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Wong-Ho Chow Leonard M. Schuman Joseph K. McLaughlin Erik Bjelke Gloria Gridley Sholom Wacholder Harvey T. Co Chien William J. Blot 《Cancer causes & control : CCC》1992,3(3):247-254
In 1966, a cohort of White males aged 35 or over, who were policy-holders with the Lutheran Brotherhood Insurance Society (United States), completed a mail questionnaire on tobacco use, diet, and demographic characteristics. During the 20 years of follow-up, 219 lung cancer deaths occurred. Besides the strong relationship with cigarette smoking, we observed an effect on lung cancer risk among current users of cigars or pipes who were nonsmokers of cigarettes (relative risk [RR]=3.5, 95 percent confidence interval[CI]=1.0–12.6) or who were past/occasional users of cigarettes (RR=2.7, CI=1.4–5.3). In addition, elevated risks (from 1.5 to 2.6) of lung cancer were found among craftsmen and laborers, with the highest risks among subjects who worked in the mining or manufacturing industry. No association between current (as of 1966) use of beer or hard liquor and lung cancer was observed, although past users were at elevated risk. An inverse association between lung cancer and intake of fruits was observed, and risks of lung cancer were lower among persons in the highest dietary intake quintiles of vitamins A and C. Except for oranges, however, none of the inverse associations with fruits or dietary nutrients had statistically significant trends. The findings from this cohort study add to the evidence of an adverse effect of cigar/pipe smoking and possibly protective effect of dietary factors on lung cancer risk. 相似文献
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Corneal allograft rejection in rabbits 总被引:1,自引:0,他引:1
We performed a phase I study to assess the therapeutic efficacy of an anti-T cell monoclonal antibody conjugated with ricin A-chain in a corneal graft rejection model. Corneal allografts were exchanged between Dutch and New Zealand rabbits. Rejections occurred within 16-22 days in untreated animals. Graft rejection was delayed by topical or retrobulbar cyclosporine, but not by subconjunctival injections of a murine anti-rabbit T cell monoclonal antibody, nor by either subconjunctival or intravenous F(ab')2-ricin conjugate. 相似文献
15.
出血性蛇毒诱导血管内皮细胞凋亡的成分及作用机制研究进展 总被引:1,自引:0,他引:1
出血性蛇毒能专一性诱导血管内皮细胞(vascular endothelial cells,VEC)凋亡,研究人员已从中分离出5种VEC凋亡诱导成份,其中2种为L—aa氧化酶类,3种属于金属蛋白酶/解整联蛋白家族。研究证实前者可通过氧化VEC细胞膜上的L—leu产生H2O2而诱导其凋亡,后者则通过干扰膜整联蛋白与其配体的结合而使VEC凋亡。在由蛇毒诱导的VEC凋亡过程中,p53和bcl-2基因表达增加,且bcl-2的mRNA被剪辑成2条。已证实锚定依赖性信号分子αvβ3和磷脂信号分子PC-PLC参与该过程的信号转导。对该领域进一步研究,有望从蛇毒中纯化出或人工构建出专一地诱导肿瘤血管细胞凋亡的成分。本文总结了出血性蛇毒方面的研究进展。 相似文献
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Rui Providência 《Revista portuguesa de cardiologia》2006,25(11):1043-1058
This article discusses the cardiovascular protection afforded by low to moderate consumption of ethanol and the role of ethanol-induced preconditioning. Ethanol, a compound that is found in many popular beverages, has a whole range of cardiovascular protective effects when consumed in low to moderate doses. Although they have yet to be totally clarified, recent data suggest that a combination of several actions at the biochemical and molecular levels play a role in this protection. These include favorable changes in lipid metabolism, antioxidant effects, changes in hemostasis and platelet aggregation, arterial vasodilation mediated by NO release, induction of the expression of cardioprotective proteins, insulin sensitization and lower levels of inflammatory markers. Special emphasis will be given to ethanol-induced preconditioning. Some of the compounds present in red and white wine, such as resveratrol and quercetin, are also partly responsible for some of the cardioprotective effects of alcoholic drinks. These are due to antioxidant effects and changes in platelet aggregation, endothelial function and inflammatory response. The last part of the paper will focus on the clinical applications and possibilities raised by these new findings. 相似文献
18.
Omer Ozkan O Koray Co?kunfirat Ozlenen Dogan H Ege Ozgenta? 《Journal of plastic, reconstructive & aesthetic surgery》2007,60(5):556-562
Reverse-flow flaps are currently particularly used for the reconstruction of defects of the distal part of the extremities. Despite their common usage there have been many reports of postoperative complications, especially resulting in partial or total flap necrosis. There is insufficient knowledge of flap haemodynamics, physiology and wound healing properties in reverse-flow flaps. Development of the proper experimental models is needed to investigate these issues. The purpose of this study was to describe a new reverse-flow flap model in the rat. A total of 20 adult Wistar rats weighing 200-250 g were used in this experiment. In five rats, the vascular anatomy of the auricle of the rat was determined by anatomic dissection and microangiography. In the experimental group (N=5), 1x1 cm reverse-flow composite flaps were harvested as a semi-island shape, based on the distal course of the medial branch of the anterior auricular artery. In the control group, consisting of five rats, the flap was designed and raised based on the proximal course of the medial auricular artery, again in a semi-island shape. In the remaining five animals, a square-shaped composite tissue of the whole layer of the auricle, 1x1 cm in size, was harvested dividing all the bases circumferentially. The composite tissue was replaced in situ. While the former was considered a conventional antegrade-flow flap subgroup, the latter was designated as a graft subgroup. All flaps were replaced in situ. The survival of the flap was evaluated on postoperative day 7 by direct observation and microangiography. The skin island of all the reverse-flow flaps and conventional antegrade-flow flaps survived completely giving a success rate of 100%, whereas all grafts in the control group underwent complete necrosis. Microangiographic studies revealed the vascularity of the reverse-flow and antegrade-flow flaps, identifying the course of the auricular arteries. In conclusion, with its evident advantages of easy to design and harvesting, reliable survival pattern and consistent vascular structure, our new flap model will provide a means for future studies on flap haemodynamics, physiology in reverse-flow flaps. 相似文献
19.
Classical phenylketonuria (PKU) and hereditary fructose intolerance (HFI) are two inborn errors of metabolism that have an autosomal recessive mode of inheritance. In this paper, we described a 3-year-old girl with PKU and HFI. The occurrence of these two defects in the same patient is thought to be fortuitous and not genetically related since this is the first reported case and the statistical probability of such an occurrence is very low. 相似文献
20.
O O Camponês do Brasil P A Pontes J Speck Filho H O Costa 《Revue de laryngologie - otologie - rhinologie》1991,112(1):45-53
The authors report on 14 patients with epidermoid carcinoma of the glottic region, classified T1, T2 and T3, operated upon by a hemilaryngectomy (9 cases) with reconstruction using a Plathysma myocutaneous flap. The oncological results over a follow-up period of 1 to 6 years and the functional results are analyzed. The authors conclude that this method does not compromise the carcinological result and provides a good functional result with low ratings for complications, with in addition an adequate support for the organ, favouring increased resections. 相似文献