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1.
本研究通过体外纯培养实验研究了3种胆汁酸盐:牛磺胆酸(TCA)、胆酸(CA)和脱氧胆酸(DCA),对沃氏嗜胆菌(Bilophila wadsworthia)菌株的生长状况的影响。比浊法和活菌计数法结果表明,TCA能显著促进该菌株生长,与添加相同摩尔浓度的牛磺酸(TAU)带来的效应接近,而CA和DCA对该菌株无显著作用。通过超高效液相色谱-质谱技术分析B.wadsworthia菌株对TCA的代谢的结果显示TCA可被该菌株分解产生CA和TAU。Ca2+沉淀法对B.wadsworthia菌株产胆盐水解酶的能力进行鉴定的结果表明该菌株具有产胆盐水解酶的能力。由此推断,TCA对B.wadsworthia菌株的促进作用主要是通过其水解产生的TAU,而非CA来发挥的。  相似文献   

2.
以实验室保存的经过低温混合诱导的乳酸菌菌株Q1-4-6为研究对象,通过生长及产酸情况,研究其在低温条件下对于各种营养素的需求,以期为工业大规模生产提供数据参考。低温条件下通过研究碳源对菌株生长及产酸的影响发现,麦芽糖和乳糖对于菌株的生长及产酸有非常好的促进作用,菌株在以蔗糖为碳源的培养基中生长缓慢,而在以乳糖为碳源的培养基中生长最好。3种氮源对于菌株生长的差异不显著,以酵母膏为氮源的菌株生长略好于其他2种。不同浓度金属离子对于菌株生长有不同影响,Zn2+的促生长作用略高于Fe2+,Zn2+浓度越低,菌株生长越好,高浓度的Zn2+则对菌株生长有抑制作用。Fe2+浓度为0.5 g/L时,菌株生长最好,Fe2+浓度过高或过低对于菌株的生长都有抑制作用。根据16S rDNA序列分析结果,同时结合形态学特征、生理生化特性,将菌株鉴定为棉籽糖肠球菌(Enterococcus raffinosus)。  相似文献   

3.
玫瑰切花保鲜剂配方研究   总被引:1,自引:0,他引:1  
以蔗糖(S)、8-羟基喹啉(8-HQ)、柠檬酸(CA)为保鲜液的基本配方,分别加入CaCl2 、NaCl、Al2(SO4)3、CaCl2+KAl(SO4)2 组成四种保鲜液,进行玫瑰切花保鲜实验。对切花瓶插寿命、花径、水分平衡值、可溶性蛋白含量和还原糖含量进行分析。结果表明,各种配方保鲜液均能延长玫瑰切花的瓶插寿命、增大花径、改善切花水分代谢状况、降低切花蛋白质和还原糖的分解速度。其中,保鲜液2% S + 280 mg/L CA + 200 mg/L 8-HQ + 1% CaCl2的保鲜效果最好。  相似文献   

4.
银苗的组织培养与快速繁殖   总被引:1,自引:0,他引:1  
1 植物名称 银苗 (Stachysfloridana)又称地灵、银条菜、银根芽。2 材料类别 茎尖。3 培养条件 芽分化培养基 :( 1 )MS + 3%糖 (云南产食用白砂糖 ,下同 )。增殖培养基 :( 2 )MS +6 BA 0 .1mg·L- 1 (单位下同 ) +IBA 0 .2 +CH(酸水解酪蛋白 ) 1 5 0 + 3%糖 ;( 3) 1 /2MS +IAA 0 .2 +2 .5 %糖。生根培养基 :( 4 ) 1 /2MS +IAA 0 .2 +IBA 0 .1 + 3%糖。上述培养基均加入 0 .5 5 %纯化琼脂粉 ,pH5 .8,1 2 1~ 1 2 3℃高温灭菌 1 5min。培养室温度 1 8~ 2 8℃ ,光照时间 1 2h·d- 1 ,光照度1 5 0 0~ 2 5 0 0lx。4 生长与分…  相似文献   

5.
为探明肉桂醛对番茄幼苗耐盐性的影响,该研究以番茄‘合作903’为试验材料,探究肉桂醛(100μg·L-1)对处于100 mmol·L-1 NaCl胁迫下番茄种子萌发与幼苗生长特性的影响。在试验中设置4组处理:对照(CK,蒸馏水)、NaCl (100 mmol·L-1)、NaCl+CA(100 mmol·L-1 NaCl+100μg·L-1 CA)、CA(100μg·L-1)。结果表明:(1)在100 mmol·L-1 NaCl胁迫下,添加100μg·L-1的肉桂醛,番茄种子的发芽势和发芽率均有所提升,番茄幼苗的根长和鲜重均显著提高,说明添加肉桂醛对NaCl胁迫下番茄种子的萌发与幼苗生长均有一定缓解作用。(2)肉桂醛能够有效降低NaCl胁迫导致的番茄幼苗根尖总活性氧(reactive oxygen species, ROS)的过量累积,缓解膜脂过氧化程度从而降低细胞死亡率。综上表明,肉桂醛处理能够通过缓解幼苗的氧化...  相似文献   

6.
目的:在前期研究中选育出的氧化硫硫杆菌TT03,为了解其对各种金属离子的适应能力而进行了试验.方法:在史塔克培养基中添加规定量的各种金属离子,接种TT03后进行摇动培养,测定培养液中的产酸以代表其实际生长状况.结果:在Co<'3+>、Zn2+为100mg/L而其他微量元素为1000mg/L时没有产生抑制作用,其中有些微量元素还表现出促进作用;除pb2+、Cd2+以外,重金属在1000mg/L下普遍表现出轻微的抑制作用,对产酸没有明显影响;当pb2+、Cd2+的含量分别在10mg/L、1mg/L时,对TT03产酸没有影响.在试验的金属离子中Cd2+对TT03产酸的抑制作用最强,在浓度30mg/L时,生长产酸被完全抑制.结论:在正常土壤环境中的金属离子含量,不会对氧化硫硫杆菌TT03的生长和产酸造成致命影响.  相似文献   

7.
肿瘤标志物联合检测在乳腺癌早期诊断中的应用   总被引:1,自引:1,他引:0       下载免费PDF全文
目的:探讨肿瘤标志物癌胚抗原(CEA)、糖链抗原19-9(CA19-9)、糖链抗原15-3(CA15-3)联合检测在乳腺癌早期诊断中的应用价值。方法:检测87例乳腺癌患者,55例乳腺良性肿瘤患者和35例健康人血清中CEA、CA19-9、CA153等肿瘤标志物的水平及3种标志物不同组合对乳腺癌的阳性检出率。结果:乳腺癌患者3种肿瘤标志物显著高于正常对照组及乳腺良性肿瘤组(P<0.01)。3项标志物不同组合对不同分期乳腺癌检出的敏感性均高于单项标志物。其中CEA+CA199+CA153组合的检出敏感性较其他组合均高,特别是对早期患者检出率明显提高。结论:CEA+CA199+CA153联合检测能提高乳腺癌的早期诊断率。  相似文献   

8.
目的:观察骨桥蛋白(OPN)和癌抗原125 (CA125)联合检测在卵巢癌早期诊断中的价值.方法:采用酶联免疫吸附法(ELISA)测定32例卵巢癌患者(A组)及40例卵巢良性病变(B组)血清中ONP、CA125水平.结果:卵巢癌患者血清中OPN及CA125水平明显高于良性对照组(P<0.05);OPN、CA125检测的敏感性分别为81.3%和71.9%,OPN+CA125联合检测的敏感性为93.8%,均高于二者的单独检测;OPN、CA125检测的特异性分别为92.5%和87.5%,OPN+CA125联合检测的敏感性为95.0%,均高于二者的单项检测;OPN+CA125联合检测的阳性预测值和阴性预测值均高于二者的单项检测.结论:OPN联合CA125联合检测可提高卵巢癌的早期诊断水平.  相似文献   

9.
目的:探讨艾迪注射液联合化疗对卵巢癌患者血清人附睾蛋白4(HE4)、糖类抗原125(CA125)、糖类抗原19-9(CA19-9)、甲胎蛋白(AFP)、癌胚抗原(CEA)及T细胞亚群的影响。方法:选取我院2014年8月至2016年2月收治的78例卵巢癌患者,按照随机数表法将其分为观察组(n=39)和对照组(n=39),对照组患者给予化疗,观察组患者给予艾迪注射液联合化疗,比较两组患者的临床疗效、治疗前后血清HE4、CA125、CA19-9、AFP、CEA水平及T细胞亚群的变化。结果:治疗后,观察组的总有效率(94.87%)显著高于对照组(76.92%)(P0.05)。治疗后,两组患者血清HE4、CA125、CA19-9、AFP、CEA水平均较治疗前明显下降,且观察组显著低于对照组(P0.05)。治疗后,两组患者CD3~+、CD4~+、CD8~+较治疗前均显著降低,且观察组患者CD3~+、CD4~+、CD8~+低于对照组(P0.05)。结论:艾迪注射液联合化疗对卵巢癌治疗效果显著,能有效降低血清HE4、CA125、CA19-9、AFP、CEA水平并改善患者免疫功能。  相似文献   

10.
在3L发酵罐中分别采用不同的碱性物质作为pH调节剂,考察其对产琥珀酸放线杆菌Actinobacillus succinogenes NJ113厌氧发酵制备丁二酸的影响。结果表明:Ca2+、NH4+调节剂对菌体生长代谢有较大阻碍作用,丁二酸产量较低;采用含Na+调节剂,在发酵中后期菌体出现絮凝现象严重,且产丁二酸能力骤降;采用含Mg2+调节剂,整个发酵过程菌体代谢旺盛,发酵效果较佳。根据各碱性物质的调节能力以及对菌体生长代谢的影响,选择NaOH、Mg(OH)2和Na2CO3、Mg(OH)2分别作为混合碱组分调节pH,并对两组混合碱中各物质的质量比例进行优化。结果表明,以NaOH、Mg(OH)2混合,两者质量比为1:1时,发酵效果最好,丁二酸质量浓度高达到69.8g/L,质量收率74.5%。该种混合碱配比可有效替代碱式MgCO3调节pH,既达到高产丁二酸的目的,又可降低生物制备丁二酸的成本。  相似文献   

11.
Scirtothrips perseae Nakahara was discovered attacking avocados in California, USA, in 1996. Host plant surveys in California indicated that S. perseae has a highly restricted host range with larvae being found only on avocados, while adults were collected from 11 different plant species. As part of a management program for this pest, a “classical” biological control program was initiated and foreign exploration was conducted to delineate the home range of S. perseae, to survey for associated natural enemies and inventory other species of phytophagous thrips on avocados grown in Mexico, Guatemala, Costa Rica, the Dominican Republic, Trinidad, and Brazil. Foreign exploration efforts indicate that S. perseae occurs on avocados grown at high altitudes (>1500 m) from Uruapan in Mexico south to areas around Guatemala City in Guatemala. In Costa Rica, S. perseae is replaced by an undescribed congener as the dominant phytophagous thrips on avocados grown at high altitudes (>1300 m). No species of Scirtothrips were found on avocados in the Dominican Republic, Trinidad, or Brazil. In total, 2136 phytophagous thrips were collected and identified, representing over 47 identified species from at least 19 genera. The significance of these species records is discussed. Of collected material 4% were potential thrips biological control agents. Natural enemies were dominated by six genera of predatory thrips (Aeolothrips, Aleurodothrips, Franklinothrips, Leptothrips, Scolothrips, and Karnyothrips). One genus each of parasitoid (Ceranisus) and predatory mite (Balaustium) were found. Based on the results of our sampling techniques, prospects for the importation of thrips natural enemies for use in a “classical” biological control program in California against S. perseae are not promising.  相似文献   

12.
Komárek has recently reviewed the various species assigned to the green algal genusNeochloris Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia. Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class.  相似文献   

13.
The genusKarschia, in the earlier sense, including saprophytes and parasites on lichens, has been thought to be a non-lichenized parallel genus of the lichen genusBuellia. Modern workers included it on the one hand inBuellia, on the other hand combined it with bitunicate ascomycetes. It is now proved thatKarschia is heterogeneous and contains but superficially similar members both of the genusBuellia of theLecanorales and of typical or masked bitunicateAscomycetes. Therefore, it can not be regarded as a link betweenLecanorales andDothideales. The type species ofKarschia belongs to theDothideales.
  相似文献   

14.
15.
Systematic significance of mature embryo of bamboos   总被引:1,自引:0,他引:1  
The mature embryo of seven species belonging to five genera of Indian bamboos is described. In all these the basic pattern of embryo organisation is same: the scutellar and coleoptilar bundles are not separated by an internode, the epiblast is absent, the lower portion of the scutellum and the coleorhiza are separated by a cleft and the margins of embryonic leaves overlap. The features unique to fleshy fruited bamboos are: presence of a massive scutellum, the juxtaposition of plumule and radicle and the occurrence of a bud in the axil of the coleoptile. The fleshy fruit bearing bamboos should be classified into one group, the tribeMelocanneae. Evidence is provided to recognise additional groups in the subfamilyBambusoideae.  相似文献   

16.
The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not.  相似文献   

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19.
Since 1999, four specific weevils (Coleoptera, Curculionidae) were released in the Republic of Congo against three exotic floating water weeds: Neochetina eichhorniae Warner and N. bruchi Hustache against water hyacinth, Neohydronomus affinis Hustache against water lettuce, and Cyrtobagous salviniae Calder and Sands against water fern. Recoveries of exotic weevils were made from all 24 release sites except one, and all four species have established and spread (up to 800 km for water hyacinth weevils). Within a few years of releases, control of water fern and water lettuce was such that fishing and navigation could be resumed, while reductions of water hyacinth populations were only beginning.  相似文献   

20.
A molecular phylogeny of Hebeloma species from Europe   总被引:2,自引:1,他引:1  
In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section.  相似文献   

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