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991.
Prenatal diagnosis of a congenital coronary artery fistula between the left coronary artery and the right ventricle was established at 28 weeks of gestation. Hydrops fetalis developed during follow‐up and the baby died on the first day after delivery. It is rare for coronary artery fistulas to become symptomatic during fetal life. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound, 43 :129–131, 2015  相似文献   
992.
Purpose Our aim was to explore whether vitamin A has protective effect on high-dose-methotrexate (HDMTX)-induced intestinal D-xylose malabsorption in children with leukemia and lymphoma.Patients and methods We performed a prospective randomized unblinded study of vitamin A in 35 children with leukemia and lymphoma who were planned to receive HDMTX 3 g/m2 and 5 g/m2, respectively. Twenty-two patients (group 1) received a single dose of 180,000 IU a day before HDMTX was given, and 13 (group 2) received only HDMTX. The vitamin A group received the vitamin only once. Oral D-xylose absorption tests before and 7 days after HDMTX were carried out to evaluate intestinal absorption. Retinol-binding protein (RBP) levels prior to therapy were also measured for vitamin A status.Results Although we observed no difference of HDMTX-induced toxicity, including hematological, dermatological, systemic, and other toxicities, between groups, the D-xylose absorption test was significantly better in-group 1 (p=0.030). Absorption was decreased in five of 22 patients (23%) who received vitamin A comparing to eight of 13 (62%) who received only HDMTX (p=0.033). RBP levels were lower than normal in 13 of 22 patients in-group 1 and nine of 13 in group 2. In patients whose RBP levels were lower than normal, HDMTX-induced toxicity was lower in the group 1 than group 2 but not statistically significant. No sign of vitamin A toxicity was observed throughout the study.Conclusion The administration of vitamin A before HDMTX may protect against drug-induced D-xylose malabsorption in children with cancer. Further studies are apparently needed to clarify the full benefits of vitamin A in preventing HDMTX-induced mucosal damage.  相似文献   
993.
In between the dates of February 2008–March 2009, by applying to Istanbul University CTF Microbiology and Clinical Microbiology Basic Sciences Branch and Duzen laboratories, 123 cases, where HCV RNA and anti-HCV positivity are identified with molecular (real-time PCR) and serologic (ELISA) methods as a positive control group, and 48 cases where HCV RNA and anti-HCV negativity are identified as a negative control group are established. The values of sensitivity, specificity, positive and negative approximation of recently developed HCV Core Ag (Abbott Diagnostics, Germany) kit are determined successively as 94.3%, 97.9%, 99.1%, 87%, 95.3% and 88%. Although the new HCV Ag assay is clearly not sensitive enough to replace HCV NAT it may serve as a valuable tool in the HCV diagnostic algorithm as it is able to pick up a great majority of anti-HCV and HCV RNA positive samples, thus allowing a timely and less expensive serological diagnosis of an active HCV infection. This may be an advantage for labs that do not have access to PCR easily.  相似文献   
994.
The myocardial performance index (MPI) reflects both the systolic and diastolic function of the heart, and is easily applied in practice. In this study, we aimed to determine the relationship between MPI and invasive haemodynamic parameters in heart failure patients. A total of 126 patients with heart failure were selected, all of whom were referred for diagnostic cardiac catheterisation, and were divided into two groups. Group I consisted of 59 patients (32 men and 27 women, mean age 61 ± 10; functional capacity New York Heart Association (NYHA) Class I; and left ventricular end-diastolic pressure (LVEDP) <16 mmHg). Group II included 67 patients (34 men and 33 women, mean age 60 ± 9; NYHA Class ≥ II; LVEDP ≥ 16 mmHg). The following parameters were measured in all patients: ejection fraction with Simpson method, the peak mitral early (E) and late (A) diastolic velocities, E/A ratio, deceleration time (DT) and tissue Doppler from four different areas of the mitral annulus (septum, lateral, inferior and anterior). In order to measure MPI with two methods (standard Doppler and tissue Doppler), isovolumetric contraction time (IVCT), isovolumetric relaxation time (IVRT) and ejection time (ET) were measured from four areas and mean values of MPI were calculated. There was no difference between the two groups in E/A ratios, DT and IVRT (p > 0.05). Group II patients had longer IVCT and ET, when compared with group I patients (p < 0.05). MPI, measured by both standard pulsed wave Doppler and tissue Doppler methods, was significantly higher in group II patients, when compared with the values obtained from group I patients (Group I: 0.50 ± 0.2 and 0.50 ± 0.14; group II: 0.98 ± 0.3 and 1.2 ± 0.32; p < 0.001). According to receiver operating characteristics curve analysis, the cut-off value for MPI measured by tissue Doppler was 0.74. The sensitivity and specificity of this value were measured as 92.5 and 91.5 %, respectively. MPI measured by standard Doppler method was 0.67, and its sensitivity and specificity were 85.1 and 83.1 %, respectively. We found a strong relationship between MPI and LVEDP (r = 0.83, p < 0.001; r = 0.96, p < 0.001), especially when measured by tissue Doppler. In addition, we observed a significant relationship between the MPI values measured by tissue Doppler and those measured by standard traditional methods (r = 0.85, p < 0.001). We showed that MPI was reliable for the evaluation of global cardiac functions in patients with heart failure, as measured with both pulsed-wave Doppler and tissue Doppler. We assert that, in order to differentiate between those patients with symptomatic heart failure from the asymptomatic cases, MPI as measured with the tissue Doppler method is an improvement on MPI as measured using traditional methods.  相似文献   
995.
Tethered spinal cord is mostly caused by myelomeningocele and lipomyelomeningocele, while dermal sinus tract, diastematomyelia, lipoma, tumor, thickened/tight filum terminale, spinal trauma, and spinal surgery are among the other causes. Prenatal diagnosis of tethered cord has been reported, and it is usually associated with neural tube defects. We present an atypical presentation of a tethered spinal cord, which was associated with a sacrococcygeal teratoma and was diagnosed in the 23rd week of pregnancy by ultrasonography. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 44 :506–509, 2016  相似文献   
996.
PURPOSE: To assess via Doppler sonography the hemodynamic changes in the cephalic vein after creation of an arteriovenous fistula, and to compare radiocephalic and brachiocephalic fistulas. METHODS: Thirty-three hemodialysis patients and 54 controls were enrolled in the study. The cephalic vein was examined with a 7.5-MHz linear-array transducer. Doppler waveform parameters (resistance index, pulsatility index), time-averaged maximum flow velocity (TAV), peak systolic velocity (PSV), end-diastolic velocity (EDV), and the cross-sectional area of the vessel (A) were measured. Cephalic vein flow volume (CVFV) was calculated as TAV x A. RESULTS: CVFV, PSV, EDV, A, RI, and PI were 45.5, 7.2, 6.7, 7.7, 1.2, and 1.32 times higher, respectively, in the cephalic vein of hemodialysis patients compared with controls. Both CVFV and A were higher in brachiocephalic patients compared with radiocephalic patients (1,983 +/- 1,199 versus 870 +/- 322 ml/min [p < 0.05] and 50.3 +/- 38.9 versus 21.0 +/- 7.8 mm(2) [p < 0.05], respectively). CONCLUSION: The increase in cross-sectional area and flow volume of the cephalic vein is larger in patients with brachiocephalic fistulas than in those with radiocephalic fistulas; however, flow velocities and waveform parameters are not different.  相似文献   
997.
998.

Objective

To study subsequent pregnancy outcome in women with severe, very early onset preeclampsia (onset before 24 weeks’ gestation) and to analyze cardiovascular risk profiles of these women and their partners.

Study design

Twenty women with preeclampsia with an onset before 24 weeks’ gestation, admitted between 1 January 1993 and 31 December 2002 at a tertiary university referral center, were enrolled in the study. Data on subsequent pregnancies were obtained from medical records. Their cardiovascular risk profiles and those of their partners (n = 15) were compared with those of 20 control women after uncomplicated pregnancies only, matched for age and parity, and those of their partners (n = 13). Body weight, height, waist and hip circumference, blood pressure and intima media thickness (IMT) of the common carotid artery were measured. Fasted blood samples were drawn for detection of metabolic cardiovascular risk factors.

Results

Of the 20 case women 17 women had 24 subsequent pregnancies, of which 12 (50%) were complicated by preeclampsia. Severe preeclampsia developed in five (21%) pregnancies. No perinatal deaths occurred. Case women had significantly more often chronic hypertension as compared to controls (55% vs. 10%, P = 0.002). IMT of the common carotid artery was increased in a subset of case women using antihypertensive medication (P = 0.03). Case women showed increased microalbuminuria (P < 0.05). No differences were found in cardiovascular risk profiles between partners of cases and controls.

Conclusions

Women with severe, very early onset preeclampsia have an increased risk of preeclampsia in future pregnancies, yet neonatal outcome is, in general, favourable. Regarding cardiovascular health, women after severe, very early onset preeclampsia exhibit more risk factors compared to controls whereas men who fathered these pregnancies do not.  相似文献   
999.
Endothelin levels in Henoch-Schonlein purpura   总被引:5,自引:0,他引:5  
Henoch-Schonlein purpura (HSP) is one of the most common types of vasculitis disorders seen in childhood and is characterized by a rash, arthritis, abdominal pain, and renal involvement. Although HSP is an immunoglobulin A (IgA) related immune complex disease, the pathogenesis has not been fully elucidated. Cytokines have been implicated in the pathogenesis, but endothelins (ET) - vasoconstrictor hormones produced by endothelial cells - have not been studied in patients with HSP. In a controlled study, we measured ET-1 levels in children with HSP during the acute and remission phases. ET-1 levels were significantly higher in the HSP patients during the acute phase compared with the control group and the HSP patients in the remission phase. There was no correlation between ET-1 levels and disease severity, acute phase reactant response, or morbidity. The role of endothelins and other cytokines in the pathogenesis of HSP needs to be further explored.  相似文献   
1000.
Background: Effective treatment and prevention of hyperthermia and shivering-like tremor during labor is hindered by a poor understanding of their causes. The authors sought to identify the incidence of nonthermoregulatory shivering-like tremor and the factors associated with this activity.

Methods: The authors studied women in spontaneous fullterm labor who chose epidural analgesia (n = 21) or opioid sedation (n = 31). Shivering-like tremor and sweating were evaluated by observation. Core temperature was recorded in the external auditory canal using a compensated infrared thermometer. Arteriovenous shunt tone was evaluated with forearm minus fingertip skin temperature gradients; gradients less than 0 were considered evidence of vasodilation. Tremor was considered nonthermoregulatory when core temperature exceeded 37 [degree sign]C and the arms were vasodilated. Pain was evaluated using a visual analog scale.

Results: Shivering-like tremor was observed in 18% of 290, 30-min data-acquisition epoch before delivery. The patients were both normothermic and vasodilated during 15% of these epochs. Shivering was observed in 16% of 116 postdelivery epochs and was nonthermoregulatory in 28%. Sweating was observed in 30% of predelivery epochs, and the patients were both hypothermic and vasoconstricted during 12%. The mean core temperature in patients given epidural analgesia was approximately 0.2 [degree sign]C greater than in those given sedation. Hyperthermia was observed during 10 epochs (38.4 +/- 0.3 [degree sign]C) during epidural analgesia and during 10 epochs (38.4 +/- 0.3 [degree sign]C) with sedation. The patients were vasoconstricted in more than 50% of these epochs in each group. Multivariate mixed-effects modeling identified high pain scores and vasoconstriction as significant predictors of shivering. There were no predictors for shivering epochs in patients who were simultaneously normothermic and vasodilated. Significant predictors of sweating were time before delivery, high pain scores, hypothermia with vasoconstriction, high thermal comfort, and low mean skin temperature. There were no predictors for sweating epochs in patients who were simultaneously hypothermic and vasoconstricted.  相似文献   

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