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41.
42.
BACKGROUND: Intra-abdominal hypertension leads to visceral organ hypoperfusion, and subsequent decompression may cause ischemia-reperfusion, releasing toxic metabolites. This study focuses on the effect of intra-abdominal hypertension on hepatic antioxidant store and the susceptibility of hepatocytes to oxidant injury. METHODS: Sprague-Dawley rats (150-180 g) were acclimatized to an environment for 3 days and then divided into two groups according to challenge based on intra-abdominal pressure (0 and 30 cm H2O for control and experimental groups, respectively). After a 90-minute challenge, the rats underwent immediate laparotomy for decompression; after a further 30 minutes, one fragment of liver from the lingual lobe (>0.1 g) was excised to measure glutathione (GSH) in vivo before portal vein perfusion. After hepatocyte isolation (viability rate > 85%), the cell density was set at 1 x 10/mL for each well. The samples were cultured in an incubator for 12 hours, after which varying concentrations of t-butyl hydroperoxide (TBHP) (0.0, 0.5, 1.0, and 2.0 mmol/L) were added into the wells. After another 5-hour incubation, the total store of intracellular GSH in vitro (GSHVT) and the hepatocyte survival rates were measured for different groups of TBHP challenge using GSH assay and MTT kits. RESULTS: The control and experimental groups consisted of 10 and 8 rats, respectively, that successfully completed the entire experimental procedure. Compared with the control group, the in vivo GSH store was significantly reduced after the intra-abdominal pressure challenge (mean +/- SE, 968.1 +/- 63.5 vs. 1,581.0 +/- 115.3 nmol/g of protein; p = 0.001). After the hepatocyte isolation, the GSHVT stores at various TBHP concentrations in the experimental rats were also similarly and significantly decreased relative to the control animals (894.4 +/- 56.4, 804.2 +/- 118.4, 586.9 +/- 86.6, and 410.2 +/- 87.4 nmol/g of protein vs. 1,282.2 +/- 112.0, 1,156.6 +/- 91.0, 995.2 +/- 92.7, and 866.8 +/- 62.4 nmol/g of protein for TBHPs of 0.0, 0.5, 1.0, and 2.0 mmol/L, respectively; all p < 0.05). Moreover, from photocytometry, the hepatocyte survival rates were significantly reduced for the experimental rats compared with the control animals after challenge with various TBHP concentrations (survival was 100%, 91.1%, 81.3%, and 72.8% vs. 100%, 99.2%, 95.0%, and 88.2%, respectively, for TBHPs of 0.0, 0.5, 1.0, and 2.0 mmol/L; p < 0.05 for the last two). CONCLUSION: This animal study demonstrated that intra-abdominal hypertension and subsequent decompression deplete the total in vivo GSH store in rat livers, probably via the mechanism of ischemia-reperfusion injury, and the GSHVT after hepatocyte isolation, which makes the isolated hepatocytes of rats more susceptible to oxidant challenge.  相似文献   
43.
OBJECTIVES: The prognostic impact of diabetes mellitus and its association with virological factors on patients with hepatocellular carcinoma (HCC) are unclear. This study aimed to investigate the outcome in HCC patients undergoing resection with and without diabetes mellitus and the interaction with hepatitis B virus (HBV) and hepatitis C virus (HCV). METHODS: A total of 239 HCC patients were included. Survival and tumour recurrence were analysed according to the status of diabetes mellitus and viral hepatitis. RESULTS: Diabetic patients tended to have an overall decreased survival compared with non-diabetic patients in 32 +/- 19 months of follow-up. A total of 113 (47%) patients developed tumour recurrence during the follow-up period. No significant difference of tumour recurrence between diabetic and non-diabetic patients, or between patients seropositive and seronegative for HBV surface antigen (HBsAg), was noted. Stratified analysis showed that diabetic patients with HBV but not with HCV infection had a poor long-term outcome. In the HBV group, the one-, three- and five-year survival rates were 83%, 51% and 41% versus 90%, 78% and 73% in diabetic and non-diabetic patients, respectively, compared with 90%, 83% and 42% versus 91%, 73% and 73% in the HCV group with and without diabetes mellitus, respectively. Cox multivariate analysis disclosed that diabetic patients seropositive for HBsAg had a significantly poor survival. CONCLUSIONS: Diabetes mellitus does not affect the long-term survival in HCV-related HCC but is a recurrence-independent poor prognostic factor for HBV-related HCC.  相似文献   
44.
PURPOSE: To analyze results of percutaneous catheter drainage of large fluid collections in the head and neck region noted in the immediate postoperative period. MATERIALS AND METHODS: Thirty-four consecutive patients with 41 large fluid collections in the head and neck detected 7-10 days after oncologic surgery underwent percutaneous catheter drainage. There were 29 men and five women, with a mean age of 52.2 years (95% CI: 47.8-56.7). Each patient had a surgical drain placed in the posterior neck triangle; three patients had low-grade fever and six had diabetes at the time of percutaneous catheter drainage. Conventional management consisting of serial needle aspirations at bedside followed by pressure dressing failed in 15 of 34 patients (44%). Ultrasound-guided drainage was performed and catheters were connected to vacuum balls for continuous suction drainage. RESULTS: The average fluid volume estimated by sonographic measurement was 84 cm(3) (95% CI: 57-112 cm(3)). The fluid content was serosanguinous in 46% (19 of 41), uncoagulated blood in 32% (13 of 41), pus in 15% (six of 41), and saliva in 7% (three of 41). The mean duration of catheter drainage was nine days (95% CI: 7-10 d) and mean fluid drainage was 287 mL (95% CI: 188-387 mL). Ninety-one percent of patients (31 of 34) were successfully treated with initial catheter drainage. Three patients had recurrent fluid collections at the same locations: two were treated with repeated catheter insertions and one required a limited open drainage. No complication related to catheter drainage was noted at 6-month follow-up. CONCLUSION: Percutaneous catheter drainage is effective for large fluid collections in the head and neck region noted in the immediate postoperative period irrespective of contents.  相似文献   
45.
The purpose of the study is to test the effectiveness of acupressure on sleep quality of end-stage renal disease patients. The study was a randomized controlled trial; qualified patients in the dialysis centers of four major hospitals were randomly assigned into an acupressure group, a sham acupressure group, and a control group. A total of 98 participants were included in the study. The main outcomes measured were the Pittsburgh sleep quality index (PSQI) and the sleep log. Data were collected at pretreatment and following treatment. Primary statistical analysis was by means of Analysis of Covariance, the Kruskal-Wallis Test and repeated measure ANOVA. The results indicated that PSQI scores of the acupressure group have a significantly greater improvement (p < 0.01) than the control group. However, there were no differences between the acupressure group and the sham group or the sham group and the control group (p > 0.05). Subscales of PSQI were further analyzed. Results demonstrated significant differences between the acupressure group and the control group in subjective sleep quality (p = 0.009), sleep duration (p = 0.004), habitual sleep efficiency (p = 0.001), and sleep sufficiency (p = 0.004). Significant differences in the subscale of subjective sleep quality (p = 0.003) between the sham acupressure group and the control group were also observed. Sleep log data showed that the acupressure group significantly decreased awake time and improved quality of sleep over time more than the control group (p < 0.01). The improvement could be seen as soon as the acupoints massage was implemented, and it was maintained through the post intervention.  相似文献   
46.
BACKGROUND: The delivery of circulating tryptophan to the brain and its conversion to serotonin vary directly with plasma concentrations of tryptophan and inversely with those of other large neutral amino acids (LNAAs). Although carbohydrate-rich, protein-free formula diets have been shown to elevate, and high-protein diets to depress, the tryptophan-LNAA ratio, few data are available about this ratio's responses to actual meals. OBJECTIVE: We determined whether carbohydrate-rich or protein-rich breakfasts, such as those Americans normally eat, produce substantial differences in the plasma tryptophan-LNAA ratio and in the corresponding ratio for tyrosine, the precursor of brain dopamine and norepinephrine. DESIGN: Nine overnight-fasted subjects consumed, 3-7 d apart, a carbohydrate-rich (69.9 g carbohydrate and 5.2 g protein) and a protein-rich (15.4 g carbohydrate and 46.8 g protein) breakfast. Blood samples collected at baseline and after 40, 80, 120, and 240 min were assayed for tryptophan, tyrosine, the 5 other LNAAs, and insulin. RESULTS: The carbohydrate-rich and protein-rich breakfasts had significantly different effects on both the plasma tryptophan-LNAA and tyrosine-LNAA ratios (each P < 0.01). Among the 8 subjects who consumed both breakfasts, the median difference for tryptophan:LNAA was 54% (range: 36-88%) and for tyrosine:LNAA was 28% (range: 10-64%). Insulin concentrations rose significantly after the carbohydrate but not after the protein meal. CONCLUSIONS: High-carbohydrate and high-protein breakfasts similar to those Americans normally eat can cause substantial differences in the plasma tryptophan ratio and thus, probably, in brain tryptophan concentrations and serotonin synthesis. Such meals also change the plasma tyrosine ratio and may thereby modify catecholamine synthesis.  相似文献   
47.
Salvia miltiorrhiza Bunge, known as Danshen in Chinese traditional medicine is effective at promoting blood circulation and removing (or decreasing) blood stasis. In the present study, we selected aging, 24-month-old guinea pigs as the animal experimental models and fed them a diet containing 75, 100 or 150 mg/(kg day) of water-soluble extract components of Salvia miltiorrhiza Bunge (WSm) for 28 days, respectively, in order to evaluate the effects of WSm on their abnormal hemorheological parameters.  相似文献   
48.
亮氨酸脑啡肽的电子结构及构效关系研究   总被引:1,自引:0,他引:1  
对亮氨酸脑啡肽进行了量子化学(INDO)计算,研究其电子结构特征,讨论其活性部位、作用机理及构效关系。同吗啡和R31833进行了活性部位的电子结构与空间结构比较,推断它们的活性药效结构具有共同特点,与阿片受体相互作用时作用方式相同,作用部位有对应关系,因而具有相同的药理性质。  相似文献   
49.

Introduction  

Procalcitonin (PCT) has been proposed as a marker of infection in critically ill patients; its level is related to the severity of infection. We evaluated the value of PCT as a marker of bacterial infection for emergency department patients.  相似文献   
50.
Summary DNA enriched for supercoiled plasmids prepared from the 3 m plasmid-enriched, [ +], [2 m°] strain 6-1G-P188 and from the [2 m+] [+] strain LL20 can be used to transform a recipient strain to +. Fractionation of the former preparation by electrophoresis showed that the 3 Mm plasmid band contained the transforming activity.  相似文献   
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