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1.
In 1991/92, 289 students from four different schools of nursing in Norway participated in a case-related attitudes test. The nursing students answered questions concerning their personal views on the moral and legal implications of either assisting suicide or performing euthanasia. They also indicated whether they thermselves were willing to perform these acts. The results were compared with responses from a study on students from other faculties in 1988. The findings suggested that nursing students were significantly (p < 0.0005) more restrictive than the other students in their attitudes towards voluntary active euthanasia (VAE). Factors that influenced the nursing students' attitudes towards VAE were measured by the index of VAE. Religious belief (p < 0.0001), conservative political view (p < 0.01), and the perception of life as meaningful (p < 0.02) were the best predictors of the dependent variable.  相似文献   
2.
Occupational exposure to carcinogenic agents on the decks on six Norwegian crude oil tankers was examined in five harbors. The purpose of the study was to evaluate the need for improving the working environment on deck on these tankers. Technical arrangments and the work itself on the deck were observed during loading or unloading. Occupational monitoring was performed by active sampling of benzene, polyaromatic hydrocarbons, and some aldehydes. The crew answered a questionnaire concerning their work, use of protective equipment, and occurrence of acute symptoms. The levels of air-borne carcinogenic agents were low, probably due to closed loading systems on all tankers. However, the seamen reported discomfort during the work that may be related to other chemical agents in the cargo. The seamen were frequently painting with lead chromate paint without using personal protective equipment. This type of chemical exposure should be evaluated.  相似文献   
3.
OBJECTIVE: The purpose of this study was to construct new reference ranges for serial measurements of commonly used umbilical artery Doppler indices (pulsatility index, resistance index, and systolic:diastolic ratio). STUDY DESIGN: This was a prospective longitudinal study of the umbilical artery Doppler indices that were obtained serially at the free-loop of umbilical cord at 4-week intervals at 19 to 42 weeks of gestation in 130 low-risk singleton pregnancies. A total of 513 observations were used to construct the reference ranges with the use of multilevel modeling. RESULTS: Longitudinally established percentiles of Doppler indices from the present study show a continuous reduction throughout the second half of pregnancy without any plateau or increase near term, as reported previously. There was a significant negative association between Doppler indices and placental weight and neonatal birth weight, but not with gender. The intraobserver coefficients of variation for the umbilical artery pulsatility index, resistance index, and systolic:diastolic ratio were 10.5%, 6.8 %, and 13.0 %, respectively. CONCLUSION: New reference ranges for umbilical artery Doppler indices that are based on longitudinal observations appear to be slightly different from cross-sectional studies and are more appropriate for serial evaluation of fetal hemodynamics.  相似文献   
4.
PurposeThere has been little research on myopia management options for patients with astigmatism. This study quantified changes in peripheral refraction induced by toric orthokeratology (TOK) and soft toric multifocal (STM) contact lenses.MethodsThirty adults with refractive error of plano to −5.00 D (sphere) and −1.25 to −3.50 D (cylinder) were enrolled. Cycloplegic autorefraction was measured centrally, ±20 degrees, and ±30 degrees from the line of sight nasally (N) and temporally (T) on the retina. Measurements were made at baseline, after 10 ± 2 days of TOK wear (without lenses on eye), and after 10 ± 2 days of STM wear (with lenses on the eyes) and compared with repeated-measures analysis of variance.ResultsCompared to baseline, TOK induced a myopic shift in defocus (M) at all locations (all P < 0.01), but STM only induced a myopic shift at 20 T in both eyes and 30 N/T in the left eye (all P < 0.01). TOK resulted in more myopic defocus than STM at all locations (all P < 0.05) except 20 T in the left eye. TOK induced more J0 astigmatism at all locations (all P < 0.02), except 20 N in the right eye; J0 with STM was different than baseline at 20 N in both eyes and 30 N in the right eye (all P < 0.02). TOK induced more J0 astigmatism than STM at all locations (all P < 0.01), except 20 T in the left eye. Differences in J45 astigmatism, when significant, were clinically small.ConclusionsGreater amounts of peripheral myopic defocus and J0 astigmatism were induced by TOK compared to STM, which may influence efficacy for myopia management.  相似文献   
5.
6.
The entorhinal cortex (EC) plays a central role in episodic memory and is among the earliest sites of neurodegeneration and neurofibrillary tangle formation in Alzheimer’s disease. Given its importance in memory and dementia, the ability to selectively modulate gene expression or neuronal function in the EC is of widespread interest. To this end, several recent studies have taken advantage of a transgenic line in which the tetracycline transactivator (tTA) was placed under control of the neuropsin (Nop) promoter to limit transgene expression within the medial EC and pre-/parasubiculum. Although the utility of this driver is contingent on its spatial specificity, no detailed neuroanatomical analysis of its expression has yet been conducted. We therefore undertook a systematic analysis of Nop-tTA expression using a lacZ reporter and have made the complete set of histological sections available through the Rodent Brain Workbench tTA atlas, www.rbwb.org. Our findings confirm that the highest density of tTA expression is found in the EC and pre-/parasubiculum, but also reveal considerable expression in several other cortical areas. Promiscuous transgene expression may account for the appearance of pathological protein aggregates outside of the EC in mouse models of Alzheimer’s disease using this driver, as we find considerable overlap between sites of delayed amyloid deposition and regions with sparse β-galactosidase reporter labeling. While different tet-responsive lines can display individual expression characteristics, our results suggest caution when designing experiments that depend on precise localization of gene products controlled by the Nop-tTA or other spatially restrictive transgenic drivers.  相似文献   
7.

Background

Soft-tissue sarcomas are rare malignant tumors of mesenchymal lineage that can arise in any part of the body. Prognosis, and hence also treatment may vary according to histologic subtype and localization. Angiogenesis is the process of forming new blood vessels from pre-existing ones. The deregulation of this process is thought to be an important step in malignant transformation. This study investigates the prognostic impact of platelet derived growth factor- (PDGF), vascular endothelial growth factor- (VEGF) and fibroblast growth factor (FGF) families in soft-tissue sarcomas of the extremities & trunk (ET) and visceral & retroperitoneal (VR) locations.

Methods

Tumor samples from 181 patients (115 ET and 66 VR) with resected soft tissue sarcomas were collected and tissue microarrays were constructed. Immunohistochemistry was used to evaluate angiogenic marker expression. Recurrence-free survival (RFS), metastasis-free survival (MFS) and disease-specific survival (DSS) were used as endpoints in prognostic impact assessment.

Results

In univariate analyses, almost all investigated angiogenic markers had prognostic impact in the ET group. In contrast, only FGFR-1 showed any significant prognostic impact in the VR group. In the multivariate analyses, PDGF-D (HR?=?1.863, 95% CI?=?1.057-3.283, P?=?0.031), VEGFR-1 (HR?=?2.106, 95% CI?=?1.038-4.272, P?=?0.039) and VEGF-A (HR 2.095, 95% CI 1.028-4.271, P?=?0.042) were independent negative prognosticators for DSS, MFS and RFS, respectively, in the ET group. FGFR-1 was an independent positive prognosticator for DSS (HR?=?0.243, 95% CI?=?0.095-0.618, P?=?0.003) in the VR group.

Conclusions

Angiogenic molecules from the PDGF and VEGF families have prognostic impact in soft-tissue sarcomas arising in the ET, but not in VR locations. In the latter histological grade and resection margins are the most important prognostic factors.  相似文献   
8.
9.
The causal relationship between lower respiratory tract infections (LRIs) in early life and reduced lung function later in childhood is unsettled. Therefore, we assessed whether LRIs the first 2 yr of life influenced lung function development from birth to school age. In the prospective Oslo birth cohort, ‘the Environment and Childhood Asthma (ECA) study’ lung function was measured at birth in 802 infants by tidal flow volume loops and in 664 infants by passive respiratory mechanics and half yearly questionnaires, including LRI questions, were completed until 2 yr of age. The present study includes 607 children with information about LRIs the first 2 yr of life and successfully forced expiratory flow (FEF) volume measurements at the 10‐yr follow‐up assessment. At 10 yr of age, FEF at 50% of forced vital capacity (FEF50) (mean 95% confidence interval) was reduced in children with at least one bronchiolitis (85.0, 80.6–89.5, p = 0.020) or bronchitis (86.2, 82.6–89.8, p = 0.030) or ≥3 LRIs (83.4, 78.1–88.8, p = 0.017) when compared with no LRIs (90.6, 88.8–92.5) by 2 yr of life. The effects were significant in girls only when stratifying for gender. Among girls with later bronchiolitis compliance of the respiratory system (3.64, 3.17–4.10 vs. 4.18, 3.98–4.37, p = 0.031) and the ratio of time to peak tidal expiratory flow to total expiratory time (tPTEF/tE) measured at birth was significantly reduced (0. 26, 0.23–0.29 vs. 0.32, 0.30–0.33, p = 0.005) when compared with children with no LRIs. Change in lung function from birth (by tPTEF/tE) to 10 yr of age was not significantly associated with LRIs the first 2 yr of life, and LRIs by 2 yr of life were not significantly associated with lung function at 10 yr of age in regression analyses including lung function at birth and other possible predictors of lung function at 10 yr. In our study, LRIs during the first 2 yr of life did not impair lung function development from birth until 10 yr of age.  相似文献   
10.
The aim of this study was to describe and compare bone mineral density (BMD) development in Norwegian women and men aged 25-44 years in a population-based, longitudinal study. BMD was measured twice at distal and ultradistal forearm sites by single x-ray absorptiometry in 258 women and 147 men (mean follow-up time, 6.4 (standard deviation, 0.6) years). At the distal site, a small annual gain of approximately 0.1% became a small loss beginning at age 34 years in men and age 36 years in women. At the ultradistal site, BMD change was predicted by age in women only, and bone loss started at age 38 years. A high degree of tracking of BMD measurements was observed for both sexes and both sites, r > 0.93. Depending on total BMD change, participants were grouped into "losers", "nonlosers", and "gainers", and more than 6% lost more than the smallest detectable amount of BMD: > or =3.46% at the distal site and > or =5.14% at the ultradistal site. In both sexes, bone mineral content (grams) decreased, whereas area (centimeters squared) increased significantly in "losers" compared with "gainers". This finding might represent physiologic compensation preserving bone strength. No cohort effects were observed when 1994 and 2001 measures from similar age groups were compared.  相似文献   
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