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991.
Ruan Yun-Zhen 《植物分类学报:英文版》1988,26(6):443-449
In the classification of J. D. Hooker (1873) and of K. Schumann (1891),
the genus Prismatomeris Thw. is included in the tribe Morindeae of Rubiaceae. In the modern classifications, e. g. Bremekamp (1966), however, the taxonomic position of the genus is
still uncertain. The genus agrees with the tribe Morindeae in the downward radicle, valvate
aestivation of the corolla lobes and presence of raphides, but it differs significantly from the
latter in the free flowers, bilocular ovary and the peltate ovule attached to the upper half of
septum. Therefore, it would be more suitable that the genus is separated from the tribe Morindeae Miq., and is raised to the rank of tribe, placed in the subfamily Rubioideae based on
Bremekamp’s delimitation.
In the present paper ten character pairs of the genus and the notes on their taxonomic
value are presented and two following species are recognized:
1. P. tetrandra (Roxb.) K. Schum. is found in northern India. Its subspecies,
which is distributed in Yunnan of China and in Thailand, was previously called P. tetrandra (Roxb.) K. Schumann, and is now revised as P. tetrandra (Roxb.) K. Schum.
subsp. multiflora (Ridley) Y. Z. Ruan.
2. P. connata Y.Z. Ruan is described as a new species, that has been treated as P.
tetrandra (Roxb.) K. Schum. by previous auth rs. It is native to the subtropic region of South
China. Its tropical new subspecies, P. connata. Y. Z. Ruan subsp. hainanensis Y. Z.
Ruan, is found on Hainan Island. 相似文献
992.
Li De-gao Ruan Yun-chang 《Plant Diversity》1980,2(4):1-3
Diosgenin and Yamogehin were isolated and identified from the tubers of Discorea L. [D. parviflora Ting, D. panthaica Prain et Burk., D. coll-ettii Hook. f., D. collettii Hook. f. var. hypoglauca (Pa1ibin) Pei. et Ting ] in Yunnan. The results obtained are listed in the tables of this paper. The mixed sapogenins can obtain a better yield (48-56% ) to synthesize 3 βacetoxypregna-5, 16-dien-30-onet. 相似文献
993.
Lü Zhi-cheng 《仿生工程学报(英文版)》2006,3(2):59-62
Monolayer of polymer latex spheres was prepared at the air/water interface and deposited onto glass slides through Langmuir-Blodgett (LB) technique. Large-scale, high quality hexagonally close-packed domains were found in scanning electron microscopic pictures. Details of the monolayer-forming ability were discussed. Suitable surface characteristics of the colloidal particles, especially the hydrophilic and hydrophobic properties, are the keys for the formation of ordered monolayer films. The film can be transferred onto various kinds of substrates, even high curvature surface articles, such as fibers, decorations etc, can also be used as substrates. The advantages of this fabrication method of polymer latex spheres monolayer are fast, flexible, simple and very neat. 相似文献
994.
Yizhi Jiang Yaqiong Tang Christopher Hoover Yuji Kondo Dongping Huang Damien Restagno Bojing Shao Liang Gao J. Michael McDaniel Meixiang Zhou Robert Silasi-Mansat Samuel McGee Miao Jiang Xia Bai Florea Lupu Changgeng Ruan Jamey D. Marth Depei Wu Yue Han Lijun Xia 《Cell death and differentiation》2021,28(11):3009
The liver has recently been identified as a major organ for destruction of desialylated platelets. However, the underlying mechanism remains unclear. Kupffer cells, which are professional phagocytic cells in the liver, comprise the largest population of resident tissue macrophages in the body. Kupffer cells express a C-type lectin receptor, CLEC4F, that recognizes desialylated glycans with an unclear in vivo role in mediating platelet destruction. In this study, we generated a CLEC4F-deficient mouse model (Clec4f−/−) and found that CLEC4F was specifically expressed by Kupffer cells. Using the Clec4f−/− mice and a newly generated platelet-specific reporter mouse line, we revealed a critical role for CLEC4F on Kupffer cells in mediating destruction of desialylated platelets in the liver in vivo. Platelet clearance experiments and ultrastructural analysis revealed that desialylated platelets were phagocytized predominantly by Kupffer cells in a CLEC4F-dependent manner in mice. Collectively, these findings identify CLEC4F as a Kupffer cell receptor important for the destruction of desialylated platelets induced by bacteria-derived neuraminidases, which provide new insights into the pathogenesis of thrombocytopenia in disease conditions such as sepsis.Subject terms: Glycobiology, Cell death and immune response, Haematological diseases 相似文献
995.
Qi Lu Jun Xiong Yuan Yuan Zhanwei Ruan Yu Zhang Bo Chai Lei Li Shufang Cai Jian Xiao Yanqing Wu Peng Huang Hongyu Zhang 《International journal of biological sciences》2022,18(1):441
Traumatic brain injury (TBI) is one of the main concerns worldwide as there is still no comprehensive therapeutic intervention. Astrocytic water channel aquaporin-4 (AQP-4) system is closely related to the brain edema, water transport at blood-brain barrier (BBB) and astrocyte function in the central nervous system (CNS). Minocycline, a broad-spectrum semisynthetic tetracycline antibiotic, has shown anti-inflammation, anti-apoptotic, vascular protection and neuroprotective effects on TBI models. Here, we tried to further explore the underlying mechanism of minocycline treatment for TBI, especially the relationship of minocycline and AQP4 during TBI treatment. In present study, we observed that minocycline efficaciously reduces the elevation of AQP4 in TBI mice. Furthermore, minocycline significantly reduced neuronal apoptosis, ameliorated brain edema and BBB disruption after TBI. In addition, the expressions of tight junction protein and astrocyte morphology alteration were optimized by minocycline administration. Similar results were found after treating with TGN-020 (an inhibitor of AQP4) in TBI mice. Moreover, these effects were reversed by cyanamide (CYA) treatment, which notably upregulated AQP4 expression level in vivo. In primary cultured astrocytes, small-interfering RNA (siRNA) AQP4 treatment prevented glutamate-induced astrocyte swelling. To sum up, our study suggests that minocycline improves the functional recovery of TBI through reducing AQP4 level to optimize BBB integrity and astrocyte function, and highlights that the AQP4 may be an important therapeutic target during minocycline treating for TBI. 相似文献
996.
Yong Shao Xiao-Bo Wang Mei-Ling Zhang Yan Liu Sheng Wang Bao-Lin Zhang Min-Min Yang Ming-Hai Yang Ting Jia Tian-Chun Pu Yan Lu He Liu Zhe Xu Bo Li Ning Liu Violet Magoma Onsongo Dong-Dong Wu Cheng-Lin Zhang Jue Ruan Yan Li 《Molecular biology and evolution》2022,39(3)
The spotted hyena (Crocuta crocuta) is a large and unique terrestrial carnivore. It is a particularly fascinating species due to its distinct phenotypic traits, especially its complex social structure and scavenging lifestyle, with associated high dietary exposure to microbial pathogens. However, the underlying molecular mechanisms related to these phenotypes remain elusive. Here, we sequenced and assembled a high-quality long-read genome of the spotted hyena, with a contig N50 length of ∼13.75 Mb. Based on comparative genomics, immunoglobulin family members (e.g., IGKV4-1) showed significant adaptive duplications in the spotted hyena and striped hyena. Furthermore, immune-related genes (e.g., CD8A, LAG3, and TLR3) experienced species-specific positive selection in the spotted hyena lineage. These results suggest that immune tolerance between the spotted hyena and closely related striped hyena has undergone adaptive divergence to cope with prolonged dietary exposure to microbial pathogens from scavenging. Furthermore, we provided the potential genetic insights underlying social complexity, hinting at social behavior and cognition. Specifically, the RECNE-associated genes (e.g., UGP2 and ACTR2) in the spotted hyena genome are involved in regulation of social communication. Taken together, our genomic analyses provide molecular insights into the scavenging lifestyle and societal complexity of spotted hyenas. 相似文献
997.
同时表达多种外源基因的非复制型重组痘苗病毒的构建 总被引:13,自引:5,他引:8
利用非复制型痘苗病毒载体,构建了能同时表达乙型肝炎(乙肝)病毒SS1、麻疹病毒HA和F及白细胞介素2(IL-2)的非复制型重组痘苗病毒VIHIL2△CKSS1,及其相应的复制型重组豇轩病毒VHFIL2SS1。这两株重组病毒在CEF细胞上连续传至第25代,经Southern,两株病毒均在A24、A27间稳定整合有SS1基因,非复制型重组病毒C、K间基因稳定缺失。经RIA、ELISA及Western 相似文献
998.
城郊公路两侧主要森林类型铅含量及分布规律 总被引:31,自引:3,他引:28
对南京城郊312国道两侧主要森林类型林木不同器官中Pb含量和分布规律的研究表明,不同树种、同一树种不同器官中Pb含量有明显差异.火炬松对Pb污染的净化能力强于杉木、栎树.汽车尾气排放的Pb污染影响范围在离公路两侧100m以内,主要在40m以内范围.有林地土壤由于有林木及林下植被的覆盖,其Pb含量(尤其是表层0~20cm范围内)明显降低,说明林分可有效地降低土壤中Pb的污染程度.林木不同器官对Pb尘的吸附率在180%~281%之间,以叶片吸附能力最强;不同树种比较,以松树吸附率为高 相似文献
999.
金属硫蛋白(metalothionein,简称MT)是一类低分子量、富含半胱氨酸的蛋白质,由于1个MT分子可结合7个金属离子,因此MT分子具有很强的金属结合特性[1,2].本文一方面利用MT分子的高金属结合性能,另一方面利用苏州医学院血液研究所研制成... 相似文献
1000.
Y Wang Z S Zhang J S Ruan Y M Wang S M Ali 《Journal of industrial microbiology & biotechnology》1999,23(3):178-187
Five thousand actinomycetes were isolated from soil samples collected from rainforests in Singapore and the generic identities
of these isolates were determined by using a procedure that combined morphological, chemotaxonomic and 16S rDNA sequence-based
phylogenetic analyses. Actinomycetes belonging to a total of 36 genera were identified. The most abundant isolates are members
of Streptomyces, Micromonospora, Actinoplanes, Actinomadura, Nonomuria, Nocardia and Streptosporangium. By phylogenetic analysis of 16S rDNA sequences of our isolates together with those of known actinomycete species, we also
evaluated the species diversity of several genera including Streptomyces, Micromonospora, Nonomuria, and Actinomadura. We found that: first, the tropical isolates are present in most clades represented by known species; and second, many tropical
isolates form new clades distant from the known species, indicating the presence of unidentified taxa at both species and
genus levels. Based on these results, we conclude that actinomycete diversity in the tropical rainforest is very great and
should represent an excellent source for discovery of novel bioactive compounds.
Received 17 March 1999/ Accepted in revised form 24 June 1999 相似文献