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排序方式: 共有633条查询结果,搜索用时 233 毫秒
71.
海菜花(水鳖科)-新变种-嵩明海菜花 总被引:1,自引:0,他引:1
报道了海菜花-新变种-嵩明海菜花(Ottelia acuminata var.songmingensis Z.T.Jiang,H.Li et Z.L.Dao)。该变种与原变种的区别在于叶片带状厚纸质,不透明,叶尖钝圆或具短尖。 相似文献
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认识和改良中国小麦蛋白质量的遗传基础:策略与现有的研究@王道文$中国科学院遗传研究所植物细胞与染色体工程国家重点实验室!北京100101@曲乐庆$中国科学院遗传研究所植物细胞与染色体工程国家重点实验室!北京100101@贾旭$中国科学院遗传研究所植物细胞与染色体工程国家重点实验室!北京100101@张相岐$中国科学院遗传研究所植物细胞与染色体工程国家重点实验室!北京100101@万永芳$中国科学院遗传研究所植物细胞与染色体工程国家重点实验室!北京100101@李振声$中国科学院遗传研究所植物细胞与染色体工程国家重点实验室!北京100101小麦;;蛋白… 相似文献
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Mechanisms that coordinate growth during development are essential for producing animals with proper organ proportion. Here we describe a pathway through which tissues communicate to coordinate growth. During Drosophila melanogaster larval development, damage to imaginal discs activates a regeneration checkpoint through expression of Dilp8. This both produces a delay in developmental timing and slows the growth of undamaged tissues, coordinating regeneration of the damaged tissue with developmental progression and overall growth. Here we demonstrate that Dilp8-dependent growth coordination between regenerating and undamaged tissues, but not developmental delay, requires the activity of nitric oxide synthase (NOS) in the prothoracic gland. NOS limits the growth of undamaged tissues by reducing ecdysone biosynthesis, a requirement for imaginal disc growth during both the regenerative checkpoint and normal development. Therefore, NOS activity in the prothoracic gland coordinates tissue growth through regulation of endocrine signals. 相似文献
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Shuai Yuan Huaping Li Chen Chen Feng Wang Dao Wen Wang 《Journal of cellular and molecular medicine》2021,25(7):3484-3497
Patients with hyperglycemia tend to be susceptible to Coronavirus disease 2019 (COVID-19). However, the association of HbA1c level with outcome of COVID-19 patients was unclear. We performed a retrospective study of 2880 cases of COVID-19 admitted in Tongji Hospital, Wuhan, China, among which 922 had detected the HbA1c levels. We found that COVID-19 patients with either lower levels of HbAlc (3%-4.9%) or higher levels of HbAlc (≥6%) were associated with elevated all-cause mortality. Meanwhile, we observed that HbAlc levels were highly correlated with haemoglobin (Hb) and total cholesterol (TC) (P < .0001), moderately correlated with albumin (ALB) and high-sensitive C reaction protein (hs-CRP) (0.0001 < P<.001), and relatively low correlated with low-density lipoprotein cholesterol (LDL-C) (.001 < P<.01). These associated cofactors might together contribute to the clinical outcome of COVID-19 patients. Furthermore, the mortality was higher in COVID-19 patients with newly diagnosed diabetes mellitus (DM) compared with COVID-19 patients with history of DM. Moreover, in patients with history of DM, the mortality was decreased in patients treated with anti-hyperglycaemic drugs. In summary, our data showed that the in-hospital mortality was increased in COVID-19 patients with lower or higher levels of HbAlc. Meanwhile, initiation of appropriate anti-hyperglycaemic treatment might improve the clinical outcome in COVID-19 patients. 相似文献
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Numerous copies of endogenous retroviruses are present in the genome of mammals including man. Although most of them are defective, some, e.g., the human endogenous retroviruses HERV-K, were found to be expressed under certain physiological conditions. For instance, HERV-K is expressed in germ cell tumours and melanomas as well as in the placenta. Most exogenous retroviruses including the human immunodeficiency virus HIV-1 induce severe immunodeficiencies and there is increasing evidence that the transmembrane envelope (TM) proteins of these retroviruses may be involved. We show here that HERV-K particles released from a human teratocarcinoma cell line, a recombinant TM protein and a peptide corresponding to a highly conserved so-called immunosuppressive domain in the TM protein of HERV-K inhibit the proliferation of human immune cells, induce modulation of the expression of numerous cytokines, and modulate the expression of cellular genes as detected by a microarray analysis. The changes in cytokine release and gene expression induced by the TM protein of HERV-K are similar to those found previously induced by the TM protein of HIV-1. These data suggest that the mechanism of immunosuppression may be similar for different retroviruses and that the expression of the TM protein in tumours and in the placenta may suppress immune responses and thus prevent rejection of the tumour and the embryo. 相似文献
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Viet Hung Dao Isabelle Ourliac-Garnier Marc-Antoine Bazin Catherine Jacquot Blandine Baratte Sandrine Ruchaud Stéphane Bach Olivier Grovel Patrice Le Pape Pascal Marchand 《Bioorganic & medicinal chemistry letters》2018,28(13):2250-2255
In a context of growing resistance to classical antifungal therapy, the design of new drugs targeting alternative pathways is highly expected. Benzofuro[3,2-d]pyrimidine derivatives, derived from (?)-cercosporamide, were synthesized and evaluated as potential Candida albicans PKC inhibitors in the aim of restoring susceptibility to azole treatment. Co-administration assay of benzofuropyrimidinedione 23 and fluconazole highlighted a synergistic effect on inhibition of cell growth of a Candida albicans resistant strain. 相似文献