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1.
设M是有末端奇点的n维正规代数簇,L是M上的丰富线丛,(M,L)的数字有效值为τ=uv(u、v是互素的正整数),:M→X是由(M,L)决定的nef-值态射,F是的一般纤维。通过研究τ的取值情况对(M,L)进行分类,给出了当u=n+1,n时(M,L)和(F,LF)的较完整的分类,推广了一些文献的结果。  相似文献   

2.
This study investigated the difference of nutrient composition in Caulerpa lentillifera collected from different regions.The nutrient compositions of C.lentillifera from China's Hainan and Shandong provinces were determined and compared with those from Semporna(Malaysia),Sabah(Malaysia),Petchburi(Thailand),and two other species of seaweeds(Malaysia).The results showed that the polysaccharide and protein contents of C.lentillifera from Hainan(44.82%±0.98%and 12.5%±0.70%),Shandong(43.22%±1.42%and 14.7%±0.72%),Petchburi(59.27%±2.31%and 12.49%±0.30%),and Sabah(44.02%±2.01%and 19.38%±1.48%)were higher than those of Eucheuma cottonii(26.49%±3.01%and 9.76%±1.33%)and Sargassum polycystum(33.49%±1.70%and 5.40%±0.07%),respectively.The polyunsaturated fatty acid contents in C.lentillifera from Hainan(29.98%)and Shandong(22.11%)were higher than that in Semporna(16.76%±0.27%),Sabah(9.49%),and S.polycystum(20.34%±0.43%),but lower than that in E.cottonii(51.55%±0.57%).In Caulerpa lentillifera of Hainan and Shandong provinces,the essential amino acid(EAA)/total amino acid(TAA)ratios were 35.22%and 38.78%,respectively;and the EAA/ETAA ratios were 54.36%and 63.35%,respectively.The EAA composition of C.lentillifera was close to the ideal model of Food and Agriculture Organization/World Health Organization.C.lentillifera was rich in mineral elements,including calcium((3315.85±127.55)mg(100 g)^-1 and(3728.35±92.38)mg(100 g)^-1),magnesium((6715.74±82.58)mg(100 g)^-1 and(8128.59±242.72)mg(100 g)^-1),and trace elements,including iron((510.65±5.47)mg(100 g)^-1 and(1972.97±183.35)mg(100 g)^-1),selenium((1.04±0.08)mg(100 g)^-1 and(0.83±0.15)mg(100 g)^-1),and zinc((33.90±0.13)mg(100 g)^-1 and(11.75±2.05)mg(100 g)^-1).These results showed that C.lentillifera was more nutritious than S.polycystum or E.cottonii in terms of polysaccharide,protein,and fatty acid contents.Furthermore,both C.lentillifera species collected from Hainan and Shandong provinces show more basic nutrients.Therefore,C.lentillifera has important development and application prospects.  相似文献   

3.
在水温(28±1)℃,以配合饲料及最大摄食量的条件下,研究卵形鲳鲹(Trachinotus ovatus)幼鱼[初始体重(5.77±0.45)g]在盐度10、15、20、25、30和35下的生长及能量收支。结果表明:在盐度25时,湿重、干重、蛋白质及能量指标的特定生长率均达到最大值,分别为3.21%、2.06%、4.76%和4.66%;干重、蛋白质和能量指标的摄食率也达最大,分别为20.31%、13.57%和12.21%;干重、蛋白质和能量指标的转化效率也达最大,分别为35.61%、46.60%和52.78%。可见,盐度对卵形鲳鲹幼鱼的特定生长率、摄食率、转化效率及能量收支有显著影响。盐度对吸收效率则无显著影响,蛋白质和能量的平均吸收效率分别为94.91%和92.45%;在盐度25,卵形鲳鲹幼鱼得到最佳的能量分配模式,其收支方程为:100.00C=7.30F+10.13U+29.80R+52.77G。  相似文献   

4.
罗非鱼4个选育群体遗传结构SSR分析   总被引:2,自引:0,他引:2  
采用SSR分子标记分析了吉富品系罗非鱼的两个家系(GF1和GF2)以及奥利亚罗非鱼(Fo)和奥本尼罗罗非鱼(Fn)群体的遗传结构。结果显示,扩增后等位基因数为3~8个,随引物不同而异,14对引物共扩增60个等位基因,扩增片断大小在102~267 bp之间。微卫星分析表明,奥本尼罗罗非鱼(Fn)的平均观测杂合度(0.764 3)和平均期望杂合度(0.519 6)均最高,吉富尼罗罗非鱼(GF1)平均多态信息含量(0.419 5)最高;吉富尼罗罗非鱼(GF2)平均观测杂合度(0.614 2),奥利亚罗非鱼(Fo)的平均期望观测度(0.446 6)、平均多态信息含量(0.359 2)最低;因此,吉富鱼(GF1)的遗传多样性最高,奥利亚的遗传多样性最低。Hardy-Weinberg平衡遗传偏离指数(D)奥利亚(Fo)和尼罗(Fn)(0.463 4和0.478 9)明显高于吉富的两家系(0.234 1和0.250 0)。Fo与GF2间遗传距离(0.477 0)最大;而GF1和GF2间的遗传距离(0.302 7)最小,遗传相似系数(0.607 3)最大,可推断新一代吉富罗非鱼与本地选育群体有相对较远的亲缘关系,更具杂种优势。  相似文献   

5.
Phycoerythrin (PE) is one of the most important proteins involved in light capturing during photosynthesis in red algae. Its potential biological activities had gained wide concerns. In the present study, tumor cytotoxic and hydroxyl radical assay were preformed to detect the bioactivity of recombinant PE. Recombinant plasmids pGEX-PE and pBGL were transformed into E.coli BL21 to make two recombinant strains BEX (pGEX-PE) and BGL (pBGL). PE expressing in BEX (pGEX-PE) was validated by SDS-PAGE and Western blotting analysis. SDS-PAGE analysis indicated that the PE-GST fusion protein was mostly inclusion bod- ies. Specific expression of PE was confirmed by Western blotting analysis. The recombinant E. coli BEX (pGEX-PE) cells were col- lected and sonicated. The supernatants were reserved for the tumor cytotoxic experiments. The result of tumor cytotoxic assay indi- cated that the supernatants containing PE had the activity of inhibiting the growth of Hela cells and with the increase of protein con- centration, the inhibiting rate increased from 37.31% to 63.26%, which showed significant difference from the control. Hydroxyl radical scavenging effect was tested with supernatants of BEX (pGEX-PE) and BGL (pBGL) cell lysates treated with sonication and heating. For the sonication samples, the scavenging rates of the supernatants of BEX (pGEX-PE) and BGL (pBGL) cell lysates were significantly higher than the negative control BL21(pGEX-4T) (P<0.02), and the scavenging rates increased slowly following the increase of the protein content. For the heating samples, except for the 0.2 mg mL-1 BGL (pBGL) products, the scavenging effects of the supernatants of BEX (pGEX-PE) and BGL (pBGL) cell lysates were stronger than that of negative control BL21(pGEX-4T). However, the effect intensity was not positively correlated with the increase of the protein concentration. Though a partially de- creased hydroxyl radical scavenging activity was led by heating, the biological activity was still retained and conspicuous. This re- search showed that phycoerythrin protein expressing in E. coli has the potential medical and sanitarian value.  相似文献   

6.
【目的】系统分析不同方法提取的马氏珠母贝(Pinctada martensii)外套膜胶原蛋白的理化性质及生物学功能。【方法】分别采用酸-酶法和热水法从外套膜中提取得到两种胶原蛋白(A-PSC(Pm)和HSC(Pm)),对其氨基酸组成、微观结构及热变性温度等理化特性进行比较分析。【结果】HSC(Pm)提取率高于A-PSC(Pm);HSC(Pm)中,Gly、Glu与Arg相对含量较高,分别为20.16%、17.57%和10.07%;而A-PSC(Pm)中,Glu、Asp与Arg相对含量为19.67%、11.63%和10.07%;紫外光谱和红外光谱分别显示,两种胶原蛋白均在220 nm左右有强吸收峰,且具有典型的胶原蛋白特征带(酰胺A、B、Ⅰ、Ⅱ和Ⅲ带);扫描电镜结果显示,A-PSC(Pm)呈致密多孔网状结构,HSC(Pm)则基本为薄片状;DSC分析结果表明,HSC(Pm)具有更好的热稳定性。【结论】酸-酶法及热水法提取的胶原蛋白均具有类V型胶原蛋白特性,其结构特征及其理化性质均存在差异,可根据需求选择特定的胶原蛋白提取方法用以开发不同类型的产品。  相似文献   

7.
研究波吉卵囊藻及藻―菌体系对创伤弧菌(Vibrio vulnificus)、副溶血弧菌(Vibrio parahaemolyticus)和溶藻弧菌(Vibrio alginolyticus)生长的影响,结果显示:无菌波吉卵囊藻对创伤弧菌、副溶血弧菌的生长均有显著促进作用(P<0.05),对溶藻弧菌的生长无显著影响(P>0.05);波吉卵囊藻―沼泽红假单胞菌体系对溶藻弧菌有明显抑制作用(P<0.05);无菌波吉卵囊藻―枯草芽孢杆菌体系对溶藻弧菌的生长有显著促进作用(P<0.05),对创伤弧菌、副溶血弧菌的生长无显著影响(P>0.05);带菌波吉卵囊藻对三株弧菌均有明显抑制作用(P<0.05);带菌波吉卵囊藻共栖细菌对三株弧菌均无明显抑制作用(P>0.05);在无菌波吉卵囊藻中回加带菌藻共栖细菌,分析实验10~18d的数据发现的数据发现藻―菌体系对创伤弧菌、副溶血弧菌的生长有显著影响(P<0.05),藻―菌体系逐渐恢复对三株弧菌的抑制作用。  相似文献   

8.
人为热一定程度上影响着城市的局地环境和微气候.以2016年中国地级市为研究对象,首先采用了能源消耗清单法结合Suomi-NPP (National Polar-orbiting Partnership)VIIRS (Visible Infrared Imaging Radiometer Suite)夜间灯光数据的方法估...  相似文献   

9.
1-methladenine (1-MA) induces starfish oocytes maturation via surface reaction followed by the appearance of a cytoplasmic maturation factor which in turn induces germinal vesicle breakdown (GVBD) to resume meiosis. Cellular mechanisms involved in GVBD were investigated by microinjection of metabolic inhibitors. Colchicine (Co) inhibited maturation, cytochalasin-B (CB) delayed GVBD and actinomycin-D-(Act-D) and puromycin (Pu) had no effect. It appears that the microtubule and the microfilament systems are associated with the nuclear membrane dissolution during the process of oocyte maturation of starfish.  相似文献   

10.
The changes of taxonomical composition of the Late Jurassic-Early Cretaceous palynofloras are revealed,in the upper stream of Bureya River in Bureya Basin.The palynofloras are dominated as follows:the Berriasian one by ferns(Cyatheaceae,Dicksoniaceae,Osmundaceae),Classopollis and bisaccate pollen;the Valanginian-Hauterivian one by ferns(Cyatheaceae,Dicksoniaceae),Ginkgocycadophytus and bisaccate pollen;the Barremian one by ferns(Cyatheaceae,Dicksoniaceae);the Aptian one by ferns(Cyatheaceae,Dicksoniaceae,Gleicheniaceae) and Ginkgocycadophytus;and the Albian one by ferns(Schizaeaceae) and bisaccate pollen.In the Albian the floral diversity raises with the angiosperms appearing.  相似文献   

11.
研究了4种Hg2+浓度对细基江蓠果孢子和四分孢子附着、萌发和生长的影响。结果表明:与对照组相比,Hg2+抑制了果孢子附着却促进了四分孢子的附着,但0.0025 mg/L浓度与对照组的差异不显著(P>0.05),各浓度间差异显著(P<0.05);Hg2+在实验浓度范围内(0.0025、0.0050、0.0075、0.0100 mg/L)影响了孢子的正常萌发,使孢子不能正常分裂和生长,刺激了孢子脱落,并且使盘状体的形态发生变异;`Hg2+不同浓度之间也存在显著差异(P<0.05),并且Hg2+浓度越高对孢子的萌发和生长影响越大。  相似文献   

12.
在室内水泥池,利用沙层自净养殖模式和直接铺沙养殖模式对不同规格的方斑东风螺(Babylonia areolataLink)进行了高密度养殖的研究。结果表明,沙层自净养殖模式养殖小螺、中螺、大螺组日均增重分别为0.031、0.088、0.098 g/d,沙层NH4+-N最高含量w分别为1.3、2.1、3.1 mg/L,H2S最高含量w分别为0.03、0.07、0.14mg/L,各规格组东风螺保持正常生长和活动,成活率92.9%以上;直接铺沙养殖模式养殖小螺、中螺、大螺日均增重分别为:0.023、0.051、0.068 g/d,成活率分别为95.2%、86.7%、84.9%,沙层NH4+-N最高含量w达到13.7mg/L,H2S最高含量w达到0.47 mg/L,沙层底质恶化,东风螺活动异常、不摄食。可见,沙层自净养殖模式对方斑东风螺的生长、成活率、沙层水质控制效果显著,在一定程度上克服了直接铺沙养殖底质恶化问题。  相似文献   

13.
The effect of light intensity ( 1500 Ix and 5000 Ix) on the total lipid and fatty acid composition of six strains of marine diatoms Cylindrotheca fusiformis (B211 ), Phaeodactylum tricornutum (Bl14, Bl18 and B221) Nitzschia closterium (B222) and Chaetoceros gracilis (B13) was investigated.The total lipids of B13, Bl14, and B211 grown at 5000 Ix were lower than those grown at 1500 Ix. No evident changes were observed in Bl18, B221 and B222. Fatty acid composition changed considerably at different light intensity although no consistent correlation between the relative proportion of a single FA and light intensity. The major fatty acids of the 6 strains were 14:0, 16:0, 16:l(n- 7) and 20:5(n-3) . Cylindrothecafusiformis had high percentage of 20:4n - 6 (9.2 - 10.9% ) . The total polyunsaturated fatty acid /rl all 6 strains decreased with increasing light intensity. The percentage of the highly unsaturated fatty acid eicosapentaenoic acid (EPA) decreased with increasing light intensity in all strains except Chaetoceros gracilis.  相似文献   

14.
【目的】探究马氏珠母贝(Pinctada fucata martensii)对干露胁迫的响应,为马氏珠母贝健康养殖和遗传育种提供基础资料。【方法】在不同温度下对马氏珠母贝进行干露胁迫,探究温度对马氏珠母贝干露耐受的影响;筛选出马氏珠母贝干露胁迫敏感组和耐受组,比较两组的免疫相关基因表达量和植核后休养期存活率。【结果】(1)22~34℃条件下,马氏珠母贝干露耐受能力随温度升高及干露时间延长而降低;(2)22℃下,S组和T组的脯氨酸羟化酶(PHD)、葡萄糖转运蛋白(GLUT)、髓样分化因子(MYD88)、热休克蛋白(Hsp70、Hsp20)和凋亡抑制因子(cIAP)6个基因在干露过程中表达量基本呈上升趋势,组间差异显著(P<0.05);(3)植核试验结果表明耐受组植核后休养期的存活率显著高于敏感组(P<0.05)。【结论】马氏珠母贝在高温环境下干露耐受能力降低,在适温条件下耐受组比敏感组表现出较高的存活率。  相似文献   

15.
The changes of taxonomical composition of the Late Jurassic-Early Cretaceous palynofloras are revealed,in the upper stream of Bureya River in Bureya Basin.The palynofloras are dominated as follows:the Berriasian one by ferns (Cyatheaceae,Dicksoniaceae,Osmundaceae), Classopollis and bisaccate pollen;the Valanginian-Hauterivian one by ferns (Cyatheaceae,Dicksoniaceae), Ginkgocycadophytus and bisaccate pollen;the Barremian one by ferns(Cyatheaceae,Dieksoniaceae);the Aptian one by ferns(Cyatheaceae,Dieksoniaceae,Gleicheniaceae)and Ginkgocycadophytus;and the Albian one by ferns(Schizaeaceae)and bisaccate pollen.In the Albian the floral diversity raises with the angiosperms appearing.  相似文献   

16.
抗菌肽对凡纳滨对虾生长和机体免疫的影响   总被引:1,自引:0,他引:1  
基础饲料(对照组)中添加10g/kg抗菌肽制剂喂养体重0.10±0.01g、体长2.17±0.11cm的凡纳滨对虾(Penaeus vannamei)30d,进行10d的水浴攻毒(鳗弧菌10~8/mL),探讨饲料中添加抗菌肽对凡纳滨虾生长、成活率、免疫保护率,以及肌肉中溶菌酶活性、超氧化物歧化酶活性、总抗氧化能力的影响。结果表明:饲料中添加抗菌肽可显著提高凡纳滨对虾相对增重率、成活率和对致病菌的免疫保护率(P<0.05),但对饲料系数无显著影响(P>0.05);未受外界微生物刺激时,饲料中添加抗菌肽对凡纳滨对虾总抗氧化能力有促进作用(P<0.05),受外界微生物刺激后,饲料中添加抗菌肽喂养凡纳滨对虾可提高对虾超氧化物歧化酶活性(P<0.05)和总抗氧化能力(P<0.01)。因此饲料中添加抗菌肽喂养凡纳滨对虾可提高其机体非特异性免疫。  相似文献   

17.
灰色预测模型在高层建筑物沉降预测中的应用研究   总被引:21,自引:2,他引:19  
详细讨论了一阶一元灰色预测模型GM(1,1)的基本内容及建模过程,并成功地将GM(1,1)模型应用于高层建筑物沉降监测的预测预报,相应地编写了基于MATLAB的灰色系统沉降预测程序,便于实际应用。实践证明,灰色预测模型GM(1,1)在沉降预测中具有较高的应用价值。  相似文献   

18.
The changes of taxonomical composition of the Late Jurassic- Early Cretaceous palynofloras are revealed, in the upper stream of Bureya River in Bureya Basin. The palynofloras are dominated as follows: the Berriasian one by ferns (Cyatheaceae, Dicksoniaceae, Osmundaceae), Classopollis and bisaccate pollen; the Valanginiar-Hauterivian one by ferns (Cyatheaceae, Dicksoniaceae), Ginkgocycadophytus and bisaccate pollen; the Barremian one by ferns (Cyatheaceae, Dicksoniaceae); the Aptian one by ferns (Cyatheaceae, Dicksoniaceae, Gleicheniaceae) and Ginkgocycadophytus; and the Albian one by ferns (Schizaeaceae) and bisaccate pollen. In the Albian the floral diversity raises with the angiosperms appearing.  相似文献   

19.
从GenBank上选取40对尼罗罗非鱼(Oreochromis niloticus)的微卫星引物,分别在奥利亚罗非鱼(Oreo-chromis aureus)(83系)、红色奥利亚罗非鱼、奥利亚罗非鱼(02系)和尼罗罗非鱼的基因组上进行扩增。40对引物中有37对(92.5%)可进行有效扩增,32对引物(80%)可检测到个体间等位基因的多态性。其中引物UNH168与奥利亚罗非鱼的性别相关,在雌性个体中可扩增出二条大小不同的特异带(分别为135和171 bp),在雄性个体中则只有一条(171 bp)。将特异条带回收、克隆并测序,结果显示雌雄个体中171 bp条带的序列完全相同,包括103bp的侧翼序列和34个CA重复,在雌性个体中获得的135 bp条带则只有16个CA重复。引物UNH846、UNH860和UNH995可鉴别奥利亚罗非鱼和尼罗罗非鱼,UNH890可鉴别出红色奥利亚罗非鱼。可见,大部分的尼罗罗非鱼微卫星位点存在于奥利亚罗非鱼中。  相似文献   

20.
The prime function of the Philippine National Collection of Microorganisms (PNCM), being the national repository of microbial strains, is to collect and preserve strains for their continued viability and availability for future use. To date, a total of 2144 strains of bacteria (1357), yeasts (250), filamentous, fungi (377), algae (14), and strains still to be identified (146) are maintained at the PNCM. These are preserved and maintained using various methods which include modified liquid drying (lyophilization), ultra-low temperature (−70°C) storage in 10% glycerol, storage in sterile soil, distilled water and overlaying with mineral oil. Periodic viability testing is done to assess the stability of these preserved cultures under storage. Aside from preservation and maintenance of cultures, the PNCM is also involved in several research activities. One of these is the isolation, characterization and identification of some Vibrio isolates from the Philippines. Details on this particular study is presented in this report.  相似文献   

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