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Malini Fonseka Rajesh Ramasamy Boon Chong Tan Heng Fong Seow 《Cell biology international》2012,36(9):793-801
hUCB‐MSC (human umbilical cord blood‐derived mesenchymal stem cells) offer an attractive alternative to bone marrow‐derived MSC for cell‐based therapy by being less invasive a source of biological material. We have evaluated the effect of hUCB‐MSC on the proliferation of K562 (an erythromyeloblastoid cell line) and the cytokine secretion pattern of hUCB‐MSC. Co‐culturing of hUCB‐MSC and K562 resulted in inhibition of proliferation of K562 in a dose‐dependent manner. However, the anti‐proliferative effect was reduced in transwells, suggesting the importance of direct cell‐to‐cell contact. hUCB‐MSC inhibited proliferation of K562, arresting them in the G0/G1 phase. NO (nitric oxide) was not involved in the hUCB‐MSC‐mediated tumour suppression. The presence of IL‐6 (interleukin 6) and IL‐8 were obvious in the hUCB‐MSC conditioned media, but no significant increase was found in 29 other cytokines. Th1 cytokines, IFNα (interferon α), Th2 cytokine IL‐4 and Th17 cytokine, IL‐17 were not secreted by hUCB‐MSC. There was an increase in the number of hUCB‐MSC expressing the latent membrane‐bound form of TGFβ1 co‐cultured with K562. The anti‐proliferative effect of hUCB‐MSC was due to arrest of the growth of K562 in the G0/G1 phase. The mechanisms underlying increased IL‐6 and IL‐8 secretion and LAP (latency‐associated peptide; TGFβ1) by hUCB‐MSC remains unknown. 相似文献
84.
目的:研究蝉蜕、僵蚕对大鼠系膜增生性肾小球肾炎(MsPGN)的治疗作用。方法:采用改良慢性血清病法制备的MsPGN模型,随机分为模型对照组、蝉蜕高剂量组、蝉蜕低剂量组、僵蚕高剂量组、僵蚕低剂量组,另设正常对照组。分别在用药5周、8周后检测大鼠24h尿蛋白;8周后处死大鼠,行血液生化指标检测和肾组织HE染色观察,免疫组化法检测TGF-β1的表达水平。结果:与模型对照组比较,用药5周后蝉蜕、僵蚕高剂量组显著降低大鼠24h蛋白尿(P<0.01);8周后各治疗组大鼠肾组织TGF-β1表达量,24h蛋白尿和血清胆固醇均显著下降,蝉蜕高、低剂量组血清白蛋白均有所升高,差异具有显著性意义(P<0.01)。肾组织形态学观察显示,蝉蜕、僵蚕高剂量组个别区域肾小球系膜细胞轻度增生,系膜区轻度增宽,管腔无挤压现象,较模型组明显改善。结论:蝉蜕、僵蚕均能有效降低MsPGN大鼠24h尿蛋白,改善脂质代谢,其作用机制可能与抑制TGF-β1的过度表达有关。 相似文献
85.
The complement C5b-9 complexes induced injury of glomerular mesangial cells in rats with Thy-1 nephritis by increasing nitric oxide synthesis 总被引:3,自引:0,他引:3
Thy-1 nephritis (Thy-1 N), namely, anti-Thy-1 or anti-thymocyte serum (ATS) induced nephritis (ATSN), is a typical model of human mesangioproliferative glomerulonephritis. The pathologic changes of glomerular mesangial cells (GMCs) in Thy-1 N are complement-dependent, especially C5b-9 complexes, but the role of C5b-9 in the mechanism of Thy-1 N has not been defined. Because previous studies have demonstrated that sublytic C5b-9 can increase production of several inflammatory mediators from resident glomerular cells, we utilized the isolated human membrane-bound C5b-9 complexes to stimulate the cultured rat GMCs and examined whether the GMCs can also induce the synthesis of nitric oxide (NO) in vitro. Simultaneously, the effects of antiserum against rat C5b-9 and NG-monomethyl-L-arginine (L-NMMA, NO inhibitor), including interfering with the formation of C5b-9, reducing NO production and GMCs injury were observed. The results showed that sublytic C5b-9 can increase synthesis of inducible NO from the stimulated GMCs, and that the anti-C5b-9 antiserum can obviously inhibit the pathologic changes in Thy-1 N, while L-NMMA can decrease the GMCs damage although the effect is not so significant as that of the anti-C5b-9 antiserum. These findings indicate that the synthesis of NO by GMCs can be promoted by sublytic C5b-9, and that lesions of GMCs in rats with Thy-1 N are prevented by either inhibiting C5b-9 formation or NO elevation in advance. The pathologic changes of GMCs in Thy-1 N are indeed complement C5b-9-dependent, and the glomerular injury can be mediated in part through elevation of NO from the GMCs after the sublytic C5b-9 stimulation. 相似文献
86.
Age-associated changes in stem cell populations have been implicated in age-related diseases, including cancer. However, little is known about the underlying molecular mechanisms that link aging to the modulation of adult stem cell populations. Drosophila midgut is an excellent model system for the study of stem cell renewal and aging. Here we describe an age-related increase in the number and activity of intestinal stem cells (ISCs) and progenitor cells in Drosophila midgut. We determined that oxidative stress, induced by paraquat treatment or loss of catalase function, mimicked the changes associated with aging in the midgut. Furthermore, we discovered an age-related increase in the expression of PVF2, a Drosophila homologue of human PDGF/VEGF, which was associated with and required for the age-related changes in midgut ISCs and progenitor cell populations. Taken together, our findings suggest that PDGF/VEGF may play a central role in age-related changes in ISCs and progenitor cell populations, which may contribute to aging and the development of cancer stem cells. 相似文献
87.
Adiponectin receptor ADIPOR1 activates the intracellular second messenger AMP-activated protein kinase (AMPK) that participates
in the control of the oxidative stress and apoptosis. This study reveals the presence of a functional ADIPOR1 receptor in
all the cells of the renal glomeruli. Isolated glomeruli were incubated in vitro with adiponectin and proteins analysed by
western blot. Electron microscopy using immunogold labeling was carried out on kidney sections. ADIPOR1 and catalytic AMPK
sub-units α1 and α2 were revealed in normal rat glomeruli and incubation of freshly isolated rat glomeruli with either adiponectin
or AICAR led to the activation by phosphorylation of catalytic AMPK. Electron microscopy localized with high resolution these
proteins at the plasma membrane of the three glomerular cells, namely the endothelial, the mesangial and the podocyte cells,
as well as on Bowman’s capsule epithelial cells. It is concluded that glomerular cells express a functional adiponectin receptor
ADIPOR1 which, through activation of AMPK, may play important roles in the control of oxidative stress and cell survival within
the glomerulus. 相似文献
88.
David L. Hudson 《Cytotechnology》2003,41(2-3):189-196
The prostate gland is the site of the second most common cancer in men in the UK, with 9,280 deaths recorded in 2000. Another
common disease of the prostate is benign prostatic hyperplasia and both conditions are believed to arise as a result of changes
in the balance between cell proliferation and differentiation. There are three types of prostatic epithelial cell, proliferative
basal, secretory luminal, and neuroendocrine. All three are believed to be derived from a common stem cell through differentiation
along different pathways but the mechanisms behind these processes is poorly understood. In particular, there has until recently
been very little information about prostate stem cell growth and differentiation. This review will discuss ways of distinguishing
these prostate cell types using markers, such as keratins. Methods available for the culture of prostate epithelial cells
and for the characterisation of stem cells both in monolayer and three-dimensional models are examined.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
89.
人骨髓CD34^+造血细胞体外扩增形成HPP—CFC造血祖细胞的能力 总被引:1,自引:0,他引:1
目的和方法:高增殖潜能集落形成细胞(HPPCFC)是表达CD34+DRLin-的最早期造血祖细胞之一,它在体外的增殖分化能力可反映造血干细胞的某些特征。结果:本文研究了人正常骨髓CD34+造血细胞在体外扩增和形成HPPCFC的能力。利用CIMS100免疫磁性分离术首先获得>90%的CD34+造血细胞以富集HPPCFC。在含有Epo+GMCSF+IL3+IL6+SCF(简EGIIS)的无基质液培条件下,CD34+造血细胞在四周内可持续产生单个核细胞和HPPCFC,并使其总量最高可达1770倍和8倍,以第2和3周为最佳时期,但不同个体CD34+造血细胞的这种能力差别较大。结论:高度纯化的人骨髓CD34+造血细胞能够在含有最佳组合造血生长因子的无基质液培条件下持续扩增,为临床应用提供了重要依据。 相似文献
90.