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21.
On Datil [Turner] Island in the Gulf of California, we rediscovered a population of Neotoma varia, previously thought to be extinct. We captured 5 specimens: 1 was kept as a voucher, and 4 were examined and released. Analysis of previous surveys indicates that N. varia is not common on the island and occupies a very restricted range. Recolectamos especímenes de Neotoma varia de la Isla Dátil en el Golfo de California, una población anteriormente considerada ya extinta. De los cinco especímenes que recolectamos, cuatro se pusieron en libertad. El análisis de muestreos previos indica que N. varia no es común en la isla y que tiene una distribución muy limitada. 相似文献
22.
Biased binding of class IA phosphatidyl inositol 3-kinase subunits to inducible costimulator (CD278)
Acosta YY Zafra MP Ojeda G Bernardone IS Dianzani U Portolés P Rojo JM 《Cellular and molecular life sciences : CMLS》2011,68(18):3065-3079
To better understand T lymphocyte costimulation by inducible costimulator (ICOS; H4; CD278), we analyzed proteins binding
to ICOS peptides phosphorylated at the Y191MFM motif. Phosphorylated ICOS binds class IA phosphatidyl inositol 3-kinase (PI3-K) p85α, p50-55α and p85β regulatory subunits
and p110α, p110δ and p110β catalytic subunits. Intriguingly, T cells expressed high levels of both p110α or p110δ catalytic
subunits, yet ICOS peptides, cell surface ICOS or PI3-kinase class IA regulatory subunits preferentially coprecipitated p110α
catalytic subunits. Silencing p110α or p110δ partially inhibited Akt/PKB activation induced by anti-CD3 plus anti-ICOS antibodies.
However, silencing p110α enhanced and silencing p110δ inhibited Erk activation. Both p110α- and p110δ-specific inhibitors
blocked cytokine secretion induced by TCR/CD3 activation with or without ICOS costimulus, but only p110α inhibitors blocked
ICOS-induced cell elongation. Thus, p110α and p110δ are essential to optimal T cell activation, but their abundance and activity
differentially tune up distinct ICOS signaling pathways. 相似文献
23.
基于8根混凝土倒T形叠合梁受弯试验,研究了钢筋钢纤维自应力混凝土做加固材料层二次浇注到待加固混凝土T形梁,从而形成的叠合梁在负弯矩区的抗裂性能.试验结果表明,仅占叠合梁高13.9%的叠合层将梁的开裂弯矩提高44.9%.同时根据已有理论模型,推导了自应力混凝土叠合T梁后加自应力的求法和负弯矩区正截面抗裂计算公式,其计算结果与试验结果比较吻合. 相似文献
24.
采用射频磁控溅射技术在聚酰亚胺柔性衬底上制备硅基薄膜太阳能电池用铝背电板,研究了不同溅射功率和工作气压条件对铝电极薄膜性能的影响.利用原子力显微镜分析表征了薄膜的表面形貌和粗糙度,薄膜的电学性能和光学性能分别采用四探针测量仪和紫外可见近红外分光光度计进行分析表征.测试结果表明:随着溅射功率的增加,薄膜表面均方根粗糙度迅... 相似文献