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951.
Kaimian Li Wenli Zhu Kang Zeng Zhenwen Zhang Jianqiu Ye Wenjun Ou Samrina Rehman Bruria Heuer Songbi Chen 《Proteome science》2010,8(1):10
Background
Proteomics is increasingly becoming an important tool for the study of many different aspects of plant functions, such as investigating the molecular processes underlying in plant physiology, development, differentiation and their interaction with the environments. To investigate the cassava (Manihot esculenta Crantz) proteome, we extracted proteins from somatic embryos, plantlets and tuberous roots of cultivar SC8 and separated them by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). 相似文献952.
So-Young Bang Tae-Un Han Chan-Bum Choi Yoon-Kyoung Sung Sang-Cheol Bae Changwon Kang 《Arthritis research & therapy》2010,12(3):R115
Introduction
Anti-cyclic citrullinated peptide autoantibodies (anti-CCP) are the most specific serologic marker for rheumatoid arthritis (RA). Genetic polymorphisms in a citrullinating (or deiminating) enzyme, peptidyl arginine deiminase type IV (PADI4) have been reproducibly associated with RA susceptibility in several populations. We investigated whether PADI4 polymorphisms contribute to anti-CCP-negative as well as -positive RA, whether they influence disease severity (erosive joint status), and whether they interact with two major risk factors for RA, Human Leukocyte Antigen-DRB1 (HLA-DRB1) shared epitope (SE) alleles and smoking, depending on anti-CCP and erosive joint status. 相似文献953.
草原沙漠化过程中植物叶面积的变化及其与土壤因子的关系 总被引:2,自引:0,他引:2
在自然状态下,对沙质草原沙漠化过程中主要植物叶面积变化及其与土壤因子的关系进行了研究。结果表明:随着沙漠化加剧,羊草和糙隐子草的比叶面积在沙漠化初期(梯度Ⅰ)下降显著(P0.01),菊叶萎陵菜和冰草的比叶面积在沙漠化后期(梯度Ⅲ)下降显著(P0.05),寸草苔比叶面积下降不显著(P0.05),冷蒿比叶面积从沙漠化中、后期开始显著增加(P0.05),扁蓿豆比叶面积从沙漠化初期开始显著增大(P0.01);羊草、糙隐子草和冷蒿的叶面积指数总体上呈显著下降趋势(P0.01),扁蓿豆叶面积指数显著增加(P0.01);羊草、糙隐子草叶面积指数与土壤粘粒、C、N含量、土壤含水量呈显著正相关(P0.01),与土壤C/N比呈显著负相关(P0.01);冷蒿和扁蓿豆叶面积指数与土壤因子的相关性和上述二者正好相反(P0.05);在叶面积指数与土壤因子线性拟合中,糙隐子草叶面积指数与土壤C/N拟合最高(R2=1),其次是羊草叶面积指数与土壤含水量的拟合(R2=0.992),扁蓿豆叶面积指数与土壤C/N拟合最低(R2=0.268)。土壤C/N是影响草原沙漠化过程中共有种叶面积的关键因子(P0.05),其影响大小为糙隐子草羊草冷蒿扁蓿豆。 相似文献
954.
Inja Lim Jihyun Yun Jung‐Ha Kim Young‐Ku Kang Nari Kim Jin Han Hyoweon Bang Jae‐Hong Ko 《Birth defects research. Part B, Developmental and reproductive toxicology》2010,89(3):201-206
BACKGROUND: This study was conducted to evaluate the occurrence and fate of fetal lumbar rib induced by Scutellariae radix (SR) in rats. METHODS: Water extracts of SR were orally administered to pregnant rats from day 7 to day 17 of gestation at a dose of 186 mg/kg/day, equivalent to 25 g/kg of starting material, representing a 100‐fold increase over typical human intake level. RESULTS: The incidence of fetal lumbar rib in the SR‐treated group was increased on gestational day 20 and then decreased on postnatal day 50. The weight of fetuses in the SR‐treated group tended to be less than that in the control group. Alkaline phosphatase in SR‐treated dams was increased on gestational day 20, but was decreased on postnatal day 50. There were no significant differences between the vehicle control and SR‐treated groups in maternal body weight, embryological, histopathological, hematological, and serum biochemical changes. CONCLUSIONS: The present data suggest that the appearance of lumbar rib induced by SR is a transient fetal variation rather than teratogenicity or maternal toxicity. Birth Defects Res (Part B) 89:201–206, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
955.
Implantation of polymer scaffolds seeded with neural stem cells in a canine spinal cord injury model
956.
957.
958.
AIMS: Skim milk agar was developed to investigate extracellular cell-bound proteinase in yogurt cultures, Streptococcus thermophilus and Lactobacillus bulgaricus. METHODS AND RESULTS: The Lact. bulgaricus cultures produced more extracellular cell-bound proteinase than did Strep. thermophilus cultures. Strong positive correlations between the size of the exopolysaccharide (EPS) layer and extracellular cell-bound proteinase were found for both Streptococcus and Lactobacillus cultures. CONCLUSION: Strong positive linear relationships existed between the EPS size and colony size and the diameter of clear zone and colony size for Streptococcus cultures, whereas weak positive linear relationships were observed for Lactobacillus cultures. SIGNIFICANCE AND IMPACT OF THE STUDY: These data are useful to validate the relationship between extracellular proteinase and the EPS size of LAB. Also, a convenient medium to detect the presence of extracellular cell-bound proteinase of LAB is valuable for dairy industries. 相似文献
959.
Jiang J Li J Xu Y Han Y Bai Y Zhou G Lou Y Xu Z Chong K 《Plant, cell & environment》2007,30(6):690-699
Jasmonic acid (JA) is a well-known defence hormone, but its biological function and mechanism in rice root development are less understood. Here, we describe a JA-induced putative receptor-like protein (OsRLK, AAL87185) functioning in root development in rice. RNA in situ hybridization revealed that the gene was expressed largely in roots, and a fusion protein showed its localization on the plasma membrane. The primary roots in RNAi transgenic rice plants meandered and curled more easily than wild-type (WT) roots under JA treatment. Thus, this gene was renamed Oryza sativa root meander curling (OsRMC). The transgenic primary roots were shorter, the number of adventitious roots increased and the number of lateral roots decreased as compared to the WT. As well, the second sheath was reduced in length. Growth of both primary roots and second sheaths was sensitive to JA treatment. No significant change of JA level appeared in the roots between the transgenic rice line and WT. Expression of RSOsPR10, involved in the JA signalling pathway, was induced in transgenic rice. Western blotting revealed OsRMC induced by JA. Our results suggest that OsRMC of the DUF26 subfamily involved in JA signal transduction mediates root development and negatively regulates root curling in rice. 相似文献
960.
A trypsin inhibitor was isolated from Cassia obtusifolia by ammonium sulfate precipitation, Sepharose 4B-trypsin affinity and Sephadex G-75 chromatography. The inhibitor consisted
of a single polypeptide chain with a molecular mass of 19, 812.55 Da. It was stable from pH 2 to 12 for 24 h, whereas it was
unstable either above 70°C for 10 min or under reduced conditions. The inhibitor, which inhibited trypsin activity with an
apparent Ki of 0.3 μM, had one reactive site involving a lysine residue. The native inhibitor was resistant to pepsin digestion, whereas
the heated inhibitor produced 40% degree of susceptibility. The disulfide linkage and lysine residue were important in maintaining
its conformation. Partial amino acid sequence of the purified protein showed a high degree of homology with various members
of the Kunitz inhibitor family. Moreover, the inhibitor showed significant inhibitory activity against trypsin-like proteases
present in the larval midgut on Pieris rapae and could suppress the growth of larvae. 相似文献