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1.
圆果雪胆中的皂甙成分   总被引:4,自引:1,他引:3  
从圆果雪胆(Hemsleya amabilis)的块茎中分离到10个化合物,其中3个雪胆皂甙是首次从该种植物中得到,它们的结构通过光谱和化学的方法鉴定为齐墩果酸-3-O-α-吡喃阿拉伯糖(1→3)-β-葡萄糖醛酸甙,28-O-β-D-吡喃葡萄糖齐墩果酸3-O-α-吡喃阿拉伯糖(1→3)-β-D-葡萄糖醛酸,28-O-β-D-吡喃葡萄糖齐墩果酸3-O-「β-D-吡喃葡萄糖(1→2)」-「α-吡喃阿  相似文献   

2.
木瓜中齐墩果酸的提取分离及含量测定   总被引:14,自引:0,他引:14  
有渗漉法对木瓜中的齐墩果酸进行了提取,用层析柱法对提取物进行分离,方法较简便。并以标准品作对照,采用薄层比色法对其进行含量测定,该法操作简便,结果稳定。经测定木瓜中的游离齐墩果酸的含量为0.935%。  相似文献   

3.
苹果渣发酵生产饲料蛋白的工艺条件   总被引:19,自引:0,他引:19  
采用经试验所筛选出的菌种组合,通过试验,获得了苹果渣发酵的适宜工艺条件:接种比例为1:5-1:10,接种量15-30%,料水比10:7-10:8,pH值为6-7,发酵时间3-4d,静止发酵料层厚度不超过30mm。发酵产物测定结果显示,粗蛋白含量达到29.30%,提高到45.77%。蛋白质含量达到27.56%,提高了82.88%,粗纤维含量降低了23.27%。  相似文献   

4.
从栀子细胞培养物中分离多糖最佳工艺条件的研究   总被引:5,自引:0,他引:5  
对栀子细胞培养物多糖的提取、纯化条件进行优化研究,结果表明,提取的最佳工艺是80℃下的碱性水中浸提2h,加水量为50倍,醇析用乙醇的浓度为70%-80%,蛋白质去除过程中氯仿/正丁醇(V/V),样品/氯仿-正丁醇(V/V)分别为1:0.4和1:0.24时,效果最好。  相似文献   

5.
甜菊含甙量的变异及R-A型良种的选育   总被引:3,自引:1,他引:2  
从甜味成分种类及含量的不同,研究甜菊(SteviarebaudianaBertoni)实生群体和单株无性系的变化,从中选育优质甜味成分含量高的良种。主要结果:(1)在实生群体中,丰产株型(圆纺锤形株)占7.3%,其中,优质甜味成分R-A含量超过St含量的R-A型株占10.96%,它们的R-A含量变幅为3.3~12.0%。(2)R-A型良种J-2单株无性系在繁殖达2000万株时,叶片大小和含甙量均存在极显著差异,R-A含量变幅为4.5~12.2%。(3)从R-A含量为3.86%的实生群体中选出R-A含量为7.04~12.03%的单株及从R-A含量为9.10%的良种单株无性系中选出R-A含量为10.15~12.15%的单株,它们的R-A含量均大幅度提高。  相似文献   

6.
本文研究了超声波法提取刺葡萄籽中多酚类物质的方法,考察了提取剂、提取时间、料液比等因素对提取率的影响。结果表明,用超声波法进行多酚类物质提取的最佳工艺条件为:以70%的丙酮水溶液为提取剂,料液比为1:10,室温下超声波提取两次,每次30min。采用Folin—Ciocaheau方法测定粗提物中多酚的含量,得出刺葡萄籽多酚粗提物得率为4.95%,纯度为49.89%。本文还对多酚粗提物中活性成分齐墩果酸进行了进一步的分离、鉴定与检测。  相似文献   

7.
对载植在红壤丘陵地的大核青、横核、红面珠墩、鹅嗉等四个青梅品种三年生树的生长结果习性调查表明:大核青树冠扩大最快,横核和红面珠墩次之,鹅嗉最慢;短果枝占各类枝梢比率各品种分别为73.9%、70.2%、31.6%、48.5%;不完全花率9.3%、10.2%、8.3%和18.7%;每100朵花花粉重量分别为86.1、84.2、73.8和64.2mg;第一年结果的单株产量依次为7.25、11.75、0.  相似文献   

8.
目的:研究了纤维素酶在提取生物碱过程中的应用。方法:采用酶浸法和氯仿法两种不同的工艺提取马钱子生物总碱,高效液相色谱法(HPLC)测定了马钱子生物总碱中士的宁的含量。结果:酶浸法提取士的宁和氯仿法提取士的宁的含量分别为1.83%、1.32%;酶浸法和氯仿法提取马钱子生物总碱的产率分别为:2.85%、1.86%。  相似文献   

9.
野桂花化学成分研究   总被引:1,自引:1,他引:0  
从野桂花(Osmanthus yunnanensis)地上部分95%乙醇提取物中首次分离得到18个化合物,应用波谱方法及与已知品对照的手段鉴定它们为:E-阿魏酸二十烷基酯(1)、β-谷甾醇(2)、羽扇豆醇(3)、齐墩果酸(4)、7-oxo-β—sitosterol(5)、乙酰齐墩果酸(6)、(6'-O-palmitoyl)-sitosterol-3-O-β—D—glucoside(7)、rotundioic acid(8)、地榆糖甙II(9)、3β-hydroxy-27-p-(E)-eoumaroyloxyolean-12-en-28-oicacid(10)、3β—laydroxy-27-p-(Z)-coumaroyloxy-olean-12-en-28-oicacid(11)、hycandinic acid ester(12)、绿原酸丁酯(13)、4,5-二咖啡酰奎尼酸丁酯(14)、28-O-β-D—glueopyranosyl rottmdioic acid(16)以及三个半萜类化合物:4,5-dihydroxyprenyl caffeate(15)、4-(6-O-caffeoyl -β-D—glucopyranosyloxy)-5-hydroxyprenyl caffeate(17)、4-β-D—glucopyranosyloxy5-hydroxyprenyl caffeate(18)。  相似文献   

10.
缓激肽对大鼠背根神经节分离神经元ATP激活电流的调制作用   总被引:14,自引:1,他引:13  
Gu QH  Li ZW  Fan YZ 《生理学报》1998,50(1):37-42
在新鲜分离大鼠背根神经节(DRG)的56个细胞标本上,应用全细胞膜片箝技术进行记录。胞外加缓激肽(BK,10^-6 ̄10^-4mol/L)引坊的DRG细胞膜反应结果如下:(1)71.4%的细胞为内向电流,其电流反应的幅值具有明显的浓度信赖性;(2)12.5%的细胞为外向电流;(3)16.1%的细胞未引起可检测的膜反应,单独给予ATP(10^-6 ̄10^-3mol/L)在大多数受栓细胞(54/56)  相似文献   

11.
Manometric measurements were made of oxygen uptake (Q OO2) and aerobic lactic acid output (QG) by slices of cerebral cortex and medulla oblongata of the cat in the presence of mixtures of 1, 5, and 20 volumes per cent of carbon dioxide in oxygen. The concentrations of NaHCO3 and NaCl in the medium were varied to maintain constant pH and sodium ion concentrations. The calcium ion concentration was 0.0002 M. At pH 7.5 under these conditions, an increase in carbon dioxide from 1 per cent to 5 per cent doubled the QG of both tissues but did not alter Q OO2; an increase from 5 per cent to 20 per cent carbon dioxide had no further effect on QG in either tissue or Q OO2 of cortex, but did depress the Q OO2 of medulla. At pH 8.1, an increase in carbon dioxide from 1 per cent to 5 per cent raised the Q OO2 and QG of cortex by about 60 per cent. Measurements at low oxygen tension carried out previously in phosphate medium were repeated in bicarbonate medium to obtain data for the combined output of lactic acid and carbon dioxide (QA). When the oxygen in the gas phase was decreased from 95 to 3 volumes per cent, the lactic acid output as measured colorimetrically increased by 114 mg./gm. in cortex and by 8 mg./gm. in medulla; QA increased from 12.3 to 13.5 in cortex and decreased from 5.1 to 3.8 in medulla.  相似文献   

12.
1. A wide variety of procedures was used to test the motility of mammalian sperm after plunging them into liquid nitrogen at –195°C. and later rapidly warming them to 35°C. by plunging them into a suitable balanced and isotonic medium. 2. Using seminal fluid sperm from the same human donor, maximal numbers of motile sperm survived vitrification when the samples were (a) very fresh, (b) untreated with plasmolysing solutions, (c) plunged into the refrigerant in the form of a foam. The maximum yield of motile human sperm recoverable from the liquid nitrogen was 50 per cent. Since in this sample only 75 per cent of the sperm were alive before immersion, 67 per cent of the living sperm survived vitrification. 3. Experiments with sperm from 31 rabbits were made with a variety of conditions of pretreatment to obtain maximal yields of recoverable, motile sperm after vitrification by liquid nitrogen. (a) A consistent recoverable yield of about 0.5 per cent was obtained when the untreated suspension of sperm was smeared on cellophane and partially dried in air before immersing in liquid nitrogen. (b) On a few out of many occasions plasmolysis for several minutes with hypertonic Ringer solution gave a recoverable yield of 0.1 per cent as did (c) pretreatment with hypertonic Ringer and butyric acid.  相似文献   

13.
Of 100 patients given tetanus antitoxin, 56 were given an antihistaminic drug in oral doses of 50 mg. daily for ten days following injection. The other 44 were not given antihistamine. The incidence of serum reaction in the former group was 3.6 per cent; in the latter, 20.4 per cent.  相似文献   

14.
重液浮选对花粉浓度计算的影响   总被引:2,自引:0,他引:2  
用重液浮选方法可获得富集、清洁的孢粉制片,但在浮选过程中不可避免地会在丢弃的底样中留下相当数量的孢粉。本文定量地探讨这些残留孢粉在重液不同比重条件下对花粉浓度计算的影响,结果表明,在重液浮选中,不同类型孢粉的漂浮率有所不同,并因此造成浓度计算中的误差,误差的大小因孢粉类型和重液比重的不同而不同,大体在1—15%之间。  相似文献   

15.
Lactic acid production by rat retina in a medium containing phosphate was studied chemically. One half as much lactic acid was found as in a medium containing bicarbonate. In our experience the rate of respiration in a phosphate medium was sensitive to oxygen tension, for it was 38 per cent lower at 10 per cent and 51 per cent lower at 5 per cent oxygen than at 100 per cent oxygen. Previously Laser had reported no decrease in respiration at 5 per cent oxygen in phosphate medium. In phosphate medium, when the oxygen tension was varied, respiration and glycolysis bore a reciprocal relationship to each other. In bicarbonate medium, when the oxygen tension was lowered from 95 per cent to 5 per cent there was no significant change in the respiration, but glycolysis was increased nearly to the anaerobic level. This agrees with the earlier experiment of Laser in bicarbonate medium and adds support to his conclusion that the rate of glycolysis is controlled by oxygen tension rather than by the rate of respiration, under the conditions of the experiment.  相似文献   

16.
By means of 1 M NaCl isolated lymphocyte chromosomes can be separated into two fractions, each of which contains nucleoprotein. The fraction soluble in M NaCl consists largely of desoxyribose nucleohistone, and constitutes 90 to 92 per cent of the mass of the chromosome. The insoluble residue (the residual chromosome is a coiled thread containing some 12 to 14 per cent of ribose nucleic and about one-fifth as much desoxyribose nucleic acid; the residual chromosome accounts for 8 to 10 per cent of the mass of the chromosome. The staining of chromosomes—whether by the Feulgen procedure, by hematoxylin, orcein, or by basic dyes such as crystal violet—is due to the nucleohistone fraction which contains about 96 per cent of the nucleic acid of the chromosome. The form of the chromosome is due primarily to the protein thread of the residual chromosome. This thread is the only linear structure of microscopic dimensions in the chromosome that is not readily dispersed. When chromosomes are broken, it must be supposed that a break is made in the protein thread of the residual chromosome. The foregoing provides evidence for considering the residual chromosome to be the basis of the linear order of the genes. This would mean either that the residual chromosome is a structure around which the genes are organized or that the genes form part of its substance.  相似文献   

17.
Growth curves consist, in all cases, of two major segments. The first major segment is, in the case of higher animals and plants, made up in turn of several (probably five) shorter segments during each of which growth takes place at a constant percentage rate. The transitions between the successive stages are abrupt, the abruptness being of the order of metamorphosis in cold blooded animals. It has been made clear in the first paper of this series that the time rate of growth following the major inflection declines at a constant percentage rate. The junction between the two major segments occurs at puberty in animals and flowering in plants. The two major segments are not symmetrical about the major inflection. The slope of the segment following the inflection is always less than the slope of the segment preceding the inflection. The major inflection does not occur in the center of the growth curve. The instantaneous rate of growth at the beginning of growth is of the order of 100–200 per cent per day (i.e. the body weight is doubled in from 7 to 17 hours). It may be mentioned that 2 months after conception the rate of growth in man is only 8 per cent per day. This is contrary to all the published statements. Thus, Minot concluded that growth begins at 1000 per cent per day; Jackson concluded that in man, growth during the 1st month takes place at 57.5 million per cent per month; during the 2nd month 990 per cent per month; during the 3rd month 390 per cent per month (8 per cent per day is only 240 per cent per month). The reason for the discrepancy between the values derived, by the method adopted by the writer, and the values given in the literature is explained by Fig. 1.  相似文献   

18.
Abstract— [14C]Leucine was injected intracranially into the brainstem reticular formation at the level of the upper medulla by the stereotaxic method. Subcellular fractions prepared 3 hr after injection showed that the specific activities of leucine-incorporated proteins decreased in the order soluble, microsomal, nuclear and mitochondrial fractions. Specific activities of proteins in the sera were 2·2 per cent of whole homogenate proteins.
The results from 27 experiments showed that 66·6 per cent of the mean specific activities of proteins extracted from whole homogenates fell within ·1 s.d . and 100 per cent within ± 2 s.d . (close to a normal distribution). The coefficients of variation were between 40 and 50 per cent for whole homogenates, sera and all subcellular fractions. Reproducibility of results and factors concerned with possible errors in the technique are discussed.  相似文献   

19.
Abstract— The contents of GABA, homocarnosine, and β-alanine can be raised in rat brain for long periods of time by the continued administration of phenelzine, aminooxyacetic acid (AOAA), or isonicotinic acid hydrazide (INH). These 3 compounds apparently act by preferential inhibition of the enzyme GABA aminotransferase (GABA-T). Oral administration of phenelzine (20 mg/kg per day) caused a 25–50 per cent increase in GABA levels in rat brain, but produced appreciable toxic side effects. A similar increase in GABA levels in brain resulted from oral administration to rats of INH in a dosage of 60 mg/kg per day, without production of any obvious toxic effects. Simultaneous administration of large doses of pyridoxine did not abolish the GABA-elevating effect of INH. Brain GABA levels in the rat were increased by approx. 50 per cent by daily injections of AOAA (2.5 mg/kg per day). At this low dosage, AOAA injections in rats could be continued for at least 6 weeks without producing evident toxic effects. Oral administration of large amounts of GABA, on the other hand, failed to increase the content of GABA in the brains of rats not treated with GABA-T inhibitors, and failed to produce any further increase of brain GABA levels in rats treated with AOAA.  相似文献   

20.
The author report clinical experience with 212 cases of mammary cancer metastatic to bone, in 186 of which radiotherapy was given, and in 26 steroid hormone therapy.At least 70 per cent of patients with bone metastasis from breast cancer were relieved of pain by adequate roentgen therapy, the relief lasting for most of the survival time in many instances.About 25 per cent of patients had recalcification or reossification of bony lesions with roentgen therapy; while dramatic, this is not always an indication that relief of pain will continue or that survival time will be lengthened.If and when adequate radiotherapy has not been effective or cannot be administered (for example, in a patient with extremely widespread metastasis, or one residing at a considerable distance from radiotherapeutic service) steroid hormone therapy in adequate dosage is frequently beneficial. From 40 per cent to 75 per cent of patients with bone metastases from breast cancer are relieved of pain by steroid hormone therapy. In about 15 per cent of cases recalcification of the lesion occurs.Effective roentgen therapy may usually be given in a relatively brief period of time (one to two weeks). Effective steroid hormone therapy usually requires from 12 to 24 weeks.Complications of steroid hormone therapy are numerous. Some patients are made considerably worse by such therapy. These complications may only be controlled by reduction or discontinuation of the hormones. For this reason, it is recommended that irradiation always be used as the initial method of palliation.  相似文献   

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