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991.
Two principal types of osteopetrosis have been distinguished. One is the dominantly inherited, relatively benign condition which is often detected radiologically in asymptomatic adults. A second type is the recessive, lethal, malignant form. Autosomal dominant osteopetrosis (ADO) has two distinct radiological subtypes known as types I and II. We report here a 23-year-old patient with ADO type II. Radiographic investigations of a skeletal survey showed generalised osteosclerosis with thickened cortex. Magnetic resonance imaging (MRI) scan disclosed osteosclerosis in superior and inferior portions of the vertebral bodies which produced a 'sandwich' appearance. The 'bone-within-bone' appearance was seen in the ileum of the patient. The vertebral bone density was found markedly elevated. The carbonic anhydrase II level was found to be normal. We discuss here the genetic etiology of this disorder. 相似文献
992.
High-molecular-weight kininogen is exclusively membrane bound on endothelial cells to influence activation of vascular endothelium 总被引:3,自引:1,他引:3
An important biologic function of high-molecular-weight kininogen (HK) is to deliver bradykinin (BK) to its cellular receptors. Internalization and degradation of HK may provide a mechanism by which endothelial cells modulate the production of BK and control its activities. Therefore, we investigated the binding and subsequent distribution of biotinylated-HK (biotin-HK) associated with human umbilical vein endothelial cells (HUVEC). HUVEC bound 3 to 4 times more HK and with greater avidity at 1 to 3 hours at 37 degrees C than at 4 degrees C (Bmax = 1.0 +/- 0.02 x 10(7) molecules/cell, kd = 7 +/- 3 nmol/L v Bmax = 2.6 +/- 0.2 x 10(6) molecules/cell, kd = 46 +/- 8 nmol/L). However, there was no evidence that the difference was caused by internalization of HK at the higher temperature. First, the same amount of biotin-HK was associated with nonpermeabilized and permeabilized HUVEC using buffers containing 20 to 50 mumol/L zinc ion in the absence or presence of 2 mmol/L calcium ion. Second, binding of biotin-HK to HUVEC was approximately 92% reversible at 1 hour when the cells were maintained at both 37 degrees C and 4 degrees C. Third, neither chloroquine nor primaquine altered the amount of biotin-HK bound to HUVEC. Fourth, biotin-HK bound to HUVEC was almost completely removed by pronase. Fifth, the nonpermeable dye, crystal violet, almost completely quenched the fluorescence signal emitted by HUVEC-associated fluorescein isothiocyanate (FITC) HK. Finally, the localization of HUVEC-bound FITC-HK was restricted to the membrane as shown by laser scanning confocal microscopy. The expression of HK binding sites had an absolute requirement for metabolic energy, but was not dependent on new protein synthesis. Membrane-bound HK contributed to the anticoagulant nature of endothelial cells by blocking human alpha-thrombin binding and its resultant induction of prostacyclin formation. These studies indicate that HK is not internalized by HUVEC, but remains primarily on cell surfaces to be accessible for BK liberation and to modulate the binding and actions of alpha-thrombin. 相似文献
993.
Atak R Ileri M Yetkin O Yetkin E Turhan H Senen K Sahin O Ozbakir C Demikan D 《Angiology》2004,55(6):661-667
Determination of underlying etiology in patients with dilated and globally hypokinetic left ventricles may sometimes be difficult even after detailed history and complete clinical evaluation. Cardiac valvular and thoracic aortic calcifications have previously been reported to be used as a window to diffuse atherosclerosis of the vascular system. The authors prospectively examined the predictive value of mitral annular calcification (MAC), aortic valve calcification (AVC), and thoracic aortic calcification (TAC) in diagnosis of coronary artery disease as the underlying cause of diffuse left ventricular dilatation and systolic dysfunction. The study included 98 consecutive patients (male/female = 76/22, mean age = 58.9 +/- 10.7 years, range: 33 to 75 years) over the age of 30 years admitted to their clinics between October 1999 and December 2001 with signs and symptoms of congestive heart failure associated with documented cardiomegaly. Transthoracic echocardiography and coronary angiography were performed in all patients for the evaluation of valvular calcifications and coronary status. Although there was no significant difference between the groups with and without coronary artery stenosis (CAS), with regard to presence of MAC, patients with CAS tended to have MAC more frequently (12/61, 20% vs 4/37, 11%, p > 0.05). AVC and TAC were found to be significantly more frequent in patients with CAS compared to those without CAS (AVC, 35/61, 57% vs 4/37, 11%, p < 0.001 and TAC, 28/61, 46% vs 2/37, 5%, p < 0.001). While all 3 calcifications had sensitivity under 60%, and specificity and positive predictive value over 75% individually, the presence of any of them had a sensitivity of 80%, specificity of 86%, positive predictive value of 91%, and negative predictive value of 73%. Thus the presence of any of these calcifications distinguished patients with coronary artery disease with a sensitivity of 80% and specificity of 86%. The presence of aortic valvular valve and thoracic aortic calcifications seems to be associated with significant coronary arterial stenosis; however, with relatively low negative predictive values these cannot be used in clinical practice for diagnosis of underlying coronary artery disease in patients with dilated left ventricles and impaired systolic functions. 相似文献
994.
995.
Kadir Bahar Selim Karayal?in Muhsin Kaya Hülya Cetinkaya Hakan Bozkaya Cihan Yurdaydin 《The Turkish journal of gastroenterology》2002,13(2):83-88
BACKGROUND/AIMS: In patients with Budd-Chiari syndrome due to short segment hepatic vein stenosis where percutaenous transluminal venoplasty is not successful, percutaneous transhepatic balloon venoplasty may be a valid treatment option. The aim of this prospective study was to evaluate the effects of this procedure for the treatment of patients with Budd-Chiari syndrome, in whom transluminal cannulation was unsuccessful. METHODS: Ten patients with short segment occlusion of the hepatic veins were treated by percutaneous transhepatic balloon venoplasty between January 1997 and January 2000. The median follow-up period of these patients was 20 months (2-33 months). RESULTS: The procedure was unsuccessful in two patients. Eight patients (five men, three women) with a median age of 28 (range, 15-61) years were treated by percutaneous transhepatic balloon venoplasty and in seven of them, clinical symptoms including abdominal distension and ascites, resolved completely. Long term anticoagulation therapy was not given to the patients. One patient with advanced stage liver disease died of variceal bleeding two months after the procedure. During follow-up, symptomatic reocclusion requiring dilatation occurred in three patients. CONCLUSIONS: Percutaneous transhepatic balloon venoplasty is an alternative treatment option for selected patients with Budd-Chiari syndrome when transluminal cannulation of the hepatic veins is not possible. Long term anticoagulation therapy seems to be necessary in these patients. 相似文献
996.
Okan T Sari I Akar S Cece H Goldeli O Guneri S Akkoc N 《Echocardiography (Mount Kisco, N.Y.)》2008,25(1):47-56
OBJECTIVE: The aim of this study was to evaluate ventricular functions by using standard Doppler echocardiography (SDE), myocardial performance index (MPI), and pulsed wave tissue Doppler imaging (PW-TDI) in patients with ankylosing spondylitis (AS) and healthy controls. METHODS: Forty-nine AS patients (38 +/- 11 years, 25 M/24 F) and 33 controls (36 +/- 9 years, 17 M/16 F) were studied. Two-dimensional, M-Mode, SDE, PW-TDI echocardiography examinations were performed. Spinal mobility was assessed by the Bath ankylosing spondylitis metrology index (BASMI) measurement. Patients were also evaluated using the Bath ankylosing spondylitis functional index (BASFI) and the Bath ankylosing spondylitis disease activity index (BASDAI). RESULTS: Four control subjects and six AS patients met the left ventricular (LV) diastolic dysfunction (DD) criteria by using conventional Doppler echocardiography (p > 0.05). However, using PW-TDI method 22 patients in the AS group and six subjects in the control group were diagnosed to have LV DD (Em/Am < 1). Pseudonormalized pattern was present in 16 AS patients and two control subjects. Correlation analysis revealed significant moderate negative correlations between Em/Am and BASMI, age and body mass index (p < 0.05; r =-0.3, -0.6, and -0.4, respectively). No correlation was observed between Em/Am and disease duration, BASFI, BASDAI, CRP, and ESR. We could not detect any right ventricular function involvement either by conventional or by recently introduced echocardiography methods. The risk of developing LV DD was found to be 3.7 times higher in AS patients. CONCLUSION: When sensitive echocardiographic Doppler techniques such as MPI, TDI-derived MPI, and PW-TDI are utilized, DD can be detected in a significant proportion of patients with AS without cardiovascular (CV) disease which may contribute CV mortality in these patients. 相似文献
997.
Thirty nine patients undergoing surgery for chronic pancreatitis were investigated for evidence of hepatobiliary disease. In addition to pre-operative assessment by liver function tests, ultrasound, ERCP (in 33) and percutaneous transhepatic cholangiography (in five), all had peroperative liver biopsy. Common bile duct stenosis was diagnosed in 16 (62%) of the 26 patients with successful cholangiography. Features of extrahepatic biliary obstruction were found on biopsy in 11 patients, three of whom showed features of secondary sclerosing cholangitis. No patients had secondary biliary cirrhosis. Three had parenchymal liver disease (cirrhosis, resolving hepatitis and alcoholic hepatitis respectively) and two others had features suggestive of previous alcohol-induced injury. Five (83%) of the patients with clinical jaundice had biopsy features of extrahepatic biliary obstruction, as did eight (67%) with alkaline phosphatase above twice normal and seven (44%) with radiological common bile duct stenosis. Neither alkaline phosphatase rise, nor common bile duct stenosis alone or in combination, were a reliable indication of the need for biliary enteric bypass surgery. Pre-operative liver biopsy may be a valuable adjunct in the assessment of such patients. 相似文献
998.
999.
Döven O Pekdemir H Camsari A Cicek D Katircibaşi MT Atalay A Akkus MN Cin VG 《Heart and vessels》2004,19(5):230-236
The optimal treatment for in-stent restenosis (ISR) is a subject of controversy. Recently, FX minirail balloon angioplasty (BA) has emerged as a management tool for ISR. We assessed the hypothesis that the FX minirail BA has advantages over conventional percutaneous transluminal balloon angioplasty (PTCA) in the treatment of ISR. FX minirail BA or PTCA were applied to 116 patients with ISR (145 lesions) at our institution. Using a computer algorithm, an attempt was made to match each lesion in the FX minirail BA group with a corresponding lesion in the PTCA group. The lesion pairs should match with respect to the patients age and sex, type of target vessel and stent, reference vessel diameter, and baseline minimal lumen diameter (MLD). Following the matching process, 46 ISR lesion pairs were identified. Baseline patient characteristics were similar among the groups (P = not significant). There was no difference in the in-hospital major adverse cardiac events (MACE) between the groups, whereas MACE at follow-up were significantly lower in the FX minirail BA group than in the PTCA group (19.6% vs 41.3%, P < 0.05). The recurrent ISR rate was significantly lower in the FX minirail BA group than in the PTCA group (19.6% vs 39.1%, P < 0.05). Also, a diffuse pattern of recurrence was more common in lesions treated with PTCA, whereas the focal pattern of recurrence was more common in the FX minirail BA group (22.2% vs 50%, P < 0.05). The MLD at follow-up, the acute gain, and net gain were significantly higher in the group of lesions treated with the FX minirail BA than in the PTCA group. In addition, a significantly higher late loss and loss index at follow-up were observed in the PTCA group compared in the FX minirail BA group. The FX minirail BA has advantages over PTCA in the treatment of patients with ISR, with better immediate and follow-up angiographic outcomes, and a better clinical outcome on follow-up. 相似文献
1000.
José Dizon Evelyn Horn John Neglia Norma Medina Hasan Garan 《Journal of interventional cardiac electrophysiology》2004,10(1):47-50
Cardiac resynchronization therapy has been proven to improve symptoms and indices of left ventricular function in patients with heart failure and intraventricular conduction delays. We present a case of a patient with New York Association Class III heart failure and left bundle branch block, who received a biventricular pacemaker in order to achieve cardiac resynchronization. Her symptoms improved markedly, as did left ventricular ejection fraction and dimensions. In addition, her intrinsic QRS duration normalized. This may represent a salutory effect of biventricular pacing on electrical remodeling. 相似文献