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131.
Propagation of potato tubers in a nutrient mist bioreactor 总被引:1,自引:0,他引:1
Zhenlong Hao Fan Ouyang Yuxuan Geng Xiangdong Deng Zanmin Hu Zhenghua Chen 《Biotechnology Techniques》1998,12(8):641-644
The newly designed nutrient mist bioreactor provided an environment supporting multiple-layer culture. In vitro tubers of potato (Solanum tuberosum L.) were induced and cultured in this bioreactor by using two culture methods. The percentage of the inocula eventually forming tubers in a two-step method was 98% with only 54% being formed in a one-step method. The two-step method improved the efficiency of tuber induction, expedited and synchronized the tuberization. © Rapid Science Ltd. 1998 相似文献
132.
为了改进精制白喉毒素脱毒工艺中存在的时间长和损失大等问题,我们考虑进行脱毒过程中加入L-赖氨酸协同脱毒的试验,并以原工艺进行比较,结果使原工艺存在的问题均得到较好的解决。 相似文献
133.
枳壳外植体离体再生及农杆菌介导的遗传转化 总被引:5,自引:0,他引:5
以枳壳实生苗的上胚轴及茎段为材料,在附加有BA和MT培养基上进行培养,上胚轴出芽率普遍高于茎段,BA为1mg/L时,出芽率最高,BA浓度升高,出芽率随之下降。外植体在培养基上的接种方式,对出芽有一定影响,上胚轴切段 形态学下端垂直插入,出芽率高。 相似文献
134.
Hai-Yun Xiao Aaron Balog Ricardo M. Attar David Fairfax Linda B. Fleming Christian L. Holst Gregory S. Martin Lana M. Rossiter Jing Chen Mary-Ellen Cvjic Janet Dell-John Jieping Geng Marco M. Gottardis Wen-Ching Han Andrew Nation Mary Obermeier Cheryl A. Rizzo Liang Schweizer Thomas Spires Weifang Shan Gregory Vite 《Bioorganic & medicinal chemistry letters》2010,20(15):4491-4495
A novel series of 4-[3,5-dioxo-11-oxa-4,9-diazatricyclo[5.3.1.02,6]undec-4-yl]-2-trifluoromethyl-benzonitriles has been synthesized. The ability of these compounds to act as antagonists of the androgen receptor was investigated and several were found to have potent activity in vitro and in vivo. 相似文献
135.
Contact Toxicity and Repellency of the Essential Oil from Mentha haplocalyx Briq. against Lasioderma serricorne 下载免费PDF全文
Wen‐Juan Zhang Kai Yang Chun‐Xue You Cheng‐Fang Wang Zhu‐Feng Geng Yang Su Ying Wang Shu‐Shan Du Zhi‐Wei Deng 《化学与生物多样性》2015,12(5):832-839
The chemical composition of the essential oil obtained by hydrodistillation from the aerial parts of Mentha haplocalyx was investigated by GC‐FID and GC/MS analyses. In sum, 23 components, representing 92.88% of the total oil composition, were identified, and the main compounds were found to be menthol (59.71%), menthyl acetate (7.83%), limonene (6.98%), and menthone (4.44%). By bioassay‐guided fractionation (contact toxicity), three compounds were obtained from the essential oil and identified as menthol, menthyl acetate, and limonene. The essential oil and the three isolated compounds exhibited potent contact toxicity against Lasioderma serricorne adults, with LD50 values of 16.5, 7.91, 5.96, and 13.7 μg/adult, respectively. Moreover, the oil and its isolated compounds also exhibited strong repellency against L. serricorne adults. At the lower concentrations tested and at 2 h after exposure, menthol showed even significantly stronger repellency than the positive control DEET. The study revealed that the bioactivity properties of the essential oil can be attributed to the synergistic effects of its diverse major and minor components, which indicates that the M. haplocalyx oil and its isolated compounds have potential for the development as natural insecticides and/or repellents to control insects in stored grains and traditional Chinese medicinal materials. 相似文献
136.
Tellurium@Ordered Macroporous Carbon Composite and Free‐Standing Tellurium Nanowire Mat as Cathode Materials for Rechargeable Lithium–Tellurium Batteries 下载免费PDF全文
137.
138.
目的:探讨ST段抬高急性心肌梗死(ST-elevation myocardial infarction,STEMI)患者靶血管长病变(病变>25 mm)急诊经皮冠状动脉介入(percutaneous coronary intervention,PCI)治疗的临床疗效及安全性。方法:回顾性收集2009年1月-2010年6月因STEMI就诊于沈阳军区总医院并急诊行PCI处理的患者442例,以靶病变长度分为两组,即≤25 mm为短病变组(n=235)和>25mm为长病变组(n=207),均急诊行PCI治疗,分析和比较两组患者术前的基线资料、术中资料及并发症的发生情况、辅助措施(临时起搏、IABP、血栓抽吸装置)应用情况,术后30天、2年电话或临床随访,记录主要不良心血管事件(major adverse cardiac events,MACE)的发生情况。结果:与短病变组比较,长病变组吸烟者更多(81.6%vs 62.6%,P=0.000);以三支病变偏多(34.8%vs 24.7%,P=0.037);多枚支架使用率更高(1.47±0.63 vs 1.04±0.28,P=0.000),平均支架总长度显著增加(29.80±7.02 mm vs 22.95±5.58mm,P=0.000),手术成功率、术中并发症及辅助措施应用情况比较差异无统计学意义(P>0.05),30天及2年随访MACE的发生率比较差异无统计学意义(P>0.05)。结论:与急诊PCI治疗的STEMI短病变患者对比,长病变患者虽然病变复杂,多枚支架使用率高,平均支架总长度增加,但术中并发症、30天、2年内MACE与短病变患者相当,提示在以药物洗脱支架为主的介入治疗时代,急诊PCI处理STEMI靶血管长病变具有良好的疗效及安全性。 相似文献
139.
Zongyou Yang Wei Chen Zhidao Xia Yueju Liu Shaun Peggrem Tao Geng Zhaoxu Yang Han Li Bin Xu Chi Zhang James T. Triffitt Yingze Zhang 《PloS one》2015,10(5)
Delayed healing or non-union of skeletal fractures are common clinical complications. Ibandronate is a highly potent anti-catabolic reagent used for treatment of osteopenia and fracture prevention. We hypothesized that local application of ibandronate after fracture fixation may improve and sustain callus formation and therefore prevent delayed healing or non-union. This study tested the effect of local application of an ibandronate/gelatin sponge composite on osteotomy healing. A right-side distal-femoral osteotomy was created surgically, with fixation using a k-wire, in forty adult male rabbits. The animals were divided into four groups of ten animals and treated by: (i) intravenous injection of normal saline (Control); (ii) local implantation of absorbable gelatin sponge (GS); (iii) local implantation of absorbable GS containing ibandronate (IB+GS), and (iv) intravenous injection of ibandronate (IB i.v.). At two and four weeks the affected femora were harvested for X-ray photography, computed tomography (CT), biomechanical testing and histopathology. At both time-points the results showed that the calluses in both the ibandronate-treated groups, but especially in the IB+GS group, were significantly larger than in the control and GS groups. At four weeks the cross sectional area (CSA) and mechanical test results of ultimate load and energy in the IB+GS group were significantly higher than in other groups. Histological procedures showed a significant reduction in osteoclast numbers in the IB+GS and IB i.v. groups at day 14. The results indicate that local application of an ibandronate/gelatin sponge biomaterial improved early osteotomy healing after surgical fixation and suggest that such treatment may be a valuable local therapy to enhance fracture repair and potentially prevent delayed or non-union. 相似文献
140.
Ying Lyu Xueying Su Jingna Deng Shangxin Liu Liangqiang Zou Xiaojing Zhao Suning Wei Bin Geng Guoheng Xu 《PloS one》2015,10(2)
Perilipin 1 (Plin1) localizes at the surface of lipid droplets to regulate triglyceride storage and hydrolysis in adipocytes. Plin1 defect leads to low adiposity in mice and partial lipodystrophy in human. This study investigated the roles of Plin1 in adipocyte differentiation. Plin1 null (-/-) mice showed plenty of multilocular adipocytes and small unilocular adipocytes in adipose tissue, along with lack of a subpopulation of adipose progenitor cells capable of in vivo adipogenesis and along with downregulation of adipogenic pathway. Before initiation of differentiation, adipose stromal-vascular cells (SVCs) from Plin1-/- mice already accumulated numerous tiny lipid droplets, which increased in number and size during the first 12-h induction but thereafter became disappeared at day 1 of differentiation. The adipogenic signaling was dysregulated despite protein level of PPARγ was near normal in Plin1-/- SVCs like in Plin1-/- adipose tissue. Heterozygous Plin1+/- SVCs were able to develop lipid droplets, with both the number and size more than in Plin1-/- SVCs but less than in Plin1+/+ SVCs, indicating that Plin1 haploinsufficiency accounts for attenuated adipogenesis. Aberrant lipid droplet growth and differentiation of Plin1-/- SVCs were rescued by adenoviral Plin1 expression and were ameliorated by enhanced or prolonged adipogenic stimulation. Our finding suggests that Plin1 plays an important role in adipocyte differentiation and provides an insight into the pathology of partial lipodystrophy in patients with Plin1 mutation. 相似文献