排序方式： 共有40条查询结果，搜索用时 265 毫秒
11.
为了分析复杂贝类和微藻中的氮杂螺环酸毒素（AZAs）及其代谢产物，建立一种基于超高效液相色谱-线性离子阱/静电场轨道阱组合式高分辨质谱（UHPLC-LTQ-Orbitrap-MS）联用技术的非定向筛查分析方法。采用Full MS/dd MS2、PRM和Target-SIM/dd MS2三种质谱鉴定模式，整合多种数据采集挖掘策略，通过研究多种AZAs在不同基质样品中的质谱裂解规律及特征碎片离子丰度，实现AZAs及其衍生物的快速筛查检测和精准鉴别。结果表明：PRM模式能有效排除AZAs同分异构体的干扰，获得更高的专属性，适用于目标代谢物筛查；应用Full MS/dd MS2和PRM结合的方式，根据AZAs裂解途径及多种AZAs代谢产物裂解规律，在贝类中共鉴别出20种AZAs系列化合物，其中包括初步推测了3种新型AZAs代谢产物的结构。应用本方法还发现AZA9、AZA10、AZA19等代谢物均随代谢过程持续升高，是AZA2在贝类代谢过程中的末端产物。该方法能够为复杂基质中的AZAs系列毒素及其衍生常规检测与精准鉴别提供参考，可应用于解析AZAs毒素在贝类体内的代谢转化机制研究。 相似文献
12.
目的：探究温阳解毒方联合隔药灸治疗糖尿病神经源性膀胱（DNB）阳虚毒郁证的临床疗效。方法：将52 例DNB阳虚毒郁证患者随机分为2组,每组各26 例。对照组予皮下注射胰岛素或口服降糖药控制血糖,治疗组在对照组基础上予温阳解毒方口服及隔药灸治疗,2组均治疗4周。比较2组治疗前和治疗2、4周后膀胱残余尿量（RUV）、中医证候积分和血糖水平［包括空腹血糖（FPG）、葡萄糖负荷后2h血糖（2hPG）］。结果：治疗组脱落1 例,对照组脱落3 例。2组治疗2周后的RUV、中医证候积分、FPG、2hPG及治疗组治疗4周后的RUV、中医证候积分与本组前一时间节点比较,差异均有统计学意义（P<0.01）;2组治疗2、4周后RUV、中医证候积分组间比较,差异均有统计学意义（P<0.05,P<0.01）,但FPG、2hPG组间比较,差异均无统计学意义（P>0.05）。2组治疗过程中均未出现明显不良反应。结论：温阳解毒方口服联合隔药灸能够有效治疗DNB阳虚毒郁证,可持续减少膀胱残余尿量,缓解临床症状。 相似文献
13.
Totally more than 500 yeast strains were isolated from seawater, sea sediments, mud of sea salterns, marine fish guts and marine algae. The results of routine and molecular biology identification methods show that nine strains among these marine yeasts belong to Aureobasidium pullulans, although the morphologies of their colonies are very different. The marine yeasts isolated from different marine environments indicate that A. pullulans is widely distributed in different environmental conditions. These Aureobasidium pullulans strains include A. pullulans 4#2, A. pullulans N13d, A. pullulans HN3-11, A. pullulans HN2-3, A. pullulans JHSc,A. pullulans HN4.7, A. pullulans HN5.3, A. pullulans HN6.2 and A. pullulans W13a. A. pullulans 4#2 could produce cellulase and single cell protein. A. pullulans N13d could produce protease, lipase, amylase and cellulase. Both A. pullulans HN3-11 and A. pullulans HN2-3 were able to produce protease, lipase and cellulase. A. pullulans JHSc could secrete cellulase and killer toxin. Both A.pullulans HN4.7 and A. pullulans HN5.3 could yield lipase and cellulase. A. pullulans W13a was able to secrete extracellular amylase and cellulase while A. pullulans HN4.7 and A. pullulans N13d could produce siderophores. This means that different A. pullulans strains from different marine environments have different physiological characteristics, which may be applied in many different biotechnological industries. 相似文献
14.
15.
采用聚丙烯酰胺凝胶电泳技术研究了8种同工酶在海蜇的刺胞和中胶层的表达特异性,利用RAPD技术对海蜇刺胞组织的DNA标记进行研究。结果表明,作为生物体防御清除自由基的SOD,在刺胞和中胶层均有表达。而与酯类化合物代谢相关的EST、维持细胞正常的能量代谢的ATPase,能在海蜇和口冠海蜇的刺胞中表达,而不能在中胶层中表达,所以,EST和ATPase可作为刺胞毒素的分子标记。碳水化合物代谢中重要的酶类MDH和ADH、清除细胞内H2O2的POD、催化磷酸单酯水解的重要酶类(与磷脂的转移、消化、吸收等活动密切相关的)ACP、在体外碱性环境下能水解有机磷脂键而产生一个有机基团和无机磷酸根的ALP,这5种酶仅在毒性较强的口冠海蜇刺胞中表达,MDH和ACP活性很高,在毒性相对较弱的海蜇刺胞中不表达。所以,这5种酶可作为海蜇毒性强弱的标记。以两种海蜇刺胞DNA为模板,S11、S32、S38、S95等4个随机引物的RAPD谱图差异明显,亦可作为毒素强弱的间接分子标记。 相似文献
16.
Dolmatova L.S. Eliseykina M.G. Timchenko N.F. Kovaleva A.L. Shitkova O.A. 《中国海洋湖沼学报》2003,21(4):293-304
Pure fraction (92% - 95%) of phagocytes (FP) and a mixture of amoebocytes (62%) and morula cells (38 % )-FPMC- of the holothurian Eupentacta fraudatrix ( Holothuroidea,Dendrochirota ) were obtained by using ficoll-verographine step gradient. Basal production of reactive oxygen species (ROS) in FP quantified by using reduction of nitroblue tetrazolium (NBT) was more than twice that in FPMC. Thermostable toxin of Yersinia pseudotuberculosis (TST) at differentconcentrations ( 0.2; 0.5; 2.5 μg/ml, but not 0.1 μg/ml) stimulated NBT reduction in FPMC after 24 h incubation. In FP, TST at concentrations of 0.1 and 0.2 μg/ml inhibited and at concentrations of 0.5 and 2.5 μg/ml stimulated NBT reduction after 24 h incubation. Maximal effect was observed in FP and FPMC at TST concentrations of 0.5 and 0.2 μg/ml, respectively. Addition of catalase (0.7 μg/ml) to the cells treated with TST (2.5 μg/ml) was followed by a decrease in NBT reduction compared to that under toxin treatment alone. TST stimulated superoxide dismutase activity in ccncentration-dependent manner (maximum at 0.5 μg/ml concentration in FP) after 24 htreatment, and this stimulation was prevented by a commercial catalase. Plant lectin concanavalin A stimulated NBT reduction more than 5-fold in FPMC compared to the control. With addition of TST, lectin stimulated ROS to lesser extent than that with lectin alone. When catalase, TST, and lectin were added into the FPMC simultaneously, ROS increase was similar to that under lectin treatment alone. On the whole, data obtained indicated that ROS generation in holothurian coelomocytes especially occurs in both stimulated and not stimulated phagocytes, and that changes in ROS production by these cells may be one of the mechanisms of antibacterial protection of holothurians. 相似文献
17.
为确定中国沿海不同地区织纹螺中的毒素成分,本研究在江苏省、浙江省和福建省设立了多个采样点,对采集的半褶织纹螺样品进行了毒性测试和毒素组成分析。研究结果显示,采集的织纹螺样品毒性范围为2—664MU(mouse unit)/g湿重,其中,采自江苏省连云港地区的织纹螺样品毒性远高于其它地区。应用高效液相色谱-质谱联用(high-performance liquid chromatography-mass spectrometry,LC-MS)方法对样品中的毒素成分进行分析,在各地的织纹螺样品中均检测到了河豚毒素(TTX)及trideoxy TTX、4-epi TTX和anhydro TTX等衍生物,但各种毒素成分所占的比例存在差异。自江苏省连云港市和浙江省舟山市采集的织纹螺样品中,Trideoxy TTX是主要的毒素成分,TTX和其它两种毒素成分次之;而自江苏省盐城市、浙江省宁波市及福建省宁德市和莆田市采集的织纹螺样品中,TTX的含量最高。采集自江苏省连云港和浙江省舟山市的大部分织纹螺样品中,肌肉组织的毒素含量最高,其次是消化腺组织,其余组织中的毒素含量最低。高毒性成分TTX的最高值主要出现在肌肉组织或消化腺组织中。从实验结果可以看出,各地的有毒织纹螺中毒素成分基本一致,而各种毒素成分所占的比例有一定的差异,织纹螺的毒性与高毒性成分TTX的含量有关。 相似文献
18.
采用基因工程的方法，进行重组质粒HF443一EGFP的构建和在哺乳动物细胞中的表达，并进行了其用于赤潮毒素检测的可能性研究。结果表明，用PCR技术扩增EGFP基因，用XbaⅠ、Hind Ⅲ双酶切并纯化，与同样双酶切并纯化的HF443质粒连接，可构建重组质粒HF443-EGFP；利用Lipofect AMINE2000转染体外培养哺乳动物BIU-87细胞。在培养体系中加入不同浓度的GTX，而后加入Na^ 通道激活剂乌头碱以诱导绿色荧光蛋白表达，荧光显微镜下观察细胞中绿色荧光蛋白表达的变化情况。细胞发出的荧光随毒素浓度的增加而减弱，存在一定的剂量效应关系，提示毒素GTX可显著影响绿色荧光蛋白的表达，重组质粒：HF443-EGFP用于赤潮霉素检测有一定的可行性. 相似文献
19.
Totally more than 500 yeast strains were isolated from seawater, sea sediments, mud of sea salterns, marine fish guts and
marine algae. The results of routine and molecular biology identification methods show that nine strains among these marine
yeasts belong to Aureobasidium pullulans, although the morphologies of their colonies are very different. The marine yeasts isolated from different marine environments
indicate that A. pullulans is widely distributed in different environmental conditions. These Aureobasidium pullulans strains include A. pullulans 4#2, A. pullulans N13d, A. pullulans HN3-11, A. pullulans HN2-3, A. pullulans JHSc, A. pullulans HN4.7, A. pullulans HN5.3, A. pullulans HN6.2 and A. pullulans W13a. A. pullulans 4#2 could produce cellulase and single cell protein. A. pullulans N13d could produce protease, lipase, amylase and cellulase. Both A. pullulans HN3-11 and A. pullulans HN2-3 were able to produce protease, lipase and cellulase. A. pullulans JHSc could secrete cellulase and killer toxin. Both A. pullulans HN4.7 and A. pullulans HN5.3 could yield lipase and cellulase. A. pullulans W13a was able to secrete extracellular amylase and cellulase while A. pullulans HN4.7 and A. pullulans N13d could produce siderophores. This means that different A. pullulans strains from different marine environments have different physiological characteristics, which may be applied in many different
biotechnological industries. 相似文献
20.
近年中国沿海普遍受到脂溶性贝类毒素(lipophilic shellfish toxins,LSTs)的污染。钦州湾是国内外闻名的牡蛎养殖基地,目前仍不了解该海域海水和主要养殖品种香港牡蛎(Crassostrea hongkongensis)沾染LSTs毒素情况与食用安全性。本文于2015年10月至2016年9月,在钦州湾香港牡蛎养殖区海水交换口处,通过固相吸附毒素跟踪技术(solid phase adsorption toxin tracking,SPATT)吸附收集海水中的脂溶性贝类毒素,同时每月采集香港牡蛎样品,应用液相色谱串联质谱法分析海水和香港牡蛎体内的LSTs毒素含量与组成,并对香港牡蛎食用安全性进行评估。结果表明:(1)海水共检出GYM、OA和PTX2三种组分,平均浓度分别为0.44、14.20和1.67μg/(kg resin·30d)。香港牡蛎共检出DTX2、GYM、SPX1、Homo-YTX四种组分,其中Homo-YTX为定性结果, DTX2、GYM、SPX1三者平均浓度分别为0.95、18.86和0.95μg/kg。(2) GYM毒素均值在海水中和香港牡蛎体内含量变化趋势呈正相关,Pearson相关系数为0.70;OAs毒素在海水中和香港牡蛎体内变化趋势类似, Pearson相关系数为0.35。(3)毒素存在一定季节变化。海水OA和PTX2夏季高,其他季节低,均值最高值分别发生在7月和6月;香港牡蛎体内GYM冬季和夏季较高,DTX2春季和夏季较高;但海水中的GYM和香港牡蛎体内的SPX1全年变化均不明显。总体而言,钦州湾海水和香港牡蛎已受到多个LSTs毒素组分污染,海水LSTs毒素含量较国内其他海域低,参考欧盟LSTs毒素标准,本海域的香港牡蛎脂溶性贝类毒素仍未超标,可放心食用。 相似文献