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981.
目的 :考察重组人白细胞介素 10 (rhIL 10 )对可溶性鸡Ⅱ型胶原 (SCCⅡ )治疗大鼠佐剂性关节炎(AA)疗效的影响。方法 :通过测量足肿胀度、体重、胸腺与脾脏系数 ,观察不同部位淋巴细胞ConA增殖反应并检测腹腔巨噬细胞 (PMΦ)与滑膜组织细胞(SMCs)产生IL 1的水平。结果 :与SCCⅡ(0 .0 3mg·kg-1·d-1,ig)或IL 10 (1,2 μg·d-1,sc)单独治疗比较 ,二者联合治疗大鼠AA ,明显改善上述观察指标 ,同时使SCCⅡ的口服耐受诱导期缩短 ,增强了治疗效果。结论 :IL 10能提高SCCⅡ治疗大鼠AA的治疗效果。 相似文献
982.
国产重组人粒细胞集落刺激因子在妇科恶性肿瘤化疗中的应用 总被引:2,自引:0,他引:2
目的:探讨不同剂量国产重组人粒细胞集落刺激因子(rhG-CSF)在妇科恶性肿瘤化疗中的疗效,并与进口rhG-CSF比较。方法:98例卵巢癌、宫体癌和宫颈癌患者随机分成3组,分别按75μg·d-1和150μg·d-1剂量皮下注射国产rhG-CSF和进口75μg·d-1 rhG-CSF,直到白细胞或中性粒细胞绝对数升至正常水平以上。结果:不同剂量国产或进口rhG-CSF均能使3组患者血WBC和ANC水平在用药d 4后升至正常水平以上;在初次化疗时,用不同剂量(75μg和150μ)国产和进口(75μg)rhG-CSF升WBC至正常水平的天数无显著差异(P>0.05),但重复化疗期间150μg国产,rhG-CSF升白细胞的疗效显著优于75μg国产或进口rhG-CSF;同等剂量国产rhG-CSF与进口rhG-CSF升WBC效果一致。结论:75μg小剂量国产rhG-CSF在妇科恶性肿瘤初期化疗中升WBC的疗效肯定,重复化疗时较大剂量(150μg)rhG-CSF升WBC的效果优于小剂量rhG-CSF。同等剂量国产rhG-CSF与进口rhG-CSF的疗效无明显差异。 相似文献
983.
目的:研究重组人白细胞介素10(rhIL-10)对无血清培养的角朊细胞增殖和产生细胞因子的影响,探讨其治疗银屑病的作用机制。方法:用四甲基偶氮唑蓝比色法(MTT)测定其对细胞增殖的影响;小鼠胸腺细胞增殖法检测白细胞介素1(IL-1);ELISA法检测白细胞介素6(IL-6)、白细胞介素8(IL-8)。结果:重组人白细胞介素10抑制角朊细胞增殖与IL-1、IL-6及IL-8的分泌,并呈剂量依赖关系。结论:重组人白细胞介素10抑制角朊细胞与细胞因子分泌,可能是治疗银屑病的作用机理之一. 相似文献
984.
985.
目的探讨年龄增加对人血管内皮依赖性舒张作用的影响及其初步机制。方法采用血管环张力测定法,在15例不同年龄段(51~83岁)胃癌患者手术切除的胃网膜动脉上,测定0.001~10 μmol/L乙酰胆碱(ACh)诱发的血管内皮依赖性舒张作用和内皮依赖性超级化因子(EDHF)样血管舒张作用的变化;采用实时荧光定量PCR(qRT-PCR)方法观察不同年龄人血管中的内皮型NO合酶(eNOS)、环氧合酶(COX)、胱硫醚γ裂解酶(CSE)以及C-型利钠肽(CNP)基因表达的改变。结果相同剂量下,ACh诱导出人动脉内皮依赖性的舒张作用会随着年龄的增加而减弱(P<0.05),其EDHF样血管舒张作用也明显降低(P<0.05);qRT-PCR发现随着年龄的增加,其血管eNOS、CSE和CNP mRNA表达降低(P<0.05),而COX mRNA表达的年龄趋势不明显。结论随年龄的增加,血管内皮依赖性舒张和EDHF样舒张作用降低,可能与内皮合成的NO和CNP等舒血管物质减少有关。 相似文献
986.
目的:探讨雷珠单抗联合玻璃体切割术(VT)对PDR患者血清VEGF-A、人基质细胞衍生因子1(SDF-1)表达的影响。
方法:选取2017-01/2018-01本院收治的PDR患者120例,依据随机数字表法分为A组和B组,每组60例,A组给予VT治疗,B组在此基础上给予玻璃体腔注射雷珠单抗治疗,比较两组VT手术情况、并发症及VEGF-A、SDF-1、BCVA、CMT。
结果:两组术后血清VEGF-A、SDF-1水平明显低于术前,且B组明显低于A组(P<0.05); B组VT手术时间、电凝止血、术中出血及并发症发生率明显低于A组(P<0.05); 两组术后1d, 3mo BCVA、CMT明显低于术前,且B组明显低于A组(P<0.05)。
结论:雷珠单抗联合VT可有效降低PDR患者血清VEGF-A、SDF-1水平,减少VT创伤及并发症,且可有效改善患者BCVA、CMT。 相似文献
987.
Construction of a full-thickness human corneal substitute from anterior acellular porcine corneal matrix and human corneal cells 下载免费PDF全文
AIM: To construct functional human full-thickness corneal replacements.
METHODS: Acellular porcine corneal matrix (APCM) was developed from porcine cornea by decellulariztion. The biomechanical properties of anterior-APCM (AAPCM) and posterior-APCM (PAPCM) were checked using uniaxial tensile testing. Human corneal cells were obtained by cell culture. Suspending ring was designed by deformation of an acupuncture needle. MTT cytotoxicity assay was used to check the cytotoxicity of suspending ring soaking solutions. A new three-dimensional organ culture system was established by combination of suspending ring, 48-well plate and medium together. A human full-thickness corneal substitute was constructed from human corneal cells with AAPCM in an organ coculture system. Biochemical marker expression of the construct was measured by immunofluorescent staining and morphological structures were observed using scanning electron microscopy. Pump function and biophysical properties were examined by penetrating keratoplasty and follow-up clinical observations.
RESULTS: There were no cells in the AAPCM or PAPCM, whereas collagen fibers, Bowman’s membrane, and Descemet’s membrane were retained. The biomechanical property of AAPCM was better than PAPCM. Human corneal cells grew better on the AAPCM than on the PAPCM. There was no cytotoxicity for the suspending ring soaking solutions. For the constructed full-depth human corneal replacements keratocytes scattered uniformly throughout the AAPCM and expressed vimentin. The epithelial layer was located on the surface of Bowman’s membrane and composed of three or four layers of epithelial cells expressing cytokeratin 3. One layer of endothelial cells covered the stromal surface of AAPCM, expressed Na+/K+ATPase and formed the endothelial layer. The construct was similar to normal human corneas, with many microvilli on the epithelial cell surface, stromal cells with a long shuttle shape, and zonula occludens on the interface of endothelial cells. The construct withstood surgical procedures during penetrating keratoplasty. The corneal transparency increased gradually and was almost completely restored 7d after surgery.
CONCLUSION: AAPCM is an ideal scaffold for constructing full-thickness corneal replacement, and functional human full-thickness corneal replacements are successfully constructed using AAPCM and human corneal cells. 相似文献
988.
5-aza-2’-deoxycytidine in the regulation of antioxidant enzymes in retinal endothelial cells and rat diabetic retina 下载免费PDF全文
AIM: To investigate the roles of a DNA methyltransferase (DNMT) inhibitor 5-aza-2’-deoxycytidine (5-aza-dC) in the regulation of antioxidant enzymes in diabetic retinopathy (DR) models.
METHODS: DNMTs expressions and activity, and changes of two key antioxidant enzymes in DR, MnSOD (encoded by SOD2 gene) and glutathione S-transferase theta 1 (GSTT1), were quantified in the isolated human retinal endothelial cells (HRECs) exposed to high glucose (HG) with or without 5-aza-dC treatment. The downstream exacerbating factors including vascular endothelial growth factor (VEGF), intercellular adhesion molecule 1 (ICAM-1) and matrix metalloproteinase 2 (MMP2), which are implicated in the pathogenesis of DR and closely related to oxidative stress were also analyzed. The key parameters were confirmed in the retina from streptozotocin (STZ) diabetic rats.
RESULTS: DNMTs expression and DNMT activity was induced in HRECs exposed to HG. Hyperglycemia decreased MnSOD and GSTT1 expression. 5-aza-dC administration effectively suppressed DNMTs expression and activity and reversed the MnSOD and GSTT1 expression under HG condition. VEGF, ICAM-1 and MMP2 induced by HG were also suppressed by 5-aza-dC treatment. Similar results were observed in the retina from STZ diabetic rats.
CONCLUSION: Our findings suggest that DNA methylation may serves as one of the mechanisms of antioxidant defense system disruption in DR progression. Modulation of DNA methylation using pharmaceutic means such as DNMT inhibitors could help maintain redox homeostasis and prevent further progression of DR. 相似文献
989.
Fernando Tecles Asta Tvarijonaviciute Carlos De Torre José M. Carrillo Mónica Rubio Montserrat García 《Scandinavian journal of clinical and laboratory investigation》2016,76(4):324-330
Although saliva has esterase activity, this activity has not been characterized or studied in individuals subjected to physical stress. The aim of this report was to develop and validate an automated spectrophotometric assay for total esterase activity measurement in human saliva, as well as to study the contribution of different enzymes on this activity and its behaviour under physical stress in healthy subjects. The assay used 4-nitrophenyl acetate as substrate and was precise, accurate and provided low limits of detection and quantification. Inhibition with diisopropylfluorophosphate showed that cholinesterase, carboxylesterase and cholesterol esterase contributions not represented more than 20% of total esterase. Addition of standards of lipase and albumin to saliva samples showed that both proteins significantly contributed to esterase activity only when equal or higher than 11.6?IU/L and 250?μg/mL, respectively. Western blot analyses showed absence of paraoxonase-1 and high amount of carbonic anhydrase-VI. The high affinity of purified carbonic anhydrase-VI for the substrate supported a major contribution of this enzyme. Total esterase activity and alpha-amylase was measured in saliva samples from 12 healthy male students before and after participation in an indoor football match. The activity significantly increased after match and positively correlated with salivary alpha-amylase. This method could be used as a biomarker of physical stress in humans, with carbonic anhydrase-VI being the esterase that contributed more to the activity of the assay. 相似文献
990.
Ronald Allen Coss Christopher W. Storck Tiffany C. Wells Kari A. Kulp Miriam Wahl Dennis B. Leeper 《International journal of hyperthermia》2014,30(1):75-78
Purpose: This study tested the ability of lonidamine (LND), a clinically applicable inhibitor of monocarboxylate transporters (MCT), to thermally sensitise human melanoma cells cultured at a tumour-like extracellular pH (pHe) 6.7.Materials and methods: Human melanoma DB-1 cells cultured at pHe 6.7 and pHe 7.3 were exposed to 150?µM LND for 3?h, beginning 1?h prior to heating at 42?°C (2?h). Intracellular pH (pHi) was determined using 2′,7′-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein (BCECF) and whole spectrum analysis. Levels of heat shock proteins (HSPs) were determined by immunoblot analysis. Cell survival was determined by colony formation.Results: Treatment with LND at pHe 6.7 reduced pHi to 6.30?±?0.21, reduced thermal induction of HSPs, and sensitised cells growing at pHe 6.7 to 42?°C. When LND was combined with an acute acidification from pHe 6.7 to pHe 6.5, pHi was reduced to 6.09?±?0.26, and additional sensitisation was observed. LND had negligible effects on cells cultured at pH 7.3.Conclusions: The results show that LND can reduce pHi in human melanoma cells cultured at a tumour-like low pHe so that the 42?°C induction of HSPs are abrogated and the cells are sensitised to thermal therapy. Cells cultured at a normal tissue-like pHe 7.3 were not sensitised to 42?°C by LND. These findings support the strategy that human melanoma cells growing in an acidic environment can be sensitised to thermal therapy in vivo by exposure to an MCT inhibitor such as LND. 相似文献