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1.
The morphology and organogenesis of Chinese giant salamander, Andrias davidianus, in its different developmental periods and stages are described in detail, which provides an intact criterion for distinguishing different stages of its developmental process. Based on the external morphological and internal histological features, six periods including 20 stages of organogenesis of Chinese giant salamander are established, which are cleavage period, blastula period, gastrula period, neurula period, organogenesis stage and hatching stage. Generally, the embryonic development of Chinese giant salamander is consistent with those of Eastern newt, Cynops orientalis, and Black spots frog, R. nigromaculata. However, they have some differences in the early cleavage process and the development of digestive system. The cleavage of Chinese giant salamander, A. davidianus is not a discoidal division type, which is different from other species reported. And the first three cleavages being meridional and a retardant development of its digestive system without halter and sucker existing are the evident features of the embryonic development of Chinese giant salamander.  相似文献   

2.
通过观察在全人工繁育条件下大鲵的胚胎发育及器官的形成过程,对比仿天然生态养殖的大鲵胚胎发育过程,对大鲵从受精卵到孵化为幼苗出膜进行了连续系统的形态学观察.结果发现:人工繁育的大鲵在胚胎发育至神经胚期和器官形成期,有明显的"神经沟出现"、"视泡形成"和"心脏跳动"的特征,因而在传统分期的基础上增加了"神经沟期"、"视泡形成期"和"心脏跳动期",从而将大鲵的胚胎发育过程细化为23个时期;虽然同种大鲵的人工繁育和仿生态养殖方式绝大部分发育时期的外形特征基本相同,但在卵裂期和神经胚期依旧存在差异;并利用人工繁育技术,提高其孵化率,为进一步研究大鲵的人工繁育提供理论基础和实验材料.  相似文献   

3.
Based on more exquisitely preserved specimens of Markuelia hunanensis recently recovered from Middle and Upper Cambrian in western Hunan and in the light of Synchrotron radiation X-ray tomo-graphic microscopy, the developmental sequence from cleavage through organogenesis to the pre-hatching of Cambrian embryo Markuelia, especially the developmental sequence during the pre-hatching stage, i.e. from the earliest period when the scalids and tail spines only took shape to the latest period (just about hatching), is established. This developmental sequence provides a pattern of embryonic development during the pre-hatching stage, which has not been established in the living scalidophorans (priapulids, loriciferans and kinorhynchs). Thus, it not only enriches our knowledge on the embryonic development of the extant descendants of Markuelia, but also opens a new window to the evolution and development of the animal.  相似文献   

4.
为研究铜离子暴露对中国大鲵的毒性效应,以中国大鲵幼体为研究对象,采用慢性染毒法,将大鲵幼体暴露于0mg/L、1.0mg/L、1.5mg/L和3.0mg/L的铜溶液中30d,观察铜离子胁迫下的大鲵幼体临床症。之后立即对大鲵幼体进行解剖并观察其皮肤、肝脏、胰脏和小肠组织的病理变化,同时采集大鲵幼体的皮肤、肝脏、胰脏和小肠,利用石蜡切片和HE染色对大鲵幼体的组织病理损伤进行观察。结果表明,随着铜离子浓度的增加,大鲵幼体异常行为与其体表黏液的分泌也越加频繁;铜离子胁迫会导致大鲵幼体膀胱显著膨大并充斥大量尿液;铜离子对大鲵幼体皮肤的真皮结构、肝脏和胰脏细胞会产生一定的病理损伤,但对大鲵幼体皮肤、肝脏、胰脏和小肠组织结构未造成毒害效应。本研究表明,铜离子胁迫30d后会对大鲵幼体产生一定的毒性效应,并且毒性程度与铜离子的浓度呈正相关关系。  相似文献   

5.
日本沼虾胚胎发育时期消化酶活力和氨基酸含量   总被引:1,自引:0,他引:1  
采用生物化学方法测定了日本沼虾胚胎发育过程中四种消化酶的比活力和氨基酸的含量.结果显示:卵内可溶性蛋白的含量随着胚胎的发育逐渐下降,但在原肠期的可溶性蛋白含量略高于囊胚期.四种消化酶中类胰蛋白酶、胃蛋白酶和淀粉酶活力在胚胎发育早期和后期较高,中期较低.纤维素酶活力较低且在胚胎发育过程中变化规律不明显.总氨基酸含量在胚胎发育早期下降较快,胚胎发育至后无节幼体期氨基酸含量下降幅度变缓.必需氨基酸中亮氨酸的含量高,非必需氨基酸中谷氨酸的含量最高.单个必需氨基酸含量与必需氨基酸总量的比值(A/E)在整个胚胎发育过程中的变化基本趋于一致.  相似文献   

6.
采用定时取样 ,间断观察的方法 ,对耳萝卜螺胚胎发育的形态特征进行了观察。发现耳萝卜螺的胚胎发育过程分 7个时期 :卵裂期、囊胚期、原肠期、担轮幼虫期、面盘幼虫期、幼螺形成期和孵化期。对各期的外部形态特征进行了描述 ,并绘制了各期形态图 ,记录了各期发育所经历的时间  相似文献   

7.
Zhou  Bin  Shen  ChengDe  Zheng  HongBo  Zhao  MeiXun  Sun  YanMin 《科学通报(英文版)》2009,54(12):2082-2089
There are many controversial issues in loess studies such as natural vegetation types on the Chinese Loess Plateau during the historical periods and the spatial and temporal evolution of C3/C4 plants. Elemental carbon isotopic composition (δ^13Cec) in the loess section may offer new evidence for these problems. Elemental carbon (EC) is produced by incomplete combustion of vegetation, and its carbon isotopic composition has a very small difference from that of the formal vegetation, then δ^13Cec can be used as a record to recover the changes of vegetation. Elemental carbon was extracted by applying the oxidation method from the Ioess-paleosol sequence in the central Chinese Loess Plateau, and its car- bon isotope composition was analyzed by the isotope mass spectrometer. The results showed that the vegetation in this region was a mixed type of C3 and C4 plants, dominated with C3 plants in most of the time. Since late Quaternary, C3/C4 plants may not follow a simple glacial-interglacial cycle mode on the Chinese Loess Plateau, but showing fluctuations. C3 plants increased gradually in L4 period, and more C3 plants occurred during $3 period, and C4 plants increased again during L3-- L2 periods, after that, Cs plants dominated again during S1 --S0 periods. During periods of paleosol development, C3 plants were abundant in S3 and S1, and there were more Ca plants in S2 and SO. During periods of loess sedimen- tation, there were more C3 plants in L4 and L1, and there were more C4 plants in L3 and L2. On the orbital timescale, the vegetation variations revealed by δ^13Cec record are consistent with the results of pollen data and also similar to the results obtained by organic carbon isotopic composition since the last glacial period.  相似文献   

8.
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   

9.
潘祥龙      郝二伟    **  谢金玲      杜正彩      侯小涛      邓家刚     《广西科学》2019,26(5):560-568
采用模式生物斑马鱼模型评价海洋中药厚藤水提物(Ipomoea pes-caprae(Linn.) Sweet water extract,IWE)及醇提物(Ipomoea pes-caprae(Linn.) Sweet alcohol extract,IAE)的安全性。采用受精后3 dpf (Day post fertilization) AB系斑马鱼进行急性毒性评价,将受精后10 hpf (Hours post fertilization)斑马鱼用于胚胎发育毒性及心脏毒性评价;将受精后3 dpf的gz15Tg/+(AB)肝脏荧光蛋白转基因斑马鱼用于肝脏毒性评价。结果表明,急性毒性实验中厚藤水提物半数致死浓度(LC50)为2.84 mg/mL,10%致死浓度(LC10)为1.46 mg/mL;厚藤醇提物LC50为1.32 mg/mL,LC10为0.76 mg/mL。胚胎发育毒性实验中厚藤水提物最大非致死浓度(MNLC)组及LC10组干预24 h对斑马鱼胚胎未见尾部自主运动现象且发育迟缓,斑马鱼发育至72 hpf出现心脏和软黄囊肿大现象;厚藤醇提物LC10组与空白对照组比较出现心包水肿,血瘀,观察中各组未见胚胎发育畸形现象。心脏毒性实验中空白对照组斑马鱼胚胎心跳节律规则、搏动强有力;厚藤水提物及醇提物在24 hpf,48 hpf,72 hpf时间点1/3MNLC组、MNLC组及LC10组分别与空白对照组比较,均能明显减慢斑马鱼胚胎的心率且呈现剂量依赖性(P<0.01);厚藤水提物及醇提物1/3MNLC组、MNLC组及LC10组分别与空白对照组比较,均能明显增加斑马鱼胚胎的SV-BA间距(P<0.01)。肝脏毒性实验中厚藤水提物中各给药组与空白对照组比较,肝脏荧光面积均有减少趋势,组间比较无差异性;厚藤醇提物中1/3MNLC组、MNLC组及LC10组与空白对照组比较,肝脏荧光面积均有增加趋势,但组间比较无差异性,各给药组斑马鱼的丙氨酸氨基转移酶(ALT)、天冬氨酸转氨酶(AST)水平与空白对照组比较均无显著差异。本实验中厚藤水提物的LC50显著高于醇提物。高剂量LC10组均对斑马鱼胚胎发育产生一定毒性作用。厚藤水提物及醇提物随着给药剂量增加,明显减慢斑马鱼胚胎的心率,产生一定心脏毒性作用。厚藤水提物及醇提物均未引起明显的肝脏毒性。  相似文献   

10.
探索心电噪声与睡眠分期是否存在关联.统计觉醒、浅睡、深睡、眼动睡眠及睡眠时相转换间期的心电噪声分布情况.选取循环交替模式睡眠数据库的失眠组(N=7)与正常睡眠组(N=14)的心电进行比对分析,发现噪声时段主要分布于觉醒期(失眠组84.2%±16.0%,正常组53.6%±21.9%,P<0.01)与睡眠时相转换间期(失眠组9.4%±12.7%,正常组23.6%±14.0%,P<0.05).睡眠中的心电噪声时段主要分布于觉醒期,其次分布于睡眠时相转换间期.  相似文献   

11.
目的 分析绞股蓝的研究现状,以发现其研究热点及变化趋势,为今后研究提供参考。方法 检索中国知网(CNKI)、万方、维普、中国生物医学文献数据库和Web of science中1991年1月1日至2021年12月31日绞股蓝的相关文献,采用CiteSpace.5.7.R5软件对文献作者、研究机构、关键词等内容构建知识图谱的可视化分析。结果 共筛选纳入中文文献2491篇、英文文献510篇。中、英文文献发文量总体呈波浪式上升趋势;研究机构和作者的共现知识图谱显示,研究机构和作者主要集中在各大高校和科研院所;论文发文量最多的作者分别是谭华炳和朴香兰;发文量最多的机构是吉首大学生物资源与环境科学学院和中国科学院,各研究机构间合作较少;高频关键词知识图谱显示“绞股蓝总皂苷”、“绞股蓝皂苷”、“绞股蓝多糖”关键词中心性排在前3位。中英文文献分析显示绞股蓝的研究主要集中在药理作用和临床实验等方面,成分分析、药效物质作用机制、临床应用、开发利用是今后的研究热点。结论 目前绞股蓝的研究仍处于发展阶段,科学合作网络分布松散,未来作者、研究机构之间需跨团体、跨区域增强团队间交流合作,为进一步研究提供借鉴。  相似文献   

12.
Two set ofAndrias davidanus fertilized eggs and its seedlings were got by means of artificial reproduction. The sections of the embryo ofAndrias davidianus were made by histological method. The expression of homologous sequences of Quox-1 gene has been studied by immunohistochemical method with special antibody. Results show that the expression of homologous sequences of Quox-1 gene was detected in the epidermis of blastula and gastula. The highly expression was investigated in the epidermis at the neural tube phrase and the tail bud stage. Deng Fengjiao: born in October, 1954, Associate Professor  相似文献   

13.
In wheat, plant height is an important agronomic trait, and a number of quantitative trait loci (QTLs) controlling plant height have been located. In this study, using the conditional and unconditional QTL mapping methods, combined with data from five different growth stages over two years of field trials, the developmental behavior for plant height in wheat was dissected. Nine unconditional QTLs and 8 conditional QTLs were identified, of which 6 were detected by both methods. None of the 11 QTLs was detected at all of the 5 investigated developmental stages, but 7 QTLs were detected at certain stages in both years. Further analysis identified 9 unconditional QTLs at different stages, which could explain the phenotypic variation from 4.81% to 17.35%. It was noteworthy that one major QTL designated QHt-4B-2, which was located on chromosome 4B, was detected on May 18 and 25 in both years, and its genetic contributions to plant height ranged from 13.42% to 16.13%. Moreover, of the 8 conditional QTLs identified, six were detected in both years, in the order of QHt-3BQHt-4B-1QHt-4B-2QHt-4DQHt-5A and QHt-2B expressed at the same developmental stage. The results indicate that QTL expression during plant height development is selective and in a temporal order.  相似文献   

14.
在青岛文昌鱼中首次克隆到一个RING box同源基因,对其进行了序列特征和系统进化学分析,并且研究了该基因的胚胎发育和成体表达图式。AmphiRbx1演绎的蛋白序列与已知其他无脊椎动物和脊椎动物的同源分子表现出很高的相似性。利用原位杂交和RT-PCR技术研究该基因的表达,结果显示AmphiRbx1在胚胎发育各期均有表达,特别是在卵裂期胚胎和有高速分裂细胞的组织中有很强的表达。实验结果表明,Rbx1基因在进化中相当保守,AmphiRbx1可能在细胞分裂的调节中发挥作用。  相似文献   

15.
大鲵消化道的解剖学和组织学研究   总被引:2,自引:0,他引:2  
本文报道了中国大鲵消化道各部分的形态结构、长度和组织结构,并观察了饥饿和饱食后消化道的变化,消化道各部分的差别主要在粘膜层和肌层。食道粘膜为复层柱状上皮,其中含有杯状细胞胃粘膜上皮为单层柱状上皮,肠粘膜上皮为含有杯状细胞的柱状上皮;在肠粘膜上皮下,有许多细胞隐窝。饥饿后,胃肠萎缩,粘膜层减薄、胃腺和隐窝等组织结构减少。饱食后,则胃肠上皮和胃体积增大,细胞处于旺盛的消化吸收状态。  相似文献   

16.
17.
对不同盐度胁迫10d后盐度调节至19后恢复期间褐牙鲆(Paralichthys olivaceus)幼鱼血浆生长激素(GH)、类胰岛素生长因子Ⅰ(IGF-I)、司登尼亚钙素(STC)及肌肉和肝脏中RNA/DNA比值和糖原含量变化进行实验监测.结果表明:血浆GH质量浓度在整个实验期间未出现明显差异.IGF-I质量浓度在高盐处理始终较低,只在实验结束时恢复至对照处理水平,而低盐胁迫处理的IGF-I质量浓度则在恢复期间明显高于对照处理.胁迫期间低盐处理STC质量浓度显著低于对照处理和高盐处理,但是在恢复期间恢复至对照组水平;而高盐胁迫处理则下降至显著低于其余两个处理水平.除在胁迫结束时低盐处理的肝脏RNA/DNA高于其余两个处理外,在其他时间肌肉和肝脏的RNA/DNA在不同处理间不存在显著差异.肝脏和肌肉糖原含量在所有时间上不同处理间均不存在显著差异.  相似文献   

18.
研究了不同水分条件对3种不同演化地位的蕨类植物(海金沙(Lygodium japonicum)、水蕨(Ceratopteris thalictroides)、狗脊(Woodwardia japonica))的配子体形态发育的影响.结果表明:1)随着水分的增加,海金沙、水蕨和狗脊孢子的萌发速率加快,丝状体的长度增长; 2)在缺水条件下,配子体易发育成雄性配子体,而在水分充足条件下,配子体易发育成两性配子体或雌性配子体; 3)次生假根的形态及毛状体的数量等受到水分条件的影响; 4)孢子萌发类型、配子体发育类型及成熟原叶体和毛状体的形态结构是相对稳定的性状,可作为蕨类植物分类鉴定的依据.  相似文献   

19.
目的建立七爪风的质量分析方法。方法根据2015版《中国药典》的实验方法对七爪风药材的水分、总灰分及醇浸出物进行测定。结果广西10批不同采集时间和不同地域的七爪风药材均具有相同的植物形态和药材性状,实验测定结果:水分为8.52%~11.01%,总灰分为4.54%~7.18%,酸不溶性灰分为0.59%~1.32%,浸出物为16.81%~20.95%。结论本研究的七爪风鉴别方法,可用于该药材的质量控制分析,该实验研究结果可为建立七爪风药材的质量标准提供科学依据以便更好的开发利用其药材。  相似文献   

20.
The steroidogenic acute regulatory protein (StAR) is the key regulatory protein of steroidogenesis.De novo synthesis of StAR protein is required for intramitochondrial translocation of cholesterol to the cytochrome P450 side chain cleavage enzyme which is located on the matrix side of the inner mitochondrial membrane. This is the rate-limiting step of steroid biosynthesis. Usingin situ hybridization and immunohistochemistry we studied StAR expression in various stages of the corpora luteal and its regulation by interferon-gamma (IFNγ) in the adult pseudopregnant rat. The results indicated that expression of StAR in the corpora luteal was correlated with progesteron production and IFNγ was capable of inhibiting its expression.  相似文献   

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