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101.
Functional stay-green (FSG) is characterized by delayed senescence during the reproductive stage in rice. A recombinant inbred line (RIL) population derived from ‘Pusa 677’/‘PSG16’ was used to study the genetics of FSG in a rice mutant, ‘PSG16’. The RILs exhibited significant variation under two N regimes for agro-morphological traits, leaf chlorophyll content, flowering time, yield components and nitrogen (N) use. Using a genome wide linkage map spanning 1910.8 cM with 104 polymorphic markers, we have mapped six major quantitative trait loci (QTLs). One robust QTL on chromosome 1 was associated consistently across different N regimes with chlorophyll content and flowering time. The QTL on chromosome 7 was associated with grain number, whereas the QTL on chromosome 6 was found related to N harvest index and spikelet fertility. Although ‘PSG16’ showed a clear advantage in grain yield as well as having better N assimilation, we could not establish a direct genetic relationship SG trait and N use. Based on the QTL information, FSG trait of ‘PSG16’ could be useful in deciphering multiple stress responses in rice.  相似文献   
102.
Aeromonads are ubiquitous in aquatic environments and have been implicated in fish and human infections. In this study, we isolated, studied antimicrobial susceptibility patterns and screened the existence of 15 virulence genes in aeromonads from two famously consumed fish species—seven marine Tiger Grouper (Epinephelus fuscoguttatus) and eight freshwater Marble Goby (Oxyeleotris marmoratus) from the aquaculture hatchery in Sabah, Malaysia. A total of 30 aeromonads (17 A. caviae, 9 A. rivuli, 4 A. dhakensis) were identified using PCR targeting GCAT gene, rpoD‐restriction fragment length polymorphism and multi‐locus phylogenetic analysis. All 30 strains were resistant to amoxicillin and cephalothin and five strains were multidrug‐resistant. Nine virulence genes (lip, ela, eno, fla, aerA, hylA, dam, alt and ser) present in A. dhakensis, suggesting the virulence potential of this species as a fish pathogen. This study offers as a baseline for future studies in monitoring and managing these two fish in aquaculture industry.  相似文献   
103.
The possible applications of genie male sterility (GMS) in plant breeding arc reviewed and discussed. The basic contribution of GMS is that it provides a means of genetic emasculation which can be applied for the massive production of hybrids. There are two main fields of application: (1) the production of hybrid varieties and (2) inter- and intraspecific hybridization and back-crossing programmes for the introduction of genetic variation into crop varieties. Several schemes have been proposed for using GMS in hybrid breeding in different crops. These are discussed under four headings: genetic methods, cy-togenetic methods, temporary restoration of fertility and manual pollination. The application of GMS in hybridization intended for the introduction of alien genes is discussed as well as factors affecting the pollination of genie male steriles.  相似文献   
104.
Pimobendan is a benzimidazole‐pyridazinone derivative, marketed as a racemic mixture for the management of canine heart failure. Pharmacokinetics of the enantiomers of pimobendan and its oral bioavailability have not been described in dogs. The aim of this study was to describe pharmacokinetics of three formulations of pimobendan in healthy dogs: the licensed capsule product, and novel liquid and intravenous formulations. A three‐period, nested randomized two‐treatment crossover design was used. Pimobendan was administered p.o. at 0.25 and i.v. at 0.125 mg/kg. Blood and plasma samples were analysed by liquid chromatography–mass spectrometry. Noncompartmental modelling was used to describe the pharmacokinetics. Parameters were compared between formulations using a general linear model. Bioequivalence of the oral formulations was tested using CI90 for AUC(0–∞) and Cmax. Bioavailability of pimobendan after oral dosing was 70%. Liquid and capsule formulations were bioequivalent only for AUC. The positive enantiomer of pimobendan (PE) had a larger volume of distribution than the negative enantiomer (NE) (281 ± 48 vs. 215 ± 68 mL/kg; P = 0.003) and a shorter half‐life (21.7 vs. 29.9 min; P = 0.004). The NE was distributed more quickly than the PE into blood cells. Enantiomers of pimobendan have differing absorption, distribution and elimination. The pharmacokinetics of pimobendan in healthy dogs was described.  相似文献   
105.
To systematically review the quality of evidence comparing the cardiopulmonary effects and quality of anesthesia after induction with alfaxalone vs. other anesthetic agents in dogs and cats. Studies published from 2001 until 20th May 2013 were identified with the terms ‘alfaxan’ OR ‘alfaxalone’ OR ‘alphaxalone’ in electronic databases: Discovery, PubMed, ScienceDirect, and Wiley Interscience. The study design and risk of bias of all included studies were assessed. Twenty‐two studies from 408 (22 of 408, 5.39%) satisfied the inclusion criteria. Fourteen studies (14 of 22, 64%) focused on dogs and nine (9 of 22, 40%) on cats. One study had both dogs and cats as subjects. (Hunt et al., 2013) Twelve studies were rated an LOE1, and six of these as ROB1. One, seven, and two studies were rated as LOE2, LOE3, and LOE5, respectively. In dogs, strong evidence shows that induction quality with either alfaxalone‐HPCD or propofol is smooth. Moderate evidence supports this finding in cats. In dogs, moderate evidence shows that there is no significant change in heart rate after induction with either alfaxalone‐HPCD or propofol. In cats, moderate evidence shows no significant difference in postinduction respiratory rate and heart rate between alfaxalone‐HPCD and propofol induction. Strong evidence shows dogs and cats have smooth recoveries after induction using either alfaxalone‐HPCD or propofol, before reaching sternal recumbency.  相似文献   
106.
Four MRI variables have recently been suggested to be independently associated with a diagnosis of thoracolumbar intervertebral disk extrusion or protrusion. Midline intervertebral disk herniation, and partial intervertebral disk degeneration were associated with intervertebral disk protrusion, while presence of a single intervertebral disk herniation and disk material dispersed beyond the boundaries of the intervertebral disk space were associated with intervertebral disk extrusion. The aim of this retrospective, cross‐sectional study was to determine whether using these MRI variables improves differentiation between thoracolumbar intervertebral disk extrusions and protrusions. Eighty large breed dogs with surgically confirmed thoracolumbar intervertebral disk extrusions or protrusions were included. Randomized MRI studies were presented on two occasions to six blinded observers, which were divided into three experience categories. During the first assessment, observers made a presumptive diagnosis of thoracolumbar intervertebral disk extrusion or protrusion without guidelines. During the second assessment they were asked to make a presumptive diagnosis with the aid of guidelines. Agreement was evaluated by Kappa‐statistics. Diagnostic accuracy significantly improved from 70.8 to 79.6% and interobserver agreement for making a diagnosis of intervertebral disk extrusion or intervertebral disk protrusion improved from fair (κ = 0.27) to moderate (κ = 0.41) after using the proposed guidelines. Diagnostic accuracy was significantly influenced by degree of observer experience. Intraobserver agreement for the assessed variables ranged from fair to excellent and interobserver agreement ranged from fair to moderate. The results of this study suggest that the proposed imaging guidelines can aid in differentiating thoracolumbar intervertebral disk extrusions from protrusions.  相似文献   
107.
Twelve profiles representing the principal soils of five major agricultural areas (Al-Kharj, Gassim, Hofuf, Taif and Wadi Dawasir) in Saudi Arabia were described and sampled by horizons. Laboratory analyses were then made of the samples to characterize the profiles more completely. Analyses were also made for certain nutrient elements to get some measure of their levels in the soils.The profiles are tentatively classified in the Entisol and Aridisol orders of the American taxonomy. Five Entisol profiles were considered to be Fluvents and two Psamments. Four Aridisol profiles were considered to be Argids and one an Orthid.All of the profiles are saline and calcareous and most are also sandy. Furthermore, amounts of nutrient elements such as phosphorus, iron and zinc in surface layers are below minimum levels established for similar soils in earlier investigations in other countries. Consequently, the soils are believed to lack sufficient quantities of several elements for optimum plant growth. Successful use of the soils will thus require reductions in salinity, increased levels of nutrient elements, and skillful irrigation to provide adequate moisture.  相似文献   
108.
The aflatoxin B1 degrading abilities of two different ruminants were compared in this study. One set of experiments evaluated the aflatoxin B1 degradation ability of different rumen fluid donors (steers vs. goats) as well as the rumen fluid filtration method (cheese cloth filtered vs. 0.45 µm Millipore) in a 2 × 2 factorial arrangement. Additional studies examined aflatoxin B1 degradation by collecting rumen fluid at different times (0, 3, 6, 9 and 12 h) after feeding. Cannulated Holstein steers (740 ± 10 kg bw) and Korean native goats (26 ± 3 kg bw) were fed a 60% timothy and 40% commercial diet with free access to water. Rumen fluid from Korean native goats demonstrated higher (p < 0.01) aflatoxin B1 degradability than Holstein steers. However, filtration method had no significant influence on degradability. In addition, aflatoxin degradation did not depend upon rumen fluid collection time after feeding, as no significant differences were observed. Finally, a comparison of two types of diet high in roughage found aflatoxin degradability in goats was higher with timothy hay opposed to rice straw, although individual variation existed. Thus, our findings showed the aflatoxin degradability is comparatively higher in goats compared to steers.  相似文献   
109.
肾形线虫Rotylenchulusreniformis是印度木豆的主要害虫。相传某些土著植物有杀虫功效。因此,将Argemone,Calotropis,Caster,Merigold,Mustard,Neem,Parthenium,Sarifa,Sesamum和Mahua共10种植物的碎叶按0.067hm ̄2的1000g±100g的施用量施入土壤中并于玻璃网房中播种了两个木豆品种。每钵接种250个线虫卵囊,未施碎叶组同样进行接种作为试验对照。观测了接种后45d时植物生长量和线虫总量等,发现楝叶处理组木豆生长量最大。与对照相比,10种植物碎叶处理均显著地抑制线虫卵襄的形成。  相似文献   
110.
The transmission of pathogens from infected to susceptible hosts may occur through contaminated fomites and inanimate objects. This type of transmission depends on the ability of the pathogens to survive in the environment. In this report, we describe the survivability of two avian respiratory viruses, e.g., avian metapneumovirus and avian influenza virus on 12 different porous and nonporous surfaces. The viruses survived on some of the surfaces for up to 6 days postcontamination but not after 9 days. Both viruses survived longer on nonporous surfaces than on porous ones. One of the reasons for poor survival on porous surfaces could be inefficient elution of virus from these surfaces. These results should be helpful in determining how long the premises should be left vacant after an outbreak of these viruses has occurred in poultry houses.  相似文献   
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