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971.
972.
In a prospective study 90 patients who had confirmed abruption of the placenta were compared with a control group. Significantly more patients who had abruptio placentae were unmarried, smoked cigarettes, received no antenatal care, had coitus within the 48 hours preceding delivery, developed intrapartum hypertension and had a lower ponderal index than the controls. More patients with abruptio placentae had proteinuria and antepartum hypertension but statistical significance was not reached. In addition, the incidence of intra-uterine growth retardation was higher in these patients.  相似文献   
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Summary Cytosine arabinsodie (ara-C) and etoposide (VP-16) display synergy in the laboratory. Twenty-six patients participated in a phase I study of high-dose ara-C in combination with VP-16. The dose of VP-16 was held constant at 50 mg/m2 as an intermittent infusion over 33 h; escalating doses of ara-C were given as infusions during hours 9–12 and 21–24. Myelosuppression was the dose-limiting toxicity and occurred with doses considerably less than those expected from studies of the two drugs as single agents. The suggested initial doses for phase II trials with this schedule are 750 mg/m2×2 doses of ara-C and 50 mg/m2 of VP-16. Nonhematologic toxicity was minimal; therefore, further dose escalation is feasible in patients in whom myelosuppression is acceptable.Supported in part by grants from the National Cancer Institute (CA-12197 and CA-09422) and the American Cancer Society CF-85-182  相似文献   
975.
A flow-through finite-dose diffusion cell has been designed for use in transdermal drug delivery research. The diffusion cell consists of an upper donor chamber and a lower receiver compartment through which a continuous supply of fresh solvent flows. The flow is directed to an automatic fraction collector. To validate the flow-through cell, its performance was compared directly against that of a conventional single-reservoir Franz cell. Homologous alkyl p-aminobenzoates were diffused through dimethylpolysiloxane membranes, and permeability coefficients increased with increasing chain length, reaching a plateau at the butyrate ester for both types of cells. This behavior suggests a shift from membrane-controlled diffusion to boundary layer control. Permeation of the butyrate and valerate compounds was significantly faster when the flow-through cell was used, suggesting that better mixing is obtained through the flow-through cell design. Considering the advantages offered in terms of time and labor saved through its use, the flow-through cell with automatic fraction collector appears to be a viable alternative to the conventional Franz cell.  相似文献   
976.
Rat brain hippocampal slices were incubated with or without the convulsant 4-aminopyridine (4-AP). From these slices a crude mitochondrial/synaptosomal membrane fraction was prepared and analyzed for endogenous protein phosphorylation. 4-AP (10(-5) M) stimulated the phosphorylation of a 50 kDa protein by 86%. The phosphorylation of this 50 kDa protein is Ca2+/calmodulin-dependent and we suggest that this protein is the lower molecular weight subunit of Ca2+/calmodulin-dependent protein kinase II (CaMK II).  相似文献   
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This research was designed to test the extent to which health education and health services administration students' perceptions of their roles as professionals matched the expectations of professional faculty. These perceptions were found to match in general. However, doubt was cast on the extent to which internships or practicums contributed to this result, since there was no change in student responses between the beginning of the junior year and end of the senior year, a period which includes fieldwork and most of the professional coursework presumed to influence professional development. Additional research is required to test this result with other student populations in other health professions and identify the point at which professional role and task definitions are amenable to change.  相似文献   
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