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991.
In order to be empowered in different situations related to dialysis care, patients need knowledge. This study describes the knowledge expectations of patients on dialysis treatment (n = 47) and selected background variables. The results indicated that patients expressed moderate knowledge expectations. Most important were the biophysiological, functional, and ethical dimensions of knowledge. The least important were the social and experiential dimensions of knowledge. Patients' age, employment status, dialysis modality, and length of dialysis were positively correlated with knowledge expectations.  相似文献   
992.
Between 1989 and 1995, blood surveys were performed for Wuchereria bancrofti infection in several barracks of the Brazilian army in the metropolitan Recife region. For initial screening, 60 microliters of capillary blood were examined for microfilaria. All men who tested positive had microfilaria quantified by filtration of venous blood through a polycarbonate membrane. Of 23,773 men screened, 585 (2.5%) had microfilaria (mf). Microfilarial density ranged from < 1-8706 mf/ml of blood. Thirteen individuals had ultra-low microfilarial densities (1 mf/11 ml of blood). Characterization of 174 autochthonous cases made it possible to map 8 new districts in 4 cities within metropolitan Recife region where transmission of W. bancrofti was previously unknown. Routine screening of soldiers in the military may provide important surveillance data for national programmes to eliminate transmission of W. bancrofti.  相似文献   
993.
AIMS: To examine the correlation between the Fagerstr?m Test for Nicotine Dependence (FTND) score and smoking prevalence across countries. DESIGN: Cross-sectional study. SETTING: Fifteen studies from 13 countries with FTND score data. PARTICIPANTS: Samples of smokers were identified through systematic literature searches, web queries and colleagues. Smokers were considered representative of their country's smoking population if they were drawn from population-based sources, were not seeking smoking cessation treatment and did not have significant comorbidities. Smoking prevalence data were derived from the study itself or the country's population rate of daily smoking for the study year. MEASUREMENTS: A Pearson correlation coefficient was used to examine the direction and magnitude of the correlation between FTND score and smoking prevalence across countries. FINDINGS: FTND scores ranged from 2.8 to 4.6. Smokers in Germany and Norway had the lowest FTND scores, while smokers in Sweden and the United States had the highest FTND scores. The prevalence of daily smoking in these countries was very different: 37% and 30% in Germany and Norway, 19% and 16% in the United States and Sweden, respectively. An inverse correlation towards higher FTND scores in countries with lower smoking prevalence was found (r=-0.73, P=0.001). Current smokers had higher FTND scores than former smokers. CONCLUSIONS: The significant inverse correlation between FTND score and smoking prevalence across countries and higher FTND score among current smokers supports the idea that remaining smokers may be hardening. Less dependent smokers may quit more easily and remaining dependent smokers may need more intensive treatment.  相似文献   
994.
A morphometric study was undertaken to quantitate vessel numbers in uterine biopsies from a control group of patients, patients with dysfunctional uterine bleeding and patients taking low dose norethisterone or levonorgestrel. Vessels were counted at the endometrial/myometrial junction and in the functional endometrium just below the surface epithelium. The number of arteries at the endometrial/myometrial junction was found to be decreased in patients taking norethisterone and levonorgestrel. An increase was found in the total number of veins and in the number of dilated veins in the functional endometrium of the progestogen-treated specimens. Dilated veins were frequently found close to the endometrial surface and it is possible that they may be the major cause of the irregular bleeding associated with low dose oral progestogens.  相似文献   
995.
996.
The aim of this study was to test the hypothesis that the addition of continuous or milled GdAlO3/Al2O3 fibers to a dental porcelain increases its mechanical properties. Porcelain bars without reinforcement (control) were compared to those reinforced with long fibers (30 vol%). Also, disk specimens reinforced with milled fibers were produced by adding 0 (control), 5 or 10 vol% of particles. The reinforcement with continuous fibers resulted in significant increase in the uniaxial flexural strength from 91.5 to 217.4 MPa. The addition of varied amounts of milled fibers to the porcelain did not significantly affect its biaxial flexural strength compared to the control group. SEM analysis showed that the interface between the continuous fiber and the porcelain was free of defects. On the other hand, it was possible to note the presence of cracks surrounding the milled fiber/porcelain interface. In conclusion, the reinforcement of the porcelain with continuous fibers resulted in an efficient mechanism to increase its mechanical properties; however the addition of milled fibers had no significant effect on the material because the porcelain was not able to wet the ceramic particles during the firing cycle.  相似文献   
997.

Background  

Assessment of sensorimotor function is useful for classification and treatment evaluation of neck pain disorders. Several studies have investigated various aspects of cervical motor functions. Most of these have involved slow or self-paced movements, while few have investigated fast cervical movements. Moreover, the reliability of assessment of fast cervical axial rotation has, to our knowledge, not been evaluated before.  相似文献   
998.
999.
We examined the distribution and density of N-methyl-D-aspartate (NMDA) displaceable L-[3H]glutamate binding sites in human hippocampal samples obtained postmortem from Alzheimer's disease (AD) patients and from age-matched controls. Binding to NMDA receptors was stable for at least 72 h postmortem, and the pharmacological profile corresponded to that described using electrophysiology. NMDA receptors were concentrated in the terminal fields of major hippocampal pathways including the perforant path, Schaffer collaterals and the hippocampal output to the subiculum, all of which are proposed to use an excitatory amino acid transmitter. Little if any change in hippocampal receptor density was observed in AD patients compared to age-matched controls except in one case where major hippocampal cell loss occurred. The distribution of NMDA receptors did, however, correspond to the predilection for neuritic plaques and neurofibrillary tangles in hippocampal subfields.  相似文献   
1000.
This study was undertaken to evaluate the acute effects of single low doses of melatonin given to healthy volunteers in the evening. Six healthy male volunteers (age range 22-24 years) participated in this study, after signing an informed consent form. They received in a double-blind fashion placebo or 0.3 or 1.0 mg melatonin at three fixed times: 18:00, 20:00, and 21:00 hr. Polysomnographic recordings began immediately thereafter, with their being allowed to sleep. Prior to each experimental session and in the following morning, subjects completed a sleep quality questionnaire, the Profile of Mood States, the Stanford Sleepiness Scale, and underwent a visual reaction test. Significant decrease on sleep latencies was found following melatonin treatment at 18:00 and 20:00 hr. In addition, melatonin tended to improve sleep efficiency and to reduce intermittent wakefulness. However, at 21:00 hr, 0.3 mg melatonin increased latency to sleep onset and 1.0 mg melatonin had no effect on sleep variables. Furthermore, melatonin given at different times did not alter subjective sleepiness, mood, and reaction time in the following morning. The results from the present study support the notion that administration of low doses of melatonin, mimicking the nocturnal physiological concentration of this hormone may exert immediate sleep-inducing effects.  相似文献   
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