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21.
为探讨急性缺氧对家兔左心室舒张功能、心肌细胞内钙转运和能量代谢的影响。将23只家兔分为对照组(6只)、吸入5%低氧混合气的缺氧1组(H1)(12只)、吸入10%低氧混合气的缺氧2组(H2)(5只),用心导管法测定左心室压力下降最大速率(LVdp/dtmax)和压力下降时间常数(T值);测定心肌肌浆网(SR)钙ATP酶活性、心肌SR摄钙量、心肌组织ATP和磷酸肌酸(CrP)。结果,缺氧后LVdp/dtmax下降,T值延长;缺氧组心肌SR钙ATP酶活性及摄钙量下降;心肌线粒体钙含量升高;心肌组织ATP和CrP下降,心肌组织ATP与线粒体钙含量呈负相关。提示,急性缺氧可引起左心室舒张功能障碍并影响心肌SR钙转运和心肌能量代谢。  相似文献   
22.
The parental IGROV-1 human ovarian adenocarcinoma cell line was intermittently exposed to increasing concentrations of cisplatin to obtain resistant sublines. A stable resistant subline with a resistance factor of 8.4 had been developed after 9 months and 28 passages, which was denoted IGROVCDDP. A high correlation coefficient of 0.97 was found between the log cell survival and the DNA-adduct peak level during the process of resistance development. IGROVCDDP was strongly cross-resistant to carboplatin and doxorubicin and moderately cross-resistant to etoposide, docetaxel, and topotecan. Only minor resistance against 5-fluorouracil was observed, whereas IGROVCDDP was not cross-resistant to methotrexate. Intracellular accumulation of cisplatin was 65% lower in IGROVCDDP as compared with parental IGROV-1 at 37  °C under normal conditions. Coincubation of cisplatin with the Na+/K+-ATPase inhibitor ouabain resulted in a more pronounced decrease in platinum accumulation in IGROV-1 (44% decrease) than in IGROVCDDP (26% decrease). Under energy-depleting conditions the accumulation of cisplatin in the parental cell line was approximately 60% lower than that observed under normal (energy [i.e., ATP] rich) culture conditions. In contrast, the accumulation in IGROVCDDP was not affected by ATP-depletion. There appeared to be no significant difference between the intracellular accumulation of platinum in the resistant and sensitive cells under conditions of energy deprivation or when the uptake was studied at 0  °C. In conclusion, abrogation of energy-dependent accumulation in IGROVCDDP seems to be a major mechanism of resistance to cisplatin in this cell line. Received: 21 January 1997 / Accepted: 22 July 1997  相似文献   
23.
The endogenous neurotoxin 1-methyl-6,7-dihydroxy-1,2,3, 4-tetrahydroisoquinoline (salsolinol), which is structurally similar to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), has been reported to inhibit mitochondrial complex I (NADH-Q reductase) activity as does the MPTP metabolite 1-methyl-4-phenylpyridinium ion (MPP(+)). However, the mechanism of salsolinol leading to neuronal cell death is still unknown. Thus, we correlated indices of cellular energy production and cell viability in human dopaminergic neuroblastoma SH-SY5Y cells after exposure to salsolinol and compared these results with data obtained with MPP(+). Both toxins induce time and dose-dependent decrease in cell survival with IC(50) values of 34 microM and 94 microM after 72 h for salsolinol and MPP(+), respectively. Furthermore, salsolinol and MPP(+) produce a decrease of intracellular net ATP content with IC(50) values of 62 microM and 66 microM after 48 h, respectively. In contrast to MPP(+), salsolinol does not induce an increase of intracellular net NADH content. In addition, enhancing glycolysis by adding D-glucose to the culture medium protects the cells against MPP(+) but not salsolinol induced cellular ATP depletion and cytotoxicity. These results suggest that cell death induced by salsolinol is due to impairment of cellular energy supply, caused in particular by inhibition of mitochondrial complex II (succinate-Q reductase), but not complex I.  相似文献   
24.
Research on the contribution of CRH receptor stimulation to energy homeostasis has focused on forebrain substrates. In this study, we explored the effects of caudal brainstem administration of the CRH receptor agonist, urocortin, on food intake and body weight, and on plasma glucose and corticosterone (CORT) in non-deprived rats. Urocortin (0, 0.3, 1, 3 microg) delivered, respectively, to the fourth and lateral ventricles yielded substantial suppression of food intake measured 2, 4 and 24 h later. A significant but more modest anorexia was observed between 24 and 48 h after injection. Intake responses did not differ between the injection sites, but body weight loss measured 24 h after lateral-i.c.v. injection was substantially greater than that after fourth-i.c.v. injection. Fourth-i.c.v. urocortin administration (3 microg) produced substantial elevations in plasma glucose and CORT that were not distinguishable in magnitude and duration from responses to lateral-i.c.v. delivery. Unilateral microinjection of urocortin into the dorsal vagal complex significantly reduced 24-h food intake at a dose (0.1 microg) that was subthreshold for the response to ventricular administration, suggesting that fourth-i.c.v. effects are mediated in part by stimulation of CRH receptors in this region of the caudal brainstem. The results indicate that similar effects can be obtained from stimulation of anatomically disparate populations of CRH receptors, and that interactions between forebrain and hindbrain structures should be considered in the evaluation of CRH contributions to food intake and body weight control.  相似文献   
25.
龚燕波  方崇波 《海峡药学》2008,20(11):46-48
目的 测定复方刺梨合剂中的总黄酮含量;方法 采用差示分光光度法,在392nm波长下样品不经分离直接测定;结果 线性范围5.06~50.60μg·mL-1,回归方程A=5.84×10-4+0.01321C,r=0.9996,平均回收率99.59%,RSD=1.49%.结论 所建方法 快速、简便、准确,适用于复方刺梨合剂的质量控制.  相似文献   
26.
水通道蛋白-9(AQP9)是水通道蛋白家族中特殊的一员,对水和多种中性溶质均具有转运活性.AQP9在脑内主要分布于神经胶质细胞、内皮细胞和儿茶酚胺能神经元.目前AQP9在脑内的功能还不完全清楚,初步认为除维持脑内水代谢平衡外,还可能在能量代谢方面发挥重要作用.AQP9与脑部涉及水或能量代谢的疾病如脑血管病、帕金森病和脑肿瘤等密切相关.  相似文献   
27.
新的抗癌中药枫苓合剂的主要药效学   总被引:4,自引:1,他引:4  
目的研究枫苓合剂体内抗癌作用及其他有关药理,为临床试验提供基础。方法采用对人体肿瘤移植的裸鼠体内人体胃癌MKN及人体肝癌QGY的抑制,对荷瘤和正常动物免疫功能的影响及与化学合成药合并用药等方面进行枫苓合剂的主要药效学研究。结果枫苓合剂对人体胃癌MKN 3个剂量组口服给药抑癌率分别为:74.68%-86.76%,49.86%- 59.31%及19.12%-21.68%;腹腔给药抑癌率分别为:78.72%-85.42%,55.32%-62.50%及26.69%-41.67%。对肝癌QGY口服给药抑癌率分别为:47.69%-49.33%,31.94%-33.63%及20.0%-26.0%。对荷Lewis肺癌小鼠显示提高机体NK细胞活力,有明显促进小鼠腹腔巨噬细胞的吞噬功能。对S180肉瘤的生长抑制,单独用环磷酰胺(CTX)15 mg·kg-1抑瘤率为45.16%,与枫苓合剂25 mL·kg-1合并用药抑瘤率为71.29%。结论高剂量枫苓合剂具有高的抗胃癌MKN的作用和中度的抗肝癌QGY的药效,且可提高免疫力,与CTX合用有增效作用。  相似文献   
28.
目的:提高丹参益坤口服液的质量标准。方法:采用HPLC测定丹参益坤口服液中阿魏酸的含量。结果:丹参益坤口服液中阿魏酸的含量在0.0124~0.2477μg线性关系良好,r=0.9999;平均回收率为98.77%,RSD=0.85%。结论:该方法操作易行,稳定可靠,可用于丹参益坤口服液中阿魏酸的含量,以控制该制剂的质量。  相似文献   
29.
目的:建立高效液相色谱法测定新止咳合剂中儿茶素含量的方法。方法:采用Dikma钻石C18色谱柱(4.6mm×250mm,5μm);流动相为乙睛—0.2%磷酸溶液(8∶92);检测波长为280nm,流速为1.0ml/min,柱温为35℃。结果:儿茶素进样量在0.0425~4.25μg(r=0.99999)范围内与峰面积线性关系良好,平均加样回收率为99.05%,RSD=0.72%(n=9)。结论:本法简便、快速、专属性强、重现性好;可作为新止咳合剂的质量控制方法。  相似文献   
30.
ContextQiangli Wuhu (QLWH) mixture is a concoction approved and registered by Ningxia Medical Products Administration. It has therapeutic effects on various types of pneumonia.ObjectiveTo clarify the mechanisms of QLWH in treating pneumonia.Materials and methodsThe potential targets of QLWH in the treatment of pneumonia were predicted by network pharmacology. Male, Institute of Cancer Research (ICR) mice were randomly divided into five groups of 12 mice, control, vehicle, QLWH (10 and 20 mg/kg) and dexamethasone (DXM), and orally treated twice daily with normal saline, QLWH or DXM. The pneumonia model was established by tracheal instillation of lipopolysaccharide (LPS). After treatment five days, ELISA, H&E staining and Western blot were used to investigate protective effects of QLWH.ResultsNine hundred and ninety-four active ingredients were found through network pharmacology, corresponding to 135 targets for the treatment of pneumonia; compared to the vehicle group, QLWH (10 and 20 mg/kg) significantly decreased the levels of TNF-α (14.3% and 28.8%), IL-1β (23.9% and 42.8%) and IL-6 (13.2% and 16.1%), increased the levels of IL-10 (134.3% and 172.9%); in terms of mechanism, QLWH down-regulated TLR4/NF-κB/NLRP3 axis related proteins in lung tissue of pneumonia model mice (p < 0.05).Discussion and conclusionsThis study combined network pharmacology and animal experiments, providing effective evidence for the clinical promotion of QLWH. Meanwhile, it is of significance for further development.  相似文献   
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