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81.
Pancreatic transplant imaging   总被引:1,自引:0,他引:1  
Forty-four clinical episodes of suspected (pancreas) transplant rejection in 17 pancreatic transplantation patients were reviewed retrospectively. The clinical impression of acute graft rejection, chronic rejection, or nonrejection in each episode was correlated with the results of 19 nuclear medicine, 12 ultrasound (US), and 44 magnetic resonance (MR) imaging studies. US was found to be a moderately sensitive (82%) method of detecting graft rejection. US also was effective in identifying intra- and peripancreatic fluid accumulations. Nuclear medicine imaging was also a sensitive technique (86%) and the only modality that provided physiologic information regarding graft perfusion. MR imaging allowed correct prediction of the presence or absence of graft rejection in 39 of 44 cases (sensitivity, 100%; specificity, 76%) and was an effective means of detecting pathologic fluid collections. Nuclear medicine, US, and MR imaging are all believed to be sensitive methods of detecting graft rejection and are complementary adjuncts to the clinical evaluation of pancreatic transplants.  相似文献   
82.
辽吉冰凉花总甙对心功能影响的实验研究   总被引:3,自引:0,他引:3  
迟立国  陈正  陈羽 《药学学报》1988,23(2):91-95
辽吉冰凉花总甙(APAW)1.0mg/kg iv,能使麻醉家兔正常心脏的P-dP/dt环体面积(LO),LV-dP/dtmax,Vpm及LVSP比药前增大,HR减慢。APAW和冰凉花(AAR)及毒毛旋花子甙K(SK)一样,能明显改善衰竭兔心的心功能。静脉恒速输入0.5 mg/ml APAW,25min后,心衰家兔的LVSP,LV—dP/dt max,LO均明显回升,LVEDP降低,t-dP/dt max缩短。三种强心甙的最大强心效力无显著性差异。但APAW的治疗宽度和治疗指数均较AAR和SK为大,而AAR和SK间则无显著性差异。  相似文献   
83.
PURPOSE OF REVIEW: In the USA, 8-10 million people are morbidly obese, which is associated with a high frequency of comorbidities. The most effective treatment is surgery. Of around 180,000 bariatric operations performed in 2005, 80% were Roux-en-Y gastric bypass, consisting of a small gastric pouch to minimize food intake and a Roux-en-Y of distal small bowel bypassing the upper gastrointestinal tract. The precise mechanisms whereby Roux-en-Y gastric bypass achieves sustained weight loss remain unknown. To gain insight into the catabolic events of sustained weight loss we developed a diet-induced obese Roux-en-Y gastric bypass rat model. We review our rat model data from the novel viewpoint of the catabolic state, comparing it with the limited human data available and the catabolic events occurring in cancer anorexia/cachexia syndrome. RECENT FINDINGS: Current data suggest the involvement of mechanisms other than restrictive and malabsorptive factors of the Roux-en-Y gastric bypass, classically thought of as the mechanisms responsible for weight loss. Based on available data, gastrointestinal hormones and cytokines play a key role in reducing food intake and regulating energy homeostasis. Because of the cross talk between peripheral modulators and the hypothalamus, a critical role for their interaction in the outcome of Roux-en-Y gastric bypass is emerging. SUMMARY: In our Roux-en-Y gastric bypass rat model many of the changes in gastrointestinal hormones, adipokines and cytokines as well as in hypothalamic neuropeptides and neurotransmitters resemble the changes observed in the anorexia/cachexia rat model, suggesting that Roux-en-Y gastric bypass triggers a catabolic state responsible for loss of appetite and prolonged body weight reduction.  相似文献   
84.
1 Bleomycin-induced lung injury is widely used as an experimental model to investigate the pathophysiology of pulmonary fibrosis but the alterations in the pharmacological responsiveness of airways isolated from bleomycin-exposed animals has been scarcely investigated. The aim of this study was to examine the in vitro tracheal responses to muscarinic receptor stimulation with carbachol in a rat bleomycin model. 2 Concentration-response curves to carbachol (10 nm to 0.1 mm) were obtained in tracheal rings isolated from Sprague-Dawley rats 14 days after endotracheal bleomycin or saline. The intracellular calcium signal in response to carbachol (10 microm) was measured by epifluorescence microscopy using fura-2 in primary cultures of tracheal smooth muscle cells from bleomycin- and saline-exposed rats. Circulating plasma tumour necrosis factor (TNF)-alpha/interleukin (IL)-1beta levels were measured by enzyme-linked immunosorbent assay. 3 Maximal contraction in response to carbachol was significantly greater in tracheal rings from bleomycin-exposed rats compared with controls (15.8 +/- 1.3 mN vs. 11.8 +/- 1.4 mN; n = 19, P < 0.05). 4 Carbachol (10 microm) elicited a transient increase of intracellular calcium with greater increment in tracheal smooth muscle cells from bleomycin-exposed rats compared with controls (372 +/- 42 nmvs. 176 +/- 20 nm; n = 7, P < 0.01). 5 Circulating plasma levels of TNF-alpha/IL-1beta were augmented in bleomycin-exposed rats compared with controls. Tissue incubation with TNF-alpha (100 ng ml(-1))/IL-1beta (10 ng ml(-1)) increased in vitro tracheal responsiveness to carbachol. 6 In conclusion, tracheal contraction in response to muscarinic receptor stimulation with carbachol was increased in bleomycin-exposed rats. This in vitro cholinergic hyperresponsiveness may be related to the augmented levels of inflammatory cytokines in bleomycin-exposed rats.  相似文献   
85.

Background

Much concern has been raised over pro-eating disorder (pro-ED) website communities, but little quantitative research has been conducted on these websites and their users.

Objective

To examine associations between levels of pro-ED website usage, disordered eating behaviors, and quality of life.

Methods

We conducted a cross-sectional, Internet-based survey of adult pro-ED website users. Main outcomes were Eating Disorder Examination Questionnaire (EDE-Q) and Eating Disorder Quality of Life (EDQOL) scores.

Results

We included responses from 1291 participants; 1254 (97.13%) participants were female. Participants had an average age of 22.0 years and a mean body mass index of 22.1 kg/m2; 24.83% (296/1192) were underweight; 20.89% (249/1192) were overweight or obese. Over 70% of participants had purged, binged, or used laxatives to control their weight; only 12.91% (163/1263) were in treatment. Mean EDE-Q scores were above the 90th percentile and mean EDQOL scores were in the severely impaired range. When compared with moderate and light usage, heavy pro-ED website usage was associated with higher EDE-Q global (4.89 vs 4.56 for medium and 4.0 for light usage, P < .001) and EDQOL total scores (1.64 vs 1.45 for medium and 1.25 for light usage, P < .001), and more extreme weight loss behaviors and harmful post-website usage activities. In a multivariate model, the level of pro-ED website usage remained a significant predictor of EDE-Q scores.

Conclusions

Pro-ED website visitors reported many disordered eating behaviors, although few had been treated. Heavy users reported poorer quality of life and more disordered eating behaviors.  相似文献   
86.
AIM: To evaluate the efficacy and the safety of azathioprine (AZA) and buthionine sulfoximine (BSO) bylocalized application into HepG2 tumor in vivo.METHODS: Different hepatoma and colon carcinoma cell lines (HepG2, HuH7, Chang liver, LoVo, RKO, SW-48, SW-480) were grown in minimal essencial medium supplemented with 10% fetal bovine serum and 1% antibiotic/antimycotic solution and maintained in a humidified 37 ℃ incubator with 5% CO2. These cells were pretreated with BSO for 24 h and then with AZA for diffe...  相似文献   
87.
BackgroundSome reports have shown that the risk of death is higher for patients admitted on weekends than for patients who go into the hospital on weekdays. This study was conducted to assess what independent influence, if any, weekend admission might have on mortality in our hospital.MethodsThe clinical data of 35,993 adult (> 14 years) patients admitted to the emergency department of Fundación Hospital Alcorcón from 1999 to 2003 were analyzed. We compared global mortality and mortality within the first 48 h according to whether the patients were admitted on the weekend or on a weekday. Elective admissions, critical care patients, children under 14 and births were not included.ResultsGlobal mortality was similar in both groups, but mortality within the first 48 h was higher for patients admitted on the weekend (OR 1.40, 95% CI 1.18–1.62, P < 0.001), even after controlling for age, gender and comorbidity (weight of diagnosis-related group and Charlson comorbidity index).ConclusionThe risk of mortality within the first 48 h is higher for patients admitted on weekends than for patients admitted on a weekday.  相似文献   
88.
Aim: The aim of this study was to determine if asthmatic children have viruses more commonly detected in lower airways during asymptomatic periods than normal children. Methods: Fifty‐five asymptomatic children attending elective surgical procedures (14 with stable asthma, 41 normal controls) underwent non‐bronchoscopic bronchoalveolar lavage. Differential cell count and PCR for 13 common viruses were performed. Results: Nineteen (35%) children were positive for at least one virus, with adenovirus being most common. No differences in the proportion of viruses detected were seen between asthmatic and normal ‘control’ children. Viruses other than adenovirus were associated with higher neutrophil counts, suggesting that they caused an inflammatory response in both asthmatics and controls (median BAL neutrophil count, 6.9% for virus detected vs. 1.5% for virus not detected, p = 0.03). Conclusions: Over one‐third of asymptomatic children have a detectable virus (most commonly adenovirus) in the lower airway; however, this was not more common in asthmatics. Viruses other than adenovirus were associated with elevated neutrophils suggesting that viral infection can be present during relatively asymptomatic periods in asthmatic children.  相似文献   
89.

BACKGROUND AND PURPOSE

Pulmonary arteries from smokers and chronic obstructive pulmonary disease patients show abnormal endothelium-dependent vascular reactivity. We studied the effect of cigarette smoke extract (CSE) on endothelin receptor B (ETB) expression in human pulmonary artery endothelial cells (HPAECs) and its role in endothelial dysfunction.

EXPERIMENTAL APPROACH

ETB receptor expression was measured by real time RT-PCR, Western blot and immunofluorescence. Cell contraction, intracellular Ca2+, F/G-actin, RhoA activity, myosin light chain phosphorylation, ET, NO, thromboxane (Tx)A2 and reactive oxygen species (ROS) were measured by traction microscopy, fluorescence microscopy, phalloidin fluorescence, colorimetric assay, Western blot, elisa and DCFDA fluorescence respectively.

KEY RESULTS

Cigarette smoke extract dose-dependently increased ETB receptor expression in HPAECs after 24 h incubation. CSE-induced ETB expression was attenuated by bosentan, the ETB receptor antagonist BQ788, the Rho kinase antagonist Y27632 and the antioxidant N-acetylcysteine. A monoclonal antibody to ET-1 prevented CSE-induced ETB receptor overexpression. Twenty-four hour exposure to ET-1 dose-dependently increased ETB receptor expression, mimicking the effect of CSE. CSE-induced ETB receptor overexpression caused greater cell contraction; increased intracellular Ca2+; increased F/G-actin and RhoA activity; increased myosin light chain phosphorylation; augmented TxA2 and ROS production; and decreased NO after acute ET-1 (10 nM). These effects were attenuated by bosentan, BQ788, Y27632 and N-acetylcysteine.

CONCLUSIONS AND IMPLICATION

Cigarette smoke extract induced ETB receptor overexpression by a feed forward mechanism mediated partly by ET release, promoting HPAEC dysfunction and attenuated by ETB receptor blockade, Rho kinase and ROS inhibition. These results provide support for the use of bosentan in CS-related endothelial dysfunction.  相似文献   
90.
Oleoylethanolamide (OEA) is an endogenous lipid mediator that decreases food intake and enhances lipid catabolism. Dietary fat stimulates OEA mobilization in the proximal small intestine, through a mechanism that requires the participation of the membrane glycoprotein CD36 (fatty acid translocase, FAT). CD36 is highly expressed in small-intestinal enterocytes and is involved in fatty acid uptake and intracellular signaling. Here, we analyze the impact of genetic CD36 deletion on OEA production in various mouse tissues under free-feeding conditions and at different times of the light/dark cycle. CD36 ablation decreases OEA levels in jejunum and plasma during the dark phase, when mice consume most of their daily food. CD36 deletion is also associated with reduced OEA levels in kidney, but not in other tissues including duodenum, stomach, adrenals, white and brown fat, heart, liver, pancreas, skeletal muscle and brain. The results underscore the important role of CD36 in jejunal OEA production linked to feeding.  相似文献   
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