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Dr. U. Yilmaz 《Der Radiologe》2012,52(12):1095-1100
Intracranial arterial stenoses clinically present as acute, fluctuating or recurrent neurological deficits which are caused by hemodynamically impaired perfusion of the corresponding area of the brain. The type and the extent of the deficit, however, are not only determined by the location of the stenosis but also depend on the individual anatomical conditions of the patient, such as the degree of collateralization and variants of the circle of Willis. 相似文献
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Yelda Tayyareci M.D. Selen Yurdakul M.D. Gulsah Tayyareci M.D. Yilmaz Nisanci F.E.S.C. Berrin Umman M.D. Zehra Buğra M.D. 《Echocardiography (Mount Kisco, N.Y.)》2010,27(10):1211-1218
Aim: In diabetes mellitus (DM) patients, left ventricular dysfunction is widely evaluated and established by conventional diagnostic methods, whereas right ventricular (RV) function is not as sufficiently evaluated. The aim of this study is to assess the preclinical effects of DM on RV function by using novel Tissue Doppler Imaging (TDI)‐derived indices. Methods: The study included 96 patients with type II DM [60 with DM only and 36 patients with coexisting DM and hypertension (DMHT)] and 40 healthy controls. Conventional parameters and TDI‐derived systolic velocities of tricuspid annulus [isovolumic myocardial acceleration (IVA), peak myocardial velocity during isovolumic contraction (IVV), peak systolic velocity during ejection period (Sa), RV Tei index] were measured. Results: TDI‐derived RV IVA was significantly lower in both DM and DMHT patients compared to controls indicating subclinical impairment in RV systolic function in the study patients (P = 0,0001). However RV IVA was similar in DM and DMHT subgroup supporting RV systolic impairment in DM was independent from HT. In correlation analysis, RV IVA was significantly correlated with the existence of diabetic nephropathy (r =?0,38; P = 0,003), retinopathy (r =?0,35; P = 0,006), insulin resistance (r =?0,52; P = 0,0001). Conclusions: Diabetes is associated with subclinical RV systolic dysfunction, regardless of coexisting hypertension. Tissue Doppler‐derived IVA; is a novel, non‐invasive parameter which may be used in early detection of RV systolic dysfunction in patients with DM. (Echocardiography 2010;27:1211‐1218) 相似文献
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Kuehne T Yilmaz S Steendijk P Moore P Groenink M Saaed M Weber O Higgins CB Ewert P Fleck E Nagel E Schulze-Neick I Lange P 《Circulation》2004,110(14):2010-2016
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Wenjie Wang Brendan Murphy Serdar Yilmaz Marcello Tonelli Jennifer MacRae Braden J. Manns 《Clinical journal of the American Society of Nephrology》2008,3(1):78-84
Background and objectives: Concern about primary fistula failure may contribute to the underuse of arteriovenous fistula. The objective of this study was to investigate the baseline clinical parameters associated with primary fistula success.Design, setting, participants, & measurements: Consecutive incident patients who commenced dialysis during a 28-mo period in a regional renal program were studied. Data on patient-related variables and on surgical approach (e.g., whether the surgeons routinely assess vessel size during the operation) were collected. Primary fistula success was defined as an arteriovenous fistula that was able to afford successful dialysis for 3 h with blood pump speed of ≥300 ml/min for three consecutive sessions.Results: A total of 205 (69%) patients had an AVF attempted as their first vascular access. The overall primary success rate was 64% and was similar for radiocephalic and brachiocephalic fistula. Logistic regression was done separately for patients with the two types of fistula because of the presence of statistical interaction. For radiocephalic fistula, male gender was the only parameter associated with primary fistula success (odds ratio 3.57; P = 0.01). The presence of comorbidity was not significantly associated with primary fistula failure.Conclusions: Despite significant patient comorbidity, there was a high primary fistula success rate among this incident hemodialysis cohort. Given that vessel size may be the ultimate determinant of fistula success, if surgeons assess vessel size perioperatively, then the presence of significant comorbidity might not preclude arteriovenous fistula from being attempted as the initial access.Given the well-documented advantages of arteriovenous fistula (AVF) over arteriovenous graft and central venous catheter (CVC), the current Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines suggest that AVF should be attempted as the initial vascular access in at least 50% of incident patients and that at least 40% of prevalent hemodialysis (HD) patients should undergo dialysis with an AVF (1–5). Despite these recommendations, it is clear that AVF are underused in many centers in North America, especially when compared with European centers (6,7). Recent data suggest that only 32% of prevalent US HD patients undergo dialysis with an AVF (8). In Canada, AVF are used by 53% of prevalent and only 26% of incident HD patients (7).One of the fears that may reduce the use of AVF is the high primary fistula failure rate (i.e., failure of AVF to mature) (9). Identifying risk factors that contribute to primary fistula failure may help clinicians and patients make an informed decision as to for whom to attempt an AVF. Only a few studies have prospectively examined the risk factors associated with primary fistula failure, which has been reported in 20 to 50% of patients (9–12).Most studies that have evaluated factors that are associated with primary fistula failure have typically used a retrospective design. For instance, Miller et al. (10) reported higher primary fistula failure rate in older and female patients with diabetes, although small numbers and a highly selected patient population limit the generalizability of these results. Feldman et al. (13) published data from a larger cohort (348 patients), reporting a primary success rate of 54%. Preexisting cerebrovascular disease, older age, and commencement of dialysis before access creation were noted to be associated with higher primary fistula failure in their study. Ravani et al. (11) noted that cardiovascular disease and late referral to nephrologists were associated with lower primary AVF success in patients from northern Italy.More recently, Lok et al. (14) studied a cohort of 422 HD patients who were undergoing their first AVF placement to identify preoperative clinical characteristics that are predictive of fistula failure to mature and to use this information to develop a prediction rule to estimate the risk for fistula failure to mature. This prediction rule was validated in an external data set from five North American centers. Age, peripheral vascular disease, coronary artery disease, and white race all were associated with fistula failure to mature in their study; however, in this and the previously mentioned studies, it is not clear whether there was any consistent surgical assessment performed perioperatively to guide fistula placement; as such, the results may not be applicable to programs that use pre- or intraoperative surgical assessment to guide fistula placement.Given these uncertainties, we sought to determine the association of various baseline clinical parameters with primary fistula success in a cohort that consisted of all incident dialysis patients between July 1, 1999, and November 1, 2001, in Calgary, Alberta, Canada, the majority of whom had an indirect assessment of vessel diameter intraoperatively to guide the location of fistula placement. 相似文献
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FOX K.; POOL J.; VOS $$$; LUBSEN J.; ON BEHALF OF THE ROCKET-STUDY GROUP 《European heart journal》1991,12(8):1283-1287
This study was designed to examine the effects of nisoldipine(relative to placebo), a new dihydropyridine calcium entry blockingagent, in the treatment of silent ischaemia in conventionaldoses. A total of 409 patients with proven coronary artery diseasewere screened and of this 64 had at least six episodes or atotal duration of 30 mm of ST segment depression (1 mm lastingat least 1 min) over 48 h. Fifty-two patients ultimately completeda randomized double-blind cross-over study comparing nisoldipine5 mg twice a day, nisoldipine 10 mg daily and placebo. There was a reduction in the ST segment integral and numberof episodes of ST segment depression when compared to placeboon treatment with nisoldipine 5 mg twice a day and nisoldipine10 mg daily. However, the confidence limits were wide and crossedthe no-treatment effect line. In addition, the nisoldipine dosesneither affected the circadian distribution of ischaemic episodesnor caused an alteration of the workload achieved either atpeak exercise or at 1 mm ST segment depression measured 24 hafter nidoldipine 10 mg or 12 h after nisoldipine 5 mg. We conclude that frequent silent ischaemia in patients withproven coronary artery disease is relatively uncommon, it accountsfor approximately 16% of patients with positive exercise. Inthese patients nisoldipine, given as 5mg twice a day and 10mg daily, showed no significant therapeutic effects, eitheron the frequency or severity of silent ischaemia. New formulationsof slow release nisoldipine are consequently being developedso that a fuller 24 h therapeutic profile may be obtained. 相似文献
59.
BADANO L.; BERTOLI D.; ASTENGO D.; CARRATINO L.; DEGAETANO G.; PASSERONE G. C.; CAMERIERI A.; GRAMENZI S.; MAGAJA O.; FAZZINI L.; PAPAGNA D.; BIANCHI F.; BARBERIS L.; LUCATTI A.; ON BEHALF OF THE VALVE PROSTHESES LIGURIAN COOPERATIVE DOPPLER STUDY 《European heart journal》1993,14(12):1602-1609
Doppler echocardiographic characteristics of normally functioningAllcarbon prostheses were studied in 149 consecutive patientswith 157 valves in the mitral (n=73) and aortic (n=84) positionswhose function was considered normal by clinical and echocardiographicevaluation. In the mitral position, the mean gradient and theeffective mitral orifice area were not significantly differentin either the 25-mm or the 31-mm size valves (from 5±1to 4±1 mmHg and from 2.2±0.6 to 2.8±0.9cm2, respectively; P=ns for both). Conversely, peak gradientwas significantly and inversely correlated to actual orificearea (r=0.70; P<0.0006), decreasing from 15±3mmHg in the 25-mm size valve to 9±1 mmHg in the 31-mmsize. In the aortic position, the mean gradient was 29±8 mmHgin the 19-mm size valve; it decreased to 8±2 mmHg inthe 29-mm size. Effective prosthetic aortic valve area, calculatedusing the continuity equation, ranged between 0.9±0.1cm2 for the 19-mm size valve to 4.1±0.7 cm2 for the 29-mmsize. By analysis of variance, effective prosthetic aortic valvearea differentiated various valve sizes (F=25.3; P<0.0001)better than peak (F=5.34; P=0.012) or mean (F=4.34; P=0.0052)gradients alone, and it correlated better with actual orificearea (r=0.89, r=0.70 and r=0.65, respectively).This study provides the normal range for Doppler haemodynamiccharacteristics of the various sizes of the Allcarbon valvein the mitral and aortic positions so that prosthetic malfunctioncan be identified. 相似文献
60.
Karti SS Ovali E Ozgur O Yilmaz M Sonmez M Ratip S Ozdemir F 《Hepato-gastroenterology》2003,50(54):1864-1866
BACKGROUND/AIMS: Apoptotic and anti-proliferative effects of heparin on a number of cancers have been described. There have been no studies analyzing the effect of heparin on human hepatoma cells. The aim of this study was to investigate the effect of heparin on human hepatoma cell line, HepG2. METHODOLOGY: HepG2 cell line was cultured with different concentrations of heparin. Colony count, viability assay, percentage of the apoptosis and proliferative index were assessed at the end of the 7th day. Trypan blue was used to assess viability. Apoptosis and proliferative indexes were assessed by flow-cytometry. RESULTS: Hepatoma cells were arrested at the G0/G1 phase with heparin incubation and proliferative indexes decreased significantly in 20, 40 and 80 U/mL of heparin concentrations in comparison with the control (36 +/- 1%, 30 +/- 5% and 29 +/- 8% vs. 44 +/- 1%, p < 0.01). Flow cytometry revealed a statistically significant increase in apoptosis in groups incubated with 40 and 80 U/mL of heparin in comparison with the control (39 +/- 26% and 58 +/- 18% vs. 0.83 +/- 1.3%, p < 0.01). Colony counts per well and viable cells per microL decreased significantly in 80 U/mL of heparin. CONCLUSIONS: Heparin leads to a significant anti-proliferative and an apoptotic effect on human hepatoma cells in vitro. 相似文献