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1.
Duoru Lin Jingjing Chen Zhuoling Lin Xiaoyan Li Xiaohang Wu Erping Long Lixia Luo Bo Zhang Hui Chen Wan Chen Li Zhang Haotian Lin Weirong Chen Yizhi Liu 《PloS one》2015,10(11)
A review of 6 years of hospitalization charts from Zhongshan Ophthalmic Center (ZOC) revealed that congenital cataracts (CC) accounted for 2.39% of all cataract in-patient cases and that the age at surgery was decreasing before the establishment of the Childhood Cataract Program of the Chinese Ministry of Health (CCPMOH) in December 2010. We aimed to investigate data from the 4 years (January 2011 to December 2014) following the establishment of the CCPMOH, compared, and combined with data from the previous study period (January 2005 to December 2010) to generate a 10-year overview of the hospital-based prevalence and treatment of CC. In the 4-year period after CCPMOH establishment, the prevalence of CC was 2.01% in all hospitalizations, and was 2.78% in all cataract in-patients. Most of the eligible CC in-patients (71%) lived in south China. The ratio of boys to girls was 1.42:1. Nearly 2/3 of the patients underwent cataract extraction with primary intraocular lens (IOL) implantation at a mean age of 78.40±51.45 months, and cataract extraction surgeries without IOL implantation were performed in the remaining 1/3 of patients at a mean age of 10.03±15.92 months. After CCPMOH establishment, an increased incidence of CC was revealed, and the CC in-patients were younger than the patients in the previous period. The 10-year overview (2421 CC in-patients from 206630 hospitalizations) revealed upward trends in both the number and the prevalence of CC and a further reduction in age at surgery. In conclusion, the data from 4-year period after CCPMOH establishment and the 10-year overview showed upward trends in the hospital-based prevalence of CC cases and a further reduction in age at surgery, likely reflecting the effects of the CCPMOH establishment and providing useful information for further CC studies and a valuable foundation for the prevention and treatment of this cause of childhood blindness. 相似文献
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Food availability is important to the dynamics of animal social organizations or populations. However, the role of winter
food availability in animal population dynamics is still controversial. We carried out an experimental study to test Lack’s
hypothesis that reduced food in winter limits survival and spring numbers of breeding individuals of social groups, using
the Mongolian gerbil (Meriones unguiculatus) as model species. We established 24 gerbil social groups in 24, 10 × 10 m, pens in September 2008. We provided wheat seeds
as supplemental food in 12 enclosures from September 2008 to March 2009; the other 12 enclosures, not provided with supplemental
food, served as controls. We live-trapped gerbils at a 2-week interval from September to April. Supplemental food during winter
increased biweekly survival by 10% relative to that in control groups. Only four control social groups survived to the end
of our study whereas all 12 food-supplemented social groups survived through our study period. Supplemental food also increased
cumulative numbers of recruits and group sizes of gerbils. We conclude that winter food availability limits winter survival
and spring social groups or population sizes of Mongolian gerbils. 相似文献
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The psychrophile Clostridium sp. strain 69 contains a thermolabile triose phosphate isomerase which is inactivated rapidly in vitro and in vivo at 32 C. 相似文献
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Yuxi Tian Liangfang Shen Fujun Li Junwen Yang Xiaoping Wan Miao Ouyang 《Journal of cellular physiology》2020,235(1):442-453
Colorectal cancer (CRC) is commonly known as one of the most prominent reasons for cancer-related death in China. Ras homolog enriched in brain (RHEB) and the mammalian target activity of rapamycin (mTOR) signaling pathway were found correlated with CRC, but their specific interaction in CRC was still to be investigated. Therefore, we explored whether RHEB gene silencing affected the cell proliferation, differentiation, and apoptosis by directly targeting the mTOR signaling pathway in cells previously harvested from CRC patients. A microarray analysis was subsequently conducted to investigate the relationship between RHEB and mTOR. Eighty-three adjacent normal tissues and CRC tissues were selected. Immunohistochemistry was carried out to detect the positive expression rates of RHEB and Ki-67 in the CRC tissues. Cells were then transfected with different siRNAs to investigate the potential effects RHEB would have on CRC progression. The expressions of RHEB, 4EBP1, ribosomal protein S6 kinase (p70S6K), proliferating cell nuclear antigen (PCNA), B cell lymphoma 2 (bcl-2), and bcl-2-associated X protein (bax) were determined and then the cell cycle, cell proliferation, and apoptotic rate were also measured. We identified RHEB and mTOR as upregulated genes in CRC. Cells treated with RHEB silencing showed a decreased extent of mTOR, p70S6K, 4EBP1 phosphorylation and expression of RHEB, Ki-67, mTOR, p70S6K, 4EBP1, bcl-2, and PCNA as well as decreased activity of cell proliferation and differentiation; although, the expression of bax was evidently higher. Collectively, our data propose the idea that RHEB gene silencing might repress cell proliferation and differentiation while accelerating apoptosis via inactivating the mTOR signaling pathway. 相似文献
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为研究鸭C4结合蛋白(C4b-binding protein,C4BP)与鸭疫里默氏菌(Riemerella anatipestifer,RA)的相互作用,对鸭C4BPα进行克隆、原核表达,免疫小鼠制备多克隆抗体,并利用间接免疫荧光试验及斑点杂交试验验证C4BP与RA的相互作用。结果显示,鸭C4BPα核苷酸序列全长为1230bp,与鸡C4BPα的相似性最高(82.1%);系统进化树分析发现,鸭C4BPα与鸡C4BPα处于同一系统进化树分支上,两者遗传进化关系最近;C4BPα在大肠杆菌Escherichia coli BL21 (DE3)中能高效表达,重组蛋白以胞内可溶性形式存在;多克隆抗体效价超过1∶10000,并且可以与重组蛋白发生特异性反应;间接免疫荧光试验和斑点杂交试验结果显示RA与鸭C4BP可以发生相互作用。研究结果为进一步揭示RA的致病机制奠定了基础。 相似文献
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Does hydraulic lift exist in shallow-rooted species? A quantitative examination with a half-shrub Gutierrezia sarothrae 总被引:1,自引:0,他引:1
Hydraulic lift occurs in some deep-rooted shrub and herbaceous species. In this process, water taken up by deep roots from
the moist subsoil is delivered to the drier topsoil where it is later reabsorbed by shallow roots. However, little is known
about the existence of hydraulic lift in shallow-rooted xeric species. The objectives of this study were 1) to ascertain whether
hydraulic lift exists in Gutierrezia sarothrae (broom snakeweed), a widespread North American desert species with a shallow root system, grown in pot and field conditions
and 2) if it does, how much water can be transferred from the subsoil to the 30 cm topsoil during the night. Snakeweed seedlings
were transplanted in buried pots allowing the deeper roots to grow into the subsoil 30 cm below the surface. Soil water content
inside and outside of the pot was measured seasonally and diurnally with time domain reflectometry technique (TDR). An increase
in water content was detected in the pot after the plant was covered for 3 h by an opaque plastic bag during the day, suggesting
hydraulic lift from deeper depths and exudation of water into the drier topsoil. Root exudation was also observed on native
range sites dominated by snakeweed. Water efflux in the pot was 271 g per plant per night. which was equivalent to 15.3% of
the extrapolated, porometer-derived whole-plant daily transpiration. Hydraulic lift observed in Gutierrezia improved water uptake during the day when evaporative demand is high and less water is available in the topsoil. We concluded
that hydraulic lift might help snakeweed to alleviate the effect of water stress. 相似文献