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81.
Jujube (Ziziphus jujuba Mill.) has long been used for human consumption and medicinal purposes in China. It is recommended for some diseases in which radical species are produced as a result of oxidative stress. However, the systematic study on the antioxidant capacities of various tissues of jujube is still lacking. In order to address this, various tissues of three jujube varieties were characterized with respect to their antioxidant capacities and antioxidant compounds such as flavonoid, ascorbic acid, anthocyanin and phenolic. Antioxidant capacity was measured using the DPPH (2,2-diphenyl-1-picrylhydrazyl) and FRAP (ferric-reducing antioxidant power) assays. The phenolic acids were analyzed by high-performance liquid chromatography (HPLC). The results show that the peel of all cultivars has the highest antioxidant capacities, reflecting the highest content of total phenolics, flavonoids, and anthocyanins found in this part. In addition, the predominant phenolic acid in jujube was found to be protocatechuic acid, followed by gallic acid, chlorogenic acid and caffeic acid. The results obtained in this study clearly indicate that Chinese jujube has a significant potential to use as a natural antioxidant agent.  相似文献   
82.
83.
Sato S  Ohhashi W  Ihara H  Sakaya S  Kato T  Ikeda H 《Transfusion》2001,41(9):1107-1113
BACKGROUND: Studies were conducted using samples from early and late-stage HBV-infected persons to determine the pool size at which PCR had better sensitivity than a sensitive HBsAg chemoluminescence immunoassay (CLIA-HBsAg). STUDY DESIGN AND METHODS: HBV seroconversion panels were tested for HBsAg by CLIA and for HBV DNA by nested PCR (95% hit rate: 100 copies/mL); PCR was carried out at various dilutions. HBV serologically positive samples that were detected from the simultaneous screening of 540,161 routine whole-blood donations using CLIA-HBsAg and agglutination assays were also characterized for additional markers of HBV infection. RESULTS: In 9 of 10 HBV seroconversion panels, PCR had better sensitivity than CLIA-HBsAg at dilutions of 1-in-25 or lower. Of 65 CLIA-only confirmed-positive donor samples (agglutination assay-negative), 8 represented early infection, 2 of which were PCR positive at a 1-in-50 dilution but negative at a 1-in-100 dilution. Only 2 of 47 samples from probable late-stage HBV infection that were positive on CLIA only were PCR positive with 0.1-mL sample volume and the S-region primer; the remaining 45 samples required a 1.0-mL sample input and C-region primer for increased PCR positivity. The remaining 10 CLIA-only confirmed-positive donor samples were from HBV vaccine recipients. None of the 12 CLIA- and HBsAg-negative donor samples that were strongly anti-HBc reactive could be detected by PCR at any dilution; all 12 were PCR positive when undiluted, but 4 required a 1.0-mL input volume for PCR positivity. CONCLUSION: For the detection of samples representing early-stage HBV infection, PCR at dilutions of 1-in-25 or lower (equivalent to a pool of < or =25 members) had greater sensitivity than CLIA-HBsAg. In contrast, samples from late-stage HBV infection were detected by PCR only with undiluted samples (0.1-mL or 1.0-mL input volumes), regardless of CLIA-HBsAg reactivity. Therefore, although NAT using minipools of 25 donations or less may be effective for the detection of early-stage HBV infection, it may not be effective for the detection of persistent HBV infection.  相似文献   
84.
The purpose of the study was to validate, in patients, the accuracy of magnetocardiography (MCG) for three-dimensional localization of an amagnetic catheter (AC) for multiple monophasic action potential (MAP) with a spatial resolution of 4 mm2. The AC was inserted in five patients after routine electrophysiological study. Four MAPs were simultaneously recorded to monitor the stability of endocardial contact of the AC during the MCG localization. MAP signals were band-pass filtered DC-500 Hz and digitized at 2 KHz. The position of the AC was also imaged by biplane fluoroscopy (XR), along with lead markers. MCG studies were performed with a multichannel SQUID system in the Helsinki BioMag shielded room. Current dipoles (5mm; 10mA), activated at the tip of the AC, were localized using the equivalent current dipole (ECD) model in patient-specific boundary element torso. The accuracy of the MCG localizations was evaluated by: (1) anatomic location of ECD in the MRI, (2) mismatch with XR. The AC was correctly localized in the right ventricle of all patients using MRI. The mean three-dimensional mismatch between XR and MCG localizations was 6 ± 2 mm (beat-to-beat analysis). The coefficient of variation of three-dimensional localization of the AC was 1.37% and the coefficient of reproducibility was 2.6 mm. In patients, in the absence of arrhythmias, average local variation coefficients of right ventricular MAP duration at 50% and 90% ofrepolarization, were 7.4% and 3.1%, respectively. This study demonstrates that with adequate signal-to-noise ratio, MCG three-dimensional localizations are accurate and reproducible enough to provide nonfluoroscopy dependant multimodal imaging for high resolution endocardial mapping of monophasic action potentials.  相似文献   
85.

Objective

To assess the association between exercise capacity and the risk of major adverse cardiovascular events (MACEs).

Patients and Methods

A symptom-limited exercise tolerance test was performed to assess exercise capacity in 20,590 US veterans (12,975 blacks and 7615 whites; mean ± SD age, 58.2±11.0 years) from the Veterans Affairs medical centers in Washington, District of Columbia, and Palo Alto, California. None had a history of MACE or evidence of ischemia at the time of or before their exercise tolerance test. We established quintiles of cardiorespiratory fitness (CRF) categories based on age-specific peak metabolic equivalents (METs) achieved. We also defined the age-specific MET level associated with no risk for MACE (hazard ratio [HR], 1.0) and formed 4 additional CRF categories based on METs achieved below (least fit and low fit) and above (moderately fit and highly fit) that level. Multivariate Cox models were used to estimate HR and 95% CIs for mortality across fitness categories.

Results

During follow-up (median, 11.3 years; range, 0.3-33.0 years), 2846 individuals experienced MACEs. The CRF-MACE association was inverse and graded. The risk for MACE declined precipitously for those with a CRF level of 6.0 METs or higher. When considering CFR categories based on the age-specific MET threshold, the risk increased for those in the 2 CFR categories below that threshold (HR, 1.95; 95% CI, 1.73-2.21 and HR, 1.41; 95% CI, 1.27-1.56 for the least-fit and low-fit individuals, respectively) and decreased for those above it (HR, 0.77; 95% CI, 0.68-0.87 and HR, 0.57; 95% CI, 0.48-0.67 for moderately fit and highly fit, respectively).

Conclusion

Increased CRF is inversely and independently associated with the risk for MACE. When an age-specific MET threshold was defined, the risk for MACE increased significantly for those below that threshold and decreased for those above it (P<.001).  相似文献   
86.

Purpose

To evaluate the radiation dose reduction, image quality and diagnostic confidence with thoraco-abdominopelvic computed tomography (TACT) using a new organ based dose modulation system (liver dose right index [Liver DRI]), compared to TACT using a standard automatic exposure control adjusting mA according to attenuation.

Methods

A total of 37 patients who had two TACT examinations on 2 different CT scanners, one using standard automatic exposure control (combination of a DoseRight automatic current selection and Z modulation) and one using Liver DRI were included. There were 19 men and 18 women with a mean age of 67.6 ± 11.7 (SD) years (range: 36–85 years) For each patient, volume CT dose index (CTDIvol), size-specific dose estimates (SSDE) and signal-to-noise ratio (SNR) were evaluated at each anatomic level (lung, breast, liver and pelvis area) for each protocol. Two radiologists assessed independently image quality, artifacts and diagnostic confidence.

Results

The radiation dose decreased significantly using Liver DRI compared to standard automatic exposure control on the total scan length, lung, breast and pelvis area, with a significant CTDIvol reduction of 27% (P = 0.0001), 23% (P = 0.0002), 24% (P = 0.0002) and 31% (P = 0.0001), respectively; and a significant SSDE reduction of 23% (P = 0.0001), 28% (P = 0.0001), 23% (P = 0.0002) and 29% (P = 0.0001), respectively. No significant SNR reductions were observed in all measured tissues at the level of the aortic arch, celiac trunk and iliac bifurcation, except in the muscle (P = 0.0013) and fat tissue (P = 0.0052) at the level of the ureteral meatus. No significant differences were noted between both protocols in overall image quality, artifacts and diagnostic confidence with an excellent inter observer agreement between radiologists (Kappa values of 0.83, 0.85 and 0.88, respectively).

Conclusion

Liver DRI organ based dose modulation technique allows significant dose reduction compared to standard automatic exposure control while preserving diagnostic image quality in all thoraco-abdominopelvic areas.  相似文献   
87.
ObjectiveTo investigate the association between the amount and intensity of leisure-time physical activity (LTPA) and the risk of end-stage renal disease (ESRD).MethodsThe study examined a cohort of 543,667 participants aged 20 years and older who participated in a health screening program from January 1, 1996, through December 31, 2017. We identified 2520 individuals undergoing dialysis or who had a kidney transplant by linking participants’ encrypted personal identification with the registry for ESRD with a median follow-up of 13 years. We classified participants into 5 categories measured by metabolic equivalent of tasks. Within each category, we analyzed the effect of moderate- and vigorous-intensity LTPA in reducing risk of ESRD. We used a Cox proportional hazards model to calculate hazard ratios (HRs).ResultsWe observed a dose-response relationship between LTPA and the risk of ESRD. The fully active group had a 12% lower hazard of ESRD compared with the no reported LTPA group (HR, 0.88; 95% CI, 0.80 to 0.98) adjusting for covariates including baseline estimated glomerular filtration rate and proteinuria. Within the same category of LTPA, vigorous-intensity exercise carried a 35% lower HR for ESRD compared with moderate-intensity exercise (HR, 0.65; 95% CI, 0.52 to 0.81). The effect was observed stronger among men, younger participants, and participants with diabetes or hyperlipidemia.ConclusionSustained LTPA (≥ 150 minutes per week), particularly with vigorous intensity, significantly lowered the ESRD risk, even among individuals with comorbidities such as diabetes or hyperlipidemia. This finding suggested that patients with no reported LTPA with cardiovascular risks should engage in more LTPA to lower their risk of ESRD.  相似文献   
88.
ObjectiveTo determine the interrelationship between body mass index (BMI), mode of stress testing (exercise or pharmacological), exercise capacity, and all-cause mortality in patients referred for stress-rest single photon emission computed tomography myocardial perfusion imaging.Patients and MethodsWe evaluated all-cause mortality in 21,638 patients undergoing stress-rest single photon emission computed tomography myocardial perfusion imaging between January 2, 1991, and December 31, 2012. Patients were divided into exercise and pharmacologically tested groups and 9 BMI categories. The median follow-up was 12.8 years (range, 5.0-26.8 years).ResultsIn exercise patients, mortality was increased with both low and high BMI vs patients with a normal referent BMI of 22.5 to 24.9 kg/m2. In pharmacologically tested patients, only low BMI, but not high BMI, was associated with increased mortality vs normal BMI. When exercise and pharmacologically tested groups were compared directly, pharmacologically tested patients manifested a marked increase in mortality risk vs exercise patients within each BMI category, ranging from an approximately 4-fold increase in mortality in those with normal or high BMI to a 12.3-fold increase in those with low BMI values. Similar findings were observed in a cohort of 4804 exercise and 4804 pharmacologically tested patients matched to have similar age and coronary artery disease risk factor profiles. In exercise patients, further risk stratification was achieved when considering both BMI and metabolic equivalent tasks of achieved exercise.ConclusionThe combined assessment of BMI and exercise ability and capacity provides synergistic and marked risk stratification of future mortality risk in patients referred for radionuclide stress testing, providing considerable insights into the “obesity paradox” that is observed in populations referred for stress testing.  相似文献   
89.

Objective

To evaluate the potential independent and combined associations of cognitive and mobility limitations on risk of all-cause mortality in a representative sample of the US older adult population who, at baseline, were free of cardiovascular and cerebrovascular disease.

Patients and Methods

Data from the 1999 to 2002 National Health and Nutrition Examination Survey were used to identify 1852 adults (age, 60-85 years) with and without mobility and/or cognitive limitations. Hazard ratios (HRs) for mortality risk were calculated for 4 mutually exclusive groups: no limitation (group 1 as reference), mobility limitation only (group 2), cognitive limitation only (group 3), both cognitive and mobility limitations (group 4).

Results

Compared with group 1, the adjusted HRs (95% CI) for groups 2, 3, and 4 were 1.72 (1.24-2.38), 2.00 (1.37-2.91), and 2.18 (1.57-3.02), respectively. The mortality risk when comparing group 4 (HR, 2.18) with group 3 (HR, 2.00), however, was not statistically significant (P=.65). Similarly, the mortality risk when comparing group 4 (HR, 2.18) with group 2 (HR, 1.72) was not statistically significant (P=.16).

Conclusion

Although the highest mortality risk occurred in those with both limitations (group 4), this point estimate was not statistically significantly different when compared with those with cognitive or mobility limitations alone.  相似文献   
90.
血管紧张素转换酶抑制剂肾保护作用的有效剂量探讨   总被引:8,自引:0,他引:8  
目的 探讨ACEI肾保护作用的有效剂量。方法 原发性肾小球疾病患者 15 4例。分别实施Captopril、Cilazapril和Enalapril各高、低两个剂量组以及作为对照给予Amlodipine治疗 4个月。治疗前、后每月检测平均动脉压、尿蛋白、尿白蛋白排泄率、尿钠、尿尿素氮和肾功能 ,并检测患者ACE基因表型。结果 ①各组间ACE基因表型分布和蛋白质、食盐摄入量无明显差别 ;②三种ACEI的高、低剂量组间的抗尿蛋白作用和对肾功能的影响无明显差别。结论 对原发性肾小球疾病患者低剂量的ACEI也具备良好的肾保护作用。  相似文献   
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