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BackgroundDengue fever has been a significant public health challenge in China. This will be particularly important in the context of global warming, frequent international travels, and urbanization with increasing city size and population movement. In order to design relevant prevention and control strategies and allocate health resources reasonably, this study evaluated the economic burden of dengue fever in China in 2019.MethodsThe economic burden of dengue fever patients was calculated from both family and the organisation perspectives. A survey was conducted among 1,027 dengue fever patients in Zhejiang, Chongqing, and Yunnan Provinces. Treatment expenses, lost working days, and insurance reimbursement expenses information were collected to estimate the total economic burden of dengue fever patients in 2019. The expenditures related to dengue fever prevention and control from government, Center for Disease Control and Prevention (CDC), communities and subdistrict offices of 30 counties (or districts) in Zhejiang Province and Chongqing City were also collected.ResultsThe direct, indirect and total economic burden for dengue fever patients in 2019 in the three Provinces were about 36,927,380.00 Chinese Yuan (CNY), 10,579,572.00 CNY and 46,805,064.00 CNY, respectively. The costs for prevention and control of dengue fever for the counties (or districts) without cases, counties (or districts) with imported cases, and counties (or districts) with local cases are 205,800.00 CNY, 731,180.00 CNY and 6,934,378.00 CNY, respectively. The total investment of dengue fever prevention and control in the 30 counties in China in 2019 was approximately 3,166,660,240.00 CNY.ConclusionThe economic burden of dengue fever patients is relatively high, and medical insurance coverage should be increased to lighten patients’ direct medical economic burden. At the same time, the results suggests that China should increase funding for primary health service institutions to prevent dengue fever transmission.  相似文献   
84.
A series of 1,2,3-triazole analogues as novel fat mass and obesity-associated protein (FTO) inhibitors were synthesised in this study. Among all 1,2,3-triazoles, compound C6 exhibited the most robust inhibition of FTO with an IC50 value of 780 nM. It displayed the potent antiproliferative activity against KYSE-150, KYSE-270, TE-1, KYSE-510, and EC109 cell lines with IC50 value of 2.17, 1.35, 0.95, 4.15, and 0.83 μM, respectively. In addition, C6 arrested the cell cycle at G2 phase against TE-1 and EC109 cells in a concentration-dependent manner. Analysis of cellular mechanisms demonstrated that C6 concentration-dependently regulated epithelial mesenchymal transition (EMT) pathway and PI3K/AKT pathway against TE-1 and EC109 cells. Molecular docking studies that C6 formed important hydrogen-bond interaction with Lys107, Asn110, Tyr108, and Leu109 of FTO. These findings suggested that C6 as a novel FTO inhibitor and orally antitumor agent deserves further investigation to treat esophageal cancer.  相似文献   
85.
不同施肥处理对土壤水稳定性团聚体及有机碳分布的影响   总被引:38,自引:0,他引:38  
以国家褐潮土16 a的长期肥料试验为平台(北京昌平),研究长期不同施肥对耕层土壤水稳定性团聚体及其有机碳的影响。主要研究结果:与耕种农田土壤相比,长期撂荒(CK0)可以提高水稳定性大团聚体的含量及其有机碳含量和储量。而农田耕作后,破坏了水稳性大团聚体,相应地增加水稳性微团聚体的含量。与长期不施肥种植作物(CK)相比,长期施氮磷钾肥(NPK)、氮磷钾配施有机肥(NPKM)和氮磷钾秸秆还田(NPKS)处理对水稳性团聚体数量分布和平均重量直径(MWD)有显著影响,其中对2mm和0.25 2mm水稳性大团聚体的促进作用最明显,说明施肥处理增加的新碳主要向0.25 2mm和2mm团聚体富集。在不同水平水稳性团聚体中,2mm和0.25 2mm两个级别的水稳性大团聚体有机碳的含量显著高于0.0530.25mm和0.053mm水稳性微团聚体。化肥与有机肥配施(NPKM)处理可提高水稳性大团聚体含量,改善土壤团聚体的结构。长期小麦-玉米→小麦-大豆复种轮作并施氮磷钾化肥的处理(NPKF)各级团聚体中有机碳的含量高于长期小麦-玉米轮作并施氮磷钾化肥的处理(NPK)。  相似文献   
86.
一种多聚羟基烷酸产生菌的诱变育种   总被引:6,自引:0,他引:6  
以野生型自养黄杆菌为出发菌株,经亚硝酸、紫外线、60Coγ射线诱变处理选得三株性状优良的突变株(Uγ-、Uγ-17、Uγ-20)。Uγ-1突变株的菌落形态为菊花形,白色。Uγ-17和Uγ-20突变株的菌落形态均为圆凸光滑型,微黄色。40h的摇瓶发酵结果表明,Uγ-1、Uγ-17、Uγ-20突变株的干细胞产量分别为8.1g/1、11.2g/1、10.5g/1,其产物对干细胞的得率系数(yp/x)分别为0.74、0.75、0.79。与野生型菌株相比,这些突变株的干细胞产量yp/x分别增加  相似文献   
87.
Pain is a multidimensional perception that includes unpleasant somatosensory and affective experiences; however, the underlying neural circuits that mediate different components of pain remain elusive. Although hyperactivity of basolateral amygdala glutamatergic (BLAGlu) neurons is required for the somatosensory and emotional processing of pain, the precise excitatory inputs to BLAGlu neurons and their roles in mediating different aspects of pain are unclear. Here, we identified two discrete glutamatergic neuronal circuits in male mice: a projection from the insular cortex glutamatergic (ICGlu) to BLAGlu neurons, which modulates both the somatosensory and affective components of pain, and a projection from the mediodorsal thalamic nucleus (MDGlu) to BLAGlu neurons, which modulates only the aversive-affective component of pain. Using whole-cell recording and fiber photometry, we found that neurons within the IC→BLA and MD→BLA pathways were activated in mice upon inflammatory pain induced by injection of complete Freund’s adjuvant (CFA) into their paws. Optical inhibition of the ICGlu→BLA pathway increased the nociceptive threshold and induced behavioral place preference in CFA mice. In contrast, optical inhibition of the MDGlu→BLA pathway did not affect the nociceptive threshold but still induced place preference in CFA mice. In normal mice, optical activation of the ICGlu→BLA pathway decreased the nociceptive threshold and induced place aversion, while optical activation of the MDGlu→BLA pathway only evoked aversion. Taken together, our results demonstrate that discrete ICGlu→BLA and MDGlu→BLA pathways are involved in modulating different components of pain, provide insights into its circuit basis, and better our understanding of pain perception.  相似文献   
88.
Symbiotic microbes play a crucial role in regulating parasite–host interactions; however, the role of bacterial associates in parasite–host interactions requires elucidation. In this study, we showed that, instead of introducing numerous symbiotic bacteria, dispersal of 4th-stage juvenile (JIV) pinewood nematodes (PWNs), Bursaphelenchus xylophilus, only introduced few bacteria to its vector beetle, Monochamus alternatus (Ma). JIV showed weak binding ability to five dominant bacteria species isolated from the beetles’ pupal chamber. This was especially the case for binding to the opportunistic pathogenic species Serratia marcescens; the nematodes’ bacteria binding ability at this critical stage when it infiltrates Ma for dispersal was much weaker compared with Caenorhabditis elegans, Diplogasteroides asiaticus, and propagative-stage PWN. The associated bacterium S. marcescens, which was isolated from the beetles’ pupal chambers, was unfavorable to Ma, because it caused a higher mortality rate upon injection into tracheae. In addition, S. marcescens in the tracheae caused more immune effector disorders compared with PWN alone. Ma_Galectin2 (MaGal2), a pattern-recognition receptor, was up-regulated following PWN loading. Recombinant MaGal2 protein formed aggregates with five dominant associated bacteria in vitro. Moreover, MaGal2 knockdown beetles had up-regulated prophenoloxidase gene expression, increased phenoloxidase activity, and decreased PWN loading. Our study revealed a previously unknown strategy for immune evasion of this plant pathogen inside its vector, and provides novel insights into the role of bacteria in parasite–host interactions.  相似文献   
89.
本文介绍一种提取和提纯隐球菌DNA的方法。将蜗牛酶消化后所得的原生质体,用SE液反复洗涤以除去夹膜多糖,并用55℃热处理裂解原生质体,使DNA的提取和提纯得到了满意的结果。每克湿菌可获得600μg以上的DNA,而且所得的DNA样品特别适合于用T_(?)法测定DNA G+以C mol%含量。  相似文献   
90.
As one of the most important daily motor activities, human locomotion has been investigated intensively in recent decades. The locomotor functions and mechanics of human lower limbs have become relatively well understood. However, so far our understanding of the motions and functional contributions of the human spine during locomotion is still very poor and simultaneous in-vivo limb and spinal column motion data are scarce. The objective of this study is to investigate the delicate in-vivo kinematic coupling between different functional regions of the human spinal column during locomotion as a stepping stone to explore the locomotor function of the human spine complex. A novel infrared reflective marker cluster system was constrncted using stereophotogrammetry techniques to record the 3D in-vivo geometric shape of the spinal column and the segmental position and orientation of each functional spinal region simultaneously. Gait measurements of normal walking were conducted. The preliminary results show that the spinal column shape changes periodically in the frontal plane during locomotion. The segmental motions of different spinal functional regions appear to be strongly coupled, indicating some synergistic strategy may be employed by the human spinal column to facilitate locomotion. In contrast to traditional medical imaging-based methods, the proposed technique can be used to investigate the dynamic characteristics of the spinal column, hence providing more insight into the functional biomechanics of the human spine.  相似文献   
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