Alzheimer's disease(AD)is a prevalent neurodegenerative disease characterized by cognitive decline in the early stage.Mild cognitive impairment(MCI)is considered as an intermediate stage between normal aging and A...Alzheimer's disease(AD)is a prevalent neurodegenerative disease characterized by cognitive decline in the early stage.Mild cognitive impairment(MCI)is considered as an intermediate stage between normal aging and AD.In recent years,studies related to resting-state functional MRI(rs-fMRI)indicated that the occurrence and development process of MCI and AD might be closely linked to spontaneous brain activity and alterations in functional connectivity among brain regions,and rs-fMRI could provide important reference for specific diagnosis and early treatment of MCI and AD.The research progresses of rs-fMRI for MCI and AD were reviewed in this article.展开更多
Objective:To summarize and analyze the clinical and histopathological features of chronic acalculous cholecystitis (CAC) and to investigate the diagnosis and surgical treatment of chronic acalculous cholecystit.Method...Objective:To summarize and analyze the clinical and histopathological features of chronic acalculous cholecystitis (CAC) and to investigate the diagnosis and surgical treatment of chronic acalculous cholecystit.Methods:The study subjects were 39 patients with chronic biliary symptoms but no evidence of stones in the gallbladder by B ultrasonography and magnetic resonance cholopancreatography (MRCP) (CAC group).The CCC group consisted of 66 patients taken randomly from concurrent all patients of chronic calculous cholecystitis (CCC).All patients accepted fibergastroscopy,B ultrasonography,MRCP,laboratory examination preoperatively.We retrospectively analyzed the clinical features,B ultrasonography and MRCP findings,histopathological results and clinical outcomes between the two groups.Results:All the 39 patients were diagnosed by clinical symptoms,B ultrasonography,fatty meal gallbladder contractability studies under ultrasound,fibergastroscopy and magnetic resonance cholangiopancreatography (MRCP),what's more,they were pathologically verified postoperatively.In all patients,there was a complete absence of gallbladder wall contractability.Mucosa epithelial defect was found in 21 patients in CAC group (53.8%) and 16 patients in CCC group (24.2%) respectively (P<0.005).Thickened arteriole wall was found in 29 patients in CAC group (74.4%) and none patient in CCC group (P<0.0001).Thickened gallbladder wall (4 mm or more in thickness) was found in 33 patients in CAC group (84.6%) and 28 patients in CCC group (42.4%) respectively (P<0.005).Bile stasis was found in 23 patients in CAC group (59.0%) and 14 patients in CCC group (21.2%) respectively by ultrasonography preoperatively and confirmed in operation (P<0.005).The outcomes of cholecystectomy,expressed as total or near total relief,was similar in the two groups.No statistically significant differences were observed between patients with CAC (90%) and CCC (80%),the P-value >0.05.Conclusion:Chronic acalculous cholecystitis could be diagnosed by symptoms,ultrasound,fatty meal gallbladder contractability studies under untrasoundand MRCP.The optimal treatment of chronic acalculous cholecystitis characterized by thickened arteriole wall and mucosa epithelial defect is cholecystectomy.展开更多
Spectrum sharing offers the opportunity for promising efficiency gains, and it will be a valuable tool in the era of future radios.To address this issue, we develop a multi-user cognitive radio sharing network based o...Spectrum sharing offers the opportunity for promising efficiency gains, and it will be a valuable tool in the era of future radios.To address this issue, we develop a multi-user cognitive radio sharing network based on opportunistic spectrum access and propose a new spectrum sharing strategy.The objective of our interest is to obtain the number of secondary users who can coexist peacefully with primary users to improve the utility of licensed spectrum, at the same time maximize the total goodput under the interference temperature and SINR constraints.Through analysis and simulation, the new strategy of spectrum sharing does improve the goodput performance as well as guarantee the Quality of Service(QoS) of primary and secondary users.展开更多
From a social constructivist perspective, this study explores Chinese EFL learners' identity construction in their engagement with English songs and movies. Analysis of English journals written by 16 first-year En...From a social constructivist perspective, this study explores Chinese EFL learners' identity construction in their engagement with English songs and movies. Analysis of English journals written by 16 first-year English majors from a comprehensive university shows that through investment in various imagined communities (Norton 2001), the learners exercised agency in creating multiple identities beyond the dichotomy between 'target culture' and 'native culture.'展开更多
Functional magnetic resonance imaging （fMRI） technique has been more widely applied to related studies of acupuncture central integration mechanisms with the advantages of non-invasion and real-time monitor, etc. Di...Functional magnetic resonance imaging （fMRI） technique has been more widely applied to related studies of acupuncture central integration mechanisms with the advantages of non-invasion and real-time monitor, etc. Discovery of resting state brain activities and the default brain network challenges to the acupuncture-related studies based on traditional block design. The paper reviews some obvious advances of fMRI in studies of acupoint specificity, and research methods and progresses of the resting state brain functional network in recent years, and raises the thinking about leading the resting state fMRI and the brain functional network into acupuncture-related studies, in the hope of probing into the effect and modulation of acupuncture on the default network, promoting development of acupuncture mechanism studies and strengthening scientific basis of acupuncture and moxibustion theories.展开更多
OBJECTIVE: To study cognitive function and cerebral metabolic changes in patients with transient global amnesia (TGA). METHODS: Three patients with TGA were given mini-mental state examination (MMSE), revised Wechsler...OBJECTIVE: To study cognitive function and cerebral metabolic changes in patients with transient global amnesia (TGA). METHODS: Three patients with TGA were given mini-mental state examination (MMSE), revised Wechsler memory scale (WMS-R) examination and magnetic resonance imaging (MRI) scans after they had been diagnosed as TGA. Using (18)F labelled deoxyglucose as tracer, patients were given a positron emission tomography (PET) examination at different periods during recovery. RESULTS: No obvious abnormality was found in MMSE and MRI scans in the three patients. However, WMS-R examination and cerebral PET imaging displayed cognitive dysfunction of varying degrees and low metabolism in local areas related to memory in 2 of 3 patients. CONCLUSIONS: In TGA patients, cognitive function and cerebral metabolic levels are closely correlated with duration of symptoms. It is necessary to stop the TGA attack as quickly as possible early time.展开更多
Mild cognitive impairment （MCI） is common in patients with Parkinson＇s disease （PD）, yet the underlying neural mechanisms of this disease state remain unclear. We investigated alterations in the spontaneous brain...Mild cognitive impairment （MCI） is common in patients with Parkinson＇s disease （PD）, yet the underlying neural mechanisms of this disease state remain unclear. We investigated alterations in the spontaneous brain activity of PD patients with MCI （PD-MCI） relative to cognitively normal PD patients （PD-CN） and healthy control （HC） subjects. In this work, 13 PD-MCI patients, 16 PD-CN patients, and 16 HC subjects completed resting state functional MRI. Spontaneous brain activity was measured by calculating amplitude of low frequency fluctuation （ALFF） values across the whole brain. Between-group differences and correlations between ALFF values and cognitive test scores were analyzed. ALFF values decreased in the right superior temporal gyrus and increased in the left middle temporal gyrus and left superior frontal gyms of PD-MCI patients compared with PD-CN patients. In the PD-MCI group, ALFF values in the left middle temporal gyrus were negatively correlated with Montreal Cognitive Assessment and vocabulary test scores, and the ALFF values in the left superior frontal gyms were negatively correlated with vocabulary test scores. Our study demonstrates that PD-MCI is associated with abnormal spontaneous brain activity in the temporal and frontal lobes. These findings inform the underlying neural mechanism of cognitive impairment in PD.展开更多
文摘Alzheimer's disease(AD)is a prevalent neurodegenerative disease characterized by cognitive decline in the early stage.Mild cognitive impairment(MCI)is considered as an intermediate stage between normal aging and AD.In recent years,studies related to resting-state functional MRI(rs-fMRI)indicated that the occurrence and development process of MCI and AD might be closely linked to spontaneous brain activity and alterations in functional connectivity among brain regions,and rs-fMRI could provide important reference for specific diagnosis and early treatment of MCI and AD.The research progresses of rs-fMRI for MCI and AD were reviewed in this article.
文摘Objective:To summarize and analyze the clinical and histopathological features of chronic acalculous cholecystitis (CAC) and to investigate the diagnosis and surgical treatment of chronic acalculous cholecystit.Methods:The study subjects were 39 patients with chronic biliary symptoms but no evidence of stones in the gallbladder by B ultrasonography and magnetic resonance cholopancreatography (MRCP) (CAC group).The CCC group consisted of 66 patients taken randomly from concurrent all patients of chronic calculous cholecystitis (CCC).All patients accepted fibergastroscopy,B ultrasonography,MRCP,laboratory examination preoperatively.We retrospectively analyzed the clinical features,B ultrasonography and MRCP findings,histopathological results and clinical outcomes between the two groups.Results:All the 39 patients were diagnosed by clinical symptoms,B ultrasonography,fatty meal gallbladder contractability studies under ultrasound,fibergastroscopy and magnetic resonance cholangiopancreatography (MRCP),what's more,they were pathologically verified postoperatively.In all patients,there was a complete absence of gallbladder wall contractability.Mucosa epithelial defect was found in 21 patients in CAC group (53.8%) and 16 patients in CCC group (24.2%) respectively (P<0.005).Thickened arteriole wall was found in 29 patients in CAC group (74.4%) and none patient in CCC group (P<0.0001).Thickened gallbladder wall (4 mm or more in thickness) was found in 33 patients in CAC group (84.6%) and 28 patients in CCC group (42.4%) respectively (P<0.005).Bile stasis was found in 23 patients in CAC group (59.0%) and 14 patients in CCC group (21.2%) respectively by ultrasonography preoperatively and confirmed in operation (P<0.005).The outcomes of cholecystectomy,expressed as total or near total relief,was similar in the two groups.No statistically significant differences were observed between patients with CAC (90%) and CCC (80%),the P-value >0.05.Conclusion:Chronic acalculous cholecystitis could be diagnosed by symptoms,ultrasound,fatty meal gallbladder contractability studies under untrasoundand MRCP.The optimal treatment of chronic acalculous cholecystitis characterized by thickened arteriole wall and mucosa epithelial defect is cholecystectomy.
基金Supported by the National Natural Science Foundation of China (No.60772062)Key Research Project of MOE of China (No.206055).
文摘Spectrum sharing offers the opportunity for promising efficiency gains, and it will be a valuable tool in the era of future radios.To address this issue, we develop a multi-user cognitive radio sharing network based on opportunistic spectrum access and propose a new spectrum sharing strategy.The objective of our interest is to obtain the number of secondary users who can coexist peacefully with primary users to improve the utility of licensed spectrum, at the same time maximize the total goodput under the interference temperature and SINR constraints.Through analysis and simulation, the new strategy of spectrum sharing does improve the goodput performance as well as guarantee the Quality of Service(QoS) of primary and secondary users.
基金the project"The Social Psychology of English Language Learning by Chinese Students-Alongitudinal study of the first two years in university"the National Grant for Social Sciences in China (projectnumber 05BYY007)
文摘From a social constructivist perspective, this study explores Chinese EFL learners' identity construction in their engagement with English songs and movies. Analysis of English journals written by 16 first-year English majors from a comprehensive university shows that through investment in various imagined communities (Norton 2001), the learners exercised agency in creating multiple identities beyond the dichotomy between 'target culture' and 'native culture.'
基金Supported by National Key Basic Research Development Grant(973 Grant):2006 CB 504501Natural Science Foundation of China Grants:30772835
文摘Functional magnetic resonance imaging （fMRI） technique has been more widely applied to related studies of acupuncture central integration mechanisms with the advantages of non-invasion and real-time monitor, etc. Discovery of resting state brain activities and the default brain network challenges to the acupuncture-related studies based on traditional block design. The paper reviews some obvious advances of fMRI in studies of acupoint specificity, and research methods and progresses of the resting state brain functional network in recent years, and raises the thinking about leading the resting state fMRI and the brain functional network into acupuncture-related studies, in the hope of probing into the effect and modulation of acupuncture on the default network, promoting development of acupuncture mechanism studies and strengthening scientific basis of acupuncture and moxibustion theories.
文摘OBJECTIVE: To study cognitive function and cerebral metabolic changes in patients with transient global amnesia (TGA). METHODS: Three patients with TGA were given mini-mental state examination (MMSE), revised Wechsler memory scale (WMS-R) examination and magnetic resonance imaging (MRI) scans after they had been diagnosed as TGA. Using (18)F labelled deoxyglucose as tracer, patients were given a positron emission tomography (PET) examination at different periods during recovery. RESULTS: No obvious abnormality was found in MMSE and MRI scans in the three patients. However, WMS-R examination and cerebral PET imaging displayed cognitive dysfunction of varying degrees and low metabolism in local areas related to memory in 2 of 3 patients. CONCLUSIONS: In TGA patients, cognitive function and cerebral metabolic levels are closely correlated with duration of symptoms. It is necessary to stop the TGA attack as quickly as possible early time.
基金supported by the National Natural Science Foundation of China(81271429 and 81571228)
文摘Mild cognitive impairment （MCI） is common in patients with Parkinson＇s disease （PD）, yet the underlying neural mechanisms of this disease state remain unclear. We investigated alterations in the spontaneous brain activity of PD patients with MCI （PD-MCI） relative to cognitively normal PD patients （PD-CN） and healthy control （HC） subjects. In this work, 13 PD-MCI patients, 16 PD-CN patients, and 16 HC subjects completed resting state functional MRI. Spontaneous brain activity was measured by calculating amplitude of low frequency fluctuation （ALFF） values across the whole brain. Between-group differences and correlations between ALFF values and cognitive test scores were analyzed. ALFF values decreased in the right superior temporal gyrus and increased in the left middle temporal gyrus and left superior frontal gyms of PD-MCI patients compared with PD-CN patients. In the PD-MCI group, ALFF values in the left middle temporal gyrus were negatively correlated with Montreal Cognitive Assessment and vocabulary test scores, and the ALFF values in the left superior frontal gyms were negatively correlated with vocabulary test scores. Our study demonstrates that PD-MCI is associated with abnormal spontaneous brain activity in the temporal and frontal lobes. These findings inform the underlying neural mechanism of cognitive impairment in PD.
