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21.
OBJECTIVES: We conduct a longitudinal non-invasive study of changes in urinary bladder contractility secondary to benign prostatic enlargement. In that study, the prostate volume is estimated by transabdominal ultrasonography. The accuracy of those measurements was verified by comparison of transabdominal to transrectal stepwise planimetric ultrasonography as the gold standard. Also, two different transabdominal devices used were compared, and the influence of different operators was studied. MATERIALS & METHODS: Two series of measurements in 100 patients each were done. In the first series, transabdominal and transrectal sonography were pairwise compared in each patient. In the second series, transabdominal measurements were done with two devices (a hospital Aloka SSD-1700 and a portable Aloka SSD-900). Transrectal scannings were done by three investigators whilst all transabdominal scannings were done by one. Regression graphs, ratio plots and statistical analyses of the data quantified the reproducibility of different methods, observers and device types. RESULTS: In the transrectal-transabdominal series of prostate volume measurements (in cm3), the Pearson correlation coefficient was 0.84 (p < 0.001), the mean of the means was 51.8 +/- 23.0 (mean +/- S.D.), and the mean of the differences was 1.0 +/- 1.4. In the series with two devices, the Pearson correlation coefficient was 0.73 (p < 0.001), the mean of the means was 31.0 +/- 10.9, and the mean of the differences was 1.0 +/- 1.3. CONCLUSION: No statistically significant differences were found between the transabdominal- transrectal ultrasonography, two different transabdominal devices nor between different observers. However, for those using these measurements in everyday clinical practice, it is worth to point out that in our data a transabdominal scan and a transrectal scan in the same patient, on the same day, differed more than 30% in one fourth of the patients and that two transabdominal scans in the same patient (with two different devices, on two different days) differed more than 30% in every fifth patient.  相似文献   
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STUDY OBJECTIVES: To establish the value of electrical impedance tomography (EIT) in assessing pulmonary edema in noncardiogenic acute respiratory failure (ARF), as compared to the thermal dye double indicator dilution technique (TDD). DESIGN: Prospective clinical study. SETTING: ICU of a general hospital. PATIENTS: Fourteen ARF patients. INTERVENTIONS: In order to use the TDD to determine the amount of extravascular lung water (EVLW), a fiberoptic catheter was placed in the femoral artery. Measurements and main results: Fourteen consecutive ARF patients receiving mechanical ventilation were measured by EIT and TDD. EIT visualizes the impedance changes caused by the ventilation in two-dimensional image planes. An impedance ratio (IR) of the ventilation-induced impedance changes of a posterior and an anterior part of the lungs was used to indicate the amount of EVLW. For the 29 measurements in 14 patients, a significant correlation between EIT and TDD (r = 0. 85; p < 0.001) was found. The EIT reproducibility was good. The diagnostic value of the method was tested by receiver operator characteristic analysis, with 10 mL/kg of EVLW considered as the upper limit of normal. At a cutoff level of the IR of 0.64, the IR had a sensitivity of 93%, a specificity of 87%, and a positive predictive value of 87% for a supranormal amount of EVLW. Follow-up measurements were performed in 11 patients. A significant correlation was found between the changes in EVLW measured with EIT and TDD (r = 0.85; p < 0.005). CONCLUSION: We conclude that EIT is a noninvasive technique for reasonably estimating the amount of EVLW in noncardiogenic ARF.  相似文献   
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The value of magnetic resonance imaging (MRI) in lumbosacral spinal dysraphism is reviewed. Althoigh some technical problems still remain to be overcome, it is obvious tha MRI is the examination of choice for the preoperative assessment of these congenital disesses.  相似文献   
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There appear to be contradicting theories and empirical findings on the association between adolescent Social Anxiety Disorder (SAD) symptoms and cannabis use, suggesting potential risk as well as protective pathways. The aim of this six-year longitudinal study was to further examine associations between SAD symptoms and cannabis use over time in adolescents from the general population, specifically focusing on the potential role that adolescents’ involvement with their peers may have in these associations. Participants were 497 Dutch adolescents (57 % boys; M age = 13.03 at T1), who completed annual self-report questionnaires for 6 successive years. Cross-lagged panel analysis suggested that adolescent SAD symptoms were associated with less peer involvement 1 year later. Less adolescent peer involvement was in turn associated with lower probabilities of cannabis use as well as lower frequency of cannabis use 1 year later. Most importantly, results suggested significant longitudinal indirect paths from adolescent SAD symptoms to cannabis use via adolescents’ peer involvement. Overall, these results provide support for a protective function of SAD symptoms in association with cannabis use in adolescents from the general population. This association is partially explained by less peer involvement (suggesting increased social isolation) for those adolescents with higher levels of SAD symptoms. Future research should aim to gain more insight into the exact nature of the relationship between anxiety and cannabis use in adolescents from the general population, especially regarding potential risk and protective processes that may explain this relationship.  相似文献   
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Peritonitis is a frequent complication of peritoneal dialysis (PD) in children as well in adults. Data on PD and peritonitis in pediatric patients are very scarce in developing countries. A retrospective cohort study was performed between 2000 and 2008 with the aim to evaluate PD treatment and peritonitis epidemiology in pediatric patients in South Africa and identify risk factors for peritonitis. Baseline characteristics and potential risk factors of peritonitis were recorded, including housing, socio-economic circumstances, distance to PD center, type of PD, mode of catheter placement, race, presence of gastrostomy tube, weight, and height. Outcome indices for peritonitis were peritonitis rate, time to first peritonitis, and number of peritonitis-free patients. The patient cohort comprised 67 patients who were on PD for a total of 544 months. The total number of peritonitis episodes was 129. Median peritonitis rate was one episode every 4.3 patient months (2.8 episodes/patient-year, range 0–21.2). Median time to first infection was 2.03 months (range 0.1–21.5 months), and 28.4% of patients remained free from peritonitis. Patients with good housing and good socio-economic circumstances had a significantly lower peritonitis rate and a longer time to first peritonitis episode. Peritonitis rate was high in this cohort, compared to numbers reported for the developed world; the characteristics of causative organisms are comparable. The most important risk factors for the development of peritonitis were poor housing and poor socio-economic circumstances. More intensive counseling may be beneficial, but improvement of general socio-economic circumstances will have the greatest influence on PD success.  相似文献   
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In this study examination is given to the psychometric properties of the Italian version of the Screen for Child Anxiety Related Emotional Disorders (SCARED) in a large community sample of adolescents. Additionally, a comparison was made between the anxiety scores of this Italian adolescent cohort (N = 1975) and a comparative Dutch adolescent cohort (N = 1115).Findings revealed that a five-factor structure of the SCARED applied not only to the Italian adolescents from the general community, but also to boys and girls, and to early and middle adolescents. Moreover, sex and age differences on anxiety scores within the Italian sample were found to be consistent with previous studies of adolescent anxiety disorders. Finally, Italian adolescents reported higher anxiety scores than their Dutch peers.Findings of this study highlight that the SCARED is a valid screening instrument to rate anxiety symptoms of Italian adolescents.  相似文献   
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Although the stability and changeability of personality has long been debated, many studies now agree that personality changes over the life course. Although the changes in rank-order and mean-level stability are well established, the stability in personality type membership during adolescence is not yet clear. Little research has been conducted on the associations between change in personality type membership and anxiety. A total of 827 adolescents (10-20 years) completed personality and anxiety questionnaires on 2 waves of the CONflict And Management Of RElationships study (CONAMORE). We found that the stability in personality type membership was moderate. The change from undercontroller to overcontroller was the most frequently occurring change. Furthermore, the stability in type membership was related to stability in anxiety level and change in type membership was related to anxiety change. More specifically, the resilient-overcontroller group demonstrated an increase in anxiety level, whereas the overcontroller-resilient group demonstrated a decrease.  相似文献   
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