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121.

Background and Aim to Read

We report the results of a bicuspid expanded polytetrafluoroethylene (ePTFE) valved conduit used for right ventricular outflow tract reconstruction (RVOTR).

Methods

Between November 2005 and February 2009, 12 conduits were used for RVOTR. The mean age and weight of patients were 43.5 ± 46.4 months and 13.4 ± 8.6 kg. The main diagnosis was tetralogy of Fallot with pulmonary atresia in eight patients. The most common conduit size was 18 mm. The mean follow‐up was 88.0 ± 35.9 months.

Results

There were no operative and late mortalities. At discharge, the mean peak systolic pressure gradient across the RVOT was 14.1 ± 11.3 mmHg. There was no conduit valve regurgitation in nine patients. At the latest echocardiography (mean follow‐up: 84.3 ± 35.5 months), the mean peak systolic pressure gradient across the RVOT was 59.7 ± 20.2 mmHg, and there was no conduit valve regurgitation in six patients. Freedom from conduit malfunction was 100% and 83.3%, at 1 and 8 years, respectively. Two conduits were explanted due to sternal compression and four from conduit malfunction. Freedom from explantation was 83.3% and 74.2% at 2 and 8 years, respectively.

Conclusions

ePTFE bicuspid valved conduit has good late function in terms of valve regurgitation, but the pressure gradient across the conduit increases with time, which is the main cause of conduit failure and explantation.  相似文献   
122.

Purpose

To compare the outcomes of partially covered self-expandable metallic stent (SEMS) placement with surgical gastrojejunostomy (GJ) in patients with gastroduodenal obstruction caused by pancreatic cancer.

Methods

The medical records of 107 patients with gastroduodenal obstruction caused by pancreatic cancer who underwent fluoroscopic partially covered SEMS placement (n = 75) or surgical GJ (n = 32) at our institution were reviewed.

Results

The technical (100% vs. 100%; P > 0.999) and clinical (98.7% vs. 96.9%; P = 0.511) success rates were similar between the SEMS and GJ group. The mean gastric outlet obstruction scoring system score was higher in the SEMS group at 1 week after treatment (2.3 ± 0.5 vs. 1.2 ± 0.4; P < 0.001) but was similar between the two groups at 1 month (2.7 ± 0.5 vs. 2.8 ± 0.5; P = 0.242). The median hospital stay was shorter in the SEMS group than in the GJ group (7 vs. 14 days; P < 0.001). The overall complication (22.7% vs. 28.1%; P = 0.547) and reintervention (21.3% vs. 25.0%; P = 0.677) rates were similar between the two groups. The median patency (99 vs. 138 days; P = 0.102) and survival (106 vs. 140 days; P = 0.245) were also similar between the two groups.

Conclusion

The outcomes of partially covered SEMS placement seem to be more favorable than surgical GJ in patients with gastroduodenal obstruction caused by pancreatic cancer.
  相似文献   
123.
ObjectiveThis study aimed to construct a Korean normal elderly brain template (KNE96) using Korean elderly individuals for use in brain MRI studies and to validate it.MethodsWe used high-resolution 3.0T T1 structural MR images from 96 Korean normal elderly individuals (M/F=48/48), aged 60 years or older (M=69.5±6.2 years, F=70.1±7.0 years), for constructing the KNE96 template. The KNE96 template was validated by comparing the registration-induced deformations between the KNE96 and ICBM152 templates using different MR images from 48 Korean normal elderly individuals (M/F=24/24), aged 60 years or older (M=71.5±5.9 years, F=72.8±5.1 years). We used the magnitude of displacement vectors (mag-displacement) and log of Jacobian determinants (log-Jacobian) to quantify the deformation produced during registration process to templates.ResultsThe mag-displacement and log-Jacobian of the registration were much smaller using the KNE96 template than with the ICBM152 template in most brain regions. There was a prominent difference in the significant averaged differences (SADs) of the mag-displacement and log-Jacobian between the KNE96 and ICBM152 at the superior, medial, and middle frontal gyrus, the lingual, inferior, middle, and superior occipital gyrus, and the caudate and thalamus.ConclusionThis study suggests that templates constructed from Asian populations, such as the KNE96, may be more desirable than those from Caucasian populations, like the ICBM152, in computational neuroimaging studies that measure and compare anatomical features of the frontal and occipital lobe, thalamus and caudate.  相似文献   
124.
OBJECTIVE: The purpose of this study was to evaluate the feasibility of transrectal ultrasonography (TRUS) and color Doppler ultrasonography (CDUS) in differentiating malignant from benign distal ureteral obstructions. METHODS: Our study group consisted of 16 malignant distal ureteral obstructions and 12 benign distal ureteral obstructions. The 16 malignant distal ureteral obstructions were transitional cell carcinomas involving the distal ureter. The 12 benign distal ureteral obstructions consisted of benign strictures (n = 4), ureteral edema after stone passage (n = 3), tuberculosis (n = 2), a fibroepithelial polyp (n = 1), amyloidosis (n = 1), and a hematoma (n = 1). Findings from gray scale transabdominal ultrasonography, gray scale TRUS, CDUS, and duplex Doppler imaging were retrospectively evaluated. RESULTS: Gray scale transabdominal ultrasonography and TRUS showed no specific difference between malignant and benign distal ureteral obstructions. On CDUS, malignant distal ureteral obstructions showed dotlike blood flow in 5, moderately increased blood flow in 9, and markedly increased blood flow in 2; and benign distal ureteral obstructions showed absence of blood flow in 5 and dotlike blood flow in 7. Flow spectra could be obtained in 12 malignant distal ureteral obstructions, and they showed arterial waveforms. Duplex Doppler imaging was not tried in 4 malignant distal ureteral obstructions. In 7 benign distal ureteral obstructions with dotlike blood flow, flow spectra could not be obtained. CONCLUSIONS: Moderately or markedly increased blood flow within a ureteral mass on CDUS and an arterial waveform within a ureteral mass on duplex Doppler imaging may be helpful in differentiating malignant from benign distal ureteral obstructions.  相似文献   
125.
126.

Purpose

[18F]AV-1451 is a positron emission tomography (PET) radioligand for detecting paired helical filament tau. Our aim was to estimate the radiation dose of [18F]AV-1451 in humans.

Procedures

Whole-body PET scans were acquired for six healthy volunteers (three male, three female) for 128 min after injection of [18F]AV-1451 (268?±?31 MBq). Radiation doses were estimated using the OLINDA/EXM software.

Results

The estimated organ doses ranged from 7.81 to 81.2 μSv/MBq. The critical organ for radiation burden was the liver. Radiation doses to the reproductive and blood-forming organs were 14.15, 8.43, and 18.35 μSv/MBq for the ovaries, testes, and red marrow, respectively. The mean effective dose was 22.47?±?3.59 μSv/MBq.

Conclusions

A standard single injection of 185 MBq (5 mCi) results in an effective dose of 4.7 mSv in a healthy subject. Therefore, [18F]AV-1451 could be used in multiple PET scans of the same subject per year.
  相似文献   
127.
128.
The outcome of hepatitis B virus (HBV) infection can be affected by host immune factors. Interleukin-18 (IL-18) was originally discovered as an interferon-γ-inducing factor and plays a critical role in immune response. We assessed the association between the clearance of HBV infection and single-nucleotide polymorphisms (SNPs) in the IL-18 gene. Between March 2002 and December 2004, a total of 1,050 Korean subjects were enrolled in the study and divided into two groups: (1) the HBV spontaneous recovery group (n = 320) and (2) the chronic HBV carrier group (n = 730). We analyzed SNPs at four polymorphic sites in the IL-18 gene at positions ?667G>T, ?148G>C, +8925C>G, and +13925A>C. We observed that the subjects bearing the IL-18 ?148C allele [odds ratio (OR), 0.25; confidence interval (CI), 0.09–0.68; P = 0.01], the +8925G allele (OR, 0.36; CI, 0.15–0.88; P = 0.02), and the +13925C allele (OR, 0.25; CI, 0.13–0.82; P = 0.01) were significantly associated with HBV clearance in a recessive model. This study indicates that the ?148C, +8925G, and +13925C alleles of the IL-18 gene are likely associated with HBV clearance in a Korean population.  相似文献   
129.
There are worldwide concerns regarding the potential adverse effect of melamine. This study investigated the potential effects of melamine on pregnant dams and embryo‐fetal development in Sprague–Dawley rats following maternal exposure on gestational days (GD) 6–20. Melamine was administered to pregnant rats by gavage at doses of 0, 200, 400 and 800 mg kg?1 per day (n = 8–10 for each group). All dams were subjected to a Caesarean section on GD 21 and their fetuses were examined for morphological abnormalities. With administration of melamine at 800 mg kg?1 per day, maternal toxicity manifested as increased incidences of clinical signs and death, lower body weight gain and food intake, and increases in heart, adrenal gland and kidney weights. Histopathological examinations revealed an increase in incidences of congestion, tubular necrosis/degeneration, crystals, casts, inflammatory cells in tubules, tubular dilation and tubular hyaline droplets in the maternal kidneys, while fetal kidneys (one fetus/litter) did not show any histopathological changes. Developmental toxic effects included a decrease in fetal weight, an increase in the incidence of skeletal variations and a delay in fetal ossification. No treatment‐related maternal or developmental effects were observed at doses ≤400 mg kg?1 per day. These results show that 15‐day repeated oral dosing of melamine is embryo‐/fetotoxic at a maternotoxic dose, but not teratogenic in rats. The no‐observed‐adverse‐effect level of melamine for pregnant dams and embryo‐fetal development is considered to be 400 mg kg?1 per day. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
130.
Kim JH  Kim MH  Jo DH  Yu YS  Lee TG  Kim JH 《Biomaterials》2011,32(7):1865-1871
The pathological angiogenesis in the retina is the major cause of vision loss at all ages. In particular, retinopathy of prematurity (ROP) is a leading cause of blindness in children. This study investigated whether gold nanoparticle (GNP) could inhibit retinal neovascularization in the animal model of ROP. Intravitreal injection of GNP significantly inhibited retinal neovascularization in the mouse model of ROP. In addition, GNP effectively suppressed VEGF-induced in vitro angiogenesis of retinal microvascular endothelial cells including proliferation, migration and capillary-like networks formation. GNP blocked VEGF-induced auto-phosphorylation of VEGFR-2 to inhibit consequently ERK 1/2 activation. GNP never affected on the cellular viability of retinal microvascular endothelial cells and induced no retinal toxicity. Our data suggest that GNP could be a potent inhibitor to retinal neovascularization without retinal toxicity. Furthermore, GNP could be extensively applied to variable vaso-proliferative retinopathies mediated by VEGF.  相似文献   
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