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ObjectivesIn December 2019, coronavirus disease 2019 (COVID-19) emerged in Wuhan City and rapidly spread across the world. The clinical characteristics of affected patients in different regions and populations may differ. Thus, this study aimed to identify the characteristics of the disease to provide an insight about the prevention and treatment of COVID-19.MethodsData on the demographic characteristics and clinical findings of the patients admitted at the First Hospital of Changsha from January 1, 2020 to February 10, 2020 were assessed.ResultsIn this study, there were 8 (3.8%) asymptomatic, 21 (10.0%) mild upper respiratory tract infection (URTI), and 180 (86.1%) pneumonia cases. In total, 47 (22.5%) patients resided in Wuhan, and 45 (21.5%) had recently traveled to Wuhan before disease onset. Moreover, 19 (9.1%) had contact with people from Wuhan, and 69 (33.0%) were family cluster cases. The median incubation period was approximately 6.3 (range: 1.0–20.0) days. Fever and cough were the most common initial symptoms: 99 (49.3%) patients presented with fever, without cough; 59 (29.4%) with cough, without fever; and 33 (16.4%) with both fever and cough.ConclusionThe symptoms of patients with COVID-19 were relatively mild outside Wuhan, and family cluster was a remarkable epidemic characteristic. Special attention should be paid to asymptomatic patients.  相似文献   
244.
Bladder cancer is one of the most common malignant tumors in the urinary system. The development and improvement of treatment efficiency require the deepening of the understanding of its molecular mechanism. This study investigated the role of ALPK2, which is rarely studied in malignant tumors, in the development of bladder cancer. Our results showed the upregulation of ALPK2 in bladder cancer, and data mining of TCGA database showed the association between ALPK2 and pathological parameters of patients with bladder cancer. In vitro and in vivo experiments demonstrated that knockdown of ALPK2 could inhibit bladder cancer development through regulating cell proliferation, cell apoptosis, and cell migration. Additionally, DEPDC1A is identified as a potential downstream of ALPK2 with direct interaction, whose overexpression/downregulation can inhibit/promote the malignant behavioral of bladder cancer cells. Moreover, the overexpression of DEPDC1A can rescue the inhibitory effects of ALPK2 knockdown on bladder cancer. In conclusion, ALPK2 exerts a cancer-promoting role in the development of bladder cancer by regulating DEPDC1A, which may become a promising target to improve the treatment strategy of bladder cancer.Subject terms: Cancer models, Bladder cancer  相似文献   
245.
The purpose of this study was to explore the association between human leukocyte antigens (HLA)-A, -B, -C, -DRB1 and -DQB1 allele polymorphisms and different hematological diseases in Chinese groups. Retrospective analyses of HLA genotyping data in high-resolution for patients with acute myeloid leukemia (AML, 766 cases), chronic myeloid leukemia (CML, 330 cases), acute lymphoblastic leukemia (ALL, 605 cases), aplastic anemia (AA, 229 cases), myelodysplastic syndrome (MDS, 204 cases) were performed, and the susceptible or protective HLA alleles of the above-mentioned diseases were analyzed by Chi-square test and Fisher exact test with unrelated hematopoietic stem cell donors as control. The Results indicated that A*0201, B*4402, C*0701, DRB1*1201, DRB1*1401, and DQB1*0602 might be susceptible genes of AML, while A*1101, A*3303, B*5801, C*0302, DRB1*0301, DQB1*0201 and DQB1*0502 might be protective genes of AML. A*3303 might be a protective gene of CML, and DRB1*1401 might be a susceptible gene of CML. ALL's susceptible genes included A*0201, A*0210, B*5201, DRB1*1201, DRB1*1401 and DQB1*0602, but its protective genes included DQB1*0502. For AA, A*0201, A*0206, B*1511, DRB1*0901, DRB1*1401, DQB1*0303, DQB1*0602 might be susceptible genes, while A*3303, B*5801, C*0302, DRB1*1602 and DQB1*0502 might be protective genes. A*0201, A*0206, B*1511, DRB1*0901, DRB1*1401, DQB1*0303. A*0201, B*1558, B*4801, B*5201, DRB1*1401, DRB1*1501, and DQB1*0602 might be susceptible genes of MDS, and A*3303, B*4601, B*5801, C*0302, and DRB1*0901 might be protective genes of MDS. On the basis of HLA high-resolution genotyping for the first time, this study comprehensively analyzed HLA alleles associated with different hematological diseases in the Chinese population, which should provide clues for further study on the pathogenesis of these diseases.  相似文献   
246.
我国农作物重大迁飞性害虫发生为害及监测预报技术   总被引:1,自引:0,他引:1  
文章概述了我国一类农作物病虫害中7种(类)迁飞性害虫发生为害概况,即是我国三大粮食作物上为害最为严重的害虫,发生区域涵盖我国粮食作物种植区,且存在国内外虫源交流;概述了成虫种群监测、雌蛾卵巢发育分级、翅型调查、异地预报等迁飞性害虫监测预报技术;提出了需要对迁飞性害虫成灾机理、智能化监测工具和迁飞关键路径进行研究,努力建成全国空天地一体化监测网络,实现迁飞性害虫的精准预报的建议.  相似文献   
247.
Signaling through the mammalian target of rapamycin (mTOR) in response to amino acid availability controls many cellular and developmental processes. mTOR is a master regulator of myogenic differentiation, but the pathways mediating amino acid signals in this process are not known. Here we examine the Rag GTPases and the class III phosphoinositide 3-kinase (PI3K) Vps34, two mediators of amino acid signals upstream of mTOR complex 1 (mTORC1) in cell growth regulation, for their potential involvement in myogenesis. We find that, although both Rag and Vps34 mediate amino acid activation of mTORC1 in C2C12 myoblasts, they have opposing functions in myogenic differentiation. Knockdown of RagA/B enhances, whereas overexpression of active RagB/C mutants impairs, differentiation, and this inhibitory function of Rag is mediated by mTORC1 suppression of the IRS1-PI3K-Akt pathway. On the other hand, Vps34 is required for myogenic differentiation. Amino acids activate a Vps34-phospholipase D1 (PLD1) pathway that controls the production of insulin-like growth factor II, an autocrine inducer of differentiation, through the Igf2 muscle enhancer. The product of PLD, phosphatidic acid, activates the enhancer in a rapamycin-sensitive but mTOR kinase–independent manner. Our results uncover amino acid–sensing mechanisms controlling the homeostasis of myogenesis and underline the versatility and context dependence of mTOR signaling.  相似文献   
248.
Genetic linkage maps of Fenneropenaeus chinensis were constructed using a “double pseudo-testcross” strategy with 200 single nucleotide polymorphisms (SNPs) markers. This study represents the first SNP genetic linkage map for F. chinensis. The parents and F 1 progeny of 100 individuals were used as mapping populations. 21 genetic linkage groups in the male and female maps were identified. The male linkage map was composed of 115 loci and spanned 879.7 cM, with an average intermarker spacing of 9.4 cM, while the female map was composed of 119 loci and spanned 876.2 cM, with an average intermarker spacing of 8.9 cM. The estimated coverage of the linkage maps was 51.94% for the male and 53.77% for the female, based on two estimates of genome length. The integrated map contains 180 markers distributed in 16 linkage groups, and spans 899.3 cM with an average marker interval of 5.2 cM. This SNP genetic map lays the foundation for future shrimp genomics and genetic breeding studies, especially the discovery of gene or regions for economically important traits in Chinese shrimp.  相似文献   
249.
Transforming growth factor-β (TGF-β) is known to promote tumor migration and invasion. Bone morphogenetic proteins (BMPs) are members of the TGF-β family expressed in a variety of human carcinoma cell lines. The role of bone morphogenetic protein 9 (BMP9), the most powerful osteogenic factor, in osteosarcoma (OS) progression has not been fully clarified. The expression of BMP9 and its receptors in OS cell lines was analyzed by RT-PCR. We found that BMP9 and its receptors were expressed in OS cell lines. We further investigated the influence of BMP9 on the biological behaviors of OS cells. BMP9 overexpression in the OS cell lines 143B and MG63 inhibited in vitro cell migration and invasion. We further investigated the expression of a panel of cancer-related genes and found that BMP9 overexpression increased the phosphorylation of Smad1/5/8 proteins, increased the expression of ID1, and reduced the expression and activity of matrix metalloproteinase 9 (MMP9) in OS cells. BMP9 silencing induced the opposite effects. We also found that BMP9 may not affect the chemokine (C-X-C motif) ligand 12 (CXCL12)/C-X-C chemokine receptor type 4 (CXCR4) axis to regulate the invasiveness and metastatic capacity of OS cells. Interestingly, CXCR4 was expressed in both 143B and MG63 cells, while CXCL12 was only detected in MG63 cells. Taken together, we hypothesize that BMP9 inhibits the migration and invasiveness of OS cells through a Smad-dependent pathway by downregulating the expression and activity of MMP9.  相似文献   
250.
Sleep adaptation in an unfamiliar environment, the so-called “first-night effect”, is known to occur in healthy individuals. To avoid the confounding effects of the “first-night effect”, the first-night sleep data are not used in most of sleep studies. In the present study, we examined changes of sleep adaptation in hospitalized patients with depression. Polysomnographic recordings were obtained for two consecutive nights from 14 patients, and sleep parameters were compared between both nights. Total sleep time, sleep latency, awakening times, movement awakening time, sleep efficiency, sleep architecture, rapid eye movement (REM) sleep latency, REM intensity, REM density, REM time, REM cycles, and other indicators showed no significant difference (p > 0.05) between the first and second nights. To conclude, hospitalized patients with depression have relatively less change in sleep adaptation, thus, the data from their first night do not need to be discarded.  相似文献   
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