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21.
Eucalyptus nitens (Deane & Maiden) Maiden takes at least five years to initiate flower buds from seed and is an infrequent and light flowerer. Because this behavior constitutes a major impediment to breeding programs, we examined the mechanisms controlling floral induction in E. nitens, with the long-term aim of reducing generation time and increasing seed yield. Application of paclobutrazol reduced the concentration of endogenous gibberellic acid (GA) in apical tissue and enhanced the reproductive activity of grafted trees maintained outside over winter in Canberra, Australia. Grafts maintained in a warm greenhouse over winter did not produce flower buds, despite the paclobutrazol-induced reduction in GA concentration of the apical tissue. Exposing untreated grafts, which had been maintained over winter in a warm greenhouse, to low temperature the following spring reduced growth but did not induce flower bud production. Addition of GA(3) to paclobutrazol-treated grafts reduced the effect of paclobutrazol on reproductive activity. 相似文献
22.
Imtiaj Hasan Shigeki Sugawara Yuki Fujii Yasuhiro Koide Daiki Terada Naoya Iimura Toshiyuki Fujiwara Keisuke G. Takahashi Nobuhiko Kojima Sultana Rajia Sarkar M. A. Kawsar Robert A. Kanaly Hideho Uchiyama Masahiro Hosono Yukiko Ogawa Hideaki Fujita Jiharu Hamako Taei Matsui Yasuhiro Ozeki 《Marine drugs》2015,13(12):7377-7389
MytiLec; a novel lectin isolated from the Mediterranean mussel (Mytilus galloprovincialis); shows strong binding affinity to globotriose (Gb3: Galα1-4Galβ1-4Glc). MytiLec revealed β-trefoil folding as also found in the ricin B-subunit type (R-type) lectin family, although the amino acid sequences were quite different. Classification of R-type lectin family members therefore needs to be based on conformation as well as on primary structure. MytiLec specifically killed Burkitt''s lymphoma Ramos cells, which express Gb3. Fluorescein-labeling assay revealed that MytiLec was incorporated inside the cells. MytiLec treatment of Ramos cells resulted in activation of both classical MAPK/ extracellular signal-regulated kinase and extracellular signal-regulated kinase (MEK-ERK) and stress-activated (p38 kinase and JNK) Mitogen-activated protein kinases (MAPK) pathways. In the cells, MytiLec treatment triggered expression of tumor necrosis factor (TNF)-α (a ligand of death receptor-dependent apoptosis) and activation of mitochondria-controlling caspase-9 (initiator caspase) and caspase-3 (activator caspase). Experiments using the specific MEK inhibitor U0126 showed that MytiLec-induced phosphorylation of the MEK-ERK pathway up-regulated expression of the cyclin-dependent kinase inhibitor p21, leading to cell cycle arrest and TNF-α production. Activation of caspase-3 by MytiLec appeared to be regulated by multiple different pathways. Our findings, taken together, indicate that the novel R-type lectin MytiLec initiates programmed cell death of Burkitt’s lymphoma cells through multiple pathways (MAPK cascade, death receptor signaling; caspase activation) based on interaction of the lectin with Gb3-containing glycosphingolipid-enriched microdomains on the cell surface. 相似文献
23.
Mondal Satyen Jamil Hasan M. Ahmed Tofayel Giashuddin Miah M. C. Sta Cruz Pompe M. Ismail Abdel 《水稻科学》2020,27(6):515-528
Rice (Oryza sativa) plants acquired excess photosynthates in the form of nonstructural carbohydrates (NSCs) in their stems and grain. Despite keen interest in rice NSC, the dynamics of NSC accumulation, translocation and re-accumulation have not yet been well investigated. AG1 and AG2 QTLs associated with flooding tolerance through catalyzing starch into soluble sugar in germinating seeds. Here we conducted three experiments, greenhouse and field to lay the groundwork for large-scale diversity studies on grain NSC and some agronomic traits under direct-seeded rice (DSR) system, using elite lines incorporating AG1, AG2 and AG1-AG2 QTLs into the popular varieties PSB Rc82 and Ciherang-Sub1 along with the donors Kho Hlan On (AG1) and Ma-Zhan Red (AG2). In germinating seedlings, soluble sugars increased, while starch concentration decreased gradually especially in the tolerant checks and AG1-AG2 introgression lines under flooded soil. Soluble sugar accumulation in stem started to increase from the vegetative stage and peaked at the panicle initiation stage then gradually decreased towards the maturity stage. But Sub1-AG lines had higher sugar and starch concentrations at different growth stages than other genotypes in wet season 2016 and dry season 2017. Plant survival rate was positively correlated with the stem NSC at the early vegetative stage (21 days after sowing), and stem NSC was positively associated with plant height at different growth stages. Among the tested seeding rate, the most suitable seeding rate, 4 g/m2 with shallow burial depth (0.5 cm), resulted in better seedling establishment, relatively higher seedling vigor index and higher leaf area index under flooding in DSR system. Introgression of AG1-AG2 QTLs had no any negative impact on nonstructural carbohydrate, germination rate, and growth and biomass production. 相似文献
24.
Ozgun Kalkisim Duygu Ozdes Zuhal Okcu Besim Karabulut Hasan Basri Senturk 《Erwerbs-Obstbau》2016,58(1):41-48
The present study was conducted in order to determine the pomological and morphological characteristics and chemical compositions of some local apple varieties grown in Gumushane. As a result of field work in Gumushane province, sixteen different apples, which are Summer Apple, English apple, Green Belly, Black Belly and Yellow Belly Apples, Amasya Marble, Bey Apple, Chest Apple, Mahsusa, Arabian Girl, Willow Apple, Tav?anba??, Yellow H?d?r, Local Marble, Bride Apple, and Fatty Apple were collected in order to analyze. The average results of pomological and morphological properties and chemical compositions were obtained as following: fruit mass; 127.36 g, fruit width; 65.23 mm, fruit length; 57.30 mm, fruit stalk thickness; 2.17 mm, fruit stalk length; 17.63 mm, stalk pit depth; 12.75 mm, flower pit depth; 10.29 mm, fruit firmness; 13.79 kg/cm2, seed house width; 15.89 mm, seed house length; 17.39 mm, number of seeds; 4.3, water soluble dry matter content; 14.53?%, ash content; 1.11?%, pH; 3.8, titratable acidity; 0.69 g/L, water content; 83.8?%, reducing sugar; 5.04 g/100 g, sucrose; 2.25 g/100 g, and the amount of total sugars; 7.29 g/100. The fruit peel color was determined by considering the light transmittance (L). The average L values were ranged between 112.06 and 66.32. On the other hand among the mineral elements, potassium and manganese amounts were determined as the highest and the lowest, respectively. 相似文献
25.
Albasan H Lulich JP Osborne CA Lekcharoensuk C Ulrich LK Carpenter KA 《Journal of the American Veterinary Medical Association》2003,222(2):176-179
OBJECTIVE: To determine effects of storage temperature and time on pH and specific gravity of and number and size of crystals in urine samples from dogs and cats. DESIGN: Randomized complete block design. ANIMALS: 31 dogs and 8 cats. PROCEDURE: Aliquots of each urine sample were analyzed within 60 minutes of collection or after storage at room or refrigeration temperatures (20 vs 6 degrees C [68 vs 43 degrees F]) for 6 or 24 hours. RESULTS: Crystals formed in samples from 11 of 39 (28%) animals. Calcium oxalate (CaOx) crystals formed in vitro in samples from 1 cat and 8 dogs. Magnesium ammonium phosphate (MAP) crystals formed in vitro in samples from 2 dogs. Compared with aliquots stored at room temperature, refrigeration increased the number and size of crystals that formed in vitro; however, the increase in number and size of MAP crystals in stored urine samples was not significant. Increased storage time and decreased storage temperature were associated with a significant increase in number of CaOx crystals formed. Greater numbers of crystals formed in urine aliquots stored for 24 hours than in aliquots stored for 6 hours. Storage time and temperature did not have a significant effect on pH or specific gravity. CONCLUSIONS AND CLINICAL RELEVANCE: Urine samples should be analyzed within 60 minutes of collection to minimize temperature- and time-dependent effects on in vitro crystal formation. Presence of crystals observed in stored samples should be validated by reevaluation of fresh urine. 相似文献
26.
Riaz Hasan Keiichiro Nishimura Yoshiaki Nakagawa Norio Kurihara Tamio Ueno 《Pest management science》1996,46(3):221-225
N-Arylcarbamoylpyrazolines with various substituents at the para position of the carbamoyl benzene ring inhibited ATP-dependent Ca2+-uptake in synaptosomes prepared from the rat brain. The activity of these compounds was evaluated as log(1/I50), the reciprocal logarithm of half inhibitory concentration, I50 (m ), from the concentration–response curve for the inhibition of Ca2+-uptake. Among the compounds tested, methyl 3-(4-chlorophenyl)-4-methyl-1-[N-(4-trifluoromethylphenyl)carbamoyl]-2-pyrazoline-4-carboxylate was the most potent, the I50 value of which as 9·12×10−7 m . Variations in the activity in terms of log(1/I50) were quantitatively analysed using a substituent parameter, showing that the higher the electron-withdrawing effect of the substituent, the higher was the activity. The substituent effects were similar to those on insecticidal activity against the Americal cockroach. The higher the inhibitory activity against Ca2+ uptake, the higher seemed to be the insecticidal activity. Methyl(4S) - 3 - (4 - chlorophenyl) - 4 - methyl - 1 - [N - (4 - chlorophenyl)carbamoyl] - 2 - pyrazoline -4-carboxylate had higher inhibitory activity against Ca2+-uptake and higher in-secticidal activity than the R-isomer, but the difference was greater in theCa2+-uptake system. 相似文献
27.
In a study carried out during 2002 and 2004 in Diyarbakıir and Mardin provinces, southeast Turkey, specimens were collected
twice a month from cultivated and non-cultivated plants. Sixteen leafminer (Diptera: Agromyzidae) species were identified.
Among them,Agromyza abiens Zetterstedt, 1848;Napomyza elegans (Meigen, 1830);Phytoliriomyza dorsata (Siebke, 1864); andPhytomyza aquilonia Frey, 1964 are new records for the Turkish leafminer
http://www.phytoparasitica.org posting July 24, 2005. 相似文献
28.
A methanolic extract of Ravenia spectabilis, an isolated alkaloid, arborinine plus a fraction comprising arborinine and gamma-fagarine (VLC), showed mild to significant in vitro antibacterial activity. In a brine shrimp lethality bioassay, the extract and the fraction were found to exhibit moderate cytotoxicity having LC50 of 76.26 microg/ml and 14.98 microg/ml, respectively. 相似文献
29.
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