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81.
Sil-Gu Mun Jung-Hyung Moon Ki-Man Choi Jin-Serk Baik Chang-Hee Lee 《Photonics Technology Letters, IEEE》2007,19(21):1729-1731
We propose and demonstrate a wavelength-division-multiplexed passive optical network by employing double-contact Fabry-Perot laser diodes (F-P LDs) without a seed light injection. To avoid the high mode partition noise at low frequency, we use a binary phase-shift keying as a modulation format at a low relative intensity noise window. An error-free transmission is achieved by compensating a lasing envelope shift due to temperature variation with the double-contact F-P LD. 相似文献
82.
明眸晧齿,笑容爽朗,脸部轮廓分明。看到袁泉,马上会有清冽甘甜的感觉,一如她的名字,仿佛夏日里活力天然的一泓清泉。从《春天的狂想》到娃哈哈广告中的美丽少女,袁泉给人的印象一直是青春、健康而甜美的,举手投足,一颦一笑,洋溢着独有的耀眼活力。不久前,这位活力闰女更是担任了“中国女性健康白皮书系列活动”的形象大使。作为宣传女性健康的代言人,袁泉呼吁,要让更多的女性认识到:健康的身体才是美丽人生的根基。[编者按] 相似文献
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CG Dais J Prazma SS Ball C Zdanski V Carrasco HC Pillsbury 《Canadian Metallurgical Quarterly》1996,99(1-2):1-6
OBJECTIVE: Trials that do not allow rejection of the null hypothesis of no treatment effect may have had an inappropriate design. Trials are virtually never assessed for correlation between responses to different treatment modalities. METHODS: Using a hypothetical example and several published studies we examine the influence of correlation levels between treatment modalities on the sensitivity of testing. RESULTS: The level of correlation between responses to different treatment modalities is a major determinant of the sensitivity both of crossover and parallel group clinical trials. CONCLUSIONS: It is very relevant to assess a priori correlation levels between responses to the different treatment modalities of a trial. If a negative correlation is anticipated, a crossover design is likely to lack sensitivity. If a positive correlation is anticipated a parallel-group design seems less appropriate, because it would lack the extra sensitivity of accounting for the positive correlation. Both designs would seem suitable for approximately zero correlations (e.g. comparison vs baseline or vs placebo under the assumption that the number of placebo responders is negligible. 相似文献
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Children with severe combined immunodeficiency (SCID) have profoundly diminished humoral and cellular immunity resulting in death during infancy unless immune reconstitution occurs by bone marrow transplantation (BMT). Thrombocytopenia post-bone marrow transplantation can be seen in relation to infection, graft-versus-host disease (GVHD) and rarely, as an autoimmune phenomenon due to immune dysregulation. We report two cases of severe AITP following BMT for SCID. Both cases developed large intracerebral hemorrhages from which one died. Autoimmune thrombocytopenia in this setting can be life-threatening and we recommend early and active intervention. 相似文献
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SS Tseng PL Weaver Y Liu M Hitomi AM Tartakoff TH Chang 《Canadian Metallurgical Quarterly》1998,17(9):2651-2662
The DBP5 gene encodes a putative RNA helicase of unknown function in the yeast Saccharomyces cerevisiae. It is shown here that Dbp5p is an ATP-dependent RNA helicase required for polyadenylated [poly(A)+] RNA export. Surprisingly, Dbp5p is present predominantly, if not exclusively, in the cytoplasm, and is highly enriched around the nuclear envelope. This observation raises the possibility that Dbp5p may play a role in unloading or remodeling messenger RNA particles (mRNPs) upon arrival in the cytoplasm and in coupling mRNP export and translation. The functions of Dbp5p are likely to be conserved, since its potential homologues can be found in a variety of eukaryotic cells. 相似文献