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OBJECTIVES: To compare the histological effects of diode and Neodymium-Yttrium Aluminium Garnet (Nd:YAG) laser coagulation of chorionic plate vessels. METHODS: In selected chorionic plate vessels in an ex vivo term placenta perfused with warm saline solution, diode (wavelength 940 nm) and Nd:YAG (wave length 1,064 nm) laser were used with an output of 30, 40, and 50 W, and 55 and 70 W respectively using preset energy and duration of impact. All vessels were examined histologically blindly to the procedures' characteristics. RESULTS: A total of 23 vessels were coagulated. Similar histological lesions were observed using diode and Nd:YAG lasers. The lesions were compatible with an acceptable clinical effect at all power outputs tested. The results were not related to the diameter or type of vessels. Lesions of the endothelium and reduction of the vessel lumen were best achieved with a diode laser at 40 W. CONCLUSION: Nd:YAG and Diode laser induce significant and comparable changes in chorionic plate vessels compatible with an efficient coagulation process under the experimental condition used.  相似文献   
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A total of 134 controlled natural IVF (nIVF) cycles were reviewed retrospectively and compared with 370 stimulated IVF (sIVF) cycles. The clinical pregnancy rate per embryo transfer following nIVF was 27% and 47% in sIVF cycles for patients aged less than 35. However, natural cycle patients could attempt consecutive cycles with much less impact on their lives, both medically and financially. In patients under 35 years of age, the choice of controlled nIVF reduces the cost and risk to the patient, permitting her to have multiple, consecutive attempts, and cumulatively offers a clinical pregnancy rate which approaches that of sIVF. The multiple pregnancy rate in nIVF is significantly reduced compared with sIVF treatment cycles. In patients over 35 years of age the benefits of nIVF were much less evident (clinical pregnancy rate: 8% per embryo transfer) and the opportunity to transfer multiple embryos in these patients seems to be advantageous.  相似文献   
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When guinea pigs are fed large amounts of botulinus toxin, they develop symptoms of intoxication within 6 hours and die usually within 12 hours after the feeding of toxin. If very large amounts of toxin are introduced intraperitoneally, the animals may show symptoms of intoxication at the end of the 1st hour and die usually within 2 hours following the administration of toxin. If these animals are placed under anesthesia following the administration of toxin, the intoxication proceeds much more slowly. Anesthesia, by ether, is effective in this manner whether the toxin is given per os or intraperitoneally. The life of guinea pigs kept under ether after the administration of lethal amounts of toxin is prolonged by a period approximately equal to that during which the administration of the anesthetic is continued. When anesthesia is discontinued, the intoxication proceeds at its usual rate. It appears, therefore, that administration of ether delays the rate of intoxication but does not alter the toxin or the nature of the mechanism of intoxication. Anesthesia thus delays the progress of intoxication not only when administered immediately after the intake of toxin, but when administered much later after the intoxication has already progressed far enough to cause definite objective symptoms of poisoning. At this late stage of intoxication, the unsupported serum therapy of botulism in guinea pigs usually remains without effect. If, however, the animals are anesthetized at this time and kept under the influence of ether for some time, antitoxin therapy becomes effective. Indeed the antitoxin treatment can be delayed further for several hours, provided the animal is kept under anesthesia during the interval. Results of a similar nature were obtained with luminal sodium, nitrous oxide-oxygen mixture, and morphine used in place of ether. In view of the fact that the published data indicate that botulinus antitoxin has thus far failed to give beneficial results in the treatment of botulism in human beings because, as it would seem, of the rapid progress of intoxication, any method of delaying the progress of intoxication to supplement the antitoxin therapy deserves consideration.  相似文献   
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Phytonutrients comprise many different chemicals, including carotenoids, indoles, glucosinolates, organosulfur compounds, phytosterols, polyphenols, and saponins. This review focuses on the human healthcare benefits of seven phytochemical families and highlights the significant potential contribution of phytonutrients in the prevention and management of pathologies and symptoms in the field of family health. The structure and function of these phytochemical families and their dietary sources are presented, along with an overview of their potential activities across different health and therapeutic targets. This evaluation has enabled complementary effects of the different families of phytonutrients in the same area of health to be recognized.  相似文献   
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