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181.
Joseph B. MacInnis 《CMAJ》1966,95(5):191-200
Recent undersea experiments in the United States and France showed that divers can live and work effectively for many days from dwellings placed on the continental shelf to depths down to 432 feet. If prolonged exposure to the hostile underwater environment is to be tolerated successfully, existing physical, biological and equipment hazards must be recognized, prepared for and, when possible, circumvented. 相似文献
182.
Thermal algae of Western India 总被引:3,自引:3,他引:0
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Fine Structural Alterations in Cell Particles During Chemical Carcinogenesis : II. Further Evidence for Their Involvement in the Mechanism of Carcinogenesis. The Swelling of Rat Liver Mitochondria During Feeding of Amino Azo Dyes 下载免费PDF全文
Joseph C. Arcos George W. Griffith Richard W. Cunningham 《The Journal of cell biology》1960,7(1):49-60
Swelling under carefully controlled conditions has been used to study alterations in the structure of rat liver mitochondria as a result of feeding azo dyes. The changes of the swelling properties of the mitochondria during feeding of the hepatocarcinogenic 3'-methyl-4-dimethylaminoazobenzene are essentially comparable to those observed previously with the microsomes, under the same dietary conditions. These alterations in mitochondrial swelling are not related to changes in the amount of these cell particulates per unit weight of tissue, during feeding of this azo dye. As with the microsomes, feeding of the isomeric but relatively noncarcinogenic 2-methyl-4-dimethylaminoazobenzene does not affect swelling. The structural differences between liver and hepatoma mitochondria show up not only in the rate and extent of swelling but also in the form of the curves of pH dependence. The influence of ketones and sulfhydryl compounds on the swelling of normal liver mitochondria were studied, with particular emphasis to the role of sulfhydryl groups in membrane permeability. The sudden steep rise in the tumor incidence in groups of rats fed 3'-methyl-4-dimethylaminoazobenzene for increasing intervals of time occurs at about 4 weeks. This time correlates with the point of the minimum swelling of microsomes and mitochondria isolated from the livers of rats fed this same dye. Thus, a correlation is established between the alterations of the swelling properties of these particulates and the carcinogenic process. 相似文献
185.
Joseph Rebhun 《The Western journal of medicine》1960,92(3):207-209
In contradistinction to the observation made before that iproniazid has a potentiating effect on certain amines in guinea pigs, human studies have shown that this effect has very little clinical importance, when both the amines and the amine oxidase inhibitor are given in the usual therapeutic doses. However, neither in man nor in the guinea pig pretreatment with iproniazid showed a potentiating effect on amines which are not substrates of monoamine oxidase (ephedrine and amphetamine). Patients with epilepsy and allergic disease may receive iproniazid. 相似文献
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Edwin L. Ball Albert C. Dornbush George M. Sieger F. E. Stirn James C. Vitucci Joseph F. Weidenheimer 《Applied microbiology》1961,9(4):269-272
Data are presented to show that β-propiolactone when properly applied is a very effective agent for sterilization of regenerated collagen sutures. The chemical sterilization is accomplished with little or none of the loss in strength encountered with heat sterilization. The finished sterile suture is obtained without any harmful residue that might be detrimental to the patient. 相似文献
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