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991.
The death of a three-year-old child by asphyctic mechanism is described. The child was accidentally suspended by the neck from a half-opened car window. This report details the form in which the accident occurred. The influence of the type of window and the autopsy findings.  相似文献   
992.
993.
This work intends to provide a wide scope of the legal situation in Brazil referred to Human Embryos and how it has been developed through the 20th century. Across the last century, the human being got the possibility of making genetic experiments with human embryos. Our main goal is to assume the future responsibility of these actions through a juridical and ethical point of view.  相似文献   
994.
995.
996.
Samples of complete human semen were incubated in gastric juice for different time periods at 37 degrees C, and by simulating the post-mortem temperature decrease of the human body. The changes in the spermatozoa were similar in both experiments. Short incubation specimens were examined directly with interference contrast microscopy and showed an almost immediate immobilization of spermatozoa when they were brought in contact with gastric juice. Specimens with longer incubation periods were stained with alcalic fuchsine and examined by immersion microscopy. There was a morphologically stable plateau for the heads of the spermatozoa for up to 6 h of incubation. The tails disappeared progressively in the first 45 min. After more than 6 h of incubation a progressive swelling and lysis of the heads was observed. Spermatozoa could be recognized for up to 7 days of incubation.  相似文献   
997.
In experimental games, as in natural situations, people are often observed acting to the benefit of others even at considerable cost to themselves. Such behavior is contrary to the assumption of selfish behavior, but it is not necessarily contrary to the assumption of rationality: People cooperating under these circumstances could be ‘rational altruists’ who base their decision on the magnitude of the external benefit, as well as on the costs to themselves. We test that proposition using a prisoners' dilemma experimental paradigm. If it is correct, we should observe higher levels of cooperation as the external benefit in such games increases. But we do not — whether external benefit is measured in terms of number of individuals benefiting from a cooperative choice or the total dollar benefit produced. Cooperation must be explained otherwise.  相似文献   
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999.
Immunofixation procedures were used for detecting alpha-1 antitrypsin protease inhibitor (Pi) phenotypes in bloodstains. Neuraminidase elution of bloodstains, together with isoelectric focusing, immunofixation, and silver staining techniques, makes possible Pi subtyping in old bloodstains. No extra bands appear when the storage time is no longer than three months.  相似文献   
1000.
Eds. Note: This article was written in the early 1990s, during the last year of George Bush's presidency. Since then NAFTA negotiations have been completed and the treaty is now in operation. An updating of the article would require considerable statistical revision, as well as further analysis of events. Neither the statistics nor the events; however, require a revision of the interpretative perspective advanced in the article.  相似文献   
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