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51.
AIM:To investigate the impact of cirrhosis on retinal morphology and to evaluate the role of endogenous opioids as a mediator in cirrhosis induced retinal change.METHODS:Thirty-six male rats were divided into 3 main groups; the common bile duct ligated (BDL) group, the sham-operated (Sham) group and the unoperated (Unop) group. Then each of these three main groups was divided into two subgroups; the first subgroup received daily injection of naltrexone hydrochloride (NTX) and the second group was injected with normal saline (Saline) daily. After 28d, rats were anesthetized and their right eyes were enucleated and assessed for histological changes. The thickness of the rod and cons layer, outer nuclear layer, outer plexiform layer, inner nuclear layer, inner plexiform layer and ganglion cell layer for each eye were measured in micrometers by light microscope.RESULTS:Ganglion cell layer showed significant increase in thickness in the BDL group (P<0.05). This increase was eliminated in the group where BDL rats received daily intraperitoneal injection of naltrexone hydrochloride (20 mg/kg). No other histological changes were detected in the other 5 layers we measuredCONCLUSION:The morphological change we detected in the retina of cirrhotic rats is probably due to opioids increased tone in cirrhosis since the increase in thickness in the ganglion cell layer was almost eliminated when naltrexone hydrochloride was injected. These results suggest a possible role for endogenous opioids in the morphological retinal changes detected in cirrhotic rats.  相似文献   
52.

Background

Muscle stretching is widely used in sport training and in rehabilitation. Considering the important contribution of joint position sense (JPS) to knee joint stability and function, it is legitimate to question if stretching might alter the knee JPS.

Objective

To evaluate if a stretch regimen consisting of three 30 s stretches alters the knee JPS.

Design and setting

A blinded, randomised design with a washout time of 24 h was used.

Subjects

39 healthy students (21 women, 18 men) volunteered to participate in this study.

Methods and main outcome measures

JPS was estimated by the ability to reproduce the two target positions (20° and 45° of flexion) in the dominant knee. The absolute angular error (AAE) was defined as the absolute difference between the target angle and the subject perceived angle of knee flexion. AAE values were measured before and immediately after the static stretch. Measurements were repeated three times. The static stretch comprised a 30 s stretch followed by a 30 s pause, three times for each muscle.

Results

The AAE decreased significantly after the stretching protocols for quadriceps (3.5 (1.3) vs 0.7 (2.4); p<0.001), hamstring (3.6 (2.2) vs 1.6 (3.1); p = 0.016) and adductors (3.7 (2.8) vs 1.7 (2.4); p = 0.016) in 45° of flexion, but no differences were found for values of the gastrocnemius and popliteus muscles in this angle and for the values of all muscles in 20° of flexion (p>0.05).

Conclusion

The accuracy of the knee JPS in 45° of flexion is improved subsequent to a static stretch regimen of quadriceps, hamstring and adductors in healthy subjects.  相似文献   
53.
INTRODUCTION An estimated 350 million persons worldwide are infected with hepatitis B virus (HBV). Hepatitis B carriers are at risk for development of cirrhosis and hepatocellular carcinoma. Persons with chronic hepatitis B infection need life-long monito…  相似文献   
54.
Antibiotic susceptibility testing of 70 pediatric Helicobacter pylori isolates was performed by using screening agar and disk diffusion methods. Resistance to metronidazole and tinidazole was 72 to 79% and 71 to 81% by modified disk diffusion and 77% and 78% by screening agar, respectively. Susceptibilities to amoxicillin, ampicillin, clarithromycin, tetracycline, erythromycin, and ciprofloxacin were 58, 69, 75, 68, 68, and 65%, respectively.  相似文献   
55.
Improved care of patients with small B-cell lymphomas (SBCLs) is likely to result from the ongoing discovery of molecular markers that better define these malignant neoplasms. We identified multiple gene loci whose DNA methylation patterns differed between 3 types of SBCL: B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma, mantle cell lymphoma, and grades I and II follicular lymphoma. This analysis was performed using an oligonucleotide microarray that allowed determination of the DNA methylation status of 156 loci in 38 genes. Combined bisulfite restriction analysis and methylation-specific polymerase chain reaction were used to validate the differential methylation of 6 of these genes. By using non-Hodgkin lymphoma cell lines as models, these genes were examined further for methylation and gene expression relationships. This study illustrates nonrandom epigenetic alterations in SBCLs that seem to preferentially involve lymphomas of germinal center derivation.  相似文献   
56.
This study sought to summarize clinical evidence of sour tea (Hibiscus sabdariffa L.) administration on cardiovascular disease risk factors. PubMed, Scopus, Institute for Scientific Information Web of Science, and Google Scholar were systematically searched from inception to June 2019 to identify randomized clinical trials, which assessed the effect of sour tea consumption on lipid profiles, fasting plasma glucose, and blood pressure in adult populations. Mean and standard deviation for each parameter were extracted to calculate effect size. Cochrane Collaboration tools were used to evaluate risk of bias assessment. A total of seven randomized clinical trials consisting 362 participants were included in the meta‐analysis. Pooled effect size demonstrated that sour tea consumption significantly reduces fasting plasma glucose (?3.67 mg/dl, 95% confidence interval, CI [?7.07, ?0.27]; I2 = 37%), systolic blood pressure (?4.71 mmHg, 95% CI [?7.87, ?1.55]; I2 = 53%), and diastolic blood pressure (?4.08 mmHg, 95% CI [?6.48, ?1.67]; I2 = 14%). Although no significant effect was observed on triacylglycerol, total cholesterol, and high‐density lipoprotein cholesterol following sour tea consumption, a trend toward a significant reduction was found in low‐density lipoprotein cholesterol serum concentrations (p = 0.08). This systematic review and meta‐analysis suggests that sour tea consumption could have beneficial effect in controlling glycemic status and blood pressure among adult population.  相似文献   
57.
This research was conducted to determine formaldehyde exposure of staffs in pathology laboratories, surgery rooms and endoscopy wards in eight large hospitals of Tehran University of Medical Sciences located at Tehran, Iran. Air sampling have been made by both long and short-term methods. Total numbers of samples were 160 for both methods. Nineteen samples of 160 samples were collected as blank in other non-exposed environments such as administrative sections. The mean (SD) levels of formaldehyde in long-term methods were 0.96 (0.74), 0.25 (0.21) and 0.13 (0.18) ppm, at pathology laboratories, surgery rooms and endoscopy wards, respectively. The results of measurements showed that mean (SD) concentration of formaldehyde in one hour sampling at short intervals were 0.83 (0.29), 0.23 (0.16) and 0.75 (0.25) ppm at pathology labs, surgery rooms and endoscopy wards, respectively. There were significant differences in the mean levels of formaldehyde (long-term) at surgery rooms (p < 0.02) and endoscopy wards (p < 0.005) in eight hospitals of this study. It is concluded that the concentration levels of formaldehyde at pathology laboratories exceeded recommended limit which established by the American Conference of Governmental and Industrial Hygienists ACGIH (TLV-C = 0.3 ppm). It is recommended that local exhaust ventilation should be installed to minimize the contact to formaldehyde in the staffs.  相似文献   
58.

Background  

The morbidity and mortality associated with depression are considerable and continue to increase. Depression currently ranks fourth among the major causes of disability worldwide, after lower respiratory infections, prenatal conditions, and HIV/AIDS. Crocus sativus L. is used to treat depression. Many medicinal plants textbooks refer to this indication whereas there is no evidence-based document. Our objective was to compare the efficacy of stigmas of Crocus sativus (saffron) with imipramine in the treatment of mild to moderate depression in a 6-week pilot double-blind randomized trial.  相似文献   
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