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M M Lech L Ostrowska 《The European journal of contraception & reproductive health care》2005,10(1):59-65
OBJECTIVES: The aim of the study was to check and present data on the relation between combined oral contraceptives (COC) use and body weight in young women living in Poland. METHODS: Observational study on the group of young women on COC and the control group of young women who never used COC. Candidates for study (145 women) and control (218 women) groups were recruited in selected gynecological clinics in Poland during the period of 1-31 January 2002 (with the use of randomization). RESULTS: Both groups (study and control) were almost identical in age, anthropometric characteristics, number of pregnancies and deliveries. On the basis of this investigation it was found that there was no relation between use of COC and weight gain. Observed (in both groups) weight gain in young women was most probably related rather to time-passing (patients were getting older). The higher risk for overweight and obesity was found in the group of young women who had already had problems with overweight in their childhood. and in the group of women with high weight gain during the first pregnancy. CONCLUSION: COC use is not associated with weight gain in young women with a Central European life-style. 相似文献
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Janet M Powell Sonya L Griffith Elizabeth M Kanny 《The American journal of occupational therapy》2005,59(4):467-474
PURPOSE: To provide a model for assessing occupational therapy workforce needs by using a demand-based approach to determine current workforce status in the Northwest region. Regional information may have implications for addressing national occupational therapy service needs. METHOD: A questionnaire was sent to a proportional random sample of 234 facilities that hire occupational therapy practitioners. Data were collected in July-August 2003 using structured mailing and follow-up procedures. RESULTS: Response rate was 79%. Twenty-four percent reported occupational therapy vacancies and 11% occupational therapy assistant vacancies; 48% predicted an increase in occupational therapy positions in the next 2 years and 41% an increase in occupational therapy assistant positions. Sixty-three percent of respondents reported difficulty in hiring. DISCUSSION: This study identifies an occupational therapy workforce shortage in the Northwest. Management of a shortage is critical, for even short-term adjustments could lead to permanent changes in service provision. This study demonstrates the importance of current information on the status of the national workforce and serves as a model for future studies. 相似文献
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Steven J Lavine 《Journal of the American Society of Echocardiography》2005,18(2):133-141
BACKGROUND: The index of myocardial performance (IMP) has been used as a prognostic systolic-diastolic index for patients with dilated cardiomyopathy and postmyocardial infarction. To date, systematic evaluation of the effect of heart rate and preload alteration on IMP has not been performed with normal or reduced left ventricular (LV) function. METHODS: We studied 14 mongrel dogs at baseline, after the induction of acute ischemic LV dysfunction, and with chronic LV dysfunction. Heart rate was altered by atrial pacing 10 and 20 beats above baseline, and volume loading was accomplished with 10 mL/kg of saline at a paced rate. Hemodynamics, and transmitral and transaortic pulsed Doppler, were obtained. RESULTS: With normal LV function, there were no changes in IMP with pacing. With acute LV dysfunction, IMP was also unchanged with pacing, although both LV ejection time (ET) (192 +/- 23 vs 208 +/- 25 milliseconds, P < .05) and isovolumic contraction time (58 +/- 25 vs 72 +/- 31 milliseconds, P < .05) declined. With chronic LV dysfunction, IMP was unchanged although LV ET declined (188 +/- 15 vs 204 +/- 18 milliseconds, P < .01). Volume loading did not alter the IMP with normal LV function although LV ET increased (208 +/- 25 vs 220 +/- 20 milliseconds, P < .001). With acute LV dysfunction, IMP decreased (0.66 +/- 0.11 vs 0.82 +/- 0.20, P < .05) because of a decrease in isovolumic relaxation time (63 +/- 33 vs 76 +/- 38 milliseconds, P < .05). With chronic LV dysfunction, IMP also declined with volume loading (0.59 +/- 0.29 vs 0.73 +/- 0.28, P < .01) because of an increase in LV ET (224 +/- 30 vs 198 +/- 22 milliseconds, P < .0001). CONCLUSION: Heart rate incrementation does not change IMP. However, volume loading reduces IMP primarily as a result of LV ET lengthening with chronic LV dysfunction. Further systematic evaluation of IMP is needed if this index is to be useful as a prognostic indicator. 相似文献
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