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81.
Our goal was to investigate the characteristics of the auditory brainstem reflexes in patients with hemifacial spasm (HFS) and postparalytic facial syndrome (PFS).The spasm activities and responses by supraorbital and auditory stimuli were recorded from the orbicularis oculi, the posterior auricular and the mentalis muscles in 27 HFS and 21 PFS patients. The results were compared with those of 20 controls.Blink reflex (BR) was obtained by supraorbital stimulation in normal controls and on both sides of HFS and PFS patients whereas sound evoked bilateral auditory blink reflex (ABR) in 96.3%, 90.5% and 100%, respectively. Both BR and ABR showed synkinetic spread on symptomatic sides in all patients. The posterior auricular muscle response (PAMR) was observed bilaterally in 59.3%, 42.9% and 75.0% of groups, respectively. However, there was no synkinetic spread of PAMR.Since PAMR does not show synkinetic spread even in the presence of synkinetic spread of ABR and BR, we may suggest that a distal origin may be responsible of the synkinetic spread, or PAM is probably governed by a smaller nucleus in the brainstem. Thus it may be speculated that its excitability is insufficient to stimulate the ABR nucleus, whereas the reverse process is possible.  相似文献   
82.
In this study, we aimed at the isolation and identification of indoor airborne fungal contaminants of 16 different food production facilities and warehouses located in Bursa province (Turkey). Numbers and kinds of microfungi were investigated by exposing a Petri dish of malt extract agar medium for 15 minutes and then counting the number of colonies which develop. Sampling procedure for microfungi was performed 8 times at an interval of 45 days between Dec. 1st 1995--Oct. 15th 1996. A total of 3152 colonies was counted on 864 petri plates in a one year period. As a result, 63 mould species and 4 varieties belonging to 20 genera were isolated by means of pure culture methods. Of these, 7 species and 1 variety belonging to Aspergillus and Penicillium genera are new records for Turkey.  相似文献   
83.
The future of biodiversity depends to a great extent on the conservation value of human-dominated and semi-natural habitats. In a mixed agricultural landscape in southern Costa Rica, we compared the richness and composition of terrestrial arthropod communities occurring in three habitat types along a gradient of increasing disturbance: in a large (227ha) forest fragment, small (3.8–5.3ha) forest fragments, and sun coffee (1–3ha) plantations. Pitfall trap sampling revealed decreasing morphospecies richness with increasing disturbance. Moreover, the number of species unique to a habitat type was lower in the smaller forest fragments and the coffee sites. We found significant changes in community composition associated with habitat at the levels of order (all arthropods), family (beetles), and morphospecies (carabids, scarabs, and ants). We identified no significant correlation of richness among the taxonomic orders, meaning these taxa are unable to serve as biodiversity indicators (for each other or for all arthropods) in the study region. Arthropod diversity presently found in countryside habitats is certainly lower, and perhaps less sustainable, than that of the extensive forested habitats fragmented < 40 years ago. It nonetheless remains substantial, suggesting a conservation opportunity in human-dominated landscapes of the tropics.  相似文献   
84.
The Al content of 18 patch test allergens were measured by electrothermal atomic absorption spectrophotometry. It was found that these preparations contained Al in various amounts. We conclude that the presence of Al in patch test allergens may interfere with the diagnosis and evaluations of patients to whom the test is applied.  相似文献   
85.
As a part of a large-scale work aimed at studying the health effects of boron (B) in residents of a country with the world’s largest supply, developmental effects of B are presented. Spontaneous abortions, stillbirths, and congenital malformations in addition to early infant mortality were questioned in the field by home visits. Although the number of families so far ascertained is rather small, the rates related to spontaneous abortions and stillbirths from high B exposure vs low B exposure subpopulations revealed no differences of significance, providing no evidence that B affects human development adversely.  相似文献   
86.
The present study is focused on the antimicrobial, antioxidant, cytotoxic, and DNA protective effects of methanol extract obtained from R. digitellata, R. fastigiata, R. fraxinea, and R. polymorpha species that are distributed in Turkey. The highest total phenol content was determined in R. digitellata (144.6 mgGAE/gextract), and the highest total amount of flavonoids was found in R. fastigiata (20.40 mgGAE/gextract). The content of usnic acid was determined by High-Performance Liquid Chromatography (HPLC) and the highest amount was found in R. digitellata. DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS [2,2’-azinobis(3-ethylbenzathiazoline-6-sulfonic acid)] radical scavenging methods were used for antioxidant activity. R. fraxinea showed the highest DPPH⋅ and ABTS+⋅ scavenging activity. In addition, the DNA protective effect was investigated using pBR322 plasmid DNA, and; all studied species were found to have DNA protective effects. The antibacterial activity was investigated using the disc diffusion method, and the R. digitellata methanol extract showed the best results with a 12.35 mm zone on Proteus mirabilis. On the human lung cancer (A549) and breast cancer (MDA-MB-231) cell lines, cytotoxic activity was assessed using an MTT assay. All lichen extracts were found to have a significant cytotoxic effect on both cancer cell lines at 1000 μg/mL concentration. These results suggest that Ramalina species may be potential candidates for developing new phytopharmaceuticals and functional components.  相似文献   
87.
Bee bread is a unique natural product made by bees and good for human health. It has many bioactive molecules that can treat or prevent diseases. In this study, melissopalynological methods were used to examine five bee bread samples. Major plant sources found in bee bread were Lotus spp., Trifolium spp., and Xeranthemum spp., which are from the Fabaceae and Asteraceae families. Then, the amount of phenolic compounds and major carotenoids in bee bread (BB) samples were quantified. Gallic acid, caffeic acid, quercetin, and kaempferol were found in all BB samples, with β-carotene being the most abundant carotenoid in all but BB1. In addition, the total phenolic/flavonoid content and antioxidant activities of all BB samples were determined. Total flavonoid, total phenolic, DPPH⋅, and ABTS⋅+ values were varied between 5.6–10.00 mg GAE/g DW, 1.2–4.3 mg QE/g DW, 1.2–5.5 mg TEAC/g DW, and 2.6–15.4 mg TEAC/g DW, respectively.  相似文献   
88.
Herein, new derivatives of α,β-unsaturated ketones based on oleanolic acid ( 4 a – i ) were designed, synthesized, characterized, and tested against human prostate cancer (PC3). According to the in vitro cytotoxic study, title compounds ( 4 a – i ) showed significantly lower toxicity toward healthy cells (HUVEC) in comparison with the reference drug doxorubicin. The compounds with the lowest IC50 values on PC3 cell lines were 4 b (7.785 μM), 4 c (8.869 μM), and 4 e (8.765 μM). The results of the ADME calculations showed that the drug-likeness parameters were within the defined ranges according to Lipinski's and Jorgensen's rules. For the most potent compounds 4 b , 4 c , and 4 e , a molecular docking analysis using the induced fit docking (IFD) protocol was performed against three protein targets (PARP, PI3K, and mTOR). Based on the IFD scores, compound 4 b had the highest calculated affinity for PARP1, while compound 4 c had higher affinities for mTOR and PI3K. The MM-GBSA calculations showed that the most potent compounds had high binding affinities and formed stable complexes with the protein targets. Finally, a 50 ns molecular dynamics simulation was performed to study the behavior of protein target complexes under in silico physiological conditions.  相似文献   
89.
In this study, plasma and red blood cell (RBC) antioxidant status and plasma lipid peroxidation were investigated in 46 hemodialysis patients. In addition, the effect of erythropoietin (EPO) and EPO-vitamin E combination therapy on plasma and RBC antioxidant status, and plasma lipid peroxidation were examined.

There were 10 healthy subjects in the control group and 10 hemodialysis patients in the untreated group. The third group included 36 hemodialysis patients that were given EPO (100 U/kg) for 3 months, 3 times per week. The fourth group included 36 hemodialysis-patients from the EPO group that were given EPO at a 50% decreased dose + vitamin E (300 mg/day) for 3 months.

MDA levels in the untreated group, the EPO group and the EPO + vitamin E groups were found to be higher than the control group (p<0.001, in both). Furthermore, MDA levels in both of the treatment groups were lower when compared to the untreated group (p<0.001, in both). Plasma vitamin E levels in the untreated, the EPO group and EPO + vitamin E groups were lower than the control group (p<0.001). In contrast, plasma vitamin E levels in the treatment groups were higher in comparison with the control group (p<0.05). SOD activities in the untreated, the EPO group and the EPO + vitamin E groups were found to be lower than the control group (p<0.001). SOD activities in the treatment groups were higher than the control group (p<0.001). The SOD activities in the EPO + vitamin E group increased when compared to the EPO group (p<0.001). CAT activities in the untreated, the EPO group and the EPO + vitamin E groups were found to be lower than the control group (p<0.001 in untreated and EPO groups, p<0.01 in EPO + vitamin E group). CAT activities in EPO and EPO + vitamin E groups were increased when compared to the untreated group (p<0.01).

In conclusion, our findings have shown that antioxidant status decreased and lipid peroxidation increased in hemodialysis patients. EPO has an antioxidant effect on the RBC and plasma antioxidant status, and plasma lipid peroxidation. These effects were moderately increased by the combination of vitamin E and EPO.  相似文献   
90.
The purpose of this study was to ascertain whether vitamin C supplementation during chronic exercise training alters rat brain antioxidant content. Female Wistar albino rats were exercised on a treadmill for 30 min/day for 6.5 weeks and were administered daily intraperitoneal injections of vitamin C (20 mg/kg). After the training period, chronically exercised rats showed no significant changes in total brain thiobarbituric acid reactive substances (TBARS) levels. In contrast, rats supplemented with vitamin C during the training period showed significantly elevated brain TBARS levels. If such results were extrapolated to man, where vitamin supplementation is a common practice, this would indicate that vitamin C supplementation may not protect brain tissue against exercise-induced oxidative damage, in such circumstances, this water-soluble antioxidant behaves as a pro-oxidant. (Mol Cell Biochem xxx: 135–138, 2005)  相似文献   
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