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71.
双抗双高夏大豆种质鲁99-2的选育 总被引:1,自引:2,他引:1
优良种质创新是大豆新品种选育的关键。经过近20年的中间种质创新、亲本筛选、抗性选育、鉴定和品质检验等研究,育成了双抗双高的夏大豆优良种质鲁99-2。其对大豆胞囊线虫1、3、5号生理小种的抗性均为1级;对大豆花叶病毒y6株系的抗性也为1级;籽粒脂肪含量平均为22.09%,高值为22.67%;蛋白质含量平均为43.29%,高值为45.0%;蛋白质和脂肪合计含量平均为65.38%,高值达66.40%。鲁99-2的育成说明创造和利用优良种质、选择适宜的杂交亲本和采用有效的选育方法等对大豆育种至关重要。 相似文献
72.
One of the important steps in the application of biomass to producing sugars, which can be converted into bio-ethanol and other valuable chemicals by fermentation, is to hydrolyze the biomass components by sulfuric acid. It was reported that such a hydrolysis entailed the generation of acetic acid, which has been recognized as a key impurity to be surely removed from the biomass hydrolyzate for ensuring high fermentability of the hydrolyzed sugars. Regarding such a removal task, there has been a previous application of a simulated moving bed (SMB) process based on the Dowex99 adsorbent, whose performance, however, was limited by low selectivity between acetic acid and sugars. To overcome such a limitation, another adsorbent alternative to Dowex99 was searched in this study. It was found that Amberchrom-CG161C allowed higher selectivity between acetic acid and sugars than Dowex99. To investigate the relative superiority of Amberchrom-CG161C over Dowex99 as the adsorbent of an SMB process for removing acetic acid from the biomass hydrolyzate, the two SMB processes based on Amberchrom-CG161C and Dowex99 were optimized using the SMB optimization tool based on standing wave design (SWD) method. The optimization results revealed that the Amberchrom-CG161C SMB outperformed the Dowex99 SMB by a wide margin. 相似文献
73.
Guillaume Luxardi Brian Reid Fernando Ferreira Pauline Maillard Min Zhao 《Journal of visualized experiments : JoVE》2015,(99)
Cells from animals, plants and single cells are enclosed by a barrier called the cell membrane that separates the cytoplasm from the outside. Cell layers such as epithelia also form a barrier that separates the inside from the outside or different compartments of multicellular organisms. A key feature of these barriers is the differential distribution of ions across cell membranes or cell layers. Two properties allow this distribution: 1) membranes and epithelia display selective permeability to specific ions; 2) ions are transported through pumps across cell membranes and cell layers. These properties play crucial roles in maintaining tissue physiology and act as signaling cues after damage, during repair, or under pathological condition. The ion-selective self-referencing microelectrode allows measurements of specific fluxes of ions such as calcium, potassium or sodium at single cell and tissue levels. The microelectrode contains an ionophore cocktail which is selectively permeable to a specific ion. The internal filling solution contains a set concentration of the ion of interest. The electric potential of the microelectrode is determined by the outside concentration of the ion. As the ion concentration varies, the potential of the microelectrode changes as a function of the log of the ion activity. When moved back and forth near a source or sink of the ion (i.e. in a concentration gradient due to ion flux) the microelectrode potential fluctuates at an amplitude proportional to the ion flux/gradient. The amplifier amplifies the microelectrode signal and the output is recorded on computer. The ion flux can then be calculated by Fick’s law of diffusion using the electrode potential fluctuation, the excursion of microelectrode, and other parameters such as the specific ion mobility. In this paper, we describe in detail the methodology to measure extracellular ion fluxes using the ion-selective self-referencing microelectrode and present some representative results. 相似文献
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监测具有潜在威胁的小麦秆锈病病原菌小种动态并分析其毒力谱变化,是培育抗病品种不可或缺的基础工作。在小麦秆锈病鲜有发生的情况下,于2012–2013年获得小麦田间秆锈病标样11份和经有性生殖过程的禾柄锈菌小麦专化型菌样22份。上述菌样经过分离、纯化,得到了53个单孢子堆菌株。利用国内最新采用的禾柄锈菌小麦专化型小种与毒力鉴别寄主体系进行分析,鉴定出13个生理小种,其中34C3RTGQM和34Oro II-MRGQM为优势小种,出现频率均为13.2%,首次发现了对Sr5+Sr11具有联合毒力的6个新小种,其出现频率处在1.9%–13.2%范围内。同时测定出Sr9e、Sr26、Sr31、Sr33、Sr37、Sr38、Sr47和Sr Tt3等8个抗秆锈病单基因对全部供试菌株表现抗病,余下40个单基因系则分别表现对1个以上至全部菌株感病。结论:(1)首次报道了6个对Sr5+Sr11具有危险性的联合毒力谱的新小种类型,这类毒力类型应当被密切关注;(2)明确了当前完全有效的8个抗秆锈病基因和其他部分有效的抗病基因;(3)初步说明了有性循环菌株与无性循环菌株在毒力结构上存在差异。 相似文献
76.
《Endocrine practice》2021,27(12):1193-1198
ObjectiveWe aimed to find and compare the efficacy of ultrasonography (US), technetium-99m methoxyisobutylisonitrile parathyroid scintigraphy (MIBI-S), and single-photon emission computed tomography–computed tomography (SPECT-CT) in detecting the localization of parathyroid adenomas in patients with primary hyperparathyroidism.MethodsIn total, 348 patients were included in this study. Preoperative parathyroid imaging with US, MIBI-S, and SPECT-CT was evaluated and compared with operative findings. The results of the imaging methods were compared with pathology and operation reports.ResultsIn 318 patients (91.3%), one of the imaging methods was able to localize the lesion correctly. US detected the localization of the parathyroid lesions correctly in 268 patients (77%), whereas SPECT-CT and MIBI-S were correct in 254 (73%) and 209 (60%) patients, respectively. There was a statistically significant relationship between the parathyroid hormone (PTH) level and 3 imaging methods’ success rates (P < .05). The PTH cut-off value, which best determined the correct localization, was 152.5 pg/mL for US, 143 pg/mL for MIBI-S, and 143 pg/mL for SPECT-CT. It was observed that the correct localization rate for parathyroid lesions increased with higher PTH levels.ConclusionIn our study population, US was more successful, in most cases, than other imaging methods in localizing parathyroid lesions but SPECT-CT was more accurate in localizing mediastinal lesions. In addition, it was found that preoperative PTH levels affect the accuracy of imaging methods. 相似文献
77.
Xiansheng?Zhang Zaixin?Liu Qizu?Zhao Huiyun?Chang Qingge?XieEmail author 《中国科学C辑(英文版)》2004,47(1):74-81
The complete nucleotide sequence of genomic RNA of foot and mouth disease virus (FMDV) strain China/99 from infected bovine
tongue epithelium is presented. The nucleotide sequence extending from the 5’ end of the genomic RNA to the 5’ end of poly
(A) tail contains 8173 nucleotides (nt). Its open reading frame, which encodes a single polypeptide of 2332 amino acids, encompasses
6999 nt starting from the initiation codon AUG and terminating at the UAA codon 93 bases upstream from the 5’ end of poly
(A) tract. The 5’ untranslated region (UTR) is composed of 1081nt. The consensus of the 1d gene of FMDV strain China/99 compared with that of UKG/6/2001, UKG/12/2001, China/99HN4 and China/3/Tibet is over 97%. The
result showed the stains belong to the members of the Pan-Asia family. There is a remarkable differentiation in the function-unknown
(FUR), p2 and p3 regions between FMDV isolates from infected cattle and swine, especially in 3a gene. No deletion was found in genes /, 1a, 1b, 2a, 2c, 3b, and 3d. These genes might be indispensable to the surviving of FMDV. The secondary structures of small (S) fragments, FUR
and an internal ribosome entry site can be classified into three types, and the S fragment and 3’ UTR of the positive-sense
RNA fold into stem-loop structures similar to the shape of clover. 相似文献
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79.
A. Bourdon M.-C. Eberlé-PouzeratteS. Guillemard F. PortalesF. Quenet P. FaurousJ.-C. Artus 《Médecine Nucléaire》2011,35(4):232-238
Nearly 50 % of patients with colorectal cancer (CRC) develop liver metastases (LM) during their disease. Only 10 % of these patients are candidates for an initial surgical resection. Compared to systemic chemotherapy alone, intra-arterial hepatic chemotherapy showed a benefit in overall survival in patients with unresectable LM. This treatment requires surgical or endovascular introduction of an intra-arterial hepatic catheter (IAHC). A precise vascular assessment is necessary due to the frequency of anatomic variations of hepatic arterial vasculature. Complications of intra-arterial hepatic chemotherapy are related to both IAHC and chemotherapy. 99mTc-MAA hepatic perfusion scanning plays a key role before treatment initiation and during follow-up. Moreover, intra-hepatic distribution of tracer can be analysed and objectify a possible extra-hepatic spread that may lead to increased toxicity and/or less effective treatment. The different protocols, the place of 99mTc-MAA scanning compared with other imaging techniques, or frequency of checks are still debated. A literature review is presented, illustrated with some cases of normal and pathological liver perfusion scans from the department of Nuclear Medicine, Val d’Aurelle Regional Cancer Center, Montpellier. 相似文献
80.
Wen-Yi Chang Hao-Wen Kao Hsin-Ell Wang Jenn-Tzong Chen Wuu-Jyh Lin Shyh-Jen Wang Chuan-Lin Chen 《Bioorganic & medicinal chemistry letters》2013,23(23):6486-6491
Two galactose derivatives, a monovalent 99mTc-MAMA-MGal galactoside and a divalent 99mTc-MAMA-DGal galactoside, were synthesized and radiolabeled in high radiochemical purity (>98%). Dynamic microSPECT imaging and biodistribution study of two traces in normal and liver fibrosis mice showed that the 99mTc-MAMA-DGal revealed higher specific binding to asialoglycoprotein receptors in liver and then rapidly excreted via both hepatobiliary system and renal clearance. The results suggest that 99mTc-MAMA-DGal may be used as SPECT probes for noninvasive evaluation of asialoglycoprotein receptor-related liver dysfunction. 相似文献