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51.
52.
Cynthia J. Berg Jelka Zupan Philip J. d'Almada† Muin J. Khoury Lisa J. Fuller† ‡ 《Paediatric and perinatal epidemiology》1994,8(1):53-61
Summary. Very low birthweight (VLBW) is a commonly used endpoint in perinatal epidemiology, but the population of VLBW infants comprises a wide range of gestational ages and rates of fetal growth. We used data from a population-based study of all 1072 black and white VLBW liveborn infants born in 29 counties in Georgia between April 1986 and March 1988. Less than 1% of the VLBW infants were ≥ 37 weeks gestation; most were 29–32 weeks (26%) or 25 to 28 weeks (40%); 12% were 22 weeks or less. All infants 33 weeks gestation or greater were growth retarded. The population of VLBW infants seems to comprise three groups: approximately 11% very immature infants of 22 weeks or less; the majority of infants, born between 23 and 30 weeks, 90% of which are of normal weight for their gestational age; and a group of less premature, growth-retarded infants from 31 to 36 weeks. We found little or no difference in the distribution of gestational age or the percentage of intrauterine growth rates (IUGR) between black and white infants. In the USA the VLBW rate among black infants is over three times greater than that among white infants and consequently the rates of the three types of VLBW among black infants are likely to be triple those among white infants. 相似文献
53.
54.
Verna W. Y. Yiu Robert P. Dluhy Richard P. Lifton Lisa M. Guay-Woodford 《Pediatric nephrology (Berlin, Germany)》1997,11(3):343-346
In evaluating hypertensive children and adolescents, the etiological considerations should include a set of inherited disorders
that share very low plasma renin activity (PRA) as a common feature. In particular among these disorders, glucocorticoid remediable
aldosteronism (GRA) appears to be emerging as an important etiology of hypertension in the pediatric population. We report
the evaluation of a 9-year-old Caucasian girl who presented with severe hypertension and a strong family history of early-onset
hypertension. Her suppressed PRA, her family history, and her failure to respond to conventional antihypertensive therapy
raised GRA as a potential etiology. The diagnosis was confirmed by an elevated ratio of urinary 18-oxotetrahydrocortisol to
urinary tetrahydroaldosterone and genetic testing, which demonstrated the chimeric gene duplication. The molecular pathogenesis
of GRA and the clinical implications are reviewed.
Received May 15, 1996; received in revised form and accepted September 16, 1996 相似文献
55.
56.
Choline is needed for the maintenance of the structural integrity and signaling functions of cell membranes, for neurotransmission, and for transport of lipids and as a source of methyl groups. Choline can be made de novo in the body, but some individuals must also obtain choline in the diet to prevent deficiency symptoms. A number of environmental and genetic factors influence dietary requirements for choline, and average intakes in the population vary widely. Therefore, certain individuals may be at greater risk of choline deficiency. Choline is critical during fetal development, particularly during the development of the brain, where it can influence neural tube closure and lifelong memory and learning functions. 相似文献
57.
Dominic O''Sullivan Susan Hooper Lisa McNally Daryll Jagger 《European journal of dental education》2007,11(1):54-59
In 2000, the University of Bristol Dental School Division of Restorative Dentistry carried out a review of the assessment methods used within the undergraduate programme. Following this review, a number of key recommendations were made and the system of formative assessment within the division was changed. Audits were conducted immediately prior to the introduction of the new system and 2 years after it had been introduced, the results of these audits are presented. There was no change in the number of failed appointments between the initial audit and the second audit. There was a reduction in the number of patients treated by more than one student from 25% to 14% (approximating to 3% if student withdrawal from the course is taken into account). The length of time taken to complete treatment reduced between the two audits with more than half of all patients having their treatment completed within 3 months of their initial examination in the second audit. Ninety-five percent of treatment plans were completed in the second audit compared with only 62% in the first audit. In the second audit, the outstanding 5% of cases were signed off as incomplete for satisfactory reasons by the member of supervisory staff (e.g. patients who had moved away or were discharged due to poor attendance). Student comments were mostly positive, the small number of negative comments related to some students being confused by the paperwork in the new system. The overall process has been an extremely positive experience which has resulted in an assessment system with increased clarity which appears to have reduced the stress levels reported by the undergraduate students on the programme and improved the quality of patient care within restorative dentistry. 相似文献
58.
59.
Lisa Little 《Health services research》2007,42(3P2):1336-1353
Objective. To synthesize information about nurse migration in and out of Canada and analyze its role as a policy lever to address the Canadian nursing shortage.
Principal Findings. Canada is both a source and a destination country for international nurse migration with an estimated net loss of nurses. The United States is the major beneficiary of Canadian nurse emigration resulting from the reduction of full-time jobs for nurses in Canada due to health system reforms. Canada faces a significant projected shortage of nurses that is too large to be ameliorated by ethical international nurse recruitment and immigration.
Conclusions. The current and projected shortage of nurses in Canada is a product of health care cost containment policies that failed to take into account long-term consequences for nurse workforce adequacy. An aging nurse workforce, exacerbated by layoffs of younger nurses with less seniority, and increasing demand for nurses contribute to a projection of nurse shortage that is too great to be solved ethically through international nurse recruitment. National policies to increase domestic nurse production and retention are recommended in addition to international collaboration among developed countries to move toward greater national nurse workforce self sufficiency. 相似文献
Principal Findings. Canada is both a source and a destination country for international nurse migration with an estimated net loss of nurses. The United States is the major beneficiary of Canadian nurse emigration resulting from the reduction of full-time jobs for nurses in Canada due to health system reforms. Canada faces a significant projected shortage of nurses that is too large to be ameliorated by ethical international nurse recruitment and immigration.
Conclusions. The current and projected shortage of nurses in Canada is a product of health care cost containment policies that failed to take into account long-term consequences for nurse workforce adequacy. An aging nurse workforce, exacerbated by layoffs of younger nurses with less seniority, and increasing demand for nurses contribute to a projection of nurse shortage that is too great to be solved ethically through international nurse recruitment. National policies to increase domestic nurse production and retention are recommended in addition to international collaboration among developed countries to move toward greater national nurse workforce self sufficiency. 相似文献
60.
OBJECTIVE AND DESIGN: To determine the expression pattern and distribution of the glucocorticoid-inducible protein annexin 1 (ANXA1) in a murine model of chronic granulomatous inflammation. MATERIALS OR SUBJECTS: TO Mouse. TREATMENT: Chronic granulomatous inflammation was induced by injecting into dorsal sub-cutaneous air-pouches in mice, a mixture of croton oil and Freund's complete adjuvant (CO/FCA). METHODS: Western and northern analysis, corticosterone assay, and immunohistochemistry. Statistical analysis was performed using ANOVA followed by Tukey's pair-wise comparisons or Dunnett's multiple comparisons. RESULTS: ANXA1 protein levels changed significantly throughout the 4-week time course, with an initial peak at day 7 and a later elevation at 28 days. ANXA1 mRNA levels peaked at days 1 and 3, with a significant decline at day 7 followed by an upward trend to day 28. Plasma corticosterone measurements taken throughout the time course revealed an increase from 14 days onward, suggesting that corticosterone does not influence ANXA1 expression during the initial stages of the model. Immunogold staining revealed that ANXA1 expression in the inflamed tissue was mainly in extravasated neutrophils, with intact protein (37 kDa) being predominantly observed on the cell membrane. CONCLUSIONS: The pattern of ANXA1 expression indicates that infiltrated neutrophils are responsible for the majority of ANXA1 present both at early and later stages of this model of granulomatous inflammation. 相似文献