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921.
922.
Guocai Zhong Huan Yan Haimin Wang Wenhui He Zhiyi Jing Yonghe Qi Liran Fu Zhenchao Gao Yi Huang Guangwei Xu Xiaofeng Feng Jianhua Sui Wenhui Li 《Journal of virology》2013,87(12):7176-7184
Primary Tupaia hepatocytes (PTHs) are susceptible to woolly monkey hepatitis B virus (WMHBV) infection, but the identity of the cellular receptor(s) mediating WMHBV infection of PTHs remains unclear. Recently, sodium taurocholate cotransporting polypeptide (NTCP) was identified as a functional receptor for human hepatitis B virus (HBV) infection of primary human and Tupaia hepatocytes. In this study, a synthetic pre-S1 peptide from WMHBV was found to bind specifically to cells expressing Tupaia NTCP (tsNTCP) and it efficiently blocked WMHBV entry into PTHs; silencing of tsNTCP in PTHs significantly inhibited WMHBV infection. Ectopic expression of tsNTCP rendered HepG2 cells susceptible to WMHBV infection. These data demonstrate that tsNTCP is a functional receptor for WMHBV infection of PTHs. The result also indicates that NTCP''s orthologs likely act as a common cellular receptor for all known primate hepadnaviruses. 相似文献
923.
Sung-Tae Hong Yan Jin Khikmat Anvarov Abdukhakim Khadjibaev Samin Hong Yusufjon Ahmedov Utkir Otaboev 《The Korean journal of parasitology》2013,51(3):383-385
Uzbekistan is endemic of cystic echinococcosis (CE). In order to estimate endemicity of CE, we collected data from emergency surgery due to CE in 2002-2010 and also investigated the prevalence of hydatid cysts in the liver and lungs of sheep at an abattoir in Uzbekistan from July 2009 to June 2010. In 14 emergency hospitals, 8,014 patients received surgical removal or drainage of CE during 2002-2010, and 2,966 patients were found in 2010. A total of 22,959 sheep were grossly examined of their liver and lungs, and 479 (2.1%) and 340 (1.5%) of them were positive for the cyst in the liver and lungs, respectively. Echinococcus granulosus is actively transmitted both to humans and sheep, and CE is a zoonotic disease of public health priority in Uzbekistan. 相似文献
924.
Zhechen Qi Kenneth M. Cameron Pan Li Yunpeng Zhao Shichao Chen Guangcun Chen Chengxin Fu 《Botanical journal of the Linnean Society. Linnean Society of London》2013,173(4):535-548
Smilacaceae, composed of Smilax and Heterosmilax, are a cosmopolitan family of > 200 species of mostly climbing monocots with alternate leaves characterized by reticulate venation, a pair of petiolar tendrils and usually prickly stems. Although there has been a long history of studying Smilax since Linnaeus named the genus in 1753, the phylogenetic history of this dioecious family remains unclear. Here we present results based on nuclear ribosomal internal transcribed spacer (nrITS) and plastid matK and rpl16 intron DNA sequence data from 125 taxa of Smilacaceae. Our taxon sampling covers all sections of Smilax and Heterosmilax and major distribution zones of the family; species from Ripogonaceae and Philesiaceae are used as outgroups. Our molecular analysis indicates that phylogenetic relationships largely contradict the traditional morphological classification of the family, instead showing a conspicuous geographical pattern among the species clades. The previously recognized genus Heterosmilax was found to be embedded in Smilax. Species in the family are separated into primarily New World and Old World clades, except for a single species lineage, Smilax aspera, that is sister to the remaining species of the family, but with poor statistical support. Ancestral character state reconstructions and examination of distribution patterns among the clades provide important information for future taxonomic revisions and historical biogeography of the group. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173 , 535–548. 相似文献
925.
Malleola tibetica, a new species from southeastern tropical Tibet, China, is described and illustrated. Morphologically, the new species is closely related to M. dentifera, but differs from it by having uniformly green leaves, flowers with entire lateral lobes of the lip and a basally thickened mid‐lobe, and a column that is densely cristaline‐papillose adaxially. 相似文献
926.
Fuju Tai Qi Wang Zuli Yuan Zhiheng Yuan Huiyun Li Wei Wang 《Acta Physiologiae Plantarum》2013,35(5):1555-1564
ABA, H2O2 and Ca2+ play critical roles as signals in the adaptive responses of plants to water and other stresses. They accumulate in plant cells under water and other stresses and induce changes in stress-related gene expressions. CIPKs, protein kinases associated with a calcineurin B-like calcium sensor, play a role in the regulation of stress gene expression in plants. However, it is still unclear whether ABA and H2O2 are key inducers that regulate the changes in CIPK expressions under water stress. In this study, five stress-inducible CIPKs in maize were retrieved from Database. They were designated as ZmCIPK1, 3, 8, 17 and 18, based on their homologies with known CIPK sequences. The expressions of the five ZmCIPKs in maize leaves and roots were analyzed and found to be regulated by PEG, CaCl2, ABA and H2O2 to different extents. Moreover, the effect of ABA and H2O2 on the expressions of ZmCIPKs under water stress was in an organ-dependent manner. 相似文献
927.
Tuvd Dariima Guang-Zhen Jin Eun-Jung Lee Ivan B. Wall Hae-Won Kim 《Biotechnology letters》2013,35(7):1135-1143
Osteogenesis requires close co-operation with angiogenesis to create vascularized bone tissue. In this study, an indirect co-culture model using osteoblasts (OBs), primary endothelial cells (ECs) and Matrigel interlayer was established to understand the impact of each cell type on the other. ECs synergistically enhanced osteoblastic gene expression by OBs, while OBs were capable of supporting tubule-like structures formed by ECs on Matrigel, enhancing mean tubule length from 146.5 ± 23.5 μm in ECs alone to 192 ± 28.6 μm in co-culture (p < 0.05). Similar improvements were noted in terms of tubule number. An applicability study of the co-culture model to bone tissue engineering, performed on a biopolymer fibrous membrane, showed substantially enhanced deposition of calcified nodules. These results demonstrate the efficacy of co-culture with ECs to improve osteogenesis for bone tissue engineering. 相似文献
928.
Ding Xiaotao Jiang Yuping Wang Hong Jin Haijun Zhang Hongmei Chen Chunhong Yu Jizhu 《Acta Physiologiae Plantarum》2013,35(5):1427-1438
The effects of 6-benzylaminopurine (6-BA) on plant growth, net photosynthetic rate, relative chlorophyll content, soluble protein, carbohydrates contents and antioxidant systems of cucumber (Cucumis sativus L.) under low-light environment were investigated using two different cucumber cultivars. The results showed that the weak light resulted in the remarkable decrease in plant net photosynthetic rate, relative chlorophyll content, soluble protein and carbohydrates contents, but promoted the superoxide dismutase and guaiacol peroxidase activities. However, application of 6-BA alleviated the reduction of the correlative parameters and mediated the changes of antioxidant systems. The potential mechanisms may involve the following aspects: 6-BA clearly enhanced the plants’ tolerance to low light by increasing chlorophyll content, reducing the production of superoxide radical (O 2 ·? ), and enhancing the quenching of hydrogen peroxide (H2O2), consequently alleviating the injury of photosynthetic system, and further increasing the efficiency of CO2 assimilation, producing more carbohydrates which can meet the growth need of cucumber. Meanwhile, the present study indicated that cucumber of Europe mini type (Chunqiuwang) was more tolerant to low light than HuaNan type (Huza No.3). 相似文献
929.
Rubia austrozhejiangensis Z. P. Lei, Y. Y. Zhou & R. W. Wang, a new species of Rubiaceae from China, is described and illustrated. The new species is similar to R. ovatifolia Z. Ying Zhang and R. argyi (H. Lév. & Vaniot) H. Hara ex Lauener, but differs from the former in having stems and branches cylindrical, not quadrate‐angled, long‐ovate to ovate‐lanceolate leaf blades, many‐flowered inflorescence, and smaller mericarps, 3–4 mm in diameter. In R. ovatifolia, stems and branches are quadrate‐angled, leaf blades ovate, ovate‐cordate to rounded cordate, and the inflorescences are sparsely flowered. Compared to R. argyi, the new species has cylindrical, not quadrate‐angled stems and branches, leaf blades that are long‐ovate to ovate‐lanceolate, 3–5‐veined, and slightly reflexed corolla lobes. In R. argyi, stems and branches are quadrate‐angled or winged, the corolla lobes are spreading, and the mericarps are 5–7 mm in diameter. 相似文献
930.
In‐Jin Yoon 《Ethnic and racial studies》2013,36(2):315-335
The growth of Korean immigrant entrepreneurship in Chicago is a product of three interacting factors: employment opportunities in the general labour market, resource mobilization, and business opportunity structures. Because of their language barrier and less transferable education and occupational skills in the American labour market, many Korean immigrants could not find white‐collar occupations for which they had been trained. Disadvantaged, but still strongly motivated for upward economic mobility in the United States, many of them became self‐employed business owners. Korean immigrants’ middle‐class backgrounds and their stable family structures and strong family ties helped them to realize their goal of business ownership. In addition, social networks based on kinship, friendship, church membership, and school ties provided prospective business owners with financial assistance, training, business advice, and information about business opportunities. The first business opportunities for Korean immigrants of Chicago opened in Korean ethnic markets and non‐ethnic minority markets almost simultaneously in the early 1970s. While the demand of Koreans for their cultural products created an economic niche for Korean‐oriented businesses, the export‐import trade linkage between South Korea and the United States has paved the way for the entrance of Korean businesses into minority areas. Because of different economic niches, the two types of Korean businesses developed independently. The interethnic succession of residence, which had occurred in the late 1960s and early 1970s also produced vacated business opportunities in Koreatown and black neighbourhoods, enabling Korean immigrants to enter these areas without great resistance from local businesses. After Korean immigrants had accumulated capital and experience in Korean ethnic markets and minority markets, they advanced into more capital‐intensive businesses like garment manufacturing. Korean immigrant professionals began to enter the Korean ethnic economy in the early 1980s when the foundation of the Korean ethnic economy was already established. 相似文献