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51.
The presence and vasoactive effects of native calcitonin gene-related peptide (CGRP), substance P (SP), and neurokinin A (NKA) were studied on isolated small branches of the coeliac artery from Atlantic cod, Gadus morhua, using immunohistochemistry and myograph recordings, respectively. Immunohistochemistry revealed nerve fibers containing CGRP- and SP/NKA-like material running along the wall of the arteries. CGRP induced vasorelaxation of precontracted arteries with a pD2 value of 8.54 ± 0.17. Relaxation to CGRP (10−8 M) was unaffected by l-NAME (3 × 10−4 M) and indomethacin (10−6 M) suggesting no involvement of nitric oxide or prostaglandins in the CGRP-induced relaxation. SP and NKA (from 10−10 to 3 × 10−7 M) contracted the unstimulated arteries at concentrations from 10−8 M and above in 42% and 33%, respectively, of the vessels. It is concluded that the innervation of the cod celiac artery includes nerves expressing CGRP-like and tachykinin-like material, and that a vasodilatory response to CGRP is highly conserved amongst vertebrates while the response to tachykinins is more variable.  相似文献   
52.
A total of 810 dairy cattle were blood sampled and used to evaluate serological screening for Neospora caninum infection in dairy cattle herds in Mashhad (Khorasan province, Iran). In 4 herds, of the 810 cattle, 123 (15.18%) were seropositive by IFA Test (VMRD Inc., Pullman, WA 99163, USA) with titer 1:200 and range of prevalence per herd from 9.92 to 19.60%. Seroprevalence was not significantly different between Holstein breed (14.88%) and Brown Swiss breed (19.60%). Comparison of N. caninum serological status with age groups (< or =2 years, 2-4 years, > or =4 years) showed no significant difference. Of the 139 aborted cattle sampled, 19.42% were seropositive for N. caninum.  相似文献   
53.
Property rights, the agricultural price index, forest area, population, income and timber price are important factors in the deforestation process. The aim of this study was to test the impact of these factors on deforestation in Iran using an environmental Kuznets curve (EKC). The autoregressive distributed lag approach was also used to estimate the deforestation function. The existence of an inverted U-shaped EKC for deforestation in Iran was confirmed. In addition, there is evidence of a relationship between deforestation and property rights, forest area, agricultural price index and terms of trade. It is concluded that improvement of secure property rights and environmental policies can improve compliance regarding forest land use and reduce the deforestation rate in Iran.  相似文献   
54.
The aim of this study was to investigate the cytotoxic and anticancer activities of stylosin, a monoterpene extracted from an edible plant, Ferula ovina, on 5637 and HFF3 cells using MTT and comet assays and DAPI staining.To assess stylosin effects, cells were cultured in the presence of various concentrations of stylosin during three days; the IC50 of stylosin on cancerous 5637 cells was less than its value on HFF3 normal cells, indicating that it might have anticancer properties. Investigating the mechanism of stylosin action revealed that it quickly induced DNA lesions and increased the number of apoptotic cells.  相似文献   
55.
Tropical Animal Health and Production - The National Bovine Tuberculosis (bTB) Eradication Program for dairy cattle has been operating in Taiwan for many years and has allowed the prevalence of bTB...  相似文献   
56.
Chronic inflammation, as reflected by increased level of acute phase protein such as C-reactive Protein (CRP) is highly prevalent in hemodialysis patients. CRP is a strong predictor of overall and cardiovascular mortality and morbidity in hemodialysis patients. This research was conducted to determine the C-reactive Protein (CRP) levels and its correlation to demographic and clinical characteristics and Laboratory values in hemodialysis patients in Sari, Iran. In a cross sectional study, 147 hemodialysis patients were studied. Patients' demographic and clinical data were recorded and also serum CRP, Cholesterol, Albumin, Phosphorous, Calcium, Hemoglobin and Hematocrit levels were measured. Overall, the mean CRP concentration was 15.8 mg L(-1). With considering to the different cutoff point (5, 6.2, 10 mg L(-1)) for CRP level, 107 patients (72.8%) had CRP level >5 mg L(-1), 99 patients (67.3%) had CRP level > 6.2 mg L(-1) and 77 patients (52.4%) had CRP level >10 nmg L(-1). The CRP levels greater than 6.2, had a direct statistically significant correlation with duration of hemodialysis and phosphorus level (p = 0.01). Also, CRP levels above 10 mg L(-1) had a direct statistically significant correlation with age and phosphorus levels (p = 0.02). According to the prevalence of high CRP level and it's correlation with age, duration ofhemodialysis and phosphorus level in hemodialysis patients, CRP level should be screened in this group of patients routinely because of its prognostic importance.  相似文献   
57.
Biodegradable edible sub-micron electrospun zein fibers were prepared using acetic acid as solvent. The solution concentration at three levels: 22, 26 and 30 w/v %, the electrospinning voltage at three levels: 10, 20 and 30 kV, the solution flow rate at three levels: 4, 8 and 12 ml/h and the distance between needle tip and collector at three levels: 10, 15 and 20 cm were studied. Central composite design (CCD) was utilized to modeling the effect of electrospinning parameters of zein solution on average fiber diameters and the data were analyzed using response surface methodology (RSM). Coefficient of determination, R2, of fitted regression model was higher than 0.9 for response. The analysis of variance table showed that the lack of fit was not significant for response surface model at 95 %. Therefore, the model for response variable was highly adequate. Results also indicated that the solution concentration had significant influence (P<0.0001) on morphology and diameter of fibers. By increasing the solution concentration, uniform and bead-free fibers were obtained. As the solution concentration was increased, the average fiber diameters were also increased. Furthermore, the electrospinning voltage had significant effect (P<0.0001) on average fiber diameters. By increasing the electrospinning voltage, the average fiber diameters increased. The solution flow rate and the distance between needle tip and collector had no significant influence on the average fiber diameters. According to model optimization, the minimum average fiber diameter of electrospun zein fiber is given by following conditions: 24 w/v % zein concentration, 10 kV of the applied voltage, 10 cm of needle tip to collector distance, and 4 ml/h of solution flow rate.  相似文献   
58.
The supercritical fluid extraction (SFE) of the aerial parts of Perovskia atriplicifolia Benth. was studied. The effect of different parameters such as pressure, temperature, modifier identity, and modifier volume on the SFE of the plant was investigated. The extracts were analyzed by GC and GC-MS and compared with the essential oil obtained from P. atriplicifolia Benth by steam distillation. The supercritical extracts and the steam-distilled products had very different compositions. The main constituents of the oil obtained by steam distillation were 1,8-cineole, limonene, camphor, beta-caryophyllene, alpha-pinene, camphene, and alpha-humulene. On the other hand, the major components of SFE extracts were 1,8-cineole, limonene, camphor, beta-caryophyllene, gamma-cadinene, alpha-pinene, and alpha-terpinyl acetate. The results showed that increasing the temperature from 35 to 65 degrees C (at a constant pressure of 100 atm) drastically reduced the number of extracted components. Also, the number of extracted constituents and the percent of main analytes increased when lower pressures were used. Using different modifiers (e.g., methanol, ethanol, dichloromethane, and hexane) for the extraction of the plant at low pressure (100 atm) and temperature (35 degrees C) showed that hexane was more selective than the other modifiers.  相似文献   
59.
Genetic Resources and Crop Evolution - Marrubium L., is a problematic genus of Lamiaceae family with approximately 40 taxa that some of its species grow in Iran. In the current study, we studied...  相似文献   
60.
Background:hESCs-MSCs open a new insight into future cell therapy applications, due to their unique characteristics, including immunomodulatory features, proliferation, and differentiation. Methods:Herein, hESCs-MSCs were characterized by IF technique with CD105 and FIBRONECTIN as markers and FIBRONECTIN, VIMENTIN, CD10, CD105, and CD14 genes using RT-PCR technique. FACS was performed for CD44, CD73, CD90, and CD105 markers. Moreover, these fibroblast-like cells, due to multipotent characteristics, differentiated to the osteoblast. Results:MSCs were derived from diploid and triploid hESC lines using sequential 3D and 2D cultures and characterized with the specific markers. IF showed the expression of FIBRONECTIN and CD105 in hESCs-MSCs. Flow cytometry data indicated no significant difference in the expression of MSC markers after 6 and 13 passages. Interestingly, gene expression profiles revealed slight differences between MSCs from diploid and triploid hESCs. The hESCs-MSCs displayed osteogenic differentiation capacity, which was confirmed by Alizarin red staining. Conclusion:Our findings reveal that both diploid and triploid hESC lines are capable of forming MSCs; however, there are some differences in their gene expression profiles. Generation of MSCs from hESCs, as a non-invasive procedure in large scale, will lend itself for the future cell-based therapeutic applications. Key Words: Human embryonic stem cells, Mesenchymal stem/stromal cells, Regenerative medicine  相似文献   
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