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41.
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   
42.
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   
43.
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   
44.
Abstract

For plant growth and composition, the effects of fertilizers including blood meal (BLO), cottonseed meal (CSM), dehydrated cow manure (COW), and urea (UREA) factored with lettuce (Lactuca sativa L.) of different morphological phenotypes including iceberg, romaine, loose head, and loose leaf were studied in a greenhouse. Lettuce growth increased with increasing nitrogen (N) applications from 0 to 800?mg N/pot (kg), but the top application of BLO, CSM, or UREA suppressed yields. Lettuce grown with BLO, CSM, or UREA had higher concentrations of N than with COW. Nitrate-N concentration in leaves of all varieties exceeded some standards at high application of organic fertilizer or urea except for COW. In general, increasing N application resulted in higher concentration of NH4-N in lettuce with increases in applications of fertilizers. Organic fertilizers and urea were equally effective in supporting growth and affecting nutrient accumulation in lettuce if sufficient N was supplied.  相似文献   
45.
European Journal of Plant Pathology - In this study, inhibitory effects of the aqueous and ethanolic leaf extracts obtained from marshmallow (A. officinalis) were evaluated against Alternaria spp.,...  相似文献   
46.
Background: Although effects of trace elements on secretion of sex steroids and insulin have been studied, the effects of these hormones on serum level of trace elements have been rarely investigated. The aim of the present study was to evaluate the effect of testosterone and finasteride administration and castration on serum levels of testosterone, insulin, zinc and chromium. Methods: Male adult rats (n = 32) were divided into 4 groups (n = 8). Group 1, control; Group 2, castration, castration was done at the first day of the study; Group 3, finasteride (20 mg/kg/day, dissolved in drinking water) and Group 4, testosterone (5 mg/kg/day, i.p.). At the end of the period of the study (35 days), serum testosterone, insulin, zinc and chromium levels were determined in the blood samples collected directly from the right atrium of the heart of the animals. Results: The data indicated that the serum levels of testosterone, insulin and zinc were significantly increased (P<0.01) in testosterone-administrated and finasteride groups, but the level of chromium was decreased in both groups (P<0.01). Castrated group had the lowest serum levels of testosterone, insulin and zinc (P<0.05). Also, the levels of serum chromium in this group were increased. Conclusion: The study demonstrates that testosterone and finasteride increases insulin and zinc levels and decreases chromium levels in the serum of male adult rats. According to these data, it seems that testosterone may affect glucose cycle through effect on serum insulin levels and trace elements such as zinc and chromium. Key Words: Finasteride, Castration, Insulin, Zinc, Chromium  相似文献   
47.
Background: The secretion of thyroxin (T4) as the main hormone of thyroid gland is regulated by androgens. The present study aimed to evaluate the effect of testosterone and finasteride administration and castration on serum levels of T4 and to show the effect of this regulation on total body weight, weight of testis, and the weight of prostate. Methods: Male adult rats (n = 32) were divided into 4 groups (n = 8): Group 1 (control), Group 2 (castration), Group 3 (finasteride: 20 mg/kg/day) and Group 4 (testosterone: 5 mg/kg/day). At the end of the study (35 days), serum level of thyroxin, body weight, weight of testis, and prostate were determined. Results: The data showed that the body weight increased in castrated (P = 0.04) and decreased in testosterone (P = 0.00) groups but did not differ in finasteride (P>0.05) group. There were not any differences in the weight of testis among control, finasteride, and testosterone groups but the weight of prostate increased in testosterone group (P = 0.00) and decreased in castrated (P = 0.03) and finasteride groups (P = 0.04). In addition, the serum level of T4 (nmo/ml) decreased in the three groups: finasteride (P = 0.03), testosterone (P = 0.04), and castrated (P = 0.00). Conclusion: Testosterone in both high and low levels decreased the amount of T4 with a time-dependent manner. Key Words: Finasteride, Rats, Testosterone, Thyroxin  相似文献   
48.
Journal of Crop Science and Biotechnology - Wheat is the most important food on earth. Therefore, to produce high-quality products with efficient utilization, the micronutrient groups are needed....  相似文献   
49.
Cyanobacteria are photosynthetic prokaryotic organisms which represent a significant source of novel, bioactive, secondary metabolites, and they are also considered an abundant source of bioactive compounds/drugs, such as dolastatin, cryptophycin 1, curacin toyocamycin, phytoalexin, cyanovirin-N and phycocyanin. Some of these compounds have displayed promising results in successful Phase I, II, III and IV clinical trials. Additionally, the cyanobacterial compounds applied to medical research have demonstrated an exciting future with great potential to be developed into new medicines. Most of these compounds have exhibited strong pharmacological activities, including neurotoxicity, cytotoxicity and antiviral activity against HCMV, HSV-1, HHV-6 and HIV-1, so these metabolites could be promising candidates for COVID-19 treatment. Therefore, the effective large-scale production of natural marine products through synthesis is important for resolving the existing issues associated with chemical isolation, including small yields, and may be necessary to better investigate their biological activities. Herein, we highlight the total synthesized and stereochemical determinations of the cyanobacterial bioactive compounds. Furthermore, this review primarily focuses on the biotechnological applications of cyanobacteria, including applications as cosmetics, food supplements, and the nanobiotechnological applications of cyanobacterial bioactive compounds in potential medicinal applications for various human diseases are discussed.  相似文献   
50.
Background: To develop a new green approach for biosynthesis of silver nanoparticles, myconanotechnology has been represented as a novel field of study in nanotechnology. In this study, we have reported the extracellular synthesis of highly stable silver nanoparticles using three species of dermatophytes: Trichophyton rubrum, Trichophyton mentagrophytes and Microsporum canis. Methods: Clinical strains of these species were grown in a liquid medium containing mineral salt and incubated at 25°C for 5-7 days. The cell-free filtrate of each culture was obtained and subjected to synthesize silver nanoparticles in the presence of 1 mM AgNO3. Results: The reduction of Ag+ ions in metal nanoparticles was investigated virtually by tracing the solution color which was switched into reddish-light brown after 72 h. For T. mentagrophytes, a UV-visible spectra demonstrating a strong, quite narrow peak located between 422 and 425 nm was obtained. For M. canis, a fairly wide peak centering at 441 nm and for T. rubrum, a weak spectrum to decipher were observed. According to transmission electron microscopy (TEM) results, fairly uniform, spherical, and small in size with almost less than 50 nm particles were forms in case of T. mentagrophytes. For the other two species, TEM images showed existence of small spherical nanosilvers but not as small as nanoparticles synthesized by T. mentagrophytes. Conclusion: We observed that species belong to a single genus of the fungi have variable ability to synthesize silver nanoparticles extracellulary with different efficiency. Furthermore, the extracellular synthesis may make the process simpler and easier for following processes.Key Words: Nanoparticles, Dermatophytes, Extracellular biosynthesis  相似文献   
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