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对民用GPS接收机射频易扰性的评估
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作者 彭获由 《现代电子》 1997年第1期36-42,共7页
引言 GPS的民用市场迅速发展,它为各式应用提供位置和速度信息。GPS由一组卫星组成,它不断地利用直接序列(DS)扩谱信号广播导航信息,其主载波频率(L<sub>1</sub>)为1575.42MHz,次载波频率(L<sub>2</sub>)... 引言 GPS的民用市场迅速发展,它为各式应用提供位置和速度信息。GPS由一组卫星组成,它不断地利用直接序列(DS)扩谱信号广播导航信息,其主载波频率(L<sub>1</sub>)为1575.42MHz,次载波频率(L<sub>2</sub>)为1227.60MHz。 展开更多
关键词 民用GPS接收机 射频 易扰性 接收机
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PCCIP对GPS易扰性表示担忧
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作者 吴晓进 《导航与雷达动态》 1998年第2期45-46,共2页
关键词 卫星导航系统 GPS 易扰性
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Relationship of human leukocyte antigen class II genes with the susceptibility to hepatitis B virus infection and the response to interferon in HBV-infected patients 被引量:28
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作者 Yong-Nian Han Jin-Long Yang Shui-Gen Zheng Qun Tang Wei Zhu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第36期5721-5724,共4页
AIM: To study the relationship of human leukocyte antigen (HLA)-DRB1 and -DQB1 alleles with the genetic susceptibility to HBV infection and the response to interferon (IFN) in HBV-infected patients. METHODS: Low... AIM: To study the relationship of human leukocyte antigen (HLA)-DRB1 and -DQB1 alleles with the genetic susceptibility to HBV infection and the response to interferon (IFN) in HBV-infected patients. METHODS: Low-resolution DNA typing kit was used to determine HLA-DR-1 and -DQB1 genes in 72 patients with chronic hepatitis B (CHB) and HLA-DRB1 in 200 healthy people ready to donate their bone marrow in Shanghai. Among CHB patients, 35 were treated with IFNα-1b for 24 wk. RESULTS: The frequencies of HLA-DRBI*06, DRBI*08 and DRB1*16 alleles in 72 patients were higher than in 200 healthy people (2.08% vs0%, OR = 3.837, P= 0.018; 11.11% vs5.50%, OR = 2.148, P= 0.034; and 6.94% vs 3.00%, OR = 0.625, P = 0.049, respectively); whereas that of DRBI*07 allele was lower (2.78% vs 7.75%, OR = 0.340, P= 0.046). The frequency of HLA-DRBI* 14 allele was higher in 11 responders to IFN compared with 24 non-responders (18.18% vs2.08%, OR = 10.444, P = 0.031), whereas that of DQBI*07 allele was inverse (9.09% vs37.50%, OR = 0.167, P= 0.021). CONCLUSION: The polymorphism of HLA class II may influence the susceptibility to HBV infection and the response to IFN in studied CHB patients. Compared with other HLA-DRB1 alleles, HLA-DRBI*06, DRBI*08, and DRB1*16 may be associated with chronicity of HBV infection, HLA-DRBI*07 with protection against HBV infection, and HLA-DRB1*14 allele may be associated with a high rate of the response of CHB patients to IFN treatment. Compared with other HLA-DQB1 alleles, HLA-DQBI*07 may be associated with low response rate to IFN. 2005 The WJG Press and Elsevier Inc. All rights reserved 展开更多
关键词 Hepatitis B Human leukocyte antigens Geneticsusceptibility INTERFERON
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Assessment of Damage, Infestation Level and Susceptibility of Mango Cultivars to the Fruit Flies Infestation in Shendi Area, Sudan
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作者 Amani M. Khair Faiza M. A. Magid Eltigani E. Ali 《Journal of Life Sciences》 2015年第11期521-525,共5页
Fruit flies are serious pests of Mango in Sudan; they cause substantial damage to Mango production, both qualitatively and quantitatively. This study is an effort to establish information about the pest and, to test t... Fruit flies are serious pests of Mango in Sudan; they cause substantial damage to Mango production, both qualitatively and quantitatively. This study is an effort to establish information about the pest and, to test the susceptibility of some Mango cultivars (Baladi, Kitchener, Shendi, Alphons, Abu Samaka and Bit abusamaka) to the pest infestation. A survey was carded out at Shendi area, River Nile State, during the period of May 2007 to July 2008, using a home made trap resemble lvnfield traps with attractants (Methyl eugenol, Trimedlure, cue lure and Nu lure) to identify the fruit flies species found in the area and to study the seasonal abundance of the pest species and to determine the infestation percentage of different Mango cultivars. Results indicated that the fruit fly Bactrocera invadens is present all year-round in the study area, with population peak July to September. The study showed that Guava ( Psedium guajava ) represents the best alternative host for the pest. Abu samaka and Bit Abusa amaka mango cultivars were the most susceptible, with 100% infestation, followed by Shendi 70%, Kitchener 54%, Alphons and Baladi (30%, 28%, respectively) were the least susceptible. Also results revealed that females of both species Ceratitis cosyra and Bactrocera invadens out numbered males 4-5 times. 展开更多
关键词 Fruit flies INFESTATION mango cultivar.
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Increased susceptibility of algal symbionts to photo-inhibition resulting from the perturbation of coral gastrodermal membrane trafficking
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作者 CHEN Chii-Shiarng YEH Shih-Pin +2 位作者 WANG Li-Hsueh LI Hsing-Hui CHEN Uang Wan-Nan 《Science China(Life Sciences)》 SCIE CAS 2012年第7期599-611,共13页
The stability of cnidarian-dinoflagellate endosymbioses is dependent upon communication between the host gastrodermal cell and the symbionts housed within it. Although the molecular mechanisms remain to be elucidated,... The stability of cnidarian-dinoflagellate endosymbioses is dependent upon communication between the host gastrodermal cell and the symbionts housed within it. Although the molecular mechanisms remain to be elucidated, existing evidence suggests that the establishment of these endosymbioses may involve the sorting of membrane proteins. The present study examined the role of host gastrodermal membranes in regulating symbiont (genus Symbiodinium) photosynthesis in the stony coral Euphyllia glabrescens. In comparison with the photosynthetic behavior of Symbiodinium in culture, the Symbiodinium populations within isolated symbiotic gastrodermal cells (SGCs) exhibited a significant degree of photo-inhibition, as determined by a decrease in the photochemical efficiency of photosystem II (Fv/Fm). This photo-inhibition coincided with increases in plasma membrane perturbation and oxidative activity in the SGCs. Membrane trafficking in SGCs was examined using the metabolism of a fluo- rescent lipid analog, N-[5-(5,7-dimethyl boron dipyrromethene difluoride)-l-pentanoyl]-D-erythro-Sphingosylpbosphoryl- choline (BODIPY-Sphingomyelin or BODIPY-SM). Light irradiation altered both membrane distribution and trafficking of BODIPY-SM, resulting in metabolic changes. Cholesterol depletion of the SGC plasma membranes by methyl-13-cyclodextrin retarded BODIPY-SM degradation and further augmented Symbiodinium photo-inhibition. These results indicate that Symbio- dinium photo-inhibition may be related to perturbation of the host gastrodermal membrane, providing evidence for the pivotal role of host membrane trafficking in the regulation of this environmentally important coral-dinoflagellate endosymbiosis. 展开更多
关键词 CNIDARIA ENDOSYMBIOSIS fluorescent lipids lipid trafficking PAM photosynthesis SYMBIODINIUM
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