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1.
QIAN‐WAN MENG YI‐BO LUO 《Botanical journal of the Linnean Society. Linnean Society of London》2008,158(4):689-695
A new species, Galearis huanglongensis Q.W.Meng & Y.B.Luo, is described and illustrated. It is similar to Galearis cyclochila (Franch. & Sav.) Soó and Galearis diantha (Schltr.) P.F.Hunt, but differs in having a short spur, two elliptical lateral stigma lobes and distinctly separated bursicles. This new species is known only from the type locality, the Huanglong Valley, Songpan County, western Sichuan, China, growing amongst mosses under alpine shrubs at an elevation of about 3000 m. Based on two years of observations of its population size, the species was categorized as critically endangered CR (B1a, B2a) according to the World Conservation Union (IUCN) Red List Categories and Criteria, Version 3.1. The micromorphology of pollinia and seeds was observed by scanning electron microscopy and compared with that of G. cyclochila and G. diantha. The results supported G. huanglongensis Q.W.Meng & Y.B.Luo as a new species. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 689–695. 相似文献
2.
D P Kozlov 《Parazitologiia》1972,6(4):360-363
3.
基于MODIS NDVI的长江中游区域植被动态及与气候因子的关系 总被引:1,自引:0,他引:1
基于1999-2015年的MODIS NDVI时间序列遥感数据,应用趋势分析、变异系数、重标极差分析和偏相关分析等方法,分析了长江中游的植被时空变化特征及其与气象因子的关系。结果表明,长江中游地区NDVI均值总体上呈上升趋势(从0.72增加到0.80)。从空间分布来看,NDVI低值区域(0.1-0.5)占1.40%,高值区域(>0.7)占87.15%;NDVI空间格局呈"西高东低、北高南低"的分布特征,低值区域表现为以三省省会城市为中心向外辐射。Hurst指数显示,研究区大部分区域(60.54%)的NDVI变化趋势具有不确定性,持续性改善区域(34.78%)主要分布在西部山地区,持续性退化区域(3.26%)主要分布在人类活动频繁的较发达城市区域。在年际尺度上,研究区NDVI与各气象因子关系均不显著;月际尺度上,NDVI与降水、相对湿度和日照时数显著相关,降水和日照时数有明显的时滞性。区域内NDVI动态趋势以不确定性发展为主,城市群周边NDVI呈现持续退化的区域应该引起关注。 相似文献
4.
The character of metastasis of 9 strains of transplantable mouse tumours in conventional subcutaneous inoculation was studied. There were differences in the frequency, intensity, and types of metastasis of different tumours. Periods of onset of metastases of Lewis lung carcinoma and RL-67, and also of sarcoma-37 were established. Sarcoma, Lewis and RL-67 lung carcinomas, adenocarcinoma of the colon AKATOL, Cloudman's melanoma and B-16 metastasized most intensively. Sarcoma-37 metastasizing into the regional and remote lymph nodes, Lewis lung carcinoma and melanomas metastasizing into the lungs, RL-67 lung carcinoma metastasizing into the lungs, kidneys, adrenal glands, ovaries, the heart, and also adenocarcinoma of the colon AKATOL metastasizing into the lymph nodes and the liver can be used as models for the research in the field of drug action upon metastases and the metastasis process. 相似文献
5.
The primary structure of the operons coding for Shigella dysenteriae toxin and temperature phage H30 shiga-like toxin 总被引:9,自引:0,他引:9
Nucleotide(nt) sequences were determined for the toxin (SHT) operon present in the chromosome of Shigella dysenteriae 1 and for the shiga-like toxin (SLT) operon found in the lambdoid phage H30 genome. The coding sequences of the sht and slt genes differ in 4 nt with 1 nt change responsible for an amino acid replacement. The deduced amino acid sequence in the A chain of the toxins is highly homologous to that of the A chain of ricin, a plant toxin. SHT-coding mRNAs were detected by mapping the 5' termini and using blot-hybridisation; one of them was more abundant and coded only for the B subunit of SHT while the other (bi-cistronic mRNA) encoded both subunits. An IS element related to the IS3 element of Escherichia coli was found in the chromosome of S. dysenteriae near the sht operon. 相似文献
6.
Phase-coherent characteristics of neocortex background electrical activity were studied in a wide frequency range (1-100 Hz) during interstimulus periods in the process of elaboration of motor alimentary conditioned reflexes in dogs. It was shown that the process of learning led to a considerable increase of the part of high (greater than 0.75) and significant (0.5-0.75) coherences, and also of small (0 +/- 15 degrees) and accounted (+/- 16 - +/- 30 degrees) phasic shifts as compared with the state of calm wakefulness. This increase lay mainly in the high-frequency range (40-100 Hz). The analysis of the interregional relations showed that they differed not only by values of phase-coherent characteristics, but also by distributions of the latter. The obtained data testify that the state of activation is manifested both in the rise of frequency of potentials oscillations and in the increase of their synchronization. 相似文献
7.
N F Riabchenko L M Rumer V A Livshits Iu I Kozlov 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》1988,(8):23-28
Streptococcal broad host range plasmid pAM beta 1 was transferred by a conjugation-like process from Streptococcus faecalis to 13 strains of different Bacilli species. In intraspecies matings the frequencies of transfer of pAM beta 1 varied from 2.10(-5) to 1.10(-8). As it was shown by comparative analysis the frequency of transfer and stability of the maintainance of plasmid pAM beta 1 in Bacilli were not connected. Molecular weight and restriction pattern of pAM beta 1 DNA isolated from Bacilli were the same as those of pAM beta 1 DNA from Streptococcal donor strain. 相似文献
8.
Mechanical properties of the red cell membrane skeleton: analysis of axisymmetric deformations 总被引:1,自引:0,他引:1
The mechanical properties of erythrocyte membrane composed of a membrane bilayer and membrane skeleton are considered. Two membrane models are described: the model of free boundaries (MFB) and the model of immobilized boundaries (MIB). In MFB, the skeleton is assumed to be attached to the bilayer at a finite number of points, whereas MIB allows the interaction of each spectrin filament with the bilayer along its whole length. For MFB an estimate was made of the mechanical strain generated in the membrane by sucking erythrocytes into a micropipette. The existence of the deformation threshold is demonstrated, below which no mechanical strain, except that of bending, appears in the membrane. Thus only deformations exceeding this threshold result in strain. The relationship between the applied tension and the height of erythrocyte "tongue" sucked into a micropipette was determined. The MIB characteristics correspond to the model of Evans: strains in the membrane are generated at any deformation, however small, i.e. the threshold is equal to zero. A basic feature of this model is quite a different distribution of the skeleton deformations in the membrane. A comparison of the theoretical models and experimental data demonstrated the possibility of either MFB or MIB occurring, depending on the characteristic measurement time. 相似文献
9.
As it is previously shown (Tsyrlova et al., 1986), the level of humoral immune response is not only determined by the reaction of peripheral lymphoid system on antigenic effect, but also is bound up with the observed stem blood cell (SBC) proliferation in bone marrow (Frindel et al., 1976, Kozlov et al., 1982). Dynamics of label accumulation in bone marrow was examined when injecting antigen--sheep red blood cells labeled by radioisotope 51Cr, 125I. The peak of label accumulation in bone marrow, accompanied by the increase in proliferative SBC, was observed on the 3rd day after antigen injection. Furthermore in the course of immunization 51Cr labeled macrophage assortment was changed in time in such a way that a greater number of macrophages was accumulated in bone marrow on the 3rd and 4th days in the immunized animals in comparison with the intact ones. The macrophages in bone marrow are likely to take part in antigen uptake and to mediate its effect on SBC proliferation. 相似文献
10.