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21.
This study examined the extent to which racial disparities in service utilization exist in veterans (VA) and non-VA health care systems. An observational study design was used with a nationally representative sample of veterans. Logistic regression models were constructed using sociodemographic characteristics, health insurance and benefits, and health status as predictors of health service use in both VA and non-VA health care systems. A population weighted sample of 19,270 veterans from the 2001 National Survey of Veterans was used, which included 17,004 (88.24 %) White, 1,864 (9.15 %) African American, 414 (2.15 %) Native American/Alaskan Native, and 87 (0.45 %) Asian American/Pacific Islander veterans. Results showed that use of the VA health care system was not associated with race, but was associated with VA disability compensation, lack of private health insurance, and greater health care need. Contrarily, in non-VA healthcare systems, veterans who were racial minorities, less educated, and without private health insurance were less likely to use services. Together, these findings demonstrate the socioeconomic context in which health disparities exist and suggest the influence of health insurance on racial disparities in service utilization.  相似文献   
22.

Background and Purpose

This study was aimed at using proximity ligation assay (PLA) followed by enzyme-linked immunosorbent assay (ELISA) to identify serum biomarkers that predict treatment response and survival for patients with esophageal squamous cell carcinoma (ESCC) undergoing neoadjuvant concurrent chemoradiotherapy (CCRT) followed by esophagectomy.

Methods

Seventy-nine patients with ESCC receiving CCRT of taxane-based/5-fluorouracil-based chemotherapy and 40 Gy followed by surgery were enrolled. Serum samples were collected before and <1 month after CCRT. Fifteen biomarkers were analyzed using PLA. Biomarkers significantly correlating with pathological response/survival were verified by ELISA. Associations of the serum level of biomarkers and clinical factors with pathological response, disease-free survival (DFS), and overall survival (OS) were evaluated by analysis of variance and log-rank tests.

Results

Thirty patients had complete response (38 %), 37 had microscopic residual disease (47 %), and 12 had macroscopic residual disease (15 %). With a median follow-up of 52.8 months, the median DFS was 43 months. Among the 15 biomarkers screened by PLA, vascular endothelial growth factor (VEGF)-A and transforming growth factor (TGF)-β1 were significantly associated with pathological response and/or DFS. These biomarkers were further analyzed by ELISA to confirm initial biomarker findings by PLA. After ELISA of these two markers, only VEGF-A levels were significantly correlated with pathological response. On multivariate analysis, patients with combined high pre-CCRT VEGF-A and TGF-β1 levels (greater than or equal to the median), independent of pathological response, had significantly worse DFS (11 months vs. median not reached; p = 0.007) and OS (16 vs. 46 months; p = 0.07).

Conclusions

Pre-CCRT serum VEGF-A and TGF-β1 levels may be used to predict pathological response and survivals for ESCC patients receiving combined-modality therapy.  相似文献   
23.
Tai YH  Wang YH  Tsai RY  Wang JJ  Tao PL  Liu TM  Wang YC  Wong CS 《Pain》2007,129(3):343-354
The present study was undertaken to examine the effect of amitriptyline on the antinociceptive effect of morphine and its underlying mechanisms in regulating glutamate transporters trafficking in morphine-tolerant rats. Long-term morphine infusion induced antinociceptive tolerance and down-regulation of glutamate transporters (GTs), GLAST, GLT-1, and EAAC1, expression in the rat spinal cord dorsal horn. Acute amitriptyline treatment potentiated morphine’s antinociceptive effect, with a 5.3-fold leftward shift of morphine’s dose–response curve in morphine-tolerant rats, and this was associated with GLAST and GLT-1 trafficking onto the cell surface. Similar to our previous studies, morphine challenge (10 μg/10 μl, i.t.) significant by increased the excitatory amino acids (EAAs) aspartate and glutamate level in the CSF dialysates of morphine-tolerant rats. Acute amitriptyline treatment not only suppressed this morphine-evoked EAA release, but further reduced the EAA concentration than baseline level. Furthermore, long-term morphine infusion up-regulated PKA and PKC protein expression in the spinal cord dorsal horn, while amitriptyline inhibited the increase in expression of phospho-PKA, PKCα, PKCβII, and PKCγ. In morphine-tolerant rats, acute treatment with PKA inhibitor H89 and PKC inhibitor Gö6805 attenuated morphine tolerance and the morphine-induced CSF glutamate and aspartate elevation, and induced trafficking of GLAST and GLT-1 from cytosol onto the cell surface. These results show that acute amitriptyline treatment preserved morphine’s antinociceptive effect in morphine-tolerant rats; the mechanisms may be involved in inhibition of phospho-PKA and PKC expression, and thus inducing the GLAST and GLT-1 trafficking onto glial cell surface which enhances the EAA uptake from the synaptic cleft and reduces EAA concentration in the spinal CSF.  相似文献   
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Successful renal transplantation (RT) improves quality of life and patient survival. Advances in immunosuppressants for RT have improved the prevention and treatment of acute rejection as well as reduced the risk of chronic graft damage, but immunodeficiency may render patients vulnerable to opportunistic infections. We conducted this study to compare the difference in tuberculosis (TB) infection rates between a single institution and a national database of RT recipients in Taiwan. There were 153 patients with TB (3.2%) among 4,835 RT recipients in the database during the period 2000–2009, with a higher prevalence of men (P = .018) and diabetes patients (P = .029). In our institution's registry, 33 patients (2.7%) developed 35 episodes of TB infection among 1,209 RT recipients, but there were no significant differences in general characteristics among different subgroups. Interestingly, the use of cyclosporine was significantly more frequent in RT recipients with TB than in those without in both the national database and in our institution. In contrast, TB infection was negatively correlated with the use of tacrolimus (TAC) and mycophenolate (MPA). RT recipients with TB infection had poor survival (P = .0013) and low graft survival (P = .0003). Taken together, analyses of the national database and the RT patients in our institution revealed that the use of long-term cyclosporine-based immunosuppressive agents was associated with a greater risk of developing post-transplantation TB compared with that of other immunosuppressive agents, but the chronicity and accumulation effect of TAC and MPA should be observed despite the negative correlation found herein. In conclusion, post-transplantation TB is a serious health threat and one of the major causes of death among RT recipients, and a high index of suspicion to ensure early diagnosis and prompt initiation of treatment for TB is crucial. The use of optimal immunosuppressive agents to minimize acute rejection, monitoring of high-risk recipients, prompt diagnosis, and appropriate treatment are required to manage TB infection in endemic areas such as Taiwan.  相似文献   
28.

Introduction

Patient survival among kidney transplant (KTx) recipients has improved remarkably in the past decades. The most common causes of death are cardiovascular disease in the West; in Taiwan, the answer remains uncertain.

Methods

From 1983 to 2012, KTx patients who underwent transplantation and were followed at our hospital were recruited for the study. For comparison, patients were stratified according to the transplant time as group 1, 1983–1989 (the initial era); group 2, 1990–1998 (the cyclosporine era); and group 3, 1999–2012 (the modern era, in which tacrolimus and mycophenolate mofetil were available).

Results

A total of 520 KTx patients (male:female ratio of 285:235) were performed in our hospital during the study period. A progressive improvement in patient survival rates (P < .0001) was noted among the 3 groups. At a mean follow-up duration of 9.55 ± 8.20 years, 83 recipients had died. Overall, the most common cause of death was infection (44.6%), followed by cardiovascular disease (21.7%), malignancy (12.0%), and hepatic failure (10.8%). Infection was the main cause of death in groups 1 and 2 (44.1% and 52.6%, respectively) but not in Group 3 (18.2%), although this trend did not reach statistical significance. Death owing to cardiovascular diseases became the most common cause of death (27.3%) in the modern era (group 3).

Conclusion

The pattern of mortality among Taiwanese KTx patients has changed over the past 30 years. Infection is no longer the commonest cause of death.  相似文献   
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