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91.
Randall W. Myster 《Plant Ecology》1994,114(2):169-174
Because the fate of seeds is critical to understanding the invasion of old fields by trees, and plant litter is an important component defining the old field microsite of dispersed seeds, I investigated the effects of litter type (Solidago spp./goldenrod,Quercus spp./oak, mixed) and litter amount (100–800 g/m2) on tree seed germination and seedling emergence. I found that at all densities bothSolidago andQuercus litter greatly reduced emergence of the small-seeded, bird-dispersed species,Juniperus virginiana andCornus florida. For one of the large-seeded, mammal-dispersed species,Carya tomentosa, high densitySolidago litter and high density mixed litter treatments reduced emergence. For the other large-seeded species,Quercus rubra, the high density mixed litter treatment and all levels ofSolidago litter reduced emergence.Quercus seedlings emerged twice as often as the other three species in control pots without litter.Carya emerged before the other species but the high density oak treatment delayed the expansion of its cotyledons. My results suggest that litter may contribute to the slow rate of tree invasion and the low probability of tree establishment in old fields. However, old field litter studies taken together point to the difficulty in drawing general conclusions about any net effect of litter on old field tree establishment. 相似文献
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94.
记述采自内蒙古自治区大青山地区的狼蛛科Lycosidae豹蛛属Pardosa一新种:大青山豹蛛Pardosa daqing shanica sp.nov. 相似文献
95.
报道了我国园蛛科7新种,即:云南园蛛Araneus yunnanensis、景洪金蛛Argiopejing hongensis、长垂驼蛛Cyphalonolus elongalus、石门壮头蛛Chorizopes shimenensis、勐海曲腹蛛Cyrlarachne menghaiensis 、文山肥蛛Larinia wenshanensis 和十字亮腹蛛Singa cruciformis。 相似文献
96.
Corine Vernet Joëlle Boretto Marie-Geneviève Mattéi Masahide Takahashi Lucinda J. W. Jack Ian H. Mather Sylvie Rouquier Pierre Pontarotti 《Journal of molecular evolution》1993,37(6):600-612
Summary During a search for novel coding sequences within the human MHC class I region (chromosome 6p21.3), we found an exon (named B30-2) coding for a 166-amino-acid peptide which is very similar to the C-terminal domain of several coding sequences: human 52-kD Sjögren's syndrome nuclear antigen A/Ro (SS-A/Ro) and ret finger protein (RFP), Xenopus nuclear factor 7 (XNF7), and bovine butyrophilin. The first three of these proteins share similarities over the whole length of the molecule whereas butyrophilin is similar in the C-terminal domain. The N-terminal domain of butyrophilin is similar to rat myelin/oligodendrocyte glycoprotein (MOG) and chicken B blood group system (B-G) protein. These domains are components of a new subfamily of the immunoglobulin superfamily (IgSF). Butyrophilin is thus a mosaic protein composed of the MOG/B-G Ig-like domain and the C-terminal domain of 52-kD SS-A/Ro, RFP, and XNF7 (1330-2-like domain). Moreover, in situ hybridization shows that RFP, butyrophilin, and MOG map to the human chromosome 6p2l.3-6p22 region and are thus close to the MHC class I genes. It is therefore possible that the butyrophilin gene is the product of an exon shuffling event which occurred between ancestors of the RFP and MOG genes. To our knowledge, this is the first example of the colocalization of a chimeric gene and its putative progenitors. Finally, regulatory protein T-lymphocyte 1 (Rpt-1) shares similarities with the N-terminal halves of RFP, 52-kD SS-A/Ro, and XNF7, but not with the B30-2-like domain. We show that the ancestral Rpt-l gene evolved by overprinting.
Correspondence to: P. Pontarotti 相似文献
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98.
《Journal of Asia》2023,26(2):102045
Thambus planifrons Muona & Meng sp. nov. and Otho rutriclypeus Muona & Meng sp. nov. are described from China. Both genera are recorded for the first time from China. Except for the European T. friwaldszkyi Bonvouloir, 1871, and the Japanese T. curvicaria Hisamatsu, 1956, all other previously known species belonging to Otho were from the Americas. Eight Otho species have been described from disparate parts of Asia earlier.urn:lsid:zoobank.org:pub:10B667F6-F11E-454B-9653-D66A2D7ABFA1. 相似文献
99.
记述我国新疆和田县球蛛属1新种,命名为和田球蛛,新种Theridon hotanenis Sp.nov。, 相似文献
100.
《Journal of Asia》2023,26(2):102050
Phloeocharis Mannerheim is the largest genus within the problematic rove beetle subfamily Phloeocharinae, with a single extinct and 44 recent species recorded from the Holarctic Region. Until now, the oldest fossil record of Phloeocharis was known from Late Cretaceous (Turonian) amber from New Jersey, USA. Here we describe 2Phloeocharis burmana n. sp. from mid-Cretaceous (Albian–Cenomanian) Kachin amber from northern Myanmar, as the earliest extinct species of this genus. Our finding also sheds light on the biogeography of Phloeocharis, since no recent or extinct species have so far been recorded from the Oriental Region. Furthermore, the discovery of 2P. burmana n. sp. extends the Mesozoic diversity of the phloeocharine rove beetles both taxonomically and morphologically, particularly from Kachin amber. 相似文献