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11.
X Zavitsanos A Hatzakis E Kaklamani A Tzonou N Toupadaki C Broeksma J Chrispeels H Troonen S Hadziyannis C C Hsieh 《Cancer research》1992,52(19):5364-5367
Stored sera from 181 Greek patients with hepatocellular carcinoma (HCC), 35 patients with metastatic liver cancer, and 416 hospital controls with diagnoses other than malignant neoplasm or liver disease were examined with first and second generation hepatitis C virus (HCV) enzyme immunoassays as well as with five HCV supplemental assays based on structural and nonstructural HCV peptides. Second generation HCV enzyme immunoassays were more sensitive than first generation assays. However, both assays had suboptimal specificity using the standard reactivity criterion (absorbance of sample to cutoff greater than or equal to 1.0). Specificity was improved by centrifugation and by using a sample's optical density to cutoff ratio greater than or equal to 3.0 or supplemental assays; in this instance the prevalence of antibodies to HCV was 13.3% (24 of 181), 0 (0 of 35), and 1.4% (6 of 416) in HCC, metastatic liver cancer, and hospital controls, respectively. A similar estimation of prevalence of antibody to HCV in HCC (12.5% or 4 of 32) was obtained when the recombinant immunoblot assay, second generation, was used to screen a random sample of HCC patients. The relative risk linking HCV to HCC was estimated as 10.4 (95% confidence interval, 4.2-26.0; P less than 0.0001). These data suggest that the prevalence of antibodies to HCV in HCC using stored sera has been previously overestimated even though the evidence of a causal association of HCV with HCC persists. 相似文献
12.
K L Davis L E Hollister A A Mathé B M Davis A B Rothpearl K F Faull J Y Hsieh J D Barchas P A Berger 《The American journal of psychiatry》1981,138(12):1555-1562
The authors performed dexamethasone suppression tests (DST), TRH infusions, 72-hour urine collections, and lumbar punctures on a group of male depressed patients. Approximately 60% of the patients were DST positive and 33% had a blunted TSH response. Two biologic variables, the 8 a.m. postdexamethasone cortisol and the postprobenecid CSF 5-hydroxyindoleacetic acid (5-HIAA), accounted for over half of the variance in the behavioral measure, the Hamilton score. Plasma cortisol elevation was associated with high 3-methoxy-4-hydroxyphenyl glycol (MHPG) excretion; TSH blunting was associated with low urinary MHPG excretion. Comprehensive biologic measures showed certain significant interrelationships and correlations with the severity of depression. 相似文献
13.
M. Depré D. J. Margolskee A. Van Hecken J. S. Y. Hsieh A. Buntinx P. J. De Schepper J. D. Rogers 《European journal of clinical pharmacology》1992,43(4):431-433
Summary The disposition of the enantiomers of MK-571 (MK-0679 and L-668,018) following single i. v. doses of MK-571 (L-660,711) was studied in a three way cross-over study in 12 healthy male volunteers. Each volunteer received 75 mg, 300 mg and 600 mg i. v. doses of MK-571 at weekly intervals.The disposition of both enantiomers appeared dose-dependent, since the AUC increased disproportionately faster than the dose. The dose dependency was much more pronounced for L-668,018: its AUC increased 6-fold from the 75 to the 300 mg dose, 16-fold from 75 to 600 mg and 2.7 fold from 300 to 600 mg. For MK-0679, the corresponding increases in AUC were 4.8-, ll-, and 2.3 fold. Regardless of dose, the elimination of L-668,018 was more rapid than that of MK-0679.The disposition of MK-0679 needs to be investigated independently to detect any potential influence of L-668,018 on its disposition. 相似文献
14.
Chung-Ho Chen Chao-San Chang Chi-Hsin Hsieh Yu-Chuan Tseng Yee-Shyong Shen I-Yueh Huang Chia-Fu Yang Chun-Ming Chen 《Journal of oral and maxillofacial surgery》2006,64(8):1209-1213
PURPOSE: Various types of temporary implants have been introduced to serve as orthodontic anchorage. The hypothesis of this study is that microimplants of 1.2 mm diameter can be used as orthodontic anchors, and that their success is related to their length. The aim of this study is to determine the incidence of anchor retention after orthodontic force application for moving teeth, and to determine the relationship of microimplant length to retention rate. METHODS: Fifty-nine microimplants (diameter: 1.2 mm) were placed in 29 patients as orthodontic anchorages. After 2 weeks of microimplant placement, a force of 100 to 200 g was loaded with an elastometric chain or NiTi coil spring. Risk factors were characterized as to why a microimplant may fail, and Fisher's exact test was used for statistical analysis. RESULTS: Nine microimplants were removed and the overall success rate was 84.7%. Exploring the causes for failure, we found significant differences between the length of microimplants and success rate; 6 mm was 72.2% and 8 mm was 90.2%. CONCLUSIONS: The results suggest that microimplants are suited as an alternative orthodontic anchorage. We recommend that 8-mm microimplants are preferable to 6-mm. 相似文献
15.
To study the effect of hypotensive agents on intraocular pressure elevation following argon laser iridotomy, 0.5% timolol maleate topically and acetazolamide 125 mg orally were given in 39 eyes, one hour prior to laser iridotomy, with 29 eyes serving as the control. The mean pressure two hours after laser iridotomy was 18.9 +/- 7.2 mmHg in the control group and 12.8 +/- 3.9 mmHg in the pretreated group. Ocular pressure was elevated from the baseline pressure of the prelaser status in two eyes (5%) only in the timolol-acetazolamide treated group and in 16 eyes (55%) in the control group. The pressure elevation two hours after laser iridotomy was significantly less in the timolol-acetazolamide pretreated group. 相似文献
16.
The effect of food on the pharmacokinetics of cefuroxime axetil was studied. Twelve healthy male subjects were included in this study. They were given single oral 500 mg doses of cefuroxime axetil alone or with food based on a balanced two-way crossover design. Plasma cefuroxime concentrations were assayed by the high performance liquid chromatographic method. When the drug was given alone, the area under the curve (AUC) was 15.77 +/- 4.12 mg*h/L, Cmax was 4.20 +/- 1.05 mg/L, Tmax was 2.36 +/- 0.84 h, T1/2 was 1.56 +/- 0.26 h, and Clp/F was 34.13 +/- 10.39 L/h; 45.12 +/- 9.59% of the dose was recovered in the urine within 24 hours, and the renal clearance was 12.58 +/- 4.41 L/h. When the drug was given with food, the corresponding AUC was 23.46 +/- 4.57 mg*h/L, Cmax was 7.10 +/- 1.41 mg/L, Tmax was 2.04 +/- 1.32 h, T1/2 was 1.40 +/- 0.23 h, and Clp/F was 21.93 +/- 5.18 L/h; the 24-hour urinary recovery was 69.33 +/- 6.13% and the renal clearance was 12.58 +/- 2.99 L/h. The above pharmacokinetic parameters obtained from the two regimens were compared by two-way ANOVA corrected for the change-over effect. No significant difference was found for Tmax, T1/2 or renal clearance (p > 0.05). Higher AUC, Cmax, urinary recovery and lower Clp/F values were observed for the regimen with food (p < 0.05). The plasma drug concentrations resulting from the regimen with food were higher throughout the 12-hour sampling period when compared to the regimen without food.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
17.
The steady-state kinetics of the creatine kinase reaction in rabbit skeletal muscle in vivo was investigated using inversion and saturation magnetization transfer techniques. Both techniques determined the forward rate of this reaction (creatine phosphate ATP) as approximately 0.3 s-1. This corresponds to a flux of 10 mumol creatine phosphate/s/g muscle. The saturation transfer technique underestimated the reverse reaction by approximately 56%. This result is likely due to the participation of ATP in other interactions in skeletal muscle not involving creatine phosphate. 相似文献
18.
Yu-Te Wu Yen-Chun Chou Wan-Yuo Guo Tzu-Chen Yeh Jen-Chuen Hsieh 《Magnetic resonance in medicine》2007,57(1):181-191
The ability to cluster different perfusion compartments in the brain is critical for analyzing brain perfusion. This study presents a method based on a mixture of multivariate Gaussians (MoMG) and the expectation-maximization (EM) algorithm to dissect various perfusion compartments from dynamic susceptibility contrast (DSC) MR images so that each compartment comprises pixels of similar signal-time curves. This EM-based method provides an objective way to 1) delineate an area to serve as the in-plane arterial input function (AIF) of the feeding artery for adjacent tissues to better quantify the relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), and mean transit time (MTT); 2) demarcate regions with abnormal perfusion derangement to facilitate diagnosis; and 3) obtain parametric maps with supplementary information, such as temporal scenarios and recirculation of contrast agent. Results from normal subjects show that perfusion cascade manifests (in order of appearance) the arteries, gray matter (GM), white matter (WM), veins and sinuses, and choroid plexus mixed with cerebrospinal fluid (CSF). The averaged rCBV, rCBF, and MTT ratios between GM and WM are in good agreement with those in the literature. Results from a patient with cerebral arteriovenous malformation (CAVM) showed distinct spatiotemporal characteristics between perfusion patterns, which allowed differentiation between pathological and nonpathological areas. 相似文献
19.
Jong-Kai Hsiao Ming-Fong Tai Hung-Hao Chu Shin-Tai Chen Hung Li Dar-Ming Lai Sung-Tsang Hsieh Jaw-Lin Wang Hon-Man Liu 《Magnetic resonance in medicine》2007,58(4):717-724
The purpose of this work was to evaluate the efficacy of labeling human mesenchymal stem cells (hMSCs) by ionic superparamagnetic iron oxide (SPIO) without a transfection agent and verifying its capability to be detected with clinical 1.5 T magnetic resonance (MR) at the single-cell level. Human hMSCs were incubated for 24 h with an ionic SPIO, Ferucarbotran. The labeling efficiency of hMSCs was determined by iron content measurement spectrophotometrically, and the influence of labeling on cell behavior was ascertained by examination of cell viability using the trypan blue exclusion method, cell proliferation analysis using MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, mitochondrial membrane potential (MMP) change, differentiation capacity, and reactive oxygen species (ROS) production measured by dichlorofluorescein diacetate (DCFDA) fluorescent probe. Labeled hMSCs were scanned under 1.5 T MRI with three-dimensional (3D) and two-dimensional (2D) T(2)-weighted gradient echo (GRE) pulse sequences. Human hMSC labeling without transfection agent was efficient. The iron content in hMSCs was 23.4 pg Fe/cell. No significant change was found in viability, proliferation, MMP change, ROS production, or differentiation capacity. About 45.2% of the hMSCs could be detected using 1.5 T MRI at the single cell level with 3D GRE and four repetitions. 相似文献
20.
BACKGROUND AND PURPOSE: Early identification of predictive factors relevant to functional outcomes for stroke patients is important to the establishment of an effective continuing care program. The objective of this study was to identify the predictive factors related to functional outcome at discharge after stroke rehabilitation therapy. METHODS: 105 first-time stroke patients admitted to the inpatient rehabilitation department of a university-based medical center were recruited for this prospective study. The functional outcomes of the patients were assessed at admission and at discharge using the Functional Independence Measure (FIM). Severity of stroke was determined using the Canadian Neurological Scale (CNS). Age, gender, side of hemiplegia (SIDE), type of stroke (TYPE), onset to admission interval (OAI), and length of rehabilitation stay (LORS) were also included as predictor variables. RESULTS: The mean (+/- SD) FIM score at discharge (76.6 +/- 26.4) correlated strongly (r = 0.78, p < 0.001) with the admission FIM score (56.3 +/- 24.1), moderately (r = 0.46, p < 0.001) with the admission CNS score (6.1 +/- 2.2), negatively (r = -0.38, p < 0.001) with age (63.2 +/- 12.3 years), negatively (r = -0.26, p = 0.009) with OAI (24.2 +/- 16.0 days), and negatively (r = -0.29, p = 0.002) with LORS (34.7 +/- 16.8 days). Stepwise regression analyses indicated that admission FIM score, age, and admission CNS score were the strongest predictors of functional outcome and accounted for 66% of the total variation in discharge FIM total score. The admission FIM score was the best predictor and accounted for 61% of the variation. CONCLUSIONS: The findings of this study imply that the admission FIM scores for inpatients receiving stroke rehabilitation can be used to predict functional outcomes at discharge from hospital. 相似文献