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对模拟空间微重力条件下大鼠T细胞发育受阻的神经免疫调节机理进行初步探究.采用流式细胞检测技术测定模拟微重力大鼠胸腺中不同发育阶段T淋巴细胞的数量变化,用ELISA法测定胸腺组织中去甲肾上腺素(NE)和内源性糖皮质激素(GC)的含量.结果表明模拟微重力模型大鼠出现明显胸腺萎缩(p<0.05),CD3+CD4+CD8-和CD3+CD4-CD8+T细胞数量明显减少(p<0.05);模拟微重力大鼠胸腺中NE和GC含量有升高的趋势.模拟微重力大鼠胸腺中发生了从双阳性T细胞向单阳性T细胞的发育阻滞,这种异常可能与神经内分泌免疫调控相关.  相似文献   

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为了分析大鼠弥漫性轴索损伤(DAI)后病理学变化及核因子-κB(NF-κB)的表达,探讨了NF-κB在弥漫性轴索损伤中的作用,构建了大鼠DAI动物模型.运用Glees-Marsland染色法和Weil氏染色法观察伤后不同时间段的病理学改变,并运用免疫组化SABC法观察NF-κB的表达.实验结果表明,大鼠弥漫性轴索损伤后1h即可观察到部分轴索肿胀、断裂,髓鞘水肿、分层等现象,24h可见典型轴索收缩球形成,髓鞘崩解呈筛网状改变,72h轴索断裂数量、范围及髓鞘筛网状改变达到高峰;伤后1h,脑组织内可见NF-κB阳性细胞,伤后3h阳性细胞数增多,伤后24h达到高峰,持续到72h,伤后7d,仍可见阳性细胞表达,但数量减少.对照组细胞核未见阳性表达.大鼠弥漫性轴索损伤后NF-κB表达增加,可能与轴索继发性损伤有关.  相似文献   

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以采前套袋控制病原菌潜伏侵染的杨梅果实为材料,采后接种橘青霉病菌,旨在研究橘青霉侵染对杨梅果实酚类物质含量及相关氧化酶活性变化的影响。结果表明:橘青霉侵染初期,杨梅果实细胞多酚氧化酶(PPO)、过氧化物酶(POD)活性呈上升趋势,酚类物质快速合成以提高自身的抗病能力。而同时期苯丙氨酸解氨酶(PAL)活性并没有相应增加,反而下降较快,致使木质素合成受阻,说明橘青霉侵染虽然诱导杨梅果实产生一定的抗病性,但这种抗病能力有限。贮藏中后期,虽然POD活性略有下降,PPO活性保持平稳,但二者始终处于较高水平,从而导致前期积累的酚类物质被大量降解,加上前期木质素合成受阻的影响,橘青霉更容易穿透杨梅果实细胞壁,进入细胞组织内繁殖生长,最终导致果实腐败。  相似文献   

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采用显微观察技术对披针新月蕨(Pronephrium penangianum)的配子体发育和卵发生进行了研究.结果表明:披针新月蕨孢子褐色,二面型,接种后约12 d,孢子萌发,经丝状体和片状体阶段,发育成原叶体,孢子萌发是书带蕨型(Vittaria-type),原叶体发育是槲蕨型(Drynaria-type),成熟原叶体是心形,接种46 d后产生颈卵器和精子器.披针新月蕨的颈卵器起源于原叶体生长点下方的原始细胞.原始细胞经过2次不等分裂,形成3个细胞,分别是顶细胞、初生细胞和基细胞.其中,初生细胞不等分裂,形成中央细胞和颈沟细胞.随后,中央细胞不等分裂形成腹沟细胞和卵细胞.随着卵细胞成熟,颈沟细胞和腹沟细胞逐渐退化,但腹沟细胞通过孔区与卵细胞相连.卵细胞成熟后,细胞上表面具有明显的卵膜,中央具有受精孔.本研究对于完善蕨类植物生殖生物学和探讨蕨类植物的演化具有重要意义.  相似文献   

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马尾松Pinus massoniana人工林广泛分布于我国南部,为了理解马尾松人工林在不同气候条件下的响应特点和分布特征,以中国广西中亚热带、南亚热带和北热带不同气候条件下马尾松人工林的幼龄林、中龄林和过熟林阶段为研究对象,比较分析不同气候条件下马尾松人工林木本植物物种组成及多样性特征。结果表明:(1)所研究的7个林分类型中,共记录到木本植物229种,隶属56科127属,随着中亚热带气候条件向北热带气候条件过渡,马尾松人工林林下热带分布物种占比增大,温带分布树种逐渐减少;(2)在幼龄林阶段,与南亚热带气候条件相比,中亚热带气候条件下马尾松人工林林下灌木层及木本群落整体的物种丰富度相对较高,在中龄林阶段和过熟林阶段,北热带气候条件下马尾松人工林林下木本群落物种丰富度和物种多样性最高,但优势种集中性较低;(3)在幼龄林阶段,南亚热带与北热带气候条件马尾松人工林林下物种差异性最大,在中龄林阶段,中亚热带与北热带气候条件马尾松人工林林下物种相似程度最高。气候条件变化对林下乔木层建群种有着明显影响,而且由于生境条件差异,不同气候条件下物种构成明显不同,在幼龄林阶段不同气候条件对林下木本群落影响最大。  相似文献   

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The relationship between the callus formation and intracellular Ca2+ at the early stage of development of graft unions inGinkgo biloba L. was investigated. On the second day after grafting, part of the undamaged living cells at the graft interface of the stock and scion in the regions of the cortex and pith began to dedifferentiate or divide. 8 d after grafting, a great number of callus cells were produced from the cortex and phloem, while callus bridges linking the stock with scion formed between the callus cells of the graft partners from the cortex. A membrane Ca2+ probe, chlortetracycline (CTC), was used to locate the intracellular Ca2+ distribution and it was found that the cortical and pith parenchyma cells were the first to show remarkably increased CTC-Ca2+ fluorescence, suggesting that the cortical and other parenchyma cells play a leading role at the early stage of development of graft unions by earlier dedifferentiation and more rapid production of callus cells.  相似文献   

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红色赤潮藻(Akashiwo sanguinea)和球形棕囊藻(Phaeocystis globosa)都是近年来在我国近岸海域频繁引发赤潮的藻类。为了探索红色赤潮藻和球形棕囊藻之间是否存在化感作用及作用方式,本研究采用不同起始密度培养红色赤潮藻与球形棕囊藻,并将前者的完整细胞培养液、无细胞滤液、藻液超声破碎液分别与球形棕囊藻进行混合培养,分析红色赤潮藻对球形棕囊藻细胞生长的影响。结果显示,在红色赤潮藻细胞起始密度保持5×105 cells/L的混合培养条件下,起始密度分别为5×105、1×106、2×106、1×107 cells/L的球形棕囊藻生长均受到明显的抑制;无论是含有红色赤潮藻完整细胞的培养液,还是其无细胞滤液或藻液超声破碎液,均对球形棕囊藻的生长具有显著抑制作用(P<0.01),抑制强度由强至弱依次为完整细胞培养液、无细胞滤液和藻液超声破碎液;相反,球形棕囊藻的存在对红色赤潮藻细胞的生长无显著影响(P>0.05)。因此,红色赤潮藻具有抑制球形棕囊藻生长...  相似文献   

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The cellular localization and specific expression of TR3 mRNA in rat testis were investigated by the method of immuno- histochemistry andin situ hybridization. It was demonstrated that orphan receptor TR3 was expressed in a significant amount in rat testis and TR3 protein and mRNA were specifically localized in germ cells, suggesting that TR3 may have an important function in regulating rat germ cell development.  相似文献   

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为阐述南非斑节对虾(Penaeus monodon)在工厂化养殖模式中肠道微生物的作用,本研究基于HE染色组织切片、高通量测序、Biolog ECO技术,探讨工厂化养殖模式中南非斑节对虾肠道组织结构形态、菌群特征及肠道微生物代谢活性。结果显示,南非斑节对虾肠道组织结构类似于凡纳滨对虾,肠壁结构薄且清晰,肠上皮细胞紧密连接,微绒毛排列整齐、致密,外层结缔组织厚,可见血窦分布。通过Operational Taxonomy Unit(OTU)数量、Chao 1、Simpson、Shannon指数呈现了南非斑节对虾肠道菌群丰富度和多样性变化,测序数据合理;肠道菌群结构中门类主要包括变形菌门Proteobacteria、浮霉菌门Planctomycetes、放线菌门Actinobacteria、疣微菌门Verrucomicrobia;目水平中含量最高的是红杆菌目Rhodobacterales,其次是浮霉菌目Planctomycetales;属水平上含量表现为unclassified鲁杰氏菌属Ruegeria玫瑰变色菌属Roseovarius等,物种热图分析呈现相同结果。通过平均吸光值(Average Well Color Development,AWCD)显示肠道微生物代谢活性总体变化趋势,24h微生物代谢活性较弱,随时间的延长,代谢活性逐渐增加,直至144h后趋于平稳。本研究分析了南非斑节对虾肠道特征,为后续研究及健康养殖提供理论依据。  相似文献   

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降香黄檀(Dalbergia odorifera)为珍稀树种,天然分布的降香黄檀濒临绝迹,为保护现有的降香黄檀种质资源,本研究以广西降香黄檀荚果作为研究对象,观察荚果和种子的生长发育变化情况,并对降香黄檀种子部分生理生化指标及发芽率的变化进行测定,探讨降香黄檀荚果和种子的生长发育规律,为确定其适宜采收期提供理论支撑。结果表明:降香黄檀荚果和种子的颜色由浅绿色逐渐过渡到黄褐色,最终在盛花期后160 d后变为深褐色;荚果和种子体积大小在整个采收期中一直维持不断增长的趋势,且在盛花期后185 d开始缓慢而稳定地增长;种子含水量在盛花期后185 d后降至35%左右并趋于稳定;种子可溶性糖含量呈现先升高后降低的趋势,在盛花期后165 d最高,为45 g·kg-1左右,直至盛花期后195 d降至42 g·kg-1左右;种子可溶性蛋白含量呈“双峰”动态变化,盛花期后135 d达到第1个峰值,盛花期后180 d达到第2个峰值,之后开始缓慢下降;种子的发芽势、发芽率在盛花期后140-170 d达到最高,且与170 d后无显著性差异。因此,盛花期后185-200...  相似文献   

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Byin situ hybridization, the localization of orphan receptor TR3 mRNA has been observed in early developmental follicles. TR3 mRNA is first expressed in the ovarian interstitial cells on day 2 after birth, and then in granulosa cells (GC) in primary follicles on day 4. The expression level of TR3 mRNA in GC increases following the follicular development. Its higher expression can be observed in the outer layer of GC and inner layer of theca cells (TC) on day 6, where the cells present active proliferation and differentiation. The expression of TR3 is in an increasing manner until the large antral follicles on day 30. The mRNA is only expressed in the healthy, but not atretic follicles in adult rat ovaries. Injection of epidermal growth factor (EGF) has dramatically enhanced its expression in the early stage of developmental follicles. It is therefore suggested that TR3 may play a role in regulating growth and differentiation of ovarian somatic cells in the early stage, and its expression is regulated by EGF.  相似文献   

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为探明广西马尾松Pinus massoniana人工林土壤碳(C)、氮(N)、磷(P)化学计量特征,揭示马尾松人工林土壤养分平衡机理及其时空动态变化,为马尾松人工林可持续经营提供理论依据,研究以广西4个典型区域马尾松人工林为对象,采用空间代替时间的方法,比较不同区域各林龄土壤有机碳(SOC)、全氮(TN)和全磷(TP)含量及其化学计量比的变化规律。结果表明:SOC、TN和C/N的变异系数较小,分别为21%、27%和22%,属弱变异,在不同林龄和区域中其值比较稳定。林龄、区域及其交互作用对SOC、TN、TP、C/P、N/P的变化均有显著影响(P<0.05)。SOC、TN含量呈波动性变化,在成熟林阶段最低;SOC含量在幼龄林阶段最高,TN含量在近熟林阶段最高。土壤TP含量在中龄林阶段最低,且随林龄增加呈先减少后增加的趋势。土壤C/N、C/P、N/P平均值均在成熟林中最高,且显著高于近熟林和过熟林(P<0.05);土壤C/P、N/P平均值随林龄增加呈先减少后增加再减少的趋势。华山地区SOC、TN和TP含量最低,而土壤C/N、C/P、N/P平均值最高。天洪岭地区土壤C/N平均值最低...  相似文献   

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为探究织锦巴非蛤(Paphia textile)幼体发育各阶段水体菌群的组成和结构特征,为其苗种规模化人工繁育提供理论依据,本研究采用高通量测序技术对幼体在D形幼虫期(HD)、壳顶期(HK)、变态前期(HB)、变态后期(HA)、稚贝期(HZ)的水体菌群进行测序分析。Alpha多样性指数结果表明,HD菌群丰度和菌群多样性均最高,而HZ菌群丰度最低,HB菌群多样性最低。在门分类水平上,幼体发育所有阶段中占优势的细菌门类主要有变形菌门(Proteobacteria)[包括α-变形菌纲(Alphaproteobacteria)和γ-变形菌纲(Gammaproteobacteria)]、拟杆菌门(Bacteroidota)和放线菌门(Actinobacteriota)。在科分类水平上,红杆菌科(Rhodobacteraceae)和黄杆菌科(Flavobacteriaceae)是整个育苗周期的主导类群;微杆菌科(Microbacteriaceae)相对丰度在HB低于1%,在HA和HZ逐渐增长,分别为9.95%和12.82%;冷形菌科(Cryomorphaceae)相对丰度在HD不足1%,在HK、H...  相似文献   

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为探讨一年两收金槐花不同时期叶片内营养物质的含量变化规律,以营养期、花芽期、花蕾期、盛花期和果期5个时期的一年两收金槐叶片为试材,对其干物质、粗纤维、粗脂肪、粗蛋白、钙和磷等含量进行测定分析。结果表明:干物质含量在第一季果期阶段含量最高(37.2%),第二季花蕾期含量最高;第一季和第二季花芽期至花蕾期的干物质含量都呈现上升趋势,说明该阶段需要消耗大量营养物质。第二季采收时各时期粗蛋白含量均低于第一季采收各时期,均在花芽期含量最高,其中第一季采收花芽期为5.99%,第二季花芽期为5.35%。第二季粗脂肪含量除了花芽和盛花期略高于第一季外,其他时期都低于第一季,第二季粗脂肪含量最高为盛花期(1.19%)。第二季采收时金槐在花芽-花蕾-盛花阶段粗纤维、灰分和钙含量明显高于第一季,第二季磷含量在营养期-花芽-花蕾阶段要低于第一季,但在盛花期到果期要显著高于第一季,其中第二季时磷含量最高为盛花期(0.126%)。第二季芦丁含量显著低于第一季,其中第二季花蕾时期芦丁含量为27.5%,但第一季花蕾时期芦丁含量却达到36.7%。因此,可在第一季采收结束及时补充磷肥,以促进二季金槐的花芽分化。  相似文献   

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Investigating the distribution of follicle stimulating hormone (FSH) and luteinizing hormone (LH) in the swimming crab, Portunus trituberculatus, helps in the understanding of its reproductive regulation mechanism. This study has detected the location of vertebrate FSH- and LH-like substances in the brain and the thoracic ganglion mass with immunocytochemical techniques. Their immunoreaction is very weak or negative during the immature period and the post-spawning period, while it is stronger in the mature period. Localization of FSH-like immunoreactive cells resembles that of LH-like cells. These immunoreactive cells were observed chiefly in the anterior median cell-duster of the protocerebrum with stronger immunostaining. There were only a few in the inboard cell-cluster of the olfactory lobe of the deutocerebrum and the posterior cell-cluster of the tritocerebrum. Immunoreactive cells were located in all the three ganglia in the thoracic ganglion mass. These results indicated that substances resembling the vertebrate FSH and LH exist in P. trituberculatus, and their expression has some correlation with the developmental stage of ovaries, thus they might engage in the ovary development and ovulation.  相似文献   

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Investigating the distribution of follicle stimulating hormone (FSH) and luteinizing hormone (LH) in the swimming crab, Portunus trituberculatus, helps in the understanding of its reproductive regulation mechanism. This study has detected the location of vertebrate FSH- and LH-like substances in the brain and the thoracic ganglion mass with immunocytochemical techniques. Their immunoreaction is very weak or negative during the immature period and the post-spawning period, while it is stronger in the mature period. Localization of FSH-like immunoreactive cells resembles that of LH-tike cells. These immunoreactive cells were observed chiefly in the anterior median cell-cluster of the protocerebrum with stronger immunostaining. There were only a few in the inboard cell-cluster of the olfactory lobe of the deutocerebrum and the posterior cell-cluster of the tritocerebrum. Immunoreactive cells were located in all the three ganglia in the thoracic ganglion mass. These results indicated that substances resembling the vertebrate FSH and LH exist in P. trituberculatus, and their expression has some correlation with the developmental stage of ovaries, thus they might engage in the ovary development and ovulation.  相似文献   

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