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1.
按照常规技术进行马氏珠母贝插核育珠,在手术后第1、3、7、15、20、30和60天解剖剪取珍珠囊,利用H E染色等组织化学方法研究马氏珠母贝珍珠囊形成过程中的组织学和组织化学变化。结果表明:珍珠囊表皮细胞来自于移植细胞小片的表皮细胞;在水温27℃条件下,插核后1~3 d来自育珠贝的游走细胞逐渐将细胞小片包围;插核后7~15 d,珠核表面密集来自育珠贝的游走细胞;插核后15~20 d,细胞小片外表皮细胞增殖形成珍珠囊,珍珠囊表皮细胞和细胞核均呈扁平状;插核后20~30 d,扁平状珍珠囊表皮细胞逐渐转变为高柱型,并分泌形成透明的壳皮层物质;在插核后第60天,已形成具有分泌珍珠质功能的扁平状珍珠囊表皮细胞,细胞核呈椭圆形或近圆形。  相似文献   

2.
利用透射电镜观察九孔鲍(Haliotidaediversicoloraquatilis)的外套膜表皮细胞,结果表明细胞可分为4大类,即普通柱状表皮细胞、嗜碱性粒细胞、嗜酸性粒细胞和感觉细胞。它们在不同区域的分布、形态和数量变化与外套膜的功能分化密切相关。  相似文献   

3.
4.
The morphological characteristics and the cuttlebone formation of Sepia esculenta exposed to different water temperature fluctuations were investigated under laboratory conditions. Temperature fluctuation cycles (15 cycles, 60 d in total) consisted of the following three regimes of 4 d duration: keeping water temperature in 26°C for 3 d (Group A), 2 d (Group B), 0 d (Group C, control); then keeping water temperature in 16°C for the next 1, 2, 4 d. No significant difference in the survival rate was observed between the control and temperature fluctuation groups (P>0.05). Lamellar depositions in a temperature fluctuation cycle were 2.45±0.02 for Group A, 2.00±0.02 for Group B, and 1.78±0.02 for Group C (P<0.05). The relationship between age and number of lamellas in the cuttlebone of S. esculenta under each water temperature fluctuation could be described as the linear model and the number of lamellas in the cuttlebone did not correspond to actual age. Group A had the highest cuttlebone growth index (CGI), the lowest locular index (LI), and inter-streak distances comparing with those of control group. However, the number of lamellas and LI or CGI showed a quadratic relationship for each temperature fluctuation group. In addition, temperature fluctuations caused the breakage of cuttlebone dark rings, which was considered a thermal mark. The position of the breakage in the dark rings was random. This thermal mark can be used as supplementary information for marking and releasing techniques.  相似文献   

5.
The venerid clam (Mactra veneriformis Reeve 1854) is one of the main cultured bivalve species in intertidal and shallow subtidal ecosystems along the west coast of Korea. To understand the effects of ocean acidification on the early life stages of Korean clams, we investigated shell growth and abnormality rates and types in the D-shaped, umbonate veliger, and pediveliger stages of the venerid clam M. veneriformis during exposure to elevated seawater pCO2. In particular, we examined abnormal types of larval shell morphology categorized as shell deformations, shell distortions, and shell fissures. Specimens were incubated in seawater equilibrated with bubbled CO2-enriched air at (400±25)×10-6 (ambient control), (800±25)×10-6 (high pCO2), or (1 200±28)×10-6 (extremely high pCO2), the atmospheric CO2 concentrations predicted for the years 2014, 2084, and 2154 (70-year intervals; two human generations), respectively, in the Representative Concentration Pathway (RCP) 8.5 scenario. The mean shell lengths of larvae were significantly decreased in the high and extremely high pCO2 groups compared with the ambient control groups. Furthermore, under high and extremely high pCO2 conditions, the cultures exhibited significantly increased abundances of abnormal larvae and increased severity of abnormalities compared with the ambient control. In the umbonate veliger stage of the experimental larvae, the most common abnormalities were shell deformations, distortions, and fissures; on the other hand, convex hinges and mantle protuberances were absent. These results suggest that elevated CO2 exerts an additional burden on the health of M. veneriformis larvae by impairing early development.  相似文献   

6.
The bivalve Ruditapes philippinarum is not only one of the main mollusc species in the west Pacific Ocean, but also one of the main species for aquaculture in China. Knowledge of growth of the R. philippinarum shell will improve our understanding of the shell as an environmental archive. It is also useful for the aquaculture of R. philippinarum. In this research, a hanging box culture method was introduced in the culture of R. philippinarum. The bivalves were cultured for 126 days, from March 31 to August 3, 2002. The average growth rates of shell width, height, and thickness were 0.069, 0.046, and 0.032 mm/d, respectively. The mean increase of average individual wet mass was 0.028 g/d. The largest growth rates of both shell and average individual wet mass occurred in June, indicating that water temperature and bivalve reproduction were 2 important factors. The shell morphology underwent significant changes with shell growth. The ratio of height to thickness (value of B/C) shifted 1.58 in the first 60 days to 1.54 in the last 30 days, which was resulted from the change in major shell growth direction. Periodic changes in the B/C ratio led to corrugated shell form, which could be used to determine the age of the shell.  相似文献   

7.
Siberian larch (Larix sibirica Ledeb.) forests cover the largest areas in the Eurasian boreal zone, but there are insufficient data on its root system including the structure and functional traits of ectomycorrhizas (EM). The aim of this research is to find out if the morphological parameters of Larix sibirica EMs responded to the changes in elevation and main ecological factors (soil humidity, soil richness, soil acidity and habitat illumination). Using light microscopy, we studied EM diameter, root diameter, mantle width, and mantle volume share, share of tannin cells layers, EM density and EM length of Larix sibirica in two main types of plant communities along the elevation gradient at the Northern and Subpolar Urals. Differences in the environment were traced using phytoindication approach and the Ellenberg ecological scales. All the studied traits depend on the elevation and studied ecological factors. The diversity of fungal mantles is low, and the proportion of unstructured and pseudoparenchymatous mantles is high in response to the deterioration of the humidity, soil nitrogen content and acidity at higher-altitude habitats. Results of EM quantitative parameters measurements confirmed this pattern. We found a decline in the EM linear dimensions accompanied by a compensatory growth of the EM density with the raised elevation and the deterioration of environmental conditions.  相似文献   

8.
企鹅珍珠贝附壳珍珠的培育   总被引:1,自引:1,他引:1  
以7种聚乙烯塑料核型为珠核,正常壳形与二壳隆起的畸形企鹅珍珠贝为手术贝,培育附壳珍珠。养殖6个月,结果表明:壳形正常的育珠贝成活率为73.3%~93.8%,成珠率55.0%~82.0%;畸形贝成活率为60%,成珠率53.3%。统计分析表明:珠核高度是影响育珠贝成活率和成珠率的主要因素,珠核越高,育珠贝成活率和成珠率越低。畸形贝与正常壳形贝成活率和成珠率存在极显著差异(P<0.01),畸形贝不宜用作手术贝。  相似文献   

9.
为筛选能在马氏珠母贝外套膜边缘膜与中央膜区域稳定表达的内参基因,应用荧光定量PCR 技术,对3-磷酸脱氢酶(GAPDH)、β-肌动蛋白(β-actin)、胆色素原脱氨酶(PBGD)、微管蛋白(TUB)、TATA 盒结合蛋白(TBP)、磷脂酶A2(PLA-2)、葡萄糖苷酶(GUSB)、18S 核糖体rRNA(18SrRNA)等8 个常用的内参基因在马氏珠母贝外套膜边缘膜与中央膜区域的表达情况进行分析,并利用geNorm、NormFinder、BestKeeper 及RefFinder 软件对8 个内参基因的表达稳定性进行分析.结果表明:8 个内参基因均可获得特异性扩增产物,但稳定性各异, 其在外套膜边缘膜和中央膜区的表达稳定性顺序依次为PBGD/TBP〉TUB〉GUSB〉18SrRNA〉PLA-2〉GAPDH〉 β-actin;在荧光定量PCR 中,PBGD 和TBP 在马氏珠母贝外套膜边缘膜和中央膜区的表达比较稳定,为研究贝壳矿化机制中理想的内参基因.  相似文献   

10.
The morphology and structure of the olfactory organ of Cynoglossus semilaevis Günther are described. The oval olfactory sacs on both sides differ in size and in the number of lamellae, with those on the abocular side having smaller sacs and fewer lamellae than those on the ocular side. On the ocular side, the average ratio of sac length to eye diameter is 2.1 (i.e.>1) with an average of 91 lamellae, while on the abocular side, the values were 1.7 (i.e.>1) and 69, respectively. In addition, the surface morphology varies in different parts of the lamella. The frontal part, near the anterior nostril, is a non-sensory margin with cilia-free epidermal cells. Within this is an internal ciliated sensory area, which is intercalated with ciliated receptor cells and a few ciliated non-sensory cells. Additionally, some dense ciliated non-sensory cells make up a non-sensory area, which also contains cilia-free epidermal cells distributed in patches. In the rear of the olfactory sac near the posterior nostril, the lamellae differ in morphology from those of the frontal olfactory sac but are similar in having few ciliated receptor cells. In other words, the surface of the lamellae in the rear part of the olfactory sac is mainly non-sensory. At present, four types of lamellae (I, II, III and IV) have been recognized in relation to the pattern of the sensory epithelium. In this study, the frontal and rear lamellae resembled types I and IV, respectively, but are referred to as types I′ and IV′ because they are slightly less developed. Data on the ratio of length of lamellae to eye diameter, number of lamellae and the type of surface pattern of the lamellae show that the development of the olfactory system of C. semilaevis facilitates prey capture.  相似文献   

11.
采用垂直板聚丙烯酰胺凝胶电泳对有棘和无棘两种不同表型的栉江珧(Atrina pectinta)的外套膜组织进行了EST 和SOD 同工酶比较研究。结果显示这两种类型的酶谱表达有一定差异,但同时也存在中间类型,表明有棘和无棘的表型差异,尚不能提供它们应划分为两个种的充足证据  相似文献   

12.
We evaluated the effect of pH on larval development in larval Pacific oyster(Crassostrea gigas) and blood cockle(Arca inflata Reeve).The larvae were reared at pH 8.2(control),7.9,7.6,or 7.3beginning 30 min or 24 h post fertilization.Exposure to lower pH during early embryonic development inhibited larval shell formation in both species.Compared with the control,larvae took longer to reach the D-veliger stage when reared under pH 7.6 and 7.3.Exposure to lower pH immediately after fertilization resulted in significantly delayed shell formation in the Pacific oyster larvae at pH 7.3 and blood cockle larvae at pH 7.6 and 7.3.However,when exposure was delayed until 24 h post fertilization,shell formation was only inhibited in blood cockle larvae reared at pH 7.3.Thus,the early embryonic stages were more sensitive to acidified conditions.Our results suggest that ocean acidification will have an adverse effect on embryonic development in bivalves.Although the effects appear subtle,they may accumulate and lead to subsequent issues during later larval development.  相似文献   

13.
采用非平衡量子统计方法讨论了地幔矿物声子热传导的3种不同情况,得到了较为普遍的结果,结果表明在下地幔声子热传导将是主要机制.  相似文献   

14.
秦岭群形成于早元古宙华北南缘裂谷化环境中。其下部有一套岩浆岩建造,包括基性和酸性的火山岩或侵入岩。地球化学资料表明,基性岩具有OIB型和CNB型两种地球化学型式,酸性岩具有壳幔混合型地球化学型式。这些变化起因于不同的源区和岩石成因过程,但本质上取决于岩石圈拉张程度和地幔流能量。  相似文献   

15.
埠上金矿位于胶东金岭金矿田中北部,该文拟通过对区内典型矿石详细的岩石学、矿物学、地球化学研究,并结合大地构造学特征进行综合研究,试图揭示该矿床的矿床成因。通过详细的地球化学研究发现:该区矿石为受气液作用而成的含较多硅质矿物、金属矿物的变质岩;是由受较多岩浆的气液流体交代作用而成的;该区金矿形成于造山期,来源于洋壳俯冲带析出的流体交代原始地幔形成的EM1型富集地幔岩浆区,是EM1型富集地幔基性岩浆析出的气液流体交代壳源物质而成的产物。  相似文献   

16.
Thirty-nine isozymes in four tissues (mantle muscle, buccal bulb muscle, eye and liver) of Sepia esculenta were screened for enzymatic analysis using starch gel electrophoretic technique. Eighteen enzymes (G3PDH, LDH, MDH, MEP, IDHP, PGDH, GRS, NP, AAT, CK, AK, EST, ALP, ACP, FBP, MPI, GPI and PGM) show strong activities and good convergence in zymogram. They are proved to be suitable genetic markers in Sepia esculenta. Among the tissues used, mantle muscle is the best for electrophoretic analysis of isozymes. Eye and liver are fairly good for some special enzymes, such as LDH, EST, MPI, etc. Twenty-six loci are detected. The proportion of polymorphic loci is 0.115 in the Qingdao sample and 0.153 in the Rizhao sample (P<0.99). The mean values of the observed and expected heterozygosity per locus of Qingdao sample are 0.016 and 0.017, while those of the Rizhao sample are 0.023 and 0.025 respectively.  相似文献   

17.
The shell color of Pacific oyster (Crassostrea gigas) is a desirable trait; but the nutritional studies on C. gigas with different shell colors have not been conducted. Through successive selective breeding, five shell color strains of black (B), purple (P), orange (O), golden (G) and white (W) C. gigas have been developed. The aim of this study was to evaluate the chemical composition and nutritional value of five shell color strains and one commercial population with a common color. The biochemical composition including moisture, total protein, glycogen, ash, total fat, fatty acids (FA), amino acids and minerals was detected. The results indicated that the protein (50.76%–56.57%) was the major component. The content of glycogen showed a significant difference between orange shell and golden shell strains, as well as between commercial population and golden shell strain. In addition, all shell color strains contained a large amount of essential amino acids (12.20–14.15 g (100 g)?1), of them leucine (2.81–3.29 g (100 g)?1) and lysine (2.79–3.28 g (100 g)?1) were predominant. The oysters were rich in polyunsaturated fatty acids (42.26%–45.24% of total fatty acid) with high levels of DHA (18.53%–21.16% of total fatty acid) and EPA (17.23%–18.68% of total fatty acid). Significant differences of mineral contents (Mg, Zn, Fe and Cu) were identified among the six populations. These results indicated that C. gigas with different shell colors presented rich nutritional value with high protein, glycogen, essential amino acids and polyunsaturated fatty acids. The biochemical composition obtained in this study is useful for selective breeding of C. gigas with different shell colors.  相似文献   

18.
沿浙江诸暨石角、陈察分布的前寒武纪超基性岩分别为绍兴一江山对接带古洋壳下覆含水地促残留作和华夏古地体原始地侵高温底辟侵入体。两地超基性岩结构构造的独特性,与所处古地质构造单元之间推覆超法的运动学性质有关。岩体在地质特征和宕石化学、矿物化学等的明显差异,以及由此引致的特殊的成因条件,是分划两个不同古地质构造单元的依据:石角、陈蔡超基性岩体,应分别属于不同威尔逊旋回,同一俯冲阶段的前寒武纪上地幔深部成因的侵入岩。  相似文献   

19.
Three wild populations of Meretrix meretrix sampled from Dongxing, Beihai, and Shankou along the coast of Guangxi, China, were investigated with morphometry and karyometry. Six morphological indices (shell length, shell height, shell width, hinge length, total wet weight and shell weight) were measured. Differences in all morphological indices except hinge length were significant among the three populations (P 〈 0.05). The mean values of these indices (except for the hinge length) in the Dongxing population were larger than those in the Beihai and Shankou populations, although the latter had the largest hinge length. The karyotype of the Beihai, Shankou and Dongxing samples had ten metacentric, six submetacentric, and three subtelocentric chromosome pairs. No significant difference was shown in the centromeric index values of the chromosomes in the populations (P〉0.05). However, the order of metacentric, submetacentric and subtelocentric chromosome pairs was variable among the three populations. The results indicate a high level of inter-population variation in morphology and karyotype.  相似文献   

20.
水晶屯金矿位于我国重要的金矿集中区——河北省张宣(张家口—宣化)幔枝构造区南部,是张宣地区比较有代表性的中型金矿,张宣幔枝构造演化过程中形成的一系列多期次、多阶段的褶皱和断裂构造体系对该矿的形成和演化起着重要的控制作用。该文以幔枝构造理论为指导,在总结前人资料基础上,通过野外调查,室内综合分析,认为其外围及深部仍具有较大找矿潜力。  相似文献   

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