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91.
高效液相色谱法测定美洛昔康胶囊的含量 总被引:1,自引:0,他引:1
目的 :建立反相高效液相色谱法测定美洛昔康胶囊中美洛昔康的含量。方法 :采用LichrosorbC18色谱柱 (5 μm,4 .6mm× 2 0 0mm) ,以吡罗昔康为内标 ,甲醇 乙腈 0 .0 9mol·L-1庚烷磺酸钠溶液 冰醋酸 (5 4∶8∶37∶1)为流动相 ,流速为0 .9mL·min-1,检测波长为 35 2nm ,柱温为室温。结果 :美洛昔康在 8~ 4 8mg·L-1范围内呈良好的线性关系 ,r =0 .9999,平均回收率为 99.78% ,RSD为 0 .96 %。结论 :该法简便 ,快速 ,专属性好 ,结果准确 ,可靠。 相似文献
92.
目的 :建立中成药午时茶胶囊中厚朴酚与和厚朴酚含量测定的高效液相色谱法。方法 :色谱条件为 AlltimeC1 8(Alltech 5μm,4.6mm× 2 5 mm)柱 ,流动相 :甲醇 -水 (72∶ 2 8) ;流速 :1.0 ml/ min;检测波长 :2 94nm。结果 :测得厚朴酚与和厚朴酚加样回收率为 99.82 % (RSD=0 .89% ,n=6)。结论 :该法可为午时茶胶囊的质量控制和制备工艺提供依据 相似文献
93.
94.
实体语法系统与中医药理论现代化 总被引:1,自引:0,他引:1
实体语法系统是一种形式化语法系统,可用于形式化地描述复杂系统的组成单位、组织方式、变化规律。本文尝试将实体语法系统引入中医药理论研究,为实现中医药理论的形式化提供一种新的思路,并在此基础上探讨实现中医药理论与微观领域知识的衔接和用中医药理论解释人体复杂系统的可能性。实体语法系统为中医药理论形式化和中医药理论现代化提供了较具体的研究工具,为中医药理论现代化提出了探索性的思路。 相似文献
95.
Polymorphisms in interleukin -2, -6, and -10 are not associated with gastric cardia or esophageal cancer in a high-risk chinese population. 总被引:7,自引:0,他引:7
96.
Wen Qing Yang Xueqing Lun Cheryl Ann Palmer M Elizabeth Wilcox Huong Muzik Zhong Qiao Shi Richard Dyck Matt Coffey Brad Thompson Mark Hamilton Sandra G Nishikawa Penny M A Brasher Kevin Fonseca David George N Berry Rewcastle Randal N Johnston Doug Stewart Patrick W K Lee Donna L Senger Peter A Forsyth 《Clinical cancer research》2004,10(24):8561-8576
PURPOSE: Human reovirus type 3 has been proposed to kill cancer cells with an activated Ras signaling pathway. The purpose of this study was to investigate the efficacy of reovirus in immunocompetent glioma animal models and safety/toxicity in immunocompetent animals, including nonhuman primates. EXPERIMENTAL DESIGN: Racine glioma cells 9L and RG2 were implanted s.c. or intracranially in Fisher 344 rats with or without reovirus antibodies, followed by treatment of reovirus. To study whether reovirus kills contralateral tumors in the brain and to determine viral distribution, we established an in situ dual tumor model followed by reovirus intratumoral inoculation only into the ipsilateral tumor. To evaluate neurotoxicity/safety of reovirus, Cynomolgus monkeys and immunocompetent rats were given intracranially with reovirus, and pathological examination and/or behavioral studies were done. Viral shedding and clinical biochemistry were systematically studied in monkeys. RESULTS: Intratumorally given reovirus significantly suppressed the growth of both s.c. and intracranially tumors and significantly prolonged survival. The presence of reovirus-neutralizing antibodies did not abort the reovirus' antitumor effect. Reovirus inhibited glioma growth intracranially in the ipsilateral but not the contralateral tumors; viral load in ipsilateral tumors was 15 to 330-fold higher than the contralateral tumors. No encephalitis or behavioral abnormalities were found in monkeys and rats given reovirus intracranially. No treatment-related clinical biochemistry changes or diffuse histopathological abnormality were found in monkeys inoculated intracranially with Good Manufacturing Practice prepared reovirus. Microscopic changes were confined to the region of viral inoculation and were dose related, suggesting reovirus intracranially was well tolerated in nonhuman primates. CONCLUSIONS: These data show the efficacy and safety of reovirus when it is used in the treatment of gliomas in immunocompetent hosts. Inoculation of reovirus into the brain of nonhuman primates did not produce significant toxicities. 相似文献
97.
98.
6名健康妇女分别于上臂、臀部和腹部三部位经皮给予合LNG的透皮控释传递系统(TCDS)后,用放射免疫法测定LNG血清浓度,计算其主要药物动力学参数。结果表明:在TCDS用药期间,三部位的C(max)、T(max)及AUC(0~168h)基本接近,部位间无显著性差异(P>0.05);TCDS揭除后,AUC(168~204h)及消除相半衰期T(1/2)(Ke)均以腹部最大,臀部次之,上臂最小,在腹部与上臂间有显著性差异(P<0.05)。上述结果可归因于TCDS对LNG的控释和人体皮下脂肪的“贮库效应”。 相似文献
99.
Dibenzo[a,l]pyrene-induced DNA adduction, tumorigenicity, and Ki-ras oncogene mutations in strain A/J mouse lung 总被引:1,自引:0,他引:1
Prahalad AK; Ross JA; Nelson GB; Roop BC; King LC; Nesnow S; Mass MJ 《Carcinogenesis》1997,18(10):1955-1963
Dibenzo[a,l]pyrene (DB[a,l]P), an environmental polycyclic aromatic
hydrocarbon, is the most potent carcinogen ever tested in mouse skin and
rat mammary gland. In this study, DB[a,l]P was examined for DNA adduction,
tumorigenicity, and induction of Ki-ras oncogene mutations in tumor DNA in
strain A/J mouse lung. Groups of mice received a single i.p. injection of
0.3, 1.5, 3.0, or 6.0 mg/kg DB[a,l]P in tricaprylin. Following treatment,
DNA adducts were measured at times between 1 and 28 days, while tumors were
counted at 250 days and analyzed for the occurrence of point mutations in
codons 12 and 61 of the Ki-ras oncogene. DB[a,l]P in strain A/J mouse lung
induced six major and four minor DNA adducts. Maximal levels of adduction
occurred between 5 and 10 days after injection followed by a gradual
decrease. DB[a,l]P-DNA adducts in lung tissue were derived from both anti-
and syn-11,12- dihydroxy-13,14-epoxy-
11,12,13,14-tetrahydrodibenzo[a,l]pyrene (DB[a,l]PDE) and both
deoxyadenosine (dAdo) and deoxyguanosine (dGuo) residues in DNA as revealed
by cochromatography. The major adduct was identified as a product of the
reaction of an anti-DB[a,l]PDE with dAdo in DNA. DB[a,l]P induced
significant numbers of lung adenomas in a dose- dependent manner, with the
highest dose (6.0 mg/kg) yielding 16.1 adenomas/mouse. In
tricaprylin-treated control animals, there were 0.67 adenomas/mouse. Based
on the administered dose, DB[a,l]P was more active than other environmental
carcinogens including benzo[a]pyrene. As a function of time-integrated DNA
adduct levels, DB[a,l]P induced lung adenomas with about the same potency
as other PAHs, suggesting that the adducts formed by DB[a,l]P are similar
in carcinogenic potency to other PAHs in the strain A/J mouse lung model.
Analysis of the Ki- ras mutation spectrum in DB[a,l]P-induced lung tumors
revealed the predominant mutations to be G-->T transversions in the
first base of codon 12, A-->G transitions in the second base of codon
12, and A-->T transversions in the second or third base of codon 61,
concordant with the DNA adduct profile.
相似文献
100.
肾上腺素诱导兔血小板聚集的实践与理论探讨 总被引:1,自引:0,他引:1
目的创建以Adr诱导兔血小板聚集的方法,并对受体分子特性作初步探讨。方法以高K+缓冲液等取代兔PRP中血浆,以Adr诱导聚集,以Apyr证实结果。结果兔血小板悬浮于高K+缓冲液时Adr能单独诱导真正的聚集。结论由此推测血小板膜上α2肾上腺素受体分子可能为由两种亚单位组成:促聚亚单位和辅助亚单位。人辅助亚单位当Adr浓度高达聚集阈值以上时可被激活,与促聚亚单位结合为活性的二聚体,与Adr进一步结合发生聚集作用。兔辅助亚单位则还需要高K+方能被激活 相似文献