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51.
三七.人参和西洋参细胞悬浮培养的比较研究   总被引:19,自引:1,他引:18  
用薄层层析对三七、人参和西洋参愈伤组织进行的初步鉴定表明,三种愈伤组织都含有皂甙和主要皂甙成分Rb_1、Rg_1,三七愈伤组织还含有一种抗癌皂甙Rh_1。对愈伤组织的生长,三七低于人参高于西洋参;对愈伤组织中总皂甙含量,三七均高于人参和西洋参。三种植物细胞悬浮培养结果类似于他们的愈伤组织培养,但生长又进一步提高。三七细胞悬浮培养中皂甙产生的时间进程几乎与生长平行,合适的收获期为培养30天。寡糖素不仅增强三七培养细胞的皂甙形成而且促进细胞生长,较合适的浓度为1.25 ppm。通过以上研究,使三七悬浮培养细胞的生长(干重增加178毫克)为最初培养愈伤组织的4倍以上,总皂甙产率高达20.6毫克,为最初培养愈伤组织的8.5倍。  相似文献   
52.
三七愈伤组织的培养   总被引:17,自引:1,他引:16  
在MS培养基中加入不同浓度的KT和2,4-D,综合考虑三七愈伤组织生长缓慢兼顾皂甙含量,较合适的KT浓度为0.7ppm,较合适的2,4-D浓度在2—3ppm之间。在培养基中补充各种添加剂,结果以椰子乳和水解乳蛋白较好。综合生长和皂甙含量以20%的椰子乳和0.7%的水解乳蛋白较合适。从21个三七愈伤组织无性繁殖系中筛选山了5个较优的无性系,特别是其中04号无性系更优,无论生长速率还是总皂甙含量都更高。通过以上研究,使三七愈伤组织的生长速率达220毫克/升/天,是原初培养愈伤组织(54.0mg干重/升/天)的4倍。愈伤组织中总皂甙含量高达13%,是原初培养愈伤组织(5.37%)的2.4倍,为原植物的3倍。从而证明了三七培养组织次级代谢的全能性是可调节的,为三七细胞工程的工业生产应用打下了初步基础。  相似文献   
53.
寡糖素对滇紫草愈伤组织色素合成的影响   总被引:3,自引:0,他引:3  
从黑节草、红花和人参中提取的寡糖素对滇紫草愈伤组织的色素合成均能起促进作用,当它们单独使用时,分别找到了它们作用于愈伤组织以生产色素的最适浓度.本研究对将来采用组织培养方法进一步工业化生产紫草素提供了依据。  相似文献   
54.
用细胞外记录技术研究了金黄地鼠一侧视皮层神经元对电刺激另一侧相应部位的反应及其对视觉刺激反应的特点。(1)在17—18a 交界区大多数(78%)细胞能被电刺激对侧相应点所驱动。在17区内部,被驱动细胞数随离开17—18a 交界距离增加而减少。(2)按对电刺激的反应形式,记录的细胞可分为四类:a.逆行驱动细胞,占17—18a 交界区记录细胞数的20%;b.顺行驱动细胞,占52%中;c.自发发放因电刺激而减少或完全停止的细胞,占6%,d.其余细胞(22%)对电刺激没有可察觉的反应。(3)在17—18a 交界,除了Ⅰ层以外的各层都可记录到顺行驱动细胞,而逆行驱动细胞则主要集中在Ⅲ及Ⅴ层。(4)17—18a 交界细胞感受野(RF)多位于垂直中线附近的对侧视野内,有些 RF 跨越中线,其边界延伸到同侧约10°处。(5)逆行驱动细胞包括刁和 Blakemore 以前在视皮层中记录到的所有细胞类型和各种程度的眼优势,但单眼细胞的比例增加,非对称式 RF 和中心对称式的给-撤型 RF 的比例有所减少。  相似文献   
55.
56.
从上部低次烟叶中筛选出耐高温淀粉酶产生菌GW-2和耐高温蛋白酶产生菌GW-3,通过对菌落的形态观察、16S rRNA的鉴定和同源性分析,初步确定GW-2为解淀粉芽胞杆菌,GW-3为枯草芽胞杆菌。对上部低次烟叶进行双菌种固态发酵,并优化发酵条件,最佳发酵条件:GW-2菌悬液(OD600=1)接种量为7.5 m L/g,GW-3菌悬液(OD600=1)接种量为10 m L/g,物料填充度为500 m L三角瓶中装50 g烟叶干基,当烟叶发酵水分质量分数为45%时,48℃发酵5 d。在该发酵条件下,上部低次烟叶的淀粉降解率为22.33%,蛋白质降解率为16.74%。烟叶淀粉和蛋白质的质量分数较大幅度下降,其含量指标接近优等烟叶的含量。该发酵方式比传统的贮存式烟叶发酵大大缩短了发酵时间。  相似文献   
57.
Trisomy of chromosome 8 is frequently reported in myeloid lineage disorders and also detected in lymphoid neoplasms as well as solid tumors suggesting its role in neoplastic progression in general. It is likely to be a disease-modulating secondary event with underlying cryptic aberrations as it has been frequently reported in addition to known abnormalities contributing to clinical heterogeneity and modifying prognosis. Here, we share our findings of trisomy 8 in leukemia patients referred for diagnostic and prognostic cytogenetic assessment. Total 60 cases of trisomy 8, as a sole anomaly or in addition to other chromosomal aberrations, were reported (January 2005-September 2008). Unstimulated bone marrow or blood samples were cultured, followed by GTG banding and karyotyping as per the ISCN 2005. Patients with +8 were chronic myeloid leukemia (CML) (36), acute myeloid leukemia (AML) (17), and acute lymphoblastic leukemia (ALL) (7). In 7 patients, trisomy 8 was the sole anomaly, whereas in 6 patients +8 was in addition to normal clone, in 47 patients, the +8 was in addition to t(9;22), t(15;17), and others, including 3 with tetrasomy 8. Only one patient showed constitutional +8. The present study will form the basis of further cumulative studies to correlate potential differential effects of various karyotypic anomalies on disease progression and survival following a therapeutic regime. To unravel the role of extra 8 chromosome, constitutional chromosomal analysis and uniparental disomy will be considered.  相似文献   
58.
Duan B  Huang L  Chen S 《Phytomedicine》2012,19(6):562-568
The after-harvesting sun-dried processing of Fritillariae thunbergii bulbus (Zhebeimu) was the traditional treatment for commodity. Over recent decades the natural drying process for bulbus of Fritillariae has been replaced by sulfur-fumigation for reducing the drying duration and pest control. We used ultra-performance liquid chromatography coupled with evaporative light scattering detection (UPLC-ELSD) fingerprinting analysis and major alkaloids determination to investigate the potential damaging effect of the sulfur-fumigating process. The experimental conditions were as follows: Chromatography was proceeded on Waters Acquity UPLC BEH C(18) column; the linear gradient elution was conducted with mobile phase prepared from acetonitrile-0.02% triethylamine; the drift tube temperature was set at 40°C with a nitrogen flow-rate of 30psi, and the spray parameter was set 40%. All calibration curves showed good linear regression (R>0.9991) within the tested range. The method was validated for precision, accuracy, limit of detection and quantification. The study also has shown that sulfur-fumigated samples had significant loss of the main active compounds and a more destructive fingerprint profile when compared to the sun-dried samples.  相似文献   
59.
The Philadelphia (Ph) chromosome, a hallmark chromosomal anomaly observed in 95 percent of chronic myeloid leukemia (CML) cases, is known to involve the Abelson (ABL) proto-oncogene on chromosome 9 and the breakpoint cluster region (BCR) gene on chromosome 22, producing BCR/ABL mRNA encoding an abnormal tyrosine kinase protein. In the process of generating BCR-ABL fusion, the deletion of residual BCR or ABL occurs in 15-30 percent of CML patients. In addition, some rearrangements are complex, and do not yield the ABL/BCR fusion due to the involvement of a third chromosome in the rearrangement. The possible role of these deletions and complex rearrangements in disease outcome is an ongoing topic of research. We report our results of cytogenetic analysis with GTG banding and fluorescence in situ hybridization using dual color dual fusion probe (D-FISH) from Vysis Inc, USA in 169 (109 male and 60 female) CML patients registered at The Gujarat Cancer and Research Institute (GC and RI) from April 2004 to December 2005. GTG banding was carried out in 123 cases having analyzable metaphases. Of these 123 cases, D-FISH revealed atypical signal patterns in 57 patients (46%), and 12 cases revealed additional complex translocations indicative of disease progression. Out of 57 cases with atypical FISH patterns, 22 included metaphase FISH results, and the rest had only interphase FISH performed. In addition to the hallmark Philadelphia chromosome, other chromosomal aberrations in CML revealed heterogeneity of molecular events. Pooling of more data may lead to identification of new CML sub-groups and hence help in the analysis of clinical trials. Patients enrolled in our prospective study of prognostic significance will be followed up for disease free and overall survival in correlation with ABL-BCR deletion status.  相似文献   
60.
对山东省黄瓜(Cucumis sativus L.)叶围煤污菌种群组成、分布、演替和对黄瓜的生理影响的研究结果表明;8个地市黄瓜叶面真菌有15属21种,其中属煤污菌的有6属10种:链格孢(Alternaria alternata Karst.),出芽短梗霉[Aureobasidium pullulans(deBary)Arn.],芽枝状枝孢[Cladosporium cladosporioides(Fres.)de Vries]尖孢枝孢(C.oxysporum Berk.&Curt.)大孢枝孢(C.macarocarpum Preuss),多主枝孢[C.herbarum(Pers.)Link.],球孢枝孢(C.sphaerospermum Perz.),灰腐质霉(Humicola grisea Traaen.),紫附球菌(Epicoccum purpurascens Ehrenb.ex Wallr.)和弯孢霉[Curvularia lunala (Walk.)Boed.].链格孢和枝孢霉(Cladosporium spp.)是各地区主要种群.黄瓜叶面真菌的种类和密度与苗龄、叶面可溶性糖和氨基酸组分含量成极显著正相关.随着苗龄的增长,真菌的密度和种类增多.用两个主要种群的分生孢子悬浮液接种黄瓜叶面,形成明显的煤污,导致叶面光合作用降低,呼吸作用升高,气孔阻力增大,蒸腾作用下降.穗状德氏霉(Drechsleraspicifer R.Nelson)和核茎点霉(Phoma pulaminum Speg.)是国内的新记录.  相似文献   
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