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111.
AIM:To understand the relationship between pentanucleotide repeat(PNR) polymorphism of the apolipoprotein(a) gene and lipoprotein natures of normal Han population. METHODS:The serum levels of TG, TC, LDL-C,HDL-C, apo AI, apo B and Lp(a) were measured and the polymorphism of the apo(a) PNR was studied by using PCR-SSCP in 153 random normal individuals in Hubei Han population respectively. RESULTS:The relative frequencies of apo(a) PNR allele were significantly different from western population. The apo(a) gene which copy number of PNR is 5 was associated with high Lp(a) levels. No marked differences in the levels of TG, TC,LDL-C, HDL-C, apo AI and apo B were found among the various genotype groups of apo(a) PNR in Hubei Han. CONCLUSION:The data of lipids and PNR polymorphism of the apo(a) gene from healthy Hubei Han were obtained. The apo(a) allele with 5(TTTTA)-repeats may be related to high serum Lp(a) levels in the Hubei Han population. 相似文献
112.
AIM: To investigate the plasma neurotensin(NT) concentration in patients with coronary heart disease: acute myocardial infarction(AMI),unstable angina(UA),stable angina pectoris(SAP), old myocardial infarction (OMI), and to study the relationship between the plasma NT level and the myocardial ischemia . METHODS:The plasma NT concentration of 30 patients with AMI,32 pat ients with UA,35 patients with SAP,31 pat ients with OMI and 32 normal controls were determined by radioimmunoassay(RIA). RESULTS: The plasma NT level in patients with AMI(24 h),in patients with UA when angina attacked is significantly higher than that of healthy controls. The plasma NT level in patients with SAP, in patients with OMI is not significantly different from that of healthy controls. The NT level of patients with UA when angina attacked is significantly higher than that after 2 weeks treatment (P<0.01). The NT level of AMI patients rose from early period and reached peak value at 24 h .It began to decline at 48h,and restored to normal level at 72h. CONCLUSION: When acute myocardial ischemia occured in patients with coronary heart disease, the plasma NT level was elevated. This suggests NT may have participated in the pathophysiological course of myocardial ischemia. 相似文献
113.
AIM:To approach the relationship between the expression of intercellular adhesion (ICAM-1 mRNA) and acute lung injury (ALI) as well as the mechanisms of rhubarb in the prevention and treatment of the lung injury. METHODS:ALI animal model was performed by Lipopolysaccharide (LPS). The rats were divided into 4 groups: LPS group, control group, rhubarb+LPS group and dexamethasone+LPS group. Histopathological examination and biological markers were measured for the lung specimens. Molecular hybridization method was used to determine the expression of ICAM-1 mRNA. RESULTS:The ICAM-1 mRNA expression in the lung tissues of LPS group significantly increased compared with control group (P<0.01), rhubarb and dexamethasone had the action of decreasing the ICAM-1 mRNA expression (P<0.05, P<0.01); pathologic changes and the biological markers of ALI significantly decreased or ameliorated. CONCLUSION:The increase in the expression of ICAM-1 mRNA in the lung tissues of ALI is involved in the formation of ALI. Rhubarb and dexamethasone can ameliorate the lung damage, mechanism of which may be related to the inhibition of ICAM-1 mRNA expression. 相似文献
114.
AIM: To study the relationship between nitric oxide (NO) and gastric mucosal injury induced by reserpine in rats. METHODS: Sixteen healthy male Wistar rats were randomly divided into control group and experimental group (n=8). NO contents and malondialdehyde(MDA) contents in plasma, gastric mucosa of the rats were respectively determined with Cadmium-reduct plus Greiss and TBA; nitric oxide synthase in gastric walls of the rats were observed using NADPH-diaphorase histochemistry and quantitatively measured with image analyzer. RESULTS: The NO contents in both plasma and gastric mucosa of experimental group were significantly lower than that in control group (P<0.01),but their MDA contents were both higher than that in control group(P<0.05,P<0.01);the densities and A values of nitric oxide synthase (NOS)-positive nerve-cells and nerve fibers in gastric walls of experimental group were all obviously lower than that in control group (P<0.05,P<0.01). CONCLUSION: The mechanism of the reserpine-induced gastric mucosal injury in rats might be related to NO insufficiency arisen from the inhibition of NOS activity in NANC nerves in gastric wall,which might weaken the protection to gastric mucosa. 相似文献
115.
AIM: To detect the effect of intercellular adhesion molecule-1(ICAM-1) monoclonal antibody on microcirculation disorder in burn shock of Wistar rats. METHODS: The blood flow velocity and diameter of venule were measured with RBC tracking correlator and IV550 model video microscaler in burn shock models of rats. The number of leukocytes adhered on venule wall was calculated under microscope. The animal survival time was observed. RESULTS: ICAM-1monoclonal antibody could attenuate the falling of mean arterial pressure, significantly reduce the number of leukocytes adhered on venule wall, and obviously prolong the animal mean survival time, but less than 24h.CONCLUSION: ICAM-1 monoclonal antibody can decrease the number of adhered leukocytes to endothelial cells, attenuate the tether of leukocytes to venule and improve microcirculation and protect tissue cells in burn shock of rats. However, a comprehensive therapy should be taken in severe shock. 相似文献
116.
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
117.
NIE Xiao-min LIU Rui-run HUANG Zhen-wen DONG Jian-zeng ZHANG Jin-ying LI Geng-shan 《园艺学报》2001,17(3):248-250
AIM:To investigate the effect of L-arginine (L-Arg) on intimal proliferation and expression of related cell cycle regulatory factors after vascular injury in rats. METHODS:Rats were divided into three groups :sham operation group, balloon injury group(this group included balloon 48 h,7 d and 14 d subgroup) and balloon+L-Arg group. Neointima area were calculated morphologiocally. The expression of cyclin dependent kinase-2(CDK2),cyclin E and proliferation cell nuclear antigen (PCNA) were measured by means of immunohistochemical technique and computer image analyzer. RESULTS:After vascular balloon injury, the level of plasma NO decreased, CDK2、cyclin E and PCNA expressed in the media at 48 h and in the neointima at 7 d and 14 d but with low and undetected expression in the media, the expression of CDK2, cyclin E and PCNA increased with the intima thickening. Compared with balloon 14 d group, the plasma NO level increased (P<0.01), the neointima area reduced by 59.1%(P<0.01) and the positive expression indexes of CDK2, cyclin E and PCNA decreased by 36.1%, 46.3% and 76.2% respectively in balloon+L-Arg group (P all<0.01). CONCLUSION:L-Arg can effectively repress intima proliferation after vascular injury, which may be associated with its inhibiting the proliferation of vascular smooth muscle cell through downregulating the excessive expression of CDK2, cyclin E and PCNA. 相似文献
119.
The effect of tri-o-cresyl phosphate (TOCP) and methamidophos (MET) on potassium-stimulated 45Ca uptake by brain synaptosomes in hens was studied. An in vivo test showed that TOCP increased potassium-stimulated calcium uptake 2 h after its administration, but that verapamil suppressed the enhancement of this calcium uptake. An in vitro test showed that lower concentrations of TOCP stimulated calcium uptake by synaptosomes, but that higher concentrations inhibited the uptake. In contrast, all tested concentrations of MET obviously inhibited calcium uptake; however, since calcium uptake was decreased by the administration of verapamil plus either TOCP or MET, the mechanism by which TOCP affects the voltage-operated calcium channel may be different from that of MET. The disruption of calcium homeostasis may be involved in organophosphate-induced delayed neurotoxicity (OPIDN). Calcium channel blocker may ameliorate OPIDN by maintaining calcium homeostasis in nerve cells. 相似文献
120.
AIM:This study was designed to investigate the effects of sodium restriction and sodium supplementation on the expression of angiotensinogen mRNA in myocardium of rats with congestive heart failure(CHF).METHODS:Radioimmunassay and in situ hybridization techniques were used to determine the angiotensin Ⅱ(AngⅡ)contents and the expression of angiotensinogen(ANG)mRNA in myocardium, respectively.RESULTS: In sodium restricted group, the plasma sodium was obviously lower than that in CHF group(P<0.05), while the contents of AngⅡ,the expression of ANG mRNA in myocardium and the ratio of heart weight/body weight(HW/BW)were significantly higher than those in CHF group (P<0.05 or P<0.01). It was also found that the AngⅡ, the mRNA contents in rat myocardium and the ratio of HW/BW were not significantly changed in case of sodium supplementation. CONCLUSION:Restriction of sodium intake can further activate the local renin-angiotensin system in CHF heart. 相似文献