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991.
Fatemeh Zarei Namdar Yousofvand Mozafar Khazaei Ali Ghanbari 《Iranian Biomedical Journal》2013,17(4):221-224
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
992.
Ali Sayadmanesh Firouz Ebrahimi Abbas Hajizade Mosayeb Rostamian Hani Keshavarz 《Iranian Biomedical Journal》2013,17(4):165-170
Background: Botulinum neurotoxin (BoNT) complexes consist of neurotoxin and neurotoxin-associated proteins. Hemagglutinin-33 (HA-33) is a member of BoNT type A (BoNT/A) complex. Considering the protective role of HA-33 in preservation of BoNT/A in gastrointestinal harsh conditions and also its adjuvant role, recombinant production of this protein is favorable. Thus in this study, HA-33 was expressed and purified, and subsequently its antigenicity in mice was studied. Methods: Initially, ha-33 gene sequence of Clostridium botulinum serotype A was adopted from GenBank. The gene sequence was optimized and synthesized in pET28a (+) vector. E. coli BL21 (DE3) strain was transformed by the recombinant vector and the expression of HA-33 was optimized at 37°C and 5 h induction time. Results: The recombinant protein was purified by nickel nitrilotriacetic acid agarose affinity chromatography and confirmed by immunoblotting. Enzyme Linked Immunoassay showed a high titer antibody production in mice. Conclusion: The results indicated a highly expressed and purified recombinant protein, which is able to evoke high antibody titers in mice. Key Words: Botulinum neurotoxin, Expression, Purification 相似文献
993.
Elham Sadat Yazdi Almodarresi Javad Mokhtari Seyed Mohammad Taghi Almodarresi Mahdi Nouri Ali Shams Nateri 《Fibers and Polymers》2013,14(7):1196-1202
Conventional theory for color matching is Kubelka-Munk, but it fails in some situations. New intelligent procedures such as neural networks could learn the behavior of a complex system and produce accurate prediction. This paper investigates the ability of MLP (multiple layer perceptron) neural network for color matching of cotton fabric. Three reactive dyes, namely Levafix Red CA, Levafix Yellow CA and Levafix Blue CA were used for experiments. The dyed samples were scanned and L * a * b * histogram were extracted. Different neural networks were trained and tested using L * a * b * histogram of fabric’s images and also L * a * b * values (D65, 10°) of fabrics. The results were encouraging. For neural networks including the L * a * b * histogram in input vector, colorants and their concentration were predicted with a mean square error (MSE) less than 10?5 and an average value of color difference (CMC (1:2)) less than 1.5 for approximately 80 % of testing data. 相似文献
994.
The aim of this study was to compare the response surface regression and adaptive neuro-fuzzy models for predicting the bursting strength of plain knitted fabrics. The prediction models are based on the experimental data comprising yarn tenacity, knitting stitch length and fabric GSM as input variables and fabric bursting strength as output/response variable. The models quantitatively characterize the non-linear relationship and interactions between the input and output variables exhibiting very good prediction ability and accuracy, with ANFIS model being slightly better in performance than the regression model. 相似文献
995.
996.
S. Liaquat Ali B.C. Mazumdar 《The Journal of Horticultural Science and Biotechnology》2013,88(5):805-807
SUMMARYPistillate seedling plants of the local cultivar of papaya ‘Deshi’, transplanted 40 d after sowing, were sprayed with aqueous solutions of IBA (25 and 50 ppm), GA3 (100 and 200 ppm), kinetin (50 and 100 ppm), BA (25 and 50 ppm), ethephon (100 and 200 ppm) or with water (control) 100 d after transplanting, when the experimental fruits borne by them were 15 d old. Latex was collected from the fruits when they were 90-95 d old and continued on four occasions, at 7 d intervals. Highly significant increases in yield and in protease activity of the latex over the control was obtained by application of ethephon. IBA and GA, also increased latex production, but spraying the plants with kinetin or BA solutions gave no clear results 相似文献
997.
Bin Li Baoping Liu Changlin Shan Muhammad Ibrahim Yihan Lou Yangli Wang Guanlin Xie Hong‐ye Li Guochang Sun 《Pest management science》2013,69(2):312-320
BACKGROUND: Bacterial leaf blight and leaf streak are the two most damaging bacterial diseases of rice. However, few bactericidal chemicals are available for controlling both diseases. The antibacterial properties of two kinds of chitosan with different molecular weights and degrees of N‐deacetylation and their effect on rice bacterial leaf blight and leaf streak were evaluated. RESULTS: Results showed that the two kinds of chitosan solution possess a strong antibacterial activity against both rice bacterial pathogens and significantly reduced disease incidence and severity by comparison with the control under greenhouse conditions. However, the interaction between chitosan and rice pathogens was affected by the type and concentration of chitosan, the bacterial species and the contact time between chitosan and bacteria. The direct antibacterial activity of chitosan may be attributed to both membrane lysis and the destruction of biofilm. In addition, both chitosan solutions significantly increased the activities of phenylalanine ammonia lyase, peroxidase and polyphenol oxidase in rice seedlings following inoculation of two rice pathogens by comparison with the control. CONCLUSION: The role of chitosan in protection of rice against bacterial pathogens has been shown to involve direct antibacterial activity and indirect induced resistance. Copyright © 2012 Society of Chemical Industry 相似文献
998.
Cline Moriou Damien Lacroix Sylvain Petek Amr El-Demerdash Rozenn Trepos Tinihauarii Mareva Leu Cristina Florean Marc Diederich Claire Hellio Ccile Debitus Ali Al-Mourabit 《Marine drugs》2021,19(3)
Chemical investigation of the South-Pacific marine sponge Suberea clavata led to the isolation of eight new bromotyrosine metabolites named subereins 1–8 (2–9) along with twelve known co-isolated congeners. The detailed configuration determination of the first representative major compound of this family 11-epi-fistularin-3 (11R,17S) (1) is described. Their chemical characterization was achieved by HRMS and integrated 1D and 2D NMR (nuclear magnetic resonance) spectroscopic studies and extensive comparison with literature data. For the first time, a complete assignment of the absolute configurations for stereogenic centers C-11/17 of the known members (11R,17S) 11-epi-fistularin-3 (1) and 17-deoxyfistularin-3 (10) was determined by a combination of chemical modifications, Mosher’s technology, and ECD spectroscopy. Consequently, the absolute configurations of all our new isolated compounds 2–9 were determined by the combination of NMR, Mosher’s method, ECD comparison, and chemical modifications. Interestingly, compounds 2–7 were obtained by chemical transformation of the major compound 11-epi-fistularin-3 (1). Evaluation for acetylcholinesterase inhibition (AChE), DNA methyltransferase 1 (DNMT1) modulating activity and antifouling activities using marine bacterial strains are also presented. 相似文献
999.
We evaluated the factors influencing the adoption of rice-fish farming in the Tavalesh region near the Caspian Sea in northern Iran.We conducted a survey with open-ended questions.Data were collected from 184 respondents(61 adopters and 123 non-adopters) randomly sampled from selected villages and analyzed using logistic regression and multi-response analysis.Family size,number of contacts with an extension agent,participation in extension-education activities,membership in social institutions and the presence of farm workers were the most important socio-economic factors for the adoption of rice-fish farming system.In addition,economic problems were the most common issue reported by adopters.Other issues such as lack of access to appropriate fish food,losses of fish,lack of access to high quality fish fingerlings and dehydration and poor water quality were also important to a number of farmers. 相似文献
1000.
AnnaLotta Schiller Vestergren Sofia Trattner Jinfeng Pan Pernilla Johnsson Afaf Kamal-Eldin Eva Brännäs Ali A. Moazzami Jana Pickova 《Aquaculture International》2013,21(4):843-859
Sesamin (S) is a known lipid modulator and has been shown to increase the conversion of α-linolenic acid (ALA) to docosahexaenoic acid in rainbow trout (Oncorhynchus mykiss) fed vegetable oil mixtures including linseed oil. In this study, we evaluated the effects of S supplementation in linseed oil-based diets, content of α- and γ-tocopherols, fatty acid (FA) composition, as well as the gene expression of lipid-related genes. Fish with an average weight of 36.5 g were fed different combinations of commercial linseed oil (LO), purified linseed oil triacylglycerols (TAG) with polar fraction removed and a mixed linseed-sunflower oil (6:4 v/v) (MO). S was added at 0.58 g 100?1g feed and fed to the fish for a period of 58 days. Expression of PPARα was downregulated in white muscle of fish fed S containing diets (P < 0.05). The expression of PPARβ1A was not affected by S supplementation except where TAG oil was used. The expression of PPARβ1A declined significantly in TAG + S fed group (P < 0.05), which indicates that some minor compounds in linseed oil might suppress the effect of S on the expression of PPARβ1A. The expression of PPARγ(long) declined in LO + S and MO + S fed group (P < 0.05). The β-oxidation-related genes CPT1 and ACO were upregulated by vegetable oils compared to fish oil. S decreased percentage of ALA in white muscle of fish fed LO + S (P < 0.05). The increased desaturation index and the decreased ALA levels suggest that S may increase the biosynthesis of highly unsaturated FA in rainbow trout. 相似文献