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1.
Obesogens are a subset of endocrine disruptor chemicals (EDCs) that cause obesity. The typical EDC 4-nonylphenol (4-NP) has been identified as an obesogen. However, the in vitro effects of 4-NP on adipogenesis remain unclear. In this study, 3T3-L1 preadipocytes and C3H/10T1/2 mesenchymal stem cells (MSCs) were used to investigate the influence of 4-NP on adipogenesis. The differentiation protocols for 3T3-L1 preadipocytes and C3H/10T1/2 MSCs took 8 and 12 days, respectively, beginning at Day 0. In differentiated 3T3-L1 preadipocytes, 20 μM 4-NP decreased cell viability on Days 4 and 8. Exposure to 4-NP inhibited triglyceride (TG) accumulation and adipogenic marker expression on Days 0–8, but the inhibitory effects were weaker on Days 2–8. The protein expression of pSTAT3 or STAT3 decreased on Days 0–8 and 2–8. Conversely, 4-NP promoted TG accumulation and the adipogenic marker expression in C3H/10T1/2 adipocytes. The opposing effects were attributed to physiological differences between the two cell lines. The 3T3-L1 preadipocytes are dependent on mitotic clonal expansion (MCE) to drive differentiation, while C3H/10T1/2MSCs and human preadipocytes are not. Additionally, 4-NP downregulated β-catenin expression in C3H/10T1/2 adipocytes. Accordingly, we hypothesized that 4-NP promotes adipogenesis. The role of the canonical Wnt pathway in the promotion of adipogenesis by 4-NP requires further validation. This study provides new insights into the mechanisms and appropriate risk management of 4-NP.  相似文献   
2.
The aim of the present study was to investigate the effect of 5‐bromo‐3,4‐dihydroxybenzaldehyde (BD) isolated from Polysiphonia morrowii on adipogenesis and differentiation of 3T3‐L1 preadipocytes into mature adipocytes and its possible mechanism of action. Levels of lipid accumulation and triglyceride were significantly lower in BD treated cells than those in untreated cells. In addition, BD treatment reduced protein expression levels of peroxisome proliferator‐activated receptor‐γ, CCAAT/enhancer‐binding proteins α, and sterol regulatory element‐binding protein 1 compared with control (no treatment). It also reduced expression levels of adiponectin, leptin, fatty acid synthase, and fatty acid binding protein 4. AMP‐activated protein kinase activation was found to be one specific mechanism involved in the effect of BD. These results demonstrate that BD possesses inhibitory effect on adipogenesis through activating AMP‐activated protein kinase signal pathway.  相似文献   
3.
Cheongchunchal (CE) is a developed crop more highly enriched in cyanidin-3-O-glucoside chloride (anthocyanin) than conventional waxy corn. Anthocyanin has been proven to have anti-oxidant, anti-inflammatory, anti-obesity, and anti-cancer effects. In this study, using high-performance liquid chromatography (HPLC), Cheongchunchal was confirmed to contain 8.99 mg/g anthocyanin. The inhibitory effect of an ethanol extract of Cheongchunchal (CE) on adipocyte differentiation was demonstrated using Oil Red O staining and a triglyceride assay. By conducting Western blotting, we also confirmed the regulatory effect of CE on adipocyte differentiation factors by assessing changes in the levels of factors that play a significant role in the differentiation of 3T3-L1 preadipocytes. A C57BL/6N mouse model of obesity was induced with a high-fat diet, and CE (400, 600, and 800 mg/kg/day) or Garcinia (245 mg/kg/day) was orally administered to verify the anti-obesity effect of CE. As a result of CE administration, the food efficiency ratio (FER), weight gain, and weight of tissues decreased. Additionally, blood biochemical changes were observed. Furthermore, the inhibitory effect of CE on adipocytes was confirmed through morphological observation and the expression of adipocyte differentiation-related factors in the liver and fat tissues. Therefore, in this study, we verified the anti-obesity effects of anthocyanin-rich CE both in vitro and in vivo.  相似文献   
4.
目的探讨人参二醇(PD)诱导3T3-L1脂肪前体细胞凋亡作用,并阐明其可能的作用机制。  相似文献   
5.
目的研究海地瓜硫酸软骨素(Acaudina Molpadioideschondroitin sulfate,AM-CHS)对3T3-L1前脂肪细胞增殖和分化的影响,并探讨其作用机制。方法采用传统的鸡尾酒诱导剂诱导分化3T3-L1前脂肪细胞,以MTT法检测AM-CHS对3T3-L1前脂肪细胞及不同分化阶段3T3-L1细胞增殖活性的影响;分别采用油红O染色和甘油三酯(triglycerides,TG)含量测定法评价其对3T3-L1前脂肪细胞分化的影响。采用RT-PCR法检测脂肪细胞中过氧化物酶体增殖体激活受体γ(peroxisome proliferators-activated receptors gamma,PPARγ)、CCAAT增强子结合蛋白α(CCAAT/enhancer bind-ing protein alpha,C/EBPα)、固醇调节元件结合蛋白-1c(ste-rol regulatory element binding protein-1c,SREBP-1c)等分化相关基因的mRNA表达水平。结果 AM-CHS能明显抑制3T3-L1前脂肪细胞和成熟脂肪细胞的增殖,抑制3T3-L1前脂肪细胞的分化过程,以对分化早期的抑制作用最强。RT-PCR结果表明,AM-CHS能明显降低脂肪细胞PPARγ、C/EBPα和SREBP-1c mRNA的表达。结论海地瓜AM-CHS能明显抑制3T3-L1前脂肪细胞的增殖和分化,其作用机制与下调分化相关基因PPARγ、C/EBPα和SREBP-1c的表达有关。  相似文献   
6.
目的研究原子力显微镜(AFM)观察甲状腺相关眼病(TAO)患者和正常眼眶前脂肪细胞膜表面的形态学异同。方法使用AFM观察TAO患者(观察组)和正常(对照组)眼眶前脂肪细胞膜表面的形态学特点。结果AFM扫描范围为80μm×80μm时2组细胞均为长梭形,细胞直径均>80μm,未观察到明显差异。扫描范围为1μm×1μm时2组细胞表面出现大小不等的颗粒状物质,观察组细胞膜表面相对粗糙,隆起结构起伏较大,排列疏密不均,其平均粗糙度为(36.480±8.146)nm;对照组细胞膜表面相对光滑,隆起结构起伏较小,排列疏密均匀,其平均粗糙度为(32.189±7.819)nm;观察组细胞膜表面粗糙度大于对照组(t=4.342,P<0.05)。结论 AFM可清楚直观地观察到眼眶前脂肪细胞膜的微观结构及三维成像情况,是一种较好的观察细胞膜表面微观形态工具。  相似文献   
7.
High fat diet induced insulin resistance correlates with dyslipidaemia and ectopic fat deposits in skeletal muscle and liver. The effects of Sutherlandia frutescens, an antidiabetic medicinal plant, on lipid metabolism were evaluated in an insulin resistant (IR) rat model and in 3 T3‐preadipocytes. Wistar rats received normal diet (ND) or high fat diet (HFD). After the onset of IR in the HFD group, the rats were subdivided into two subgroups, which either continued with HFD or were treated with 50 mg S. frutescens/kg BW/day and HFD (HFD + SF). After 4 weeks, the HFD + SF rats had a significantly lower body weight than the HFD rats (p < 0.05). Blood plasma analysis showed a decrease in insulin, free fatty acids and triglycerides. Related changes in lipid parameters were observed in the liver, skeletal muscle and adipose tissue. To investigate the effects of S. frutescens on adipose tissue, 3 T3‐L1 cells were used as a model. Treatment with S. frutescens led to a decrease in triglyceride accumulation, whilst glucose consumption and lactate production were increased (p < 0.05). These results indicate that S. frutescens directly affects mitochondrial activity and lipid biosynthesis in adipose tissue and provide a mechanism by which S. frutescens can restore insulin sensitivity by modulating fatty acid biosynthesis. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
8.
Abstract

Optimal vascularisation of the graft site is significant for improving the outcome of fat grafting. Adipose tissue, specifically the stromal vascular fraction (SVF), is known to regulate its own vascular network. In order to assess the production of angiogenetic growth factors, this study investigated the content of insulin growth factor (IGF), vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), platelet-derived growth factor (PDGF), leptin, and metallothioneine-9 (MMP-9) in the SVF after incubation in differentiation or proliferation media. The SVF was isolated from human subcutaneous adipose tissue. Cells were either cultured in proliferation medium (PM) or in differentiation medium (DM). The samples were analysed for the respective factors using ELISA after 3 and 6 days. The GF levels showed a distinctive characteristic over time depending on the culture medium. IGF, PDGF, and MMP-9 levels decreased with PM and increased with DM. VEGF levels were increased in both media. Leptin showed a decrease in both media. The differentiation medium was associated with high inter-individual distribution in growth factor production except for PDGF and Leptin. In conclusion, incubation with differentiation medium produces a more reliable increase of selected growth factors than incubation with proliferation medium. Enrichment of fat grafts with growth factor-activated autologous SVF samples could help to enable better ingrowth of the transplanted tissue and a more stable outcome. The scattering of the results could explain the inter-individual differences regarding the outcome.  相似文献   
9.
目的 构建人miR-146b慢病毒表达载体,包被病毒并检测其在人脂肪细胞中过表达效果。方法 以人基因组DNA为模板,PCR高保真扩增包含miR-146b区域上下游各100bp左右的基因组DNA,亚克隆入慢病毒表达载体,与包装质粒共转染HEK-293T细胞,包装病毒,收取病毒上清,纯化后感染人脂肪前体细胞,36 h开始观察荧光标记,72 h收取细胞,抽提RNA,Realtime PCR检测慢病毒感染下miR-146b的相应表达量。结果 成功构建人miR-146b慢病毒表达载体,包装获得的病毒感染人脂肪细胞的效率可达到85%以上,miR-146b过表达水平可接近4倍。结论 本研究成功构建了人miR-146b慢病毒表达载体,包被的慢病毒可以在人脂肪细胞中实现过表达效果,为后续功能研究奠定了基础。  相似文献   
10.
Different studies suggest that sex hormones affect adipose tissue metabolism and deposition. To investigate the possibility that androgens may play a role in adipose tissue development, we have studied androgen receptors (AR) in rat adipose precursor cells from two different anatomical fat deposits, one deep intraabdominal (epididymal) and one subcutaneous (inguinal) during the proliferation and differentiation processes. AR were quantified by [3H]R1881 specific binding in whole cells and the nuclear fraction and were localized by immunocytofluorimetry in both the cytosol and the nucleus. During the proliferative phase, total AR level decreased from D3 to D6. At confluence (D5), AR were higher in epididymal (64±4 fmol/mg protein) than in subcutaneous (33±3 fmoles/mg proteins) preadipocytes and were up-regulated by testosterone but not by 5α-dihydrotestosterone or by 17β-estradiol. At differentiation (D10-11), nuclear AR decreased by 50% in both precursor fat cell populations when compared to the confluent state (D5) and AR were no more up-regulated but rather down-regulated by testosterone. Because AR are present in preadipocytes and are differently regulated by testosterone depending on the stage of proliferation and differentiation, this study suggests that testosterone may play a role in the control of the adipogenic process.  相似文献   
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