A study of precancerous gastric lesion was conducted in a randomly selected high risk population in Linqu, Shandong Province of China. 849 subjects aged from 30-64 were examined bioptically. There were 8 cases of gast...A study of precancerous gastric lesion was conducted in a randomly selected high risk population in Linqu, Shandong Province of China. 849 subjects aged from 30-64 were examined bioptically. There were 8 cases of gastric cancer, the prevalence rate was 0.9%. 169 subjects were diagnosed to be dysplasia, the prevalence rate of dysplasia was increased significantly with age. The regression equation was Y=0.47X-0.25. The prevalence of CAG was found in 36 per cent of the studied subjects and both dysplasia and CAG were more serious in the antrum than the. fundus. The results showed a natural history of precancerous gastric lesions in a high risk population in a high risk area.展开更多
A series of indicators, including serum lysozyme activity, G-banding chromosome aberration (G-banding CA) analysis, sister chromatid exchanges (SCEs), chromosome aberration (CA), T-lymphocyte transformation rate (TcTR...A series of indicators, including serum lysozyme activity, G-banding chromosome aberration (G-banding CA) analysis, sister chromatid exchanges (SCEs), chromosome aberration (CA), T-lymphocyte transformation rate (TcTR),-GT, GPT and AKP, were employed in the present survey among occupationally vinyl chloride (VC) exposed workers and inhabitants living in VC polluted area in a polyvinyl chloride (PVC) factory. The results showed that the serum lysozyme (S-LZM) activities in Group 3 (adult inhabitants exposed to 0.20 mg/m3 VC for at least 8 years), Group 2 (workers exposed to 4.1 mg/m3for at least 7 years occupationally), Group 1 (workers exposed to 25.7 mg/m3 for at least 2 years) were significantly higher than control. G-banding CA analysis showed that the total chromosome breakage rates in both Groups 1 and 2 were higher, but no difference existed between Group 3 and control. Only Group 1 was observed having higher SCEs, CA level and lower TcTR than control. AKP levels in Groups 1 and 2 were higher than control,but noγ-GT and GPT differences were found among groups. The study also suggests that G-banding CA analysis is more sensitive than CA and SCEs展开更多
AIM: To determine the main visual symptoms in a Brazilian population sample, associated to refractive errors(REs) and spectacle need to suggest priorities in preventive programs.METHODS: A cross-sectional study wa...AIM: To determine the main visual symptoms in a Brazilian population sample, associated to refractive errors(REs) and spectacle need to suggest priorities in preventive programs.METHODS: A cross-sectional study was conducted in nine counties of the southeast region of Brazil, using a systematic sampling of households, between March 2004 and July 2005. The population was defined as individuals aged between 1 and 96 y, inhabitants of 3600 residences to be evaluated and 3012 households were included,corresponding to 8010 subjects considered for participation in the survey, of whom 7654 underwent ophthalmic examinations. The individuals were evaluated according their demographic data, eye complaints and eye examination including the RE and the need to prescribe spectacles according to age. Statistical analysis was performed using SPSS software package and descriptive analysis using 95% confidence intervals(P〈0.05). RESULTS: The main symptom detected was asthenopia, most frequent in the 2ndand 3rddecades of life, with a significant decline after the 4thdecade.Astigmatism was the RE most associated with asthenopia. Reduced near vision sight was more frequent in those ≥40y with a progressive decline thereafter.Spectacles were most frequently required in subjects of≥40 years of age.CONCLUSION: The main symptom related to the vision was asthenopia and was associated to astigmatism. The greatest need for spectacles prescription occurred after40's, mainly to correct near vision. Subjects of ≥40years old were determined to be at high risk of uncorrected REs. These observations can guide intervention programs for the Brazilian population.展开更多
In this study, we analyze how vitamin D (VD) serum levels flow with latitude and throughout seasons of the year within a population sample over three years, taking into account that VD is mainly photosynthesized in th...In this study, we analyze how vitamin D (VD) serum levels flow with latitude and throughout seasons of the year within a population sample over three years, taking into account that VD is mainly photosynthesized in the skin from sun exposure. Vitamin D levels have been measured in 80,763 patients during 2013, 2014, and 2015. To accomplish the objectives, we first perform some inference tests like two-way Analysis of Variance (ANOVA) followed by post-hoc tests. Secondly, we develop time series techniques including cross correlation calculations. Least than 10% of the sample had healthy VD levels, which should be a fact of public health major concern. The effect of the interaction between the two factors, zones and seasons, was proved by ANOVA. The mean values which are significantly different were determined by post hoc test. Furthermore, we find that mean serum VD levels, measured as 25-hydroxy-VD, follow a seasonal lag pattern of 9 weeks, a delay for minimum and maximum values after the respective equinoxes and daily sunlight duration. Reliable estimates of the population are provided in the present study, since one of the strengths is its huge sample size. We have quantitatively characterized the seasonality of serum vitamin D levels in the Argentine and the seasonal lag pattern has been determined for the study region.展开更多
The aim of this population study was to identify personality traits among older (>65 years) male and female owners of cats and dogs and to compare their general health status in relation to their personality. Furth...The aim of this population study was to identify personality traits among older (>65 years) male and female owners of cats and dogs and to compare their general health status in relation to their personality. Further, the aim was to examine whether current cat and dog ownership could be predicted by the owners’ personality and health. Data were collected from the North-Trøndelag Health Study (HUNT) in Norway. Included were a total of 1897 cat or dog owners between the ages of 65 years and 101 years. The results showed that there were a higher proportion of introverted male cat owners than extraverted ones. Moreover, a majority of women with cats reported that their health was not good. Furthermore, female cat owners who displayed higher scores on neurotic traits experienced significantly poorer health compared to those female cat owners that experienced good health. The same was true for female cat owners who considered themselves to be introverted. Neither personality nor health could predict pet-ownership, but it was more likely for older individuals (80-101 years) to own a cat than a dog. This study has shown that human personality is associated with cat and dog ownership, but there are other factors connected with pet ownership as well.展开更多
It is evident that both recruitment and retention play critical roles in clinical trials. Recruitment and retention models are beginning to be analyzed worldwide in an effort to assess how to conduct studies more effi...It is evident that both recruitment and retention play critical roles in clinical trials. Recruitment and retention models are beginning to be analyzed worldwide in an effort to assess how to conduct studies more efficiently, all the while, allowing researchers to provide sound and ethical data to help advance medicine through clinical studies. Sponsors and sites have recognized that clinical trial enrollment must become more diverse and inclusive. In this review, we address the important topics of recruitment and retention in clinical trials. Specifically, the obstacles in regard to recruiting vulnerable populations. Methodologies to improve both the understanding of the study population and community engagement are outlined. In particular, newer strategies such as use of social media and more reliable strategies such as trust and relationship building are described in detail. A strong focus on recruitment is becoming widely recognized as being of such importance that consideration is given to this key component even during initial protocol development. Attention to recruitment and retention in the strategic planning process of clinical trials can mitigate enrollment issues that clinical researchers are experiencing.展开更多
Stimulated-Raman-adiabatic-passage (STIRAP) process provides an effective technique to transfer electron population from an initial state (e.g. ground state) to excited final state for both atoms and molecules. In thi...Stimulated-Raman-adiabatic-passage (STIRAP) process provides an effective technique to transfer electron population from an initial state (e.g. ground state) to excited final state for both atoms and molecules. In this paper, we present the results of the study on electron population transfer in three level system. We have analyzed the effects of various conditions on the transfer process, such as the time delay of the two laser beams, two-photon off-resonance, one-photon off-resonance and the change of relative laser intensity. The numerical result is compared with experiment, and the reasons for the effects are also given.展开更多
A population inversion study of GaAs/AlxGa1-xAs three-quantum-well quantum cascade structures is presented. We derive the population inversion condition (PIC) of the active region (AR) and discuss the PICs on diff...A population inversion study of GaAs/AlxGa1-xAs three-quantum-well quantum cascade structures is presented. We derive the population inversion condition (PIC) of the active region (AR) and discuss the PICs on different structures by changing structural parameters such as the widths of quantum wells or barriers in the AR. For some instances, the PIC can be simplified and is proportional to the spontaneous emission lifetime between the second and the first excited states, whereas some other instances imply that the PIC is proportional to the state lifetime of the second excited state.展开更多
Objective To study the population pharmacokinetic(PPK)profiles of linezolid in Chinese healthy volunteers and infected patients.Methods Linezolid 600 mg was administered to 31 Chinese healthy volunteers with a single ...Objective To study the population pharmacokinetic(PPK)profiles of linezolid in Chinese healthy volunteers and infected patients.Methods Linezolid 600 mg was administered to 31 Chinese healthy volunteers with a single dose and to 57 infected patients every 12 h for at least5 doses.High performance liquid chromatography was applied to determine the plasma concentration of linezol-展开更多
The last 4 decades of reform and opening up have not only witnessed the rapid development of China’s social economy,but have also marked the crucial transition of China’s demographic structure from one that is matur...The last 4 decades of reform and opening up have not only witnessed the rapid development of China’s social economy,but have also marked the crucial transition of China’s demographic structure from one that is mature to one that is old.As China’s population has aged rapidly in recent years,studies of aging have made worthwhile achievements documenting the process.This article mainly summarizes the development of studies on aging in China during the past 40 years and finds that research into the topic of aging during these years can be divided into three phases.The phases are characterized by particular kinds of research.Phase one,the study of aging trends and causes;phase two,the study of aging characteristics and policy responses;and phase three,the study of top-level design of aging policies and programs,and the development of integrated interdisciplinary research efforts.The five main characteristics of China’s studies on aging during the past 4 decades and five future prospects for studies on aging are discussed at the end of this paper.展开更多
Background and Aims:Recently,the World Health Organization adopted the first-ever global hepatitis strategy with the dream of eliminating viral hepatitis as a public health threat by 2030.However,the epidemiology and ...Background and Aims:Recently,the World Health Organization adopted the first-ever global hepatitis strategy with the dream of eliminating viral hepatitis as a public health threat by 2030.However,the epidemiology and treatment rates of hepatitis C virus(HCV)infection in Western China are still unknown.Methods:A total of 111,916 adult individuals(15-96 years)who underwent the HCV-antibody(HCV-Ab)test in the Second Affiliated Hospital of Chongqing Medical University between 2013 and 2015 were included in this study.We retrospectively analyzed the electronic medical records'data for each,and the positivity of HCV-Ab and the treatment of HCV RNA-positive patients were evaluated.Results:During 2013-2015,the crude prevalence of HCVAb was 1.4%(95%CI:1.4-1.5;1,611/111,916)and the adjusted prevalence of HCV-Ab was 1.7%(95%CI:1.6-1.8),which was higher than in the 2006 national study(0.43%).The prevalence was 2-times higher in males than females(2.0%vs.1.1%,p<0.01).Notably,only 46%(434/951)of the HCV RNA-positive patients received standard peginterferon plus ribavirin treatment,with 370(82%)that completed treatment,of whom 272(74%)achieved sustained virologic response(SVR).Particularly,11%(32/292)of HCV RNA-positive patients were HBsAg-positive,and the SVR rate for them was lower than for the HBsAg-negative patients,but no significant difference was observed.Conclusions:HCV infection may have increased since 2006 in Western China.The SVR rate of peg-interferon plus ribavirin treatment was high,but the proportion of untreated HCV patients was large.Thus,more efforts need to be made by the government to create a scientific-based policy for HCV treatment and prevention.展开更多
This paper reviews the progress of population geography in China since the 1980 s. The review results suggest that contrary to the common perception of its invisibility and marginalized status in the field, tremendous...This paper reviews the progress of population geography in China since the 1980 s. The review results suggest that contrary to the common perception of its invisibility and marginalized status in the field, tremendous progress has been made in population geography in China since the 1980 s. Population geographers have made significant contribution to the understanding of a wide range of population issues from geographical perspectives, including migration, urbanization, population distribution, the relationships between population, environment and resources, aging, marriage patterns, and migrants' crimes, although such contribution often did not appear in the geographical circle. Furthermore, population geographers have played an indispensable role in revitalizing population studies in China and forging its links to human geography, occupying an important position in this multi-disciplinary field. Population geographers' contribution to the areas of migration and urbanization research has been particularly significant, reflected in their leading roles in these areas' research. The paper demonstrates that as latecomers in the field after more than 20 years of isolation, population geographers in China have gone through a process of catching up and increasing engagement with developments in social sciences and increasing interaction with social scientists since the 1980 s, and have benefited greatly from it; however, there is a tendency for population geography to be increasingly alienated from the main stream human geography, a phenomenon similar to but not exactly the same as Anglo-American geography in the late 1990 s and early 2000 s. The paper argues that population geography is only half way in the course to forge the links between population studies and human geography, and it needs to return to geographical sciences to strike a healthy balance between the field of population studies and that of human geography, and promote its further development in a multi-disciplinary field.展开更多
文摘A study of precancerous gastric lesion was conducted in a randomly selected high risk population in Linqu, Shandong Province of China. 849 subjects aged from 30-64 were examined bioptically. There were 8 cases of gastric cancer, the prevalence rate was 0.9%. 169 subjects were diagnosed to be dysplasia, the prevalence rate of dysplasia was increased significantly with age. The regression equation was Y=0.47X-0.25. The prevalence of CAG was found in 36 per cent of the studied subjects and both dysplasia and CAG were more serious in the antrum than the. fundus. The results showed a natural history of precancerous gastric lesions in a high risk population in a high risk area.
文摘A series of indicators, including serum lysozyme activity, G-banding chromosome aberration (G-banding CA) analysis, sister chromatid exchanges (SCEs), chromosome aberration (CA), T-lymphocyte transformation rate (TcTR),-GT, GPT and AKP, were employed in the present survey among occupationally vinyl chloride (VC) exposed workers and inhabitants living in VC polluted area in a polyvinyl chloride (PVC) factory. The results showed that the serum lysozyme (S-LZM) activities in Group 3 (adult inhabitants exposed to 0.20 mg/m3 VC for at least 8 years), Group 2 (workers exposed to 4.1 mg/m3for at least 7 years occupationally), Group 1 (workers exposed to 25.7 mg/m3 for at least 2 years) were significantly higher than control. G-banding CA analysis showed that the total chromosome breakage rates in both Groups 1 and 2 were higher, but no difference existed between Group 3 and control. Only Group 1 was observed having higher SCEs, CA level and lower TcTR than control. AKP levels in Groups 1 and 2 were higher than control,but noγ-GT and GPT differences were found among groups. The study also suggests that G-banding CA analysis is more sensitive than CA and SCEs
文摘AIM: To determine the main visual symptoms in a Brazilian population sample, associated to refractive errors(REs) and spectacle need to suggest priorities in preventive programs.METHODS: A cross-sectional study was conducted in nine counties of the southeast region of Brazil, using a systematic sampling of households, between March 2004 and July 2005. The population was defined as individuals aged between 1 and 96 y, inhabitants of 3600 residences to be evaluated and 3012 households were included,corresponding to 8010 subjects considered for participation in the survey, of whom 7654 underwent ophthalmic examinations. The individuals were evaluated according their demographic data, eye complaints and eye examination including the RE and the need to prescribe spectacles according to age. Statistical analysis was performed using SPSS software package and descriptive analysis using 95% confidence intervals(P〈0.05). RESULTS: The main symptom detected was asthenopia, most frequent in the 2ndand 3rddecades of life, with a significant decline after the 4thdecade.Astigmatism was the RE most associated with asthenopia. Reduced near vision sight was more frequent in those ≥40y with a progressive decline thereafter.Spectacles were most frequently required in subjects of≥40 years of age.CONCLUSION: The main symptom related to the vision was asthenopia and was associated to astigmatism. The greatest need for spectacles prescription occurred after40's, mainly to correct near vision. Subjects of ≥40years old were determined to be at high risk of uncorrected REs. These observations can guide intervention programs for the Brazilian population.
文摘In this study, we analyze how vitamin D (VD) serum levels flow with latitude and throughout seasons of the year within a population sample over three years, taking into account that VD is mainly photosynthesized in the skin from sun exposure. Vitamin D levels have been measured in 80,763 patients during 2013, 2014, and 2015. To accomplish the objectives, we first perform some inference tests like two-way Analysis of Variance (ANOVA) followed by post-hoc tests. Secondly, we develop time series techniques including cross correlation calculations. Least than 10% of the sample had healthy VD levels, which should be a fact of public health major concern. The effect of the interaction between the two factors, zones and seasons, was proved by ANOVA. The mean values which are significantly different were determined by post hoc test. Furthermore, we find that mean serum VD levels, measured as 25-hydroxy-VD, follow a seasonal lag pattern of 9 weeks, a delay for minimum and maximum values after the respective equinoxes and daily sunlight duration. Reliable estimates of the population are provided in the present study, since one of the strengths is its huge sample size. We have quantitatively characterized the seasonality of serum vitamin D levels in the Argentine and the seasonal lag pattern has been determined for the study region.
文摘The aim of this population study was to identify personality traits among older (>65 years) male and female owners of cats and dogs and to compare their general health status in relation to their personality. Further, the aim was to examine whether current cat and dog ownership could be predicted by the owners’ personality and health. Data were collected from the North-Trøndelag Health Study (HUNT) in Norway. Included were a total of 1897 cat or dog owners between the ages of 65 years and 101 years. The results showed that there were a higher proportion of introverted male cat owners than extraverted ones. Moreover, a majority of women with cats reported that their health was not good. Furthermore, female cat owners who displayed higher scores on neurotic traits experienced significantly poorer health compared to those female cat owners that experienced good health. The same was true for female cat owners who considered themselves to be introverted. Neither personality nor health could predict pet-ownership, but it was more likely for older individuals (80-101 years) to own a cat than a dog. This study has shown that human personality is associated with cat and dog ownership, but there are other factors connected with pet ownership as well.
文摘It is evident that both recruitment and retention play critical roles in clinical trials. Recruitment and retention models are beginning to be analyzed worldwide in an effort to assess how to conduct studies more efficiently, all the while, allowing researchers to provide sound and ethical data to help advance medicine through clinical studies. Sponsors and sites have recognized that clinical trial enrollment must become more diverse and inclusive. In this review, we address the important topics of recruitment and retention in clinical trials. Specifically, the obstacles in regard to recruiting vulnerable populations. Methodologies to improve both the understanding of the study population and community engagement are outlined. In particular, newer strategies such as use of social media and more reliable strategies such as trust and relationship building are described in detail. A strong focus on recruitment is becoming widely recognized as being of such importance that consideration is given to this key component even during initial protocol development. Attention to recruitment and retention in the strategic planning process of clinical trials can mitigate enrollment issues that clinical researchers are experiencing.
文摘Stimulated-Raman-adiabatic-passage (STIRAP) process provides an effective technique to transfer electron population from an initial state (e.g. ground state) to excited final state for both atoms and molecules. In this paper, we present the results of the study on electron population transfer in three level system. We have analyzed the effects of various conditions on the transfer process, such as the time delay of the two laser beams, two-photon off-resonance, one-photon off-resonance and the change of relative laser intensity. The numerical result is compared with experiment, and the reasons for the effects are also given.
基金supported by the National Natural Science Foundation of China(No.60976070)the Special Funds of China Academy of Engineering Physics(No.909)
文摘A population inversion study of GaAs/AlxGa1-xAs three-quantum-well quantum cascade structures is presented. We derive the population inversion condition (PIC) of the active region (AR) and discuss the PICs on different structures by changing structural parameters such as the widths of quantum wells or barriers in the AR. For some instances, the PIC can be simplified and is proportional to the spontaneous emission lifetime between the second and the first excited states, whereas some other instances imply that the PIC is proportional to the state lifetime of the second excited state.
文摘Objective To study the population pharmacokinetic(PPK)profiles of linezolid in Chinese healthy volunteers and infected patients.Methods Linezolid 600 mg was administered to 31 Chinese healthy volunteers with a single dose and to 57 infected patients every 12 h for at least5 doses.High performance liquid chromatography was applied to determine the plasma concentration of linezol-
文摘The last 4 decades of reform and opening up have not only witnessed the rapid development of China’s social economy,but have also marked the crucial transition of China’s demographic structure from one that is mature to one that is old.As China’s population has aged rapidly in recent years,studies of aging have made worthwhile achievements documenting the process.This article mainly summarizes the development of studies on aging in China during the past 40 years and finds that research into the topic of aging during these years can be divided into three phases.The phases are characterized by particular kinds of research.Phase one,the study of aging trends and causes;phase two,the study of aging characteristics and policy responses;and phase three,the study of top-level design of aging policies and programs,and the development of integrated interdisciplinary research efforts.The five main characteristics of China’s studies on aging during the past 4 decades and five future prospects for studies on aging are discussed at the end of this paper.
基金supported in part by the National Natural Science Foundation of China(30930082,81171561 and 30972584)the National Science and Technology Major Project of China(2008ZX10002-006,2012ZX10002007001,2017ZX10202203-007 and 2017ZX10202203-008)
文摘Background and Aims:Recently,the World Health Organization adopted the first-ever global hepatitis strategy with the dream of eliminating viral hepatitis as a public health threat by 2030.However,the epidemiology and treatment rates of hepatitis C virus(HCV)infection in Western China are still unknown.Methods:A total of 111,916 adult individuals(15-96 years)who underwent the HCV-antibody(HCV-Ab)test in the Second Affiliated Hospital of Chongqing Medical University between 2013 and 2015 were included in this study.We retrospectively analyzed the electronic medical records'data for each,and the positivity of HCV-Ab and the treatment of HCV RNA-positive patients were evaluated.Results:During 2013-2015,the crude prevalence of HCVAb was 1.4%(95%CI:1.4-1.5;1,611/111,916)and the adjusted prevalence of HCV-Ab was 1.7%(95%CI:1.6-1.8),which was higher than in the 2006 national study(0.43%).The prevalence was 2-times higher in males than females(2.0%vs.1.1%,p<0.01).Notably,only 46%(434/951)of the HCV RNA-positive patients received standard peginterferon plus ribavirin treatment,with 370(82%)that completed treatment,of whom 272(74%)achieved sustained virologic response(SVR).Particularly,11%(32/292)of HCV RNA-positive patients were HBsAg-positive,and the SVR rate for them was lower than for the HBsAg-negative patients,but no significant difference was observed.Conclusions:HCV infection may have increased since 2006 in Western China.The SVR rate of peg-interferon plus ribavirin treatment was high,but the proportion of untreated HCV patients was large.Thus,more efforts need to be made by the government to create a scientific-based policy for HCV treatment and prevention.
基金National Natural Science Foundation of China,No.41471132,No.41501163
文摘This paper reviews the progress of population geography in China since the 1980 s. The review results suggest that contrary to the common perception of its invisibility and marginalized status in the field, tremendous progress has been made in population geography in China since the 1980 s. Population geographers have made significant contribution to the understanding of a wide range of population issues from geographical perspectives, including migration, urbanization, population distribution, the relationships between population, environment and resources, aging, marriage patterns, and migrants' crimes, although such contribution often did not appear in the geographical circle. Furthermore, population geographers have played an indispensable role in revitalizing population studies in China and forging its links to human geography, occupying an important position in this multi-disciplinary field. Population geographers' contribution to the areas of migration and urbanization research has been particularly significant, reflected in their leading roles in these areas' research. The paper demonstrates that as latecomers in the field after more than 20 years of isolation, population geographers in China have gone through a process of catching up and increasing engagement with developments in social sciences and increasing interaction with social scientists since the 1980 s, and have benefited greatly from it; however, there is a tendency for population geography to be increasingly alienated from the main stream human geography, a phenomenon similar to but not exactly the same as Anglo-American geography in the late 1990 s and early 2000 s. The paper argues that population geography is only half way in the course to forge the links between population studies and human geography, and it needs to return to geographical sciences to strike a healthy balance between the field of population studies and that of human geography, and promote its further development in a multi-disciplinary field.