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101.
本实验采用D-氨基半乳糖(D-GalN)诱导的大鼠急性肝损伤模型,观察大鼠肝脏组织化学的变化,探讨肝炎平对急性肝损伤的保护作用。实验分为四组,即正常对照组、模型组、肝炎平及肝得健保护组。结果表明:肝炎平对肝细胞膜系统有一定的保护作用。肝炎平组和肝得健组SDH、CCO及ChE活性明显高于模型组,且与正常对照组相近。本实验模型组ACP的活性明显高于正常组,而肝炎平组ACP的活性明显低于模型组,与正常对照组无显著性差异。提示:肝炎平可显著改善因D-氨基半乳糖所致肝损害的作用。且其对肝细胞的保护作用与肝得健一致。 相似文献
102.
肝细胞增殖抑制因子(Hepaticproliferationinhibitor,HPI)粗制品、半纯品和纯品对体外培养的人肝癌细胞具有显著抑增殖作用,随样品纯度提高抑制活性逐渐增强。纯品(浓度5μg/ml)的抑制率达77.71%。正常成年大鼠肝细胞呈HPI阳性表达。在DEN诱发大鼠肝细胞癌的发生发展过程中,转化的癌前期细胞和肝癌细胞呈HPI阴性表达。表明肝细胞HPI的表达能力在其癌变过程中消失,从而失去了自身的抑癌作用。 相似文献
103.
104.
固定化酵母细胞生产1,6-二磷酸果糖研究 总被引:2,自引:0,他引:2
本文研究了固定化酵母细胞制备果糖1,6二磷酸(FDP)的方法及其生产。用卡拉胶包埋方法固定化酿酒酵母(Sacchromyces cerevisae),对含葡萄糖1.0M,磷酸盐0.8M的糖磷液,pH6.5,在37℃下进行磷酸化反应。反复分批转化20天以上,可达到平均产FDPH_427.58mg/ml,最高为59.94mg/ml。用100ml固定化细胞生物反应器连续运转309h,稀释速率D=0.097h~(-1),平均产FDPH_4 21.51mg/ml。20L反应器连续运转,生产能力达到1.7g/h.L。用层析方法制备FDPNa_3结晶粉,提取收率为72.08%,制备质量达到或超过了国内外同类产品的质量要求。 相似文献
105.
Rui Yan Mark Ottenbreit Bharati Hukku Michael Mally Sharong Chou Joseph Kaplan 《In vitro cellular & developmental biology. Animal》1996,32(10):656-662
Summary Methods for monitoring cell line identification and authentication include species-specific immunofluorescence, isoenzyme
phenotyping, chromosome analysis, and DNA fingerprinting. Most previous studies of DNA fingerprinting of cell lines have used
restriction fragment length polymorphism analysis. In this study, we examined the utility of an alternative and simpler method
of cell line DNA fingerprinting—polymerase chain reaction (PCR) amplification of fragment length polymorphisms. Fourteen human
cell lines previously found by other methods to be either related or disparate were subjected to DNA fingerprinting by PCR
amplification of selected fragment length polymorphism loci. Cell identification patterns by this method were concordant with
those obtained by isoenzyme phenotyping and restriction fragment length polymorphism-DNA fingerprinting, and were reproducible
within and between assays on different DNA extracts of the same cell line. High precision was achieved with electrophoretic
separation of amplified DNA products on high resolution agarose or polyacrylamide gels, and with fragment length polymorphism
(FLP) loci-specific “allelic ladders” to identify individual FLP alleles. Determination of the composite fingerprint of a
cell line at six appropriately chosen fragment length polymorphism loci should achieve a minimum discrimination power of 0.999.
The ability of PCR-based fragment length polymorphism DNA fingerprinting to precisely and accurately identify the alleles
of different human cell lines at multiple polymorphic fragment length polymorphism loci demonstrates the feasibility of developing
a cell line DNA fingerprint reference database as a powerful additional tool for future cell line identification and authentication. 相似文献
106.
神经节苷脂GM_3对小鼠腹腔常驻巨噬细胞(R-M)和Ge-132体内激活的巨噬细胞(Ge-132-M)的磷脂代谢转换有显著的影响,当这两种M在体外用GM_3处理时,表现出[ ̄(32)P]Pi和[ ̄3H]肌醇参入PI降低,参入PIP、PIP_2增加;但在[ ̄(32)P]Pi和[ ̄3H]胆碱参入PC上,R-M与Ge-132-M不同,即GM_3促进同位素前体参入R-M的PC,抑制它们参入Ge-132-M的PC.以上结果表明GM3可能提高了PI或PIP的磷酸激酶的活性,致使[ ̄(32)P]PIP和[ ̄(32)P]PIP_2增多,[ ̄(32)P]PI减少.激活的M(Ge-132-M)本身PC代谢转换率较R-M高,当Ge-132-M再受GM_3刺激,PC代谢转换率降低,这提示GM_3对激活的M的PC代谢转换有调节作用. 相似文献
107.
作者对湖南省冷水江市大嵊山大气污染与马尾松衰亡进行了研究,研究结果表明大气综合污染指数在3个研究点上分别为1.00(对照)、1.76和2.23。而以林分密度、林分非衰亡率、针叶长度、针叶干重、马尾松平均高、平均胸径等因子计算出的林分外貌综合得分从173.9下降到143.5和132.5。在一年四季,马尾松针叶中叶绿素含量也是清洁区显著高于污染区,而叶绿素a/b值则是污染区的高,峰值较正常的提前。马尾松在受到大气污染作用后,针叶中营养元素含量呈下降趋势,尤其是氮。根据树干解析发现大气污染对马尾松高生长和胸径生长都具有抑制作用,但并不表现出同步效应,对高生长的抑制有一个滞后现象,时间在2~3年。另外,大气污染对马尾松的结果影响很大,污染区的马尾松单株拥有球果数仅为清洁的25%,用灰色系统理论对马尾松材积与相关影响因子进行关联度分析发现,材积与综合污染指数的倒数有很好的关联性,关联度达到了0.773。 相似文献
108.
Nutrient uptake relationship to root characteristics of rice 总被引:1,自引:0,他引:1
Data on root parameters and distribution are important for an improved understanding of the factors influencing nutrient uptake
by a crop. Therefore, a study was conducted on a Crowley silt loam at the Rice Research and Extension Center near Stuttgart,
Arkansas to measure root growth and N, P and K uptake by three rice (Oryza sativa L.) cultivars at active tillering (36 days after emergence (DAE)), maximum tillering (41 DAE), 1.25 cm internode elongation
(55 DAE), booting (77 DAE) and heading (88 DAE). Soil-root core samples were taken to a depth of 40 cm after plant samples
were removed, sectioned into 5 cm intervals, roots were washed from soil and root lengths, dry weights and radii were measured.
Root parameters were significantly affected by the soil depth × growth stage interaction. In addition, only root radius was
affected by cultivar. At the 0- to 5-cm soil depth, root length density ranged from 38 to 93 cm cm-3 throughout the growing season and decreased with depth to about 2 cm cm-3 in the 35- to 40-cm depth increment. The increase in root length measured with each succeeding growth stage in each soil
horizon also resulted in increased root surface area, hence providing more exposed area for nutrient uptake. About 90% of
the total root length was found in the 0- to 20-cm soil depth throughout the season. Average root radius measured in the 0-
to 5-cm and 35- to 40-cm depth increments ranged from 0.012 to 0.013 cm and 0.004 to 0.005 cm, respectively throughout the
season. Total nutrient uptake by rice differed among cultivars only during vegetative growth. Differences in total nutrient
uptake among the cultivars in the field appear to be related to absorption kinetics of the cultivars measured in a growth
chamber study.
Published with permission of the Arkansas Agricultural Experiment Station. 相似文献
109.
RFLP tagging of a salt tolerance gene in rice 总被引:10,自引:0,他引:10
A salt tolerant rice mutant (M-20) was obtained through selection in vitro. Its tolerance was stably inherited over eight generations and most traints between M-20 and its sensitive original 77–170 (Oryza sativa) were very similar. By deriving an F2 population of M-20 × 77–170 and splitting every F2 individual into two parts, with one part planted in normal conditions and another part in saline conditions, the inheritance of salt tolerance in rice was studied. Under normal conditions, there was no apparent segregation among F2 individuals. Under saline conditions, however, the segregation of traits was obvious. According to our standards, the ratio of salt sensitive:moderately-tolerant:tolerant plants was 25:42:18, in accordance with a 1:2:1 ratio. It suggested that the improvement of salt tolerance in our materials was induced by the mutation of a major tolerant gene which showed incomplete dominance. By use of 130 RFLP probes distributed throughout the rice genome, the gene was tagged by a single copy DNA probe, RG4, which was located on chromosome 7. The genetic distance between the salt tolerant gene and RG4 was 7.0 ± 2.9 cM. Based on the split method, a method which could be currently used to evaluate the damage of salt stress in rice was proposed. 相似文献
110.