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81.
K L Dawson-Falk A M Wright B Bakker P T Pitlick D M Wilson R G Rosenfeld 《Australasian radiology》1992,36(3):204-209
Forty patients with karyotypically proven Turner syndrome were prospectively studied using magnetic resonance imaging (MRI) and echocardiography in order to determine the frequency of cardiovascular anomalies and to assess the utility of both imaging modalities as methods for cardiovascular evaluation in Turner syndrome. Cardiovascular anomalies were found in 45% of patients. A high absolute prevalence of bicuspid aortic valve (17.5%) and aortic coarctation (12.5%) were observed relative to comparable series. Of clinically significant abnormalities, three of five aortic coarctations and four of five ascending aortic dilatations were solely MRI detected and not evident at echocardiographic examination. MRI is thus seen as a valuable adjunct to echocardiography in the cardiovascular evaluation of Turner syndrome patients. The usefulness of MRI primarily relates to its ability to provide excellent visualisation of the entire thoracic aorta where a large proportion of clinically significant anomalies occur in Turner syndrome. 相似文献
82.
A case of intentional overdose with 18 'Ecstasy' tablets is described. 'Ecstasy' is a semi-synthetic hallucinogenic amphetamine and acute adverse reactions follow from the effects of sympathetic stimulation. To our knowledge this is the first reported case of massive intentional overdose reported in the literature. 相似文献
83.
Deoxyribonucleic acid amplification and hybridisation in Crohn''s disease using a chlamydial plasmid probe. 总被引:1,自引:1,他引:0
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The possibility that Crohn's disease is caused by infection with Chlamydia trachomatis was examined by probing for chlamydial plasmid deoxyribonucleic acid (DNA) in DNA extracts from Crohn's disease tissue and by means of a serological study. Gut DNA extracts were obtained from 10 patients with Crohn's disease and four control subjects and were probed with a chlamydial plasmid probe after Southern blotting. The polymerase chain reaction was also used to amplify any chlamydial plasmid DNA present in tissue DNA extracts, before Southern blotting and probing. Chlamydial proctitis control specimens were not available: gut DNA extracts mixed with traces of chlamydia plasmid served as positive controls. Using these techniques, no chlamydial plasmid DNA sequences were found in Crohn's disease tissue. An enzyme linked immunosorbent assay for C trachomatis LI was performed on 48 patients with Crohn's disease and 48 control subjects. Seropositivity was present in 14.6% of patients and 29% of control subjects and was not statistically significant (p greater than 0.05). The failure to show chlamydial DNA and the lack of serological response to chlamydia make C trachomatis infection a very unlikely factor in the pathogenesis of Crohn's disease. 相似文献
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L F Hiratzka C L Eastham J G Carter J R Moyers D R Elliott D B Doty C B Wright M L Marcus 《The Annals of thoracic surgery》1988,45(5):474-481
In normal coronary arteries, reactive hyperemic responses to a 20-second occlusion, an index of coronary reserve, usually demonstrate a peak-to-resting flow velocity ratio of 4:1 or more. Most intraoperative studies that have assessed reactive hyperemic responses in bypassed vessels have reported peak-to-resting flow velocity ratios of 2:1 or less following a 20-second occlusion. These decreased reactive hyperemic responses could be due to coronary vasodilatation after cardiopulmonary bypass or to an inadequate physiological result of the surgical procedure. In 14 patients with angiographically normal coronary arteries, the peak-to-resting flow velocity ratio following a 20-second coronary occlusion decreased significantly (p less than 0.05) from 4.4 +/- 0.2 (mean +/- standard error) before bypass to 3.0 +/- 0.3 after bypass. In a similar dog model, the peak-to-resting flow velocity ratio decreased by 36 to 52% during the first hour following one hour of cardiopulmonary bypass and cardioplegia. During the same period, left ventricular perfusion increased 21 to 30%, mean arterial pressure and coronary vascular resistance decreased, and myocardial oxygen consumption was unchanged. In a second group of dogs studied for the effects of duration (200 to 240 minutes) of anesthesia and thoracotomy alone, peak-to-resting flow velocity ratio was significantly lower. These clinical and experimental studies suggest that major coronary vasodilatation occurs early following cardiopulmonary bypass and cold cardioplegia, and may contribute to the blunted coronary reactive hyperemic responses reported during this time. Consequently, an intraoperative peak-to-resting flow velocity ratio of 3:1 for bypassed coronary arteries may represent an excellent physiological result. 相似文献
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Because of the recent rapid increase in the number of knee injuries related to racquet sports, the authors undertook a retrospective study of such injuries seen over a 5-year period at the Toronto Western Hospital Sports Medicine Institute. The 121 patients who presented over the study period with a racquet-sports-related knee injury requiring arthroscopy represented 30% of all racquet-sports related injuries seen during that period. The mean age at presentation was 32.8 years and two-thirds of the patients were men. All the major racquet sports were represented. In all, 213 lesions (7 bilateral) were seen at 128 arthroscopies, and 165 arthroscopic procedures were performed. The most common lesion was meniscal followed by chondromalacia patellae, anterior cruciate ligament tears, chondral lesions and pathologic plicae. Over 90% of the patients returned to their chosen racquet sport within 3 months of the arthroscopy and most were playing at a similar performance level to that before the initial injury. 相似文献
89.
R. Langevin PhD R. Lang PhD R. Reynolds PhD P. Wright MA D. Garrels MA V. Marchese BSc L. Handy G. Pugh PhD R. Frenzel BSc 《Sexual abuse : a journal of research and treatment》1988,1(1):13-32
Test properties of the Millon Clinical Multiaxial Inventory (MCMI) were examined in a sample of 419 sex offenders and controls in three different settings. The offender group included sexual aggressives, pedophiles, incest perpetrators and miscellaneous cases. Nineteen of the 20 scales of the MCMI had alpha reliability over 0.60 and for 13 scales it was over 0.80. The scales showed satisfactory discriminant validity from age but 9 scales showed a moderate influence of intelligence scores and education. Criminal history did not influence scale results. The scales unfortunately did show significant correlations with MMPI validity scales. Although the scales were not susceptible to naive lying, they were influenced by social desirability especially. Four factors were extracted in principal axes factor analysis that accounted for 91.2% of the total variance. The first factor explained 58.2% of the variance and was labeled general psychopathology. The other three factors suggested psychotic tendencies, extraversion and the bipolar dependency-antisocial tendencies. When the groups were compared, almost all scales significantly differentiated them. When the MMPI F-K Scale was forced to enter a stepwise discriminant analysis first, five scales still were significant; Narcissistic, Schizoid-Asocial, Alcohol Abuse, Paranoid, & Dependent-Submissive scales. The MCMI taps important dimensions in sex offenders but suffers from validity problems. 相似文献
90.
Alister Oliver Mark Wright Andrew Matson Graham Woodrow Neil King Louise Dye 《Nephrology, dialysis, transplantation》2004,19(11):2883-2885
BACKGROUND: Interdialytic weight gain (IDWG) can be reduced by lowering the dialysate sodium concentration ([Na]) in haemodialysis patients. It has been assumed that this is because thirst is reduced, although this has been difficult to prove. We compared thirst patterns in stable haemodialysis patients with high and low IDWG using a novel technique and compared the effect of low sodium dialysis (LSD) with normal sodium dialysis (NSD). METHODS: Eight patients with initial high IDWG and seven with low IDWG completed hourly visual analogue ratings of thirst using a modified palmtop computer during the dialysis day and the interdialytic day. The dialysate [Na] was progressively reduced by up to 5 mmol/l over five treatments. Dialysis continued at the lowest attained [Na] for 2 weeks and the measurements were repeated. The dialysate [Na] then returned to baseline and the process was repeated. RESULTS: Baseline interdialytic day mean thirst was higher than the dialysis day mean for the high IDWG group (49.9+/-14.0 vs 36.2+/-16.6) and higher than the low weight gain group (49.9+/-14.0 vs 34.1+/-14.6). This trend persisted on LSD, but there was a pronounced increase in post-dialysis thirst scores for both groups (high IDWG: 46+/-13 vs 30+/-21; low IDWG: 48+/-24 vs 33+/-18). The high IDWG group demonstrated lower IDWG during LSD than NSD (2.23+/-0.98 vs 2.86+/-0.38 kg; P<0.05). CONCLUSIONS: Our results indicate that patients with high IDWG experience more intense feelings of thirst on the interdialytic day. LSD reduces their IDWG, but paradoxically increases thirst in the immediate post-dialysis period. 相似文献