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1.
Stem cell therapies for atherosclerotic diseases are promising, but benefits remain modest with present cell delivery devices in part due to cell washout and immune attack. Many stem cell effects are believed mediated by paracrine factors (PFs) secreted by the stem cells which potentiate tissue repair via activation and enhancement of intrinsic host repair mechanisms We therefore sought to create an “intravascular paracrine factor factory” by harnessing stem cells on a stent using a nanofiber (NF) stent sleeve, and thus providing a sheltered milieu for cells to continuously produce PFs on-stent. The NF sleeve acts as a substrate on which stem cells grow, and as a semi-permeable barrier that protects cells from washout and host immune response while allowing free outward passage of PFs. NF stent sleeves were created by covering stents with electrospun poly-lactic-co-glycolic acid nanofibers and were then uniformly coated with mesenchymal stem cells (MSCs). NF sleeves blocked cell passage but did not hamper MSC attachment or proliferation, and did not alter MSC morphology or surface markers. NF sleeve MSCs continued to secrete PFs that were biologically active and successfully induced tubulogenesis in human endothelial cells. NF stent sleeves seeded with allogeneic MSCs implanted in pigs remained patent at 7 days without thrombotic occlusion or immune rejection. Our results demonstrate the feasibility of creating an intravascular PF factory using a stem cell impregnated NF stent sleeve, and pave the way for animal studies to assess the efficacy of local PF production to treat ischemic artery disease.  相似文献   
2.
目的 探讨 CD73 对大鼠心肌细胞(CMs)增殖和功能的影响。 方法 体外培养原代大鼠 CMs 和大鼠心肌细胞系 H9C2,构建慢病毒 CD73 过表达载体和空载病毒组,分别转染 CMs 和 H9C2。实验分组:CD73 过表达组(OE组)和阴性对照组(NC组),即CMs-OE组和CMs-NC组;H9C2-OE组和H9C2-NC组,每组各5只。Real-time PCR 法检测转染病毒后各组细胞 CD73 基因水平表达情况;MTT 法检测细胞增殖能力变化;无损伤心肌细胞功能分析仪检测 CMs 细胞增殖曲线、倍增时间和搏动变化。 结果 慢病毒转染 CMs 和 H9C2 72 h 后,过表达组 CD73 mRNA 水平明显高于对照组(P<0.05);CMs和 H9C2 转染后3~4 d的增殖能力为OE组大于NC组(P<0.05);CMs 和 H9C2 细胞增殖曲线均显示 OE 组高于 NC 组,CMs 和 H9C2 倍增时间为 OE 组低于 NC 组(P<0.05);CMs转染后72 h显示OE组细胞搏动率高于NC组, OE组转录因子T-同源盒基因5(TBX5)表达和血管内皮生长因子(VEGF)的分泌高于NC组,而缺氧诱导因子1α(HIF-1α)及肝病坏死因子α(TNF-α)的分泌低于NC组。 结论 CD73可促进 CMs 和 H9C2 的增殖,促进 CMs 搏动及TBX5表达和VEGF分泌,抑制HIF-α和TNF-α的分泌。  相似文献   
3.
目的 以网络药理学技术探讨趋化因子-13(CXCL-13)对人骨髓间充质干细胞(BMSCs)增殖和迁移的影响。 方法 在线数据库预测CXCL-13作用于BMSCs的靶点。Metascape数据库对靶点的基因本体论和京都基因与基因组百科全书(KEGG)信号通路进行富集分析。STRING 11.0数据库进行蛋白质相互作用分析,Cytoscape 3.8的cytoHubba 0.1插件筛选核心基因编码的蛋白质。BMSCs分为对照组、CXCL-13组和PI3K抑制剂组。分别以MTT、流式细胞术和Transwell细胞小室迁移实验检测各组BMSCs的吸光度(A)值、细胞凋亡率和细胞迁移数目情况;ELISA检测各组BMSCs上清液表皮生长因子(EGF)和血管内皮生长因子(VEGF)蛋白含量。Western blotting检测各组BMSCs的Akt、磷酸化Akt(p-Akt)蛋白的表达。 结果 CXCL-13作用于BMSCs 21个靶点。与细胞增殖相关的生物学过程包括干细胞增殖、调节内皮细胞增殖、正向调控平滑肌细胞增殖等32条;与细胞迁移相关的生物学过程包括调节细胞迁移、阿米巴状细胞迁移、调节内皮细胞迁移等22条。KEGG通路包括癌症途径、PI3K-Akt信号通路、MAPK信号通路等40条。核心蛋白包括肿瘤蛋白P53(TP53)、表皮生长因子受体(EGFR)、90kD热休克蛋白αB1(HSP90AB1)、蛋白激酶Cα(PRKCA)、雌激素受体2(ESR2)及前列腺素E受体4(PTGER4)。与其他组相比,CXCL-13组BMSCs的吸光度(A)值和细胞迁移数目均显著增高(P<0.01,n=15),细胞凋亡率明显降低(P<0.01,n=15);PI3K抑制剂组BMSCs的A值、细胞凋亡率和细胞迁移数目与CXCL-13组相比均呈相反变化(P<0.01,n=15)。相对于对照组,CXCL-13组BMSCs的EGF和VEGF蛋白含量显著提高(P<0.01,n=15),Akt和p-Akt相对表达均明显升高(P<0.01,n=9);而PI3K抑制剂组EGF和VEGF蛋白含量、Akt和p-Akt相对表达呈相反变化。 结论 CXCL-13激活PI3K-Akt通路促进BMSCs旁分泌EGF和VEGF蛋白,提高BMSCs增殖和迁移,抑制BMSCs凋亡。  相似文献   
4.
Despite extensive researches in acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), current pharmacological therapies and respiratory support are still the main methods to treat patients with ALI and ARDS and the effects remain limited. Hence, innovative therapies are needed to decrease the morbidity and mortality. Because of the proven therapeutic effects in other fields, mesenchymal stem cells (MSCs) might be considered as a promising alternative to treat ALI and ARDS. Numerous documents demonstrate that MSCs can exert multiple functions, such as engraftment, differentiation and immunoregulation, but now the key researches are concentrated on paracrine factors secreted by MSCs that can mediate endothelial and epithelial permeability, increase alveolar fluid clearance and other potential mechanisms. This review aimed to review the current researches in terms of the effects of MSCs on ALI and ARDS and to analyse these paracrine factors, as well as to predict the potential directions and challenges of the application in this field.  相似文献   
5.
肝纤维化是肝脏对慢性炎症、坏死或其他损伤的修复反应,肝硬化则是肝纤维化的终末结局.肝纤维化、肝硬化严重影响着人类健康,但其治疗仍是尚未完全攻破的难题.目前,肝移植是比较有效的治疗手段之一.但是,受到肝源缺乏、并发症多、排异反应和价格昂贵等诸多因素的影响,致使其难以广泛开展.在少数接受了肝移植的患者中,3、12、36个月的生存率分别是94%、 88%、79%.因此,寻找一种有效的替代疗法来治疗这种危及生命的疾病具有重要意义.近年来,以干细胞为基础的细胞疗法从动物模型和临床患者身上均观察到良好的效应,现就肝细胞、肝星状细胞(hepatic stellate cells,HSCs)、旁分泌机制在间充质干细胞(mesenchymal stem cells,MSCs)治疗肝纤维化中的作用机制及其临床应用前景等方面进行综述.  相似文献   
6.
7.
A local melanocortin system is active during tissue injury and inflammation. Thus far this system has been described as autocrine in nature where local production of pro-opiomelanocortin (POMC) peptides by leukocytes feeds back on melanocortin receptor (MC-R) expressing immune cells to quell inflammatory cytokine production. Here we present evidence that POMC peptides may generate extracellular matrix (ECM) changes by inducing matrix production by cells of the mesenchymal lineage through activation of the MC2-R. Using immunoblot, we determined that mouse aorta-derived mesenchymal progenitor cells express both MC2-R and MC3-R. These progenitors respond to treatment with ACTH by increasing collagen matrix synthesis as assessed by picrosirius red stain and (3)H-proline incorporation. ACTH also induces transient increases in intracellular calcium ([Ca(2+)](i)) as assessed using the fluorescent Ca(2+) indicator, fura-2. The ACTH-induced changes in [Ca(2+)](i) are consistent with MC2-R signaling and consist of both an intracellular release and an extracellular influx of Ca(2+). Both mouse aortic mesenchymal progenitors and mouse macrophage cells express POMC and the prohormone convertase 1/3 (PC1/3) indicating they have the potential to contribute to the local production of POMC peptides. These data demonstrate functional MC2-R expression in mouse aorta-derived mesenchymal progenitors and implicate both macrophage and mesenchymal cells as relevant sources of local POMC peptides.  相似文献   
8.
Cardiovascular disease (CD) is a major burden for Western society. Regenerative medicine has provided encouraging results, yet it has not addressed the focal defects causing CD and mainly related to the inefficient repair programme of the heart. In this scenario, stem cells have been broadly investigated and their paracrine effect proposed as a possible working strategy to boost endogenous mechanisms of repair and regeneration from within the cardiac tissue.The scientific community is now focusing on identifying the most effective stem cell secretome, as the whole of bioactive factors and extracellular vesicles secreted by stem cells and endowed with regenerative potential. Indeed, the adult stem cell-paracrine potential for cardiac regeneration have been widely analyzed with positive outcome. Nevertheless, low yield, invasive sampling and controversial self-renewal may limit adult stem cell application. On the contrary, fetal and perinatal stem cells, which can be easily isolated from leftover sample via prenatal screening during gestation or as clinical waste material after birth, can offer an ideal alternative. These broadly multipotent immature progenitors share features with both adult and embryonic stem cells, show high self-renewal, but they are not tumorigenic neither cause any ethical concern. While fetal and perinatal stem cells demonstrated to improve cardiac function when injected in the injured heart, the comprehensive characterization of their secretome for future applications is still at its infancy.In this review, we will discuss the paracrine potential of the fetal and perinatal stem cell secretome to provide cardiac repair and resurge the dormant mechanisms of cardiac regeneration for future therapy.  相似文献   
9.
支气管肺发育不良( bronchopulmonary dysplasia,BPD)常见于早产儿。20世纪80年代以来随着医疗技术的提高,早产儿成活率逐渐升高,同时BPD发病率也逐渐增加。目前,BPD的常规治疗并不理想,故亟需寻求一种新创性疗法减轻BPD造成的呼吸系统损伤,提高生活质量。近年来,间充质干细胞( mesenchymal stem cell,MSC)的研究为BPD的治疗提供了新切入点。该文就MSC治疗BPD的可能作用机制及目前研究现状进行了初步探讨。  相似文献   
10.

Background

Whether combined transplantation of mesenchymal stem cells (MSCs) and endothelial progenitor cells (EPCs) is more effective than transplantation of a single cell type in the restoration of erectile function is unknown.

Aim

To investigate the effect of combined transplantation of MSCs and EPCs on restoration of erectile function in rats with cavernous nerve injury (CNI).

Methods

MSCs were isolated from human bone marrow and EPCs were isolated from human umbilical cord blood. MSCs and EPCs were identified by flow cytometry and in vitro differentiation or immunofluorescence staining. 25 8-week-old male Sprague-Dawley rats were allocated to 1 of 5 groups: sham operation group, bilateral CNI group receiving periprostatic implantation of MSCs plus EPCs, MSCs, EPCs, or phosphate buffered saline (control group). 2 weeks after CNI and treatment, erectile function of rats was measured by electrically stimulating the CN. The penis and major pelvic ganglia were harvested for histologic examinations. RNA and protein levels of neurotrophin factors (vascular endothelial growth factor, nerve growth factor, and brain-derived neurotrophic factor) in mono- or coculture MSCs and EPCs were assessed by real-time polymerase chain reaction and enzyme-linked immunosorbent assay, respectively.

Outcomes

Intracavernous pressure and mean arterial pressure were measured to evaluate erectile function. Histologic examinations of the penis and major pelvic ganglia and RNA and protein levels of neurotrophin factors in MSCs and EPCs were performed.

Results

MSCs and EPCs expressed the specified cell markers and exhibited the typical appearance and characteristics. Treatments using MSCs and/or EPCs could increase endothelial and smooth muscle contents of the corpus cavernosum, decrease caspase-3 expression and increase penile neuronal nitric oxide synthase expression, and restore the neural component of the major pelvic ganglia in rats with CNI. Combined transplantation of MSCs and EPCs had a better effect on improving erectile function than single transplantation of MSCs or EPCs. Expression levels of vascular endothelial growth factor and nerve growth factor in coculture MSCs and EPCs were significantly higher than those of primary MSCs or EPCs.

Clinical Translation

Combined transplantation of MSCs and EPCs was more effective in restoring erectile function in CNI-related erectile dysfunction models.

Strengths and Limitations

The study, for the 1st time, proved that combined transplantation of MSCs and EPCs was more effective in restoring erectile function in rats with CNI. The rat model might not represent the human condition.

Conclusion

Combined periprostatic transplantation of MSCs and EPCs could restore erectile function in rats with CNI more effectively. MSCs might restore CN fibers by secreting neurotrophin factors such as vascular endothelial growth factor and nerve growth factor, and EPCs could enhance the paracrine activity of MSCs.Fang J-f, Huang X-n, Han X-y, et al. Combined Transplantation of Mesenchymal Stem Cells and Endothelial Progenitor Cells Restores Cavernous Nerve Injury-Related Erectile Dysfunction. J Sex Med 2018;15:284–295.  相似文献   
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