Programmed cell death （PCD） signaling pathways are import- ant contributors to acute neurological insults such as hypox- ic-ischemic brain damage, traumatic brain injury, stroke etc. The pathogenesis of all these di...Programmed cell death （PCD） signaling pathways are import- ant contributors to acute neurological insults such as hypox- ic-ischemic brain damage, traumatic brain injury, stroke etc. The pathogenesis of all these diseases is closely linked with ab- erration of apoptotic cell death pathways. Mitochondria play a crucial role during PCD, acting as both sensors of death signals, and as initiators of biochemical path- ways, which cause cell death （Bras et al., 2005）. Cytochrome c was the firstly identified apoptogenic factor released from mitochondria into the cytosol, where it induces apoptosome formation through the activation of caspases. Other proteins, such as apoptosis inducing factor （AIF）, have been subsequently identified as mitochondrial released factors. AIF contributes to apoptotic nuclear DNA damage （Bras et al., 2005）. in a caspase-independent way展开更多
BACKGROUND: It has been shown that although brain does not contain lining endothelial lymphatic vessel, it has lymphatic drain. Anterior lymphatic system of lymphatic vessel in brain tissue plays a key role in introdu...BACKGROUND: It has been shown that although brain does not contain lining endothelial lymphatic vessel, it has lymphatic drain. Anterior lymphatic system of lymphatic vessel in brain tissue plays a key role in introducing brain interstitial fluid to lymphatic system; however, the significance of lymphatic drain and the effect on cerebral edema remains unclear. OBJECTIVE: To investigate the effect of cerebral lymphatic block on cerebral morphology and cortical evoked potential in rats. DESIGN: Randomized controlled animal study. SETTING: Institute of Cerebral Microcirculation of Taishan Medical College and Department of Neurology of Affiliated Hospital. MATERIALS: A total of 63 healthy adult male Wistar rats weighing 300-350 g were selected in this study. Forty-seven rats were used for the morphological observation induced by lymphatic drain and randomly divided into three groups: general observation group (n =12), light microscopic observation group (n =21) and electronic microscopic observation group (n =14). The rats in each group were divided into cerebral lymphatic block subgroup and sham-operation control subgroup. Sixteen rats were used for observing the effect of cerebral lymphatic block on cortical evoked potential, in which the animals were randomly divided into sham-operation group (n =6) and cerebral lymphatic block group (n =10). METHODS: The experiment was carried out in the Institute of Cerebral Microcirculation of Taishan Medical College from January to August 2003. Rats in cerebral lymphatic block group were anesthetized and separated bilateral superficial and deep cervical lymph nodes under sterile condition. Superior and inferior boarders of lymph nodes were ligated the inputting and outputting channels, respectively, and then lymph node was removed so as to establish cerebral lymphatic drain disorder models. Rats in sham-operation control group were not ligated the lymphatic vessel and removed lymph nodes, and other operations were as the same as those in cerebral lymphatic block group. Morphological changes of the brain and alterations of latency of cortical evoked potential were detected on the 1st, 2nd, 3rd, 5th, 7th, 10th and 15th days after operation under general, light microscope and electronic microscope observations. MAIN OUTCOME MEASURES: ① Cerebral morphological changes; ② latent changes of cortical evoked potential. RESULTS: A total of 63 rats were involved in the final analysis. ① Cerebral morphological changes: General observation showed that, for cerebral lymphatic block rats, the surface of brain was pale and full, and cerebral gyrus was wide and flattened sulci after cerebral lymphatic block; and cerebral tissue space prolongation, increased interstitial fluid, neuronal degeneration and necrosis, diffused phagocytes and satellitosis were observed under light microscope. Neuronal swell and necrosis, glial cell swell, apparent subcellular changes such as mitochondron were observed under electronic microscope. ② Latent changes of cortical evoked potential: As compared with sham-operation control group, latency of cortical evoked potential in cerebral lymphatic blockage group prolonged on the 5th day and 7th day after cerebral lymphatic block [(6.28±0.23), (6.97±0.35) ms; (6.23±0.22), (7.12±0.20) ms; P < 0.01]. CONCLUSION: ① Cerebral lymphatic block plays an important role in cerebral morphology, and may result in abnormality of sensitive impulse conduction and prolong latency of cortical evoked potential. ② Examination of cortical evoked potential is easy and convenient, so it is regarded as a key index for lymphatic disturbed cerebral injury.展开更多
At present,shale gas exploration and development in China is faced with some problems,such as the imperfect evaluation system of reservoir effectiveness and the limitations of reservoir evaluation system on efficient d...At present,shale gas exploration and development in China is faced with some problems,such as the imperfect evaluation system of reservoir effectiveness and the limitations of reservoir evaluation system on efficient development of shale gas.In order to improve the content and the standard of reservoir evaluation,this paper analyzed the shortcomings and challenges in the static evaluation of shale gas reservoirs on the basis of existing reservoir evaluation,and established a method for evaluating shale gas reservoir effectiveness and a scheme for classifying pore systems.Then,the dynamic evaluation parameters after shale fracturing and their effects on drainage and production measures were discussed.In addition,the potential evaluation parameters of“automatic mitigating water blocking”were studied,and a comprehensive reservoir evaluation system of“staticedynamic”combination was established.And the following research results were obtained.First,new challenges to the shale gas reservoir evaluation are emerged as the lack of in-depth study on“reservoir effectiveness,dynamic evaluation parameter system after fracturing and drainage and production measures after fracturing”,which leads to the serious lag of existing shale gas reservoir evaluation system behind production.Second,the evaluation of reservoir effectiveness is mainly presented as the evaluation on the lower limit of effective porosity,and is embodied in the influence of clay bound water and unconnected pores on the development of shale gas.Third,the development of shale gas reservoir evaluation follows the trend of refining the static reservoir evaluation parameters,defining the potential evaluation indexes of“automatic mitigating water blocking”and establishing the reservoir comprehensive evaluation system of“staticedynamic”combination.Fourth,a post-frac dynamic evaluation system is determined for the potential evaluation indexes of“automatic mitigating water blocking”(e.g.,wettability,water imbibition retention capacity,water imbibition expansion mode,expansion rate,and water imbibition cracking capacity).Fifth,a reservoir evaluation idea is put forward that“static evaluation of shale gas reservoir is the foundation and postfrac dynamic evaluation is the complement”,and a comprehensive reservoir evaluation system is established of“staticedy-namic”combination suitable for the evaluation of marine shale gas reservoirs in China.展开更多
文摘Programmed cell death （PCD） signaling pathways are import- ant contributors to acute neurological insults such as hypox- ic-ischemic brain damage, traumatic brain injury, stroke etc. The pathogenesis of all these diseases is closely linked with ab- erration of apoptotic cell death pathways. Mitochondria play a crucial role during PCD, acting as both sensors of death signals, and as initiators of biochemical path- ways, which cause cell death （Bras et al., 2005）. Cytochrome c was the firstly identified apoptogenic factor released from mitochondria into the cytosol, where it induces apoptosome formation through the activation of caspases. Other proteins, such as apoptosis inducing factor （AIF）, have been subsequently identified as mitochondrial released factors. AIF contributes to apoptotic nuclear DNA damage （Bras et al., 2005）. in a caspase-independent way
文摘BACKGROUND: It has been shown that although brain does not contain lining endothelial lymphatic vessel, it has lymphatic drain. Anterior lymphatic system of lymphatic vessel in brain tissue plays a key role in introducing brain interstitial fluid to lymphatic system; however, the significance of lymphatic drain and the effect on cerebral edema remains unclear. OBJECTIVE: To investigate the effect of cerebral lymphatic block on cerebral morphology and cortical evoked potential in rats. DESIGN: Randomized controlled animal study. SETTING: Institute of Cerebral Microcirculation of Taishan Medical College and Department of Neurology of Affiliated Hospital. MATERIALS: A total of 63 healthy adult male Wistar rats weighing 300-350 g were selected in this study. Forty-seven rats were used for the morphological observation induced by lymphatic drain and randomly divided into three groups: general observation group (n =12), light microscopic observation group (n =21) and electronic microscopic observation group (n =14). The rats in each group were divided into cerebral lymphatic block subgroup and sham-operation control subgroup. Sixteen rats were used for observing the effect of cerebral lymphatic block on cortical evoked potential, in which the animals were randomly divided into sham-operation group (n =6) and cerebral lymphatic block group (n =10). METHODS: The experiment was carried out in the Institute of Cerebral Microcirculation of Taishan Medical College from January to August 2003. Rats in cerebral lymphatic block group were anesthetized and separated bilateral superficial and deep cervical lymph nodes under sterile condition. Superior and inferior boarders of lymph nodes were ligated the inputting and outputting channels, respectively, and then lymph node was removed so as to establish cerebral lymphatic drain disorder models. Rats in sham-operation control group were not ligated the lymphatic vessel and removed lymph nodes, and other operations were as the same as those in cerebral lymphatic block group. Morphological changes of the brain and alterations of latency of cortical evoked potential were detected on the 1st, 2nd, 3rd, 5th, 7th, 10th and 15th days after operation under general, light microscope and electronic microscope observations. MAIN OUTCOME MEASURES: ① Cerebral morphological changes; ② latent changes of cortical evoked potential. RESULTS: A total of 63 rats were involved in the final analysis. ① Cerebral morphological changes: General observation showed that, for cerebral lymphatic block rats, the surface of brain was pale and full, and cerebral gyrus was wide and flattened sulci after cerebral lymphatic block; and cerebral tissue space prolongation, increased interstitial fluid, neuronal degeneration and necrosis, diffused phagocytes and satellitosis were observed under light microscope. Neuronal swell and necrosis, glial cell swell, apparent subcellular changes such as mitochondron were observed under electronic microscope. ② Latent changes of cortical evoked potential: As compared with sham-operation control group, latency of cortical evoked potential in cerebral lymphatic blockage group prolonged on the 5th day and 7th day after cerebral lymphatic block [(6.28±0.23), (6.97±0.35) ms; (6.23±0.22), (7.12±0.20) ms; P < 0.01]. CONCLUSION: ① Cerebral lymphatic block plays an important role in cerebral morphology, and may result in abnormality of sensitive impulse conduction and prolong latency of cortical evoked potential. ② Examination of cortical evoked potential is easy and convenient, so it is regarded as a key index for lymphatic disturbed cerebral injury.
基金supported by the National Natural Science Foundation of China"Characterization of the Nanopore Structure and Research on Seepage in Shale Reservoir"(No.:51674044)the Applied Basic Research Project of the Sichuan Province"Research on Intelligent Evaluation System for Key Production Zone of Marine Shale Gas(Provincial Significant Project)"(No.:2019YJ0346)+1 种基金the Significant Emerging Enginecring Project of the Sichuan Province"Research on the method of evaluating the effectiveness of fracturing the shak gas reservoir on the basis of fracturing fluid flow-back law"(No.:2019JDRC0095)the Overseas Expertise Introduction Project for Discipline Innovation(111 project)"Base of Overseas Expertise Introduction for Discipline Innovation of High-Efficiency Development of Deep-Layer Marine Shale Gas"(No.:D18016).
文摘At present,shale gas exploration and development in China is faced with some problems,such as the imperfect evaluation system of reservoir effectiveness and the limitations of reservoir evaluation system on efficient development of shale gas.In order to improve the content and the standard of reservoir evaluation,this paper analyzed the shortcomings and challenges in the static evaluation of shale gas reservoirs on the basis of existing reservoir evaluation,and established a method for evaluating shale gas reservoir effectiveness and a scheme for classifying pore systems.Then,the dynamic evaluation parameters after shale fracturing and their effects on drainage and production measures were discussed.In addition,the potential evaluation parameters of“automatic mitigating water blocking”were studied,and a comprehensive reservoir evaluation system of“staticedynamic”combination was established.And the following research results were obtained.First,new challenges to the shale gas reservoir evaluation are emerged as the lack of in-depth study on“reservoir effectiveness,dynamic evaluation parameter system after fracturing and drainage and production measures after fracturing”,which leads to the serious lag of existing shale gas reservoir evaluation system behind production.Second,the evaluation of reservoir effectiveness is mainly presented as the evaluation on the lower limit of effective porosity,and is embodied in the influence of clay bound water and unconnected pores on the development of shale gas.Third,the development of shale gas reservoir evaluation follows the trend of refining the static reservoir evaluation parameters,defining the potential evaluation indexes of“automatic mitigating water blocking”and establishing the reservoir comprehensive evaluation system of“staticedynamic”combination.Fourth,a post-frac dynamic evaluation system is determined for the potential evaluation indexes of“automatic mitigating water blocking”(e.g.,wettability,water imbibition retention capacity,water imbibition expansion mode,expansion rate,and water imbibition cracking capacity).Fifth,a reservoir evaluation idea is put forward that“static evaluation of shale gas reservoir is the foundation and postfrac dynamic evaluation is the complement”,and a comprehensive reservoir evaluation system is established of“staticedy-namic”combination suitable for the evaluation of marine shale gas reservoirs in China.
