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31.
Amin B  Hosseinzadeh H 《Fitoterapia》2012,83(5):888-895
The current study was designed to evaluate therapeutic potential of systemically administered ethanolic and aqueous extracts of saffron as well as its bioactive ingredients, safranal and crocin, in chronic constriction injury (CCI)-induced neuropathic pain in rats. The von Frey filaments, acetone drop, and radiant heat test were performed to assess the degree of mechanical allodynia, thermal allodynia and thermal hyperalgesia respectively, at different time intervals, i.e., one day before surgery and 3, 5, 7 and 10 days post surgery. The ambulatory behavior was evaluated using the open field test. A 7-day treatment with the ethanolic and aqueous extracts (50,100 and 200 mg/kg, i.p.) and safranal (0.025, 0.05 and 0.1 mg/kg, i.p.), attenuated the behavioral symptoms of neuropathic pain in a dose dependent manner. Crocin even at the high dose (50 mg/kg) failed to produce any protective role. However, gabapentine (100 mg/kg) as a reference drug significantly alleviated all behavioral manifestations of neuropathic pain compared to control group. In conclusion, the results of this study suggest that ethanolic and aqueous extracts of saffron as well as safranal could be useful in treatment of different kinds of neuropathic pains and as an adjuvant to conventional medicines.  相似文献   
32.
In the present study the interaction of three genetically different clonal cultures of Trichomonas gallinae and Tetratrichomonas gallinarum with a permanent chicken liver (LMH) and a permanent quail fibroblast (QT35) cell culture was studied. Proliferation of T. gallinae cells was associated with a disintegration of the cell monolayer. The initial lesions on the LMH monolayer consisted of a progressive accumulation of the flagellate, forming clumps attached to the monolayer. A prolonged incubation time was characterized by appearance of holes in the cell monolayer with accumulation of trichomonads at their periphery. According to the severeness of the monolayer disruption differences among three tested T. gallinae clones were noticed. Furthermore, filtrates obtained either from axenic cultures of T. gallinae or from infected cell cultures produced a cytopathogenic effect similar to the protozoal cells, on both types of cell cultures. However, the destructive effect of the flagellates and their cell-free filtrates was much more pronounced on the LMH monolayer in comparison with the QT35 cells. Furthermore, freshly seeded LMH and QT35 cells suspended in cell-free filtrates of T. gallinae were unable to form a confluent monolayer. In comparison to T. gallinae, clonal cultures of T. gallinarum or their cell-free filtrates produced no effect on both types of monolayers. Interestingly, the cell-free filtrates obtained from both trichomonad species had an effect on the viability of both cell cultures. However, the cytotoxic effect of T. gallinarum filtrates was less severe than that recorded by T. gallinae. Consequently, for the first time a destruction of specified monolayers induced by T. gallinae-free filtrates could be demonstrated.  相似文献   
33.
The purpose of this study was to establish normal physiologic reference values for intraocular pressure (IOP) and Schirmer tear test (STT) results in clinically normal ostriches (Struthio camelus). Twenty ostriches of both sexes, 10 juveniles (1.5-2 yr of age) and 10 adults, were included in this study. Complete ophthalmic examination was performed prior to this investigation. STT was performed by inserting a standard sterile STT strip over the ventral lid margin into the ventral conjunctival sac for 60 sec. Following the STT, IOP was measured using applanation tonometry with the Tono-Pen Vet tonometer after topical instillation of one drop of 0.5% proparacaine ophthalmic solution. The mean +/- SD and range of Tono-Pen readings of IOP for all birds was 18.8 +/- 3.5, with a range of 12-24. Mean IOP in juvenile ostriches was 19.7 +/- 3.6. Mean IOP in adult ostriches was 16.9 +/- 2.9. There was no statistically significant difference between young and adult birds (P = 0.07). The mean STT values in the present study were 16.3 +/- 2.5 mm/1 min when measurements from both eyes were averaged. Mean STT in juvenile and adult ostriches was 15.4 +/- 1.8 and 17.2 +/- 2.9 mm/1 min, respectively. There was no statistically significant difference between young and adult birds (P = 0.11). No statistically significant differences between genders were found for any of the results (P > or = 0.41). In conclusion, this study provides normal reference range values for STT and IOP in clinically healthy ostriches.  相似文献   
34.
An unsolved problem in the digital mapping of categorical soil variables and soil types is the imbalanced number of observations, which leads to reduced accuracy and the loss of the minority class (the class with a significantly lower number of observations compared to other classes) in the final map. So far, synthetic over- and under-sampling techniques have been explored in soil science; however, more efficient approaches that do not have the drawbacks of these techniques and guarantee retention of the minority classes in the produced map are essentially required. Such approaches suggested in the present study for digital mapping of soil classes include machine learning models of ensemble gradient boosting, cost-sensitive learning and one-class classification (OCC) of the minority class combined with multi-class classification. In this regard, extreme gradient boosting (XGB) as an ensemble gradient learner, a cost-sensitive decision tree (CSDT) within the C5.0 algorithm, and a one-class support vector machine combined with multi-class classification (OCCM) were investigated to map eight soil great groups with a naturally imbalanced frequency of observations in northwest Iran. A total of 453 profile data points were used for mapping the soil great groups of the study area. A data split was done manually for each class separately, which resulted in an overall 70% of the data for calibration and 30% for validation. The bootstrapping approach of calibration (with 10 runs) was performed to produce multiple maps for each model. The 10 bootstraps were evaluated against the hold-out validation dataset. The average values of accuracy measures, including Kappa (K), overall accuracy (OA), producer's accuracy (PA) and user's accuracy (UA), were explored. In addition, the results of this study were compared with a previous study in the same area, in which resampling techniques were used to deal with imbalanced data for digital soil class mapping. The findings show that all three suggested methods can deal well with the imbalanced classification problem, with OCCM showing the highest K (= 0.76) and OA (= 82) in the validation stage. Also, this model can guarantee the retention of the minority classes in the final map. Comparing the present approaches with the previous study approach demonstrates that the three newly suggested methods can remarkably increase both overall and individual class accuracy for mapping.  相似文献   
35.
This study reports the results of an investigation aiming at finding what affect nano titania (TiO2) and nano strontium titanate (SrTiO3) on self-cleaning of cotton fabrics. The photocatalytic activity of nano strontium titanate has been examined on cotton fabric under UV irradiation in various concentrations in mixing of nano titania. The amount of loaded nano titania and nano strontium titanate particles on cotton fabrics were investigated using X-ray fluorescence spectrometry (XRF) and crystallinity of coatings by X-ray diffraction spectroscopy (XRD). The treated cotton fabrics, which were stained with two common synthesized dyes, were exposed to 400 W UV radiation for 30 hours and their self-cleaning property was investigated by a reflectance spectrophotometer. Scanning electron microscope (SEM) images show pervasion of nano materials on the surface of the treated cotton. Adding nano strontium titanate to nano titania showed the most promising photocatalytic activity toward dye degradation.  相似文献   
36.
Radical melt graft copolymerizations of poly (lactic acid) (PLA) with amide monomers using benzoyl peroxide as an initiator during reactive extrusion is studied. The effects of two monomer types at various concentrations, reaction temperatures and initiator concentrations on the grafting yield are investigated. The results showed that percentage of grafting was significantly enhanced by increasing benzoyl peroxide concentrations up to 12 mpm and then decreased by an increase in the initiator concentration. Furthermore, increasing each monomer concentration up to 450 mpm, improved the grafting yield significantly. Further increase brings about a marked fall in the grafting yield. Fourier Transform Infrared Spectroscopy (FTIR), back titration and nitrogen analyses confirmed that monomers of acrylamide and methacrylamide were successfully grafted onto PLA. The Gel Permeation Chromatography (GPC) data showed that the molecular weight of the grafted PLA samples under optimum conditions does not show any dramatic drop of PLA molecular weight by thermal degradation or hydrolysis of polyester chains, while the polydispersity index is poorly affected by the chemical modification of PLA. Also, the monomer structures affected the grafting yield as well as polymer chain combination. In addition under the same conditions, the grafting yield of acrylamide was more than that of methacrylamide. Thermal properties, molecular weight, density, moisture regain and tensile properties of the samples were also measured.  相似文献   
37.
The present study was conducted to compare the effects of xenogenic bovine fetal demineralized bone matrix (DBM), commercial DBM, omentum, omentum-calf fetal DBM, cortical autograft and xenogenic cartilage powder on the healing of tibial defects in a dog model to determine the best material for bone healing. Seven male adult mongrel dogs, weighing 26.2 ± 2.5 kg, were used in this study. Seven holes with a diameter of 4-mm were created and then filled with several biomaterials. Radiographs were taken postoperatively on day 1 and weeks 2, 4, 6, 8. The operated tibias were removed on the 56th postoperative day and histopathologically evaluated. On postoperative days 14, 42 and 56, the lesions of the control group were significantly inferior to those in the other group (p < 0.05). On the 28th postoperative day, the autograft group was significantly superior to the control and omentum groups (p < 0.05). Moreover, calf fetal DBM was significantly superior to the control group. There was no significant difference between the histopathological sections of all groups. Overall, the omentum and omentum-DBM groups were superior to the control group, but inferior to the autograft, commercial-DBM, calf fetal DBM and calf fetal cartilage groups.  相似文献   
38.
In ovo injection (IOI) of Naringin (N), flavanone was examined on post‐hatch blood biochemical parameters, antioxidant status and bone characteristics. Fertile eggs (n = 700) were distributed in seven groups with 100 eggs. On 14th and 17.5th days of incubation, four groups were injected using 15 or 30 mg active ingredient levels of naringin/0.5 ml saline/egg, low and high level, into amnion sac. Controls include sham (injected normal saline, 0.5 ml/egg on day 14 and 17.5th) and un‐injected group. IOI of high naringin and saline on 14th day of incubation resulted in lower hatchability and then higher mortality in last week of embryonic life. On day hatch, high levels of injected groups more body weight compared to the control. Chick length was increased at high levels of naringin on day 17.5th compared to control and saline injected. Quality traits of bones were improved in naringin‐injected groups compared to control. IOI of naringin influenced thyroid hormones on 14th day of incubation. Naringin groups influenced the Alkaline phosphatase (ALP), Calcium (Ca), superoxide dismutase (SOD), blood biochemical and lipids. Totally, amniotic IOI of naringin in last days of developing embryo may be useful for hatched chick, development of leg long bone or effect on biochemical metabolites by levels of flavanone that it needs more research.  相似文献   
39.
The effects of exogenous application of abscisic acid (ABA) on anti-oxidant enzyme activities and photosynthetic capacity in ‘Sultana’ grapevine (Vitis vinifera L.) were investigated under cold stress. When vines had an average of 15 leaves, 0 (control), 50, 100, or 200 µM ABA was sprayed to run-off on all leaves of each plant. Twenty-four hours after foliar spraying with ABA, half (n = 5) of the water-only control vines and half (n = 5) of each group of ABA-treated plants were subjected to 4°C for 12 h, followed by a recovery period of 3 d under greenhouse conditions (25°/18°C day/night). The remaining plants in each treatment group were kept at 24°C. Cold stress increased H2O2 and malondialdehyde (MDA) concentrations in vine leaves, whereas all foliar ABA treatments significantly reduced their levels. Chilled plants showed marked increases in their total soluble protein contents in response to each ABA treatment. ABA significantly increased the activities of superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase in cold-stressed grapevine leaves. In contrast, cold stress markedly decreased the rates of leaf photosynthesis (A) and evaporation (E), stomatal conductance (gs), and chlorophyll concentrations in leaves, but increased intercellular CO2 concentrations (Ci) in leaves. Treatment with all concentrations of ABA resulted in lower leaf A, E, and gs values, but higher Ci values at 24°C. However, following cold stress, ABA-treated vines showed higher leaf A, E, and gs values, but lower Ci values compared to control vines without ABA treatment. The application of 50–200 µM ABA allowed chilled vines to recover more quickly when re-exposed to normal temperatures, enabling the vines to resume their photosynthetic capacity more efficiently following cold stress. These results showed that, by stimulating anti-oxidant enzyme systems and alleviating cold-induced stomatal limitations, ABA reduced the inhibitory effect of cold stress on the rate of CO2 fixation in ‘Sultana’ grapevine plants.  相似文献   
40.
We used data from 144 bulls, heifers, and steers to determine the repeatability of ultrasound-predicted percentage of intramuscular fat and to study the effect of repeated measurements on the standard error of prediction. Animals were scanned at an average age of 433 d by a certified technician. Individual bulls, heifers, and steers were scanned five to six times each with two Aloka 500-V machines, and the percentage of intramuscular fat was predicted from two regions of interest within an image. Variance components and repeatability values were computed for the overall data and by machine, region of interest, and sex. Animals were broadly divided into two groups based on mean ultrasound-predicted percentage of intramuscular fat. Variance components and repeatability values were then estimated within each group. The overall repeatability of ultrasound-predicted percentage of intramuscular fat was .63 +/- .03. Differences in the repeatability values between machines and between regions of interest were not different from zero (P > .05). Bulls showed a lower within-animal SD of .82% as compared to .97 and 1.02% for steers and heifers, respectively. However, steer ultrasound-predicted percentage of intramuscular fat measures were more repeatable (P < .05) than those of bulls and heifers. The difference in repeatability between bull and heifer measures was not important (P > .05). Animals with mean ultrasound-predicted percentage of intramuscular fat less than 4.79% showed less repeatable measures (P < .05) than those with means above 4.79%. The image variance contributed to nearly 70% of the total variance of observations within an animal. Standard error of animal mean measures showed a 50% reduction when the number of images per animal increased to four. Therefore, we concluded that increasing the number of images per animal plays a more significant role in reducing the standard error of prediction than taking multiple measurements within a single image.  相似文献   
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