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91.
The effect of lycopene supplementation on the antioxidant system was investigated by analyzing lipid peroxide levels, glutathione contents, and antioxidant enzyme activities in Mongolian gerbils fed a high fat diet. Gerbils were fed on each experimental diet for 6 weeks; normal diet (NC), normal diet with 0.05% lycopene (NL), high fat diet (HF), and a high fat diet with 0.05% lycopene (HFL). Dietary supplementation of lycopene increased hepatic lycopene level in gerbils fed a normal or high fat diet (P < 0.05). Liver and erythrocyte concentrations of lipid peroxide increased in gerbils fed a high fat diet, whereas lycopene supplementation decreased liver and erythrocyte concentrations of lipid peroxide (P < 0.05). Hepatic total glutathione content was higher in the NL group than that in the NC group (P < 0.05). Total antioxidant status in plasma increased following lycopene supplementation compared with that of the non-lycopene supplemented groups (P < 0.05). Hepatic catalase activity increased following dietary lycopene supplementation (P < 0.05). Superoxide dismutase activity in liver remained unchanged with lycopene supplementation, but erythrocyte superoxide dismutase activity increased in NL group compared with NC group (P < 0.05). Glutathione-S-transferase activity increased in the NL group compared to NC group (P < 0.05). Liver and erythrocyte glutathione peroxidase activity increased significantly in the NL group compared to that in the HF group (P < 0.05). Liver glutathione reductase activity was higher in the NL group than that in the NC group (P < 0.05). These results suggest that lycopene supplementation may be efficient for preventing chronic diseases induced by oxidative stress related to high fat diet.  相似文献   
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94.
Single-photon emission computed tomography/computed tomography (SPECT/CT) has emerged during the past decade as a means of correlating anatomical information from CT with functional information from SPECT. The integration of SPECT and CT in a single imaging device facilitates anatomical localization of the radiopharmaceutical to differentiate physiological uptake from that associated with disease and patient-specific attenuation correction to improve the visual quality and quantitative accuracy of the SPECT image. The first clinically available SPECT/CT systems performed emission-transmission imaging using a dual-headed SPECT camera and a low-power x-ray CT subsystem. Newer SPECT/CT systems are available with high-power CT subsystems suitable for detailed anatomical diagnosis, including CT coronary angiography and coronary calcification that can be correlated with myocardial perfusion measurements. The high-performance CT capabilities also offer the potential to improve compensation of partial volume errors for more accurate quantitation of radionuclide measurement of myocardial blood flow and other physiological processes and for radiation dosimetry for radionuclide therapy. In addition, new SPECT technologies are being developed that significantly improve the detection efficiency and spatial resolution for radionuclide imaging of small organs including the heart, brain, and breast, and therefore may provide new capabilities for SPECT/CT imaging in these important clinical applications.  相似文献   
95.
PURPOSE: To develop a system for texture-based quantification of emphysema on high-resolution computed tomography (HRCT) and to compare it with density-based quantification in correlation with pulmonary function test (PFT). MATERIALS AND METHODS: Two hundred sixty-one circular regions of interest (ROI) with 16-pixel diameter [66 ROIs representing typical area of normal lung; 69 representing bronchiolitis obliterans (BO); 64, mild emphysema (ME); and 62, severe emphysema (SE)] were used to train the automated classification system based on the Support Vector Machine classifier and on variable texture and shape features. An automated quantification system was developed with a moving ROI in the lung area, which classified each pixel into 4 categories. To validate the system, the HRCT and standard-kernel-reconstructed volumetric CT data of 39 consecutive patients with emphysema were included. Using this system, the whole lung area was evaluated, and the area fractions of each class were calculated (normal lung%, BO%, ME%, SE%, respectively). The emphysema index (EI) of texture-based quantification was defined as follows: (0.3 x ME% + SE%) (TEI). EIs from density-based quantification with a threshold of -950 Hounsfield Units, were measured on both HRCT (DEI_HR_2D) and on volumetric CT (DEI_standard_3D). The agreement between TEI, DEI_HR_2D, and DEI_standard_3D was assessed using interclass correlation coefficients (ICC). Correlation of the results on the TEI with the PFT results was compared with the results of the DEI_standard_3D and the DEI_HR_2D with Spearman's correlation test. To evaluate the contribution of each texture-based quantification lesion (BO%, ME%, SE%) on PFT, multiple linear regression analysis was performed. RESULTS: The calculated TEI (19.71% +/- 17.98%) was well correlated with the DEI_standard_3D (19.42% +/- 14.30%) (ICC = 0.95), whereas the ICC with DEI_HR_2D (37.22% +/- 9.42%) was 0.43. TEI showed better correlation with PFT than DEI_standard_3D or DEI_HR_2D did [R = 0.71 vs. 0.67 vs. 0.61 for forced expiratory volume in 1 second (FEV(1))/forced vital capacity (FVC); 0.54 vs. 0.50 vs. 0.43 for diffusing capacity (DLco), respectively]. Multiple linear regression analysis revealed that the BO% and SE% areas were independent determinants of FEV(1)/FVC, whereas the ME% and the SE% were determinants of DLco. CONCLUSION: Texture-based quantification of emphysema using an automated system showed better correlation with the PFT results than density-based quantification. Separate quantification of the BO, ME, and SE areas showed a different contribution of each component to the FEV(1)/FVC and the DLco. The proposed system can be successfully used for detailed regional and global evaluation of lung lesions on HRCT scanning for emphysema.  相似文献   
96.

Objective  

We compared the electrode positions of subthalamic nucleus (STN) deep brain stimulation (DBS) estimated at the immediate postoperative period with those estimated 6 months after surgery.  相似文献   
97.

Background

Few studies assessing the functional change of each kidney following warm ischaemia after partial nephrectomy are available.

Objectives

Our aim was to identify the effects of the warm ischaemic time (WIT) on renal function after partial nephrectomy under the pneumoperitoneum.

Design, setting, and participants

Forty-four consecutive patients who underwent laparoscopic partial nephrectomy (LPN) or robot-assisted partial nephrectomy (RAPN) from June 2008 to May 2009 for a single cT1 renal tumour were included in this prospective protocol.

Measurements

Technetium Tc 99m-diethylenetriaminepentaacetic acid (Tc 99m-DTPA) renal scintigraphy was used to determine the glomerular filtration rate (GFR) of both kidneys and each kidney individually. Tc 99m-DTPA GFR was performed preoperatively and 3 mo postoperatively. In addition, we analysed Tc 99m-DTPA scintigraphy GFR regionally in the healthy areas of the affected kidney.

Results and limitations

Patients with WIT >28 min had a significantly greater decrease in the GFR of the affected kidney (p = 0.031). The GFR of the affected kidney showed a significant decrease perioperatively (46.4 ± 14.3 to 37.9 ± 11.9 ml/min per 1.73 m2; p = 0.003). The functional change of the nonaffected kidney showed an increasing trend (47.5 ± 13.8 to 51.4 ± 14.3 ml/min per 1.73 m2), although it was not statistically significant (p = 0.103). Regional Tc 99m-DTPA GFR of both affected kidney and nonaffected kidney showed no significant differences perioperatively (6.3 ± 1.8 to 6.1 ± 1.9 ml/min per 1.73 m2; p = 0.641; 6.6 ± 1.9 to 7.1 ± 2.0 ml/min per 1.73 m2; p = 0.200). On multivariate analysis, preoperative GFR, resected volume of marginal healthy tissue, and WIT were independent predictors for functional reduction of the affected kidney (p < 0.05). The study was limited by small numbers and short follow-up periods.

Conclusions

Stationary overall renal function after LPN or RAPN is masked possibly by functional compensation of the contralateral healthy kidney. The damage of the affected kidney estimated by scintigraphy occurs when WIT exceeds 28 min during partial nephrectomy under the pneumoperitoneum.  相似文献   
98.
To gain beneficial effects in the management of high-risk prostate cancer, an integrated approach that combines local therapy and androgen deprivation therapy (ADT) was used. We compared biochemical responses between primary cryosurgical ablation of the prostate (CSAP) combined with prolonged ADT and radiation combined with ADT, which is the established modality in high-risk disease. A total of 33 high-risk patients received CSAP combined with ADT for 3 months before and up to 24 months after treatment. This patient group was matched with another 33 patients who had undergone three-dimensional conformal radiation therapy (3D-CRT) with the same protocol for ADT. Biochemical recurrence (BCR) was assessed by the American Society for Therapeutic Radiation Oncology (ASTRO) definition, the Phoenix definition and a prostate-specific antigen (PSA) cutoff of 0.5 ng mL^-1. Median follow-up was 61.0 ± 11.9 months for the CSAP + ADT group and 86.0±15.8 months for the 3D-CRT + ADT group. In the CSAP group, major complications including rectourethral fistula and incontinence were not noted. In the CSAP + ADT group, 57.0% had BCR using the ASTRO definition, 21.2% using the Phoenix definition and 54.5% using a PSA cutoff of 0.5 ng mL^-1. In the 3D-CRT + ADT group, 54.5%, 21.2% and 54.5% had BCR using the ASTRO, Phoenix and PSA definition, respectively. In the CSAP + ADT group, the BCR-free survival (BRFS) was 54 ± 10 months using the ASTRO definition, 65 ± 5 months using the Phoenix definition and 51 ± 4 months using a PSA cutoff of 0.5 ng mL-1. In the 3D-CRT + ADT group, the BRFS was 68 ± 12, 93 ± 19 and 70 ± 18 months using the ASTRO, Phoenix and PSA definition, respectively. By the log-rank test, the BRFS values for each group were not statistically different. This intermediate-term result indicated that primary CSAP combined with prolonged ADT offers a parallel biochemical response compared with radiotherapy in high-risk prostate cancer.  相似文献   
99.
Background: The authors determined whether desflurane altered myocardial excitation-contraction coupling and electrophysiologic behavior in the same manner as isoflurane and sevoflurane.

Methods: The effects of desflurane on isometric force in guinea pig ventricular papillary muscles were studied in modified standard and in 26 mm K+ Tyrode solution with 0.1 [mu]m isoproterenol. Desflurane effects on sarcoplasmic reticulum Ca2+ release were also determined by examining its actions on rat papillary muscles, guinea pig papillary muscles in low-Na+ Tyrode solution, and rapid cooling contractures. Normal and slow action potentials were recorded using a conventional microelectrode technique. Ca2+ and K+ currents of guinea pig ventricular myocytes were examined.

Results: Desflurane (5.3% and 11.6%) decreased peak force to approximately 70% and 40% of the baseline, respectively, similar to the effects of equianesthetic isoflurane concentrations. With isoproterenol in 26 mm K+ Tyrode solution, desflurane markedly depressed late peaking force and modestly depressed early peak force. The rested state contractions of rat myocardium or guinea pig myocardium in low-Na+ Tyrode solution were modestly depressed, whereas rapid cooling contractures were virtually abolished after desflurane administration. Desflurane significantly prolonged the action potential duration. Desflurane reduced L-type Ca2+ current and the delayed outward K+ current but did not alter the inward rectifier K+ current.  相似文献   

100.
Fifteen skeletally immature patients with double major adolescent idiopathic scoliosis with large lumbar curves and notable L4 and L5 coronal plane obliquity were retrospectively studied. Seven patients who underwent anterior release and fusion of the lumbar curve with segmental anterior instrumentation and subsequent posterior instrumentation ending at L3 were compared with eight patients treated with anterior release and fusion without anterior instrumentation followed by posterior instrumentation to L3 or L4. At 4.5 years follow-up (range 2.5-7 years), curve correction, coronal balance and fusion rate were not statistically different between the two groups; however, the group with anterior instrumentation had improved coronal plane, near normalangulation in the distal unfused segment compared with the group without anterior instrumentation. In cases involving severe lumbar curvatures in the context of double major scoliosis, when as a first stage anterior release is chosen, the addition of instrumentation appears to restore normal coronal alignment of the distal unfused lumbar segment, and may in certain cases save a level compared with traditional fusions to L4.  相似文献   
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