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51.
Jan Paul Ouwens Wim van der Bij Thomas W van der Mark Albert Geertsma Do A Piers Wim J de Boer Gerard H Ko?ter 《The Journal of heart and lung transplantation》2004,23(1):115-121
BACKGROUND: A decrease in forced expiratory volume in 1 second (FEV(1)) as a diagnostic criterion for bronchiolitis obliterans syndrome (BOS) after single lung transplantation may be influenced significantly by the presence of the native lung. To quantify and to discriminate between the relative contribution of graft and native lung to the FEV(1), we retrospectively investigated the diagnostic value of combined FEV(1) measurements and ventilation scintigraphy in pulmonary dysfunction after single lung transplantation in 11 recipients with pulmonary vascular disease, 3 with obstructive lung disease, and 3 with restrictive lung disease. METHODS: We assessed function of the native lung and the graft, and subsequently calculated an adjusted grading of BOS by correcting routine FEV(1) measurements using linear interpolation of bi-annual lung ventilation scans. RESULTS: The contribution of the native lung to the total FEV(1) was slight (median, 9%) in recipients with obstructive disease compared with recipients with vascular (38%) or restrictive lung diseases (27%). Adjusted BOS grading was not useful in patients with obstructive disease. In the other patient groups, the onset of adjusted BOS Grade 1 and standard BOS Grade 1 was at a median of 220 days (range, 127-1146 days) and 836 days (184-3065 days), respectively. CONCLUSION: Ventilation scintigraphy is a useful adjunct in the (early) diagnosis of BOS in recipients of single lung transplants who have vascular and restrictive lung diseases. 相似文献
52.
Mark R. Beauchamp Albert V. Carron Serena McCutcheon Oliver Harper 《Annals of behavioral medicine》2007,33(2):200-206
Background: A growing body of research suggests that older exercisers prefer to exercise alone rather than in group-based settings. One
limitation of these studies, however, has been that researchers have failed to take into account the age-related characteristics
of groups when asking adults about their preferences for exercise settings.Purpose: The overall purpose of this study was to examine the exercise preferences of 947 adults for involvement in standard exercise
classes populated by participants from various categories across the age spectrum.Results: The results revealed that when faced with the prospect of exercising with considerably older or younger exercisers, participants
found such an exercise context to be largely unappealing. However, in accordance with the basic tenets of self-categorization
theory, the results revealed that older and younger adults alike express a positive preference for exercising in standard
exercise classes comprised of similarly aged participants.Conclusions: The findings of this study challenge a growing call for exercise interventions for older adults to be primarily directed
at the individual-level, and suggest that group-related intervention strategies may indeed be attractive to older exercisers. 相似文献
53.
54.
Aurélie Daelemans Thierry Leloup Christine Decaesteker Albert De Mey 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》2006,40(6):335-344
Our aim was to develop and validate a new method to assess objectively and quantitatively the morphology of the nostrils after nasal or nasolabial surgery. We used digital analysis using specific mathematical algorithms to assess several geometric measurements, particularly of facial asymmetry, expressed in adimensional units. Forty-five patients with no facial anomalies (control group) were used initially to evaluate the method and to obtain variables for statistical reference. Thirty-five patients operated on for unilateral cleft lip and palate (cleft group) were then analysed and compared with the control group. Individual scores were obtained for each patient, computed, and correlated with those established by a lay panel. Statistical analysis showed good sensitivity and reliability (R>0.8). 相似文献
55.
I-Chan Huang Richard J. Willke Mark J. Atkinson William R. Lenderking Constantine Frangakis Albert W. Wu 《Quality of life research》2007,16(6):1065-1072
Background Most US studies that estimate EQ-5D index score generally apply the UK preference weights. We compared the validity of a
newly-developed US weights to the UK weights for use of EQ-5D as a measure of health-related quality of life. Methods Data were collected from a randomized clinical trial for patients with HIV (n = 1,126) in the US. Convergent validity was examined by comparing Pearson correlations of EQ-5D index scores with the MOS-HIV
Health Survey scale scores and Physical and Mental Health Summary (PHS, MHS) scores using the US and UK weights. Known-groups
validity of EQ-5D US versus UK index scores was compared using clinical variables (CD4+ cell count and HIV viral load), and
the MOS-HIV PHS and MHS. Score changes in the EQ-5D index from baseline to week 50 were examined using effect size (ES) estimates.
Results The mean EQ-5D index scores was slightly higher using US weights than UK weights (0.87 vs. 0.84, respectively). The correlation
coefficient for EQ-5D utilities using the US and UK weights was 0.98. The correlations of EQ-5D index scores with the MOS-HIV
scores were moderate and similar using the US and UK weights. The EQ-5D index scores discriminated equally well for both versions
between levels of CD4+ count, HIV viral load, and PHS and MHS scores (P < 0.05), suggesting equivalent known-groups validity. The changes in EQ-5D index scores from baseline to week 50 were similar
for both versions (ES: 0.21 vs. 0.22 for US and UK, respectively), suggesting equivalent responsiveness to score changes.
Conclusions EQ-5D index scores generated using UK and US preference weights showed equivalent psychometric properties. For assessing
treatment benefit in a single population, the use of either the UK or US weights as a measure of HRQOL will not change inferences.
However, for comparisons across US and UK populations, the choice between these two weights should be based on their relevance
to the study population. 相似文献
56.
M Lorenzato H Millart O Albert M Aurousseau 《Methods and findings in experimental and clinical pharmacology》1987,9(10):649-656
The study was performed with isolated perfused isovolumic rat hearts. After a 40 min stabilization period, the effect of 4-deoxypyridoxine (DOP) 10(-5) M was studied with 3 Glc concentrations: 0, 3.3 and 11 mM. DOP was perfused during a 20 min normoxic or anoxic period followed by 40 min of normal perfusion. During normoxia with 11 mM Glc, DOP decreased the contracture observed in the control group. With 0 mM Glc, DOP improved developed pressure and dP/dt+ without a decrease in glycogen stores. During anoxia followed by reoxygenation, a partial protection towards CK release was observed with DOP (3.3 mM Glc). Intracellular PLP levels were higher in the 11 mM Glc group than in the other groups with and without DOP, and DOP with 11 mM Glc increased PLP levels (DOP N2 vs. DOP O2). Glycogen stores increased with 11 mM Glc without DOP (O2 vs. N2), whereas they decreased with DOP without Glc (DOP N2 vs. N2). DOP could improve the yield in glycogenolysis in normoxia and might activate mitochondrial anaerobic metabolism during anoxia. 相似文献
57.
Analysis of daily self-ratings of energy for 10 patients diagnosed with seasonal affective disorder (SAD) revealed statistically significant seasonal patterns in eight patients (with all patients showing the most energy in the summer and the least energy in the winter). When weather was controlled for, the seasonal patterns in energy persisted in seven of the eight patients. In a lesser number of subjects (four), there were significant effects of weather after controlling for season; however, when the effects of weather on energy were examined separately for each season, 8 of the 10 subjects were found to be influenced by weather in at least one season. Daily sleep data showed statistically significant seasonal patterns in all 10 patients (with 6 subjects showing maximum sleep in winter and 4 in summer). As for the relationship between energy and sleep, a loss of energy appeared to predict longer sleep on that night and the next night (7 of 10 patients), whereas there was no evidence that prolonged sleep influenced energy on the following and subsequent days. 相似文献
58.
Steven G. E. Marsh Ekkehard D. Albert Walter F. Bodmer Ronald E. Bontrop Bo Dupont Henry A. Erlich Daniel E. Geraghty John A. Hansen Bernard Mach Wolfgang R. Mayr Peter Parham Effie W. Petersdorf Takehiko Sasazuki Geziena M. Th. Schreuder Jack L. Strominger Arne Svejgaard Paul I. Terasaki 《International journal of immunogenetics》2002,29(6):463-515
59.
Tony M. Keaveny Tania P. Pinilla R. Paul Crawford David L. Kopperdahl Albert Lou 《Journal of orthopaedic research》1997,15(1):101-110
We sought to quantify the systematic and random errors associated with-artifacts in the platens compression test for trabecular bone. Our hypothesis was that while errors may depend on anatomic site, they do not depend on apparent density and therefore have substantial random components. Trabecular bone specimens were first tested nondestructively using newly developed accurate protocols and then were tested again using the platens compression test. Percentage differences in modulus between the techniques (bovine) proximal tibia [n = 18] and humerus [n = 17] and human lumbar spine, [n = 9] were in the range of 4-86%. These differences did not depend on anatomic site (p = 0.21) and were only weakly dependent on apparent density and specimen aspect ratio (r2 < 0.10). The mean percentage difference in modulus was 32.6% representing the systematic component of the end-artifact error. Neglecting the minor variations explained by density and specimen size (approximately 10%), an upper bound on the random error from end-artifacts in this experiment was taken as the SD of the modulus difference (±18.2%). Based on a synthesis of data taken from this study and from the literature, we concluded that the systematic underestimation error in the platens compression test can be only approximated and is in the range of 20-40%; the substantial random error (±12.5%) confounds correction, particularly when the sample size is small. These errors should be considered when interpreting results from the platens test, and more accurate testing techniques should be used when such errors are not acceptable. 相似文献
60.
Gastric accommodation and emptying in evaluation of patients with upper gastrointestinal symptoms. 总被引:7,自引:0,他引:7
Albert J Bredenoord Heather J Chial Michael Camilleri Brian P Mullan Joseph A Murray 《Clinical gastroenterology and hepatology》2003,1(4):264-272
BACKGROUND & AIMS: Endoscopy-negative dyspepsia is a common symptom that often is difficult to define in pathophysiologic terms. The aim of this study was to assess the frequency of disordered gastric accommodation and emptying in patients referred with unexplained upper gastrointestinal symptoms. METHODS: A computerized diagnostic index was used to identify all patients, 18-70 years old, who underwent single-photon emission computed tomography (SPECT) to assess gastric accommodation at Mayo Clinic Rochester over a 3-year period. Demographics, clinical features, and results of diagnostic testing, including scintigraphic gastric emptying, were extracted from the electronic record. RESULTS: A total of 214 patients were identified; the primary clinical diagnoses were functional dyspepsia, postfundoplication syndromes, rumination syndrome, and diabetic dyspepsia. Gastric accommodation was impaired in 43% of the whole group: 47% of functional dyspepsia, 44% of postfundoplication syndromes, and 33% of diabetic dyspepsia. Delayed gastric emptying was most prevalent in diabetic dyspepsia, and was accelerated in postfundoplication syndromes groups. Thirty-seven percent of patients had abnormal gastric emptying. The highest prevalence of delayed gastric emptying was in the diabetic dyspepsia and accelerated gastric emptying in postfundoplication syndromes groups. Twenty-five percent of patients with normal gastric emptying had impaired accommodation. Upper-gastrointestinal symptoms were not different in groups based on gastric accommodation or emptying results. CONCLUSIONS: Impaired gastric accommodation is common in patients with unexplained dyspepsia. Symptoms alone cannot predict physiologic disturbances. These noninvasive tests identify single or combined pathophysiologic disturbances and may help to identify subgroups of patients as candidates for more selective pharmacotherapy in the future. 相似文献