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1.
家蚕BmN细胞的微载体培养及HBeAg的高效表达   总被引:1,自引:0,他引:1  
选择微载体Cytodex3对家蚕BmN(从SilkwormBombyxmori获得的细胞系)细胞进行高密度培养,并获得成功。观察了家蚕BmN细胞在微载体Cytodex3上的贴壁分布,研究了不同接种浓度与微载体浓度时细胞的生长情况,并筛选出最佳的技术参数。在1000mL滚瓶中用微载体Gytodex3培养家蚕细胞,在合适的培养条件下(细胞接种浓度3.6×105细胞/mL、微载体浓度5g/L),5d后,细胞的终密度达到2.8×106细胞/mL,细胞增长指数为7.9。在细胞指数生长期(传代后48~60h)用载有HBeAg基因的重组病毒(rBmHBe)接种(感染量为0.4PFU/细胞),5d后,培养上清中HBeAg滴度为1∶9.6×104,是用方瓶静止培养的家蚕细胞表达量的3倍。  相似文献   

2.
产谷氨酸棒杆菌B9和T6—13的原生质体融合   总被引:2,自引:0,他引:2  
棒杆菌B9和T6—13两菌株经UV变处理得到B9—2(SmR)和T6—13—3(RifR)两菌株,以此两菌株做为出发菌株。将对数前期的培养细胞经青霉素予处理及酶解制备原生质体,用40%PEG6000为助融剂,进行原生质体融合。用间接法检出具有Sm、Rif抗性的融合子。融合频率为6.55×10-6-1.64×10-5,融合子双抗性稳定,产谷氨酸,经摇瓶实验筛选出一株产谷氨酸明显高于亲本的融合子fu36。  相似文献   

3.
体外培养大鼠星形细胞的缺糖缺氧性损伤及药物的保护   总被引:4,自引:1,他引:3  
本实验用大鼠星形细胞体外培养模型,观察了细胞在不同条件下乳酸脱氨酶(LDH)的漏出。发现当去掉葡萄糖后,细胞缺氧5和7h后LDH漏出明显增加,5b为59.7±25.3U/mg蛋白(对照组24.7±16.3,P<0.05),7h为68.3±89U/mg蛋白(对照组39.9±212,P<0.01)。用3-氧-甲基-[1- ̄3H]-D-葡萄糖摄取法测量细胞体积,结果显示缺糖缺氧5h后细胞明显肿胀,从对照组的4.1±1.2增加到8.1±3.2μl/mg蛋白(P<0.01)。丹参有效成分764-3在0.5至50μmol/L时能减少缺糖缺氧细胞LDH漏出;在50μmol/L时能减小缺糖缺氧细胞的体积。谷氨酸受体拮抗剂DNQX(6,7-dinitroquinoxaline-2,3dione)50μmol/L能减轻星形细胞肿胀和LDH漏出。  相似文献   

4.
内循环气升式生物反应器培养甘草细胞   总被引:1,自引:0,他引:1  
自行设计研制了7L,9L及25L内循环气升式生物反应器,并应用于甘草细胞的放大培养研究。在接种量为8%(W/V)通气率为0.2—0.25vvm的条件下,甘草细胞在反应器中生长迅速。其中在9L反应器中生长最好,最高生物量达16.25g/L,生长速率达0.9g/L.d,均高于摇瓶培养。培养过程中pH值、溶氧状况通过电极自动显示记录,说明设计的气升式生物反应器适合于甘草细胞的大规模培养。  相似文献   

5.
农田生态系统N、P营养平衡及其肥料效应   总被引:5,自引:1,他引:4  
9年的农田生态系统N、P营养平衡定位试验研究表明,N、P肥配合施用,实行秸秆还田,可提高土壤有机质和全N含量,使土壤速效和迟效P库容量得到补充.最后几年的P肥利用率达21.1—65.1%,N肥为49—75%.储备性施P第1年的利用率只有6.5-7.3%,而前3年之和达到24—28.5%,9年3个时段平均利用率27.9—42.8%,补偿性施P的19.5—42.9%.施P65.5kg·ha-1·yr-1时,既能满足作物对P的需求又能补充土壤速效P库容量.  相似文献   

6.
低密度和条件培养对红豆杉细胞生长的影响   总被引:1,自引:1,他引:0  
红豆杉种胚来源的细胞,在改良B5液体培养基中继代培养的临界接种密度为鲜重40g/L.低密度培养下,10-16d的条件培养液(CM)与新鲜培养液按57:43的比例混合时,能显著缩短细胞生长的延迟期,提高生长率,100L生物反应器中,按45.5%体积分数添加条件培养液,在鲜重27g/L低接种密度下培养5周,生物量增长9倍,达干重14.3g/L.对内源植物激素、精胺、维生素和氨基酸等的比较分析表明,吲哚  相似文献   

7.
应用细胞培养、3H-TdR和3H-Leucine掺入方法,观察血小板生长因子BB(Platelet-derivedGrowthFactorBB)对体外培养兔肺动脉平滑肌细胞DNA和蛋白质合成的影响。结果表明:(1)当PDGF-BB浓度为10ng/ml时,3H-TdR掺入值已较对照组显著增高(6262.5±412.9vs833.5±124.0,P<0.05);当PDGF-BB浓度为20ng/ml时,3H-Leucine掺入值亦较对照线显著增高(10212.8±638.3vs7340.3±1197.9,P<0.05)。(2)PDGF-BB浓度在5-25ng/ml范围内,3H-TdR,3H-Leucine掺入值与剂量直线相关(rDNA=0.97,rprot=0.90P<0.05)。说明PDGF-BB刺激体外培养兔肺动脉平滑肌细胞DNA和蛋白质合成。  相似文献   

8.
肌酐酰氨基水解酶是酶法分析血清肌酐浓度的关键酶。本实验室从空气中分离到能分解肌酐 的菌株 K9510、K9511和 K9512,其中K9510菌株初步分类鉴定为假单胞菌(Pseudomonas sp.)。菌株 产酶条件优化研究结果表明:菌株在底物或底物类似物的诱导下产酶;混合金属离子溶液对菌株产 酶有促进作用。菌株产肌酐酰氨基水解酶最适培养基组成为:肌酐9g、酵母提取物1.5g、麦芽汁0.9g、 NHCl0. 5g、定容 1L。适量混合金属离子溶液,用 0. 1mol  相似文献   

9.
玉蜀黍丝核菌的鉴定特征   总被引:12,自引:2,他引:10  
李华荣  兰景华 《菌物系统》1997,16(2):134-138
在研究四川省玉米纹枯病菌系时,获得23个RhizoctonizeaeVoorhees菌株,该菌菌丝形态与P.solaniKuhn相似;菌丝细胞含3个以上椭圆形细胞核,隔膜具桶孔,桶孔周围的隔膜肿体(septalswelling)与隔膜板垂直,两端不再膨大外延;菌丝生长较快,在PDA平板26℃下培养,每24小时菌落直径增长33.2~39.1mm;菌丝与苯酚相互作用后,着色较深,呈深褐色,菌核初期为白  相似文献   

10.
应用细胞培养、^3H-TdR和^3H-Leucine掺入方法,观察血小板生长因子BB对体外培养兔肺动脉平滑肌细胞DNA和蛋白质合成的影响。结果表明:(1)当PDGF-BB浓度为10ng/ml时,^3H-TdR掺入值已较对照组显著提高(6262.5±412.9vs833.5±124.0,P〈0.05);当PDGF-BB浓度为20ng/ml时,^3H-Leucine掺入值亦较对照线显著增高(10212  相似文献   

11.
何小瑞  徐文伯 《生理学报》1992,44(3):222-228
实验在麻醉大鼠上进行。用肾小管微穿刺技术观察到,脑室内注射高张盐水(icv.HS)后:(1)近曲小管末段钠残留分数从53.0±2.1%升高至66.0±2.9%(P<0.01);氯残留分数从65.4±3.4%升高至78.2±3.9%(P<0.05);钾残留分数和小管液渗透克分子浓度无显著变化。(2)远曲小管起始段钠残留分数从8.2±0.9%升高至13.6±1.8%(P<0.05);氯残留分数从5.4±0.8%升高至9.5±1.4%(P<0.05);小管液渗透克分子浓度从139.8±6.9mOsm/kg H_2O升高至181.3±15.6mOsm/kgH_2O(P<0.05);钾残留分数无显著变化。静脉注射速尿能消除icv.HS引起的尿钾增多反应,但不能消除icv.HS引起的利尿和尿钠增多反应。上述结果表明,刺激脑内渗透压感受器能抑制近曲小管中钠和氯的重吸收,并促进远曲小管及其以后部位的钠钾交换,导致尿钠排出增多和尿钾排出增多。  相似文献   

12.
A defined medium was developed for 3 strains of Pandorina morum. The strains tested required no vitamins or other organic compounds. The optimal initial pH was between 7.0 and 8.0. Various carbon sources were tested, and only glycolate and acetate appreciably stimulated growth. Mixotrophic growth in the light was stimulated by glycolate in all 3 strains, and by acetate in strains 880 and N76-6. Only strain N76-6 utilized acetate for heterotrophic growth in the dark. Thirty strains of P. morum of world-wide distribution were surveyed for mixotrophic and heterotrophic growth with acetate. All were found to fit 1 of 3 classes with respect to acetate metabolism: (1) no effect in light or dark; (2) stimulation of growth in light only; (3) stimulation of growth in light and dark.  相似文献   

13.
A defined medium (MAM) simulating acid mine drainage waters was developed which supported reproducible growth rates of three axenic strains of Euglena mutabilis Schmitz. Growth responses to various pHs and carbon sources were examined under defined culture conditions. A lab strain and two 5eld isolates, tested over pH range 1.5-9.0, grew best under acidic conditions (pH < 5.5) with highest growth rates at pH 3-4. Photoauxotrophic growth rates of all strains at pH 3 were improved significantly over unstirred batch controls by bubbling with air and even more by enrichment with 5% CO2 in air. These results confirmed inorganic carbon limitation in batch culture. Organic carbon substrates were tested as possible carbon supplements in batch culture at pH 3. None of the strains survived in the dark on any of the twenty organic sources added. In the light, the lab strain exhibited some photoheterotrophic growth potential on glucose, sucrose, ethanol, and amino acids but growth was inhibited by acetate. Field strains showed little or no growth improvement with any organic substrate addition. Under simultaneous enrichment with acetate and 5% CO2 acetate continued to be inhibitory. Simultaneous enrichment with glucose and 5% CO2 gave higher yields of the lab strain than with CO2 alone but did not enhance growth of the field strain. We conclude that E. mutabilis is an acidophilic photoauxotroph which appears unable to use organic carbon supplements for growth even under conditions of carbon limitation.  相似文献   

14.
Equisetum scirpoides Michx., propagated from a single clone, was grown in a controlled growth chamber at 24 ± 1 C under a photoperiod of 16 hr light/8 hr darkness. The apical cell of aerial vegetative shoots gives rise to derivatives (merophytes) in a helical sequence. Each newly formed merophyte divides anticlinally to form two superposed cells that are parallel to a lateral face of the apical cell. Radial longitudinal divisions then take place in the two superposed cells. Shoot tips were fixed every 2 hr for 24 hr to determine the mitotic index of the apical cell, six subjacent cells, and the remaining cells above the level of leaf initiation. Average mitotic indices for the 24-hr period were 3.9%, 3.9%, and 7.0%, respectively. The results indicate that the apical cell is quite active mitotically; there was no clear evidence of endopolyploidy in cells of the shoot apex, young leaves or in the developing cortex, based upon cytophotometric measurements of DNA content.  相似文献   

15.
Growth of Chroomonas sp. increased with light intensity (100, 1800, and 2700 μW/cm2) with a fivefold increase from the lowest to the highest intensity. Chlorophyll and phycocyanin content per cell were greater in cells grown at low light intensity, but the ratio of chlorophyll a and c did not vary appreciably. Cells grown at low light intensity had 30% more phycocyanin than cells grown at high intensities of light. The chloroplast of cells with the higher phycocyanin content had average intrathyla-koidal widths of 300 Å, whereas those cells with the lower phycocyanin content had average intrathylakoidal widths of 200 Å. This result is compatible with the hypothesis that phycocyanin is located in the intrathylakoidal space in the cryptophyte algae. Of the various energy sources tested, only glycerol was able to support limited growth tinder nonphotosynthetic conditions. Under no condition was the chloroplast reduced to an elioplast or proplastid state. Starch accumulation was greatest in cells grown in continuous while light in glycerol. Eye-spots were commonest in cells grown in darkness and interrupted every 24 hr by a few seconds of white light. It was concluded that this organism is an obligate phototroph.  相似文献   

16.
Studies were carried out on the growth of Chromatium sp. on seafood wastewater (SFWW), which under facultative conditions and light exposure produced red pigment. The strain grew and utilized organic matter in both dark and light exposure conditions, but it produced red pigment when exposed to light. The growth was repressed by aerobic condition. The red color intensity was reduced by about 32.5+/-1.5 and 70.8+/-2.8% when kept under dark and static conditions, or aerobic and light exposure conditions, respectively. The COD of SFWW and the number of cells of Chromatium sp. were also rapidly reduced by about 78.6+/-2.7 and 92.0+/-1.0%, respectively, under aerobic and light exposure condition. KNO3 and FeCl3 also reduced red color intensity and maximum removal of organic matter and red color were 30 and 4 mg/l, respectively. Aerobic conditions increased the color removal efficiency with 30 mg/l KNO3 and 4 mg/l FeCl3 treatments up to 96.5+/-1 and 98.9+/-1%, respectively.  相似文献   

17.
为提高岩藻黄素(Fucoxanthin)提取效率, 对16株海洋硅藻岩藻黄素的检测含量和实际含量进行了分析, 并以一株牟氏角刺藻(Chaetoceros muelleri)为对象, 研究了岩藻黄素与另外两种关键光合色素(即叶绿素a和β-胡萝卜素)的含量及其消长受光强和光质影响的特征。研究结果显示, 不同种或同种不同株的海洋硅藻, 在相同的培养条件、收获时期、提取方法下, 其提取率差异大, 可从不足1%到89.78%; 岩藻黄素的检出含量各异, 从0.03到5.02 mg/g。受不同光照强度[低: 50 μmol/(m2·s); 中: 100 μmol/(m2·s); 高: 200 μmol/(m2·s)和光质(红光、蓝光)]的影响, 岩藻黄素产量呈现不同特征。在低光照强度下, 单位细胞岩藻黄素的含量相对较高。在红光条件下, 岩藻黄素的产量高于蓝光。在相同光强条件下, 岩藻黄素含量随增殖周期变化; 在单色光质条件下, 几种光合色素均在生长平台期后期含量增加。岩藻黄素的含量变化与叶绿素a和β-胡萝卜素的含量及其消长关系密切。研究为筛选藻株、优化硅藻培养条件以累积岩藻黄素提供了参考。  相似文献   

18.
用生长速率测定法研究了ZnS胶体光诱导的抑菌(bacteriostasis)作用。实验结果表明,ZnS胶体在光照时能够明显地抑制大丽菊轮枝霉(VerticilliumDahliae)的生长,而在不光照时没有这一效果。其原因是ZnS胶体在光激发下能够生成大量的活性氧自由基。在本文实验条件下ZnS胶体的半致死浓度(LC50)是4.33×10-5mol/L。  相似文献   

19.
The blue-green alga Synechococcus linearis (Naeg.) Kom. was grown in P- and N-limited chemostats over a range of potentially limiting irradiances in order to determine the combined effects of light and nutrient limitation on some aspects of the composition and metabolism of this alga. Over a narrow range of low irradiances, simultaneous limitation of growth rate by light and either N or P was shown. This simultaneous limitation of growth rate by a nutrient and a physical factor can be explained by the ability of an increased supply of one to compensate in part for a decreased supply of the other. At all irradiances, the internal concentration of the limiting nutrient increased with increasing dilution rate, and the results could be fitted to the Droop relationship. With decreasing irradiance, the internal concentration of the limiting nutrient increased. There appeared to be little or no effect of light on the minimum internal concentration of P but that of N increased with decreasing light. Both chlorophyll a and biliprotein per unit particulate C increased with increasing dilution rate and decreasing irradiance. The critical N/P ratio increased with decreasing light as the N requirement of N-limited cells increased faster than did the P requirement of P-limited cells. The composition of exponentially growing cells in complete medium varied much less with light. Neither dilution rate nor irradiance during growth had a great effect on saturated rates of P or N uptake or alkaline phosphatase activity. Calculated assimilation ratios increased with light and dilution rate. The role of the flexibility of nutrient composition in adaptation to adverse conditions and the implications of the results for the use of physiological indicators of nutrient status are discussed.  相似文献   

20.
模拟阴天对南美白对虾养殖水体理化及其生长指标的影响   总被引:1,自引:0,他引:1  
为探索阴天对南美白对虾(Penaeus vannamei Boon)养殖水体理化及其生长指标的影响, 实验采用黑色遮荫网模拟阴天弱光环境对南美白对虾进行遮荫实验, 设置遮荫组与对照组各5个平行, 实验周期7周。遮荫组采用黑色遮荫网交替性遮荫, 即第1、第3、第5、第7周遮荫, 第2、第4、第6周曝光, 对照组正常养殖。结果显示: 遮荫组与对照组的pH、DO、Chl. a、 -N、NH3-N、 -N、 -N及 -P的浓度在遮荫处理下具有显著性差异(P<0.05), Chl. a、 -N及 -P的浓度具有明显的波动性, 表现为遮荫时Chl. a的浓度极显著降低(P<0.01), -N、 -P的浓度极显著升高(P<0.01); 曝光时遮荫组Chl. a的浓度较遮荫时升高, -N的浓度极显著降低(P<0.01), -P浓度的增长幅度降低, 此时遮荫组与对照组Chl. a、 -N及 -P的浓度无显著差异。 -N的浓度在实验前5周, 遮荫组高于对照组, 第6、7周对照组高于遮荫组。 -N浓度在整个实验周期中则是遮荫组高于对照组。南美白对虾生长指标结果显示: 两个组生长指标具有显著性差异。研究表明: 妨害南美白对虾生长的主要是NH3-N, 然后是 -N; 藻类可间接促进南美白对虾生长。遮荫处理抑制藻类吸收养殖水体中的有毒离子、恶化南美白对虾的生长环境并危害对虾的生存、生长。  相似文献   

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