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61.
酸枣仁提取物急性毒性实验研究 总被引:1,自引:0,他引:1
目的 观察酸枣仁醇提取物的急性毒性反应.方法 ①小鼠尾静脉注射不同剂量的酸枣仁醇提取物,连续观察14 d,记录小鼠的急性毒性反应,并计算LD50及LD50 95%可信限;②小鼠灌胃给药,测定一次给予酸枣仁醇提取物的安全剂量.结果 ①静脉注射酸枣仁醇提取物后,部分小鼠出现中毒反应并死亡,测得LD50为27.5 g·kg-1,LD50 95%可信限为25.1~30.1 g·kg-1,死亡动物尸检,其主要脏器未见病理改变.14 d后存活小鼠体重平均增加20.4%,略高于生理盐水组(18.2%).②小鼠灌胃给药(340 g·kg-1,相当于成人一次用量的326倍)后,连续观察14 d,小鼠全部存活,无明显毒性反应,小鼠体重平均增长17.2%.结论 酸枣仁醇提取物毒性很低,临床给药安全可靠. 相似文献
62.
目的 探讨低剂量辐射全身照射对小鼠Lewis肺癌移植肿瘤基因-放疗方案中的免疫增强作用机制。方法 小鼠右后肢皮下接种Lewis肺癌细胞建立荷瘤模型,基因-放疗组中小鼠肿瘤局部注射由多聚乙烯亚胺包裹的pEgr-IL18-B7.1重组质粒,分别接受由2 Gy 局部照射和0.075 Gy 全身照射组合的不同治疗方案,通过3H-TdR标记方法检测小鼠CTL和NK细胞毒活性,ELISA方法检测TNF-α和IFN-γ分泌活性,观察各治疗组对荷瘤小鼠抗肿瘤免疫的作用。结果 在pEgr-IL18-B7.1基因治疗方案中,单次大剂量辐射局部照射后加多次低剂量全身照射与常规多次大剂量辐射局部照射相比,小鼠CTL和NK细胞毒活性显著增强,TNF-α和IFN-γ分泌活性有不同程度的增高。 结论 低剂量辐射可以通过促进CTL和NK细胞毒效应,上调TNF-α和IFN-γ细胞因子表达,从而增强机体抗肿瘤免疫功能,提高肿瘤基因-放疗的抑瘤效果。 相似文献
63.
64.
Kyu-Won Shim Tae-Gon Kim Chang-Ok Suh Jae-Ho Cho Chul-Joo Yoo Joong-Uhn Choi Jung-Hee Kim Dong-Seok Kim 《Child's nervous system》2007,23(10):1155-1161
Object A radiation dose of 40–50 Gy is able to produce a cure rate of more than 90% in intracranial pure germinoma. However, many
attempts have been made to reduce the dose and volume of radiation without compromising the disease control rate because of
the toxicity of irradiation. This retrospective study is intended to provide the physician with an appropriate therapeutic
strategy.
Materials and methods We reviewed a series of 10 recurrent germinomas among 117 germinomas diagnosed histologically or clinically between 1979 and
2002. These patients involved underwent three different treatment modalities; radiation alone (N = 71), chemotherapy alone (N = 9), and combined therapy (N = 37). The 10-year overall and relapse-free survival rates were 97 and 93% in the radiation alone group, 89 and 67% in the
chemotherapy alone group, and 92 and 92% in the combined therapy group, respectively. As expected, both radiation therapy
and combined therapy were effective in controlling the disease. Tumor recurrence was closely related to the volume of radiation
but not to the dose of radiation. If the tumor bed and craniospinal axis were fully covered, the radiation dose might be reduced.
Chemotherapy alone showed earlier recurrence and a higher tumor recurrence rate. In the case of combined therapy, chemotherapy
was useful in reducing the radiation dose but revealed some toxicity (death of two patients).
Conclusions The investigation of a possible further dose reduction seems worthwhile. Radiation therapy alone with a dose of less than
40 Gy should be compared with ongoing chemotherapeutic protocols combined with low-dose irradiation. 相似文献
65.
An indirect enzyme-linked immunosorbent assay (ELISA) for the detection of hexoestrol (HES) was developed, optimized and validated for the analysis of HES in pork. Many parameters, such as the volume ratio of solution A and solution B, colour developing time, pH value, incubation time, the volume ratio of the standard solution and diluted antiserum, blocking solution, blocking condition, coating solution and coating condition were studied and optimized in the paper. The regression equation of the final inhibition curve is y = - 0.3345x + 1.4955, R2=0.9913. The linear range is 0.1-8.1 ng/ml, and the IC50 is 0.671 ng/ml. The specificity of the assay was evaluated by the cross-reactivity rates of six compounds, of which two structurally related compounds had a relatively higher cross-reactivity rate of 25% and 6%. HES was added into a pork sample at 5 ng/g level and then the sample was extracted. The recovery is between 49.6% and 79.2%, and the variation coefficient is 0.164. 相似文献
66.
LI Wei-yong LI Qian QIAO Jian DENG Jun-gang ZHANG Ying 《中国临床药理学与治疗学》2007,12(10):1182-1183
AIM: To determine the safety, tolerability and pharmacokinetic parameters of a new drug recombinant human parathyroid hormone [ rhPTH (1-84)] in healthy male Chinese subjects. METHODS: domly divided Thirty-six healthy male volunteers were rangroups received into 3 groups. The volunteers in these single subcutaneous injection of rhPTH ( 1-84) in a dosage of 1, 2 and 4 μg/kg respectively. Blood samples were obtained before and after administration within 24 hours. The rhPTH concentrations in sennn were determined by enzyme linked immunosorbent assay (ELISA). The pharmacokinetic parameters determined with use of standard noncompartmental analysis were the maximum serum concentration ( Cmax ), the time to attain that concentration ( tmax ), and the area under the serum concentration-time curve up to 24 hours( AUC0-24 ) and up to infinity (AUC0-∞). Dose proportionality of pharmacokinetic parameters (AUC, Cmax of every volunteer of each dosage and A UC was computed from log transformed data) and was examined by mean of analysis of variance (ANOVA) using SPSS software package. In the study, subjects' symptoms, objective signs, and vital signs, including blood pressure, heart rate, respiratory rate and body temperature, were checked and 12-lead electrocardiography was recorded before and after drug administration within 24 hours. Routine laboratory tests, including hematology, blood biochemistry, serum electrolyte, and urinalysis, were performed before and after drug administration within at 24 hours.[第一段] 相似文献
67.
Zakiya Al-Lamki Eileen Thomas Nagwa El-Banna Norman Jaffe 《Pediatric blood & cancer》1995,24(2):137-140
We report an unusual case of anaphylaxis and hepatitic dysfunction in a child with the administration of the twenty-third course of high-dose methotrexate. The latter had been used as an adjuvant to prevent pulmonary metastases and the prior 22 courses had been well tolerated. An attempt to reinstate methotrexate after the twenty-third course was again followed by a similar reaction. © 1995 Wiley-Liss, Inc. 相似文献
68.
辐射是影响黑色素细胞结构和功能的一个重要的环境因素。本文综述了近年来辐射对小鼠黑色素细胞的生物效应研究进展,并对今后的发展予以展望。 相似文献
69.
Dr. Barry Pass John E. Aldrich Patricia L. Scallion 《Calcified tissue international》1990,46(3):166-168
Summary The ESR spectra produced in irradiated dentin have been studied over a range of incident radiation energies from 50 kVp to
25 MVp. The behavior of the dentin ESR signal strength is similar to that of enamel as a function of the energy of the incident
radiation. The magnitude of the dentin ESR signals are, however, up to 10 times smaller than the signals of dental enamel
for a given radiation energy. The possible contributions of radiation interaction coefficients, chemical structure, and crystallite
size to the differences in ESR spectra are discussed. 相似文献
70.