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71.
Objectives To investigate the effect of advanced glycosylation end products (AGEs) on the a ctivity of protein kinase C (PKC) in human peripheral blood mononuclear cells (P BMC) and to observe whether aminoguanidine (AG) can influence the effect of AGEs .Methods After PBMC were isolated from human peripheral blood and incubated with differen t concentrations of AGEs-BSA for various periods, total PKC activity in PBMC wa s determined by measuring the incorporation of (32)P from [γ-(32) P] ATP into a special substrate using Promega PKC assay kit.Results AGEs-BSA increased the total PKC activity in PBMC from 83.43±6.57 pmol/min/ mg protein to 116.8±13.82 pmol/min/mg protein with a peak at 15 min. AGEs -BSA also increased the total PKC activity in a concentration-dependent manner fro m 83.1±6.4 pmol/min/mg protein (control) to 119.1±13.3 pmol/min/mg prote in (control vs AGEs-BSA 400 mg/L, P<0.01).Furthermore, AGEs-BSA induc ed an elevation of PKC activity in a glycosylating time-related manner, from 80 .9±8.2 (control) to 118.3±11.5 pmol/min/mg protein (glycosylation for 12 wk, P<0.01).The total PKC activity stimulated by AGEs-BSA pretreated wi th AG (100, 200 mg/L) was markedly lower than that of AGEs-BSA group not pretr eated with AG (P<0.05, P<0.01).Conclusions AGEs-BSA increased the total PKC activity in PBMC in a concentration and incuba tion time dependent manner. The ability of AGEs-BSA to stimulate PKC activity was markedly decreased by pretreatment of AGEs-BSA with AG. 相似文献
72.
止消通脉宁对糖尿病大鼠肾脏胶原非酶糖化的影响 总被引:12,自引:1,他引:11
采用STZ糖尿病大鼠模型 ,在 6 ,12周分别观察肾脏组织发生非酶糖基化的情况 ,并观察止消通脉宁及氨基胍的作用。结果发现不同病程STZ糖尿病大鼠肾脏组织的胶原含量和非酶糖基化早期产物 (5 HMF)及胶原相联荧光值均明显高于正常对照组 ,并随病程的延长而增高。止消通脉宁有阻断肾脏组织非酶糖基化的作用 ,而对 5 HMF的作用优于氨基胍。说明高糖环境下肾脏组织可发生非酶糖基化 ,止消通脉宁有抑制肾脏组织非酶糖基化的作用 ,是其防治糖尿病肾病的作用机理之一 相似文献
73.
Z. Lajtman D. Nosso Z. Romic K. Trutin-Ostovic D. Krpan 《European archives of oto-rhino-laryngology》1994,251(3):170-172
Blood selenium concentrations in 43 patients with laryngeal cancer and 47 normal subjects were determined by atomic absorption spectrophotometry. No significant differences in selenium values were observed in sera from the cancer patients when compared with controls, but there were significant differences between patients with advanced (T4) supraglottic cancers and the normal controls. These results suggest that lower blood selenium levels in this latter group of laryngeal cancer patients may be a consequence of their disease rather than its cause. 相似文献
74.
PreliminaryevaluationofpelvicvascularbedisolationchemotherapyinthetreatmentofadvancedcervicalcarcinomaJiangSenandPostgraduate... 相似文献
75.
目的:分析2型糖尿病患者非酶促糖化低密度脂蛋白形成与血糖和血脂的关系,以及对胆固醇代谢的影响。方法:随机选择52例2型糖尿病患者和17例非糖尿病患者对照,测定其空腹血中血糖、血清甘油三酯、总胆固醇、低密度脂蛋白胆固醇、β脂蛋白浓度以及糖化低密度脂蛋白指数。结果:糖化低密度脂蛋白指数与血糖、血清甘油三酯、β脂蛋白、总胆固醇以及低密度脂蛋白胆固醇均呈线性正相关,其相关系数分别为r=0.870(P<0.05),r=0.938(P<0.05),r=0.92(P<0.01),r=0.993(P<0.05)和r=0.999(P<0.0005)。结论:高血糖和高甘油三酯血症可促使低密度脂蛋白高糖化形成,进而可干扰胆固醇代谢,导致低密度脂蛋白胆固醇以及总胆固醇浓度升高。 相似文献
76.
目的 研究汉族人足趾端纹理各型的分布及足趾、掌皮纹嵴线是否存在男女性别间的差异。方法 采用油墨、印泥印迹、肉眼直观并记录等方法对 32 0名汉族男女大学生的足纹进行收集、观察和分析。结果 趾端弓形纹的出现率为男生 (2 7 0 6 % )高于女生 (2 3 2 5 % ) ,而趾端总嵴线均数亦为男生 (10 9 2 6± 1 2 0 6 )高于女生 (92 5 3± 1 0 6 2 ) ,这表明男生的真实花纹的花样大于女生。男女生足趾、掌各区总嵴线数经t检验 ,P >0 0 5。结论 足纹各区总嵴线数虽在男女之间存在一定的差异 ,但差异均无显著意义 相似文献
77.
多普勒超声心动图评估左心室舒张末压的研究 总被引:1,自引:0,他引:1
目的探讨多普勒超声心动图评估左室舒张末压的有效方法与指标。方法对68例病人采用左心导管测压及经胸多普勒超声心动图检测。结果对比研究显示,联合肺静脉与二尖瓣血流频谱分析优于二尖瓣血流频谱分析,肺静脉A峰和二尖瓣A峰时限差值(PAd-Ad)与左室舒张末压实测值呈最佳相关性(r=0.72,P<0.01)。结论认为应用多普勒超声心动图测定PAd与Ad,并以其差值估测左室舒张末压,是一项简便、可靠的无创性评估左室舒张末压的方法。PAd-Ad≥0可作为临床判断左室舒张末压增高[≥2.0kPa(15mmHg)]的一项半定量指标。 相似文献
78.
The mammary gland is a hormone-target organ derived from epidermis and develops as a result of reciprocal mesenchymal-epithelial interactions. The induction of mammary differentiation from indifferent epidermal cells by mammary mesenchyme implies induction of the complement of hormone receptors characteristic of normal mammary epithelium in cells of the epidermis. Considering the facts that mammary epithelial differentiation is induced by mammary mesenchyme and that certain aspects of hormone response (androgen-induced mammary regression) are inextricably linked to mesenchymal-epithelial interactions, it is evident that the biology of the mammary gland arises from and is maintained via cell-cell interactions. As a corollary, perturbation of stromal-epithelial interactions in adulthood may play a role in mammary carcinogenesis and in turn may provide opportunities for differentiation therapy. 相似文献
79.
I Rzepka-Górska A Chudecka-Glaz M Kosmider J Malecha 《International journal of gynaecology and obstetrics》2003,81(2):199-205
OBJECTIVES: Lowering gonadotropin levels with gonadotropin-releasing hormone (GnRH) analogues in patients with ovarian cancer remains open to debate. The aim of this study was to assess the results of treatment in stage III and stage IV ovarian cancer patients who had surgery supplemented with chemotherapy, radiotherapy, and GnRH analogues. Gonadotropin levels were monitored during treatment. METHODS: The study group comprised 69 patients aged 27-70 years, stratified according to the type of treatment. The overall disease-free, 5-year survival rates and the frequency of remissions were analyzed. Hormonal tests [follicle-stimulating hormone (FSH) and luteinizing hormone (LH)] were performed in 58 patients. Associations were checked between gonadotropin levels, clinical findings, and survival. The results were statistically compared. RESULTS: Statistically significant differences were noted when chemotherapy was supplemented with GnRH analogues and/or radiotherapy. Administration of GnRH analogues resulted in significantly lower levels of LH than of FSH. Levels of FSH were significantly lower in patients surviving at least 5 years or in complete remission at the time of this study. CONCLUSIONS: Combined therapy can produce favorable results in late-stage ovarian cancer, and GnRH analogues have an important role in treatment strategy. 相似文献
80.
FOLFOX方案治疗30例晚期胃癌疗效观察 总被引:22,自引:1,他引:22
目的:观察每二周高剂量亚叶酸钙(CF)/氟脲嘧啶(5-FU)与草酸铂(L-OHP)方案(FOLFOX方案)治疗晚期胃癌的临床疗效和毒副反应。方法:采用高剂量CF/5-FU/L-OHP深静脉输注方案(CF200mg.m^2-1.d^-1,静滴2小时,第1、2天;5-FU400mg.m^2-1.d^-1,静推,第1天,5-FU1600mg.m^2-1.d^-1,静滴22小时,第1、2天;L-OHP130mg.m^2-1.d^-1,静脉输注4小时,第1天),化疗方案以14天为1周期,重复4周期后间隔1个月评定疗效。结果:全组30例,总有效率为53.3%,18例初治组的有效率为61.11%,其中CR1例。12例复治组的有效率为41.7%,初治组中位缓解期为5个月。复治组的中位缓解期为3个月。Ⅱ、Ⅲ度口腔炎发生率为26.7%,7例出现手足综合征,血液学毒性轻微。结论:每二周高剂量CF/5-FU/L-OHP方案是治疗晚期胃癌有效安全的化疗方案。 相似文献