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61.
Astrid R. R. Heutelbeck Carsten Junghans Hermann Esselmann Ernst Hallier Thomas G. Schulz 《International archives of occupational and environmental health》2009,82(9):1123-1131
Introduction
Cattle are an important source of allergens in the working area of farmers. Asthma caused by cow allergens is a significant occupational problem. Yet in allergological testing, the results of in vivo and in vitro diagnostic tests are often inconsistent even in cases with clearly cattle-related symptoms. 相似文献62.
Ernst?Kiesswetter M.?Sch?per M.?Buchta K.?H.?Schaller B.?Rossbach T.?Kraus S.?Letzel 《International archives of occupational and environmental health》2009,82(10):1191-1210
Objectives
This is the second of two parallel longitudinal studies investigating Al exposure and neurobehavioral health of Al welders over 4 years. While the first published study in the trail and truck construction industry examined the neurobehavioral development of Al welders from age 41–45 in the group mean (Kiesswetter et al. in Int Arch Occup Environ Health 81:41–67, 2007), the present study in the automobile industry followed the development from 35 to 39. Although no conspicuous neurobehavioral developments were detected in the first study, which furthermore exhibited the higher exposure, it cannot be excluded that exposure effects appear in earlier life and exposure stages. 相似文献63.
Markus Thalmann Heinrich Schima Georg Wieselthaler Ernst Wolner 《The Journal of heart and lung transplantation》2005,24(3):237-245
The beating heart and the resultant pulse wave have been a symbol of life for centuries. The development history of roller pumps for cardiopulmonary bypass shows that the human body tolerates non-pulsatile blood flow, at least for short-term support. Over the last few years, many types of rotary blood pumps have been developed for clinical use in patients requiring mid- to long-term support. Although early clinical experiences in patients with long-term support have been promising, the matter of whether pulsatile flow is needed or not remains controversial. Therefore, this review summarizes the observed clinical consequences of continuous blood flow in patients supported by rotary blood pumps and relates these consequences to underlying experimental studies. 相似文献
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Ohne ZusammenfassungMit 3 Textabbildungen. 相似文献
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Ohne ZusammenfassungZum Schluss ist es mir eine angenehme Pflicht, meinem Chef, Herrn Oberarzt Dr. Nonne, für die Ueberlassung des Falles und für seine freundliche Unterstützung bei Abfassung dieser Arbeit verbindlichst zu danken. 相似文献
67.
Dr. Ernst Graser 《Naunyn-Schmiedeberg's archives of pharmacology》1883,17(5):329-362
Ohne ZusammenfassungDie folgenden Experimente wurden in Gemeinschaft mit Herrn Dr. Hölzke, früherem I. Assistenten an der Erlanger Augenklinik, angestellt, und hat derselbe im Archiv für Ophthalmologie bereits eine kurze Mittheilung über die Resultate gegeben. 相似文献
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Identifying environmental risk to male reproductive function by occupational sperm studies: logistics and design options. 总被引:11,自引:2,他引:9
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Malfunction of the male reproductive system might be a sensitive marker of environmental hazards, the effects of which may extend beyond reproductive function. The testis is more vulnerable to heat and ionising radiation than any other organ of the body and several xenobiotics are known to disrupt spermatogenesis after low level exposure. Studies of environmental impact on human health are often most informative and accurate when carried out in the workplace where exposures can be high and easy to document. Semen analysis provides readily obtainable information on testicular function. The main advantages in comparison with functional measures such as fertility rates and time taken to conceive are the possibilities to examine men independently of marriage and pregnancy, to find changes of fecundity with different exposures within the same person and to detect adverse effects when no alteration of fertility is yet taking place. In the implementation of an occupational sperm study considerable attention must be paid to logistic issues. A mobile laboratory unit for initial semen preparation and processing may in some situations increase worker compliance and the quality of sperm cell motility. The cross sectional design which has been used in almost all male reproductive studies so far has several severe limitations including selection bias because of differential participation, difficulties in defining a suitable reference group, and lack of information about the time dimension of the cause-effect relation. The longitudinal design deals adequately with most of these constraints. Semen samples are collected before, during, and possibly after exposure to the risk factor of interest and causal inferences are based upon change of semen variables within a man over time rather than upon differences between men. The logistics of the longitudinal study may benefit from pre-employment health examinations to enrol newly hired workers and require fewer participants to obtain comparable statistical power. In conclusion, andrological methods and epidemiological designs are available for the implementation of valid studies concerned with environmental impact on human testicular function. Occupational sperm studies should probably not be the first choice when the objective is initial screening of environmental impact on fertility but should be implemented when their is a need to corroborate or refuse earlier evidence that specific exposures have impact on testicular function. 相似文献