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31.
超级稻是巴马县近年来主推的重要水稻品系之一。由于其生长旺盛,在生育中后期长势浓郁,稻秆基部易遭受纹枯病的侵染危害。对该县甲篆乡等乡镇超级稻纹枯病的发生进行调查,分析其发病的主要原因,并提出有效的防治对策,以供稻田生产参考。 相似文献
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天然标准橡胶加工的锤磨搓揉、除杂是天然橡胶生产中的关键环节。锤磨机广泛应用于大型天然橡胶初加工生产线,其锤磨搓揉、造粒除杂效果是转盘锤磨机的重要指标,直接影响绉片等后序工艺的加工质量。研发的转盘锤磨机提高了胶块搓揉、造粒、除杂效果及改善了生产工艺,同时也提高了产品质量和产量。 相似文献
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大麦杂种优势利用研究,Ⅲ.大麦异棱型和同棱型F1杂种的杂种优势特征 总被引:1,自引:0,他引:1
研究了大麦4种杂交类型(含二棱×二棱、二棱×六棱、六棱×二棱和六棱×六棱)的F1杂种的性状表现和优势特征,比较了同棱型相配组(二棱×二棱和六棱×六棱)和异棱型相配组(二棱×六棱和六棱×二棱)的超高亲优势(Hh)组合数及其出现率。研究性状包括株高、穗长、穗下节间长、穗数、粒数、粒重、籽粒产量、籽粒蛋白质含量和赖氨酸含量等13个.结果表明,(1)二棱×二棱杂种的穗长较长、每株穗数较多、千粒重较高;六棱×六棱杂种的每穗粒数、每株粒数较多、籽粒产量较高;而异棱型相配杂种则比同棱型相配组有较高的株高、穗下节间长和千粒重。(2)4种杂交类型杂种的类型内杂种间变异,在大多数性状上均为同质,仅有株高、穗长和主穗粒数在六棱×六棱杂种中变异增大,有较大的选择潜力。(3)在13个数量性状中,有9个性状的Hh优势出现率与杂交类型显著关联;株高、穗下节间长和千粒重的Hh优势出现率在二棱×六棱和/或六棱×二棱杂种中最高,而主穗粒数、每穗粒数、每株粒数、每粒重和每株干重的Hh优势出现率则在六棱×六棱和/或六棱×二棱杂种中最高。(4)异棱型相配组杂种的株高、穗下节间长和千粒重的Hh优势率显著高于同棱型相配组杂种,依次为20/30对8/33、30/30对18/33和22/30对5/33;但同棱型相配组杂种籽粒产量的Hh优势率显著高于异棱型相配组杂种,为10/33对2/30。说明异棱型杂种易产生生物量和千粒重优势,而同棱型杂种易产生籽粒产量优势。 相似文献
36.
Taesik Yun Yoonhoi Koo Sanggu Kim Wonguk Lee Hakhyun Kim Dongwoo Chang Soochong Kim Mhan-Pyo Yang Byeong-Teck Kang 《The Veterinary quarterly》2021,41(1):163
An 8-year-old neutered male Yorkshire Terrier dog presented with head pressing, vestibular ataxia, neck tenderness, and no oculocephalic reflex. A demarcated lesion in the pons was identified on MRI. The patient was tentatively diagnosed with a glioma and was treated with hydroxyurea plus imatinib and prednisolone. After 30 days of therapeutic treatment, the patient showed a clear improvement in neurological signs, which lasted for 1117 days. On day 569 after the initiation of treatment, 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) was performed with no significant findings on visual analysis. The average and maximal standardized uptake values (SUVs) were 1.92 and 2.29, respectively. The tumor-to-normal-tissue (T/N) ratio was 0.97. The first evidence of clinical deterioration was noticed on day 1147. On day 1155, 3,4-dihydroxy-6-[18F]-fluoro-l-phenylalanine (18F-FDOPA)-PET was performed. High uptake of 18F-FDOPA was observed in the intracranial lesion. The mean and maximal SUVs of the tumor were 1.59 and 2.29, respectively. The T/N ratio was 2.22. The patient was euthanized on day 1155 and histopathologic evaluations confirmed glioma (astrocytoma). This case shows that chemotherapy with hydroxyurea plus imatinib may be considered in the treatment of canine glioma. Furthermore, this is the first case describing the application of 18F-FDG and 18F-FDOPA in a dog with glioma. 相似文献
37.
Pantu Kumar Roy Ahmad Yar Qamar Xun Fang Ghangyong Kim Seonggyu Bang Mahanama De Zoysa Sang Tae Shin Jongki Cho 《Reproduction in domestic animals》2021,56(2):342-350
Oxidative stress is inevitable as it is derived from the handling, culturing, inherent metabolic activities and medium supplementation of embryos. This study was performed to investigate the protective effect of chitosan nanoparticles (CNPs) on oxidative damage in porcine oocytes. For this purpose, cumulus–oocyte complexes (COCs) derived from porcine slaughterhouse ovaries were exposed to different concentrations of CNPs (0, 10, 25 and 50 µg/ml) during in vitro maturation (IVM). Oocytes treated with 25 µg/ml CNPs showed significantly higher levels of GSH, along with a significant reduction in ROS levels compared to control, CNPs10 and CNPs50 groups. In parthenogenetic embryo production, the maturation rate was significantly higher in the CNPs25 group than that in the control and all other treated groups. In addition, when compared to the CNPs50 and control groups, CNPs25-treated oocytes showed significantly higher cleavage and blastocyst development rates. The highest concentration of CNPs reduced the total cell number and ratio of ICM: TE cells in parthenogenetic embryos, suggesting that there is a threshold where benefits are lost if exceeded. In cloned embryos, the CNPs25 group, as compared to all other treated groups, showed significantly higher maturation and cleavage rates. Furthermore, the blastocyst development rate in the CNPs25-treated group was significantly higher than that in the CNPs50-treated group, as was the total cell number. Moreover, we found that cloned embryos derived from the CNPs25-treated group showed significantly higher expression levels of Pou5f1, Dppa2, and Ndp52il genes, compared with those of the control and other treated groups. Our results demonstrated that 25 µg/ml CNPs treatment during IVM improves the developmental competence of porcine oocytes by reducing oxidative stress. 相似文献
38.
Dae Young Kim Michael M. Zinn Solomon O. Odemuyiwa William J. Mitchell Jr. Gayle C. Johnson 《Journal of veterinary diagnostic investigation》2021,33(1):167
Canine distemper virus (CDV) has long been recognized as a cause of myocarditis; however, cases of myocarditis caused by naturally acquired CDV infection have been reported only rarely in dogs. We describe here our retrospective study of naturally acquired systemic CDV infection in 4 dogs, 4–7 wk old, that had myocarditis, with myocardial necrosis and fibrosis. One of the 4 dogs had intracytoplasmic eosinophilic inclusion bodies in cardiomyocytes. Other lesions included bronchointerstitial pneumonia (4 of 4), necrotizing hepatitis (2 of 4), splenic lymphoid necrosis (2 of 4), encephalitis (1 of 3; brain was not submitted in 1 case), and necrotizing gastroenteritis (1 of 4). The presence of CDV in the heart was confirmed by immunohistochemistry in all 4 dogs. 相似文献
39.
Hyunju Cho Yejin Kim Saebyel Hong Hojung Choi 《Journal of veterinary science (Suw?n-si, Korea)》2021,22(1)
BackgroundDiseases related to cerebrospinal fluid flow, such as hydrocephalus, syringomyelia, and Chiari malformation, are often found in small dogs. Although studies in human medicine have revealed a correlation with cerebrospinal fluid flow in these diseases by magnetic resonance imaging, there is little information and no standard data for normal dogs.ObjectivesThe purpose of this study was to obtain cerebrospinal fluid flow velocity data from the cerebral aqueduct and subarachnoid space at the foramen magnum in healthy beagle dogs.MethodsSix healthy beagle dogs were used in this experimental study. The dogs underwent phase-contrast and time-spatial labeling inversion pulse magnetic resonance imaging. Flow rate variations in the cerebrospinal fluid were observed using sagittal time-spatial labeling inversion pulse images. The pattern and velocity of cerebrospinal fluid flow were assessed using phase-contrast magnetic resonance imaging within the subarachnoid space at the foramen magnum level and the cerebral aqueduct.ResultsIn the ventral aspect of the subarachnoid space and cerebral aqueduct, the cerebrospinal fluid was characterized by a bidirectional flow throughout the cardiac cycle. The mean ± SD peak velocities through the ventral and dorsal aspects of the subarachnoid space and the cerebral aqueduct were 1.39 ± 0.13, 0.32 ± 0.12, and 0.76 ± 0.43 cm/s, respectively.ConclusionsNoninvasive visualization of cerebrospinal fluid flow movement with magnetic resonance imaging was feasible, and a reference dataset of cerebrospinal fluid flow peak velocities was obtained through the cervical subarachnoid space and cerebral aqueduct in healthy dogs. 相似文献
40.
A-Tai Truong Sedat Sevin Seonmi Kim Mi-Sun Yoo Yun Sang Cho Byoungsu Yoon 《Journal of veterinary science (Suw?n-si, Korea)》2021,22(3)
BackgroundThe microsporidian parasite Nosema ceranae is a global problem in honeybee populations and is known to cause winter mortality. A sensitive and rapid tool for stable quantitative detection is necessary to establish further research related to the diagnosis, prevention, and treatment of this pathogen.ObjectivesThe present study aimed to develop a quantitative method that incorporates ultra-rapid real-time quantitative polymerase chain reaction (UR-qPCR) for the rapid enumeration of N. ceranae in infected bees.MethodsA procedure for UR-qPCR detection of N. ceranae was developed, and the advantages of molecular detection were evaluated in comparison with microscopic enumeration.ResultsUR-qPCR was more sensitive than microscopic enumeration for detecting two copies of N. ceranae DNA and 24 spores per bee. Meanwhile, the limit of detection by microscopy was 2.40 × 104 spores/bee, and the stable detection level was ≥ 2.40 × 105 spores/bee. The results of N. ceranae calculations from the infected honeybees and purified spores by UR-qPCR showed that the DNA copy number was approximately 8-fold higher than the spore count. Additionally, honeybees infected with N. ceranae with 2.74 × 104 copies of N. ceranae DNA were incapable of detection by microscopy. The results of quantitative analysis using UR-qPCR were accomplished within 20 min.ConclusionsUR-qPCR is expected to be the most rapid molecular method for Nosema detection and has been developed for diagnosing nosemosis at low levels of infection. 相似文献