期刊文献+
共找到56篇文章
< 1 2 3 >
每页显示 20 50 100
Knee Arthroplasty Incidence Rate vs. Revision of Knee Arthroplasty and Its Associated Comorbidities in Colombia
1
作者 Yolmira Johana Sanjuanelo Marenco Henry Oliveros Rodríguez Hector Posso 《Open Journal of Orthopedics》 2024年第5期247-257,共11页
Introduction: Total knee arthroplasty (TKA) has been established as a transformative solution in the treatment of advanced degenerative diseases of the knee, such as osteoarthritis, rheumatoid arthritis, and posttraum... Introduction: Total knee arthroplasty (TKA) has been established as a transformative solution in the treatment of advanced degenerative diseases of the knee, such as osteoarthritis, rheumatoid arthritis, and posttraumatic arthritis. In this sense, TKA surgery, which seeks to replace the damaged joint with prosthetic components, has proven to be highly effective in relieving pain, improving joint function, and, ultimately, significantly increasing patients’ quality of life. The present study describes the TKA and revision knee arthroplasty (RKA) rates and, identifies the associated co morbidities in the Colombian context. Methods: A retrospective cohort study was carried out. It describes demographic and clinical characteristics between two groups of patients, TKA or RKA, and its association with mortality at 30 days, 90 days, or one year after the intervention. Results: The incidence rate of the population undergoing TKA was approximately 11.71 cases per 100,000 inhabitants. Furthermore, the incidence rate for revision knee arthroplasty (RKA) procedures in the same period was around 0.96 per 100,000 inhabitants. In both groups at 30 days postoperatively, a total mortality rate of 0.09%was recorded. When the follow-up was extended to 90 days, it increased to 0.15%;at one year postoperatively, it rose to 0.88%. Conclusion: Mortality after surgery was low in Colombia in 2019. Although RKA is a beneficial procedure, in certain circumstances, it was noted that it carries a higher risk compared to primary TKA. Our results emphasize the importance of careful evaluation of co morbidities and risk factors in patients undergoing these surgical procedures. The application of quality-of-life questionnaires should be considered in future studies on effectiveness and mortality for TKA and RKA in our country. 展开更多
关键词 ARTHROPLASTY Co Morbidities Incidence rate PAIN MORTALITY
下载PDF
Deterministic and Stochastic Analysis of a New Rumor Propagation Model with Nonlinear Propagation Rate in Social Network
2
作者 Chunxin Liu 《Journal of Applied Mathematics and Physics》 2023年第11期3446-3463,共18页
This paper presents a study on a new rumor propagation model with nonlinear propagation rate and secondary propagation rate. We divide the total population into three groups, the ignorant, the spreader and the aware. ... This paper presents a study on a new rumor propagation model with nonlinear propagation rate and secondary propagation rate. We divide the total population into three groups, the ignorant, the spreader and the aware. The nonlinear incidence rate describes the psychological impact of certain serious rumors on social groups when the number of individuals spreading rumors becomes larger. The main contributions of this work are the development of a new rumor propagation model and some results of deterministic and stochastic analysis of the rumor propagation model. The results show the influence of nonlinear propagation rate and stochastic fluctuation on the dynamic behavior of the rumor propagation model by using Lyapunov function method and stochastic related knowledge. Numerical examples and simulation results are given to illustrate the results obtained. 展开更多
关键词 Rumor Model Nonlinear Incidence rate Secondary Propagation rate Stochastic Fluctuation
下载PDF
膀胱癌患者根治术后合并前列腺偶发癌的临床病理特征分析
3
作者 王阳 李新悟 +4 位作者 段启新 李征 胡跃世 谷傲峥 朱清 《实用癌症杂志》 2024年第5期831-833,844,共4页
目的分析膀胱癌患者根治术后合并前列腺偶发癌的临床病理特征。方法回顾性分析行膀胱癌根治术75例患者的临床资料,所有患者术前均未被诊断为前列腺癌,统计术后前列腺偶发癌的发生率。另收集患者的年龄、膀胱癌分期等资料,统计对比合并... 目的分析膀胱癌患者根治术后合并前列腺偶发癌的临床病理特征。方法回顾性分析行膀胱癌根治术75例患者的临床资料,所有患者术前均未被诊断为前列腺癌,统计术后前列腺偶发癌的发生率。另收集患者的年龄、膀胱癌分期等资料,统计对比合并前列腺偶发癌与未合并前列腺偶发癌患者各项临床资料的差异;同时统计分析合并前列腺偶发癌患者的病理特点;于术后进行随访,统计所有患者的生存率。结果75例患者中,合并前列腺偶发癌的共有18例,发生率为24.00%(18/75);合并前列腺偶发癌的患者年龄高于未合并前列腺偶发癌患者,有统计学差异(P<0.05);而两组术前的国际前列腺症状评分(IPSS)、生活质量综合评定问卷(GQOLI-74)、前列腺特异抗原(PSA)相比,无统计学差异(P>0.05);18例合并前列腺偶发癌的患者其临床分期大部分局限于pT_(2)内,其中pT_(1)有10例(55.56%),pT_(2)有5例(27.78%),pT 3有3例(16.67%);采用Gleason score评分对患者评估,其中<7分11例(61.11%)、=7分5例(27.78%)、>7分2例(11.11%);术后随访成功60例,生存率为80.00%(60/75),其中11例死于膀胱癌,4例死于其他疾病。结论膀胱癌根治术后前列腺偶发癌的发生率较高,大多局限于pT_(2)内,且Gleason score评分多数≤7分,前列腺偶发癌的发生对膀胱癌患者总体生存率无显著影响。 展开更多
关键词 膀胱癌 前列腺偶发癌 临床病理特征 生存率
下载PDF
通过泛读伴随性词汇学习的影响因素及基本原则
4
作者 翟颖华 刘柳盈 《湖北成人教育学院学报》 2024年第2期103-108,共6页
通过泛读伴随性词汇学习是词汇学习的重要组成部分,是一种行之有效的自主学习方式,但也存在局限性。通过大量阅读获得的词汇能力主要是接受性的,并且不以效率见长。本文探讨了生词密度、生词复现率和生词输入调整三个因素对通过泛读获... 通过泛读伴随性词汇学习是词汇学习的重要组成部分,是一种行之有效的自主学习方式,但也存在局限性。通过大量阅读获得的词汇能力主要是接受性的,并且不以效率见长。本文探讨了生词密度、生词复现率和生词输入调整三个因素对通过泛读获得词汇知识的影响。最后提出,严格控制阅读文本的难度、足够的输入量、让学习者自主选择阅读的内容、适当引入刻意词汇学习是通过泛读伴随性词汇学习应该遵守的基本原则。 展开更多
关键词 伴随性词汇学习 影响因素 基本原则 生词密度 生词复现率
下载PDF
Stability of a Delayed Stochastic Epidemic COVID-19 Model with Vaccination and with Differential Susceptibility
5
作者 Modeste N’zi Boubacar Sidiki Kouyaté +1 位作者 Ilimidi Yattara Modibo Diarra 《Journal of Applied Mathematics and Physics》 2024年第2期509-532,共24页
In this paper, we treat the spread of COVID-19 using a delayed stochastic SVIRS (Susceptible, Infected, Recovered, Susceptible) epidemic model with a general incidence rate and differential susceptibility. We start wi... In this paper, we treat the spread of COVID-19 using a delayed stochastic SVIRS (Susceptible, Infected, Recovered, Susceptible) epidemic model with a general incidence rate and differential susceptibility. We start with a deterministic model, then add random perturbations on the contact rate using white noise to obtain a stochastic model. We first show that the delayed stochastic differential equation that describes the model has a unique global positive solution for any positive initial value. Under the condition R<sub>0</sub> ≤ 1, we prove the almost sure asymptotic stability of the disease-free equilibrium of the model. 展开更多
关键词 SIRS Delayed Epidemic Model Nonlinear Incidence rate Lyapunov Function Asymptotic Stability in Probability
下载PDF
GLOBAL STABILITY OF SIRS EPIDEMIC MODELS WITH A CLASS OF NONLINEAR INCIDENCE RATES AND DISTRIBUTED DELAYS 被引量:6
6
作者 Yoichi Enatsu Yukihiko Nakata Yoshiaki Muroya 《Acta Mathematica Scientia》 SCIE CSCD 2012年第3期851-865,共15页
In this article, we establish the global asymptotic stability of a disease-free equilibrium and an endemic equilibrium of an SIRS epidemic model with a class of nonlin- ear incidence rates and distributed delays. By u... In this article, we establish the global asymptotic stability of a disease-free equilibrium and an endemic equilibrium of an SIRS epidemic model with a class of nonlin- ear incidence rates and distributed delays. By using strict monotonicity of the incidence function and constructing a Lyapunov functional, we obtain sufficient conditions under which the endemic equilibrium is globally asymptotically stable. When the nonlinear inci- dence rate is a saturated incidence rate, our result provides a new global stability condition for a small rate of immunity loss. 展开更多
关键词 SIRS epidemic model nonlinear incidence rate global asymptotic stability distributed delays Lyapunov functional
下载PDF
TWO DIFFERENTIAL INFECTIVITY EPIDEMIC MODELS WITH NONLINEAR INCIDENCE RATE 被引量:1
7
作者 Chen Junjie 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第3期305-315,共11页
This paper considers two differential infectivity(DI) epidemic models with a nonlinear incidence rate and constant or varying population size. The models exhibits two equilibria, namely., a disease-free equilibrium ... This paper considers two differential infectivity(DI) epidemic models with a nonlinear incidence rate and constant or varying population size. The models exhibits two equilibria, namely., a disease-free equilibrium O and a unique endemic equilibrium. If the basic reproductive number σ is below unity,O is globally stable and the disease always dies out. If σ〉1, O is unstable and the sufficient conditions for global stability of endemic equilibrium are derived. Moreover,when σ〈 1 ,the local or global asymptotical stability of endemic equilibrium for DI model with constant population size in n-dimensional or two-dimensional space is obtained. 展开更多
关键词 differential infectivity nonlinear incidence rate endemic equilibrium global stability Liapunov function.
下载PDF
Stability Analysis of SIQS Epidemic Model with Saturated Incidence Rate 被引量:1
8
作者 O. Adebimpe L. M. Erinle-Ibrahim A. F. Adebisi 《Applied Mathematics》 2016年第10期1082-1086,共5页
A SIQS epidemic model with saturated incidence rate is studied. Two equilibrium points exist for the system, disease-free and endemic equilibrium. The stability of the disease-free equilibrium and endemic equilibrium ... A SIQS epidemic model with saturated incidence rate is studied. Two equilibrium points exist for the system, disease-free and endemic equilibrium. The stability of the disease-free equilibrium and endemic equilibrium exists when the basic reproduction number R0, is less or greater than unity respectively. The global stability of the disease-free and endemic equilibrium is proved using Lyapunov functions and Poincare-Bendixson theorem plus Dulac’s criterion respectively. 展开更多
关键词 SIQS Epidemic Model Saturated Incidence rate Basic Reproduction Number Lyapunov Function Poincare-Bendixson Dulac Criterion
下载PDF
Dynamics of a Nonautonomous SIR Model with Time-Varying Impulsive Release and General Nonlinear Incidence Rate in a Polluted Environment 被引量:1
9
作者 Fumin Zhang Shujing Gao +1 位作者 Yujiang Liu Yan Zhang 《Applied Mathematics》 2016年第7期681-693,共13页
In a polluted environment, considering the biological population infected with a kind of disease and hunted by human beings, we formulate a nonautonomous SIR population-epidemic model with time-varying impulsive relea... In a polluted environment, considering the biological population infected with a kind of disease and hunted by human beings, we formulate a nonautonomous SIR population-epidemic model with time-varying impulsive release and general nonlinear incidence rate and investigate dynamical behaviors of the model. Under the reasonable assumptions, the sufficient conditions which guarantee the globally attractive of the disease-free periodic solution and the permanence of the infected fish are established, that is, the infected fish dies out if , whereas the disease persists if . To substantiate our theoretical results, extensive numerical simulations are performed for a hypothetical set of parameter values. 展开更多
关键词 Nonautonomous SIR Model Varying Pulses General Nonlinear Incidence rate Global Attractivity
下载PDF
Predicting COVID-19 fatality rate based on age group using LSTM
10
作者 Zahra Ramezani Seyed Abbas Mousavi +3 位作者 Ghasem Oveis Mohammad Reza Parsai Fatemeh Abdollahi Jamshid Yazdani Charati 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2021年第12期564-574,共11页
Objective: To predict the daily incidence and fatality rates based on long short-term memory(LSTM) in 4 age groups of COVID-19 patients in Mazandaran Province, Iran.Methods: To predict the daily incidence and fatality... Objective: To predict the daily incidence and fatality rates based on long short-term memory(LSTM) in 4 age groups of COVID-19 patients in Mazandaran Province, Iran.Methods: To predict the daily incidence and fatality rates by age groups, this epidemiological study was conducted based on the LSTM model. All data of COVID-19 disease were collected daily for training the LSTM model from February 22, 2020 to April 10, 2021 in the Mazandaran University of Medical Sciences. We defined 4 age groups, i.e., patients under 29, between 30 and 49, between 50 and 59, and over 60 years old. Then, LSTM models were applied to predict the trend of daily incidence and fatality rates from 14 to 40 days in different age groups. The results of different methods were compared with each other.Results: This study evaluated 5 0826 patients and 5 109 deaths with COVID-19 daily in 20 cities of Mazandaran Province. Among the patients, 25 240 were females(49.7%), and 25 586 were males(50.3%). The predicted daily incidence rates on April 11, 2021 were 91.76, 155.84, 150.03, and 325.99 per 100 000 people, respectively;for the fourteenth day April 24, 2021, the predicted daily incidence rates were 35.91, 92.90, 83.74, and 225.68 in each group per 100 000 people. Furthermore, the predicted average daily incidence rates in 40 days for the 4 age groups were 34.25, 95.68, 76.43, and 210.80 per 100 000 people, and the daily fatality rates were 8.38, 4.18, 3.40, 22.53 per 100 000 people according to the established LSTM model. The findings demonstrated the daily incidence and fatality rates of 417.16 and 38.49 per 100 000 people for all age groups over the next 40 days. Conclusions: The results highlighted the proper performance of the LSTM model for predicting the daily incidence and fatality rates. It can clarify the path of spread or decline of the COVID-19 outbreak and the priority of vaccination in age groups. 展开更多
关键词 COVID-19 Long short-term memory model Incidence rate Fatality rate PREDICTION Age classification
下载PDF
Implication of Reported Viral Hepatitis Incidence Rate Change in Hubei Province, China, between 2004-2010
11
作者 胡樱 宇传华 +1 位作者 陈邦华 王雷 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2012年第3期428-433,共6页
This study examined the change of reported incidence rate for viral hepatitis in Hubei province, China, between 2004 to 2010 to provide scientific evidence for viral hepatitis control. Reported viral hepatitis infecti... This study examined the change of reported incidence rate for viral hepatitis in Hubei province, China, between 2004 to 2010 to provide scientific evidence for viral hepatitis control. Reported viral hepatitis infection cases were queried from Centre for Disease Control of Hubei Province, China. The incidence of viral hepatitis A decreased steadily across the study period. Viral hepatitis B composed 85% of the viral hepatitis cases. When reported incidence rates for chronic hepatitis B increased, the rates of acute and unclassified cases dropped from 2005 to 2010. The reported viral hepatitis B incidence rate for males was around 1.5-2 times higher than for females. The average annual percentage change of reported viral hepatitis B incidence rates was 4%. The same index for viral hepatitis C was 28%. The reported viral hepatitis B incidence rate of people under 20 years old declined over the period. This decrease was mainly attributed to the recent implementation of vaccination plan. Reported incidence rate of viral hepatitis E also rose in those years. Having a better understanding on reported incidence rates of the present surveillance system is important for developing strategies for further prevention of viral hepatitis. In addition, the data showed that a surveillance system that differentiates new and former infected cases will be more effective in providing evidence for disease control. 展开更多
关键词 viral hepatitis reported incidence rate VACCINATION PREVENTION
下载PDF
Trends of incidence and mortality rates of stroke from 1983 to 2000 in Hanzhong rural population
12
作者 龙泳 高保林 +5 位作者 张景霞 杨军 黄久仪 胡继新 徐德忠 卢娟 《Journal of Medical Colleges of PLA(China)》 CAS 2003年第5期331-334,共4页
Objective: To explore the trends of incidence and mortality rates of stroke in Hanzhong rural population. Methods: Acting as the WHO MONICA project. Results: The incidence rate of stroke was 152.9/100 000. There was d... Objective: To explore the trends of incidence and mortality rates of stroke in Hanzhong rural population. Methods: Acting as the WHO MONICA project. Results: The incidence rate of stroke was 152.9/100 000. There was decline trend in male(P<0.05). The mortality rate of stroke was 115.9/100 000. There was no significant decline trend during 18-year period (P<0.05). The incidence and mortality rates of stroke of male were higher than those of female(P<0.05).The incidence and mortality rates were all increased with age(P<0.01). Conclusion: It must stick to the long- term prevention measures to decrease incidence rate, and improve the condition of medical treatment to reduce the mortality rate in rural population. 展开更多
关键词 STROKE incidence rate mortality rate
下载PDF
Global Analysis of an SEIR Epidemic Model with Nonlinear Incidence Rates
13
作者 贾滢 刘俊利 《Chinese Quarterly Journal of Mathematics》 2016年第3期237-247,共11页
In this paper,an SEIR model with nonlinear incidence rates are studied.The basic reproduction number R_0 characterizes the disease transmission dynamics: if R_0≤ 1,the disease-free equilibrium is globally asymptotica... In this paper,an SEIR model with nonlinear incidence rates are studied.The basic reproduction number R_0 characterizes the disease transmission dynamics: if R_0≤ 1,the disease-free equilibrium is globally asymptotically stable and the disease always dies out,if R_0> 1 then there is a unique endemic equilibrium which is globally asymptotically stable and the disease persists. 展开更多
关键词 SEIR model nonlinear incidence rate compound matrices global stability
下载PDF
National Breast Cancer Mortality and Incidence Rates According to the Human Development Index: An Ecological Study
14
作者 Salman Khazaei Shahab Rezaeian +4 位作者 Zaher Khazaei Leila Molaeipoor Shahrzad Nematollahi Parvaneh Lak Somayeh Khazaei 《Advances in Breast Cancer Research》 2016年第1期30-36,共7页
Background: This study aimed to identify the role of human development index (HDI) in the incidence and mortality rates of breast cancer (BC) worldwide. Methods: Data on the age-standardized incidence and mortality ra... Background: This study aimed to identify the role of human development index (HDI) in the incidence and mortality rates of breast cancer (BC) worldwide. Methods: Data on the age-standardized incidence and mortality rates of BC for 184 countries were obtained from the GLOBOCAN. Data about the HDI and other indices were obtained from the World Bank Report 2013. Linear regression model was used for assessment the effect of HDI on BC occurrence rates. Results: In 2012, BCs were estimated to have affected a total of 1,671,149 individuals (crude rate: 47.8 per 100,000 individuals), and caused 521,907 deaths worldwide (crude rate: 14.7 per 100,000 individuals). Nearly half of total female BC cases (46.3%) with the highest risk of incidence (age-standardized Rate (ASR): 128 per 100,000) had occurred in very high HDI regions. The most proportion of the mortality burden was in low HDI and medium HDI areas. Linear regression analyses showed a direct significant correlation between the incidence of BC and HDI at the global level (B = 104.5, P < 0.001). The mortality rate of BC was not significantly associated with HDI (B = 3.26, P = 0.160). Conclusion: Our study showed that the burden of female BC is enormous in very high HDI and low HID regions. Targeted interventions have the ability to reduce this number significantly through resource-dependent interventions. Moreover, further reductions in mortality could be brought about by increasing access to curative treatment for patients with BC. 展开更多
关键词 Breast Cancer Human Development Index INCIDENCE Age-Standardized Incidence and Mortality rates
下载PDF
H1-antihistamine use and head and neck cancer risk in type 2 diabetes mellitus
15
作者 YI-NONG CHEN YING-LIN CHEN +4 位作者 WAN-MING CHEN MINGCHIH CHEN BEN-CHANG SHIA JENQ-YUH KO SZU-YUAN WU 《Oncology Research》 SCIE 2023年第1期23-34,共12页
This study aimed to examine the association between the use of H1-antihistamines(AHs)and head and neck cancer(HNC)risk in patients with type 2 diabetes mellitus(T2DM).Data from the National Health Insurance Research D... This study aimed to examine the association between the use of H1-antihistamines(AHs)and head and neck cancer(HNC)risk in patients with type 2 diabetes mellitus(T2DM).Data from the National Health Insurance Research Database of Taiwan were analyzed for the period from 2008 to 2018.A propensity-score-matched cohort of 54,384 patients each in the AH user and nonuser groups was created and analyzed using Kaplan-Meier method and Cox proportional hazards regression.The results showed that the risk of HNC was significantly lower in AH users(adjusted hazard ratio:0.55,95%CI:0.48 to 0.64)and the incidence rate was also lower(5.16 vs.8.10 per 100,000 person-years).The lower HNC incidence rate in AH users(95%CI:0.63;0.55 to 0.73)suggests that AH use may reduce the risk of HNC in T2DM patients. 展开更多
关键词 Type 2 diabetes H1-Antihistamine Head and neck cancer INCIDENCE Incidence rate
下载PDF
Evaluation and application of a milk antibody ELISA for assessing the prevalence and incidence of bovine tuberculosis in dairy herds in Hubei Province,China
16
作者 Yingyu Chen Shuang Cheng +4 位作者 Yu Wang Guiqiang Wang Xijuan Wu Ian D.Robertson Aizhen Guo 《Animal Diseases》 2023年第2期143-151,共9页
Bovine tuberculosis(bTB)is a chronic zoonotic disease that is endemic in China.Current in-vitro tests for bTB are mainly based on blood assays.Collection of samples results in some stress to the sampled cattle and ass... Bovine tuberculosis(bTB)is a chronic zoonotic disease that is endemic in China.Current in-vitro tests for bTB are mainly based on blood assays.Collection of samples results in some stress to the sampled cattle and associated economic losses for the herd owner.This study was designed to investigate the relationship between milk and serum antibody tests for bTB in dairy cows using 85 cows with milk and corresponding blood samples.Totally 4,395 milk samples were used to assesse the apparent(test)prevalence and incidence of bTB using the milk antibody ELISA.The association between levels of bTB milk antibody and milk quality was also evaluated.Milk and serum antibody tests showed a good correlation with a 87.5%(95%CI:61.7%,98.4)positive agreement and 98.7%(95%CI:95.4,99.8)negative agreement.The animal level lactoprevalence ranged from 0.3%(95%CI:0,1.2)to 33.3%(95%CI:26.6,40.6)in different farms and the incidence rate ranged from 0 head/cow-month(95%CI:0,0.02)to 0.04 head/cow-month(95%CI:0.02,0.07).Twenty percent of sampled farms met the criteria for bTB control in China.The prevalence on large-scale farms was lower(p<0.001)than on small farms.The bTB milk antibody levels had a negative correlation with milk yield and a positive correlation with somatic cell count(SCC),milk protein percentage(MPP)and percentage of total solids(TS).According to this research,milk ELISA could be used as a supplement of blood samples to assist in the surveillance for bTB and for alerting control and eradication of bTB. 展开更多
关键词 Bovine Tuberculosis Milk antibody PREVALENCE Incidence rate Milk quality
下载PDF
Evolution of Acquired Humoral Immunity after Full Vaccination against SARS-CoV-2. IgG Levels in Healthcare Workers at 6 and 9 Months
17
作者 Victoria Delicado-Useros Esther Navarro-Rodenas +7 位作者 Indalecio-M Sánchez-Onrubia Carmen Ortega-Martínez Antonia Alfaro-Espín Juan-D Pérez-Serra Francisco García-Alcaraz Julia Lozano-Serra Lorena Robles-Fonseca Teresa Pérez-Domenech 《World Journal of Vaccines》 CAS 2023年第2期13-32,共20页
Background: The COVID-19 pandemic continues to be a major worldwide health problem. The present study aims to contribute to surveillance of the immune and clinical response of vaccines to SARS-CoV-2. Methods: Observat... Background: The COVID-19 pandemic continues to be a major worldwide health problem. The present study aims to contribute to surveillance of the immune and clinical response of vaccines to SARS-CoV-2. Methods: Observational medication study on acquired immunity and effectiveness of vaccines. Population: 620 workers in the health service of Almansa (Spain). Representative sample of 150 individuals. Sociodemographic, clinical, and epidemiological data and samples were recorded to determine anti-SARS-CoV-2 serum IgG levels 6 and 9 months after vaccination with Pfizer. Results: Mean age 46.45 years;76% women;85.1% working in a hospital. 19.3% had had COVID-19 in the year prior to vaccination. 96.7% were fully vaccinated with Pfizer/BioNTech. At 6 months, 100% seropositivity and mean IgG levels of 3017.2 AU/ml. Significant variations in IgG levels in individuals with prior COVID-19 infection and smokers. At 9 months, 99.3% remained seropositive;2.8% infected after vaccination. The repeated measures analysis showed a difference in means of 669.0 AU/ml (significant decrease in IgG levels of 28.9%). Conclusion: Antibody levels remained positive 6 and 9 months after vaccination, although IgG levels were found to decay. 展开更多
关键词 Acquired Immunity SARS-CoV-2 Vaccine IgG level Healthcare Workers COVID-19 Incidence rate
下载PDF
Global Dynamics Analysis of a Cholera Transmission Model with General Incidence and Multiple Modes of Infection
18
作者 Daijun Li Lianwen Wang 《Journal of Applied Mathematics and Physics》 2023年第11期3747-3759,共13页
This paper develops an SIBR cholera transmission model with general incidence rate. Necessary and sufficient conditions for local and global asymptotic stability of the equilibria are established by Routh Hurwitz crit... This paper develops an SIBR cholera transmission model with general incidence rate. Necessary and sufficient conditions for local and global asymptotic stability of the equilibria are established by Routh Hurwitz criterium, Lyapunov function, and the second additive composite matrix theorem. What is more, exploiting the DED is cover simulation tool, the parameter values of the model are estimated with the 1998-2021 cholera case data in China. Finally, we perform sensitivity analysis for the basic reproduction number to seek for effective interventions for cholera control. . 展开更多
关键词 Cholera Transmission Model Nonlinear Incidence rate Second Additive Composite Matrix Lyapunov Function Global Stability
下载PDF
A Novel Analysis Approach of Uniform Persistence for an Epidemic Model with Quarantine and Standard Incidence Rate
19
作者 Song-bai GUO Yu-ling XUE +1 位作者 Xi-liang LI Zuo-huan ZHENG 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2024年第3期695-707,共13页
Inspired by the transmission characteristics of the coronavirus disease 2019(COVID-19),an epidemic model with quarantine and standard incidence rate is first developed,then a novel analysis approach is proposed for fi... Inspired by the transmission characteristics of the coronavirus disease 2019(COVID-19),an epidemic model with quarantine and standard incidence rate is first developed,then a novel analysis approach is proposed for finding the ultimate lower bound of the number of infected individuals,which means that the epidemic is uniformly persistent if the control reproduction number R_(c)>1.This approach can be applied to the related biomat hem at ical models,and some existing works can be improved by using that.In addition,the infection-free equilibrium V^(0)of the model is locally asymptotically stable(LAS)if R_(c)<1 and linearly stable if R_(c)=1;while V^(0)is unstable if R_(c)>1. 展开更多
关键词 uniform persistence epidemic model control reproduction number QUARANTINE standard incidence rate
原文传递
The effect of the fear factor on the dynamics of an eco-epidemiological system with standard incidence rate
20
作者 Chunmei Zhang 《Infectious Disease Modelling》 CSCD 2024年第1期128-141,共14页
In order to protect endangered prey,ecologists suggest introducing parasites into predators which have achieved the expected goal in practice.Then how to explain the inherent mechanism and validate the effectiveness o... In order to protect endangered prey,ecologists suggest introducing parasites into predators which have achieved the expected goal in practice.Then how to explain the inherent mechanism and validate the effectiveness of this approach theoretically?In response to this question,we propose an eco-epidemiological system with the standard incidence rate and the anti-predator behavior in this paper,where the predator population is infected by parasites.We show the existence and local stability of equilibria for the system,and verify the occurrence of Hopf bifurcation.Theoretical and numerical results suggest that the fear effect reduces the density of the predator population but has no effect on the density of prey population.In addition,the cost of fear may not only break the stability of the equilibrium of the system,but also induce the equilibrium to change from unstable to stable.Based on the theoretical analysis,we confirm that introducing parasites into the predator population is an effective method to protect endangered prey. 展开更多
关键词 Eco-epidemiological system Fear factors Standard incidence rate Stability Bifurcation.2010 MSC 92A17
原文传递
上一页 1 2 3 下一页 到第
使用帮助 返回顶部