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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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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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Exposure of murine erythroleukemia cells (MELCs) to nicotinamide (NA) or its synthetic analog N′-methylnicotinamide (N′-MN) reduces cell growth and induces terminal differentiation, marked by increased heme and globin accumulation. On the contrary, 1-methylnicotinamide (1-MN), the primary metabolite of excess NA, was found to stimulate cell growth and reduce spontaneous differentiation of cultured MELCs. Log phase MELCs exhibited up to 50% higher cell density above untreated cells when cultured for up to 96 h with 2.5 mM 1-MN. When combined with NA or several chemically-unrelated inducers of hemoglobin synthesis in cultured MELCs, 1-MN reduced the globin mRNA levels and heme accumulation by 40–80%. 1-MN was able to inhibit heme production if present during only the first 24–48 h after NA exposure. Pre-treatment with 1-MN could not confer resistance of cells to effects of NA, suggesting the inhibition is reversible. Commitment to differentiate in semisolid medium by the most potent inducer, 5 mM N′-MN, was inhibited up to 95% by 2.5 mM concentrations of 1-MN. It appears that 1-MN has opposing effects on growth and induction of differentiation than those seen in MELC cultures exposed to NA or N′-MN.  相似文献   
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AIM: The aim of this study was to investigate the nature and organization of maternal needs and priorities in a neonatal unit. BACKGROUND: The relationship between maternal needs and priorities appears to be an under studied area in neonatal nursing. METHODS: A quantitative survey was carried out based on 209 mothers with premature infants. Two self-assessment schedules were used: critical care maternal needs inventory (J. Leske, Heart and Lung 15, 27-42) and a ranking scale. The data were analysed with multivariate analysis. FINDINGS: Data analysis revealed clear priorities in maternal needs. In particular the need for accurate infant related information was a priority for 93% of the mothers. Good communication practices with professionals were also valued. The mothers displayed altruistic behaviour, and self-related needs took second place. It is proposed that maternal needs demonstrate a hierarchical organization. CONCLUSION: It is important for nurses to consider the individual needs of the mothers, simply because the satisfaction of these needs is essential for maternal well-being.  相似文献   
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