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991.
We previously reported that polyinosinic-polycytidylic acid, a potent interferon inducer, inhibits the growth of B16 malignant melanoma in the C57BL/6 mouse. Two experiments were done to evaluate the effectiveness of interferon in tumor inhibition in vivo. In the first, mice were implanted with melanoma and divided into four groups, according to treatment: interferon preparation; interferon control preparation ("breakthrough fraction"); phosphate-buffered saline control; and murine serum albumin control. Daily, each mouse was given i.p. injections of 200,000 NIH reference units (hereafter called units) of interferon or of one of the control substances. The second experiment was similar to the first, except that bovine serum albumin was an additional control. In both experiments, the average tumor volume in interferon-treated mice was statistically significantly smaller than that of each control group. Mouse interferon preparations also inhibited the multiplication of B16 malignant melanoma cells in culture. This inhibition was statistically significant from interferon levels as low as 5 to as high as 5000 units/ml. The degree of inhibition markedly increased from 5 up to 500 units, the inhibition reaching its maximum at this concentration. The inhibitory effect of interferon was abrogated by anti-murine interferon serum produced in a rabbit. These findings suggest that the in vivo inhibition of the growth of B16 melanoma demonstrated with polyinosinicpolycytidylic acid and with exogenous interferon probably results, at least in part, from a direct effect of interferon on the tumor cells themselves. 相似文献
992.
Mutagenic, transforming and promoting effect of pickled vegetables from Linxian county, China 总被引:1,自引:0,他引:1
A recent epidemiological survey in China showed that there is a regional distribution of esophageal cancer and a correlation between mortality for this cancer and environmental factors, especially the consumption of pickled vegetables. A series of experimental studies with pickled vegetable extract were done using different in vitro biological systems. The results showed that pickled vegetable extract induced 6-thioguanine-resistant mutants in V79 cells and increased sister chromatid exchanges in the same cells and in Syrian hamster embryo cells. Pickled vegetables extract induced transformed foci in Syrian hamster embryo cells and in 3-methylcholanthrene initiated C3H/10T1/2 cells. The mutagenic, transforming and promoting activities of pickled vegetable extract seen in vitro conform with in vivo results and provide evidence for the presence of a mutagen and/or a carcinogen in pickled vegetable extract. A possible role of pickled vegetables consumption in the etiology of esophageal cancer is discussed. 相似文献
993.
994.
本实验采用低叶酸培养条件,对一个鼻咽癌高发家族成员和配对的正常人作了染色体畸变研究。结果:家族血缘亲属组和对照组染色体畸变率(CAR)分别为11.01%和5.06%,两者比较有高度显著性差异(P<0.001);配偶组CAR为4.6%。与对照组比较无显著性差异(P>0.25);家族中一非癌成员发现t(7;14)(P22;q22)2次,与文献报告在2例鼻咽癌患者外周血发现的染色体易位完全相同。文章讨论了染色体畸变与鼻咽癌遗传易感性的关系,认为特殊的培养条件可使家族成员CAR与正常人之间的差距加大。 相似文献
995.
We previously reported the discovery of 14 channels in the human body, which possessed the biophysical property of high emission of light. In this study we found the same property on the Ren and Du channels in healthy rats. Additionally, we discovered that the luminance of the related channels in rat models with different "syndromes" varied greatly. For instance, a markedly low luminance appeared on the Du channel in animals with experimental syndrome of Yang deficiency induced by hydrocortisone; while in animals with experimental syndrome of blood deficiency caused by bleeding, an apparently low luminance occurred on the Ren channel. The intensity of the emitted light on Du and Ren channels increased after acupuncture treatment, but not significantly. This phenomenon conforms to the theory in traditional Chinese medicine that the Du channel is the "sea of Yang channels", while the Ren channel is the "sea of Yin channels". 相似文献
996.
Lai ST Cheng KK Yu TJ Kuo SM Weng Z Chang Y Lee PS Cheng PC 《Journal of clinical laser medicine & surgery》1991,9(6):485-491
From March to July 1989, nine patients at risk for peripheral artery disease underwent intraoperative Nd:YAG laser angioplasty using angioscopy at the Veterans General Hospital (Taipei, Taiwan, Republic of China). Following the laser angioplasty, balloon dilatation was performed in all cases. Eight men and one woman at an average age of 68 were included in the study (range: 58 to 78 years old). Ischemic symptoms included five patients with disabling claudication, four with pain at rest and one with gangrene on the toes. Eight of the nine patients had complete occlusions ranging from 2 to 19 cm in length. Two patients had high degree multiple segmental stenosis of the superficial femoral artery from 1 to 2 cm in length. Initial clinical success (indicated by relief of symptoms and increase in Doppler ankle pressure and index) and improvement in the angiographic luminal diameter was noted in 9 of 10 occluded vessels (90%) that underwent Nd:YAG laser treatment which was delivered at 10 to 12 watts through laser probes. Prelaser intraluminal diameter increased from 0.05 +/- 0.07 to 0.53 +/- 0.07 mm, Doppler ankle pressure index rose from 0.51 +/- 0.12 to 0.81 +/- 0.12, Doppler ankle pressure increased from 62.44 +/- 16.10 to 104 +/- 21.21 mmHg and the amplitude of pulse volume recorder at ankle level rose from 5.77 +/- 2.80 to 12.11 +/- 2.77 mm as compared with prelaser therapy (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
997.
J. Graham Sharp James W. Osborne Ph.D. H. F. Cheng K. L. Coop George R. Zimmerman 《European journal of nuclear medicine and molecular imaging》1982,7(1):28-34
Radioiodinated antitumor (Ab-gamma globulins), non-tumor-specific Ab, and R131ISA were used for imaging radiation-induced intestinal tumors in rats. Each agent detected tumors larger than 2 g, but labeled Ab were most efficient in detecting smaller tumors. Tissue distribution studies showed that while purified Ab localized specifically in tumors, unpurified Ab concentrated in the tumor by a mechanism not considered immunological. Localization was variable and the concentration of antitumor Ab reached useful levels only in a small number of cases. The use of high specific activity purified Ab unexpectedly decreased the concentrations of label observed in the tumors when compared with the use of the same activity of low specific activity purified Ab. These results indicated the presence of circulating tumor antigens which were capable of binding the injected Ab. Subsequently, these findings have been substantiated. Thus the animal-to-animal variability could be explained on the basis of differing degrees of interaction of injected Ab with circulating tumor antigens. The usefulness of labeled purified or monospecific antitumor antibodies for tumor imaging and therapy would thus be influenced by the extent of such interactions.This work was presented in part at the Twentieth Annual Meeting of the Radiation Research Society, Portland, Oregon, May, 1972. 相似文献
998.
A number of ureidothiazole and ureidothiadiazole derivatives related to ethyl 4-[[(2-thiazolylamino)carbonyl]-amino]benzoate were prepared and evaluated against the leukemia P-388 tumor system in mice. Preliminary structure-activity relationship study revealed that, among other considerations, active compounds of this series contain either an "isothioureido" [N-C(S-)=N-] or an "isothiosemicarbazono" [N-C(S-)=N-N=] structural unit. 相似文献
999.
1000.
To devise a new classification of vascular variations in second toe transfer we analyzed the anatomic details of the first dorsal metatarsal artery in 304 cases of second toe transplantation and the venous structure in 200 cases. According to location, the arterial vascularity was classified as superficial (18% of cases), intramuscular (54%), inframuscular (23%), and absent (5%). According to diameter, it was classified into large (16%), medium (64%), and small (20%). Based on branching pattern, the artery was classified into ramifying type (88%), main trunk (4%), and fine branch type (8%). The venous drainage of the second toe was categorized as greater saphenous vein main trunk type, greater saphenous vein fine branch type, dorsal digital vein main trunk type, and dorsal digital vein fine branch type. Variations of the first dorsal metatarsal artery are common. Classification should be done according to its location, diameter, and branching pattern at the toe web. Regardless of location, big vessels entering the second toe are the most important attribute for successful outcome. 相似文献