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61.
62.
This investigation has reexamined the measurement of the femur length and the use of this measurement as a growth and dating parameter. Straight-line measurements of shaft length were found to be smaller than measurements made along the bone curvature. However, the maximum difference did not exceed 2 mm. Thus, because of its simplicity, use of straight-line measurements appears justified. The optimal (R2 = 96.1%) growth curve model was a linear-quadratic function, with variability around the regression line increasing with menstrual age. The optimal (R2 = 96.8%) dating curve model was a linear-quadratic function in which loge menstrual age is a function of femur length. The variability associated with age estimates increased with femur length. These data were used to construct new standard curves for growth assessment and dating of fetuses using femur length measurements.  相似文献   
63.
The hypertensive disorders of pregnancy are a leading cause of maternal mortality and morbidity. Complications are not limited to preeclampsia but also complicate both preexisting hypertension and isolated gestational hypertension. Blood pressure (BP) management is important but is only one aspect of management of the hypertensive disorders of pregnancy, which may be caused or exacerbated by underlying uteroplacental mismatch between maternal supply and fetal demand. BP treatment thresholds and goals vary in international guidelines, largely reflecting differences in opinion rather than differences in published data. Because of short-term maternal risks, there is consensus that BP should be treated when sustained at greater than or equal to 160 to 170 mm Hg systolic and/or 110 mm Hg diastolic. There is no consensus regarding management of nonsevere hypertension, and randomized controlled trials involving just over 3000 women have not clarified the relative maternal and perinatal risks and benefits. Although antihypertensive therapy may decrease transient severe maternal hypertension, therapy may also impair fetal growth and perinatal health and outcomes. The CHIPS Trial (Control of Hypertension In Pregnancy Study) is recruiting to answer this question.  相似文献   
64.
OBJECTIVES: To examine the prevalence and sociodemographic and health‐related correlates of substance use, including alcohol, tobacco, and nonmedical drug use, in adults aged 65 and older. DESIGN: Cross‐sectional, retrospective survey of a population‐based sample, the 2001/02 National Epidemiologic Survey on Alcohol and Related Conditions. SETTING: United States. PARTICIPANTS: Eight thousand two hundred five U.S. adults aged 65 and older. MEASUREMENTS: Prevalence of lifetime and previous‐12‐month alcohol, tobacco, and nonmedical drug use and associations between substance use and sociodemographic and health‐related factors. RESULTS: Almost 80% of older adults had used any of the three substances over their lifetimes, and more than 50% reported such use over the previous 12 months. Alcohol was the most commonly used substance over the lifetime (74%) and in the previous 12 months (45%), followed by tobacco (52% lifetime; 14% previous 12 months); far fewer reported nonmedical use of drugs (5% lifetime; 1% previous 12 months). In general, being younger, male, and divorced or separated were factors consistently associated with use of any of the three substances. CONCLUSION: Most older adults had used substances over their lifetimes and in the previous 12 months. Alcohol is the substance of choice for this age group, followed by tobacco; few report nonmedical drug use.  相似文献   
65.
AIM: To assess the impact of three educational presentations as an intervention for increasing knowledge of end-of-life care for rural nurses in assisted living and nursing home environments. DESIGN: A repeated measures design (quantitative component) evaluated the effects of the educational intervention. Two open-ended questions yielded qualitative data. SAMPLE AND SETTING: A convenience sample (n = 9) of Registered Nurses and Licensed Practical Nurses employed in an assisted living facility or nursing home in the rural, southeastern region of the USA. Level of nursing experience ranged from 6 to 28 years. ANALYSIS: Frequency distributions, difference of means test for paired samples. RESULTS: Post test scores were significantly higher (t = 6.999; p < 0.001) than pretest scores regarding overall knowledge on end-of-life care. Attitudes and perceptions of participants changed in defining what constitutes a 'good death'. CONCLUSIONS: Classroom educational presentations are an effective means of changing attitudes and improving end-of-life care knowledge. Additional education and support for rural nursing personnel involved with residents of long-term care may enhance end-of-life care.  相似文献   
66.

Background and objectives

Sellar metastasis is uncommon and poorly characterized as published data include small series of subjects. This study’s goal is to identify unique features that differentiate this entity from other sellar masses such as pituitary macroadenomas.

Methods

Published cases of pathologically-confirmed sellar metastasis along with our experience in such patients over a 6-years period were reviewed (total = 129). As a control group, we reviewed similar data on 55 patients with pituitary macroadenomas managed over the same time-period. Presenting symptoms, pituitary dysfunction were analyzed using univariate, multivariate and receiver operating characteristic (ROC) analyses.

Results

Sellar metastasis has equal gender distribution with a median patient-age of 56 years. The most common primary malignancy was breast cancer (29 %) in women and lung cancer (30 %) in men. Sellar metastasis was the first manifestation of cancer in over 40 % of patients. Common presenting symptoms included headaches, visual field deficits, abnormal eye motility and diabetes insipidus. These symptoms were less frequent among patients with pituitary macroadenomas. Univariate regression analyses showed that headaches, abnormal eye motility, visual field deficits and diabetes insipidus were each predictive of metastatic disease. ROC analysis combining all 4 features revealed an AUC of 0.953 with a sensitivity of 0.818 and a specificity of 0.935. Using the multivariate regression, abnormal eye motility and/or diabetes insipidus independently predicted metastatic disease.

Conclusions

Sellar metastasis should be suspected in patients presenting with sellar masses, abnormal eye motility and/or diabetes insipidus even those without known malignancy since pituitary metastasis can often be the first manifestation of cancer.  相似文献   
67.
Patient is a 29‐year‐old with a history of recurrent growth hormone‐secreting pituitary macroadenoma diagnosed 12 years prior to presentation. Eight years prior to current presentation, the patient underwent re‐resection and received 50.4 Gy external beam radiotherapy (EBRT) in 28 fractions of 1.8 Gy each. Serial postradiation MRIs demonstrated regression in pituitary tumor size. Patient presented with new headaches 7.5 years after completing EBRT. Brain MRI demonstrated new FLAIR hyperintensity and contrast enhancement within the pons and medulla, corresponding to the 36 Gy isodose line of each radiation dose fraction. Differential diagnosis included radiation necrosis and radiation‐induced glioma (RIG). The patient's neurologic exam worsened over the following 4 months. MRI showed progressive increase in mass effect, extent of FLAIR hyperintensity, and contrast enhancement in the brainstem. Stereotactic‐assisted biopsy showed infiltrating astrocytoma with moderate atypia. A PubMed search showed this is the first case of histologically verified brainstem RIG correlated with 3‐dimensional conformational radiation therapy dose and volume planning following EBRT for a pituitary adenoma. The rare occurrence of brainstem RIG after radiation therapy for pituitary tumor supports the need for long‐term imaging monitoring of such patients.  相似文献   
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69.
OBJECTIVES: To document current bicycle helmet use in Winnipeg, Manitoba and nearby rural communities, and to identify target groups for a helmet promotion campaign. METHODS: Cyclist helmet use was observed between 28 May and 20 August 1996 at a sample of urban and rural locations. Age, gender, helmet use, riding companion(s), location type, correct helmet use, and use of headphones were recorded. Univariate and multivariate analyses were performed. Adjusted odds ratios with 95% confidence intervals were calculated from the final models. RESULTS: Altogether 2629 cyclists (70% male, 30% female) were observed: 2316 at 183 urban locations and 313 at 25 rural locations, with nearly equal numbers of children and adults observed. Overall helmet use was 21.3%, with lower use in males (18.9%) than females (26.3%), despite gender only being a significant variable on multivariate analysis for children under 8 years and adults. Urban helmet use was considerably higher (22.9%) than rural use (8.9%). Helmet use increased linearly as mean neighbourhood income increased, with a nearly fourfold difference in use between the highest and lowest income neighbourhoods. Children less than 8 years old and adults had the highest, and teenagers the lowest, use. Significant predictive variables were identified separately by age category to inform targeted programming. CONCLUSIONS: We documented low helmet use in our region, emphasizing the need for a regional helmet promotion campaign as well as future helmet legislation. A marked urban-rural difference in helmet use that has not been previously reported was also identified. Target groups for a future campaign include adolescents, males, rural cyclists, and those in lower income neighbourhoods.  相似文献   
70.
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