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1.
Summary Autotetraploids were established from 8 diploid wild species of section Arachis. In all the autotetraploids the chromosomes paired largely as bivalents even though they possess the ability to pair as multivalents. Pollen and pod fertility in the C1 generation were not directly associated with chromosome pairing. The C2 generation autotetraploids showed a gradual increase in bivalent associations and pollen and pod fertility. The identification of two genomes, A and B, in the diploid species and in the tetraploid, A. hypogaea, of the section Arachis, a fairly good crossability, and the type of chromosome associations observed in hybrids between A. hypogaea and the autotetraploids of wild Arachis species indicated good prospects of utilizing autotetraploids as genetic bridges in transferring desired traits from these taxa into groundnut.Submitted as Journal Article No. 516 by International Crops Research Institute for the Semi-Arid Tropics (ICRISAT)  相似文献   
2.
Treatment of newborn rats with clomiphene citrate during the first 5 days of life gave rise to a marked decrease in body mass and to a still greater decrease in gonadal mass. A decrease was also observed in the testicular diameter of the males. The females showed a 43% increase in their estradiol levels over the control and an increase in the sensitivity to gonadotropins. Thyroxine level, which was also determined in view of the known gonadotropin-thyrotropin overlap, showed no change 6 weeks after pretreatment with clomiphene, while the thyroid gland responded to gonadotropin in the same manner as to thyrotropin.  相似文献   
3.
Ensuring food security for the rapidly increasing population and changing climatic scenarios are requisites for exploiting the genetic divergence of food crops. A study was undertaken to sort out an early maturing chickpea variety for fitting easily between rice-rice cropping systems in the Eastern Indo-Gangetic Plain of Bangladesh. The trial was comprised of eight elite lines of chickpea and executed at various localities in Bangladesh from 2014– 15 to 2017–18. The result explored the chickpea genotype, BARI Chola-11 remained superior to the rest of the elite genotypes for having a short maturity period (100–106 days), and lesser days to 50% flowering (47– 55 days). The same genotype was recorded to have robust vegetative and reproductive yield attributes including plant height (49–57 cm), podsplant−1 (37–50), and optimum 100 seed weight (19.5–20.6 g). Owing to better yield attributes, BARI Chola-11 resulted in the maximum seed yield (1200–1500 kg ha−1 ) of chickpea and might be recommended for general adoption in the region for boosting nutritional security status through improved productivity under changing climate.  相似文献   
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5.
AH 22216 is a new histamine-H2-receptor antagonist which possesses a triazole ring. When compared to cimetidine, AH 22216 is about 100 times more potent (Ki = 0.21×10–8 M) in inhibiting histamine-stimulated acid secretion in isolated rabbit gastric cells. These two antihistamines have no effect on carbachol-stimulated acid secretion in the system. The data indicate that AH 22216 interacts directly and specifically on the gastric H2-receptor of the parietal cell and are consistent with the reported pharmacological potencies of AH 22216 and cimetidine on histamine-induced gastric-acid secretion in vivo. AH 22216 could thus be a useful therapeutic agent in patients with peptic ulcers.  相似文献   
6.
Different growth factors can regulate stem cell differentiation. We used keratinocyte growth factor (KGF) to direct adipose‐derived stem cells (ASCs) differentiation into keratinocytes. To enhance KGF bioavailability, we targeted KGF for collagen by fusing it to collagen‐binding domain from Vibrio mimicus metalloprotease (vibrioCBD‐KGF). KGF and vibrioCBD‐KGF were expressed in Escherichia coli and purified to homogeneity. Both proteins displayed comparable activities in stimulating proliferation of HEK‐293 and MCF‐7 cells. vibrioCBD‐KGF demonstrated enhanced collagen‐binding affinity in immunofluorescence and ELISA. KGF and vibrioCBD‐KGF at different concentrations (2, 10, and 20 ng/ml) were applied for 21 days on ASCs cultured on collagen‐coated plates. Keratinocyte differentiation was assessed based on morphological changes, the expression of keratinocyte markers (Keratin‐10 and Involucrin), and stem cell markers (Collagen‐I and Vimentin) by real‐time PCR or immunofluorescence. Our results indicated that the expression of keratinocyte markers was substantially increased at all concentrations of vibrioCBD‐KGF, while it was observed for KGF only at 20 ng/ml. Immunofluorescence staining approved this finding. Moreover, down‐regulation of Collagen‐I, an indicator of differentiation commitment, was more significant in samples treated with vibrioCBD‐KGF. The present study showed that vibrioCBD‐KGF is more potent in inducing the ASCs differentiation into keratinocytes compared to KGF. Our results have important implications for effective skin regeneration using collagen‐based biomaterials.  相似文献   
7.
Bacillus pumilus SG2 isolated from high salinity ecosystem in Iran produces two chitinases (ChiS and ChiL) and secretes them into the medium. In this study, chiS and chiL genes were cloned in pQE-30 expression vector and were expressed in the cytoplasm of Escherichia coli strain M15. The recombinant proteins were purified using Ni-NTA column. The optimum pH and optimum temperature for enzyme activity of ChiS were pH 6, 50°C; those of ChiL were pH 6.5, 40°C. The purified chitinases showed antifungal activity against Fusarium graminearum, Rhizoctonia solani, Magnaporthe grisea, Sclerotinia sclerotiorum, Trichoderma reesei, Botrytis cinerea and Bipolaris sp. Moreover, purified ChiS was identified as chitinase/lysozyme, which are capable of degrading the chitin component of fungal cell walls and the peptidoglycan component of cell walls with many kinds of bacteria (Xanthomonas translucens pv. hordei, Xanthomonas axonopodis pv. citri, Bacillus licheniformis, E. coli C600, E. coli TOP10, Pseudomonas aeruginosa and Pseudomonas putida). Strong homology was found between the three-dimensional structures of ChiS and a chitinase/lysozyme from Bacillus circulans WL-12. This is the first report of a bifunctional chitinase/lysozyme from B. pumilus.  相似文献   
8.
International Journal of Peptide Research and Therapeutics - The aim of the current study was to determine effect of in ovo feeding of vitamin B12 on hatchability, growth performance and blood...  相似文献   
9.
Abstract

Betulin (B) and betulinic acid (BA) are two triterpenoids with a wide range of biological and medicinal activities in different organs of Betula pendula. This research aimed to increase the accumulation of B and BA in the hairy root culture of B. pendula by seven biotic and abiotic elicitors. Hairy root was induced in the stem’s inner bark of B. pendula using the C58C1 strain in the WPM (Woody Plant Medium). The effects of different concentrations of elicitors and different time of root harvest in hairy root culture of B. pendula showed that highest level of growth index (GI), B, and BA was acquired in treated hairy roots with chitosan (CTS), chlorocholine chloride (CCC) and chitosan nano-fiber (CTS NF). Highest GI of B. pendula hairy roots was 13 that was obtained in the roots treated with CTS 150?mg l?1 on the 8th day. The highest content of BA was 1.3?mg g?1 DW after treatment with 1?mg l?1CCC on the 4th and 6th days and 200?mg l?1CTS NF on the 10th day. The highest B content (0.94?mg g?1DW) was obtained in the treated hairy root by 2?mg l?1 CCC after 4 and 6?days.  相似文献   
10.
The production of highly efficient, recyclable and cost-effective enzymes is one of the most important goals in industrial biotechnology. Bacterial spores are highly resistant to harsh environmental conditions, easy to produce and are suitable for manipulation of genetic materials. These features make them a very efficient tool for biotechnology. Here, we show the use bacterial spores for presentation of functional enzyme. Spore coat display was used to produce a biocatalyst, which expresses β-galactiosidase (LacA). This enzyme is commonly used to produce lactose-free milk for lactose intolerant individuals. The lacA gene from Bacillus subtilis strain 168 was expressed on the surface of B. subtilis RH101(ΔcotC) spores using CotC as protein carrier. Presence of LacA protein is verified by western blotting. Results of β-galactiosidase assay show that the expressed enzyme retained its activity in condition of freezing and drying, as well as after recovery from the reaction’s mixture.  相似文献   
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