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71.
25种常用食物总脂质、总磷脂和主要磷脂含量的比较 总被引:1,自引:0,他引:1
<正> 磷脂是构成生物细胞膜的基本组分,以其规律的结构保证细胞的正常形态和功能。因而经常有一定质量的磷脂保证,是维持所有细胞健康生长和生理功能的基础。磷脂已被广泛应用为食品添加剂,由于磷脂是一种天然产物,更加适应当今世界对“非化学添加物”的需要。但目前的食物成分表均无磷脂的含量,为此对云南、陕西、辽宁等地常用食物中总脂质、总磷脂和主要磷脂的含量进行了分析。 相似文献
72.
Sarabjit S. Neelam Alvise Bernabei Curtis Freedland Roxanna Thompson Thomas H. Corbett Gordon D. Luk 《Investigational new drugs》1990,8(3):263-268
Summary Unresectable solid tumors in the metastatic stage are quite resistant to current chemotherapy and radiation therapy regimens. Flavone acetic acid (FAA) is a novel antitumor agent which appears to work through a different mechanism than the conventional chemotherapeutic agents. In preclinical studies it has shown effectiveness against a variety of transplantable murine and human tumors and appears to be solid tumor selective. It also has non-overlapping toxicities as compared to conventional agents. We therefore investigated FAA in vitro against human colon cancer cells and explored whether its effectiveness could be enhanced in combination with other agents such as adriamycin (ADR), cis-platinum (CP) and difluoromethyornithine (DFMO) — an inhibitor of polyamine biosynthesis. Addition of FAA for 24 hours in liquid media produced dose dependent growth inhibition. Using soft agar colony assay, growth was inhibited by 58% by 3mM FAA and only 1.4% by 0.375mM FAA. The combination of FAA and cis-platinum produced synergism at the lower doses tested. The combination of FAA and adriamycin produced antagonism at all doses tested and the combination of FAA with DFMO did not produce results significantly different from DFMO alone. We conclude that enhancement of FAA activity can be achieved in combination with conventional antitumor agents, but may be drug and dose specific. 相似文献
73.
醒脑启智胶囊对学习记忆障碍小鼠行为的影响 总被引:4,自引:2,他引:2
目的观察醒脑启智胶囊对血管性痴呆学习记忆障碍小鼠行为的影响 ,验证醒脑启智胶囊对血管性痴呆的疗效。方法复制脑缺血再灌注血管性痴呆小鼠模型 ,灌胃给药 ,并与银杏叶、尼莫地平对照 ,分别于术后 7天、15天、3 0天 ,采用水迷宫法检测各组小鼠行为学变化。结果模型小鼠学习与记忆能力下降 ,表现为游全程时间延长 ,错误次数增加。醒脑启智胶囊可使模型小鼠游全程时间缩短 ,错误次数减少 ,优于对照药物。结论醒脑启智胶囊对模型小鼠学习与记忆能力下降有提高作用。 相似文献
74.
Tarja A. Soininvaara Hannu J.A. Miettinen Jukka S. Jurvelin Esko M. Alhava Heikki P.J. Kröger 《Journal of clinical densitometry》2004,7(4):424-431
Osteoarthrosis (OA) is often associated with pain and disability, which are relieved after total knee arthroplasty (TKA), but the nature of bone changes associated with OA is controversial. We examined preoperative hip and contralateral knee bone mineral density (BMD) in patients requiring TKA and monitored the BMD changes postoperatively. Sixty-nine patients, scheduled to have TKA for osteoarthrotic knees, had both hips and contralateral knee BMD measured by dual-energy X-ray absorptiometry (DXA) at the time of operation (baseline) and at 1 yr after operation. X-rays of the knee joints were also taken to evaluate the severity of OA. Preoperatively, 27% and 38% of the patients had total hip BMD Z-score more than 1 SD in the operated side and contralateral hips, respectively. In all regions of interest (ROI), the mean baseline BMD of the affected side proximal femur was significantly lower than that of the contralateral side (p < 0.0005-0.019). The severity of OA was not associated with BMD. During 1-yr follow-up, the postoperative knee status and the physical activity of the patients (AKS score) improved. However, neither the hip nor the nonoperated knee BMDs increased. Knee OA is associated with significantly lower BMD values in the affected side compared with the contralateral hip, and these levels remained similar or decreased during a 1-yr follow-up. We conclude that improved mobility after TKA does not improve the effects of preoperative disuse-associated bone loss in the short term. 相似文献
75.
J. Ludwig T. Halbrügge G. Vey J. Walter K. -H. Graefe 《European journal of clinical pharmacology》1989,37(5):493-500
Summary The total body clearance and fractional extraction of isoprenaline (ISO) have been determined, and the relation between these parameters and cardiac output established. Whether desipramine, an inhibitor of neuronal uptake, altered the plasma catecholamine response to ISO was also investigated.Seven healthy subjects were given i.v., infusions of ISO in two, consecutive 25-min periods, at constant dose rates of 31–43 and 80–124 pmol·kg–1·min–1, respectively. The total-body (ER), pulmonary (ERp) and forearm (ERf) fractional extractions and the total body clearance (CL) of ISO were obtained from measurements of cardiac output and the steady-state ISO concentration in mixed central venous, arterial and forearm venous plasma.ISO-induced increases in cardiac output resulted in increases in CL, decreases in ER and no consistent change in ERf. ERp did not differ from zero. ISO also produced a dose-dependent increase in the mixed venous plasma concentrations of noradrenaline and 3,4-dihydroxyphenylglycol (DOPEG), and a decrease in that of adrenaline. Pretreatment with desipramine did not alter any of the pharmacokinetic parameters of ISO. Desipramine, however, reduced the mixed venous baseline plasma levels of noradrenaline (47%) and DOPEG (40%), and tended to reduce that of adrenaline (34%). It enhanced the plasma noradrenaline response 2.4-fold, abolished the plasma DOPEG response and did not alter the plasma adrenaline response to ISO.Hence, owing to its haemodynamic effects, ISO modifies its own pharmacokinetics which involve non-neuronal removal processes only. The increased DOPEG in plasma resulting from the ISO-induced increase in noradrenaline release was presynaptic in origin. Desipramine appears to reduce sympathetic activity. The enhancement by desipramine of the ISO-induced increase in plasma noradrenaline points towards recapture by neuronal uptake of at least 58% of the noradrenaline released in response to ISO. 相似文献
76.
全营养素混合液(TNA)在肠外营养的应用 总被引:2,自引:0,他引:2
脂肪乳剂、葡萄糖、氨基酸、电解质、维生素及微量元素按一定程序混合配成10种全营养素混合液。在4℃14天贮存期内,10种混合液的pH和渗透压变化不大,不同混合液在不同时期的脂粒平均直径变化为0.3135±0.1012μm~0.4813±0.1893μm,94.93%脂粒的直径<0.6μm,无直径>6μm的脂粒,细菌培养阴性。74例共输全营养素混合液1,796次,无不良临床反应和异常实验室检查结果;用1周以上者大都显示氮平衡改善,用2周以上者血清转铁蛋白和白蛋白浓度可有不同程度升高。 相似文献
77.
复方脑得生中总黄酮纯化工艺研究 总被引:1,自引:0,他引:1
目的研究复方脑得生中总黄酮的最佳纯化工艺。方法采用正交设计和单因素试验法,以总黄酮的洗脱率和含量为指标,考察利用D-101树脂富集、纯化复方脑得生中总黄酮的工艺条件及参数。结果优选纯化工艺为:上样溶液浓度0.1g/mL,流速2aV/h,树脂径高比1:7;吸附后,先用5BV的水洗脱,再用5BV40%乙醇洗脱。所得提取物中总黄酮的含量为80.57%,总黄酮转移率达83.76%。结论优选纯化工艺得到的总黄酮含量高,工艺简单,适宜工业化生产。 相似文献
78.
目的建立人血浆中克拉霉素浓度测定的LC-MS/MS方法,研究克拉霉素缓释胶囊与市售克拉霉素缓释片的药动学及人体相对生物利用度。方法以罗红霉素为内标,用乙醚-二氯甲烷(3∶2)提取处理,以甲醇-水-甲酸(80∶20∶0.05)为流动相,用C18柱分离,采用ESI源,正离子方式检测,扫描方式为多反应监测(MRM)。结果克拉霉素线性范围为10.0~4000μg·L-1,日内、日间RSD均小于15%。应用此方法研究18名健康受试者口服0.5g受试制剂和参比制剂的药动学参数。单剂量口服受试制剂和参比制剂的tmax,ρmax,t1/2,AUC0-t,AUC0-∞,CL和Vd分别为:(5.36±1.14)和(5.25±0.88)h,(1218±433)和(1333±370)μg·L-1,(4.59±1.67)和(4.24±2.10)h,(8239±1553)和(8467±1364)μg·h·L-1,(8662±1829)和(8795±1331)μg·h·L-1,(60.9±15.1)和(58.9±11.3)L·h-1和(382±103)和(366±224)L。多剂量口服受试制剂和参比制剂的tmax,ρssmax,ρssmin,ρav,AUCss和DF分别为:(5.31±1.11)和(5.28±0.96)h,(1387±396)和(1488±401)μg·L-1,(64.6±26.8)和(70.1±30.0)μg·L-1,(399±99.2)和(410±107)μg·L-1,(9585±2382)和(9830±2578)μg·h·L-1,(3.32±0.62)和(3.49±0.66)。单剂量和多剂量相对生物利用度分别为(98.2±16.3)%和(99.5±19.0)%。结论本法快速、准确、专属、灵敏。统计结果表明,两制剂人体内相对生物利用度无显著性差异(P>0.05)。 相似文献
79.
目的观察强心力胶囊对慢性充血性心力衰竭患者心脏左心室功能的影响。方法运用彩色多谱勒超声心动图,测量慢性充血性心力衰竭患者左心室舒张末及收缩末内径(D s和Dd)、左心室每搏量(SV)、心输出量(CO)、左心室短轴缩短率(FS)和射血分数(EF)等指标。结果强心力胶囊治疗后患者收缩末期内径(D s)、流量指标(SV和CO)和泵功能指标(EF和FS)均有明显改善,但治疗后收缩末期内径D(d)和E A/比值无明显变化。结论强心力胶囊具有治疗充血性心力衰竭的作用。 相似文献
80.
目的:通过观察妇宝胶囊对动物出凝血时间、血液凝固系统的影响,探讨妇宝胶囊的止血机制。方法:采用毛细玻璃管法测定小鼠凝血时间(CT),用断尾法测定出血时间(BT);用ACL-200型血液凝集仪测定大鼠凝血酶原时间(PT)和部分凝血活酶时间(APTT)。结果:妇宝胶囊能明显缩短小鼠CT、BT,缩短大鼠PT和APTT。结论:妇宝胶囊的止血机制主要通过促进内源性和外源性凝血系统,抑制纤维蛋白溶解系统达到目的。 相似文献