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1.
Seed transmission of turnip yellow mosaic virus in winter turnip and winter oilseed rapes 总被引:1,自引:0,他引:1
This is the first record of seed transmission of turnip yellow mosaic virus (TYMV) in oilseed and turnip rapes. The seed transmission of TYMV in a naturally infected winter turnip rape (Brassica napus var. silvestris) cultivar Perko PVH was investigated. By ELISA 1.6%, 3.2% and 8.3% seed transmission of the virus was found in seed of plants from three localities. The proportion of infected seeds produced by artificially infected plants of winter oilseed rape (Brassica napus ssp. oleifera) and winter turnip rape cultivars was determined. The virus transmission rate, expressed as the proportion of virus-infected plants which germinated from the seed was for the oilseed rape cvs Jet Neuf 0.1%, Solida 0.4%, Silesia 0.8%, Darmor 1.2%, SL-507 0.2%, SL-509 0.0% and for the winter turnip rape cv. Perko 1.5%. ELISA cannot be used in direct tests on bulk seed lots to estimate proportion of infected seed, but must be used on germinated seedlings. 相似文献
2.
TERESA MARYAKA HALSZKA OSMÓLSKA 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1979,12(3):265-273
Supraorbital bones in Saurolophus angustirostris are described, and their presence in all hadrosaurs is suggested. Frontal-nasal and premaxillar-nasal fontanellae are distinguished in hadrosaurs; their presence is explained as connected with growth and considered to he responsible for the variability of crest structures. New data indicating the presence of a cartilaginous diverticulum nasi within the circumnarial depression in Saurobphus ongustirostris are presented. A physiological (respiratory and/or thermoregulatory) function of the nasal diverticulum is proposed. 相似文献
3.
Twenty semen samples with mass activity greater than +3 were collected from six healthy, mature Boer goat bucks. Each ejaculate was divided into four equal parts and extended at 37 degrees C in Tris, Test, Tes and Bes buffers containing egg yolk and glycerol. Semen was placed into medium size French strawsand after 2 hours of equilibration at 5 degrees C, frozen in the vapour phase and stored in liquid nitrogen for 7 days at -196 degrees C. Progressive motility, the number of live spermatozoa and glutamic oxaloacetic transaminase (GOT) release were studied after the initial extension, after equilibration and after 15 minutes and 7 days of freezing of semen. Semen samples when extended with Tris yolk glycerol showed significantly (P<0.01) higher progressive motility and live spermatozoa than when extended with the other zwitterion buffer-based extenders. The change of extenders did not influence the release of GOT at various stages of freezing of semen (P>0.05). 相似文献
4.
30 strains of xylanolytic thermophilic actinomycetes were isolated from composted grass and cattle manure and identified as members of the generaThermomonospora, Saccharomonospora, Microbispora, Streptomyces andActinomadura. Screening of these strains for extracellular xylanase indicated that strains ofSaccharomonospora andMicrobispora generally were poor xylanase producers (0.5–1.5 U/ml) whereas relatively high activities were observed in cultures ofStreptomyces andActionomadura (4–12 U/ml).A preliminary characterization of the enzymes of strains of the latter genera suggested that xylanases of all the strains ofActinomadura exhibited higher thermostabilities than those ofStreptomyces. To evaluate the potential of thermophilicActinomadura for industrial applications, xylanases of three strains were studied in more detail. The highest activity levels for xylanases were observed in cultures grown on xylan and wheat bran. The optimal pH and temperature for xylanase activities ranged from 6.0 to 7.0 and 70 to 80°C. The enzymes exhibited considerable thermostability at their optimum temperature. The half-lives at 75°C were in the range from 6.5 to 17h. Hydrolysis of xylan by extracellular xylanases yielded xylobiose, xylose and arabinose as principal products. Estimated by the amount of reducing sugars liberated the degree of hydrolysis was 55 to 65%. Complete utilization of xylan is presumably achieved by -xylosidase activities which could be shown to be largely cell-associated in the 3Actinomadura strains. 相似文献
5.
Four consecutive trials were conducted to investigate the possibility of controlling the time of ovulation in prepuberal gilts pretreated with PMS and HCG. In trial 1 it was shown that the GnRH analog Hoe 766 was superior to other compounds tested. The following trial revealed that 10 mug of that analog is the optimal dose to elicit an ovulatory response. In trial 3 it was found that the majority (73%) of gilts had started ovulating by 39 h after Hoe 766 injection. Individual gilts started ovulating up to 4 h sooner or up to more than 5 h later. Apparently the ovulatory process of an individual gilt extends over a period of 4 - 5 h. Double insemination of 9 gilts at 34 and 41 h after Hoe 766 resulted in fertilization rates and litter sizes that compared favourably with those of corresponding gilts treated with HCG. 相似文献
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Hyung W. Nam Caleb A. Grant Ashton N. Jorgensen Carrie J. Holtz‐Heppelmann Marjan Trutschl Urska Cvek 《Proteomics》2020,20(1)
Dysfunction of glutamate neurotransmission in the nucleus accumbens (NAc) has been implicated in the pathophysiology of alcohol use disorders (AUD). Neurogranin (Ng) is exclusively expressed in the brain and mediates N‐methyl‐d ‐aspartate receptor (NMDAR) hypo‐function by regulating the intracellular calcium‐calmodulin (Ca2+‐CaM) pathway. Ng null mice (Ng–/– mice) demonstrate increased alcohol drinking compared to wild‐type mice, while also showing less tolerance to the effect of alcohol. To identify the molecular mechanism related to alcohol seeking, both in vivo microdialysis and label‐free quantification proteomics comparing Ng genotype and effects of alcohol treatment on the NAc are utilized. There is significant difference in glutamate and gamma‐aminobutyric acid (GABA) neurotransmission between genotypes; however, alcohol administration normalizes both glutamate and GABA levels in the NAc. Using label‐free proteomics, 427 protein expression changes are identified against alcohol treatment in the NAc among 4347 total proteins detected. Bioinformatics analyses reveal significant molecular differences in Ng null mice in response to acute alcohol treatment. Ingenuity pathway analysis found that the AKT network is altered significantly between genotypes, which may increase the sensitivity of alcohol in Ng null mice. The pharmacoproteomics results presented here illustrate a possible molecular basis of the alcohol sensitivity through Ng signaling in the NAc. 相似文献
9.
Aging and age‐related diseases are accompanied by proteome remodeling and progressive declines in cellular machinery required to maintain protein homeostasis (proteostasis), such as autophagy, ubiquitin‐mediated degradation, and protein synthesis. While many studies have focused on capturing changes in proteostasis, the identification of proteins that evade these cellular processes has recently emerged as an approach to studying the aging proteome. With advances in proteomic technology, it is possible to monitor protein half‐lives and protein turnover at the level of individual proteins in vivo. For large‐scale studies, these technologies typically include the use of stable isotope labeling coupled with MS and comprehensive assessment of protein turnover rates. Protein turnover studies have revealed groups of highly relevant long‐lived proteins (LLPs), such as the nuclear pore complexes, extracellular matrix proteins, and protein aggregates. Here, the role of LLPs during aging and age‐related diseases and the methods used to identify and quantify their changes are reviewed. The methods available to conduct studies of protein turnover, used in combination with traditional proteomic methods, will enable the field to perform studies in a systems biology context, as changes in proteostasis may not be revealed in studies that solely measure differential protein abundances. 相似文献
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