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61.
Emiko Ito Fumie Suzuki-ToyotaKiyotaka Toshimori Haruhiko FuwaKazuo Tachibana Masayuki SatakeMakoto Sasaki 《Toxicon》2003,42(7):733-740
Gambierol was isolated from Gambierdiscus toxicus, which causes ciguatera fish poisoning. The acute toxicological effects induced in mice by synthesized gambierol were studied. The lethal doses were about 80 μg/kg by i.p. and i.v., and 150 μg/kg by p.o. The main injury by this toxin was observed in the lung, and secondary in the heart, resulting in systemic congestion. Another toxic effect was seen in the stomach, inducing hypersecretion and ulceration. With survival from the severe stage during the initial 3 h, recovery was favorable, especially after 4 days. Additional effects were not evident during 1-week post-administration observation. 相似文献
62.
利用热解-色质联用分析系统,对文题进行了研究,发现其热解过程是一个复杂的多元反应过程。在500~800℃,钛酸丁酯(Ⅰ)热解尾气产物主要是烯烃、醇、醚和醛类化合物。经热解机理分析,发现Ⅰ的重排断裂反应是整个热解过程的主反应,其反应动力学常数为3.87×10~5,活化能为69.3 kJ/ 相似文献
63.
慢性非特异性溃疡性结肠炎中医研究述评 总被引:31,自引:1,他引:30
本文通过对古典医籍及近10年文献有关慢性非特异性溃疡性结肠炎的资料分析,认为本病的证候特点与中医病名“休息痢”相符,病机归纳为脾虚为发病之本,湿热为致病之标,血瘀为局部病理变化,治疗方面得出了健脾益气化湿、活血化瘀解毒、托疮祛腐生肌等方法是治疗本病之关键的结论,提出分期治疗本病的思想,认为提高近期治愈率、降低复发率及做好癌前监测是今后研究的努力方向。 相似文献
64.
少见肺部原发性恶性肿瘤七例报告 总被引:3,自引:0,他引:3
报告我院1980年-1993年诊治的7例少见肺部原发性恶性肿瘤,包括来源于间叶组织的2种肉瘤,来源于间胚叶软组织肿瘤,来源于气管粘膜腺体上皮的肿瘤,1例由原始生细胞向胚外组织分化而成的内胚窦瘤,全部病例经病理活组织检查证实,重点讨论诊断的体会。 相似文献
65.
M. V. Merrick T. M. Griffin 《European journal of nuclear medicine and molecular imaging》1994,21(6):521-524
The effect of swallowing a small quantity of water or of solid food (biscuit) on the renogram curve was observed in 177 patients. Swallowing provoked contraction of the renal pelvis in 63% of the kidneys with a pelvicalyceal system which was neither obstructed nor dilated, with expulsion of a substantial fraction of the contents within 30 s. This did not occur in obstructed or denervated kidneys, nor in patients with a high transection of the spinal cord. Evidence is adduced that this contraction is mediated reflexly. This effect may be used diagnostically to distinguish physiological dilatation from obstruction. The implications when performing and interpreting renography are discussed.
Correspondence to: M.V. Merrick 相似文献
66.
Martin Grosse Holtforth Louis G. Castonguay Thomas D. Borkovec 《Clinical psychology》2004,11(4):396-404
The conceptual and methodological framework proposed by Doss (this issue) makes valuable suggestions for strategic choices in future research. This commentary addresses conceptual and terminological distinctions adopted by Doss, as well as his criticism of add-on/ dismantling studies. We also suggest research topics and methodological developments that could be integrated in Doss's framework to further expand understanding of therapeutic change. 相似文献
67.
68.
French Donna L. Häglund Bert O. Himmelstein Kenneth J. Mauger John W. 《Pharmaceutical research》1995,12(10):1513-1520
Purpose. The objective of this study is to correlate drug release mechanism with measured drug concentration profiles in gel layers of Carbopol® matrices containing mesalamine or benzoic acid.
Methods. Release rate experiments with Carbopol® matrices were performed using a rotating disk apparatus. Matrices were frozen and the gel layer in the matrices was sliced using a microtome in a cryostat. Drug concentration profiles were determined by direct measurement of the concentration of the drug in the gel slices. The pH of the slices was measured using microelectrodes, and water content was measured by Karl Fisher titration.
Results. The concentration gradient in mesalamine matrices decreased over time and correlated with square root of time release rate kinetics. The concentration profiles of benzoic acid were unchanged over time and correlated with zero order release rate kinetics. Carbopol gel layers were highly hydrated (93–95% water). Gel layers in matrices with mesalamine had a more alkaline microenvironmental pH. This higher pH resulted in increased growth of the thickness of the gel layer and a reduction drug diffusivity in comparison to benzoic acid matrices.
Conclusions. The release rate kinetics of mesalamine and benzoic acid correlated to the measured concentration profiles. The shape of the concentration profiles is determined by the rate of growth of the Carbopol® gel layer and drug diffusivity. 相似文献
69.
Kazumasa Shindo MD Shin-ichi Tsunoda MD Zenji Shiozawa MD 《Clinical autonomic research》1994,4(6):299-302
Microneurography was performed in a 39-year-old woman with demyelination of the pontine white matter associated with muscle spasms in the lower extremities. Single bursts on the microneurogram were observed immediately after cessation of the spasm with no systemic changes in the blood pressure or heart rate. Voluntary tonic flexion of the lower extremities induced similar bursts with small amplitudes. These reflex bursts possessed a characteristic of muscle sympathetic nerve activity, because the latency between the peak of each burst and the prior R-wave on the electrocardiograph was constant. The occurrence of these bursts suggests that a segmental compensatory mechanism in the spinal cord may stabilize the muscle blood flow influenced by muscle contraction. 相似文献
70.
吴在东 《安徽卫生职业技术学院学报》2005,4(2):76-77,75
探索军工研究所发展民品产业之路.本文对军工研究所发展民品产业进行了优劣势分析,继而从机制转换,组织结构,产品战略,市场营销,人才队伍建设等方面提出了一些改革措施. 相似文献