AIM:To investigate the distribution pattern of lymphatic vessels and microvessels in sporadic colorectal carcinoma(SCRC)and their relationship to metastasis and prognosis.METHODS:The lymphatic vessel density(LVD)and m...AIM:To investigate the distribution pattern of lymphatic vessels and microvessels in sporadic colorectal carcinoma(SCRC)and their relationship to metastasis and prognosis.METHODS:The lymphatic vessel density(LVD)and microvessel density(MVD)in tumor tissue obtained from 132 patients with primary SCRC,including 74 with metastases and 58 without metastases,were evaluated by immunohistochemistry using antibodies directed against D2-40 and yon Willebrand factor(vWF).RESULTS:(1)The lymphatic vessels and microvessels at central portions of SCRC often had a reticular architecture with numerous tiny and ill-defined lumina,while those at tumor borders had large and open lumina.The LVD and MVD were both obviously higher in colorectal cancer patients with metastases than in those without(P〈0.001).(2)For each one lymphatic vessel increased,there was a 1.45-fold increase in the risk of metastasis in SCRC.The specificity and sensitivity of LVD in predicting metastasis or non-metastasis in SCRC were 71.62%and 56.90%,respectively,and the corresponding LVD was 5.For each one microvessel increased,there was a 1.11-fold increase in the risk of metastasis in SCRC.The specificity and sensitivity of MVD were 66.22%and 51.72%,respectively.(3)Double labeling immunohistochemistry showed D2-40 immunoreactivity to be specific for lymphatic vessels.(4)Univariate analysis indicated that high LVD,high MVD,as well as co-accounting of high LVD and high MVD were associated with patient's poor disease-free survival(Puni〈0.05);multivariate analysis indicated that co-accounting of LVD and MVD was an independent prognostic factor of colorectal cancer,CONCLUSION:D2-40 is a new specific antibody for lymphatic endothelial cells.Lymphogenesis and angiogenesis are commonly seen in SCRC,especially at tumor borders.The detection of LVD and MVD at tumor borders may be useful in predicting metastasis and prognosis in patients with SCRC,and,in particular,coaccounting of LVD and MVD might be a useful prognostic factor in SCRC.展开更多
To implement the computation of AHP （Analytic Hierarchy Process） automatically, make the implementation independence on the platform, and to convenient the service composition and service computation, this study imp...To implement the computation of AHP （Analytic Hierarchy Process） automatically, make the implementation independence on the platform, and to convenient the service composition and service computation, this study implemented AHP model as a Web service and stored the evaluation information as XML form. This paper introduces the overall demands of AHP evaluation system firstly, and then presents some key technologies to implement AHP evaluation system, including mainly AHP evaluation index architecture based on XML, the class of AHP model, the Web service encapsulation of AHP, the publication and invocation of AHP and the client application. At last, the system is used to analyze the impact factors of online consumption behavior.展开更多
Blade rubbing faults cause detrimental impact on the operation of aeroengines. Most of the existing studies on blade rubbing in the shaft-disk-blade-casing(SDBC) system have overlooked the elastic deformation of the b...Blade rubbing faults cause detrimental impact on the operation of aeroengines. Most of the existing studies on blade rubbing in the shaft-disk-blade-casing(SDBC) system have overlooked the elastic deformation of the blade, while some only consider the whirl of the rotor, neglecting its spin. To address these limitations, this paper proposes a dynamic model with large rotation for the SDBC system. The model incorporates the spin and whirl of the rotor, enabling the realistic reproduction of multiblade rubbing faults. To verify the accuracy of the SDBC model with large rotation and demonstrate its capability to effectively consider the rotational effects such as the centrifugal stiffening and gyroscopic effects, the natural characteristics and dynamic responses of the proposed model are compared with those obtained from reported research and experimental results. Furthermore, the effects of the rotating speed, contact stiffness,and blade number on the dynamic characteristics of the SDBC system with multi-blade rubbing are investigated. The results indicate that the phase angle between the rotor deflection and the unbalance excitation force increases with the increasing rotating speed,which significantly influences the rubbing penetration of each blade. The natural frequency of the SDBC system with rubbing constrain can be observed in the acceleration response of the casing and the torsional response of the shaft, and the frequency is related to the contact stiffness. Moreover, the vibration amplitude increases significantly with the product of the blade number under rubbing, and the rotating frequency approaches the natural frequency of the SDBC system. The proposed model can provide valuable insight for the fault diagnosis of rubbing in bladed rotating machinery.展开更多
The previous pharmacokinetic methods can be only limited to drug analysis in vitro, which provide less information on the distribution and metabolismof drugs, and limit the interpretation and assessment of pharmacokin...The previous pharmacokinetic methods can be only limited to drug analysis in vitro, which provide less information on the distribution and metabolismof drugs, and limit the interpretation and assessment of pharmacokinetics, the determination of metabolic principles, and evaluation of treatment effect. The objective of the study was to investigate the pharmacokinetic characteristics of gene recombination angiogenesis inhibitor Kringle 5 in vivo. The SPECT/CT and specific^(131)I-Kringle 5 marked by Iodogen method were both applied to explore the pharmacokinetic characteristics of^(131)I-Kringle 5 in vivo, and to investigate the dynamic distributions of^(131)I-Kringle 5 in target organs. Labeling recombinant angiogenesis inhibitor Kringle 5 using131 I with longer half-life and imaging in vivo using SPECT instead of PET,could overcome the limitations of previous methods. When the doses of^(131)I-Kringle 5 were 10.0, 7.5 and5.0 g/kg, respectively, the two-compartment open models can be determined within all the metabolic process in vivo. There were no significant differences in t1/2α, t1/2β, apparent volume of distribution and CL between those three levels. The ratio of AUC(0 1)among three different groups of 10.0, 7.5 and 5.0 g/kg was 2.56:1.44:1.0, which was close to the ratio(2:1.5:1.0). It could be clear that in the range of 5.0–10.0 g/kg, Kringle 5 was characterized by the first-order pharmacokinetics. Approximately 30 min after^(131)I-Kringle 5 was injected,^(131)I-Kringle 5 could be observed to concentrate in the heart, kidneys, liver and other organs by means of planar imaging and tomography. After 1 h of being injected, more radionuclide retained in the bladder, but not in intestinal. It could be concluded that^(131)I-Kringle 5 is mainly excreted through the kidneys. About 2 h after the injection of^(131)I-Kringle 5, the radionuclide in the heart, kidneys,liver and other organs was gradually reduced, while more radionuclide was concentrated in the bladder.The radionuclide was completely metabolized within 24 h, and the distribution of radioactivity in rats was similar to normal levels. In our study, the specific marker^(131)I-Kringle 5 and SPECT/CT were successfully used to explore pharmacokinetic characteristics of Kringle 5 in rats. The study could provide a new evaluation platform of the specific, in vivo and real-time functional imaging and pharmacokinetics for the clinical application of^(131)I-Kringle 5.展开更多
Recognizing the risk of fluvial bank erosion is an important challenge to ensure the early warning and prevention or control of bank collapse in river catchments,including in the Yangtze River.This study introduces a ...Recognizing the risk of fluvial bank erosion is an important challenge to ensure the early warning and prevention or control of bank collapse in river catchments,including in the Yangtze River.This study introduces a geomorphons-based algorithm to extract river bank erosion information by adjusting the flatness from multibeam echo-sounding data.The algorithm maps ten subaqueous morphological elements,including the slope,footslope,flat,ridge,peak,valley,pit,spur,hollow,and shoulder.Twentyone flatness values were used to build an interpretation strategy for the subaqueous features of riverbank erosion.The results show that the bank scarp,which is the erosion carrier,is covered by slope cells when the flatness is 10°.The scour pits and bank scars are indicated by pit cells near the bank and hollow cells in the bank slope at a flatness of 0°.Fluvial subaqueous dunes are considered an important factor accelerating bank erosion,particularly those near the bank toe;the critical flatness of the dunes was evaluated as 3°.The distribution of subaqueous morphological elements was analyzed and used to map the bank erosion inventory.The analysis results revealed that the near-bank zone,with a relatively large water depth,is prone to form large scour pits and a long bank scarp.Arc collapse tends to occur at the long bank scarp to shorten its length.The varied assignment of flatness values among terrestrial,marine,and fluvial environments is discussed,concluding that diversified flatness values significantly enable fluvial subaqueous morphology recognition.Consequently,this study provides a reference for the flatness-based recognition of fluvial morphological elements and enhances the targeting of subaqueous signs and risks of bank failure with a range of multibeam bathymetric data.展开更多
This paper focuses on the role and application of AWL in science-related subjects,namely the issue of whether or not students in science-related majors is advantaged or disadvantaged in using the Academic Word List(AW...This paper focuses on the role and application of AWL in science-related subjects,namely the issue of whether or not students in science-related majors is advantaged or disadvantaged in using the Academic Word List(AWL)in their academic writing assignments as the imbalance of word frequency in AWL.Participants(n=18)are obliged to answer the Questionnaire.Furthermore,if needed,a brief interview would be arranged on some uncertain questions.Results show that learning and acquiring academic vocabulary would benefit participants in research articles,while AWL is inadequate for students in science-related disciplines in their academic writing.We claim that students in science-related majors may be disadvantaged than other majors’students in using Coxhead’s Academic Word List,and a wordlist screened out from science-related corpus perhaps more suitable for ESP students.Meanwhile,AWL,as a role of reference,would aid language learning or acquisition.展开更多
A large gas field with reserves of nearly 200 billion m^(3)dBZ19-6dwas discovered in the Bozhong Depression in the Bohai Bay Basin in 2018.There is a considerable difference between the amount of natural gas that woul...A large gas field with reserves of nearly 200 billion m^(3)dBZ19-6dwas discovered in the Bozhong Depression in the Bohai Bay Basin in 2018.There is a considerable difference between the amount of natural gas that would traditionally be expected to be generated by the thermal degradation of low-mature kerogens and the resources that have been confirmed by exploration.Therefore,the geochemical characteristics and the genesis of gas have become crucial aspects of investigating deep natural gas in the Bozhong Depression.The deep gas in the depression is predominantly methane.Its dry coefficient(C_(1)/C_(1-5))ranges from 0.73 to 0.94,which is generally characterized as wet gas.The main nonhydrocarbon gases are CO_(2)(1.26%-52.00%)and N_(2)(0.1%-0.74%),with traces of H_(2)S(10.44×10^(-6)-36.63×10^(-6) ppm).The natural gases are thermogenic oil-type gases from the Shahejie and Dongying Formations.The deep natural gas in the Bozhong Depression is mainly derived from kerogen degradation,with contributions from oil cracking gas in the BZ1/19 and BZ2/3 structures.Complex carbon isotopic reversals are caused by the filling and mixing of natural gas with different maturities from the same source,evaporative fractionation due to the filling of late-stage high-mature natural gas,and Rayleigh fractionation under deep exogenous temperatures in the presence of transition metals.Combining the analysis of the fluid properties of natural gas,the evaluation of the performance of the migration system,and the understanding of the accumulation background indicates a high possibility that the gas was supplied from multiple hydrocarbon sources over long distances in the late stage.Thus,advantageous traps with high temperatures,close proximity to source kitchens,and favorable migration conditions are the preferred targets for future natural gas exploration in the Bozhong Depression.展开更多
BACKGROUNO： Studies have indicated that the more certain etiological factors of vascular dementia are the sites, size and number of cerebrovascular lesions, but there are arguments all the time in the relationship of...BACKGROUNO： Studies have indicated that the more certain etiological factors of vascular dementia are the sites, size and number of cerebrovascular lesions, but there are arguments all the time in the relationship of genetic factors, especially apolipoprotein E gene, with the occurrence and development of vascular dementia. OBJECTIVE： To analyze the relationship between the polymorphism of apolipoprotein E gene and vascular dementia in stroke patients. OESIGN ： A non-randomized grouped comparative observation at the same time SETTING ： The Laboratory of Neurology, the Second Affiliated Hospital of Chongqing University of Medical Sciences. PARTICIPANTS： Totally 121 inpatients with stroke were selected from the Department of Neurology, the Second Affiliated Hospital of Chongqing University of Medical Sciences from January 2000 to December 2001. All the patients were accorded with the diagnostic standards for cerebrovascular diseases set by the Second National Academic Meeting for Cerebrovascular Disease, and confirmed by cranial CT or MRI. According to with vascular dementia or not, they were divided into vascular dementia group （n =58） and non-vascular dementia group （n =63）. In the vascular dementia group, there were 37 males and 21 females, the average age was （59＋8） years. They were all in accordance with the standard of the third edition of Diagnostic and Statistical Manual of Mental Disorders （DMS-Ⅲ）, without conscious disturbance and language disorder; hospitalized within 3 days after the attack of cerebrovascular disease. In the non-vascular dementia group, there were 37 males and 26 females, the average age was （59±9.5） years. They all had no intellectual disturbance within 3 months after the attack of cerebrovascular disease. All the subjects agreed to supply blood samples for the experiment. METHOOS： ①Fasting venous blood （2 mL） was drawn from each patient in the morning to extract DNA. The frequencies of apolipoprotein E genotypes and alleles were detected with polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP）. ② Gene frequency was calculated using the gene calculation, genotype or allele frequency were compared using the Chi-square test. MAIN OUTCOME MEASURES ： The frequencies of apolipoprotein E genotypes and alleles were compared between the two groups. RESULTS ： All the 121 patients were involved in the analysis of results. Five genotypes of apolipoprotein E gene were detected, and ε2/2 genotype was not detected. The frequency of ε3/3 was the highest in both groups, the frequencies of ε4/4 genotype and ε4 allele were obviously higher in the vascular dementia group [9%（5/58）, 24.1%] than in the non-vascular dementia group [3% （2/58）, 19.0%, P 〈 0.05]. The genotype frequencies of ε2/2,ε2/4, ε3/3, ε2/3 and ε3/4 and the allele frequencies of ε2 and ε3 in the vascular dementia group [0, 2%（1/58）, 57%（33/58）, 3%（2/58）, 29%（17/58）; 2.6%, 73.3%] were not obviously different from those in the non-vascular dementia group [0, 2%（1/58）, 59%（37/63）, 6%（4/63）, 30%（19/63）; 4.0%, 77.0%, P〉 0.05]. CONCLUSION ： The ε4/4 genotype of apolipoprotein E gene is closely correlated with the occurrence of vascular dementia, the ε4 allele may be a genetic susceptible factor of vascular dementia.展开更多
基金Supported by the a grant from the Sciences and Techni-que Development Foundation of Shanghai,No.064119512,024119010
文摘AIM:To investigate the distribution pattern of lymphatic vessels and microvessels in sporadic colorectal carcinoma(SCRC)and their relationship to metastasis and prognosis.METHODS:The lymphatic vessel density(LVD)and microvessel density(MVD)in tumor tissue obtained from 132 patients with primary SCRC,including 74 with metastases and 58 without metastases,were evaluated by immunohistochemistry using antibodies directed against D2-40 and yon Willebrand factor(vWF).RESULTS:(1)The lymphatic vessels and microvessels at central portions of SCRC often had a reticular architecture with numerous tiny and ill-defined lumina,while those at tumor borders had large and open lumina.The LVD and MVD were both obviously higher in colorectal cancer patients with metastases than in those without(P〈0.001).(2)For each one lymphatic vessel increased,there was a 1.45-fold increase in the risk of metastasis in SCRC.The specificity and sensitivity of LVD in predicting metastasis or non-metastasis in SCRC were 71.62%and 56.90%,respectively,and the corresponding LVD was 5.For each one microvessel increased,there was a 1.11-fold increase in the risk of metastasis in SCRC.The specificity and sensitivity of MVD were 66.22%and 51.72%,respectively.(3)Double labeling immunohistochemistry showed D2-40 immunoreactivity to be specific for lymphatic vessels.(4)Univariate analysis indicated that high LVD,high MVD,as well as co-accounting of high LVD and high MVD were associated with patient's poor disease-free survival(Puni〈0.05);multivariate analysis indicated that co-accounting of LVD and MVD was an independent prognostic factor of colorectal cancer,CONCLUSION:D2-40 is a new specific antibody for lymphatic endothelial cells.Lymphogenesis and angiogenesis are commonly seen in SCRC,especially at tumor borders.The detection of LVD and MVD at tumor borders may be useful in predicting metastasis and prognosis in patients with SCRC,and,in particular,coaccounting of LVD and MVD might be a useful prognostic factor in SCRC.
基金the National Natural Science Foundation of China(70772073)the Natural Science Foundation of Shanghai (07ZR14003)+1 种基金the Social Science Programming Foundation of Shanghai(2007BZH001)Excellent Young Teachers Follow-Up Scientific Research Foundation of Shanghai Fisheries University(A-0212-07-0132)
文摘To implement the computation of AHP （Analytic Hierarchy Process） automatically, make the implementation independence on the platform, and to convenient the service composition and service computation, this study implemented AHP model as a Web service and stored the evaluation information as XML form. This paper introduces the overall demands of AHP evaluation system firstly, and then presents some key technologies to implement AHP evaluation system, including mainly AHP evaluation index architecture based on XML, the class of AHP model, the Web service encapsulation of AHP, the publication and invocation of AHP and the client application. At last, the system is used to analyze the impact factors of online consumption behavior.
基金Project supported by the National Science and Technology Major Project of China (No. 2017-V-0009)the National Natural Science Foundation of China (Nos. 12032015 and 12121002)the National Funding Program for Postdoctoral Researchers of China (No. GZC20231586)。
文摘Blade rubbing faults cause detrimental impact on the operation of aeroengines. Most of the existing studies on blade rubbing in the shaft-disk-blade-casing(SDBC) system have overlooked the elastic deformation of the blade, while some only consider the whirl of the rotor, neglecting its spin. To address these limitations, this paper proposes a dynamic model with large rotation for the SDBC system. The model incorporates the spin and whirl of the rotor, enabling the realistic reproduction of multiblade rubbing faults. To verify the accuracy of the SDBC model with large rotation and demonstrate its capability to effectively consider the rotational effects such as the centrifugal stiffening and gyroscopic effects, the natural characteristics and dynamic responses of the proposed model are compared with those obtained from reported research and experimental results. Furthermore, the effects of the rotating speed, contact stiffness,and blade number on the dynamic characteristics of the SDBC system with multi-blade rubbing are investigated. The results indicate that the phase angle between the rotor deflection and the unbalance excitation force increases with the increasing rotating speed,which significantly influences the rubbing penetration of each blade. The natural frequency of the SDBC system with rubbing constrain can be observed in the acceleration response of the casing and the torsional response of the shaft, and the frequency is related to the contact stiffness. Moreover, the vibration amplitude increases significantly with the product of the blade number under rubbing, and the rotating frequency approaches the natural frequency of the SDBC system. The proposed model can provide valuable insight for the fault diagnosis of rubbing in bladed rotating machinery.
文摘The previous pharmacokinetic methods can be only limited to drug analysis in vitro, which provide less information on the distribution and metabolismof drugs, and limit the interpretation and assessment of pharmacokinetics, the determination of metabolic principles, and evaluation of treatment effect. The objective of the study was to investigate the pharmacokinetic characteristics of gene recombination angiogenesis inhibitor Kringle 5 in vivo. The SPECT/CT and specific^(131)I-Kringle 5 marked by Iodogen method were both applied to explore the pharmacokinetic characteristics of^(131)I-Kringle 5 in vivo, and to investigate the dynamic distributions of^(131)I-Kringle 5 in target organs. Labeling recombinant angiogenesis inhibitor Kringle 5 using131 I with longer half-life and imaging in vivo using SPECT instead of PET,could overcome the limitations of previous methods. When the doses of^(131)I-Kringle 5 were 10.0, 7.5 and5.0 g/kg, respectively, the two-compartment open models can be determined within all the metabolic process in vivo. There were no significant differences in t1/2α, t1/2β, apparent volume of distribution and CL between those three levels. The ratio of AUC(0 1)among three different groups of 10.0, 7.5 and 5.0 g/kg was 2.56:1.44:1.0, which was close to the ratio(2:1.5:1.0). It could be clear that in the range of 5.0–10.0 g/kg, Kringle 5 was characterized by the first-order pharmacokinetics. Approximately 30 min after^(131)I-Kringle 5 was injected,^(131)I-Kringle 5 could be observed to concentrate in the heart, kidneys, liver and other organs by means of planar imaging and tomography. After 1 h of being injected, more radionuclide retained in the bladder, but not in intestinal. It could be concluded that^(131)I-Kringle 5 is mainly excreted through the kidneys. About 2 h after the injection of^(131)I-Kringle 5, the radionuclide in the heart, kidneys,liver and other organs was gradually reduced, while more radionuclide was concentrated in the bladder.The radionuclide was completely metabolized within 24 h, and the distribution of radioactivity in rats was similar to normal levels. In our study, the specific marker^(131)I-Kringle 5 and SPECT/CT were successfully used to explore pharmacokinetic characteristics of Kringle 5 in rats. The study could provide a new evaluation platform of the specific, in vivo and real-time functional imaging and pharmacokinetics for the clinical application of^(131)I-Kringle 5.
基金This study was funded by the joint project supported by National Natural Science Foundation of China(NSFC)-Netherlands Organisation for Scientific Research(NWO)-Engineering and Physical Sciences Research Council(EPSRC)(51761135023)the China Geological Survey(DD20190260)NSFC(41476075).
文摘Recognizing the risk of fluvial bank erosion is an important challenge to ensure the early warning and prevention or control of bank collapse in river catchments,including in the Yangtze River.This study introduces a geomorphons-based algorithm to extract river bank erosion information by adjusting the flatness from multibeam echo-sounding data.The algorithm maps ten subaqueous morphological elements,including the slope,footslope,flat,ridge,peak,valley,pit,spur,hollow,and shoulder.Twentyone flatness values were used to build an interpretation strategy for the subaqueous features of riverbank erosion.The results show that the bank scarp,which is the erosion carrier,is covered by slope cells when the flatness is 10°.The scour pits and bank scars are indicated by pit cells near the bank and hollow cells in the bank slope at a flatness of 0°.Fluvial subaqueous dunes are considered an important factor accelerating bank erosion,particularly those near the bank toe;the critical flatness of the dunes was evaluated as 3°.The distribution of subaqueous morphological elements was analyzed and used to map the bank erosion inventory.The analysis results revealed that the near-bank zone,with a relatively large water depth,is prone to form large scour pits and a long bank scarp.Arc collapse tends to occur at the long bank scarp to shorten its length.The varied assignment of flatness values among terrestrial,marine,and fluvial environments is discussed,concluding that diversified flatness values significantly enable fluvial subaqueous morphology recognition.Consequently,this study provides a reference for the flatness-based recognition of fluvial morphological elements and enhances the targeting of subaqueous signs and risks of bank failure with a range of multibeam bathymetric data.
文摘This paper focuses on the role and application of AWL in science-related subjects,namely the issue of whether or not students in science-related majors is advantaged or disadvantaged in using the Academic Word List(AWL)in their academic writing assignments as the imbalance of word frequency in AWL.Participants(n=18)are obliged to answer the Questionnaire.Furthermore,if needed,a brief interview would be arranged on some uncertain questions.Results show that learning and acquiring academic vocabulary would benefit participants in research articles,while AWL is inadequate for students in science-related disciplines in their academic writing.We claim that students in science-related majors may be disadvantaged than other majors’students in using Coxhead’s Academic Word List,and a wordlist screened out from science-related corpus perhaps more suitable for ESP students.Meanwhile,AWL,as a role of reference,would aid language learning or acquisition.
文摘A large gas field with reserves of nearly 200 billion m^(3)dBZ19-6dwas discovered in the Bozhong Depression in the Bohai Bay Basin in 2018.There is a considerable difference between the amount of natural gas that would traditionally be expected to be generated by the thermal degradation of low-mature kerogens and the resources that have been confirmed by exploration.Therefore,the geochemical characteristics and the genesis of gas have become crucial aspects of investigating deep natural gas in the Bozhong Depression.The deep gas in the depression is predominantly methane.Its dry coefficient(C_(1)/C_(1-5))ranges from 0.73 to 0.94,which is generally characterized as wet gas.The main nonhydrocarbon gases are CO_(2)(1.26%-52.00%)and N_(2)(0.1%-0.74%),with traces of H_(2)S(10.44×10^(-6)-36.63×10^(-6) ppm).The natural gases are thermogenic oil-type gases from the Shahejie and Dongying Formations.The deep natural gas in the Bozhong Depression is mainly derived from kerogen degradation,with contributions from oil cracking gas in the BZ1/19 and BZ2/3 structures.Complex carbon isotopic reversals are caused by the filling and mixing of natural gas with different maturities from the same source,evaporative fractionation due to the filling of late-stage high-mature natural gas,and Rayleigh fractionation under deep exogenous temperatures in the presence of transition metals.Combining the analysis of the fluid properties of natural gas,the evaluation of the performance of the migration system,and the understanding of the accumulation background indicates a high possibility that the gas was supplied from multiple hydrocarbon sources over long distances in the late stage.Thus,advantageous traps with high temperatures,close proximity to source kitchens,and favorable migration conditions are the preferred targets for future natural gas exploration in the Bozhong Depression.
文摘BACKGROUNO： Studies have indicated that the more certain etiological factors of vascular dementia are the sites, size and number of cerebrovascular lesions, but there are arguments all the time in the relationship of genetic factors, especially apolipoprotein E gene, with the occurrence and development of vascular dementia. OBJECTIVE： To analyze the relationship between the polymorphism of apolipoprotein E gene and vascular dementia in stroke patients. OESIGN ： A non-randomized grouped comparative observation at the same time SETTING ： The Laboratory of Neurology, the Second Affiliated Hospital of Chongqing University of Medical Sciences. PARTICIPANTS： Totally 121 inpatients with stroke were selected from the Department of Neurology, the Second Affiliated Hospital of Chongqing University of Medical Sciences from January 2000 to December 2001. All the patients were accorded with the diagnostic standards for cerebrovascular diseases set by the Second National Academic Meeting for Cerebrovascular Disease, and confirmed by cranial CT or MRI. According to with vascular dementia or not, they were divided into vascular dementia group （n =58） and non-vascular dementia group （n =63）. In the vascular dementia group, there were 37 males and 21 females, the average age was （59＋8） years. They were all in accordance with the standard of the third edition of Diagnostic and Statistical Manual of Mental Disorders （DMS-Ⅲ）, without conscious disturbance and language disorder; hospitalized within 3 days after the attack of cerebrovascular disease. In the non-vascular dementia group, there were 37 males and 26 females, the average age was （59±9.5） years. They all had no intellectual disturbance within 3 months after the attack of cerebrovascular disease. All the subjects agreed to supply blood samples for the experiment. METHOOS： ①Fasting venous blood （2 mL） was drawn from each patient in the morning to extract DNA. The frequencies of apolipoprotein E genotypes and alleles were detected with polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP）. ② Gene frequency was calculated using the gene calculation, genotype or allele frequency were compared using the Chi-square test. MAIN OUTCOME MEASURES ： The frequencies of apolipoprotein E genotypes and alleles were compared between the two groups. RESULTS ： All the 121 patients were involved in the analysis of results. Five genotypes of apolipoprotein E gene were detected, and ε2/2 genotype was not detected. The frequency of ε3/3 was the highest in both groups, the frequencies of ε4/4 genotype and ε4 allele were obviously higher in the vascular dementia group [9%（5/58）, 24.1%] than in the non-vascular dementia group [3% （2/58）, 19.0%, P 〈 0.05]. The genotype frequencies of ε2/2,ε2/4, ε3/3, ε2/3 and ε3/4 and the allele frequencies of ε2 and ε3 in the vascular dementia group [0, 2%（1/58）, 57%（33/58）, 3%（2/58）, 29%（17/58）; 2.6%, 73.3%] were not obviously different from those in the non-vascular dementia group [0, 2%（1/58）, 59%（37/63）, 6%（4/63）, 30%（19/63）; 4.0%, 77.0%, P〉 0.05]. CONCLUSION ： The ε4/4 genotype of apolipoprotein E gene is closely correlated with the occurrence of vascular dementia, the ε4 allele may be a genetic susceptible factor of vascular dementia.
