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As EC validity criteria for the production of Daphnia magna neonates in standard toxicity tests set fecundity minima which must be attained, it is important that culture conditions provide an adequate ration of high quality food. Maintaining a steady supply of fresh algae can be problematical so the possibility of using frozen food was investigated. The performance of three generations of D. magna fed on diets of fresh or frozen Chlorella was compared. There were no significant effects on fecundity due to food type or generation. Cumulative fecundity (over 21 days) on fresh or frozen food exceeded 120 neonates per female and satisfied that EC validity criterion (60 neonates per female). In addition criteria relating to survival and variability were met. We conclude that frozen Chlorella are an acceptable substitute for fresh algae.  相似文献   
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Cerebrovascular accidents complicating pregnancy and the puerperium   总被引:4,自引:0,他引:4  
The decreasing incidence of direct causes of maternal death over the past half century has led to a heightened awareness of nonobstetric factors responsible for maternal mortality. For example, cerebrovascular accidents are an important nonobstetric cause of maternal morbidity and mortality. During the 6.5-year period from 1984 to mid-1990, we encountered 15 women in whom pregnancy or the puerperium was complicated by an acute cerebrovascular accident. Six of these women had hemorrhagic strokes and nine had ischemic strokes. During this same time, approximately 90,000 women were delivered at Parkland Memorial Hospital, and thus the incidence of stroke was about one in 6000 pregnancies. Chronic hypertension or preeclampsia was causative in three cases of hemorrhagic stroke. It is important that 20% of the women died as a result of stroke, and of the 12 survivors, 40% have residual neurologic deficits. An aggressive work-up to define the etiology of stroke is necessary in order to implement cause-specific management, with subsequent reduction in morbidity and mortality.  相似文献   
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Despite being constantly cited as a critical intervening variable in the recovery from alcohol problems, there is a paucity of literature on client motivation. This paper reviews the current literature which impacts on motivation and its importance in treatment and develops in a stepwise manner the revised expectancy/motivation hypothesis, tentatively explaining both motivation and denial as a natural process in behavioural change. Because of the revised expectancy/motivation hypothesis' distinctly defined stages which closely relate to the process of nursing and the qualitative and quantitative measurement it entails which the nursing process demands, it offers a particularly appropriate model for treatment within nurse practice.  相似文献   
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Parasellar syndrome caused by plasma cell leukemia   总被引:1,自引:0,他引:1  
A 71-year-old man had incomplete third cranial nerve palsy caused by plasma cell leukemia and a parasellar plasmacytoma. This is the first reported case of plasma cell leukemia in which a central nervous system sign was the initial manifestation. Only one previous case of intracranial plasmacytoma associated with plasma cell leukemia has been reported. The characteristics of intracranial plasmacytomas and of plasma cell leukemia are discussed.  相似文献   
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Approximately 11,550 women with epilepsy give birth annually, yet maternity nurses receive little information on how to care for these patients. Children of epileptic mothers are born with an increased incidence of birth defects, and have a higher perinatal mortality rate. Complications such as bleeding during pregnancy, and interventions such as cesarean births and labor inductions are more common among epileptic women, and seizures tend to increase during pregnancy in more than one-third of epileptic women. Informed nursing care is essential to ensure the best possible outcome of these pregnancies.  相似文献   
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