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131.
Probucol is a lipid-lowering agent with an antioxidant effect; however, its influence on the liver remains unclear. The effects of probucol on hyperlipidemic rabbit liver are investigated to add a structural data on its therapeutical profile. Local albino rabbits were divided into three groups. 1) Hyperlipidemic group: fed with 1% cholesterol (150 g/kg/day) enriched chow for 2 months. 2) Probucol treated group: group 1 + intraperitoneal probucol (10 mg/kg/day) administration for 15 days. 3) Control group fed with normal chow. The blood lipid profile was investigated biochemically. Liver samples were examined electronmicroscopically. Within the parenchymal cells of group 1, the amount of rough surfaced endoplasmic reticulum was increased, its cisterna was dilated displaying a moderately electron dense substance in it and showed close apposition with the condensed mitochondria. In group 2, smooth surfaced endoplasmic reticulum was in extensive amounts filling almost all of the cytoplasm, displayed a reticular, degenerated appearance and was in close relation with the condensed, degenerated mitochondria. Probucol may cause degenerative changes on the liver parenchyme at the subcellular level. It alters the structure of these cells mainly acting on the smooth surfaced endoplasmic reticulum and the mitochondria that are known to be involved in cellular detoxification.  相似文献   
132.
The aim of this study was to investigate the relationship between MUC1 and MUC2 mucin expressions and clinicopathologic variables in gastric carcinomas with regard to survival times. MUC1 and MUC2 expressions were revealed immunohistochemically in 143 gastric carcinomas. Of these 143 patients, follow-up data were available for 45 (median survival time of 30 months, ranging from 2 to 80 months). MUC1 was detected in 82 (58%), and MUC2 in 60 (42%) out of 143 cases. Papillary adenocarcinomas showed significantly higher MUC1 and MUC2 immunoreactivity than did signet-ring cell and mucinous tumors (p = 0.045 and p = 0.01, respectively). MUC1 was highly positive in intestinal-type carcinomas (p = 0.006), whereas intestinal and diffuse carcinomas did not differ in MUC2 expression. There was a positive correlation between tumor differentiation and MUC1 expression. However, no correlation was found between MUC1 and MUC2 expressions and angiolymphatic invasion. According to the TNM classification, stage 1A tumors have significantly lower rates of MUC1 reactivity compared to higher stages (p = 0.04). The patients with gastric carcinomas expressing MUC1 showed significantly poorer survival than those without MUC1 expression (p = 0.04). The present study suggests that MUC1 expression be a useful prognostic factor for predicting the outcome of gastric carcinoma patients, whereas the role of MUC2 expression is still unclear.  相似文献   
133.
Sympathetic skin response in diabetic neuropathy   总被引:21,自引:0,他引:21  
Autonomic neuropathy is a complication of diabetes mellitus (DM) in substantial proportion of cases and may cause definite autonomic symptoms. Because conventional electrophysiological methods do not assess the autonomic nervous system, simple reproducible tests were developed. One of them is sympathetic skin response (SSR) which provides useful information about the status of sympathetic postganglionic function. The aim of this study is to perform SSR in diabetic patients to see whether this test can be used as an electrophysiological method for the diagnosis and confirmation of diabetic autonomic neuropathy. 20 diabetic patients who had electrophysiologically confirmed polyneuropathy but showed no symptoms or signs referable to autonomic system dysfunction were included. 14 (70%) patients demonstrated abnormal SSR. 2 abnormal patterns were observed. An absent response in at least one tested lower extremity (50%) and prolonged foot with normal hand latency (20%). 6 patients (30%) demonstrated no abnormalities. Foot and hand latencies in diabetics did not differ significantly from those of normal controls (p: 0.4, p: 0.1) and no correlation could be found with latencies and duration of sickness, patient's age and HbA1c values. We believe latency measurement is an objective measure of conduction in multineural pathways and can detect subclinical involvement of sympathetic nervous system in diabetics who do not manifest symptoms or signs referable to autonomic system dysfunction.  相似文献   
134.
Aim: In this population‐based study, we aimed to determine the total sleep duration (TSD), its association with socio‐economic status (SES) and behavioural symptoms among schoolchildren. Methods: A cross‐sectional study was performed among schoolchildren in Istanbul. A structured questionnaire evaluating the sleep schedule variables was filled out by their parents. SES was determined according to the Turkish SES scale. Results:  The mean age of 2669 children was 8.2 ± 2.4 years, and 51% of the students were girls. The mean TSD was 10.20 ± 1.04, and the mean bedtime was 21.57 ± 0.56 (both in hours, minutes ± SD). Boys tended to go bed later (p = 0.004) and slept less than girls (p = 0.02). The duration of sleep disruptions increased (p < 0.001), whereas TSD decreased with age (p < 0.001). Multiple linear regression revealed that waking time and TSD decreased significantly (p < 0.05) with higher SES among both girls and boys. Sleep fragmentation was associated with habitual snoring, parasomnias, daytime sleepiness and conduct symptoms. Conclusion: Decreased total sleep duration is more prominent in boys, older children and children among higher socio‐economic status. Insufficient sleep attributed to shortened total sleep duration by age and higher socio‐economic status might have a negative effect on both sleep hygiene and psychological well‐being in schoolchildren.  相似文献   
135.

Objective

In this study, we aim to demonstrate that measurement of the malondialdehyde (MDA) level in the umbilical cord blood of newborn infants born via cesarean section (C/S) and normal vaginal delivery (NVD) is indicative of oxidative stress during the perinatal period.

Methods

The study was conducted at Bakirkoy Training and Research Hospital between January 2006 and April 2006 on 15 newborns born via elective C/S, 15 newborns born via emergency C/S, and 15 newborns born via normal vaginal delivery. Complete blood count, total bilirubin, glucose, creatinine phosphokinase (CPK), uric acid, iron, blood gas, and malondialdehyde levels were measured in the umbilical cord blood

Findings

Malondialdehyde levels in the umbilical cord blood in the emergency C/S and NVD groups were found to be statistically and significantly higher than those in the elective C/S group. In the emergency C/S group, it was determined that the malondialdehyde level increased as the oxygen saturation of the umbilical cord blood increased. In the NVD group, a positive correlation was detected between the total bilirubin and malondialdehyde levels in the umbilical cord blood. In the emergency C/S group, the malondialdehyde level was recorded to be high in the infants with high level of uric acid in the umbilical cord blood.

Conclusion

We concluded that the malondialdehyde level in umbilical cord blood could serve as an indication of perinatal oxidative stress and that it could thus help in preventing permanent damage.  相似文献   
136.
Mitral regurgitation due to papillary muscle rupture after blunt chest trauma is uncommon. Sudden onset severe mitral regurgitation may lead to death due to heart failure if surgical repair is delayed. A previously healthy 12-year-old girl underwent splenectomy and chest tube insertion for pneumothorax after a traffic accident in a vehicle 15 days before. She was discharged from the hospital after a nine-day follow-up. She was presented to our hospital due to respiratory distress. On physical examination, an apical holosystolic murmur radiating to the axillary region was recognized. Transthoracic echocardiogram showed severe mitral regurgitation with freely moving posterior mitral chordae and prolapse of the posterior mitral valve leaflet. She received reimplantation of the complete ruptured posteromedial papillary muscle of the mitral valve. Her medical condition improved after the operation. On the postoperative echocardiogram, the left ventricular systolic function was normal with no mitral regurgitation.  相似文献   
137.
Gonadotropin-releasing hormone analog (GnRHa) therapy is used in idiopathic central precocious puberty (ICPP) worldwide. It has also been shown that during this therapy, body mass index (BMI) increases slightly as a side effect. We investigated the side effects of GnRHa treatment in ICPP on body composition and insulin resistance (IR). Twenty girls (7.55 +/- 1.02 y) with ICPP were treated with GnRHa (leuprolide) for an average of 20.83 +/- 4.8 months. Bioelectrical Impedance Analysis (BIA) was used to measure the body's fat balance. Nine patients out of 20 (45%) had significant gain weight. We showed a significant elevation in trunk fat mass compare to baseline values (p < 0.01). These nine patients had high homeostasis model assessment (HOMA)-IR and low glucose/insulin (G/I) index. This study showed a slight increase in BMI, moderate increase in total body fat, and exaggerated elevation in trunk fat mass and IR in GnRHa-treated ICPP children.  相似文献   
138.
Diffuse peritoneal malignant mesothelioma is a rare, progressive, and ultimately fatal disease and it can present as primary peritoneal carcinoma or ovarian cancer. Differential diagnosis is important to establish appropriate management. In this article the clinical presentation, immunuhistochemical and histopathological features of 8 diffuse peritoneal malignant mesothelioma cases presented as peritoneal carcinoma or ovarian cancer are evaluated. According to findings of all reported cases, we concluded that clinical distinction of malignant mesothelioma from ovarian cancer or peritoneal adenocarcinoma is very difficult. Differential diagnosis is reliably achieved by immune profile of the tumors with a systematic approach of both positive and negative mesothelioma markers.  相似文献   
139.

OBJECTIVE:

To investigate the role of oxidant/antioxidant status and protein oxidation in the development of age-related macular degeneration.

METHOD:

The activities of serum superoxide dismutase and glutathione peroxidase and the levels of serum malondialdehyde, advanced oxidation protein products, glutathione and vitamin C were measured in 25 patients with age-related macular degeneration and 25 control subjects without age-related macular degeneration.

RESULT:

The malondialdehyde and advanced oxidation protein product levels in the serum were significantly higher in the age-related macular degeneration patient group than in the control group (p<0.05). The superoxide dismutase activity in the serum was significantly lower in the age-related macular degeneration patient group than in the control group (p<0.05). The levels of vitamin C and glutathione and the activity of glutathione peroxidase in the serum were unchanged between groups (p>0.05).

CONCLUSION:

The results of the present study suggest that decreased effectiveness of the antioxidant defense system and increased oxidative stress may play a role in the pathogenesis of age-related macular degeneration.  相似文献   
140.
Serum concentrations of low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TGs) and total cholesterol (TC) are important heritable risk factors for cardiovascular disease. Although genome-wide association studies (GWASs) of circulating lipid levels have identified numerous loci, a substantial portion of the heritability of these traits remains unexplained. Evidence of unexplained genetic variance can be detected by combining multiple independent markers into additive genetic risk scores. Such polygenic scores, constructed using results from the ENGAGE Consortium GWAS on serum lipids, were applied to predict lipid levels in an independent population-based study, the Rotterdam Study-II (RS-II). We additionally tested for evidence of a shared genetic basis for different lipid phenotypes. Finally, the polygenic score approach was used to identify an alternative genome-wide significance threshold before pathway analysis and those results were compared with those based on the classical genome-wide significance threshold. Our study provides evidence suggesting that many loci influencing circulating lipid levels remain undiscovered. Cross-prediction models suggested a small overlap between the polygenic backgrounds involved in determining LDL-C, HDL-C and TG levels. Pathway analysis utilizing the best polygenic score for TC uncovered extra information compared with using only genome-wide significant loci. These results suggest that the genetic architecture of circulating lipids involves a number of undiscovered variants with very small effects, and that increasing GWAS sample sizes will enable the identification of novel variants that regulate lipid levels.  相似文献   
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