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In order to ensure an adequate and safe blood supply, the plateletpheresis donor deferral rate in family replacement donors and volunteer donors were analyzed in this study. The study was undertaken in Chongqing Blood Center, China. Nucleic acid testing (NAT) and ELISA were applied to assess the hepatitis B virus surface antigen (HBsAg), antibodies against hepatitis C virus (anti-HCV), human immunodeficiency virus (HIV) and Treponema palladium(TP)in plateletpheresis donors. From January 2015 to December 2016, a total of 17,342 plateletpheresis donors in Chongqing blood center were enrolled in this study. Among the 3,642 plateletpheresis donors, 21.00% were younger than 25, followed by 26–35 years group (41.19%), 36-45 years group (22.46%), 46-55 years group (13.97%) and 56-60 years group (1.38%). Replacement and voluntary donors contributed 5,305 (30.59%) and 12,037 (69.41%), respectively. Among all the plateletpheresis donors, 194 (1.12%) were deferred because of seropositive serology. Replacement and voluntary deferred donors comprised 109 (2.05%) and 85 (0.68%), respectively (P<0.05). Among the deferred donors, 194 (1.12%) were seropositive for HBsAg (0.44%), followed by anti-HCV (0.28%), TP (0.24%) and HIV (0.15%). Prevalence deferred females contributed 67 (1.60%), while males contributed 127 (0.97%) of the deferred cases, respectively (P<0.05). Deferral rate was highest among 46-55 years group (1.65%) followed by 36-45 years group (1.63%), The other groups were less than 1%. It is necessary to reduce family replacement donors and replace them with regular volunteer donors, and to improve blood donor retention strategies to boost the regular blood donors’ motivating. In addition to increasing and maintaining volunteer supply, it is desirable to keep the deferral rate at a low level, to ensure an adequate and safe blood supply.  相似文献   
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It has been demonstrated that maternal drinking during pregnancy had serious adverse effects on the health of the newborns. Fetal alcohol syndrome (FAS) is the most important developmental abnormality caused by maternal alcohol abuse during pregnancy. Clinically, it is characterized by head and facial ab-normalities, cardiovascular malformation, and perma-nent nervous system damage[1,2]. A lot of experimental models have been developed to study the ethanol’s effects on embryonic development,…  相似文献   
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Cucumber (Cucumis sativus L. 2n = 2x = 14), thatbelongs to Cucurbitaceae family, is one of majorvegetables with a planting area second to that of to-mato in the world[1]. Due to its economical importanceplant breeders and geneticists have paid much atten-tion to the genetic study on this important vegetablecrop, but the research progress in cucumber is muchless than that in tomato. In 1990, Pierce[2] reviewed allthe reported genes of cucumber that had been geneti-cally analyzed since the 1930…  相似文献   
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Bacillus thuringiensis (Bt), a Gram-positive bacte-rium, produces insecticidal crystal proteins during sporulation. Bt has been used as biopesticides to con-trol a number of insect pests from Lepidoptera, Dip-tera and Hymenoptera and also has become so far the leading gene sources of transgenic plants resistant toinsect pests[1,2]. In China, the use of Bt cotton began in 1997 in Hebei, Shandong and Henan provinces, etc. and rapidly increased to more than 2 million ha in 2002, which is effe…  相似文献   
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A novel knottedl-like homeobox (knox) gene, Pttknl (Populus tremulaxtremuloides knottedl), isolated from the cambial region of hybrid aspen, was introduced into Petunia hybrida Vilm. using the leafdisc method mediated by Agrobacterium. A series of novel phenotypes was observed in transgenic petunia plants, including the formation of ectopic spikes on the adaxial surface of corollas and small petals on the abaxial surface of corollas, fusion of floral organs, shortening of corolla midribs, the formation of tumor-like knots along the midrib on the abaxial surface and serrated lobs of corolla margins, and alterations in petal color; except for changes in the leaves and plant architecture, RT-PCR showed that the Pttknl gene was expressed in the leaves of different petunia transgenic plants, whereas no signal was detected in wild-type plants. The possible function of Pttknl in leaf and flower development is discussed.  相似文献   
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In the present study, we report a survey on a Miniature Inverted Transposable Element (MITE) system known as mPing in 102 varieties of Asian cultivated rice (Oryza sativa L.). We found that mPing populations could be generalized Into two families, mPing-1 and mPing-2, according to their sequence structures. Further analysis showed that these two families of mPing had significant bias in their distribution pattern in two subspecies of rice, namely O. sativa ssp. japonica and indica. 0. sativa japonica has a higher proportion of mPing-1 as a general trait, whereas 0. sativa indica has a higher proportion of roPing-2. We also examined the mPing system In a doubled haploid (DH) cross-breeding population of jingxi 17 (japonica) and zhaiyeqing 8 (indica) varieties and observed that the mPing system was not tightly linked to major subspecies-determining genes. Furthermore, we checked the mPing system in 28 accessions of Asian common wild rice O. rufipogon and found the roPing system in 0. rufipogon. The distribution pattern of the roPing system in O. rufipogon indicated a diphyletlc origin of the Asian cultivated rice O. sativa species. We did not find the mPing system in another 20 Oryza species. These results substantiated a previous hypothesis that O. ruflpogon and O. nivara species were the closest relatives of O. sativa and that the two extant subspecies of O. sativa were evolved independently from corresponding ecotypes of O. ruflpogon.  相似文献   
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A cDNA library was constructed end characterized from the pulp of Cera Care navel orange (Citrus sinensis Osbeck) at different stages of ripening. Tittering results revealed that approximately 5.086×10^5 independent clones were included in this library. Electrophoresls gel results of 15 randomly selected clones revealed that the size of the insertion fragments ranged from 400 bp to 2 kb, with an average size of 900 bp. Sequencing results of 150 randomly picked clones showed that the recombination rate was 94%. During subsequent sequence analysis, 41 of 139 clones failed to be identified end the amino sequence of 71 clones shared less than 30% identity with related plants in GenBank. Of 27 clones whose amino sequences shared more than 60% identity with other related plants in GenBenk, 17 clones showed an 80% identity with the corresponding candidate genes of citrus. The clone recognized as the type Ⅲ metallothlonein-llke (MT) gene was observed to occur 13 tlmes, Indlcatlng that the protein may play an important role In frult development and rlpenlng.  相似文献   
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