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991.
Fifteen species in six genera of the family Liliaceae were karyomorphologically studied. They share the complex chromocenter type of the resting nuclei and the interstitial type of the prophase chromosomes in somatic cells except that Clintonia udensis Trautv. et Mey is of the densely diffuse type and gradient type respectively. Their karyotype formulas are listed as follows: Clintonia udensis Trautv. et Mey, 2n= 14=8m+4sm+2st (2SAT), belongs to 2A type; Smilacina henryi (Baker) Wang et Tang, 2n=36=12m+16sm+6st+2t (2SAT), 2C type; Smilacina fusca Wall., 2n = 36= 14m (2SAT)
+ 12sm+ 10st(2SAT), 2B type; Smilacinata tsienensis (Franch.) Wang et Tang, 2n= 36=22m +2sm+ 2st(2SAT), 2C type; Smilacina atropurpurea ( Franch.) Wang et Tang, 2n=36=18m+6sm(2SAT) +12st, 2C type: Polygonatum kingianum Coll, et Hesml., 2n=30= 12m(2SAT) +6sm+ lst+2t, 2C type; Polygonatum cirrhifolium (Wall.) Royal, 2n=30= 10m+4sm+ 12st+4t, 3C type; Polygonatum curvistylum Hua, 2n=78=24m (2SAT)+ 14sm (6SAT)+40st, 3C type; Polygonatum cathcartii Baker, 2n = 32 = 12m + 6sm + 10st+ 2t + 2Bs, 2C type; Lilium henricii Franch., 2n = 24 = 2m(2SAT) + 2sm + 10st+ 10t, 3A type; Lilium bakerianum Coll. et Hesml. var. rubrum Stearn, 2n=24=4m ( 2SAT) +10st+ 10t (2SAT), 3A type; Nomocharis bilouensis Liang, 2n= 24= 2m (2SAT) +2sm+ 12st+ 8t, 3A type; Nomocharis pardanthina Franch., 2n= 24=4m (2SAT)+12st (2SAT)+ 8t, 3A type; Nomocharis sauluensis Balf. f., 2n=24=4m(2SAT) +10st (2SAT) + 10t, 3B type; Notholirion campanulatum Cotton et Stearn 2n = 24 = 2m (2SAT) + 2sm + 14st(2SAT ) + 6t, 3A type. 相似文献
992.
Ming Bian Qian-qian Ma Yun Wu Huan-huan Du Gong Guo-hua 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):2139
Inflammation and disease are closely related. Inflammation can induce various diseases, and diseases can promote inflammatory response, and two possibly induces each other in a bidirectional loop. Inflammation is usually treated using synthetic anti-inflammatory drugs which are associated with several adverse effects hence are not safe for long-term use. Therefore, there is need for anti-inflammatory drugs which are not only effective but also safe. Several researchers have devoted to the research and development of effective anti-inflammatory drugs with little or no side effects. In this review, we studied some small molecules with reported anti-inflammatory activities and hence potential sources of anti-inflammatory agents. The information was retrieved from relevant studies published between January 2019 and May, 2021 for review. This review study was aimed to provide relevant information towards the design and development of effective and safe anti-inflammation agents. 相似文献
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Transduction of modified factor VIII gene improves lentiviral gene therapy efficacy for hemophilia A
Jie Gong Tsai-Hua Chung Jie Zheng Huyong Zheng Lung-Ji Chang 《The Journal of biological chemistry》2021,297(6)
Hemophilia A (HA) is a bleeding disorder caused by deficiency of the coagulation factor VIII (F8). F8 replacement is standard of care, whereas gene therapy (F8 gene) for HA is an attractive investigational approach. However, the large size of the F8 gene and the immunogenicity of the product present challenges in development of the F8 gene therapy. To resolve these problems, we synthesized a shortened F8 gene (F8-BDD) and cloned it into a lentiviral vector (LV). The F8-BDD produced mainly short cleaved inactive products in LV-transduced cells. To improve F8 functionality, we designed two novel F8-BDD genes, one with an insertion of eight specific N-glycosylation sites (F8-N8) and another which restored all N-glycosylation sites (F8-299) in the B domain. Although the overall protein expression was reduced, high coagulation activity (>100-fold) was detected in the supernatants of LV-F8-N8- and LV-F8-299-transduced cells. Protein analysis of F8 and the procoagulation cofactor, von Willebrand Factor, showed enhanced interaction after restoration of B domain glycosylation using F8-299. HA mouse hematopoietic stem cell transplantation studies illustrated that the bleeding phenotype was corrected after LV-F8-N8 or -299 gene transfer into the hematopoietic stem cells. Importantly, the F8-299 modification markedly reduced immunogenicity of the F8 protein in these HA mice. In conclusion, the modified F8-299 gene could be efficiently packaged into LV and, although with reduced expression, produced highly stable and functional F8 protein that corrected the bleeding phenotype without inhibitory immunogenicity. We anticipate that these results will be beneficial in the development of gene therapies against HA. 相似文献
996.
Xiao Ge Xiang Zhao Akihisa Nakagawa Xinqi Gong Riley Robert Skeen-Gaar Yong Shi Haipeng Gong Xinquan Wang Ding Xue 《Cell research》2014,24(2):218-232
During C. elegans apoptosis, the dicer ribonuclease (DCR-1) is cleaved by the cell death protease CED-3 to generate a truncated DCR-1 (tDCR-1) with one and a half ribonuclease III (RNase III) domains, converting it into a deoxyribonuclease (DNase) that initiates apoptotic chromosome fragmentation. We performed biochemical and functional analyses to understand this unexpected RNase to DNase conversion. In full-length DCR-1, tDCR-1 DNase activity is suppressed by its N-terminal DCR-1 sequence. However, not all the sequence elements in the N-terminal DCR-1 are required for this suppression. Our deletion analysis reveals that a 20-residue α-helix sequence in DCR-1 appears to define a critical break point for the sequence required for suppressing tDCR-1 DNase activity through a structure-dependent mechanism. Removal of the N-terminal DCR-1 sequence from tDCR-1 activates a DNA-binding activity that also requires the one half RNase IIIa domain, and enables tDCR-1 to process DNA. Consistently, structural modeling of DCR-1 and tDCR-1 suggests that cleavage of DCR-1 by CED-3 may cause a conformational change that allows tDCR-1 to bind and process DNA, and may remove steric hindrance that blocks DNA access to tDCR-1. Moreover, a new DNase can be engineered using different RNase III domains, including the one from bacterial RNase III. Our results indicate that very distantly related RNase III enzymes have the potential to cleave DNA when processed proteolytically or paired with an appropriate partner that facilitates binding to DNA. We suggest the possibility that this phenomenon may be extrapolated to other ribonucleases. 相似文献
997.
Huai Chen Qiuan Zhu Changhui Peng Ning Wu Yanfen Wang Xiuqing Fang Yongheng Gao Dan Zhu Gang Yang Jianqing Tian Xiaoming Kang Shilong Piao Hua Ouyang Wenhua Xiang Zhibin Luo Hong Jiang Xingzhang Song Yao Zhang Guirui Yu Xinquan Zhao Peng Gong Tandong Yao Jianghua Wu 《Global Change Biology》2013,19(10):2940-2955
With a pace of about twice the observed rate of global warming, the temperature on the Qinghai‐Tibetan Plateau (Earth's ‘third pole’) has increased by 0.2 °C per decade over the past 50 years, which results in significant permafrost thawing and glacier retreat. Our review suggested that warming enhanced net primary production and soil respiration, decreased methane (CH4) emissions from wetlands and increased CH4 consumption of meadows, but might increase CH4 emissions from lakes. Warming‐induced permafrost thawing and glaciers melting would also result in substantial emission of old carbon dioxide (CO2) and CH4. Nitrous oxide (N2O) emission was not stimulated by warming itself, but might be slightly enhanced by wetting. However, there are many uncertainties in such biogeochemical cycles under climate change. Human activities (e.g. grazing, land cover changes) further modified the biogeochemical cycles and amplified such uncertainties on the plateau. If the projected warming and wetting continues, the future biogeochemical cycles will be more complicated. So facing research in this field is an ongoing challenge of integrating field observations with process‐based ecosystem models to predict the impacts of future climate change and human activities at various temporal and spatial scales. To reduce the uncertainties and to improve the precision of the predictions of the impacts of climate change and human activities on biogeochemical cycles, efforts should focus on conducting more field observation studies, integrating data within improved models, and developing new knowledge about coupling among carbon, nitrogen, and phosphorus biogeochemical cycles as well as about the role of microbes in these cycles. 相似文献
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AC—PCR法检测连云港海域贝类HAV 总被引:2,自引:0,他引:2
为了解连云港海域贝类甲型肝炎病毒(HAV)污染状况,证实其在本地区甲肝传播中的媒介地位,我们应用抗体捕捉聚合酶链反应(AC/PCR)检测市售贝类的HAV,结果报告如下:材料和方法1贝类样品于1996年春、秋二季采集新浦区、连云区和赣榆县等地水产品市场... 相似文献