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41.
Metabolic Brain Disease - Loss of dopaminergic neurons following Parkinson’s disease (PD) diminishes quality of life in patients. The present study was carried out to investigate the...  相似文献   
42.
Over the last years, electronic cigarettes (ECs) have become more popular, particularly in individuals who want to give up smoking tobacco. The aim of the present study was to assess the influence of the different e-smoking liquids on the viability and proliferation of human periodontal ligament fibroblasts. For this study six test solutions with components from ECs were selected: lime-, hazelnut- and menthol-flavored liquids, nicotine, propylene glycol, and PBS as control group. The fibroblasts were incubated up to 96 h with the different liquids, and cell viability was measured by using the PrestoBlue® reagent, the ATP detection and the migration assay. Fluorescence staining was carried out to visualize cell growth and morphology. Data were statistically analyzed by two-tailed one-way ANOVA. The cell viability assay showed that the proliferation rates of the cells incubated with nicotine or the various flavored liquids of the e-cigarettes were reduced in comparison to the controls, though not all reductions were statistically significant. After an incubation of 96 h with the menthol-flavored liquid the fibroblasts were statistically significant reduced (p?相似文献   
43.
This study evaluated the effects of N-acetylcysteine as a scavenger of radical oxygen species on myocardial injury as a remote organ after skeletal muscle ischaemia–reperfusion. Twenty male Wistar rats were allocated randomly into two experimental groups: ischaemia–reperfusion and ischaemia–reperfusion?+?N-acetylcysteine. All animals underwent 2 h of ischaemia by occlusion of the femoral artery followed by 24 h of reperfusion. Rats treated with N-acetylcysteine were given an intravenous dose of 150 mg/kg, immediately before reperfusion. After the reperfusion period, animals were euthanized and hearts harvested for histopathological analysis under light microscopy. In the ischaemia–reperfusion group, tissues showed histological changes with interstitial oedema, neutrophil infiltration and adhesion of neutrophils to the endothelium, haemorrhage and coagulative necrosis. Histopathologically, there was a significant difference (P?N-acetylcysteine significantly decreased myocardial injury induced by skeletal muscle ischaemia–reperfusion according to our histological findings.  相似文献   
44.
The aim of this study was to determine the seroprevalence of Neospora caninum infection in dogs and cattle from Hamedan province (West of Iran). Blood samples were collected from 1,046 cattle and 270 dogs in this area. Cattle and dog samples were tested and analyzed using ELISA and IFAT, respectively. IgG-antibodies to N. caninum were found in 27 and 17.4 % of dogs and cattle samples, respectively. In cattle study, The association between infection and type of cattle was statistically significant (P?=?0.004). Also, significant statistical differences were observed regarding to stray canids presence in farm (P?P?P?=?0.195) and breed (P?=?0.077). In dog study, there was statistical differences among age groups (P?P?P?=?0.112). This study is the first report of N. caninum infection in dogs and cattle from west of Iran. There is both horizontal and vertical transmission of N. caninum in this area, and the presence of stray dogs may be a risk factor for N. caninum infection in cattle. N. caninum is an important factor in the economic losses of the cattle breeding in Hamedan province. Therefore, further investigations and designing control strategies for improving management in cattle farms is highly recommended.  相似文献   
45.
The pressure to use sustainable materials and adopt practices reducing the carbon footprint of the construction industry has risen. Such materials include recycled concrete aggregates (RCA) made from waste concrete. However, concrete made with RCA often presents poor fresh and hardened properties along with a decrease in its durability performance, especially when using its fine fraction (i.e., FRCA). Most studies involving FRCA use direct replacement methods (DRM) to proportion concrete although other techniques are available such as the Equivalent Volume (EV) and Particle Packing Models (PPMs); yet their impact on the durability performance, especially its performance against freezing and thawing (F/T), remains unknown. This work, therefore, appraises the F/T resistance of FRCA mixtures proportioned through various mix proportioning techniques (i.e., DRM, EV and PPMs), produced with distinct crushing processes (i.e., crusher’s fines vs. finely ground). The results show that the mix design technique has a significant influence on the FRCA mixture’s F/T resistance where PPM-proportioned mixtures demonstrate the best overall performance, exceeding the specified requirements while DRM-proportioned mixtures failed F/T resistance requirements. Moreover, the crushing process plays an important role in the recycled mixtures’ cracking behavior under F/T cycles, where less processing leads to fewer cracks while remaining the most sustainable option overall.  相似文献   
46.
Shallow lingual vestibule and lack of keratinized attached mucosa are considered risk factors for the long‐term success of dental implants. This article describes a modified surgical approach accompanied by a free gingival graft to correct the shallow lingual/buccal vestibule and to increase the keratinized tissue around dental implants.  相似文献   
47.
The present study investigated the effects of aerial parts of Phlomis anisodonta methanolic extract (PAE) on streptozotocin (STZ)-induced diabetic rats by measuring fasting blood glucose, serum insulin, change in body weight, ferric reducing antioxidant power (FRAP), lipid peroxidation (LPO), and liver antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). Male Wistar rats were randomly divided into six groups of six animals. Treatment of diabetic rats with oral administration of PAE at doses of 100, 200 and 400 mg kg(-1) for 10 days resulted in a significant reduction in fasting blood glucose, and an increase in serum insulin levels in comparison with diabetic control group. PAE also protected rats from STZ-induced loss in body weight. Hepatic FRAP increased and LPO in diabetic rats decreased after treatment by PAE at doses of 200 and 400 mg kg(-1). PAE-treated diabetic rats at three doses indicated a significant increase in hepatic SOD, CAT, and GPx activities. These results suggest that PAE is beneficial in the control of diabetes by reduction of blood glucose and increasing insulin levels and combating oxidative stress by activation of hepatic antioxidant enzymes.  相似文献   
48.
BACKGROUND AND OBJECTIVES: We aimed to treat different pathologic types of basal cell carcinomas (BCCs) using photodynamic therapy (PDT). STUDY DESIGN/MATERIALS AND METHODS: Thirty lesions in six patients underwent PDT. The photosensitizer used was Photoheme, a hematoporphyrin derivative IX. It was injected intravenously at the dose of 2-3.25 mg/kg. After 24 hours, the lesions were illuminated by laser light (lambda = 632 nm, light exposure dose = 100-200 J/cm2). Lesions were evaluated pre and post-operatively and at follow-up sessions (of up to 6 months). RESULTS: After a single session of PDT, the average response rate in different histopathologic kinds of basal cell carcinoma (e.g., ulcerative, superficial, nodular, and pigmented forms) were 100%, 62%, 90%, and 14%, respectively. In patients who responded completely, the cosmetic results were excellent and there were no recurrence at 6th month of follow-up. CONCLUSION: Although PDT seems to be an effective treatment modality for superficial, ulcerative, and nodular BCCs, it is not recommended for pigmented lesions.  相似文献   
49.
Six labdanes (1-6) and four isopimaranes (7-10), including three new natural products (7, 9, and 10), were isolated from Platycladus orientalis, and their structures determined using 1D and 2D NMR methods, ion-cyclotron resonance HRMS, and optical rotation data. Relative configurations of all chiral centers in the isopimaranes were determined using NOESY experiments at 600 and 800 MHz. Specific optical rotation data were used to correlate absolute configurations. Compounds 1-9 and aframodial (11) were tested for their in vitro antiplasmodial activity and for their ability to induce changes of erythrocyte shape in order to obtain data about possible correlation between the two effects. All compounds tested exhibited weak (IC(50) > 25 microM) in vitro antiplasmodial effects against Plasmodium falciparum strain 3D7. At the same time, the compounds caused echinocytic or stomatocytic changes of the erythrocyte membrane curvature, indicative of their incorporation into the lipid bilayer, in the concentration region where the antiplasmodial activity was observed. The antiplasmodial effect of these compounds thus appears to be an indirect effect on the erythrocyte host cell. Weak or moderate antiplasmodial activity observed with many other apolar natural products, in particular those with amphiphilic structures, is also likely to be an indirect effect.  相似文献   
50.
Portulaca oleracea is commonly used in Iranian folk medicine. The aqueous and ethanolic extracts were studied in mice for their ability to inhibit gastric lesions induced by HCl or absolute ethanol. In addition, their effects on gastric acid secretion were measured. Both extracts showed a dose-dependent reduction in severity of ulcers. The highest dose of extracts exerted similar activity to sucralfate. The oral and intraperitoneal administration of extracts reduced the gastric acidity in pylorus-ligated mice. These results suggest that Portulaca oleracea has gastroprotective action and validates its use in folk medicine for gastrointestinal diseases.  相似文献   
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