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41.
姜骋  张曦  田晴  李莉 《植物研究》2020,40(4):583-592
克隆白桦BpbHLH112基因的编码序列,并进行生物信息学分析。通过实时荧光定量PCR技术分析该基因在不同胁迫处理下的表达模式,进一步克隆了BpbHLH112基因上游1 446 bp的启动子区域,序列分析表明,该区域含有多个逆境响应、激素响应以及信号转导等相关元件,通过构建BpbHLH112启动子片段融合GUS报告基因的表达载体并进行烟草瞬时转化,分析在不同胁迫处理条件下BpbHLH112启动子驱动GUS基因表达的活性,结果表明BpbHLH112启动子的表达能够被一些逆境胁迫因子诱导,本研究结果为深入研究BpbHLH112调控白桦应对非生物胁迫作用的分子机理提供了理论依据。  相似文献   
42.
A two-year aeropalynological study performed during January 14, 1993 to December 31, 1994 in Taipei City revealed 154 different pollen taxa, with the most frequent beingBroussonetia (31.3%),Trema (15%),Bischofia (6.9%),Mallotus (6.8%),Cyathea (3.8%),Morus (3.7%),Fraxinus (2.9%) and Gramineae (2.8%), respectively. Two quantitative peaks of pollen grains appeared in March and in September in 1993, but only one peak in 1994. The dominant pollen taxa during these two peaks wereBroussonetia andMallotus. The heavy rain in February 1994 seemed to have delayed the first pollen peak to April, butBroussonetia was still the most frequent taxon. After July 1994, six typhoons brought heavy precipitation to northern Taiwan. Different weather types might have an effect on the concentration of airborne pollen grains, so that the timing of quantitative peaks was different in the two studied years. Arboreal pollen (AP), non-arboreal pollen (NAP) and fern spores (FS) constituted 81.7%, 7.7% and 7.8% of the two-year sum, respectively. AP dominated from January to June, NAP in November and fern spores in July. Native species in the Taipei Basin and trees along urban roadsides were the common sources of airborne pollen. The pollen calendar of two years in Taipei City was submitted.  相似文献   
43.
Antibody-based therapeutics targeting the inhibitory receptors PD-1, PD-L1, or CTLA-4 have shown remarkable clinical progress on several cancers. However, most patients do not benefit from these therapies. Thus, many efforts are being made to identify new immune checkpoint receptor-ligand pathways that are alternative targets for cancer immunotherapies. Nectin and nectin-like molecules are widely expressed on several types of tumor cells and play regulatory roles in T- and NK-cell functions. TIGIT, CD226, CD96 and CD112R on lymphoid cells are a group of immunoglobulin superfamily receptors that interact with Nectin and nectin-like molecules with different affinities. These receptors transmit activating or inhibitory signals upon binding their cognate ligands to the immune cells. The integrated signals formed by their complex interactions contribute to regu-lating immune-cell functions. Several clinical trials are currently evaluating the efficacy of anti-TIGIT and anti-CD112R blockades for treating patients with solid tumors. However, many questions still need to be answered in order to fully understand the dynamics and functions of these receptor networks. This review addresses the rationale behind targeting TIGIT, CD226, CD96, and CD112R to regulate T- and NK-cell functions and discusses their potential application in cancer immunotherapy.  相似文献   
44.
We use data from the European Community Household Panel to investigate the impact of body weight on wages in nine European countries. When we pool the available data across countries and years, we find that a 10% increase in the average body mass index reduces the real earnings of males and females by 3.27% and 1.86%, respectively. Since European culture, society and labour market are heterogeneous, we estimate separate regressions for Northern and Southern Europe and find that the negative impact of the body mass index on earnings is larger--and statistically significant--in the latter area.  相似文献   
45.
Spleens from W/Fu rats bearing a syngeneic progressively growing (C58NT)D tumor contain cells which can inhibit lymphoproliferative responses in a mixed lymphocyte-tumor interaction designed to demonstrate suppressor activity. Spleens from rats having rejected (C58NT)D tumors also contained suppressor cells but to a lesser degree. The growth inhibition assay, which measures inhibition of proliferation of tumor cells, was evaluated as a simple assay system to screen for suppressor cell activity. The effector cells in both assays had the same characteristics, indicating a predominant role of macrophages. Normal rat spleens were found to contain growth inhibition activity which led to the demonstration of suppressor cell activity in spleens of normal animals. Removal of suppressor cells from the spleens of immunne rats results in consistently higher lymphoproliferative responses to tumor associated antigens on the tumor cells.  相似文献   
46.
The aim of this study was to investigate the role of plant hormones, particularly the gibberellins (GAs), in the thermoperiodic regulation of stem elongation in the short day plant (SDP) Begonia x hiemalis. Effects of GAs and some GA precursors were tested on plants grown under alternating day/night temperatures (DT/NT; 12/12 h), and the effects of these temperature regimes on endogenous plant hormones were analyzed using combined gas chromatography and mass spectrometry (GC-MS).Compared with constant temperatures (19/19 °C; 21/21 °C), stem elongation was significantly inhibited by low DT/high NT (14/24 °C; 18/24 °C) and enhanced by the opposite treatments (24/14 °C; 26/17 °C). GA1 stimulated elongation of internodes and petioles while ent-kaurene, kaurenoic acid, GA12, GA19, GA20 had no significant effect. The effect of GA1 was enhanced by a simultaneous application of calcium 3,5-dioxo-4-propionylcyclohexanecarboxylate (BX-112). BX-112 inhibited internode elongation at high DT/low NT (24/14 °C) but not at the reverse temperature regime.Gibberellins A53, A19, A20, A1, A4, A9, and indoleacetic acid (IAA), were identified by GC-MS from both leaves, including the petioles, and stems of B. x hiemalis. There were no apparent relationships between elongation of internodes and petioles and endogenous contents of gibberellins A53, A19, A20, and A1. Recoveries of deuterated GA4 and GA9 were generally too low for estimation of endogenous levels of these GAs.Constant temperature resulted in more open flowers and flower buds compared to alternating DT and NT. BX-112 decreased the time to anthesis.  相似文献   
47.
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