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排序方式: 共有1315条查询结果,搜索用时 15 毫秒
41.
SL Stuckey EJ Gilford PJ Smith M Kean 《Journal of Medical Imaging and Radiation Oncology》1995,39(4):350-355
This preliminary study was designed to investigate the ability of multiple axial volume three-dimensional fourier transform (3DFT) time-of-flight (TOF) magnetic resonance angiography (MRA) to depict the carotid bifurcation in the early post-carotid endarterectomy period. Five patients underwent intra-operative digital subtraction angiography (DSA) and carotid MRA within 5 days of carotid endarterectomy. An axial volume fast imaging in steady-state precession (FISP) gradient-echo 3DFT TOF carotid MRA technique in this limited series appeared to display accurately the surgically significant abnormalities at the carotid bifurcation after endarterectomy. However, in normal or near-normal intra-operative DSA studies, overestimation of internal carotid artery stenoses was encountered. Postoperative MRA demonstrates potential as a useful non-invasive investigation after carotid endarterectomy but should be interpreted with caution until larger studies become available. 相似文献
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Stef PJ Kremers Gert-Jan de Bruijn Tommy LS Visscher Willem van Mechelen Nanne K de Vries Johannes Brug 《The international journal of behavioral nutrition and physical activity》2006,3(1):9
Background
Studies on the impact of the 'obesogenic' environment have often used non-theoretical approaches. In this journal's debate and in other papers authors have argued the necessity of formulating conceptual models for differentiating the causal role of environmental influences on behavior. 相似文献44.
A Kr?mer B Schultheis J Bergmann A Willer U Hegenbart A D Ho H Goldschmidt R Hehlmann 《Leukemia》2002,16(9):1844-1851
The retinoblastoma protein (pRb), p16(INK4A), D-type cyclins, and their partners cyclin-dependent kinase (CDK) 4 and 6 constitute a G(1) regulatory pathway commonly targeted in tumorigenesis. Several malignancies show a reciprocal correlation between genetic alterations of single members of the pRb pathway. Therefore, we determined the frequency of Rb deletions and cyclin D1 alterations by fluorescence in situ hybridization as well as 5' CpG island hypermethylation of the p16(INK4A)gene using methylation-specific polymerase chain reaction in bone marrow mononuclear cells from 82 individuals with plasma cell disorders. Alterations in at least one of the components of the pathway were found in 75%. Cyclin D1 translocations or amplifications were detected in 14/82 (17.1%), Rb deletions at 13q14 in 23/82 (28%) of the cases, including three (3.6%) homozygous deletions. p16(INK4A) was hypermethylated in 33/57 (57.9%) of the samples. Further analysis revealed a highly significant correlation between cyclin D1 alterations and extramedullar or leukemic myeloma manifestations (P = 0.014; Fisher's test). Whereas Rb deletions seemed to occur alternatively to cyclin D1 alterations, no reciprocal correlation was found between p16(INK4A) hypermethylations and cyclin D1 or Rb locus aberrations. Cyclin D1 locus alterations and Rb deletions were associated with a significantly worse prognosis whereas p16(INK4A) hypermethylation had no impact on survival. We conclude that cyclin D1 and Rb aberrations seem to occur as alternative events in plasma cell malignancies and contribute to clinical course and prognosis. In contrast, although p16(INK4A) hypermethylation is frequent, inactivation of p16(INK4A) seems not to be involved in the pathogenesis of plasma cell disorders. 相似文献
45.
Long-term results of the lateral tunnel Fontan operation 总被引:11,自引:0,他引:11
Stamm C Friehs I Mayer JE Zurakowski D Triedman JK Moran AM Walsh EP Lock JE Jonas RA Del Nido PJ 《The Journal of thoracic and cardiovascular surgery》2001,121(1):28-41
OBJECTIVES: Completion of a total cavopulmonary anastomosis with an intra-atrial lateral tunnel is known to yield good early and midterm results. In this study, we sought to determine the long-term outcome (10 years) after a lateral tunnel Fontan procedure. METHODS: Between October 1987 and December 1991, 220 patients (aged 11 months to 32 years) with a wide range of underlying diagnoses underwent a fenestrated or nonfenestrated lateral tunnel Fontan procedure at our institution. Current follow-up information was available for 196 patients (94%, mean follow-up = 10.2 +/- 0.6 years). Risk factor analysis included patient-related and procedure-related variables, with death, failure, and bradyarrhythmia or tachyarrhythmia as outcome parameters. RESULTS: There were 12 early deaths (<30 days or hospital death), 7 late deaths, 4 successful takedown operations, and 4 heart transplantations. Kaplan-Meier estimated survival was 93% at 5 years and 91% at 10 years, and freedom from failure was 90% at 5 years and 87% at 10 years. Freedom from new supraventricular tachyarrhythmia was 96% at 5 years and 91% at 10 years; freedom from new bradyarrhythmia was 88% at 5 years and 79% at 10 years. Three patients had evidence of protein-losing enteropathy. Multivariable risk factors for development of supraventricular tachyarrhythmia included heterotaxy syndrome, atrioventricular valve abnormalities, and preoperative bradyarrhythmia. Risk factors for bradyarrhythmia included systemic venous anomalies. The sole risk factor for late failure was a previous coarctation repair. CONCLUSION: The lateral tunnel Fontan procedure results in excellent long-term outcome even when used in patients with diverse anatomic diagnoses. The incidence of atrial tachyarrhythmia is low and mainly depends on the underlying cardiac morphology and preoperative arrhythmia. The good long-term outcome after an intracardiac lateral tunnel Fontan procedure should serve as a basis for comparison with other surgical alternatives. 相似文献
46.
Marijke Boorsma Hein PJ van Hout Dinnus H Frijters Miel W Ribbe Giel Nijpels 《BMC health services research》2008,8(1):143
Background
The objective of this article is to describe the design of a study to evaluate the clinical and economic effects of a Disease Management model on functional health, quality of care and quality of life of persons living in homes for the elderly. 相似文献47.
NK Thalange PJ Foster MS Gill DA Price PE Clayton 《Archives of disease in childhood》1996,75(5):427-431
Overheating may cause terminal apnoea and cot death. Rectal temperature and breathing patterns were examined in normal infants at home during the first 6 months of life. Twenty one infants had continuous overnight rectal temperature and breathing recordings for 429 nights (mean 20.4 nights, range 7-30) spaced over the first six months of life. Periods when breathing was 'regular' were directly marked on single night records. Sleep state was determined from respiratory variables. 'Regular' breathing was a reliable marker of 'quiet' sleep (specificity 93%). The duration of 'quiet' sleep increased from 6 to 22 minutes from two weeks to three months of age and then remained static, as did the proportion of sleep spent in the quiet phase (9% to 34%). Rectal temperature fell during 66% of quiet sleep and usually rose during rapid eye movement (REM) sleep. The drop in rectal temperature was maximal at the start of quiet sleep, whereas the maximum rise during REM sleep was reached after 10 to 15 minutes. Oscillations in rectal temperature are associated with changes in sleep and breathing state. The maturation of rectal temperature patterns during the first six months of life are closely related to a maturation of sleep state and breathing patterns. 相似文献
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DI Wilson SB Britton C McKeown D Kelly IE Cross S Strobel PJ Scambler 《Archives of disease in childhood》1993,68(2):187-189
A boy with the dysmorphic features of Noonan's syndrome and pulmonary valve stenosis who had evidence of hypoparathyroidism and abnormal T lymphocyte numbers in the neonatal period is reported. He had a normal karyotype but molecular analysis revealed a submicroscopic deletion within chromosome 22q11, the region deleted in DiGeorge syndrome. Thus this child has both Noonan's syndrome and DiGeorge syndrome; 22q11 is a candidate region for a gene defective in Noonan's syndrome. 相似文献