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51.
莫永胜  李仕琼   《广西植物》1992,12(2):182-189
本文扼要回顾和评述了雄性生殖单位的发现、意义和研究进展,并对目前存在的问题和今后的研究进行了讨论和展望。  相似文献   
52.
细菌巨大质粒的快速检测   总被引:3,自引:0,他引:3  
本文报道了一种快速检测微生物巨大质粒的方法.该方法是通过对Eckhardt所报道的方法加以改进,使之能对根瘤菌、大肠杆菌、甚至链霉菌的大质粒进行快速检测.  相似文献   
53.
目的观察正常大鼠胃组织中肌球蛋白轻链激酶的表达及分布特点。方法取11只SD正常雄性大鼠,在饥饿状态下,处死后取胃组织。通过免疫组化染色,观察正常大鼠胃组织中MLCK的表达及分布。结果MLCK在黏膜肌层、肌层和黏膜下层血管壁平滑肌均有大量表达;在胃底腺中,MLCK主要表达于壁细胞和主细胞胞浆内。结论MLCK不仅存在于平滑肌细胞内,还分布于胃底腺壁细胞和主细胞内,可能参与胃底腺腺细胞的分泌活动。  相似文献   
54.
Proteinase-activated receptor 2 (Par2, F2rl1, also designated PAR-2 or PAR2) is prominently expressed in the intestine and has been suggested as a mediator of inflammatory, mitogenic and fibrogenic responses to injury. Mast cell proteinases and pancreatic trypsin, both of which have been shown to affect the intestinal radiation response, are the major biological activators of Par2. Conventional Sprague-Dawley rats, mast cell-deficient rats, and rats in which pancreatic exocrine secretion was blocked pharmacologically by octreotide underwent localized irradiation of a 4-cm loop of small bowel. Radiation injury was assessed 2 weeks after irradiation (early, inflammatory phase) and 26 weeks after irradiation (chronic, fibrotic phase). Par2 expression and activation were assessed by in situ hybridization and immunohistochemistry, using antibodies that distinguished between total (preactivated and activated) Par2 and preactivated Par2. Compared to unirradiated intestine, irradiated intestine exhibited increased Par2 expression, particularly in areas of myofibroblast proliferation and collagen accumulation, after both single-dose and fractionated irradiation. The majority of Par2 expressed in fibrotic areas was activated. Postirradiation Par2 overexpression was greatly attenuated in both mast cell-deficient and octreotide-treated rats. The severity of acute mucosal injury did not affect postirradiation Par2 expression. Mast cells and pancreatic proteinases may exert their fibro-proliferative effects partly through activation of Par2. Par2 may be a potential target for modulating the intestinal radiation response, particularly delayed intestinal wall fibrosis.  相似文献   
55.
Liu  Yuan  Luo  Cong  Zhang  Xiu-Juan  Lu  Xin-Xi  Yu  Hai-Xia  Xie  Xiao-Jie  Fan  Zhi-Yi  Mo  Xiao  He  Xin-Hua 《Plant Cell, Tissue and Organ Culture》2020,143(1):219-228
Plant Cell, Tissue and Organ Culture (PCTOC) - CONSTANS (CO)/CONSTANS-like (COL) genes play an important role in the photoperiodic flowering pathway. However, the functional roles of the CO/COL...  相似文献   
56.
Advances in functional genomics have led to discovery of a large group of previous uncharacterized long non-coding RNAs (IncRNAs). Emerging evidence indicates that IncRNAs may serve as master gene regulators through various mechanisms. Dysregulation of IncRNAs is often associated with a variety of human diseases including cancer. Of significant interest, recent studies suggest that IncRNAs participate in the p53 tumor suppressor regulatory network. In this review, we discuss how IncRNAs serve as p53 regulators or p53 effectors. Further characterization of these p53-associated IncRNAs in cancer will provide a better understanding of lncRNA- mediated gene regulation in the p53 pathway. As a result, IncRNAs may prove to be valuable biomarkers for cancer diagnosis or poten- tial targets for cancer therapy.  相似文献   
57.

Background  

Quantitative proteomics technologies have been developed to comprehensively identify and quantify proteins in two or more complex samples. Quantitative proteomics based on differential stable isotope labeling is one of the proteomics quantification technologies. Mass spectrometric data generated for peptide quantification are often noisy, and peak detection and definition require various smoothing filters to remove noise in order to achieve accurate peptide quantification. Many traditional smoothing filters, such as the moving average filter, Savitzky-Golay filter and Gaussian filter, have been used to reduce noise in MS peaks. However, limitations of these filtering approaches often result in inaccurate peptide quantification. Here we present the WaveletQuant program, based on wavelet theory, for better or alternative MS-based proteomic quantification.  相似文献   
58.
Changes in process performance and the nitrifying bacterial community associated with an increase of thiocyanate (SCN) loading were investigated in a pre-denitrification process treating industrial wastewater. The increased SCN loading led to the concentration of total nitrogen (TN) in the final effluent, but increasing the internal recycling ratio as an operation parameter from 2 to 5 resulted in a 21% increase in TN removal efficiency. In the aerobic reactor, we found that the Nitrosomonas europaea lineage was the predominant ammonia oxidizing bacteria (AOB) and the percentages of the AOB population within the total bacteria increased from about 4.0% to 17% with increased SCN concentration. The increase of nitrite loading seemed to change the balance between Nitrospira and Nitrobacter, resulting in the high dominance of Nitrospira over Nitrobacter. Meanwhile, a Thiobacillus thioparus was suggested to be the main microorganism responsible for the SCN biodegradation observed in the system.  相似文献   
59.
正2017年11月4日上午11时左右,在天津市北大港湿地自然保护区的万亩鱼塘(38°47′15.33″N,117°25′3.98″E,海拔3 m)观察到1只白额鹱(Calonectris leucomelas)飞过,并拍照记录。此后数日前往观察,均未能再看到此鸟。被观察到时,该白额鹱的飞行高度约60 m;当时同域空中有红嘴鸥(Chroicocephalus ridibumdus)、红嘴巨燕  相似文献   
60.
【目的】对从广西某鸭场发生呼吸道感染的11天龄樱桃谷肉鸭分离到的病毒株进行鉴定,并探索此鸭源病毒分离株的遗传变异情况。【方法】通过血凝试验、鸡胚接种实验、3?端非编码区(3'UTR)基因扩增与序列测定对分离株进行鉴定,并对该分离株的结构基因S1、E、M和N分别进行序列测定以及相似性、系统进化树分析和血清型鉴定。【结果】血凝试验为阴性,接种鸡胚盲传5代后出现侏儒胚,3?UTR基因测序结果表明为传染性支气管炎病毒(IBV)序列。该分离株S蛋白的裂解位点为RRSRR,S1、E、M和N基因与IBV毒株H120、4/91、LTD3核苷酸相似性分别为:78.6%–99.7%、85.4%–100.0%、91.6%–93.2%、86.7%–91.7%。除N基因存在点突变外,S1、E和M基因均存在氨基酸的突变、插入和(或)缺失。系统进化树分析显示,其S1基因属于4/91型,E、M和N基因均为LDT3型。血清型分析表明,该分离株的血清型不同于疫苗株H120和4/91。【结论】此鸭源病毒分离株为IBV,且该分离株的基因型与血清型均发生了变异。本研究结果暗示禽类传染性支气管炎的防控面临着更严峻的挑战。  相似文献   
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