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排序方式: 共有10000条查询结果,搜索用时 109 毫秒
211.
M. A. Martín J. C. Rubio R. A. Wevers B. G. M. Van Engelen G. C. H. Steenbergen O. P. Van Diggelen M. De Visser C. De Die-Smulders A. Blázquez A. L. Andreu J. Arenas 《Annals of human genetics》2004,68(1):17-22
We report on 8 Dutch patients with McArdle's disease from 6 unrelated families. Molecular analysis revealed the presence of four previously described mutations: the common R49X mutation, the IVS14+1G>A mutation and the recently reported R269X and Y84X nonsense mutations; and two new molecular defects: a missense mutation R138W in the homozygous state in two siblings, and a frameshift mutation c.1797delT. This first genetic study of patients from The Netherlands with McArdle's disease confirms that the R49X mutation is also the most common in Dutch patients, and that there is genetic heterogeneity within this population. Moreover, our data support the hypothesis that the Y84X mutation is a relatively frequent mutation in McArdle's patients with a Central European background, and expand the already crowded map of mutations within the PYGM gene responsible for McArdle's disease. 相似文献
212.
213.
Antioxidant defence during cardiopulmonary bypass surgery. 总被引:1,自引:0,他引:1
Chris R Luyten Frans J van Overveld Lieve A De Backer Anna M Sadowska Inez E Rodrigus Stefan G De Hert Wilfried A De Backer 《European journal of cardio-thoracic surgery》2005,27(4):611-616
OBJECTIVE: Cardiac surgery may lead to severe oxidative stress due to formation of oxidation products generated during ischemia and reperfusion. We investigated to which extent oxidative stress influences a number of endogenous antioxidants and markers of cellular activation. METHODS: At six time points blood was withdrawn from patients undergoing coronary artery bypass grafting, using the on-pump procedure. RESULTS: Both glutathione peroxidase and superoxide dismutase show a gradual and strong increase in activity during surgery (40 and 30%, respectively), returning to baseline values 24 h after surgery. The total antioxidant capacity has a maximum increase of 60%. Markers of cellular activation, such as eosinophil cationic protein and tryptase also increase during the procedure. CONCLUSION: Cardiac surgery results in systemic inflammation accompanied or caused by severe oxidative stress. The human body has a strong innate oxidative defence screen, which is probably not sufficient to fully compensate for the total amount of oxidative damage. 相似文献
214.
Gerald Buckberg Lorenzo Menicanti Sergio De Oliveira Constantine Athanasuleas 《European journal of cardio-thoracic surgery》2005,28(5):772-774
Left ventricular geometry is distorted after anterior infarction caused by occlusion of a wrap around left anterior descending artery. Loss of the apex creates a spherical left ventricular (LV) chamber, whose rebuilding requires reconstruction techniques that exclude the non-functional inferior wall. The described technique of tailoring the apex defines a way to create an oblique elliptical rim for subsequent patch placement to complete the restoration procedure. This method of ventricular rebuilding differs from methods that follow the inferior wall scar, which result in a restoration procedure that leaves a spherical or box-like apical region. 相似文献
215.
D De AJ Kanwar S Handa 《Journal of the European Academy of Dermatology and Venereology》2006,20(7):853-859
BACKGROUND: Diagnosis of atopic dermatitis (AD) depends on clinical features because no definitive diagnostic test exists. Criteria proposed by Hanifin and Rajka (Acta Derm Venereol (Stockh) 1980; Suppl 92: 44-47) were acceptable for hospital-based studies but were found not to be suitable for field studies. A UK working party formulated clinical diagnostic criteria that could be used in both hospital and epidemiological settings. Validation studies of the criteria showed widely variable results, probably due to different clinical settings and ethnicity. AIM AND OBJECTIVE: This study was undertaken to validate Hanifin and Rajka's criteria and to assess the comparative efficacy of their criteria and the UK working party's diagnostic criteria in the diagnosis of AD in a hospital setting in North India. SUBJECTS AND METHODS: This study serially included 101 patients with AD and 48 controls of paediatric age group. The study period was from July 2003 to December 2004. RESULTS: Hanifin and Rajka's criteria (sensitivity 96%, specificity 93.75%, positive predictive value 97% (PPV) and negative predictive value (NPV) 91.84%) had a statistical advantage over the UK working party's diagnostic criteria (sensitivity 86%, specificity 95.83%, PPV 97.75% and NPV 76.67%), with a P-value < 0.005. 相似文献
216.
L A D'Albuquerque J Gama-Rodrigues M F De Miranda T Genzini P Sakai A A Laudanna H W Pinotti 《International surgery》1991,76(3):137-141
Forty-six patients in the postoperative period of proximal gastric vagotomy (PGV) for duodenal ulcer (DU) were studied comparatively to verify whether the dividing of the gastroepiploic nerves (Rosati's maneuver) can reduce or not the occurrence of recurrent ulcer as it was proposed. Twenty-one patients who underwent PGV associated with Rosati's maneuver (PGV-R) were compared to 25 after standard PGV (PGV-S), according to several criteria: (1) clinical evaluation; (2) pre and postoperative basal and pentagastrin-stimulated gastric acidity; (3) postoperative basal and pentagastrin-stimulated serum pepsinogen; (4) postoperative basal and sham feeding-stimulated serum gastrin; (5) postoperative endoscopy; (6) endoscopic Congo red test. Both groups were similar (P greater than 0.05) as to age, sex, levels of preoperative gastric acidity and had a 24.4 month average follow-up (12 to 58 months). There has been no significant difference between the techniques studied as to clinical, secretory, morphological or hormonal gastric tests, although PGV-R proved more effective in reducing basal gastric acidity than PGV-S (P less than 0.05). We concluded that Rosati's maneuver does not improve the results obtained with PGV, although it provided greater reduction of basal gastric acidity than PGV-S. 相似文献
217.
218.
219.
Torsades de pointes after intracoronary papaverine 总被引:2,自引:0,他引:2
Coronary blood flow velocity and coronary flow reserve can be assessed in humans using a coronary Doppler catheter and the vasodilator papaverine. Although it is a safe, elegant and reproducible technique, serious complications can occur. Coronary flow reserve assessment in a 49-year-old man with a critical stenosis in the proximal part of the circumflex artery was complicated by a papaverine-induced ventricular arrhythmia. Several features of the present case report support papaverine-induced disturbances of the repolarization phase as the pathophysiological mechanism: a 'torsade de pointes' pattern of the tachycardia, the lengthening of the QT-interval, the appearance of a new U-wave and the presence of additional risk factors (hypokalaemia and alcalosis). Patients presenting additional risk factors for this complication should be excluded from coronary flow reserve assessment. 相似文献
220.
Paolo Martinelli Giovanni Rizzo David Manners Caterina Tonon Fabio Pizza Claudia Testa Cesa Scaglione Bruno Barbiroli Raffaele Lodi 《Movement disorders》2007,22(8):1182-1185
The pathophysiology of essential tremor (ET) is unknown. PET and fMRI studies have revealed bilateral activation and (1)H-MRS studies metabolic abnormalities in the cerebellum and other functionally related brain structures in ET. Diffusion-weighted imaging (DWI) was used to search for evidence of tissue integrity abnormalities in these areas in ET patients and 10 matched controls by calculating water apparent diffusion coefficients (ADCs). Regions of interest included the left and right cerebellum, red nucleus, thalamus, caudate, putamen, pallidum, and frontal white matter. Histograms of ADCs were generated for all pixels in the infratentorial compartment and manually segmented areas corresponding to brainstem, vermis, and cerebellar hemispheres. ADC values were similar in all brain areas in patients and controls. Our study did not detect changes affecting the investigated brain regions in ET patients. These findings argue against major structural damage in the ET brain, although more subtle neurodegenerative changes cannot be ruled out. 相似文献