共查询到20条相似文献，搜索用时 15 毫秒
1.
【目的】探讨CpGDNA对生长抑素DNA疫苗免疫小鼠免疫效果的影响。【方法】生长抑素质粒pES/2SS分别与CpG-ODN、pE-CpG、细菌DNA、脂质体配合免疫小鼠，疫苗剂量为20μg/只，佐剂等量混合，2周后加强免疫。【结果】雌性小鼠免疫后4、6周，疫苗组平均增重显著高于对照组(P<0.05)。CpGDNA和DNA疫苗联合免疫后SS抗体P/N值、IgG2a/IgG1、脾细胞活性、GH和IGF-I均比单一使用DNA疫苗的高(P<0.05)。免疫后4周，P/N值以pES/2SS + CpGODN组最高，SI值以pES/2SS+ CpG-ODN组最高。CpGDNA佐剂组GH从第2周开始升高，至第6周达高峰，显著高于pES/2SS组（P<0.01），CpG-ODN组GH高水平持续时间最长，至免疫后8周，仍显著高于pES/2SS组（P<0.01）。CpGDNA组IGF-I值显著高于pES/2SS疫苗组（P<0.05）。【结论】生长抑素基因免疫小鼠可以产生SS抗体，而含CpGDNA序列的核酸佐剂及脂质体粗品，可以增强生长抑素基因疫苗的效果。 相似文献
2.
XUE Chun-lin MAO Da-gan YANG Li-guo CHENG Bao 《中国农业科学(英文版)》2007,6(7):882-889
To study the immune effect of CpGDNA on somatostatin （SS） DNA vaccine, the 20-day-old experimental mice were immunized with 20 lag SS eukaryotic expression plasmid pES/2SS with different adjuvants in equal dose, such as the synthetic CpG-ODN, the pE-CpG plasmid, E. coli DNA and the crude liposome. A booster was given two weeks later. The results showed that the body weight gain of female mice in the SS immunized group was higher than that of the control （P 〈0.05）. The levels of antibodies against SS, IgG2a/IgG1, spleen lymphocyte proliferation activity and the concentrations of GH and IGF-Ⅰ in the DNA vaccine groups combined with CpGDNA were significantly increased compared to that of the group immunized with DNA vaccine alone. All these suggested the recombinant SS expression plasmid can stimulate animals to produce antibodies against SS, and CpGDNA adjuvant can enhance the immune effect of DNA vaccine against SS and influence the concentration of GH and IGF-Ⅰ . 相似文献
3.
Peptidergic-noradrenergic interactions were examined in explants of rat sympathetic superior cervical ganglia and in cultures of dissociated cells. The putative peptide transmitters substance P and somatostatin each increased the activity of the catecholamine-synthesizing enzyme tyrosine hydroxylase after 1 week of exposure in culture. Maximal increases occurred at 10(-7) molar for each peptide, and either increasing or decreasing the concentration reduced the effects. Similar increases in tyrosine hydroxylase were produced by a metabolically stable agonist of substance P, while a substance P antagonist prevented the effects of the agonist. The data suggest that the increased tyrosine hydroxylase activity was mediated by peptide interaction with specific substance P receptors and that peptides may modulate sympathetic catecholaminergic function. 相似文献
4.
三种高渗溶液对蛙坐骨神经干动作电位的幅值及速度的影响 总被引：2，自引：1，他引：2
目的:观察葡萄糖、甘露醇、山梨醇3种高渗溶液对蛙坐骨神经干复合动作电位的幅度及传导速度的影响。方法:用青蛙制备蛙坐骨神经-胫腓神经标本,随机分为3组,每组再分为2~3个小组,即:(1)葡萄糖组(下分3个浓度小组:质量分数为10%葡萄糖组、20%葡萄糖组和40%葡萄糖组);(2)甘露醇组(下分2个浓度小组:质量分数为10%甘露醇组和20%甘露醇组);(3)山梨醇组(下分3个浓度小组:质量分数为10%山梨醇组,20%山梨醇组和40%山梨醇组)。另外设1个对照组(即任氏液组)。用M edL ab生物信号采集处理系统引导神经干复合双相动作电位,分别测定神经干双相动作电位的幅度和传导速度。结果:与对照组比较,20%、40%葡萄糖组,20%甘露醇组和20%、40%山梨醇组的动作电位幅度有显著降低,传导速度有显著减慢,呈时间依赖关系;10%葡萄糖组、10%甘露醇组和10%山梨醇组高渗溶液均可使蛙坐骨神经干动作电位幅值有不同程度上升,传导速度略微减慢。结论:20%、40%葡萄糖、20%甘露醇和20%、40%山梨醇均可降低蛙坐骨神经干复合动作电位幅值,减慢传导速度。而10%葡萄糖、10%甘露醇和10%山梨醇,则引起动作电位幅值升高。 相似文献
5.
Somatostatin receptors in rat brain, pituitary, and pancreas were labeled with two radioiodinated analogs of somatostatins 14 and 28. Two cyclic analogs of somatostatin, SMS201-995 and cyclo(Ala-Cys-Phe-D-Trp-Lys-Thr-Cys), showed biphasic displacement of binding to somatostatin receptors by these radioligands. In contrast, all other somatostatin analogs, including somatostatin-14, competed for the receptor sites with monophasic displacement of radioligand receptor binding. Thus two types of somatostatin receptors were identified. It was found that the pituitary and pancreas have predominantly one type of somatostatin receptor whereas the brain has both, and that different regions of the brain have various proportions of the two types. These findings suggest methods to characterize other types of somatostatin receptors subserving somatostatin's diverse physiological functions, including a potential role in cognitive function and extrapyramidal motor system control. 相似文献
6.
低浓度醚菊酯对鲤鱼生长及生理生化指标影响的研究 总被引：1，自引：0，他引：1
研究了鲤鱼在不同低浓度醚菊酯(48 h LC50的1 10、1 20、1 40、1 80分别设为试验1,2,3,4组)的长期(60d)暴露试验中,其行为、生长和血液生理生化指标所受到的不同影响。结果表明: 1 80、1 40、1 20 组鲤鱼的生长受到的影响不显著,1 10 组鲤鱼的生长在20 d后受到的影响显著;1 20、1 10 组鲤鱼的行为和摄食受到一定的影响,后期很少摄食,游动缓慢;1 10组鲤鱼生理生化指标受到的影响极显著,1 20、1 40组随着染毒时间的延长影响效果也逐渐显著,1 80组影响不显著。中毒鱼血红蛋白Hb量和红细胞RBC数量减少,表现出贫血;血清中谷草转氨酸ALT、谷丙转氨酸AST活性升高;Na+浓度降低,表现为高血钾和低血钠症;高浓度试验组鲤鱼血液生化指标的变化与对照组间存在着显著(P<0 05)或极显著的差异(P<0 01); 浓度组1 10 和1 20 在试验结束时死亡率各为25%和15%. 相似文献
7.
Gonadotroph-specific expression of metallothionein fusion genes in pituitaries of transgenic mice 总被引：4，自引：0，他引：4
M J Low R M Lechan R E Hammer R L Brinster J F Habener G Mandel R H Goodman 《Science (New York, N.Y.)》1986,231(4741):1002-1004
Transgenic mice expressing a metallothionein-somatostatin fusion gene contain high concentrations of somatostatin in the anterior pituitary gland, a tissue that does not normally produce somatostatin. Immunoreactive somatostatin within the anterior pituitaries was found exclusively within gonadotrophs. Similarly, a metallothionein-human growth-hormone fusion gene was also expressed selectively in gonadotrophs. It is proposed that sequences common to the two fusion genes are responsible for the gonadotroph-specific expression. 相似文献
8.
Depolarization- and ionophore-induced release of octacosa somatostatin from stalk median eminence synaptosomes 总被引：1，自引：0，他引：1
Species of somatostatin of higher molecular weight were present in the nerve terminals (synaptosomes) of ovine stalk median eminences and were released by depolarizing stimuli. One of these species was identified as the biologically active molecule octacosa somatostatin. Octacosa somatostatin appears therefore to be secreted into the hypothalamic-hypophyseal system, supporting the concept of a role for this peptide in regulating pituitary hormone secretion. 相似文献
9.
[目的]纯化培养食蟹猴支持细胞,并测定不同血清浓度对细胞增殖的影响。[方法]分离并纯化食蟹猴支持细胞后,分别以5%、10%、15%、20%4种不同血清浓度的培养基对食蟹猴支持细胞进行培养。利用MTT比色法判断支持细胞的增殖情况,从而确定最佳的血清培养浓度。[结果]5%血清浓度的培养基对细胞增殖能力的影响与10%血清浓度的培养基差异不显著,15%与20%的血清浓度的培养基对细胞增殖能力的影响差异不显著,5%、10%与15%、20%的血清浓度的培养基对细胞增殖能力的影响差异极显著。[结论]15%的血清浓度是支持细胞增殖的最佳比例。 相似文献
10.
研究了匍匐茎克隆草本植物蕨麻原变种（Potentilla anserine L． var.anserina）对干旱胁迫（即聚已二醇6000的浓度为0、5%、10%、15%、20%，10个重复)的表型可塑性：随着聚已二醇6000浓度的增加，实验植物的生物量显著减小；死亡率上升；基株叶片数目、基株叶片长度、基株叶片宽度具有显著的株间差异，呈二次曲线变化。因而在高寒地区的生态恢复中具有重要的意义。 相似文献
11.
12.
Reduced numbers of somatostatin receptors in the cerebral cortex in Alzheimer's disease 总被引：9，自引：0，他引：9
M F Beal M F Mazurek V T Tran G Chattha E D Bird J B Martin 《Science (New York, N.Y.)》1985,229(4710):289-291
Somatostatin receptor concentrations were measured in patients with Alzheimer's disease and controls. In the frontal cortex (Brodmann areas 6, 9, and 10) and temporal cortex (Brodmann area 21), the concentrations of somatostatin in receptors in the patients were reduced to approximately 50 percent of control values. A 40 percent reduction was seen in the hippocampus, while no significant changes were found in the cingulate cortex, postcentral gyrus, temporal pole, and superior temporal gyrus. Scatchard analysis showed a reduction in receptor number rather than a change in affinity. Somatostatin-like immunoreactivity was significantly reduced in both the frontal and temporal cortex. Somatostatin-like immunoreactivity was linearly related to somatostatin-receptor binding in the cortices of Alzheimer's patients. These findings may reflect degeneration of postsynaptic neurons or cortical afferents in the patients' cerebral cortices. Alternatively, decreased somatostatin-like immunoreactivity in Alzheimer's disease might indicate increased release of somatostatin and down regulation of postsynaptic receptors. 相似文献
13.
A. Dadkhah 《Russian Agricultural Sciences》2013,39(2):117-123
Two experiments, a Petri dish assay and a pot experiment were carried out to evaluate possible allelopathic effects of water extracts (0, 10 and 20 g L?1) of sugar beet (Beta vulgaris) and eucalyptus (Eucalyptus camaldulensis) on germination and growth of purslane (Portulaca oleracea). Results showed that germination percentage of purslane seeds was not inhibited by concentration of water extract of test plants. However, seed vigour and seedling growth strongly influenced by aqueous extracts of test plants. Maximum inhibitions on seedling growth were recorded when using the highest concentration of the aqueous extract (20 g L?1). It was apparent that sugar beet had a greater inhibitory effect than eucalyptus. Shoot length of purslane seedlings significantly decreased at 10 and 20 g L?1 aqueous extract concentration of sugar beet by 65.5 and 92.1% respectively compare to control, while eucalyptus decreased seedling shoot length of target weed at 10 and 20 g L?1 extract concentration by 29.8% and 52.9% respectively. Root length was more affected than shoot so that low aqueous extract concentration (10 g L?1) of sugar beet and eucalyptus decreased root length of target weed by 79.8% and 46% respectively. Foliar sprays with both 10 and 20 g L?1 of test plants extracts significantly decrease leaf area, leaves, stem and root dry weight of Portulaca oleracea. Maximum leaf area (1010 cm2) was obtained from the untreated plants (0% extract), while the lowest value (166.6 cm2) occurred with 20 g L?1 water extract of sugar beet. High aqueous extract concentration (20 g L?1) of sugar beet decreased leaves, stem and root dry weight of purslane plants by 96%, 86.7% and 91.9% respectively. 相似文献
14.
在鲫Carassius。啪￡峪适宜生存温度（室温为15—25℃）条件下,研究了10、20、30、40、50g／L的乌拉坦（Urethane）溶液（pH为7．0＋0．44）对鲫（体质量为230g±9．46g）的麻醉效果,探讨了乌拉坦对水生动物的麻醉作用,并提供日常实用的麻醉参数。结果表明：乌拉坦浓度为10～50g/L时,麻醉时间随着乌拉坦浓度的增大而缩短,复苏时间随着乌拉坦浓度的增大而延长,但浓度为50g／L时与浓度为40g／L时相比,鲫的复苏时间无显著性差异（P〉O．05）;浓度为10-40∥L时,各组鲫的复苏率均为100％,浓度为50g/L时,鲫的复苏率为88％;浓度为10-50g/L时,各组鲫7d的存活率均为100％。鲫在不同浓度（10～50g／L）的乌拉坦溶液中药浴一定时间后,将其暴露于空气中,经过一定时间后鲫可自动苏醒而弹起。其中除50g／L浓度组与40g／L浓度组之间,鲫的弹起时间无显著差异（P〉0．05）外,其余浓度组之间鲫的弹起时间均有显著差异（P〈0．05）;各浓度组药浴时间为10min与5min之间,鲫的弹起时间无显著差异（P〉0．05）,10g／L组的药浴时间为25min与20min之间,鲫的弹起时间无显著差异（P〉0．05）,各浓度组其余药浴时间之间均有显著差异（P〈0．05）。各试验组鲫7日存活率均为100％。药浴后的鲫能够恢复正常行为状态,表明乌拉坦对鲫行为的影响无明显的后遗效应。综合各项试验结果,表明乌拉坦对鲫的麻醉安全浓度为40g／L。 相似文献
15.
为提高干旱胁迫下桔梗种子萌发,研究了不同浓度水杨酸(10 mg/L、20 mg/L和30 mg/L)对干旱胁迫(5%、10%和20%PEG)下桔梗种子萌发和植物激素(脱落酸、赤霉素和吲哚乙酸)的影响。结果表明:20%PEG胁迫处理抑制桔梗种子萌发,外源添加水杨酸后,发芽率、发芽势、发芽指数、根长、苗长和鲜重均显著高于对照组,其中水杨酸浓度为10 mg/L时,各检测指标值最大; PEG胁迫处理下,10 mg/L和20 mg/L水杨酸处理后3种植物激素含量均显著低于对照组。在干旱胁迫下施加水杨酸处理可提高桔梗种子的抗干旱胁迫能力,并且对植物激素含量具有一定的调控作用。水杨酸浓度为10 mg/L时缓解干旱胁迫效果较好。 相似文献
16.
铅胁迫对金盏银盘的生长及其根系耐性的影响 总被引：1，自引：0，他引：1
通过水培模拟试验,在不同质量浓度(5、10、20、50、100 mg.L-1)铅(Pb)处理下,研究沼生药用植物金盏银盘(Bidens biternata)地上部与根系生物量、根系长度和根活力、根系的耐性指数、体内Pb的质量分数与分布。结果表明:Pb处理质量浓度≤20 mg.L-1时,对金盏银盘生长有促进作用。随着Pb处理质量浓度的升高,生物量和根长开始下降,当Pb处理质量浓度达100 mg.L-1时,其生物量和根长均极显著降低(P<0.01)。各质量浓度处理下的金盏银盘根系活力均低于对照,且都随着处理时间的延长而降低。随着Pb处理质量浓度的升高,金盏银盘体内各部位Pb质量分数基本表现为先升高后降低,其中叶和茎的Pb质量分数在Pb处理质量浓度为20 mg.L-1时达到最大;而根系在Pb处理质量浓度为10 mg.L-1时Pb质量分数最大,对铅的积累显著,质量分数高达2 080.89 mg.kg-1。在Pb处理同质量浓度下,Pb在各部位的质量分数由大到小的顺序是根系、茎、叶。各处理质量浓度下的转移系数均小于0.1。在Pb处理质量浓度为10~20 mg.L-1时,金盏银盘的根系耐性指数大于1.0;随着Pb处理质量浓度的增加,根系耐性指数降低。 相似文献
17.
18.
目的]确定降低苋菜硝酸盐累积效果最佳的施硫浓度,为完善苋菜科学施硫技术提供指导。[方法]采用盆栽方法,设置4个施硫肥水平,测定其对植株生长及硝酸盐、Vc含量的影响。[结果]施硫提高了苋菜的株高、单株重、最大叶长及最大叶宽。当硫浓度为20 mg/kg(S_2)时,株高最高,较不施硫处理(S_0)增加了14.3%。3个硫处理(S_1~S_3)硝酸盐含量降幅为20.6%~64.7%。施硫浓度为10 mg/kg时植株可食部分硝酸盐含量降低了64.7%。施硫处理苋菜V_C含量增加了19.7%~28.3%。[结论]大田苋菜适宜的施硫浓度为10~20 mg/kg。 相似文献
19.
为了研究一种适合澳洲长鳍鳗测量、标记、取血等试验操作的麻醉技术,进行了丁香酚对澳洲长鳍鳗麻醉效果的试验。结果表明,丁香酚对澳洲长鳍鳗有较好的麻醉效果(P<0.05),20~120 mg/L浓度平均都可在10 min内使其达到麻醉期,且麻醉后平均都能在10 min内完成复苏,复苏率达100%。麻醉和复苏所需时间除40、60、80、100 mg/L组之间差异不显著外,其他各组间以及其他各组与40、60、80、100 mg/L组之间差异均达到显著水平(P<0.05)。麻醉需时并非总是随丁香酚浓度增加而缩短,浓度从20 mg/L提高到30 mg/L,平均需时从312.88 s下降到252.25 s;到40 mg/L时,平均需时却陡增至582.00 s;浓度40~120 mg/L间,麻醉需时总体随丁香酚浓度增加而缩短,与浓度呈较强负相关关系(r=-0.84,P<0.05),至120 mg/L时降至267.50 s。麻醉后平均复苏需时以20 mg/L最短,为233.50 s,30 mg/L次之,为420.05 s;整体趋势与浓度并不呈明显的线性关系,而是与浓度及麻醉时间均有一定相关(r=0.52,P<0.05)。可见,丁香酚是安全、有效的澳洲长鳍鳗麻醉剂,浓度20~30 mg/L效果最佳,平均可在4~5 min达到麻醉期,麻醉后可在4~7 min复苏,可满足常规实验操作的需要。 相似文献
20.
用三种溶质不同浓度溶液,对三种植物进行了细胞质壁分离和复原的实验研究,结果表明,蔗糖、葡萄糖、氯化钠三种溶液在一定的浓度范围内,都可使三种植物细胞发生质壁分离,溶液浓度越高,质壁分离时间越短,蔗糖的最佳观察浓度为20%～30%;葡萄糖为10%～20%;氯化钠为2%～4%;三种植物在三种溶质的不同浓度下,细胞发生质壁分离的时间都是以水棉为最短,其次为洋葱和大蒜。 相似文献