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41.
In this prospective, case-control study, femoral neck diameter, cross-sectional moment of inertia, or section modulus was an independent predictor of hip fracture risk after adjustment for BMD. However, the contribution of each of these indices to hip fracture prediction was modest in the presence of BMD. INTRODUCTION: The relative contribution of measures of hip strength to hip fracture prediction is unclear. This study was designed to characterize the association between hip strength indices and hip fracture risk in relation to BMD in elderly men and women. MATERIALS AND METHODS: Seventy-one women and 25 men>or=60 years of age, who sustained a hip fracture during the study period of 1989-2003, were selected from the prospective, population-based Dubbo Osteoporosis Epidemiology Study. These fracture cases were randomly matched for age and sex in a 1:2 ratio with nonfracture individuals. BMD at the femoral neck was measured before the fracture event by DXA (Lunar DPX-L). Hip strength indices, including femoral neck diameter (FND), cross-sectional moment of inertia (CSMI), and section modulus (Z), were estimated by reanalysis of the image files using hip strength analysis software. RESULTS: In women, after adjustment for BMD, increased risk of hip fracture was associated with smaller FND (OR, 1.6; 95% CI, 1.0, 2.7), lower CSMI (OR, 1.8; 95% CI, 1.0, 3.2), or Z (OR, 1.6; 95% CI, 1.1, 5.1). In men, none of these hip strength indices were significant predictors of fracture risk. However, using the results in women as a prior distribution, it was estimated that the BMD-adjusted OR for FND (OR, 1.5; 95% CI, 1.0, 2.3), CSMI (OR, 1.6; 95% CI, 1.0, 2.5), or Z (OR, 2.3; 95% CI, 1.4, 3.9) was each significantly associated with hip fracture risk in men. In the logistic regression model, BMD alone accounted for 32% and 16% of the variance of fracture liability in women and men, respectively. The addition of FND, CSMI, or Z to the model increased the respective variance proportion to 34% and 19%. CONCLUSIONS: These data suggest that smaller FND and lower CSMI or Z is an independent risk factor for hip fracture in both women and men. However, the contribution of these measures to hip fracture prediction over and above BMD is likely modest.  相似文献   
42.
All patients in hospital care and primary health care in the county of Västerbotten, Sweden (n = 5158) were asked to express their level of satisfaction with the quality of care. The study was carried out on one specific day. All personnel on duty that day (n = 2824) were also included and asked to give their interpretations of their patients' experiences. A questionnaire containing positive and negative statements concerning both the relationship and the task aspects of care was used. The results showed that the youngest and oldest patients expressed the highest degree of satisfaction, while young and middle-aged patients expressed a more restrained view. The least satisfactory aspects concerned the opportunities to express criticism and the possibilities of receiving information about access to help outside the health care organization. The personnel's responses agreed with those of the patients, but fewer personnel thought that their patients were satisfied than was in fact the case.  相似文献   
43.
Torture can be defined as the deliberate or systematic infliction of physical or mental suffering to force another person to yield information, as a punishment or to destroy a person's identity. The aim of the physiotherapy treatment for persons who have undergone torture is to relieve or reduce pain, correct musculoskeletal dysfunctions, teach the client to cope with pain, and regain body awareness. A good interaction and communication with each refugee is needed to optimize the treatment. The aim of this study was to identify factors important for a good interaction between physiotherapist (PT) and the patient among PTs specialising in refugees who have been tortured. A qualitative multiple case study was done. Ten physiotherapists working within the Red Cross, psychiatry or primary health care, who held positions specialising in treating persons who have undergone torture were interviewed. The interviews were analysed with content analysis. The results showed that the factors important for a good interaction could be summarised into two themes; prerequisites for a good interaction and interaction factors. Five prerequisites for a good interaction with persons who have undergone torture were found: personal characteristics, professional and therapeutic competence and support, language factors, time, and frames. Five factors in the interaction situation were important for a good interaction: cultural factors, treatments tailored to the patient's needs, to develop confidence and trust, religious factors, and capacity to handle negative emotions. All these factors have to be considered to improve the interaction between PTs and persons who have undergone torture.  相似文献   
44.
We have investigated whether side chain-hydroxylated cholesterol species are important for elimination of cholesterol from the brain. Plasma concentrations of 24-hydroxycholesterol (24-OH-Chol) in the internal jugular vein and the brachial artery in healthy volunteers were consistent with a net flux of this steroid from the brain into the circulation, corresponding to elimination of approximately 4 mg cholesterol during a 24-h period in adults. Results of experiments with rats exposed to 18O2 were also consistent with a flux of 24-OH-Chol from the brain into the circulation. No other oxysterol measured showed a similar behavior as 24-OH-Chol. These results and the finding that the concentration of 24-OH-Chol was 30- to 1500-fold higher in the brain than in any other organ except the adrenals indicate that the major part of 24-OH-Chol present in the circulation originates from the brain. Both the 24-OH-Chol present in the brain and in the circulation were the 24S-stereoisomer. In contrast to other oxysterols, levels of plasma 24-OH-Chol were found to be markedly dependent upon age. The ratio between 24-OH-Chol and cholesterol in plasma was approximately 5 times higher during the first decade of life than during the sixth decade. There was a high correlation between levels of 24-OH-Chol in plasma and cerebrospinal fluid. It is suggested that the flux of 24-OH-Chol from the brain is important for cholesterol homeostasis in this organ.  相似文献   
45.
To determine whether arm lactate release during arm exercise is related to the training status of the arms, seven arm-trained athletes were studied during 30 min of continuous arm exercise (AE) or leg exercise (LE) of increasing intensities corresponding to 30%, 50%, and 80% of peak VO2 during AE and LE respectively. Blood vessels were catheterized for determination of regional blood flows and substrate exchanges. The respiratory exchange ratio was higher during AE than LE (P less than 0.01). The arteriovenous oxygen difference, [(A-V)O2], for the leg during LE was 11-19% higher than the (A-V)O2 for the arm during AE (P less than 0.01). At the highest intensity the (A-V)O2 was 170 +/- 6 ml O2l-1 during LE, vs. 143 +/- 9 during AE (P less than 0.01). Arm blood flow in relation to limb volume was 56-95% higher during AE (P less than 0.05). Arterial lactate concentrations were 27-60% higher during AE (P less than 0.01) and lactate release from the exercising limb was 2-4 times higher (P less than 0.05) during AE compared to LE. Adrenaline and noradrenaline rose 6- and 21-fold, respectively, during AE and did not differ from corresponding LE values. During AE the (A-V)O2 difference across the arm, arterial lactate concentration, and arm lactate release were of the same magnitude in arm-trained and relatively less arm-trained subjects. Lactate release in relation to O2 uptake by the exercising limb was 7-37% lower during AE in arm-trained subjects compared to AE in arm-untrained subjects but was 3-6 times higher than the corresponding relation during LE (P less than 0.01). We conclude that AE is associated with a larger lactate release compared to LE. This difference is only to a minor extent influenced by intense training of the arms. The high arm vs. leg lactate release appears to be associated with differences in regional circulatory adaptation by the exercising limb.  相似文献   
46.
Summary: Purpose: To determine if, and how, epileptiform EEG discharges in children were influenced by physical exercise.
Methods: Twenty-six children with intractable partial and generalized epilepsy exercised during video-telemetry recording, aiming at exhaustion after ∼10 min.
Results: During the exercise, epileptiform discharges decreased in 20 of 26 children (17 children had at least 25% reduction) and showed a rebound increase after the exercise (17 of 26 children) compared to baseline conditions. This exercise-induced reduction in epileptiform discharges reached statistical significance only in the 16 patients with localization-related epilepsy. Five patients showed an atypical EEG response to exercise with either unchanged or increased epileptiform activity while exercising. As compared to the other patients, these 5 children had experienced frequent clinical seizures during or immediately after exercise in their leisure time.
Conclusions: In the majority of the tested children, epileptiform EEG discharges decreased during exercise. "Exercise-EEG" may be a helpful diagnostic tool to identify patients who are disposed to have exercise-induced seizures.  相似文献   
47.
OBJECTIVE: Compare 5-year-old dental arch relationships of patients from three centers with differing primary protocols. DESIGN: Retrospective study of treatment outcomes using blinded evaluation of dental study casts. SETTING: Three major cleft-craniofacial centers; one (center A) is a free-standing institution, and two (centers B and C) are university hospitals. PATIENTS: 118 (A = 41; B = 33; C = 44) consecutively treated 5-year-old patients with complete, nonsyndromic unilateral cleft lip and palate. INTERVENTIONS: Centers A and C completed primary repair without presurgical orthopedics by 18 months (center A in three surgeries and center C in two surgeries). Center B used passive presurgical orthopedics with lip/soft palate repair at 6 months and gingivo-alveoloplasty/hard palate repair at 18 to 36 months. MAIN OUTCOME MEASURE: Averaged ratings of dental casts using the 5-year yardstick were computed for each patient. The Wilcoxon two-sample test was used to compare means; a chi-square test was used to compare distributions. RESULTS: Intra- and interexaminer reliability tests showed excellent reliability (>.90). Mean scores were not significantly different. Distribution of scores differed significantly. Center A had the highest percentage of good scores and the lowest percentage of poor scores (72% versus 6.5%), followed by center B (63% versus 6.6%) and center C (59% versus 16.3%). CONCLUSIONS: Centers A and B had comparable scores and completely different protocols in surgical technique, timing, sequencing, and nonuse/use of appliances. Center C's results were slightly lower than those of 1 and 3, but the center had the protocol with the least burden of treatment (only two surgeries, without use of appliances).  相似文献   
48.
49.
Summary. To investigate the effects and elimination of endothelin-1 in humans, an intravenous infusion of endothelin-1 (ET-1) (4 pmol kg-1 min-1 for 20 min) was given to 10 healthy volunteers. Arterial plasma endothelin-1 like immunoreactivity (ET-1-LI) increased eleven-fold. The fractional extraction of ET-l-LI was 41% and 30% across the pulmonary and skeletal muscle vascular beds, respectively. The lung eliminated almost half of the administered ET-1. No fractional extraction was found in the cerebral circulation. The pulmonary oxygen uptake (VO2)was increased slightly by endothelin-1. Across both the cerebral and skeletal muscle vascular beds the arterio-venous oxygen difference decreased (P < 0–05), suggesting vasodilation, the effect lasting up to 1 h after the end of endothelin-1 infusion in the cerebral circulation. Arterial-pulmonary artery oxygen difference increased by 20%. ET-1 infusion led to a decrease in heart rate (10%), cardiac output (14%) and stroke volume (8%) (all with P < 0'05) as well as a 7% increase in mean arterial blood pressure. Pulmonary and systemic vascular resistance increased by 67% and 25%, respectively (P < 0–05). These results demonstrate the regional differences in the removal of circulating endothelin-1, the lung being mainly responsible for the plasma elimination. Endothelin-1 seems to exert both vasoconstrictive and vasodi-latory actions in humans, probably depending on differences in receptor populations and endothelium configuration in various vascular beds.  相似文献   
50.
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