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71.
The association between stress and health has been well researched in the past; however, comparatively few mediators have been tested to understand the underlying mechanism. With increasing awareness on mental well‐being, this study evaluated the relationship between perceived stress and perceived health and examined mental well‐being as a mediator. Two‐hundred undergraduates aged 21 to 26 years completed the English Perceived Stress Scale, Health Status Questionnaire and Asian Mental Well‐Being Scale that assess perceived stress, perceived health and mental well‐being, respectively. Factor analysis and structural equation modelling on the Perceived Stress Scale replicated the reported two‐factor structure after excluding an insignificant item. Linear multiple regression analyses indicated that perceived stress was negatively associated with perceived health. Results showed that mental well‐being partially mediated the relationship between perceived stress and perceived health, although it is acknowledged that this association could be bidirectional. Findings from the present study suggest that future research could focus on reducing stress and improving mental well‐being to alleviate the effect of stress on health. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
72.
73.
Assessment of aldehyde dehydrogenase in viable cells 总被引:3,自引:4,他引:3
Jones RJ; Barber JP; Vala MS; Collector MI; Kaufmann SH; Ludeman SM; Colvin OM; Hilton J 《Blood》1995,85(10):2742-2746
Cytosolic aldehyde dehydrogenase (ALDH), an enzyme responsible for oxidizing intracellular aldehydes, has an important role in ethanol, vitamin A, and cyclophosphamide metabolism. High expression of this enzyme in primitive stem cells from multiple tissues, including bone marrow and intestine, appears to be an important mechanism by which these cells are resistant to cyclophosphamide. However, although hematopoietic stem cells (HSC) express high levels of cytosolic ALDH, isolating viable HSC by their ALDH expression has not been possible because ALDH is an intracellular protein. We found that a fluorescent aldehyde, dansyl aminoacetaldehyde (DAAA), could be used in flow cytometry experiments to isolate viable mouse and human cells based on their ALDH content. The level of dansyl fluorescence exhibited by cells after incubation with DAAA paralleled cytosolic ALDH levels determined by Western blotting and the sensitivity of the cells to cyclophosphamide. Moreover, DAAA appeared to be a more sensitive means of assessing cytosolic ALDH levels than Western blotting. Bone marrow progenitors treated with DAAA proliferated normally. Furthermore, marrow cells expressing high levels of dansyl fluorescence after incubation with DAAA were enriched for hematopoietic progenitors. The ability to isolate viable cells that express high levels of cytosolic ALDH could be an important component of methodology for identifying and purifying HSC and for studying cyclophosphamide-resistant tumor cell populations. 相似文献
74.
Busch MP; Laycock M; Kleinman SH; Wages JW Jr; Calabro M; Kaplan JE; Khabbaz RF; Hollingsworth CG 《Blood》1994,83(4):1143-1148
Blood donations in the United States have been screened for antibody to human T-lymphotropic virus type I (HTLV-I) by HTLV-I enzyme immunoassay (EIA) since November 1988. Specimens repeatedly found to be reactive by EIA undergo confirmation by supplementary serologic tests. We assessed the accuracy of blood center testing of 994 HTLV-I EIA repeat-reactive specimens in five US blood centers between November 1988 and December 1991. Of 410 confirmed HTLV-I/II donations, 407 (99.3%) were infected with HTLV-I/II, as determined by polymerase chain reaction (PCR) (403 cases) and by repeat serologic testing (4 cases). The three false- positive results occurred in the first year of testing. Of 425 HTLV- indeterminate specimens, 6 (1.4%) were found to be infected by PCR (5 with HTLV-II and 1 with HTLV-I). None of 159 confirmatory test-negative donations was PCR positive. Of HTLV-I/II-seropositive specimens, 80.2% to 95.4% could be typed as HTLV-I or HTLV-II by type-specific serologic assays. These results support recommendations that HTLV-I/II- seropositive donors should be advised that they are infected with HTLV- I, HTLV-II, or HTLV-I/II (depending on results of type-specific assays). HTLV-indeterminate donors should be advised that their results only rarely indicate HTLV infection. HTLV confirmatory test-negative donors should be reassured that they are not infected with HTLV-I or HTLV-II. 相似文献
75.
Sang Kyung Jung Kyung-Ah Kim So Young Ha Hyun Kyo Lee Young Doo Kim Bu Hyun Lee Woo Hyun Paik Jong Wook Kim Won Ki Bae Nam-Hoon Kim June Sung Lee Yoon Jung Jwa 《Clinical and molecular hepatology》2015,21(1):41-48
Background/Aims
This study investigated the antiviral effects of tenofovir disoproxil fumarate (TDF) monotherapy in nucleos(t)ide analogue (NA)-naive and NA-experienced chronic hepatitis B (CHB) patients.Methods
CHB patients treated with TDF monotherapy (300 mg/day) for ≥12 weeks between December 2012 and July 2014 at a single center were retrospectively enrolled. Clinical, biochemical, and virological parameters were assessed every 12 weeks.Results
In total, 136 patients (median age 49 years, 96 males, 94 HBeAg positive, and 51 with liver cirrhosis) were included. Sixty-two patients were nucleos(t)ide (NA)-naïve, and 74 patients had prior NA therapy (NA-exp group), and 31 patients in the NA-exp group had lamivudine (LAM)-resistance (LAM-R group). The baseline serum hepatitis B virus (HBV) DNA level was 4.9±2.3 log IU/mL (mean±SD), and was higher in the NA-naïve group than in the NA-exp and LAM-R groups (5.9±2.0 log IU/mL vs 3.9±2.0 log IU/mL vs 4.2±1.7 log IU/mL, P<0.01). The complete virological response (CVR) rate at week 48 in the NA-naïve group (71.4%) did not differ significantly from those in the NA-exp (71.3%) and LAM-R (66.1%) groups. In multivariate analysis, baseline serum HBV DNA was the only predictive factor for a CVR at week 48 (hazard ratio, 0.809; 95% confidence interval, 0.729-0.898), while the CVR rate did not differ with the NA experience.Conclusions
TDF monotherapy was effective for CHB treatment irrespective of prior NA treatment or LAM resistance. Baseline serum HBV DNA was the independent predictive factor for a CVR. 相似文献76.
Jem Ma Ahn Yong-Han Paik Jun Hee Lee Ju Yeon Cho Won Sohn Geum-Youn Gwak Moon Seok Choi Joon Hyeok Lee Kwang Cheol Koh Seung Woon Paik Byung Chul Yoo 《Clinical and molecular hepatology》2015,21(4):393-397
A 51-year-old male patient with chronic hepatitis B was referred to our hospital due to a 1-cm liver nodule on ultrasonography. Alpha-fetoprotein (AFP) was slightly elevated. The nodule showed prolonged enhancement on dynamic liver magnetic resonance imaging and appeared as a hyperintensity on both diffusion-weighted and T2-weighted imaging. The nodule was followed up because it was small and typical findings of hepatocellular carcinoma (HCC) were not observed in the dynamic imaging investigations. However, liver contrast-enhanced ultrasonography performed 1 month later showed enhancement during the arterial phase and definite washout during the delayed phase. Also, AFP had increased to over 200 ng/mL even though AST and ALT were decreased after administering an antiviral agent. He was presumptively diagnosed as HCC and underwent liver segmentectomy. Microscopy findings of the specimen indicated bile duct adenoma. After resection, the follow-up AFP had decreased to within the normal range. This patient represents a case of bile duct adenoma with AFP elevation mimicking HCC on contrast-enhanced ultrasonography. 相似文献
77.
Ju‐Yeon Cho Won Sohn Yong‐Han Paik Geum‐Youn Gwak Moon Seok Choi Joon Hyeok Lee Kwang Cheol Koh Seung Woon Paik Chan Guk Park 《Journal of viral hepatitis》2020,27(9):951-954
The aim of this study was to investigate the on‐treatment kinetics of quantitative HBsAg during entecavir therapy to predict the treatment period needed to achieve functional cure. From a cohort of 1009 CHB treatment‐naïve patients who were started on entecavir, the kinetics of quantitative HBsAg decline was assessed in 410 patients by a linear mixed model. The difference in the kinetics of quantitative HBsAg was determined based on the HBeAg positivity, HBeAg seroclearance and presence of baseline liver cirrhosis. Among the 410 patients, 213 patients (52.0%) were HBeAg‐positive and 217 patients (66.1%) were male with a median age of 48 years. During a median follow‐up of 53.5 months, the quantitative HBsAg level showed a slow but consistent decrease. The expected log qHBsAg levels as a function of time during entecavir treatment in HBeAg(+) and HBeAg(?) patients were 3.4773‐0.0039 × Months and 3.1853‐0.0036 × Months, respectively. The estimated time to clearance of quantitative HBsAg in our study was greater than 74.1 years in HBeAg‐positive patients and 73.5 years in HBeAg‐negative patients. The calculated time to achieve functional cure is lifelong without regard to HBeAg seroclearance or presence of liver cirrhosis. The mathematical modelling from a long‐term follow‐up of chronic hepatitis B patients on entecavir shows that HBsAg clearance requires decades of treatment. Thus, lifelong therapy is inevitable in entecavir‐treated patients to achieve functional cure. 相似文献
78.
79.
Ja Kyung Kim Dae Won Ma Kwan Sik Lee Yong-Han Paik 《Journal of Korean medical science》2014,29(4):570-575
Transient elastography (TE) has been used as a non-invasive method for liver stiffness measurement (LSM) in patients with chronic liver disease. This study was performed to assess the change of LSM by TE and to assess its clinical usefulness during long-term oral antiviral therapy in patients with chronic hepatitis B (CHB). We retrospectively reviewed 83 CHB patients. The mean interval between two LSM was 411.5 ± 149.5 days. Initial and follow-up LSM was 16.15 ± 12.41 kPa and 11.26 ± 7.36 kPa, respectively (P < 0.001). The degree of regression of liver stiffness was -2.03 ± 0.36% per month. The fibrosis stage classified by LSM value improved in 37 (44.6%) patients during oral antiviral therapy. Of the 30 (36.1%) patients with LSM ≥ 14.1 kPa (cirrhosis) at 1st LSM, 12 (40%) proved to no longer have cirrhosis (≥ 1 decrease in fibrosis stage) at 2nd LSM. LSM significantly decreased in both baseline high (> upper limit of normal [ULN] × 2) and low (≤ ULN × 2) alanine aminotransferase groups during antiviral therapy (P < 0.001; P = 0.001, respectively). Long-term oral antiviral therapy resulted in the improvement of liver stiffness in a substantial portion of patients with CHB. TE may be used a useful clinical tool to assess disease progression in CHB patients.
Graphical Abstract
相似文献80.
Eunsoo Won Seon-Cheol Park Kyu-Man Han Seung-Hwan Sung Hwa-Young Lee Jong-Woo Paik Hong Jin Jeon Moon-Soo Lee Se-Hoon Shim Young-Hoon Ko Kang-Joon Lee Changsu Han Byung-Joo Ham Joonho Choi Tae-Yeon Hwang Kang-Seob Oh Sang-Woo Hahn Yong-Chon Park Min-Soo Lee 《Journal of Korean medical science》2014,29(4):468-484
This paper aims to introduce, summarize, and emphasize the importance of the ''Evidence-Based, Pharmacological Treatment Guideline for Depression in Korea, Revised Edition''. The guideline broadly covers most aspects of the pharmacological treatment of patients in Korea diagnosed with moderate to severe major depression according to the DSM-IV TR. The guideline establishment process involved determining and answering a number of key questions, searching and selecting publications, evaluating recommendations, preparing guideline drafts, undergoing external expert reviews, and obtaining approval. A guideline adaptation process was conducted for the revised edition. The guideline strongly recommends pharmacological treatment considered appropriate to the current clinical situation in Korea, and should be considered helpful when selecting the appropriate pharmacological treatment of patients diagnosed with major depressive disorder. Therefore, the wide distribution of this guideline is recommended. 相似文献