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501.
This study investigates the moderating effects of professional commitment on relationships among burnout, job satisfaction, and turnover intention. Two-hundred fifty-three nurses working in a single medical center in northern Taiwan were sampled and approached, and 238 questionnaires were used. All participants were female and aged <50 years. Moreover, 30.3% of the sample was married. Professional commitment moderated the influence of burnout on job satisfaction, but not the influence of job satisfaction on turnover intention. First, burnout (in terms of reduced personal accomplishment and emotional exhaustion) predicted job satisfaction for high-commitment nurses, but not for low-commitment nurses. Second, job satisfaction predicted turnover intention for both high-commitment and low-commitment nurses.  相似文献   
502.
Reactivation of hepatitis B virus (HBV) after cytotoxic chemotherapy is a serious problem, and it occurred to 41% of breast cancer patients carrying HBV. Previous studies have demonstrated that lamivudine was effective for HBV flare-up during cytotoxic chemotherapy. We aimed to monitor the HBV status of breast cancer patients undergoing chemotherapy with preemptive lamivudine over time. Six breast cancer patients carrying hepatitis B surface antigen (HBsAg) were monitored during chemotherapy, five in the adjuvant setting and one with metastatic disease. Preemptive lamivudine was given throughout the chemotherapy course. HBsAg, HBV envelope antigen (HBeAg), anti-HBV envelope antibody (HBe Ab), serial serum alanine transaminase (ALT), quantitative HBV viral DNA analysis, and HBV DNA precore promoter and precore sequence were monitored. One patient carried wild type and the other five precore mutant strain of HBV by examination of HBV sequence in precore promoter and precore region. No evident HBV reactivation developed, and all patients tolerated lamivudine well. During the 6-to-8-month follow-up after cessation of cytotoxic therapy and withdrawal of lamivudine, serum ALT remained unchanged, although an increase of HBV DNA levels in four patients was found. No emergence of the tyrosine-methionine-aspartate-aspartate (YMDD) lamivudine-selective resistant strain was observed in the six patients. Preemptive use of lamivudine can effectively prevent reactivation of HBV in breast cancer patients receiving postoperative adjuvant chemotherapy. Lamivudine can be discontinued safely without emergence of lamivudine-resistant HBV strain or rebound HBV flare-up. The candidate for the use of preemptive lamivudine in HBV carriers who need short-term chemotherapy remained to be investigated.  相似文献   
503.
The absolute bioavailability of cefprozil, a new oral cephalosporin, in four beagles was evaluated. In this two-way crossover study, each dog received a 125-mg dose of cefprozil either as an oral aqueous solution or as a 15-min intravenous infusion. A high-performance liquid chromatographic assay with UV detection was employed for the determination of cefprozil concentrations in plasma and urine. Key pharmacokinetic parameters were calculated by noncompartmental methods. Cefprozil was well absorbed after oral administration, and peak concentrations of 17.6 to 26.6 micrograms/ml were attained at 60 min after drug administration. The apparent elimination half-life of cefprozil was about 70 min. The renal clearance was about 60% of total body clearance and is suggestive of significant nonrenal clearance. The absolute bioavailability of cefprozil ranged from 67.1 to 79.1% in the dogs.  相似文献   
504.
Wu GJ  Chen WF  Sung CS  Jean YH  Shih CM  Shyu CY  Wen ZH 《Neuroscience》2007,147(2):294-303
Spinal cord ischemic injury usually results in paraplegia, which is a major cause of morbidity after thoracic aorta operations. Ample evidence indicates that massive release of excitatory amino acids (EAAs; glutamate) plays an important role in the development of neuronal ischemic injuries. However, there is a lack of direct evidence to indicate the involvement of EAAs in the glutamate metabolizing system (including the glutamate transporter isoforms, i.e. the Glu-Asp transporter (GLAST), Glu transporter-1 (GLT-1), and excitatory amino acid carrier one (EAAC1); glutamine synthetase (GS); and glutamate dehydrogenase (GDH)) in spinal cord ischemia. In the present results, we found that methylprednisolone (MP; intrathecal (i.t.) injection, 200 mug twice daily administered for 3 days before ischemia), a synthetic glucocorticoid, is the therapeutic agent for the treatment of spinal injuries in humans, can significantly reduce the ischemia-induced motor function defect and down-regulate the glutamate metabolizing system (including GLAST, GLT-1, GS, and GDH) in male Wistar rats. The spinal cord ischemia-induced down-regulation of EAAC1 protein expression in the ventral portion of the lumbar spinal cord was partly inhibited by pretreatment with i.t. MP. However, MP did not affect the down-regulation of EAAC1 in the dorsal portion of the lumbar spinal cord after spinal cord ischemia. The i.t. injection of MP alone did not change the neurological functions and the expression of proteins of the glutamate metabolizing system in the spinal cord. Our results indicate that spinal cord ischemia-induced neurological deficits accompany the decrease in the expression of proteins of the glutamate metabolizing system in the lumbar portion of the spinal cord. The i.t. MP pretreatment significantly prevented these symptoms. These results support the observation that MP delivery through an i.t. injection, is beneficial for the treatment of spinal cord ischemic injuries.  相似文献   
505.
OBJECTIVES: We sought to evaluate the efficacy of the antioxidant acetylcysteine in limiting the nephrotoxicity after coronary procedures. BACKGROUND: The increasingly frequent use of contrast-enhanced imaging for diagnosis or intervention in patients with coronary artery disease has generated concern about the avoidance of contrast-induced nephrotoxicity (CIN). Reactive oxygen species have been shown to cause CIN. METHODS: We prospectively studied 121 patients with chronic renal insufficiency (mean [+/-SD] serum creatinine concentration 2.8 +/- 0.8 mg/dl) who underwent a coronary procedure. Patients were randomly assigned to receive either acetylcysteine (400 mg orally twice daily) and 0.45% saline intravenously, before and after injection of the contrast agent, or placebo and 0.45% saline. Serum creatinine and blood urea nitrogen were measured before, 48 h and 7 days after the coronary procedure. RESULTS: Seventeen (14%) of the 121 patients had an increase in their serum creatinine concentration of at least 0.5 mg/dl at 48 h after administration of the contrast agent: 2 (3.3%) of the 60 patients in the acetylcysteine group and 15 (24.6%) of the 61 patients in the control group (p < 0.001). In the acetylcysteine group, the mean serum creatinine concentration decreased significantly from 2.8 +/- 0.8 to 2.5 +/- 1.0 mg/dl (p < 0.01) at 48 h after injection of the contrast medium, whereas in the control group, the mean serum creatinine concentration increased significantly from 2.8 +/- 0.8 to 3.1 +/- 1.0 mg/dl (p < 0.01). CONCLUSIONS: Prophylactic oral administration of the antioxidant acetylcysteine, along with hydration, reduces the acute renal damage induced by a contrast agent in patients with chronic renal insufficiency undergoing a coronary procedure.  相似文献   
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Abstract: Cases of isolated tuberculous liver abscess are rare. The diagnosis is often delayed or missed because of nonspecific symptoms and the disease's rare occurrence. Less than 25 cases have been documented in the imaging literature to date. This report demonstrates the difficulty in correctly diagnosing local hepatic tuberculosis. We report the case of a 56‐year‐old male with hepatitis C‐related liver cirrhosis and end‐stage renal disease treated with hemodialysis, who developed intermittent fever and hepatomegaly with unusual multiple hyperechoic hepatic lesions on ultrasound. To our knowledge, this is only the second reported case of hyperechoic mass‐like hepatic lesions on ultrasound and the only case without pulmonary involvement. A greater awareness of this rare clinical entity may prevent needless surgical interventions, because the prognosis of hepatic tuberculous abscess is good for the majority of patients if diagnosed early and prompt, effective treatment is administered.  相似文献   
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