虎刺梅愈伤组织的诱导和快速繁殖

以虎刺梅不同部位为试验材料,不同浓度6-BA、NAA进行愈伤组织的诱导和快速繁殖。结果表明,MS培养基附加6-BA 0.5 mg/L+NAA 1.0 mg/L的激素组合对花柄愈伤组织诱导效果最佳;将产生的愈伤组织团转入分化培养基中诱导不定芽,其最适分化培养基为MS附加6-BA 3.0 mg/L+NAA 0.2 mg/L;再生苗在附加6-BA 2.5 mg/L+NAA 0.5 mg/L的MS培养基上生根培养效果较好。

一种高效的复习方法——题组诱导复习法

在知识点的学习过程中，很多学生会出现这样一个现象：知识点能够达到熟记的程度，但是知识点的灵活应用能力相当差．不仅达不到举一反三，而且正反应用都考虑不周到．举了一个简单例子说明如何借助题组，达到知识点巩固的效果．

大剂量α-干扰素诱导与二期利巴韦林联合疗法在未经治疗的慢性丙肝患者中的应用:一项多中心、随机、对照试验

Objectives -To evaluate in naive patients with chronic hepatitis C 1 -the efficacy and safety of one month interferon alpha (IFN-α) induction regimen; 2-the potential virological benefit of a secondary adjunction of ribavirin among HCV-RNA negative patients after 20 weeks of IFN therapy,with or without an initial 4-week IFN induction. Material and methods -151 naive HCV-RNA positive patients presenting with biopsy-proven chronic hepatitis C and elevated ALT were randomised in a 2∶1 ratio in two arms: IFN-α3 MU thrice a week (tiw) for 24 weeks (non-induced patients); IFN-α6 MU daily for two weeks, then 3 MU daily for two weeks then 3 MU tiw for 20 weeks (induced patients). At week 24, HCV-RNA negative patients were randomised to receive in addition or not ribavirin 1-1.2 g daily for 24 additional weeks. Induction efficacy was assessed on the early viral response (EVR) defined as undetectable HCV RNA at week 4 then week 20. Ribavirin efficacy was assessed on the proportion of maintained complete response until the end of follow-up, 24 weeks after discontinuation of treatment. Data were analysed on an intent-to-treat basis. Results -Efficacy of IFN-αinduction: 104 patients were randomised to the non-induction group, 47 to the induction group. Gender, age, genotype distribution and HCV viral load at baseline did not differ significantly between the two groups. There was one treatment discontinuation because of adverse events in induced patients versus four in non-induced patients (P > 0.05). The 4 week EVR was significantly greater in induced patients in patients with HCV genotype 1, 4 or 5 (47%vs 12%, P = 0.0002) only. There was no impact of induction in patients with HCV genotype 2 or 3. Efficacy of ribavirin: at week 24, 28 and 26 HCV-RNA negative patients were randomised to addition of ribavirin or not, respectively. Patients randomised to secondary additive ribavirin were more often HCV-RNA negative at the end of follow-up than patients treated with IFN-αalone: 18/28 (64%) vs 10/26 (39%); P = 0.06. Among patients randomised to bitherapy, the relapse rate was significantly lower in patients with genotype 2 or 3 (0/12 vs 6/13, P = 0.01) and not in those with genotype 1, 4 or 5 (5/11 vs 3/6, P = 0.99). Conclusion-A 4 week IFN-αinduction significantly increases the EVR rate in patients with HCV genotype 1, 4 or 5. Late secondary adjunction of ribavirin to IFN-αfor 6 months in HCV-RNA negative patients after 6 months of IFN-αsignificantly decreases the relapse rate in patients with HCV genotype 2 or 3, but not in patients with genotypes 1, 4 or 5.

烟草品种“红花大金元”变异株的快速繁殖技术

采用烟草"红花大金元"变异植株嫩叶为外植体,进行组培快繁体系研究,结果表明:最佳愈伤组织形成和再生芽萌生的培养基是:MS+6-BA 2.0 mg/L+IAA 0.5 mg/L+蔗糖20.0 g/L;而MS+KT 0.3 mg/L+NAA 0.2 mg/L培养基对丛芽的增殖效果最佳;最佳生根培养基是1/2MS+6-BA 0.1 mg/L+NAA 0.5 mg/L,根多且壮。

Callus Induction from Mature Embryos of Maize

In this study we studied the factors influencing the callus induction from mature embryos of maize inbred lines Qi 319, Zhen 58, Chang 7 -2, Lx 9801 and 81162, such as genotype, combination of plant growth regulators, and low-temperature pretreatment. The results showed that the induction rate of Qi 319 was the highest among the four genotypes tested; combination of 4.0 mg/L 2,4-D ＋ 0.5 mg/L 6-BA was suitable for inducing callus from mature embryos; three days of 4℃ pretreatment can promote the callus induction significantly. The indices optimized in the present study are helpful for establishing genetic transformation system in maize without considering seasonal variation.

Callus induction from leaves of different paulownia species and its plantlet regeneration

The experiment was carried out on five different species of Paulownia for callus induction from leaves. MS medium was adopted as basic medium, and from different combinations of NAA and BA the suitable media were determined for callus induction, bud differentiation, and root differentiation of five different species. MS+0.5NAA+4BA, MS+0.3NAA+2BA, MS+0.5NAA+4BA, MS+0.3NAA+6BA, and MS+0.3NAA+8BA were suitable media of callus inductions of leaves, respectively, for Paulownia tomentosa, Paulownia australis, Paulownia fortunei, Paulownia elongata and P. tmentosa x P. fortunei, and MS+0.3NAA+12BA, MS+0.3NAA+12BA, MS+0.5NAA+12BA, MS+0.5NAA+12BA, and MS+0.7NAA+12BA were suitable media for bud differentiation from leaf callus respectively for above five species. The rooting media was determined as 2MS+0.1NAA, 1/2MS+0.1NAA, 1/2MS, 1/2MS+0.3NAA, and 1/2MS+0.5NAA. These results provide reference data for breeding new fine va-rieties with different kinds of Paulownia protoplasts fusions.

Effects of Four Culture Media on Callus Induction Rate of Wheat Anther

Effects of four culture media including MS, N6, C17 and K on wheat anther callus induction in vitro culture were studied. The results showed that the callus in- duction rate of four kinds of culture medium was in the order of K〉C17〉N6〉MS.

A Preliminary Study on Callus Induction and Proliferation of Cylocarya paliurus

[Objective] To carry out preliminary study on callus induction and prolifer- ation of Cylocarya pafiurus. [Method] The leaf and stem segments of Cylocarya paliurus as explants were cultured on MS, WPM and improved DKW3 mediums, added 6-BA and IBA with different concentration ratios to explore the optimum medium for callus induction and proliferation. [Result] It was found that MS ＋ 4.0 mg/L 6-BA ＋ 2.0 mg/L IBA was the optimum medium for inducing stem callus of Cylocarya pali- urus, MS ＋ 2.0 mg/L 6-BA ＋ 0.5 mg/L IBA was the optimum medium for inducing leaf explants callus of Cylocarya paliurus, and MS ＋ 1.0 mg/L 6-BA ＋ 1.0 mg/L IBA was the optimum medium for callus proliferation. 200 mg/L Vitamin C was best to inhibit Cylocarya paliurus callus from browning with the browning rate of only 5.71%. [Conclusion] This study provided some theoretical basis for the establishment of tis- sue culture and rapid propagation system and the development of molecular breed- ing study of Cylocarya paliurus.

A Genetic Transformation System for Rosa multiflora Thunb. var. cathayensis Rehd. et Wils through Callus Induction

An efficient genetic transformation system is a preparation for Rosa multi-flora Thunb. var. cathayensis Rehd. et Wils to diversify its flower color through ge-netic engineering. We firstly optimized the explants and culture conditions on callus induction, hormone concentrations and dark period of culture time on bud differentia-tions in particular, with sterilized seedlings to establish the regeneration system of R. multiflora. It showed that callus induction frequency reached 100% after the ex-plants being cultured in dark for 21 d when MS was chosen to be the initial culture medium. The bud differentiation rate was 48% after cal i being cultured under dark for 8 d on MS medium supplemented with TDZ （1.5 mg/L） and NAA （0.05 mg/L）. The cal i was used as the explants that were infected with Agrobacterium tumefa-ciens harboring a DFR-RNAi construct. The transformation rate reached as high as 50%. The establishment of a highly efficient rose gene transformation system out-lined in this report is prerequisite for genetic improvement in rose flower colors.

PDGF/BMP-2对种植体周围骨修复的作用

骨修复界面的形成是评估早期种植成功的关键。然而在自然条件下,骨修复愈合期时间为3-6个月,在体内需要涉及多种类型的细胞（包括成骨细胞、破骨细胞和各种生长因子）,通过高度协调这些生长因子来完成促进血管生成和成骨的各个阶段。骨形态发生蛋白（BMPs）属于转化生长因子β家族,和其确定的20个成员都是公认诱导组织成骨的关键信号蛋白，已广泛应用于骨折或骨缺损的治疗，其具有诱导成骨细胞增殖、分化，促进骨再生的作用。

Optimization of Callus Induction Medium for Schisandga chinensis Baill via Uniform Design

[Objective]This study was to optimize callus induction medium for Schisandga chinensis Baill.[Method]Using callus induction rate as an indicator,uniform design was employed to optimize hormone combination at poly-factors and poly-levels for callus induction from Schisandga chinensis Baill.[Results]Optimal hormone combinations depended on different explants：optimum medium for both tender leaf and petiole was MS ＋3 mg/L 6-BA,for stem segment was MS ＋3 mg/L 6-BA ＋0.6 mg/L NAA.[Conclusion]Uniform design is a time-saving and convenient method for the optimum medium for callus and yields a higher callus induction rate.

Effects of 2,4-D and 6-BA on Callus Induction and Plantlet Regeneration from Mature Embryos of Hsien Rice

[ Objective] In order to study the effects of 2,4-D and 6-BA on callus cultivation from mature embryos of hsien rice. [ Method] 2,4-D and 6-BA were set at different concentrations in callus induction and differentiation mediums to study their effects on callus induction, seedling formation and regenerated seedlings rooting. [ Result] In the callus induction medium treated with 0.5 mg/L 2,4-D, the callus induction effects on the varieties like Jiayu 948, Yanghui 559, Yangxian 6547, Zhong＇erruanzhan, Minghui 86, Guanghui 998 and Zunxian 3 were the best; If 0.2 mg/L 6-BA was added into the callus induction medium containing the optimum level of 2,4-D, there was no obvious effect on induction rate of callus, but the differentiation and seedling of callus were inhibited; If the concentration of 6-BA was reduced appropriately in the differentiation medium, the seedling rate of callus would be not only no decreased but increased, meanwhile the quality of regenerated plants would be improved. [ Conclusion] The study results provided some references for the reasonable uses of 2,4-D and 6-BA in callus culture of hsien rice.

Differences in Primary Callus Induction among Different Anthurium andraeanum Varieties

[Objective] This research aimed to optimize continuously the highly efficient regeneration system of Anthurium andraeanum. [Method] The leaves and petioles of four A. andraeanum varieties were used as explants to investigate the differences in primary callus induction among different A. andraeanum varieties. [Result]The callus formation capacity of SAM and SST was stronger than that of SDM and SHG. Among the four varieties, the leaf regeneration capacity of SAM, SDM and SHG was stronger than the corresponding petiole regeneration capacity. However,the petiole regeneration capacity of SST was stronger. The optimum medium for petiole callus induction of SST was 1/2 MS ＋ TDZ 4.0 mg/L ＋ 2, 4-D 0.2 mg/L with induction rate of 87.5%; the optimum medium for leaf callus induction of SAM was 1/2 MS ＋ TDZ 2.0 mg/L ＋ 2, 4-D 0.2 mg/L with induction rate more than90%; the optimum medium for leaf callus induction of SDM and SHG was all 1/2MS ＋ ZT 2.0 mg/L ＋ 2, 4-D 0.2 mg/L with induction rates of 59.34% and 79.63%,respectively. [Conclusion] In addition to variety differences, the differences in differentiation ability among different types of calluses should be also taken into account in the establishment and optimization of tissue culture and rapid propagation technology system of A. andraeanum.

Research on Callus Induction from Coleoptile Explants of Amorphophallus

[Objective] The aim was to explore the ways of callus induction and the effect that different culture condition exerted on the callus induction from coleoptile explants of Amorphophallus. [Method] The test used konjac coleoptile as materials and designed four hormones, including 6-BA, NAA, KT and 2, 4-D, grouping 8 treat- ments to conduct statistics on callus induction in different test conditions. [Result] The result showed that multi-location generation and polymorphism was the impor- tant feature of callus induction from coleoptile explants of Amorphophallus; culture condition had significant influence on callus induction from coleoptile explants （P〈 0.01）. [Conclusion] It reached the best effect of callus induction when the culture condition was MS ＋ 1.0 mg/L 6-BA ＋ 2.0 mg/L NAA or MS ＋ 1.0 mg/LKT ＋ 2.0 mg/L 2, 4-D.

Isolation of a Genomic DNA for Gastrodia Antifungal Protein and Analyses of Its Promoter in Transgenic Tobacco

A genomic DNA containing 5'-upstream region and complete open reading frame of a Gastrodia antifungal protein was isolated by screening of a genomic library from Gastrodia elata B1. To investigate the promoter activity, the 5'-flanking region - 1 157 lip upstream from the putative transcription start site was fused to the coding sequence of beta-glucuronidase (GUS) gene and transformed into Nicotiana tabacum. The strongest GUS activity was detected in the roots of transgenic tobacco, followed by stems. The leaves only showed a low GUS activity. Furthermore, the promoter established inducible expression pattern in transgenic tobacco upon fungus Trichoderma viride inoculation and jasmonic acid and salicylic acid treatments.

Effects of Six Kinds of Fungal Elicitors on Growth of Dendrobium hybrida cultivar ‘088' Tissue Culture Seedlings

To optimize the technique of rapid propagation of Dendrobium hybrida seedlings and to explore a hormone-free tissue culture method for D.hybrida,six kinds of mycorrhizal fungi which were isolated from the wild orchids were made into fungal elicitors.These fungal elicitors were added into the DE medium with concentrations of 40,60 and 80 ml/L,respectively.After a 90-d culturing,the effects of fungal elicitors on the growth of D.hybrida cultivar ‘088＇ tissue culture seedlings were studied.The results showed that treatment 13（T13） extremely significantly increased the fresh weight,but other treatment groups had no significant effects.In addition,T1,T5,T9,T11 and T13 extremely significantly influenced the contents of chlorophyll a and chlorophyll a ＋ b.However,T1 and T11 had extremely significantly effect on the content of chlorophyll b.Combining the effects on fresh weight and chlorophyll content,it could be concluded T13（40 ml/L of Y05） has promoting effects on the growth of D.hybrida tissue culture seedlings.

Induced Expression of Cytochrome P450 CYP305 B1V1 Gene in Different Tissues of Wild Mulberry Silkworm(Bombyx mandarina)

[ Objective] The aim of this study was to investigate effects of various inducers on the expression of cytochrome P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm. [ Method] Referring to the mRNA sequence of CYP305 B1 V1 Gene published in GenBank for wild mulberry silkworm, one pair of primers was designed, and the expression of cytochrome P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm treated by NaF, rutin, cypermethrin and ecdysone was also analyzed by the semi - quantitative RT - PCR. Furthermore, homology comparison and phylogenetic analysis for amino acid sequences of this gene were studied. [ Result] Rutin, cypermethrin and NaF had effects on the expression of P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm, while ecdysone had no significant effect. Homology comparison for amino acids indicated that the amino acid sequence of this gene was the most similar to that of CYP305 B1 gene in Bombyx mori with 100% amino acid identity, and highly similar to those of Tribolium casmneum CYP305A1, Apis mellifera CYP305A1, Drosophi- la melanogaster CYP305A1, Anopheles gambiae CYP305A2and Culex pipiens quinquefasciatus CYP2LI. [ Conclusion] CYP305 B1 V1 Gene of wild mulberry silkworm is likely to mainly take part in the metabolism of exogenous compounds, which is of great significance for revealing the function of cytochrome P450 and the metabolic mechanism of different drugs.

Construction of a Tapetum-Specific and Tetracycline-Inducible System

A regulated gene expression system would offer the unique opportunity to study the gene physiological functions at different developmental stages. For realizing gene special expression in plant anther at given time, we constructed a new system that combined tetracycline- inducible elements with TA29 promoter, a tapetum-specific promoter of tobacco. The system was tested in transient GUS assay system by electroporation (gene gun) transformation of tobacco ( Nicotiana tabacum L. cv. Winsconsin 38) anther. In the absence of tetracycline as the inducer, no GUS activity was detected. However, strong GUS expression was observed in tapetum. tissue upon tetracycline induction, and little GUS activity was found outside the tapetum. Our results suggested that gene expression can be restricted to a specific tissue at the given time under the control of this new system, and this system would be a very useful tool for both basic plant biology research and biotechnological applications.

In situ synthesis of Ti^(3+) self-doped mesoporous TiO_2 as a durable photocatalyst for environmental remediation

This study developed a facile approach for in situ synthesis of a Ti3＋ self-doped mesoporous TiO 2photocatalyst by an evaporation-induced self-assembly method using TiC l3,water,and F127 as the titanium precursor,solvent,and soft template agent,respectively. The as-prepared samples were investigated by X-ray diffraction,N2 adsorption-desorption measurements,ultraviolet-visible diffuse reflectance spectroscopy,electron paramagnetic resonance,and transmission electron microscopy. The influence of different reaction parameters such as the dosage of F127 and calcination temperature on the photocatalytic performance of the resulting products was evaluated. The optimized product exhibited high photocatalytic activity and stability in the oxidation of nitric oxide in air and photocatalytic degradation of methylene blue. The excellent photocatalytic performance of the Ti3＋ self-doped mesoporous TiO 2 photocatalyst is attributed to the cooperation between the mesoporous structure and self-doped Ti3＋ enhancing light absorption and effectively suppressing the recombination of photogenerated electrons and holes.

Optimization of the Callus Induction System of Chenopodium quinoa Willd

Callus induction effects of nine varieties of Chenopodium quinoa Willd. were compared by taking stem segments and cotyledons of C. quinoa as the ex- plants. At the same time, callus JnductJon of stem segments was optimized, as well as the callus proliferation system. Research results showed that the optimal explant for callus induction was stem segment. The average callus induction rate of nine varieties reached 90% in culture medium MS ＋ 0.5 mg/L 2, 4-D. In the callus opti- mization test, treatment VI （MS ＋ 0.5 mg/L 2, 4-D ＋ 0.5 mg/L KT ＋ 0.5 mg/L NAA） and treatment II （MS ＋ 0.5 mg/L 2, 4-D） had close induction rate, but the callus morphology was greatly different. The latter had loose, glossy and yellowish white calluses. Therefore, culture medium MS ＋ 0.5 mg/L 2, 4-D was the optimal for callus induction. And using 2, 4-D together with KT and NAA could significantly increase the proliferation rate of calluses.