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991.
AIM: To explore the changes in serum TGF β1 in type 2 diabetes mellitus. METHODS: Forty-five cases type 2 diabetes mellitus patients were divided into three groups according to urine albumim excretion rate(UAER): normoalbuminuria(NA)group and microalbuminuria(MA) group and macroalbuminuria group (Overt DN). Serum TGF β1, fasting blood glucose(FBG), HbA1c,BUN,Cr,Ccr,lipidemia were detected in all cases. RESULTS: Serum TGF β1 in NA, MA and ODN groups was higher than that in control. Serum TGF β1 was positive correlation with Cr(r=0.390,P<0.05), LDL(r=0.503,P<0.01), HbA1c (r=0.676,P<0.01), and UARE(r=0.777,P<0.01). CONCLUSION: Type 2 diabetes mellitus have a higher serum TGF β1 than controls, serum TGF β1 was positive correlation with HbA1c and injury of renal function. 相似文献
992.
对气象因子与梨叶片水分亏缺的研究结果表明,相对湿度对梨树各类枝叶片水分亏缺均呈显著或极显著的负相关关系。通径分析证实了湿度、温度的影响,肯定了气压对短枝叶片水分亏缺的影响。多元线性逐步回归分析与通径分析的结果完全一致,梨叶片水分亏缺的日变动态和季变动态的分析结果表明,在梨的生长季节前后期注意灌水对于减少水分亏缺,提高光合强度,增加产量具有现实意义。 相似文献
993.
本文介绍在航空象片上进行树高和冠幅的量测,通过其比值以判读森林立地指数。这种方法不仅可以提高立地指数测定的工作效率,而且可以与立地制图相结合,充分地发挥航空遥感信息的潜力。 相似文献
994.
孕牛血清中早孕因子的分离纯化 总被引:2,自引:0,他引:2
采用DEAE-Sepharose(DEAE-琼脂糖凝胶)、CM-Sepharose(CM-琼脂糖凝胶)等离子交换层析、抗孕牛全血清IgG-Sepharose 4B亲和层析等技术,分离纯化妊娠4-5个月健康孕牛全血清中的早孕因子(EPF),用玫瑰花环抑制实验对各阶段产物EPF活性进行检测。结果表明,经层析过柱后的CM-ⅡA提取物有EPF活性。经SDS-PAGE银染显色证实它含有分子量为21、67、80KD的蛋白,实验结果支持21KD的多肽为主要EPF活性物成分。同时实验表明了亲和层析对进一步纯化EPF是可行的。 相似文献
995.
在短花针茅荒漠草原,利用高度一重量百分比方法确定了13种牧草的利用率。结果表明:对于大多数牧草消耗高度占总高度的50%,重量的消耗仅20%~30%;当牧草消耗高度80%时,牧草的利用率为70%。在利用率确定的情况下,可推导出各种牧草的适宜留茬高度。 相似文献
996.
WANG Hui-yan ZHANG Xiang-hong YAN Xia WANG Jun-ling SUN Xu-ming YANG Yong-bin WANG Feng-rong 《园艺学报》2001,17(2):131-133
AIM: To explore the effects of aflatoxin G1(AFG1 )on proliferation and TNF-α secretion of human peripheral blood mononuclear cells(HPBM) in vitro. METHODS: The effects of AFG1 on proliferation of HPBM were analysed with flow cytometric (FCM) DNA analysis and MTT bioassay, while that on TNF-α secretion was detected with ELISA.RESULTS: FCM analysis revealed that 6 h after treatment, proliferation index(PI) of 1000 μg/L AFG1 treated HPBM was significantly higher than that of control. 24 h after AFG1 treatment, stimulating effects on proliferation was found in HPBM treated with AFG1 at 200 μg/L and 1 000μg/L.Regression analysis showed that PI was postively correlated with the concentrations of AFG1 in the concentration range from 0 to 1 000μg/L( r=0. 5122 and 0.5119 respectively,P<0.05).MTT bioassay showed that the A value of the cells treated with AFG1 at 2 000 μg/L was higher than that of the control. Double antibody sandwich enzyme linked immunosorbent assay (ELISA) results showed that AFG1 at a dose of 100 μg/L could significantly inhibit lipopolysaccharide-induced TNF-α secretion.CONCLUSION: AFG1 could stimulate the proliferation of HPBM and could decrease TNF-α secretion at certain concentration. 相似文献
997.
HUANG Xiu-rong QI Ming-xi SHEN Shi-ren ZHENG Liang-pu LIN Jiu-ma WEI Nin 《园艺学报》2001,17(12):1196-1198
AIM: To investigate the relationship between the level of interleukin-2 (IL-2), tumour necrosis factor-α (TNF-α) and nitric oxide (NO) in aqueous humor after intraocular lens implantation. METHODS: New Zealand rabbits were divided randomly into three groups: (1) control group; (2) extracapsular cataract extraction group (ECCE); (3) extracapsular cataract extraction and posterior chamber intraocular lens implantation group (ECCE+IOL). The inflammation in all experimental rabbit eyes was observed via zoom-photo slit-lamp microscope on 1, 3, 7, 14 d and 30 d postoperation. Meanwhile, aqueous humor was drawn for white blood cell (WBC) counting and classifying and for determining IL-2, TNF-α and NO2-/NO3- contents. RESULTS: (1) The level of IL-2 and TNF-α and NO2-/ NO3- in aqueous humor of ECCE+IOL group were higher than that in ECCE and control at 1 to 14 days postoperation, respectively, it increased to peak value at 3 to 7 days postoperation and decreased gradually two weeks postoperation; (2) The changes in IL-2, TNF-α and NO2-/NO3- in each group were basically similer; (3) The changes of IL-2 and TNF-α level were closely related with NO content in aqueous humor (r=0.69, P<0.01 and r=0.98, P<0.01). CONCLUSION: IL-2, TNF-α and NO play an important role in intraocular inflammation intraocular lens implantation. 相似文献
998.
LI Qing-fen LI Zhuo-ya GONG Fei-li XU Yong JIANG Xiao-dan FENG Wei XIONG Ping 《园艺学报》2001,17(8):710-713
AIM: To compare the tumorigenecity of H22 cells transfected with TNF-α gene and its mutants(secreted TNF-α mutant, S-TNFm, transmembrane TNF-α mutant, TM-TNFm and wild type of TNF-α, Wt-TNF) in vivo. METHODS: Three kinds of mouse liver cancer cell line H22 expressing TNF-α and its two mutants were mixed with untransfected H22 at different effector/target ratio separately. The growth of tumor was examined after injection of 2.5×105(100 μL) mixed H22 tumor cells into mice. The lymphocyte infiltration in the site of tumor and the expression of Fas on tumor cells were detected by immunohistochemistry. RESULTS: The tumorigenecity of H22 cells transfected with TNF-α gene and its mutants was significantly weakened( P <0.01). Besides the cytotoxicity of the both forms of TNF, TM-TNF was found to induce the expression of death receptor Fas by tumor cells and S-TNF was shown to promote frank lymphocyte infiltration in the site of tumor. Furthermore, a transient decrease in body weight was found in mice inoculated with H22/S-TNFm. CONCLUSION: The tumorigenecity of tumor cells was reduced by transfection with TM-TNF or S-TNF gene. It results from the cytotoxicity of TNF and their activation of tumorcidal mechanisms in vivo. TM-TNF may induce tumor cell apoptosis via the Fas pathway while S-TNF may exert its antitumor effect by recruiting and activating lymphocytes in the site of tumor. 相似文献
999.
Conditioned medium prepared from the mouse fibroblast cell line L 929 which is known to produce colony-stimulating factor active on mouse bone marrow cells was also able to stimulate the growth of swine bone marrow cells in a liquid culture system. During the first 4 days of culture mononuclear phagocyte and granulocyte colonies developed. Prolonged cultured cells were classified belonging to the macrophage lineage by morphological and cytochemical criteria. These cells fulfill also functional characteristics for macrophages, like expression of Fc receptors, immune phagocytosis and production of prostaglandins. These bone marrow-derived macrophages could also be activated with LPS and lymphocyte-derived mediators. 相似文献
1000.
In a short time feeding experiment it was shown that the liver weight of cod was significantly reduced in prawn-fed cod compared to sand-eel-fed cod. The dry weight and the protein content of the muscle were not significantly reduced. It is concluded that short time energy deprivation of cod primarily affects the liver. The results futher support the view that the food type and ration of cod can produce anomalous effects in field studies of e.g. parasite induced liver weight decrease in cod. 相似文献