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Qian‐Quan LI Min‐Hui LI Qing‐Jun YUAN Zhan‐Hu CUI Lu‐Qi HUANG Pei‐Gen XIAO 《植物分类学报:英文版》2013,51(2):184-195
With 84 native species, China is a center of distribution of the genus Salvia (Lamiaceae). These species are mainly distributed in Yunnan and Sichuan provinces (southwestern China), notably the Hengduan Mountain region. Traditionally, the Chinese Salvia has been classified into four subgenera, Salvia, Sclarea, Jungia, and Allagospadonopsis. We tested this classification using molecular phylogenetic analysis of 43 species of Salvia from China, six from Japan, and four introduced species. The nuclear ribosomal internal transcribed spacer region and three chloroplast regions (rbcL, matK, and trnH-psbA) were analyzed by maximum parsimony, maximum likelihood, and Bayesian methods. Our results showed that the Chinese (except Salvia deserta) and Japanese Salvia species formed a well-supported clade; S. deserta from Xinjiang grouped with Salvia officinalis of Europe. In addition, all introduced Salvia species in China were relatively distantly related to the native Chinese Salvia. Our results differed from the subgeneric and section classifications in Flora Reipublicae Popularis Sinicae. We suggested that sections Eusphace and Pleiphace should be united in a new subgenus and that sect. Notiosphace should be removed from subg. Sclarea and form a new subgenus. Our data could not distinguish a boundary between subg. Allagospadonopsis and sect. Drymosphace (subg. Sclarea); the latter should be reduced into the former. Further clarification of the phylogenetic relationships within Salvia and between Salvia and related genera will require broader taxonomic sampling and more molecular markers. 相似文献
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Jie Dong Jun Lei Nada A. Elsayed Ji Yeon Lee Na Shin Quan Na Anna Chudnovets Bei Jia Xiaohong Wang Irina Burd 《Developmental neurobiology》2020,80(5-6):149-159
Fetuses exposed to an inflammatory environment are predisposed to long‐term adverse neurological outcomes. However, the mechanism by which intrauterine inflammation (IUI) is responsible for abnormal fetal brain development is not fully understood. The mechanistic target of rapamycin (mTOR) signaling pathway is closely associated with fetal brain development. We hypothesized that mTOR signaling might be involved in fetal brain injury and malformation when fetuses are exposed to the IUI environment. A well‐established IUI model was utilized by intrauterine injection of lipopolysaccharide (LPS) to explore the effect of IUI on mTOR signaling in mouse fetal brains. We found that microglia activation in LPS fetal brains was increased, as demonstrated by elevated Iba‐1 protein level and immunofluorescence density. LPS fetal brains also showed reduced neuronal cell counts, decreased cell proliferation demonstrated by low Ki67‐positive density, and elevated neuron apoptosis evidenced by high expression of cleaved Caspase 3. Furthermore, we found that mTOR signaling in LPS fetal brains was elevated at 2 hr after LPS treatment, declined at 6 hr and showed overall inhibition at 24 hr. In summary, our study revealed that LPS‐induced IUI leads to increased activation of microglia cells, neuronal damage, and dynamic alterations in mTOR signaling in the mouse fetal brain. Our findings indicate that abnormal changes in mTOR signaling may underlie the development of future neurological complications in offspring exposed to prenatal IUI. 相似文献
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Forecasting technological progress is of great interest to engineers, policy makers, and private investors. Several models have been proposed for predicting technological improvement, but how well do these models perform? An early hypothesis made by Theodore Wright in 1936 is that cost decreases as a power law of cumulative production. An alternative hypothesis is Moore''s law, which can be generalized to say that technologies improve exponentially with time. Other alternatives were proposed by Goddard, Sinclair et al., and Nordhaus. These hypotheses have not previously been rigorously tested. Using a new database on the cost and production of 62 different technologies, which is the most expansive of its kind, we test the ability of six different postulated laws to predict future costs. Our approach involves hindcasting and developing a statistical model to rank the performance of the postulated laws. Wright''s law produces the best forecasts, but Moore''s law is not far behind. We discover a previously unobserved regularity that production tends to increase exponentially. A combination of an exponential decrease in cost and an exponential increase in production would make Moore''s law and Wright''s law indistinguishable, as originally pointed out by Sahal. We show for the first time that these regularities are observed in data to such a degree that the performance of these two laws is nearly the same. Our results show that technological progress is forecastable, with the square root of the logarithmic error growing linearly with the forecasting horizon at a typical rate of 2.5% per year. These results have implications for theories of technological change, and assessments of candidate technologies and policies for climate change mitigation. 相似文献
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Gaochen Lu Weihong Wang Pan Li Quan Wen Bota Cui Faming Zhang 《Microbial biotechnology》2022,15(9):2439-2449
The safety, quantitative method and delivery of faecal microbiota transplantation (FMT) vary a lot from different countries in practice. Recently, the improved methodology of FMT based on the automatic filtration, washing process and the related delivery was named as washed microbiota transplantation (WMT). First, this study aimed to describe the methodology development of FMT from manual to washing preparation from 2012 to 2021 in China Microbiota Transplantation System (CMTS), a centralized stool bank for providing a national non-profit service. The secondary aim is to describe donor screenings, the correlation between faecal weight and treatment doses, incidence of adverse events and delivery decision. The retrospective analysis on the prospectively recorded data was performed. Results showed that the success rate of donor screening was 3.1% (32/1036). The incidence rate of fever decreased significantly from 19.4% (6/31) in manual FMT to 2.7% (24/902) in WMT in patients with ulcerative colitis (UC), which made UC a considerable disease model to reflect the quality control of faecal microbiota preparation. We defined one treatment unit as 10 cm3 microbiota precipitation (1.0 × 1013 bacteria) based on enriched microbiota instead of rough faecal weight. For delivering microbiota, colonic transendoscopic enteral tube is a promising way especially for multiple WMTs or frequent colonic administration of drugs combined with WMT. This study should help improve the better practice of FMT for helping more patients in the future. 相似文献
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成功构建pET-24a-tscd质粒,实现Thermococcus sp.Strain B1001来源的环糊精酶(TsCDase)在Es-cherichia coli BL21(DE3)中表达.通过热处理和镍柱分离对重组TsCDase进行纯化.酶学性质研究表明,重组TsCDase的比活为1 208.04 U/mg,最适温度为90℃、最适pH值为5.5.重组酶TsCDase在85℃、90℃、95℃条件下的半衰期分别为180、120、30min.酶转化研究表明,以80 g/L β-环糊精为底物,当酶转化温度为90℃、反应pH值为5.5~6.0,加酶量为25 U/g,反应时间为4 h时,麦芽七糖产率为81.19%和85.95%,七糖占产物麦芽寡糖的比例为95.24%和92.92%.本研究结果为工业化制备麦芽七糖奠定良好基础. 相似文献