期刊文献+
共找到57,810篇文章
< 1 2 250 >
每页显示 20 50 100
Subtotal colonic bypass plus colostomy with antiperistaltic cecoproctostomy for the treatment of slow transit constipation in an aged population:A retrospective control study 被引量:4
1
作者 Yang Yang Yong-Li Cao +3 位作者 Wen-Hang Wang Yuan-Yao Zhang Nan Zhao Dong Wei 《World Journal of Gastroenterology》 SCIE CAS 2018年第23期2491-2500,共10页
AIM To compare the efficacy,improved quality of life,and prognosis in patients undergoing either subtotal colonic bypass with antiperistaltic cecoproctostomy(SCBAC) or subtotal colonic bypass plus colostomy with antip... AIM To compare the efficacy,improved quality of life,and prognosis in patients undergoing either subtotal colonic bypass with antiperistaltic cecoproctostomy(SCBAC) or subtotal colonic bypass plus colostomy with antiperistaltic cecoproctostomy(SCBCAC) for the treatment of slow transit constipation.METHODS Between October 2010 and October 2014,aged patients with slow transit constipation who were hospitalized and underwent laparoscopic surgery in our institute weredivided into two groups: the bypass group,15 patients underwent SCBAC,and the bypass plus colostomy group,14 patients underwent SCBCAC. The following preoperative and postoperative clinical data were collected: gender,age,body mass index,operative time,first flatus time,length of hospital stay,bowel movements(BMs),Wexner fecal incontinence scale,Wexner constipation scale(WCS),gastrointestinal quality of life index(GIQLI),numerical rating scale for pain intensity(NRS),abdominal bloating score(ABS),and ClavienDindo classification of surgical complications(CD) before surgery and at 3,6,12,and 24 mo after surgery.RESULTS All patients successfully underwent laparoscopic surgery without open surgery conversion or surgeryrelated death. The operative time and blood loss were significantly less in the bypass group than in the bypass plus colostomy group(P = 0.007). No significant differences were observed in first flatus time,length of hospital stay,or complications with CD > 1 between the two groups. No patients had fecal incontinence after surgery. At 3,6,and 12 mo after surgery,the number of BMs was significantly less in the bypass plus colostomy group than in the bypass group. The parameters at 3,6,12,and 24 mo after surgery in both groups significantly improved compared with the preoperative conditions(P < 0.05),except NRS at 3,6 mo after surgery in both groups,ABS at 12,24 mo after surgery and NRS at 12,24 mo after surgery in the bypass group. WCS,GIQLI,NRS,and ABS significantly improved in the bypass plus colostomy group compared with the bypass group at 3,6,12,and 24 mo after surgery(P < 0.05) except WCS,NRS at 3,6 mo after surgery and ABS at 3 mo after surgery. At 1 year after surgery,a barium enema examination showed that the emptying time was significantly better in the bypass plus colostomy group than in the bypass group(P = 0.007).CONCLUSION Laparoscopic SCBCAC is an effective and safe procedure for the treatment of slow transit constipation in an aged population and can significantly improve the prognosis. Its clinical efficacy is more favorable compared with that of SCBAC. Laparoscopic SCBCAC is a better procedure for the treatment of slow transit constipation in an aged population. 展开更多
关键词 SUBTOTAL COLONIC BYPASS plus COLOSTOMY with antiperistaltic cecoproctostomy SUBTOTAL COLONIC BYPASS with antiperistaltic cecoproctostomy Minimally invasive surgery for treatment of CONSTIPATION Clinical efficacy Slow transit CONSTIPATION in an aged population
下载PDF
Association of G-protein coupled purinergic receptor P2Y2 with ischemic stroke in a Han Chinese population of North China 被引量:2
2
作者 Li-Ying Yuan Zhi-Yi He +1 位作者 Lei Li Yan-Zhe Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第3期506-512,共7页
The G-protein-coupled purinergic receptor P2Y2(P2RY2) plays an important role in the mechanism of atherosclerosis, which is relevant to ischemic stroke. This retrospective case-control study aimed to assess the relati... The G-protein-coupled purinergic receptor P2Y2(P2RY2) plays an important role in the mechanism of atherosclerosis, which is relevant to ischemic stroke. This retrospective case-control study aimed to assess the relationship between P2RY2 gene polymorphisms and ischemic stroke risk in the northern Han Chinese population. In this study, clinical data and peripheral blood specimens were collected from 378 ischemic stroke patients and 344 controls. The ischemic stroke participants were recruited from the First Affiliated Hospital of China Medical University and the First Affiliated Hospital of Liaoning Medical University. The controls were recruited from the Health Check Center at the First Affiliated Hospital of China Medical University. Ischemic stroke patients were divided into two subgroups according to the Trial of ORG 10172 in Acute Stroke Treatment(TOAST) classification: large-artery atherosclerosis(n = 178) and small-artery occlusion(n = 200) strokes. All subjects were genotyped for three single nucleotide polymorphisms(rs4944831, rs1783596, and rs4944832) in the P2RY2 gene using peripheral venous blood samples. The distribution of the dominant rs4944832 phenotype(GG vs. GA+AA) differed significantly between small-artery occlusion patients and control subjects(odds ratio(OR) = 1.720, 95% confidence interval(CI): 1.203–2.458, P < 0.01). Multivariable logistic regression analysis revealed that the GG genotype of rs4944832 was significantly more prevalent in small-artery occlusion patients than in control subjects(OR = 1.807, 95% CI: 1.215–2.687, P < 0.01). The overall distribution of the haplotype established by rs4944831-rs1783596-rs4944832 was significantly different between ischemic stroke patients and controls(P < 0.01). In ischemic stroke patients, the frequency of the G-C-G haplotype was significantly higher than in control subjects(P = 0.028), whereas the frequency of the T-C-A haplotype was lower than in control subjects(P = 0.047). These results indicate that the G-C-G haplotype of P2RY2 is a susceptibility haplotype for ischemic stroke. In addition, the GG genotype of rs4944832 may be associated with the development of small-artery occlusion in the northern Han Chinese population. The study protocol was approved by the Ethics Committee of the First Affiliated Hospital of China Medical University on February 20, 2012(No. 2012-38-1) and the First Affiliated Hospital of Liaoning Medical University, China, on March 1, 2013(No. 2013-03-1). All participants gave their informed consent. This trial was registered with the ISRCTN Registry(ISRCTN11439124) on October 24, 2018. Protocol version(1.0). 展开更多
关键词 nerve REGENERATION P2RY2 GENE ischemic stroke single nucleotide polymorphism CASE-CONTROL study haplotype northern Han Chinese population large-artery atherosclerosis small-artery occlusion hypertension candidate GENE neural REGENERATION
下载PDF
Association between PPARG genetic polymorphisms and ischemic stroke risk in a northern Chinese Han population: a case-control study 被引量:14
3
作者 Yan-Zhe Wang He-Yu Zhang +3 位作者 Fang Liu Lei Li Shu-Min Deng Zhi-Yi He 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第11期1986-1993,共8页
Two common polymorphisms of the peroxisome proliferator-activated receptor gamma(PPARG) gene, rs1801282 and rs3856806, may be important candidate gene loci affecting the susceptibility to ischemic stroke. This case-co... Two common polymorphisms of the peroxisome proliferator-activated receptor gamma(PPARG) gene, rs1801282 and rs3856806, may be important candidate gene loci affecting the susceptibility to ischemic stroke. This case-control study sought to identify the relationship between these two single-nucleotide polymorphisms and ischemic stroke risk in a northern Chinese Han population. A total of 910 ischemic stroke participants were recruited from the First Hospital of China Medical University, Shenyang, China as a case group, of whom 895 completed the study. The 883 healthy controls were recruited from the Health Check Center of the First Hospital of China Medical University, Shenyang, China. All participants or family members provided informed consent. The study protocol was approved by the Ethics Committee of the First Hospital of China Medical University, China on February 20, 2012(approval No. 2012-38-1). The protocol was registered with the Chinese Clinical Trial Registry(registration number: ChiCTR-COC-17013559). Plasma genomic DNA was extracted from all participants and analyzed for rs1801282 and rs3856806 single nucleotide polymorphisms using a SNaPshot Multiplex sequencing assay. Odds ratios(ORs) and 95% confidence intervals(CIs) were calculated using unconditional logistic regression to estimate the association between ischemic stroke and a particular genotype. Results demonstrated that the G allele frequency of the PPARG gene rs1801282 locus was significantly higher in the case group than in the control group(P < 0.001). Individuals carrying the G allele had a 1.844 fold increased risk of ischemic stroke(OR = 1.844, 95% CI: 1.286–2.645, P < 0.001). Individuals carrying the rs3856806 T allele had a 1.366 fold increased risk of ischemic stroke(OR = 1.366, 95% CI: 1.077–1.733, P = 0.010). The distribution frequencies of the PPARG gene haplotypes rs1801282-rs3856806 in the control and case groups were determined. The frequency of distribution in the G-T haplotype case group was significantly higher than that in the control group. The risk of ischemic stroke increased to 2.953 times in individuals carrying the G-T haplotype(OR = 2.953, 95% CI: 2.082–4.190, P < 0.001). The rs1801282 G allele and rs3856806 T allele had a multiplicative interaction(OR = 3.404, 95% CI: 1.631–7.102, P < 0.001) and additive interaction(RERI = 41.705, 95% CI: 14.586–68.824, AP = 0.860;95% CI: 0.779–0.940;S = 8.170, 95% CI: 3.772–17.697) on ischemic stroke risk, showing a synergistic effect. Of all ischemic stroke cases, 86% were attributed to the interaction of the G allele of rs1801282 and the T allele of rs3856806. The effect of the PPARG rs1801282 G allele on ischemic stroke risk was enhanced in the presence of the rs3856806 T allele(OR = 8.001 vs. 1.844). The effect of the rs3856806 T allele on ischemic stroke risk was also enhanced in the presence of the rs1801282 G allele(OR = 2.546 vs. 1.366). Our results confirmed that the G allele of the PPARG gene rs1801282 locus and the T allele of the rs3856806 locus may be independent risk factors for ischemic stroke in the Han population of northern China, with a synergistic effect between the two alleles. 展开更多
关键词 nerve REGENERATION STROKE cerebral ischemia ISCHEMIC STROKE PEROXISOME proliferator-activated receptor γ single-nucleotide polymorphism haplotype analysis interaction CASE-CONTROL study Chinese Han population neural REGENERATION
下载PDF
ECG is not a reliable predictor of sudden cardiac death in the general population
4
作者 Juliane Theilade Redi Pecini +1 位作者 Jacob L. Marott Gorm B. Jensen 《World Journal of Cardiovascular Diseases》 2013年第2期239-244,共6页
Objectives: To determine the predictive value of the ECG for sudden death in the general population. Design: In the Copenhagen City Heart Study, a randomly selected population sample in Copenhagen, Denmarkhas been fol... Objectives: To determine the predictive value of the ECG for sudden death in the general population. Design: In the Copenhagen City Heart Study, a randomly selected population sample in Copenhagen, Denmarkhas been followed prospectively since 1976. From this population sample, we analyzed ECGs of individuals who had suffered sudden cardiac death (SCD) before the age of 50 years and compared them with ECGs of a randomly selected control individuals from the same population sample. Specific ECG signs that could point toward a condition associated with a risk of SCD were noted. Results: From a total of 18,974 individuals in the cohort, 207 had died at an age younger than 50 years. Among these, 24 persons with SCD were identified. The most prevalent ECG abnormality was QRS fragmentation. We found no ECGs with long or short QTc, Brugada sign or WPW. The prevalence of signs of left ventricular hyper-trophy, early repolarization, or fragmentation was not different from the prevalence of these signs in the control group. Conclusion: In the Copenhagen City Heart Study, the ECG failed to predict SCD in persons who died before the age of 50 years. 展开更多
关键词 SUDDEN Cardiac Death ECG Predictive Value of the ECG General population Prediction of SCD ARRHYTHMIA CARDIOMYOPATHY Ischemic HEART Disease Copenhagen City HEART Study Prospective
下载PDF
Qualitative Properties and Numerical Solution of the Kolmogorov-Fisher Type Biological Population Task with Double Nonlinear Diffusion
5
作者 Dildora Kabulovna Muhamediyeva 《Journal of Applied Mathematics and Physics》 2015年第10期1249-1255,共7页
In the present work we study the global solvability of the Kolmogorov-Fisher type biological population task with double nonlinear diffusion and qualitative properties of the solution of the task based on the self-sim... In the present work we study the global solvability of the Kolmogorov-Fisher type biological population task with double nonlinear diffusion and qualitative properties of the solution of the task based on the self-similar analysis. In additional, in this paper we consider the model of two competing population with dual nonlinear cross-diffusion. 展开更多
关键词 DOUBLE Nonlinearity CROSS-DIFFUSION Biological population A Parabolic System of QUASILINEAR Equations CONVECTIVE Heat Transfer Numerical Solution Iterative Process SELF-SIMILAR Solutions
下载PDF
Bayes Prediction of Future Observables from Exponentiated Populations with Fixed and Random Sample Size
6
作者 Essam K. AL-Hussaini M. Hussein 《Open Journal of Statistics》 2011年第1期24-32,共9页
Bayesian predictive probability density function is obtained when the underlying pop-ulation distribution is exponentiated and subjective prior is used. The corresponding predictive survival function is then obtained ... Bayesian predictive probability density function is obtained when the underlying pop-ulation distribution is exponentiated and subjective prior is used. The corresponding predictive survival function is then obtained and used in constructing 100(1 – ?)% predictive interval, using one- and two- sample schemes when the size of the future sample is fixed and random. In the random case, the size of the future sample is assumed to follow the truncated Poisson distribution with parameter λ. Special attention is paid to the exponentiated Burr type XII population, from which the data are drawn. Two illustrative examples are given, one of which uses simulated data and the other uses data that represent the breaking strength of 64 single carbon fibers of length 10, found in Lawless [40]. 展开更多
关键词 Predictive Density And SURVIVAL Functions One- And Two-Sample Schemes BAYES PREDICTION Exponentiated population. Exponentiated BURR Type XII Distribution Data Of Carbon Fibers
下载PDF
Enterobius vermicularis infection among population of General Mansilla,Argentina
7
作者 Betina C Pezzani Marta C Minvielle +3 位作者 Maria M de Luca María A Córdoba María C Apezteguía Juan A Basualdo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第17期2535-2539,共5页
AIM:To evaluate the relationships between the personal, sociocultural,and environmental characteristics,and the presence or absence of symptoms with the detection of Enterobius vermicularis(E.vermicularis)in a populat... AIM:To evaluate the relationships between the personal, sociocultural,and environmental characteristics,and the presence or absence of symptoms with the detection of Enterobius vermicularis(E.vermicularis)in a population sample in our region(General Mansilla,Province of Buenos Aires,Argentina),by individual and familiar analyses. METHODS:E.verrnicularis was diagnosed in 309 people from 70 family units residing in the urban area and the rural area of the city of General Mansilla.Each of them was surveyed so as to register personal,environmental and sociocultural data.Questions about the presence or absence of anal itch,abdominal pain and sleeping disorder were also asked.Significant associations were determined by square chi tests.Logistic regression models were adjusted by using a backward conditional stepwise method to determine the presence of this parasite in the individuals and in the families. RESULTS:The parasites were found in 29.12%(90/309) of the individuals,with a frequency of 14.28%(20/140) among the heads of the families and of 41.42%(70/169) among the children.The only variables showing a significant association were affiliation,where the risk category was “being the son/daughter of”,and the symptoms were abdominal pain,sleeping disorder,and anal itch.Families with a member infected with parasite were considered Positive Families(PF)and they were 40/70(57.14%),only 5%(2/40)of the PF had 100% of their members infected with the parasite.The logistic regression models applied showed that the risk categories were mainly affiliation(son/daughter) and housing(satisfactory)among others. CONCLUSION:The presence of E.vermiculariswas proved in one third of the studied population.The frequency of families with all their members infected with the parasite was very low.Most of the studied personal,sociocultural, and environmental variables did not turn out to be significantly associated with the presence of the parasite.An association with the category of“son/daughter”and housing classified as“satisfactory”was determined.The latter may be due to the fact that the people living in that category of housing have hygienic practices at home that favour the distribution of the eggs in the environment.The presence of the analysed symptoms was associated with the presence of the parasite, thus strengthening the need of periodical control of the population showing at least one of these symptoms. 展开更多
关键词 Enterobius Abdominal Pain Adult Anal Canal ANIMALS ARGENTINA Child ENTEROBIASIS Family Health Female Humans Male PRURITUS Research Support Non-U.S. Gov't Risk Factors Rural population SANITATION Socioeconomic Factors Urban population
下载PDF
Analyzing Population Density Disparity in China with GIS-automated Regionalization: The Hu Line Revisited 被引量:5
8
作者 WANG Fahui LIU Cuiling XU Yaping 《Chinese Geographical Science》 SCIE CSCD 2019年第4期541-552,共12页
The famous ’Hu Line’, proposed by Hu Huanyong in 1935, divided China into two regions(southeast and northwest) of comparable area size but drastically different in population. However, the classic Hu Line was derive... The famous ’Hu Line’, proposed by Hu Huanyong in 1935, divided China into two regions(southeast and northwest) of comparable area size but drastically different in population. However, the classic Hu Line was derived manually in absence of reliable census data and computational technologies of modern days. It has been subject to criticism of lack of scientific rigor and accuracy. This research uses a GIS-automated regionalization method, termed REDCAP(Regionalization with Dynamically Constrained Agglomerative Clustering and Partitioning), to reconstruct the demarcation line based on the 2010 county-level census data in China. The results show that the logarithmic transformation of population density is a better measure of attributive homogeneity in derived regions than density itself, and produces two regions of nearly identical area size and greater contrast in population. Specifically, the revised Hu Line by Hu Huanyong in 1990 had the southeast region with 94.4% of total population and 42.9% of total land, and our delineation line yields a southeast region with 97.4% population and 50.8% land. Therefore, the population density ratio of the two regions is 27.1 by our line, much higher than the ratio of 22.4 by the Hu Line, and thus outperforms the Hu Line in deriving regions of maximum density contrast with comparable area size. Furthermore, more regions are delineated to further advance our understanding of population distribution disparity in China. 展开更多
关键词 HU LINE regional population density DISPARITY GIS-automated REGIONALIZATION REDCAP (Regionalization with Dynamically Constrained Agglomerative Clustering and Partitioning) China
下载PDF
Analyzing and Projection of Future Bangladesh Population Using Logistic Growth Model
9
作者 Mohammad Sharif Ullah Golam Mostafa +1 位作者 Nusrat Jahan Md. Abdul Hakim Khan 《International Journal of Modern Nonlinear Theory and Application》 2019年第3期53-61,共9页
Bangladesh is a densely populated country than many other countries of the world. The population growth is termed as alarming, however, knowledge of growth in the years to come would be useful in planning for the deve... Bangladesh is a densely populated country than many other countries of the world. The population growth is termed as alarming, however, knowledge of growth in the years to come would be useful in planning for the development of the country. This article is based on the projection of future population growth of the country. The available actual population census data during 1991-2011 of Bangladesh was applied to the application of a non-linear, non-autonomous ordinary differential equation familiar as Verhulst logistic population model with the maximum environmental capability of Bangladesh. Bangladesh will reach its carrying capacity of 245.09 million population in the next 56 years i.e. the year 2067 and then it decreases as S-shaped curve. The article has provided a focus on the changing trends of the growth of the population of Bangladesh. 展开更多
关键词 Logistic Model Carrying Capacity Zero Growth Rate Least Square METHOD 6th Order RK METHOD FUTURE population PROJECTION PARABOLIC Profile
下载PDF
The “3 Genomic Numbers” Discovery: How Our Genome Single-Stranded DNA Sequence Is “Self-Designed” as a Numerical Whole
10
作者 Jean-Claude Perez 《Applied Mathematics》 2013年第10期37-53,共17页
This article proves the existence of a hyper-precise global numerical meta-architecture unifying, structuring, binding and controlling the billion triplet codons constituting the sequence of single-stranded DNA of the... This article proves the existence of a hyper-precise global numerical meta-architecture unifying, structuring, binding and controlling the billion triplet codons constituting the sequence of single-stranded DNA of the entire human genome. Beyond the evolution and erratic mutations like transposons within the genome, it’s as if the memory of a fossil genome with multiple symmetries persists. This recalls the “intermingling” of information characterizing the fractal universe of chaos theory. The result leads to a balanced and perfect tuning between the masses of the two strands of the huge DNA molecule that constitute our genome. We show here how codon populations forming the single-stranded DNA sequences can constitute a critical approach to the understanding of junk DNA function. Then, we suggest revisiting certain methods published in our 2009 book “Codex Biogenesis”. In fact, we demonstrate here how the universal genetic code table is a powerful analytical filter to characterize single-stranded DNA sequences constituting chromosomes and genomes. We can then show that any genomic DNA sequence is featured by three numbers, which characterize it and its 64 codon populations with correlations greater than 99%. The number “1” is common to all sequences, expressing the second law of Chargaff. The other 2 numbers are related to each specific DNA sequence case characterizing life species. For example, the entire human genome is characterized by three remarkable numbers 1, 2, and Phi = 1.618 the golden ratio. Associated with each of these three numbers, we can match three axes of symmetry, then “imagine” a kind of hyperspace formed by these codon populations. Then we revisit the value (3-Phi)/2 which is probably universal and common to both the scale of quarks and atomic levels, balancing and tuning the whole human genome codon population. Finally, we demonstrate a new kind of duality between “form and substance” overlapping the whole human genome: we will show that—simultaneously with the duality between genes and junk DNA—there is a second layer of embedded hidden structure overlapping all the DNA of the whole human genome, dividing it into a second type of duality information/redundancy involving golden ratio proportions. 展开更多
关键词 Genetic Code CODON populations Junk DNA Cancer Genomics Chromosomal Translocations Genomes Diversity Chromosomes Diversity WHOLE Human GENOME DNA SEQUENCE Phi the Golden Ratio Fibonacci NUMBERS Information Theory SYMMETRY Cellular Automata Chargaffs CODON Level SYMMETRY Principle Fractal Self-Similarity e Eulers Number Pi form and Substance Redundancy Encryption
下载PDF
Association mapping of lignin response to Verticillium wilt through an eight-way MAGIC population in Upland cotton 被引量:1
11
作者 TIAN Xiao-min HAN Peng +9 位作者 WANG Jing SHAO Pan-xia AN Qiu-shuang Nurimanguli AINI YANG Qing-yong YOU Chun-yuan LIN Hai-rong ZHU Long-fu PAN Zhen-yuan NIE Xin-hui 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第5期1324-1337,共14页
Lignin metabolism plays a pivotal role in plant defense against pathogens and is always positively correlated as a response to pathogen infection. Thus, understanding resistance genes against plant pathogens depends o... Lignin metabolism plays a pivotal role in plant defense against pathogens and is always positively correlated as a response to pathogen infection. Thus, understanding resistance genes against plant pathogens depends on a genetic analysis of the lignin response. This study used eight Upland cotton lines to construct a multi-parent advanced generation intercross(MAGIC) population(n=280), which exhibited peculiar characteristics from the convergence of various alleles coding for advantageous traits. In order to measure the lignin response to Verticillium wilt(LRVW), the artificial disease nursery(ADN) and rotation nursery(RN) were prepared for MAGIC population planting in four environments. The stem lignin contents were collected, and the LRVW was measured with the lignin value of ADN/RN in each environment, which showed significant variations. We employed 9 323 high-quality single-nucleotide polymorphism(SNP) markers obtained from the Cotton-SNP63K array for genotyping the MAGIC population. The SNPs were distributed through the whole genome with 4.78 SNP/Mb density, ranging from 1.14(ChrA06) to 10.08(ChrD08). In addition, a genome-wide association study was performed using a Mixed Linear Model(MLM) for LRVW. Three stable quantitative trait loci(QTLs), qLRVW-A04, qLRVW-A10, and qLRVW-D05, were identified in more than two environments. Two key candidate genes, Ghi_D05G01046 and Ghi_D05G01221, were selected within the QTLs through the combination of variations in the coding sequence, induced expression patterns, and function annotations. Both genes presented nonsynonymous mutations in coding regions and were strongly induced by Verticillium dahliae. Ghi_D05G01046 encodes a leucine-rich extensin(LRx) protein involved in Arabidopsis cell wall biosynthesis and organization. Ghi_D05G01221 encodes a transcriptional co-repressor novel interactor of novel interactor of jasmonic acid ZIM-domain(JAZ–NINJA), which functions in the jasmonic acid(JA) signaling pathway. In summary, the study creates valuable genetic resources for breeding and QTL mapping and opens up a new perspective to uncover the genetic basis of VW resistance in Upland cotton. 展开更多
关键词 genome-wide association study LIGNIN RESPONSE MAGIC population Upland cotton VERTICILLIUM WILT
下载PDF
Changes in the population structure of Calanus sinicus during summer–autumn in the southern Yellow Sea 被引量:2
12
作者 Yongqiang Shi Song Sun +3 位作者 Chaolun Li Guangtao Zhang Bo Yang Peng Ji 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第8期56-63,共8页
Calanus sinicus is a calanoid copepod widely distributed in coastal waters of China and Japan, and oversummering strategies may have major impacts on their population dynamics which in turn affect local marine food we... Calanus sinicus is a calanoid copepod widely distributed in coastal waters of China and Japan, and oversummering strategies may have major impacts on their population dynamics which in turn affect local marine food web structure. The abundance, stage composition, and sex composition of the planktonic copepod C. sinicus were studied from August to October 2002 in the southern Yellow Sea to understand how its population recovers from the over-summering state. Results showed that C. sinicus had low reproduction in August due to high temperature, except in waters near the Cheju Island with rich food and moderate bottom temperature, but the reproduction rates here decreased in September–October as food availability declined. When temperature dropped in September–October, C. sinicus actively propagated in coastal shallow waters. However, reproduction rates of C. sinicus individuals inhabiting the Yellow Sea Cold Water Mass(YSCWM) remained low during the three months of the study. The percentage of C. sinicus females was high during the reproductive period, which suggests that the sex composition of adult C. sinicus may reflect whether or not the population is in the reproductive mode.Numerous fifth copepodite stage(CV) C. sinicus aggregated in the YSCWM in a suspended developmental stage during the three months of this study, and they potentially served as the parental individuals for population development when conditions became optimal for reproduction later in the year. 展开更多
关键词 CALANUS SINICUS stage COMPOSITION SEX COMPOSITION population structure YELLOW Sea Cold Water Mass life history strategy
下载PDF
Current molecular methods for the detection of hepatitis C virus in high risk group population:A systematic review 被引量:4
13
作者 Rushna Firdaus Kallol Saha +1 位作者 Aritra Biswas Provash Chandra Sadhukhan 《World Journal of Virology》 2015年第1期25-32,共8页
Hepatitis C virus(HCV) is an emerging infection worldwide and the numbers of persons infected are increasing every year. Poor blood transfusion methods along with unsafe injection practices are potential sources for t... Hepatitis C virus(HCV) is an emerging infection worldwide and the numbers of persons infected are increasing every year. Poor blood transfusion methods along with unsafe injection practices are potential sources for the rapid spread of infection. Early detection of HCV is the need of the hour especially in high riskgroup population as these individuals are severely immunocompromised. Enzyme Immunoassays are the most common detection techniques but they provide no evidence of active viremia or identification of infected individuals in the antibody-negative phase and their efficacy is limited in individuals within high risk group population. Molecular virological techniques have an important role in detecting active infection with utmost specificity and sensitivity. Technologies for assessment of HCV antibody and RNA levels have improved remarkably, as well as our understanding of how to best use these tests in patient management. This review aims to give an overview of the different serological and molecular methods employed in detecting HCV infection used nowadays. Additionally, the review gives an insight in the new molecular techniques that are being developed to improve the detection techniques particularly in High Risk Group population who are severely immunocompromised. 展开更多
关键词 Molecular DETECTION Enzyme IMMUNOASSAY High risk group population Nucleic acid amplification assays POLYMERASE chain reaction
下载PDF
Photosynthetic response to a winter heatwave in leading and trailing edge populations of the intertidal red alga Corallina offi-cinalis(Rhodophyta)
14
作者 Regina Kolzenburg Federica Ragazzola +3 位作者 Laura Tamburello Katy R.Nicastro Christopher D.McQuaid Gerardo I.Zardi 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第7期70-77,共8页
Marine heatwaves(MHWs)caused by anthropogenic climate change are becoming a key driver of change at the ecosystem level.Thermal conditions experienced by marine organisms across their distribution,particularly towards... Marine heatwaves(MHWs)caused by anthropogenic climate change are becoming a key driver of change at the ecosystem level.Thermal conditions experienced by marine organisms across their distribution,particularly towards the equator,are likely to approach their physiological limits,resulting in extensive mortality and subsequent changes at the population level.Populations at the margins of their species’distribution are thought to be more sensitive to climate-induced environmental pressures than central populations,but our understanding of variability in fitness-related physiological traits in trailing versus leading-edge populations is limited.In a laboratory simulation study,we tested whether two leading(Iceland)and two trailing(Spain)peripheral populations of the intertidal macroalga Corallina officinalis display different levels of maximum potential quantum efficiency(Fv/Fm)resilience to current and future winter MHWs scenarios.Our study revealed that ongoing and future local winter MHWs will not negatively affect leading-edge populations of C.officinalis,which exhibited stable photosynthetic efficiency throughout the study.Trailing edge populations showed a positive though non-significant trend in photosynthetic efficiency throughout winter MHWs exposure.Poleward and equatorward populations did not produce significantly different results,with winter MHWs having no negative affect on Fv/Fm of either population.Additionally,we found no long-term regional or population-level influence of a winter MHWs on this species’photosynthetic efficiency.Thus,we found no statistically significant difference in thermal stress responses between leading and trailing populations.Nonetheless,C.officinalis showed a trend towards higher stress responses in southern than northern populations.Because responses rest on a variety of local population traits,they are difficult to predict based solely on thermal pressures. 展开更多
关键词 marginal population coralline algae climate change ECOPHYSIOLOGY photophysiology MACROALGAE FV/FM
下载PDF
Central Upwind Scheme for Solving Multivariate Cell Population Balance Models
15
作者 Shahzadi Mubeen ur Rehman Nadia Kiran Shamsul Qamar 《Applied Mathematics》 2014年第8期1187-1201,共15页
Microbial cultures are comprised of heterogeneous cells that differ according to their size and intracellular concentrations of DNA, proteins and other constituents. Because of the included level of details, multi-var... Microbial cultures are comprised of heterogeneous cells that differ according to their size and intracellular concentrations of DNA, proteins and other constituents. Because of the included level of details, multi-variable cell population balance models (PBMs) offer the most general way to describe the complicated phenomena associated with cell growth, substrate consumption and product formation. For that reason, solving and understanding of such models are essential to predict and control cell growth in the processes of biotechnological interest. Such models typically consist of a partial integro-differential equation for describing cell growth and an ordinary integro-differential equation for representing substrate consumption. However, the involved mathematical complexities make their numerical solutions challenging for the given numerical scheme. In this article, the central upwind scheme is applied to solve the single-variate and bivariate cell population balance models considering equal and unequal partitioning of cellular materials. The validity of the developed algorithms is verified through several case studies. It was found that the suggested scheme is more reliable and effective. 展开更多
关键词 CELL population BALANCE CELL Growth Substrate CONSUMPTION CENTRAL UPWIND Scheme Equal and Unequal Partitioning of Cells
下载PDF
Potential Inbreeding in a Small Population of a Mass Flowering Species, <i>Xanthorrhoea johnsonii</i>(Xanthorrhoeaceae): Is Your Mother My Father?
16
作者 Rachel King Jacinta M. Zalucki 《American Journal of Plant Sciences》 2012年第3期303-312,共10页
Xanthorrhoea johnsonii is a long lived slow growing perennial understorey species, that produces a large quantity of passively dispersed seed every 3 - 5 years. Reproductive maturity is not reached until 20 - 30 years... Xanthorrhoea johnsonii is a long lived slow growing perennial understorey species, that produces a large quantity of passively dispersed seed every 3 - 5 years. Reproductive maturity is not reached until 20 - 30 years of age. The temporal asynchrony of the flowering event in this population was analogous to geographic isolation through fragmentation. A small population of plants flowering in isolation provided the opportunity to examine outcrossing rates, genetic diversity and the paternity of progeny at a small spatial scale (0.2 ha). The geographic location and physical characteristics of the adult plants were recorded, and both adults and their seed were sampled for genetic analysis. Four microsatellite loci were screened for genetic diversity and spatial structure analysis. A population outcrossing rate was estimated, as well as the number of paternal parents required to resolve the progeny multilocus genotypes. High genetic diversity was found in both adults and progeny with an estimated 97% outcrossing rate. All maternal lines required several paternal contributors, with no evidence of dominant paternal genotypes. Pollen transfer occurred between both geographically close and distant plants. 展开更多
关键词 Xanthorrhoeaceae INBREEDING Mass FLOWERING Microsatellite PATERNITY OUTCROSSING Pollen Dispersal Genetic Structure Isolated population Xanthorrhoea johnsonii
下载PDF
Estimating the Size of an Injecting Drug User Population
17
作者 Yang Zhao 《World Journal of AIDS》 2011年第3期88-93,共6页
This article describes a sampling and estimation scheme for estimating the size of an injecting drug user (IDU) population by combining classical sampling and respondent-driven sampling procedures. It is designed to u... This article describes a sampling and estimation scheme for estimating the size of an injecting drug user (IDU) population by combining classical sampling and respondent-driven sampling procedures. It is designed to use the information from harm reduction programs, especially, Needle Exchange Programs (NEPs). The approach involves using respondent-driven sampling design to collect a sample of injecting drug users who appear at site of NEP in a certain period of time and to obtain retrospective self-report data on the number of friends among the IDUs and number of needles exchanged for each sampled injecting drug user. A methodology is developed to estimate the size of injecting drug users who have ever used the NEP during the fixed period of time, and which allows us to estimate the proportion of injecting drug users in using NEP. The size of the IDU population is estimated by dividing the total number of IDUs who using NEPs during the period of time by the estimated proportion of IDUs in the group. The technique holds promise for providing data needed to answer questions such as “What is the size of an IDU population in a city?” and “Is that size changing?” and better understand the dynamics of the IDU population. The methodology described here can also be used to estimate size of other hard-to-reach population by using information from harm reduction programs. 展开更多
关键词 INJECTING Drug Users Needle Exchange Programs Respondent-Driven Sampling ESTIMATING the SIZE of AN IDU population
下载PDF
Economic Load Dispatch Based on Efficient Population Utilization Strategy for Particle Swarm Optimization
18
作者 Lei Wu Haiming Li +1 位作者 Zhengyang Wu Chenbin Wu 《International Journal of Communications, Network and System Sciences》 2015年第9期367-373,共7页
In this paper, the efficient population utilization strategy for particle swarm optimization (EPUSPSO) is proposed to solve the economic load dispatch (ELD) problem of power system. This algorithm improves the accurac... In this paper, the efficient population utilization strategy for particle swarm optimization (EPUSPSO) is proposed to solve the economic load dispatch (ELD) problem of power system. This algorithm improves the accuracy and the speed of its convergence by changing the number of particles effectively, and improving the velocity equation and position equation. In order to verify the effectiveness of the algorithm, this algorithm is tested in three different ELD cases of power system include IEEE 3-unit case, 13-unit case, and 40-unit case, and the obtained results are compared with those obtained from other algorithms using the same system parameters. The compared results show that the algorithm can find the optimal solution effectively and accurately, and avoid falling into the local optimal problem;meanwhile, faster speed can be ensured in the case. 展开更多
关键词 Economic Load DISPATCH EFFICIENT population UTILIZATION STRATEGY Particle SWARM Optimization Power System Valve Point Effect
下载PDF
Approximation of Finite Population Totals Using Lagrange Polynomial
19
作者 Lamin Kabareh Thomas Mageto Benjamin Muema 《Open Journal of Statistics》 2017年第4期689-701,共13页
Approximation of finite population totals in the presence of auxiliary information is considered. A polynomial based on Lagrange polynomial is proposed. Like the local polynomial regression, Horvitz Thompson and ratio... Approximation of finite population totals in the presence of auxiliary information is considered. A polynomial based on Lagrange polynomial is proposed. Like the local polynomial regression, Horvitz Thompson and ratio estimators, this approximation technique is based on annual population total in order to fit in the best approximating polynomial within a given period of time (years) in this study. This proposed technique has shown to be unbiased under a linear polynomial. The use of real data indicated that the polynomial is efficient and can approximate properly even when the data is unevenly spaced. 展开更多
关键词 LAGRANGE POLYNOMIAL APPROXIMATION Finite population Total AUXILIARY Information Local POLYNOMIAL Regression Horvitz Thompson and Ratio ESTIMATOR
下载PDF
Changes in the adult sex ratio of six duck species breeding populations over two decades
20
作者 Monika Homolkova Petr Musil +4 位作者 Diego Pavon-Jordan Dorota Gajdosova Zuzana Musilova Sarka Neuzilova Jan Zouhar 《Avian Research》 SCIE CSCD 2024年第2期202-210,共9页
Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of research... Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of researchers lacking convenient results for the active protection of endangered species.Species with male-bias populations are usually strongly affected by a decline in population size that leads to a higher extinction risk.In this study,we examined our long-term data of the abundance of breeding populations in six duck species(Mallard Anas platyrhynchos,Gadwall Mareca strepera,Red-crested Pochard Netta rufina,Common Pochard Aythya ferina,Tufted Duck Aythya fuligula,and Common Goldeneye Bucephala clangula)from fishponds in South Bohemia,Czechia,between 2004 and 2022.This evidence was used to assess long-term changes in the adult sex ratio in these breeding populations and investigate the possible effects of the NAO index(North Atlantic Oscillation index)on them,indicating climate conditions in winter.We determined a long-term decrease of the proportion of females in the breeding season in two of the six examined species:Common Pochard and Red-crested Pochard,which is driven by the long-term increase in the number of males in contrast to the decreasing or stable number of females likely caused by different migration behaviours between females and males.In the case of Common Pochard,in breeding populations,we estimated 60-65%of males in the early 2000s rising to 75-80%in the early 2020s.However,we establish no significant effects linked to climate conditions of the previous winter in these species as a crucial cause of the changes of the proportion of females in the breeding population. 展开更多
关键词 Adult sex ratio Breeding population population dynamics Red-listed species WATERFOWL Winter weather conditions
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部