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41.
本研究在初步实现水稻原生质体培养的程序化后,选用普通栽培稻P339和特种稻苏御糯选的原生质体为融合亲本,利用碘乙酸(IA)和罗丹明-6G(R-6G)这两个代谢互补抑制剂钝化处理亲本原生质体,确定了合适的抑制条件。P339用0.25mmol/L IA,苏御糯选用50μg/ml R-6G分别经30min钝化处理,通过PEG和高Ca~(2 )、高pH法诱导融合,异源融合体具有代谢互补效应,经培养得到愈伤组织17块,并进一步分化获得不同形态的再生植株12棵。移栽存活的再生植株成熟后可育,通过对这些植株的形态以及酯酶和过氧化物酶同工酶电泳的分析表明是融合后的体细胞杂种植株。 相似文献
42.
43.
对新疆蛾类标本鉴定和资料整理,共得到蛾类12科245属549种。其中种类最多的是夜蛾科Noctuidae136属364种,物种数量超过20种的分别有卷蛾科Tortricidae 24属36种,天蛾科Sphingidae 13属30种,灯蛾科Arctiidae 19属25种和木蠹蛾科Cossidae 8属25种;物种数超过10种的有尺蛾科Geometridae 13属18种,螟蛾科Pyralidae 14属17种和舟蛾科Notodontidae 8属17种;其余几个科种类均少于10种。在世界动物地理中,新疆蛾类以古北界为主,种数占到了434种(79.05%),其他动物地理区划组成类型仅115种(20.95%)。属级区系类型与种级基本一致,古北界162种,占总数的66.12%;古北界+东洋界共有58属,占23.67%,两种分布型占总数的89.79%。在中国动物地理中,新疆蛾类与蒙新区关系最为密切,共计245种(44.63%),其次是蒙新与华北共有56种(10.20%),蒙新与青藏共有52种(9.47%),其他动物区系组成较少。属级的区系类型以蒙新区为主,与同处古北界的东北区、华北区和青藏区关系最为密切。 相似文献
44.
Z. W. Wang X. Y. Li Z. L. Tang S. L. Yang Z. Z. Ying T. Fu B. Fan Y. L. Mu H. Ao K. Li 《Molecular biology reports》2010,37(7):3393-3400
F-box proteins are quite significant ubiquitin-proteasome pathway regulators in eukaryotic cells. FBXO40, a member of this large family, alters its expression pattern in muscle atrophy. Here we isolated most of the verified porcine
FBXO40 coding sequence (CDS) (2258 bp) and assigned it to the porcine chromosome 13q4.1-4.6 by using the INRA-Minnesota porcine
radiation hybrid panel, and we also explored the tissue expression distributions, which is relatively high in longissimus
dorsi muscle, heart, low in kidney, small intestine, brain, hypophysis, lymphonode, thymus, spleen, large intestine, ovary,
stomach, and undetectable in testis, liver, uterus and thyroid gland. Inferring phylogenetic tree was constructed to study
the evolutionary implications. Moreover, a HindII (HincII)-RFLP (A/C) polymorphism in 3′-untranslated region (3′-UTR) of porcine FBXO40 gene was demonstrated by sequencing and PCR-restriction fragment length polymorphism (PCR-RFLP) analysis. Statistical analysis
result of this polymorphism showed that the allele A was predominant in all detected indigenous breeds, but C in western introduced
commercial breeds. The SNP was further analyzed in our experimental pig population including Tongcheng, Landrace, Large White,
and crossbreds of Large White × (Landrace × Tongcheng) and Landrace × (Large White × Tongcheng). The association analysis
results indicated that the A/C base substitution was associate with some hematological indexes, the hemoglobin concentration
(P < 0.0001), mean corpuscular volume hemoglobin concentration (P = 0.0002) and mean corpuscular volume (P = 0.0138). 相似文献
45.
Discovery and synthesis of 6,7,8,9-tetrahydro-5H-pyrimido-[4,5-d]azepines as novel TRPV1 antagonists
Hawryluk NA Merit JE Lebsack AD Branstetter BJ Hack MD Swanson N Ao H Maher MP Bhattacharya A Wang Q Freedman JM Scott BP Wickenden AD Chaplan SR Breitenbucher JG 《Bioorganic & medicinal chemistry letters》2010,20(23):7137-7141
Utilization of a tetrahydro-pyrimdoazepine core as a bioisosteric replacement for a piperazine-urea resulted in the discovery a novel series of potent antagonists of TRPV1. The tetrahydro-pyrimdoazepines have been identified as having good in vitro and in vivo potency and acceptable physical properties. 相似文献
46.
Hongyan Han Qiang Ao Guoqiang Chen Shijie Wang Huancong Zuo 《Biotechnology letters》2010,32(4):585-591
Autologous nerve grafts are widely used in bridging critical gaps of peripheral nerves, but they remain associated with high
morbidity of the donor site and lack of full recovery. As an alternative, we have focused on chitosan nerve conduits filled
with a heparin-incorporated fibrin–fibronectin matrix serving as delivery systems for basic fibroblast growth factor (bFGF). The artificial nerve conduits were
used for repairing sciatic nerve defects of 10 mm in adult rats. Three months post-operation, the conduction velocity recovery
index (CVRI) and the muscle restoration rate (MRR) in animals of the experimental group were 32 ± 4.1 and 77.4 ± 7.9%, respectively,
which were significantly higher than those of the PBS control group (17.8 ± 1.9 and 66.7 ± 6.5%), and similar to those of
the autograft group (38.4 ± 3.9 and 81.3 ± 7.8%). These results were also consistent with the densities of regenerated axons
in the three groups, which were demonstrated by histomorphological analysis. 相似文献
47.
Liu WB Ao L Zhou ZY Cui ZH Zhou YH Yuan XY Xiang YL Cao J Liu JY 《Biochemical and biophysical research communications》2010,402(3):507-514
The epigenetic mechanisms underlying the tumorigenesis caused by polycyclic aromatic hydrocarbons and nitrosamine compounds such as 3-methylcholanthrene (MCA) and diethylnitrosamine (DEN) are currently unknown. We reported previously that dynamic changes in DNA methylation occurred during MCA/DEN-induced rat lung carcinogenesis. Here, we used the same animal model to further study the evolution of methylation alterations in tumor suppressor genes (TSGs) DAPK1, FHIT, RASSF1A, and SOCS-3. We found that none of these genes were methylated in either normal or hyperplasia tissue. However, as the severity of the cancer progressed through squamous metaplasia and dysplasia to carcinoma in situ (CIS) and infiltrating carcinoma, so methylation became more prevalent. Particularly dramatic increases in the level of methylation, the average number of methylated genes, and the incidence of concurrent methylation in three genes were observed in CIS and infiltrating carcinoma. Similar but less profound changes were seen in squamous metaplasia and dysplasia. Furthermore, methylation status was closely correlated to loss of protein expression for these genes, with protein levels markedly declining along the continuum of carcinogenesis. These results suggest that progressive CpG island hypermethylation leading to inactivation of TSGs might be a vital molecular mechanism in the pathogenesis of MCA/DEN-induced multistep rat lung carcinogenesis. 相似文献
48.
Gaoneng Shao Shaoqing Tang Ju Luo Guiai Jiao Xiangjin Wei Ao Tang Jianli Wu Jieyun Zhuang Peisong Hu 《遗传学报》2010,37(8):523-531
A residual heterozygous line(RHL)carrying a heterozygous segment between two SSR loci RM11 and RM134 on the rice chromosome 7 was selected from a set of recombinant inbred lines from the cross D50(javanica)/HB277(indica).The former parent produces much longer grains than the latter.Selfed progenies of this selection were analyzed genotypically(SSRs)and phenotypically(grain length).Grain length was discontinuously variable in the mapping populations,allowing for the placement of this QTL qGL7-2 within a~4.8 cM interval defined by RM351 and RM234.A set of new markers within this region were developed,which narrowed the QTL to a 278 kb region defined by the markers Indel1 and RM21945.This region contains 49 predicted genes.The results also suggest that the novel allele for grain length will be used for the application of marker assisted selection for the improvement of grain length. 相似文献
49.
A CXCL13-like chemokine cDNA was isolated from large yellow croaker (Pseudosciaena crocea) by expressed sequence tag (EST) analysis (LycCXCL13). The full-length cDNA of LycCXCL13 is 796 nucleotides (nt) encoding a protein of 97 amino acids (aa), with a putative molecular weight of 10.7 kDa. The deduced LycCXCL13 contains a 24-aa signal peptide and a 73-aa mature polypeptide, which possesses the typical arrangement of four cysteines as found in other known CXC chemokines (C25, C27, C52 and C68). It shares 35, 36 and 39% aa sequence identities to green puffer CXCL13-like, Atlantic salmon CXCL13 and Japanese flounder CXCL13 chemokines, and 24–29% identities to CXCL13 chemokines in mammals, respectively. Phylogenetic analysis showed that LycCXCL13 is more closely related to the CXCL13 subgroup than to any other CXC chemokine subgroups. LycCXCL13 gene was constitutively expressed in all tissues examined, except for intestine. Upon induction with poly(I:C) or inactivated trivalent bacterial vaccine, LycCXCL13 gene expression was significantly up-regulated in spleen, head kidney, heart and gills at 24 h post-injection. Real-time PCR results showed that LycCXCL13 gene expression reached peak level in spleen and head kidney at 12 h after induction by poly(I:C), while its expression increased to the highest level in head kidney at 24 h or in spleen at 48 h by bacterial vaccine. Recombinant LycCXCL13 protein produced in E. coli BL21 exhibited obvious chemotaxis to the peripheral blood leucocytes (PBLs) from large yellow croaker. These results suggest that LycCXCL13 may be involved in inflammatory responses as well as homeostatic processes in large yellow croaker. 相似文献
50.
Porous fiber-reinforced chitosan nerve conduits were fabricated from chitosan yarns and a chitosan solution by combining an
industrial braiding method with a mold casting/lyophilization technique. The conduits were permeable to molecules ranging
in molecular size from 180 Da (glucose) to 66,200 Da (BSA). The compressive load of the reinforced conduits was significantly
higher than that of a non-reinforced control conduit at equal levels of strain. The tensile strength of the reinforced conduits
was also increased from 0.41 ± 0.17 to 3.69 ± 0.64 MPa. An in vitro cytotoxicity test showed the conduits were not cytotoxic
to Neuro-2a cells. Preliminary in vivo implantation testing indicated that the conduits were compatible with the surrounding
tissue.
Aijun Wang and Qiang Ao contributed equally to this work. 相似文献