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11.
天然冰片在小鼠组织内的GC—MS测定法和组织分布研究 总被引:1,自引:0,他引:1
目的:建立天然冰片在小鼠组织内含量测定的GC—MS法并进行组织分布研究,初步探索天然冰片的归经特征。方法:采用DB-5MS弹性毛细管色谱柱(0.25mm×30m×0.25μm);电子轰击(E1)电离方式,轰击能量为70eV,倍增电压1100V;选择性离子检测(SIM),天然冰片m/z95,内标萘m/z128;小鼠组织样品用生理盐水匀浆后,加入萘作为内标,用正己烷振荡萃取,取上清液进样测定。组织分布研究以天然冰片的CMC—Na溶液给小鼠灌胃,在不同时间点分批处死小鼠后取各组织样本,经处理后用GC—MS法测定组织中的天然冰片含量。结果:本研究建立的天然冰片GC—MS测定方法,在22ng·mL^-1 -22μg·mL^-1范围内响应信号(Y)与天然冰片浓度(X)呈良好线性关系,Y=0.000486X+0.00036,R^2=0.999(n=3),最低检测限为10ng·mL^-1,定量下限为22ng·mL^-1,日内精密度为3.72—6.11%,日间精密度为7.29~17.6%,相对回收率和提取回收率分别为85.95~107.93%和93.04~103.03%。组织分布研究结果表明,天然冰片分布于大部分组织,单个组织内天然冰片浓度随时间延长呈现多峰现象;天然冰片在肝脏内含量最高,在心、脑、肾等重要组织内的含量也较高。结论:本研究建立的GC—MS测定方法准确、可靠,可用于天然冰片在动物体内的定量分析;天然冰片在不同组织内的分布有明显差异,肝、肾、心、脑中分布含量较高;天然冰片的归经特征中有归心经的趋势。 相似文献
12.
Naeema Al Gasseer Elissa Dresden Gwen Brumbaugh Keeney Nicole Warren 《Journal of Midwifery & Women's Health》2004,49(Z1):7-13
Women and children bear the greatest burden in the midst of war and long‐term disasters. Complex humanitarian emergencies are characterized by social disruption, armed conflict, population displacement, collapse of public health infrastructure, and food shortages. Humanitarian assistance for refugees and internally displaced populations requires particular attention to the common issues affecting morbidity and mortality in women and infants. Gender‐based violence and reproductive health concerns are discussed within the context of populations affected by conflict and forced migration. Recommendations for midwives and women's health care providers engaging in care for women and children in complex humanitarian emergencies are discussed. 相似文献
13.
Hui Liu Tetsuzo Agishi Hideiku Suga Yutaro Hayasaka Satoshi Teraoka Kazuo Ota 《Artificial organs》1995,19(4):324-327
Abstract: Prevention of hyperacute rejection is a difficult and unsolved problem in xenotransplantation. Natural antibodies and complement activation have been known to play an important role in the xenotransplantation between discordant species pairs. In the present study, total blood exchange (TBE) was performed with pyridox-alated-hemoglobin-polyoxyethylene conjugate (PHP) solution (Ajinomoto Co., Inc., Kawasaki, Japan) before cardiac xenotransplantation in order to remove the immunoglobulins and prolong xenograft survival time. Guinea pigs and rats were used as the discordant species combination for donor and recipient. Two groups were established: Group 1, untreated control (n = 8) and Group 2, TBT with PHP solution (n = 8). The exchange blood transfusion was carried out at the rate of 15–20 ml/h utilizing PHP solution using a blood pump. After the blood exchange was processed, hematocrit (Ht) levels dropped to 4 or 5%, and a cardiac xenotransplantation was performed within 24 h. The levels of serum IgA, IgM, and IgG were decreased to less than 25, 25, and 10% of the base line, respectively, after blood exchange. A mean xenograft survival time in Group 2 was prolonged to 472 ± 74 min and to 10.4 ± 1.8 min in Group 1 (p < 0.01). A titer of the anti-guinea pig lymphocytotoxic antibody in rat serum was decreased to almost nil. The data from this study suggest that total blood exchange with PHP solution may be useful in preoperative removal of xenograft antibodies in xenotransplantation. 相似文献
14.
用刀豆蛋白A刺激激素敏感型肾病单个核细胞,并将其培养上清液灌注于大鼠肾内。结合电镜观察,用图像分析仪及体视学方法分别对其肾组织胶体铁染色切片和电镜照片上的足突和滤过裂隙的平均宽度进行测定。结果表明:该病极期上清液灌注的鼠肾小球多阴离子明显减少,足突肿胀、融合,滤过裂隙变窄;而该病缓解组和正常对照组则为阴性。说明该病单个核细胞培养上清液可引起鼠肾小球微小病变型肾病综合征的病变,并揭示该变化可能是由其上清液中一种异常的T淋巴细胞因子所致。 相似文献
15.
J. Lee Jenkins MD MSc Robert E. O'Connor MD MPH David C. Cone MD 《Academic emergency medicine》2006,13(11):1169-1172
This breakout session at the Academic Emergency Medicine 2006 Consensus Conference examined how baseline overcrowding impedes the ability of emergency departments to respond to sudden, unexpected surges in demand for patient care. Differences between daily and catastrophic surge were discussed, and the need to invoke a hospital-wide response to surge was explored. 相似文献
16.
Teresa W. Tam Rui Liu John T. Arnason Anthony Krantis William A. Staines Pierre S. Haddad Brian C. Foster 《Journal of ethnopharmacology》2009,126(1):119-126
Aim of the study
Cree traditional medicine is commonly used concomitantly with prescribed drugs to treat health problems related to type II diabetes (T2D) that is endemic in the Cree population. However, the safety of traditional Cree medicines with respect to drug metabolism is unknown.Materials and methods
Seventeen anti-diabetic plant extracts were screened for their potential inhibition of 11 isoforms of the drug-metabolizing cytochrome P450s (CYPs), and flavin-containing monooxygenase 3 (FMO3) in fluorometric plate reader assays. Comparative analyses were conducted to determine if particular extracts were more inhibitory, or if particular enzymes were more inhibited.Results
Many anti-diabetic plant extracts inhibited the CYPs, with CYP2C and 3A isoforms being most prone to inhibition. The order of inhibition for the enzymes by the Cree plant extracts was: 2C19 > 3A7 > 3A5 > 3A4 > 2C9 > 2C8 > FMO3 > 1A2 > 2E1 > 19 > 2D6 > 2B6. Extracts from Rhododendron groenlandicum, Sorbus decora, and Kalmia angustifolia were identified as having strong inhibition towards many CYP isoforms.Conclusion
These findings demonstrate that extracts from most plant species examined have the potential to affect CYP2C- and 3A4-mediated metabolism, and have the potential to affect the bioavailability and pharmacokinetics of conventional and traditional medicines during concomitant use. 相似文献17.
Antonio Vidaller Fernando Guadarrama Luis Llorente Juan Pablo Méndez Fernando Larrea Antonio R. Villa Donato Alarcón-Segovia 《Journal of clinical immunology》1992,12(3):210-215
We studied NK cell function in eight patients with pathological hyperprolactinemia by measuring51Cr release by K562 cells exposed to their mononuclear cells and found it decreased compared to normal controls (P<0.01). Bromocriptine (BrC) treatment corrected NK function but also made it more efficient at 12:1 than at 25:1 or 50:1 effector:target ratios (ANOVA;P=0.01). The study of NK cell function in agarose revealed that its decrease in hyperprolactinemia is due to their low active binding to target cells, active killing, and recycling capacity. BrC tended to correct them but also increased recycling capacity to levels higher than those of controls (P<0.05). Sequential studies in three hyperprolactinemic patients before and after BrC showed correction of NK function within 1 week but its increased efficiency at the 12:1 effector:target ratio required 8 weeks. We conclude that hyperprolactinemia decreases NK cell function. BrC corrects this by decreasing prolactin levels but also makes NK function more efficient by increasing the capacity of NK cells to recycle after killing. 相似文献
18.
HPCE法测定蛹虫草及其培养物中核苷类化合物的含量 总被引:5,自引:0,他引:5
目的 建立蛹虫草中核苷类化合物的高效毛细管电泳测定法 ,比较天然蛹虫草及其培养物中核苷类化合物的含量。方法 在HV - 30 1高效毛细管电泳仪上进行定量分析 ,采用石英毛细管柱 ,以pH9.0的 4 0mmol·L-1 硼砂溶液作为电极缓冲液 ;分离电压为 1 6KV ;检测波长为 2 5 4nm。结果 天然蛹虫草中核苷类化合物主要集中在子座部分。人工培养蛹虫草子座和菌丝中虫草素的含量分别是天然蛹虫草子座中的 5 .0 4倍和 1 0 .85倍 ;液体培养蛹虫草菌丝中腺嘌呤、腺苷、尿苷、鸟苷含量均高于固体培养蛹虫草子座。结论 天然蛹虫草及其培养物中核苷类化合物的种类和含量具有较大的差异。高效毛细管电泳法可以用于蛹虫草的定量分析 ,具有分离度高、简便、准确 ,样品消耗少等特点 相似文献
19.
胎儿主要肢骨发育时间表──超声骨龄 总被引:1,自引:0,他引:1
用B超检测正常妊娠中的胎儿。选择受精龄为12至38整周(completedweek)的胎儿297例。测量其主要肢骨(干)长度。并将所测数据进行统计学处理。结果表明胎儿肢骨的生长发育与胎龄有显著的正相关关系。 相似文献
20.
选用长白猪8只于麻醉下开胸,于在体猪心上探讨心肌缺血时冠脉仍保留有部分扩张储备,而未被充分利用的机理。实验结果表明:降低左冠状动脉前降支(LAD)内压至4.67kPa时,由LAD分别输入腺苷、山莨菪碱、生理盐水(2ml/min),皆能诱发出明显的LAD流量增加(P<0.05)。在维持LAD内压不变,并持续分别输入上述三种溶液的同时,从LAD远端取血测血液流变学指标,结果显示,输入生理盐水和山莨菪碱使红细胞压积降低,血浆粘度和全血粘度下降;心肌缺血时,冠脉内输注药物所诱发出的“冠脉扩张储备”部分是由于此种给药方式所引起的血液稀释及血液粘度下降的结果。它提示在冠脉狭窄时,血液粘度对狭窄远端的心肌血供可能是一个相当重要的因素,降低血液粘度可能并不亚于扩血管药物的作用。 相似文献