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61.
盘鮈属鱼类的分类研究及两新种记述(鲤形目:鲤科) 总被引:2,自引:2,他引:0
盘鮈属是我国鲤科鱼类的一个特有属,过去已记录7种,因早期发表的云南盘鮈原始描述简略,国内又无人察看过模式标本,造成一些种名归属混乱。本工作在核对多数种的模式标木或地模标本的基础上,对盘鮈属鱼类的分类性状重新估价,认为多鳞盘鮈 D.polylepis Huang不能成立,为长鳔盘鮈 D.macrophysallidos Huang的同物异名,予以归并,经整理本属鱼类可分为8个种,其中具2个新种,文中给出了分种检索表,还就过去分类中存在的其他问题进行了讨论。 相似文献
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XING LI GUO HONG XIA JIAN FEI FANG HUANG LI HE GUO Institute of Biochemistry Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China 《Cell research》2001,(2)
INTRODUCTIONGal a(1, 3) Gal (gal epitope) is a carbohydrate epitope, which is produced in large amounton the cells of pigs, mice and New World monkey(monkey of South America) by the glycosylationenzyme G alal 1 ) 4G IcNAc3- a- D- galactosyltransferase[or(1, 3)GT; EC2.4.1.511111. This enzyme is active in the Golgi appaxatus of cells and transfers galactose from the sugandonor uridine diphoSphate galactose (UDP-galactose) to the acceptor Nacetyllactosamine residue (Galaal-4GlcNAc-R… 相似文献
63.
《生物工程学报》编辑部 《生物工程学报》2010,26(2):140-140
<正>焦瑞身(Jui-shen Chiao)1918-09-13,2009年12月22日卒于上海。1936年考取清华大学化学系,1941年毕业于西南联合大学并留校任化学系助教。1946年在北京大学农学院农化系任助教。 相似文献
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Marcelo U. Ferreira Isabel Giacomini Priscila M. Sato Barbara H. Loureno Vanessa C. Nicolete Lewis F. Buss Alicia Matijasevich Marcia C. Castro Marly A. Cardoso for the MINA-Brazil Working Group 《PLoS neglected tropical diseases》2022,16(7)
BackgroundThe epidemiology of childhood SARS-CoV-2 infection and COVID-19-related illness remains little studied in high-transmission tropical settings, partly due to the less severe clinical manifestations typically developed by children and the limited availability of diagnostic tests. To address this knowledge gap, we investigate the prevalence and predictors of SARS-CoV-2 infection (either symptomatic or not) and disease in 5 years-old Amazonian children.Methodology/Principal findingsWe retrospectively estimated SARS-CoV-2 attack rates and the proportion of infections leading to COVID-19-related illness among 660 participants in a population-based birth cohort study in the Juruá Valley, Amazonian Brazil. Children were physically examined, tested for SARS-CoV-2 IgG and IgM antibodies, and had a comprehensive health questionnaire administered during a follow-up visit at the age of 5 years carried out in January or June-July 2021. We found serological evidence of past SARS-CoV-2 infection in 297 (45.0%; 95% confidence interval [CI], 41.2–48.9%) of 660 cohort participants, but only 15 (5.1%; 95% CI, 2.9–8.2%) seropositive children had a prior medical diagnosis of COVID-19 reported by their mothers or guardians. The period prevalence of clinically apparent COVID-19, defined as the presence of specific antibodies plus one or more clinical symptoms suggestive of COVID-19 (cough, shortness of breath, and loss of taste or smell) reported by their mothers or guardians since the pandemic onset, was estimated at 7.3% (95% CI, 5.4–9.5%). Importantly, children from the poorest households and those with less educated mothers were significantly more likely to be seropositive, after controlling for potential confounders by mixed-effects multiple Poisson regression analysis. Likewise, the period prevalence of COVID-19 was 1.8-fold (95%, CI 1.2–2.6-fold) higher among cohort participants exposed to food insecurity and 3.0-fold (95% CI, 2.8–3.5-fold) higher among those born to non-White mothers. Finally, children exposed to household and family contacts who had COVID-19 were at an increased risk of being SARS-CoV-2 seropositive and–even more markedly–of having had clinically apparent COVID-19 by the age of 5 years.Conclusions/SignificanceChildhood SARS-CoV-2 infection and COVID-19-associated illness are substantially underdiagnosed and underreported in the Amazon. Children in the most socioeconomically vulnerable households are disproportionately affected by SARS-CoV-2 infection and disease. 相似文献
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David M. Gordon David Cunningham Gloria Zender Patrick J. Lawrence Jacqueline S. Penaloza Hui Lin Sara M. Fitzgerald-Butt Katherine Myers Tiffany Duong Donald J. Corsmeier Jeffrey B. Gaither Harkness C. Kuck Saranga Wijeratne Blythe Moreland Benjamin J. Kelly Baylor-Johns Hopkins Center for Mendelian Genomics Vidu Garg Peter White Kim L. McBride 《PLoS genetics》2022,18(6)
Congenital heart disease (CHD) is a common group of birth defects with a strong genetic contribution to their etiology, but historically the diagnostic yield from exome studies of isolated CHD has been low. Pleiotropy, variable expressivity, and the difficulty of accurately phenotyping newborns contribute to this problem. We hypothesized that performing exome sequencing on selected individuals in families with multiple members affected by left-sided CHD, then filtering variants by population frequency, in silico predictive algorithms, and phenotypic annotations from publicly available databases would increase this yield and generate a list of candidate disease-causing variants that would show a high validation rate. In eight of the nineteen families in our study (42%), we established a well-known gene/phenotype link for a candidate variant or performed confirmation of a candidate variant’s effect on protein function, including variants in genes not previously described or firmly established as disease genes in the body of CHD literature: BMP10, CASZ1, ROCK1 and SMYD1. Two plausible variants in different genes were found to segregate in the same family in two instances suggesting oligogenic inheritance. These results highlight the need for functional validation and demonstrate that in the era of next-generation sequencing, multiplex families with isolated CHD can still bring high yield to the discovery of novel disease genes. 相似文献
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Water striders are insects living on the water surface, over which they can move very quickly and rarely get wetted. We measured the force of free walking in water striders, using a hair attached to their backs and a 3D strain gauge. The error was calculated by comparing force and data derived from geometry and was estimated as 13%. Females on average were stronger (1.32 mN) than males (0.87 mN), however, the ratio of force to weight was not significantly different. Compared with other lighter species, Aquarius paludum seems stronger, but the ratio of force to weight is actually lower. A. paludum applies about 0.3 mN·cm-1 to 0.4 mN·cm-1 with its mid-legs, thus avoiding penetrating the surface tension layer while propelling itself rapidly over the water surface.We also investigated the external morphology with SEM. The body is covered by effectively two layers of macro-and micro-hairs, which renders them hydrophobic. The setae are long (40 um-60 um) and stiff, being responsible for waterproofing, and the microtrichia are much smaller (<10 um), slender, and flexible, holding a bubble over the body when submerged. 相似文献
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Tazeen Hasan Jafar Ngiap Chuan Tan Rupesh Madhukar Shirore John Carson Allen Eric Andrew Finkelstein Siew Wai Hwang Agnes Ying Leng Koong Peter Kirm Seng Moey Gary Chun-Yun Kang Chris Wan Teng Goh Reena Chandhini Subramanian Anandan Gerard Thiagarajah Chandrika Ramakrishnan Ching Wee Lim Jianying Liu for SingHypertension Study Group 《PLoS medicine》2022,19(6)
BackgroundDespite availability of clinical practice guidelines for hypertension management, blood pressure (BP) control remains sub-optimal (<30%) even in high-income countries. This study aims to assess the effectiveness of a potentially scalable multicomponent intervention integrated into primary care system compared to usual care on BP control.Methods and findingsA cluster-randomized controlled trial was conducted in 8 government clinics in Singapore. The trial enrolled 916 patients aged ≥40 years with uncontrolled hypertension (systolic BP (SBP) ≥140 mmHg or diastolic BP (DBP) ≥90 mmHg).Multicomponent intervention consisted of physician training in risk-based treatment of hypertension, subsidized losartan-HCTZ single-pill combination (SPC) medications, nurse training in motivational conversations (MCs), and telephone follow-ups. Usual care (controls) comprised of routine care in the clinics, no MC or telephone follow-ups, and no subsidy on SPCs. The primary outcome was mean SBP at 24 months’ post-baseline. Four clinics (447 patients) were randomized to intervention and 4 (469) to usual care. Patient enrolment commenced in January 2017, and follow-up was during December 2018 to September 2020. Analysis used intention-to-treat principles. The primary outcome was SBP at 24 months. BP at baseline, 12 and 24 months was modeled at the patient level in a likelihood-based, linear mixed model repeated measures analysis with treatment group, follow-up, treatment group × follow-up interaction as fixed effects, and random cluster (clinic) effects.A total of 766 (83.6%) patients completed 2-year follow-up. A total of 63 (14.1%) and 87 (18.6%) patients in intervention and in usual care, respectively, were lost to follow-up. At 24 months, the adjusted mean SBP was significantly lower in the intervention group compared to usual care (−3.3 mmHg; 95% CI: −6.34, −0.32; p = 0.03). The intervention led to higher BP control (odds ratio 1.51; 95% CI: 1.10, 2.09; p = 0.01), lower odds of high (>20%) 10-year cardiovascular risk score (OR 0.67; 95% CI: 0.47, 0.97; p = 0.03), and lower mean log albuminuria (−0.22; 95% CI: −0.41, −0.02; p = 0.03). Mean DBP, mortality rates, and serious adverse events including hospitalizations were not different between groups. The main limitation was no masking in the trial.ConclusionsA multicomponent intervention consisting of physicians trained in risk-based treatment, subsidized SPC medications, nurse-delivered motivational conversation, and telephone follow-ups improved BP control and lowered cardiovascular risk. Wide-scale implementation of a multicomponent intervention such as the one in our trial is likely to reduce hypertension-related morbidity and mortality globally.Trial registrationTrial Registration: Clinicaltrials.gov .Tazeen H Jafar and colleagues present findings from a cluster-randomized controlled trial conducted to evaluate the effectiveness of an intervention designed to manage hypertension. NCT02972619相似文献
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