure are more abundant, have larger S phase ratios and lower apoptosis ratios. The results indicate that EMF has an important biological effect which influences cell proliferation and cell cycle.  相似文献   
48.
Oestrogens are known to enhance angiotensin biosynthesis by increasing the elaboration of its precursor, angiotensinogen. On the other hand, we found that inhibition of angiotensin-converting enzyme (ACE) suppressed the proliferative response of the rat anterior pituitary gland to oestrogens. To answer the question whether the angiotensin system is involved in the control of the cell proliferation of the uterine epithelium, the effects of an ACE inhibitor, enalapril maleate, and of angiotensins II and IV, alone or together with losartan, an antagonist of angiotensin receptor type 1 (AT1), on endometrial epithelial cell proliferation have been studied. The experiments were performed on ovariectomized female Wistar rats. In the first experiment the animals were injected with a single dose of oestradiol benzoate or received an injection of solvent only. Half of the oestrogen-treated rats were injected additionally with enalapril maleate (EN, twice daily). The incorporation of bromodeoxyuridine (BrDU) into endometrial cell nuclei was used as an index of cell proliferation. It was found that oestradiol alone dramatically increased the BrDU labelling index (LI) of endometrial cell nuclei, and this effect was partially blocked by the simultaneous treatment with EN. In the second experiment, the animals were injected intraperitoneally with angiotensin II (AII), angiotensin IV (AIV) or saline, alone or together with losartan. It was found that AIV induced an increase in the LI in uterine epithelium, and this effect was not blocked by the simultaneous treatment with losartan. The increase in LI in uterine epithelium was also observed in the rats treated with AII and with losartan. These findings suggest an involvement of angiotensin IV in the control of uterine epithelium cell proliferation. Received 12 October 1998; received after revision 6 January 1999; accepted 2 February 1999  相似文献   
49.
It has been proposed that neuroinflammation, among other factors, may trigger an aberrant neuronal cell cycle re-entry leading to neuronal death. Cell cycle disturbances are also detectable in peripheral cells from Alzheimer’s disease (AD) patients. We previously reported that the anti-inflammatory 15- deoxy-Δ12,14-prostaglandin J 2 (15d-PGJ 2) increased the cellular content of the cyclin-dependent kinase inhibitor p27, in lymphoblasts from AD patients. This work aimed at elucidating the mechanisms of 15d-PGJ 2-induced p27 accumulation. Phosphorylation, half-life, and the nucleo-cytoplasmic traffic of p27 protein were altered by 15d-PGJ2 by mechanisms dependent on PI3K/Akt activity. 15d-PGJ 2 prevents the calmodulin-dependent Akt overactivation in AD lymphoblasts by blocking its binding to the 85-kDa regulatory subunit of PI3K. These effects of 15d-PGJ 2 were not mimicked by 9,10-dihydro-15-deoxy-Δ12,14- prostaglandin J 2, suggesting that 15d-PGJ 2 acts independently of peroxisome proliferator-activated receptor γ activation and that the α,β-unsaturated carbonyl group in the cyclopentenone ring of 15d-PGJ 2 is a requisite for the observed effects. Received 14 July 2008; received after revision 2 September 2008; accepted 12 September 2008  相似文献   
50.
Comparative analysis of proteomes using 5-fluorouracil (5-FU)-resistant human colon cancer cell line revealed that decreased galectin-3 expression was significantly associated with retarded proliferation. However, in the presence of 5-FU proliferation rate of cells with suppressed galectin-3 expression did not differ from that of cells with normal galectin-3 expression, even galectin-3 suppression augmented apoptosis. Mechanism by which galectin-3 regulates cancer cell proliferation has been identified in immunoprecipitates of the anti-galectin-3 antibody. Heterogeneous nuclear ribonucleoprotein Q (hnRNP Q) was identified as a protein interacting with galectin-3. Interestingly, while galectin-3 protein was not affected by the hnRNP Q level, its suppression was accompanied by a decrease in hnRNP Q expression. The present study demonstrates that galectin-3 stabilizes hnRNP Q via complex formation, and reduction in the hnRNP Q level leads to slow proliferation and less susceptibility to 5-FU. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. B.C.Yoo; S-H.Hong; These two authors contributed equally to this work. Received 10 September 2008; received after revision 19 October 2008; accepted 07 November 2008  相似文献   
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