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71.
发展茶产业可带动地区提质增效和增加农户收益,为乡村振兴提供有力支撑.三江侗族自治县利用生态优势,加强标准化基地建设,培育荼产业龙头企业,出台激励政策,促进产品销售,创建核心品牌,加强人才培养等推进荼产业高质量发展,取得了一定成效.三江侗族自治县发展茶产业主要经验包括加强组织领导、加强资金保障、引领绿色发展、提高产业品质、完善配套设施.为进一步促进三江侗族自治县茶产业高质量发展,全面推进乡村振兴,应提升产业品质、打造区域公用品牌、加强一二三产融合发展.  相似文献   
72.
Betanodaviruses are the causative agents of viral nervous necrosis (VNN), a serious disease of cultured marine fish worldwide. Virus-like particles (VLPs) are one of the good novel vaccine candidates to control this disease. Until now, betanodavirus vaccine studies mainly focused on the humoral immune response and mortality after virus challenge. However, little is known about the activation of genes responsible for cellular and innate immunity by vaccines. In the present study, VLPs of orange-spotted grouper nervous necrosis virus (OGNNV) were produced in prokaryotes and their ability to enter Asian sea bass cells was the same as native virus, suggesting that they possess a similar structure to OGNNV. VLPs immunogenicity was then determined by intramuscularly vaccinating Epinephelus coioides at different concentrations (1.5 or 15 μg g?1 fish body weight, FBW) and immunizing frequencies (administration once, twice and thrice). A single vaccination with the dosage of 1.5 μg g?1 FBW is enough to provoke high titer antibodies (average 3 fold higher than that of negative control) with strong neutralizing antibody titer as early as 1 week post immunization. Furthermore, quantitative PCR analysis revealed that eleven genes associated with humoral, cellular and innate immunities were up-regulated in the liver, spleen and head kidney at 12 h post immunization, correlating with the early antibody response. In conclusion, we demonstrated that VLP vaccination induced humoral immune responses and activated genes associated with cellular and innate immunity against betanodavirus infection in orange-spotted grouper.  相似文献   
73.
从文心兰生长特点、生活环境、品种选择出发,结合海南地区实际情况,对文心兰切花栽培技术进行综述,重点总结了文心兰切花生产中的栽培基质、水肥管理、病虫害防治技术,并对如何提高文心兰切花产量提出可行性对策。  相似文献   
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A 4‐year‐old German shorthaired pointer presented with collapse and hematochezia. Radiographs showed gas and fluid‐distended small intestines and loss of serosal detail. Ultrasound examination showed hypomotile, fluid‐distended small intestines, and thrombosed jejunal veins. Multiphasic contrast‐enhanced computed tomography was performed and showed a CT “whirl sign,” an important but nonspecific sign of intestinal volvulus in human patients. At surgery, the majority of the small intestine was entangled in the volvulus and showed black discoloration. The patient was euthanized. Postmortem evaluation yielded a diagnosis of jejunoileal mesenteric volvulus secondary to a congenital omphalomesenteric duct remnant.  相似文献   
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中国对虾往西北内陆咸水水域移植的生产性试养研究   总被引:8,自引:1,他引:8  
王慧  田荣庆 《海洋渔业》1997,19(1):9-12
本文介绍了通过采用引进河水、压碱降盐等改良水质的技术措施,使中国对虾首次成功地移植到内陆咸水水域。经过1个月的试养,中国对虾平均体长增长3.82 cm,平均体重为1.82 g。  相似文献   
78.
ABSTRACT:   A total of 110 adult individuals from four ommastrephid (family Ommastrephidae) squid species ( Ommastrephes bartramii, Sthenoteuthis oualaniensis, Eucleoteuthis luminosa, and Hyaloteuthis pelagica ) were used to obtain diagnostic DNA markers for species identification. Restriction fragment length polymorphism (RFLP) analysis of a partial segment (855 bp) of the mitochondrial DNA cytochrome oxidase I (COI) gene amplified by polymerase chain reaction (PCR) revealed that the restriction profiles of two endonucleases ( Alu  I and Tsp 509 I) were diagnostic for species identification. The restriction assay partially supplemented with nucleotide sequence analysis successfully assigned 69 damaged and morphologically equivocal ommastrephid paralarvae collected in northern Hawaiian waters, identifying 60 O. bartramii , eight S. oualaniensis , and one E. luminosa . The family Ommastrephidae appears to be monophyletic. Although the phylogenetic relationships among genera were not resolved well due to apparent homoplasy and large genetic divergence between species, COI sequence data without transitions provided support for subfamily level relationships.  相似文献   
79.
pH值和Ca~(2+)浓度对日本沼虾生长和能量收支的影响   总被引:19,自引:2,他引:19  
本文报道了不同pH值(6.5、7.5和8.5)和不同Ca2+浓度(38.8.61.1和78.8ppm)对日本沼虾生长和能量收支的影响。实验结果表明,pH值对该虾的生长有一定的影响,Ca2+和pH值在影响其生长的过程中可能有一定的交互作用。pH值和Ca2+对该虾生长的影响主要是通过影响其能量摄入量实现的。本实验条件下,该虾摄入的能量平均有15.8%用于生长,1.8%作为粪便排出体外,其余用于呼吸和排泄。  相似文献   
80.
In this study, new marine ningalin B analogues containing a piperazine or a benzoloxy group at ring C have been synthesized and evaluated on their P-gp modulating activity in human breast cancer and leukemia cell lines. Their structure-activity relationship was preliminarily studied. Compounds 19 and 20 are potent P-gp inhibitors. These two synthetic analogues of permethyl ningalin B may be potentially used as effective modulators of P-gp-mediated drug resistance in cancer cells.  相似文献   
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