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We have used three selective inhibitors of arachidonic acid metabolism in order to investigate the role of lipoxygenase metabolites in the pathogenesis of traumatic shock (LD90). The following inhibitors were used: CGS-5391B (2.5 mg/kg), a cyclooxygenase and lipoxygenase inhibitor, CGS-5677 (2.0 mg/kg), a selective lipoxygenase inhibitor, and U-60, 257 (0.3 mg/kg), a putative inhibitor of glutathione-s-transferase. These inhibitors did not alter arterial blood pressure or heart rate when given to sham shock rats. The traumatic shock model was characterized by a 4.5-fold increase in plasma cathepsin D activity, a 4-fold increase in plasma myocardial depressant factor (MDF) activity, and a mean survival time of 1.5 ± 0.2 h. Only the dual inhibitor significantly blunted the accumulation of cathepsin D in the plasma (7.5 ± 0.8 vs 11.3 ± 0.8 U/ml, p<0.01). However, all three inhibitors significantly suppressed plasma MDF accumulation by 50–60%: CGS-5391B, CGS-5677, and U-60,2257 (p<0.01). Moreover, these three agents significantly improved survival time in traumatic shock. The increased survival time and reduced MDF activity afforded by these inhibitors suggest a significant role for lipoxygenase metabolites, particularly LTC4 and LTD4, in the pathogenesis of traumatic shock. 相似文献
83.
We examined maximum expiratory flow (Vmax) in two canine preparations in which regional changes in lung mechanical properties were produced. In one experiment serial bronchial obstructions were made to determine whether flow-limiting sites (choke points, CP) would occur in series. With the right lung tied off, constrictions were placed at the left lower lobar bronchus (LLL) and left main-stem bronchus. On deflation from total lung capacity, the obstructed LLL and nonobstructed left upper lobe (LUL) emptied into the obstructed left main-stem bronchus. Although a CP common to both lobes was identified at the main-stem obstruction, which limited total Vmax, we questioned whether there was also a CP at the lobar obstruction that fixed LLL flow. In that case the rate of LLL emptying would not be dependent on the presence of the common (i.e., central) CP and thus the flow contribution of the LUL. We found that when the LUL was removed, the LLL increased its rate of emptying. Thus a lobar CP did not fix LLL flow and CP did not occur in series. In a second experiment emphysema was produced in the left lung to reduce lung recoil, whereas the right lung was normal. CP were identified at approximately lobar bronchi of each lung, and the lungs were emptied at different rates. A CP common to both lungs was not identified. Our results indicate that in localized lung disease, if flows from the different regions are high enough, then wave speed is reached in proximal airways, and a CP occurs centrally rather than peripherally. On the other hand, if flows are low, then wave speed is reached peripherally and a CP common to all lung regions does not occur. 相似文献
84.
Anthony Marcus 《Dialectical Anthropology》2008,32(1-2):59-86
For most of the twentieth century the state was not a major part of the anthropological toolkit. Despite significant archaeologically driven work on evolution and state formation, most socio-cultural anthropologists have viewed the state with empiricist scepticism, populist hostility, or ethnographic indifference. Typically, state-theory has been left to other disciplines, such as political science and sociology. Since the end of the cold war there has been a greatly increased interest in the state among anthropologists. Philip Abrams, Michael Herzfeld, and Akhil Gupta, who coined the phrase “ethnography of the state”, have been particularly important to this development. However, there remains no serious engagement with the body of state-theory generated, over the last century, by political activists, scientists, sociologists, and anthropologists. It will be argued that this has allowed for the growth of an unproblematised orthodoxy around an ethnographically informed variant of classic American pluralist state-theory. This orthodoxy has hobbled the understanding and explanation of complex political phenomena, led to confusion between hypotheses and conclusions, and tied parts of the discipline to a partisan political project that remains largely un-interrogated. This essay seeks to provide context and clarification on state-theory as a step towards discussion of anthropology’s contemporary engagement with the state and broader questions of political action and social change. 相似文献
85.
Winfried Häuser Petra Klose Jost Langhorst Babak Moradi Mario Steinbach Marcus Schiltenwolf Angela Busch 《Arthritis research & therapy》2010,12(3):R79
Introduction
The efficacy and the optimal type and volume of aerobic exercise (AE) in fibromyalgia syndrome (FMS) are not established. We therefore assessed the efficacy of different types and volumes of AE in FMS. 相似文献86.
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Congenital diaphragmatic hernia must be seriously considered in the differential diagnosis of acute respiratory distress in neonates as well as in older infants who present with chronic progressive gastrointestinal and respiratory symptoms. An x-ray film of the chest is mandatory and is almost always diagnostic. Immediate nasogastric decompression of the stomach, with simultaneous fluid and electrolyte replacement and prompt surgical intervention offers the patient the best chance of survival. 相似文献
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Maurer Daniel Malique François Alfarraj Salah Albasher Gada Horn Marcus A. Butterbach-Bahl Klaus Dannenmann Michael Rennenberg Heinz 《Plant and Soil》2021,461(1-2):107-118
Plant and Soil - Cyperaceae are common on nutrient-poor soils, including in western Japan. We examined the ability of the native Cyperaceae from western Japan to form dauciform roots and assessed... 相似文献