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Change of choline compounds in sodium selenite-induced apoptosis of rats used as quantitative analysis by in vitro 9.4T MR spectroscopy 被引量:14
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作者 Zhen Cao Lin-Ping Wu +3 位作者 Yun-Xia Li Yu-Bo Guo Yao-Wen Chen Ren-Hua Wu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第24期3891-3896,共6页
AIM: To study liver cell apoptosis caused by the toxicity of selenium and observe the alteration of choline compounds using in vitro 9.4T high resolution magnetic resonance spectroscopy. METHODS: Twenty male Wistar ra... AIM: To study liver cell apoptosis caused by the toxicity of selenium and observe the alteration of choline compounds using in vitro 9.4T high resolution magnetic resonance spectroscopy. METHODS: Twenty male Wistar rats were randomly divided into two groups. The rats in the treatment group were intraperitoneally injected with sodium selenite and the control group with distilled water. All rats were sacrifi ced and the livers were dissected. 1H-MRS data were collected using in vitro 9.4T high resolution magnetic resonance spectrometer. Spectra were processed using XWINNMR and MestRe-c 4.3. HE and TUNEL staining was employed to detect and confi rm the change of liver cells. RESULTS: Good 1H-MR spectra of perchloric acid extract from liver tissue of rats were obtained. The conventional metabolites were detected and assigned. Concentrations of different ingredient choline compounds in treatment group vs control group were as follows: total choline compounds,5.08 ± 0.97 mmol/L vs 3.81 ± 1.16 mmol/L (P = 0.05); and free choline,1.07 ± 0.23 mmol/L vs 0.65 ± 0.20 mmol/L (P = 0.00). However,there was no statistical signif icance between the two groups. The hepatic sinus and cellular structure of hepatic cells in treatmentgroup were abnormal. Apoptosis of hepatic cells was confi rmed by TUNEL assay. CONCLUSION: High dose selenium compounds can cause the rat liver lesion and induce cell apoptosis in vivo. High resolution 1H-MRS in vitro can detect diversified metabolism. The changing trend for different ingredient of choline compounds is not completely the same at early period of apoptosis. 展开更多
关键词 Apoptosis of liver cell Choline compounds Sodium selenite In vitro ^1H-MRS Quantitative analysis
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Familial adenomatous polyposis and changes in the gut microbiota: New insights into colorectal cancer carcinogenesis 被引量:9
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作者 Antonio Biondi Francesco Basile Marco Vacante 《World Journal of Gastrointestinal Oncology》 SCIE 2021年第6期495-508,共14页
Patients with familial adenomatous polyposis(FAP),an autosomal dominant hereditary colorectal cancer syndrome,have a lifetime risk of developing cancer of nearly 100%.Recent studies have pointed out that the gut micro... Patients with familial adenomatous polyposis(FAP),an autosomal dominant hereditary colorectal cancer syndrome,have a lifetime risk of developing cancer of nearly 100%.Recent studies have pointed out that the gut microbiota could play a crucial role in the development of colorectal adenomas and the consequent progression to colorectal cancer.Some gut bacteria,such as Fusobacterium nucleatum,Escherichia coli,Clostridium difficile,Peptostreptococcus,and enterotoxigenic Bacteroides fragilis,could be implicated in colorectal carcinogenesis through different mechanisms,including the maintenance of a chronic inflammatory state,production of bioactive tumorigenic metabolites,and DNA damage.Studies using the adenomatous polyposis coliMin/+mouse model,which resembles FAP in most respects,have shown that specific changes in the intestinal microbial community could influence a multistep progression,the intestinal“adenoma-carcinoma sequence”,which involves mucosal barrier injury,low-grade inflammation,activation of the Wnt pathway.Therefore,modulation of gut microbiota might represent a novel therapeutic target for patients with FAP.Administration of probiotics,prebiotics,antibiotics,and nonsteroidal anti-inflammatory drugs could potentially prevent the progression of the adenoma-carcinoma sequence in FAP.The aim of this review was to summarize the best available knowledge on the role of gut microbiota in colorectal carcinogenesis in patients with FAP. 展开更多
关键词 Familial adenomatous polyposis MICROBIOTA Colorectal cancer POLYPS CARCINOGENESIS BACTERIA
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Short and long term neuro-behavioral alterations in type 1 diabetes mellitus pediatric population 被引量:2
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作者 Edna Litmanovitch Ronny Geva Marianna Rachmiel 《World Journal of Diabetes》 SCIE CAS 2015年第2期259-270,共12页
Type 1 diabetes mellitus(T1DM) is one of the most prevalent chronic conditions affecting individuals under the age of 18 years, with increasing incidence worldwide, especially among very young age groups, younger than... Type 1 diabetes mellitus(T1DM) is one of the most prevalent chronic conditions affecting individuals under the age of 18 years, with increasing incidence worldwide, especially among very young age groups, younger than 5. There is still no cure for the disease, and therapeutic goals and guidelines are a challenge. Currently, despite T1 DM intensive management and technological interventions in therapy, the majority of pediatric patients do not achieve glycemic control goals. This leads to a potential prognosis of long term diabetic complications, nephrological, cardiac, ophthalmological and neurological. Unfortunately, the neurological manifestations, including neurocognitive and behavioral complications, may present soon after disease onset, during childhood and adolescence. These manifestations may be prominent, but at times subtle, thus they are often not reported by patients or physicians as related to the diabetes. Furthermore, the metabolic mechanism for such manifestations has been inconsistent and difficult to interpret in practical clinical care, as reported in several reviews on the topic of brain and T1 DM. However, new technological methods for brain assessment, as well as the introduction of continuous glucose monitoring, provide new insights and information regarding brain related manifestations and glycemic variability and control parameters, which may impact the clinical care of children and youth with T1 DM. This paper provides a comprehensive review of the most recently reported behavioral, cognitive domains, sleep related, electrophysiological, and structural alterations in children and adolescences from a novel point of view. The review focuses on reported impairments based on duration of T1 DM, its timeline, and modifiable disease related risk parameters. These findings are not without controversy, and limitations of data are presented in addition to recommendations for future research direction. 展开更多
关键词 Type 1 DIABETES MELLITUS COGNITIVE BEHAVIORAL Brain Alterations Children Adolescences
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The formation of explosive volcanos at the circum-Pacific convergent margin during the last century 被引量:2
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作者 Fanfan TIAN Kun WANG +1 位作者 Guozhi XIE Weidong SUN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第1期75-83,共9页
The circum-Pacific convergent margin is known as"the Ring of Fire",with abundant volcano eruptions.Large eruptions are rare but very disastrous.It remains obscure how are large explosive volcanos formed and ... The circum-Pacific convergent margin is known as"the Ring of Fire",with abundant volcano eruptions.Large eruptions are rare but very disastrous.It remains obscure how are large explosive volcanos formed and where are the danger zones.Three largest eruptions since 1900,the Hunga Tonga-Hunga Ha’apai,the Mt.Pinatubo,and the Novarupta were found to be associated with subductions of volatile-rich sediments and located close to slab windows.Among them,the Hunga Tonga-Hunga Ha’apai is close to subducting seamount chains;the Mt.Pinatubo is right next to subducting fossil ridges.Both seamount chains and fossil ridges have water depths much shallower than the carbonate compensation depths(CCD)in the Pacific Ocean.Seismic image shows that a seamount is subducting towards the Novarupta volcano.Subduction of volatile-rich sediments and a slab window nearby are the two most important favorable conditions for catastrophic eruptions.Slab windows expose the mantle wedge to the hot asthenosphere,which increases the temperature and dramatically promotes the partial melting of the carbonate-fluxed domains,forming volatile-rich magmas that powered explosive eruptions. 展开更多
关键词 large explosive volcanos subducting seamount chains volatile-rich sediments slab windows TONGA
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Is 1.28 parts per million biomarker specific for neural progenitor cells? 被引量:2
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作者 Zhifeng Xu Chongyang Shen +9 位作者 Haiqiang Zhu Yaowen Chen Linping Wu Peng Huang YeyuXiao Zhiwei Shen Li Pang Xiuqin Guo Lian Ma Renhua Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第15期1125-1129,共5页
Nuclear magnetic resonance-visible mobile lipid, at 1.28 parts per million (ppm), is thought to be due to mobile lipid droplets formed in cells and has been considered unique for neural progenitor cells. However, th... Nuclear magnetic resonance-visible mobile lipid, at 1.28 parts per million (ppm), is thought to be due to mobile lipid droplets formed in cells and has been considered unique for neural progenitor cells. However, this idea remains controversial. The present study examined the 1.28 ppm biomarker in other stem cells and non-stem cells, and explored the relationship between 1.28 ppm biomarker and mobile lipid droplets. 1H nuclear magnetic resonance spectroscopy of EC109 cells, mesenchymal stem cells (MSCs) and adipogenic cells differentiated from MSCs was performed. Results show that 1.28 ppm biomarker was observed in human MSCs, but was absent from EC109 cells. Following adipogenic differentiation induced for 2 weeks, the 1.28 ppm biomarker climbed remarkably, with mobile lipid droplet generation, suggesting that the 1.28 ppm biomarker is not specific for neural progenitor cells because it is also observed in MSCs and adipogenic-induced differentiated cells. Moreover, it is possible to monitor MSCs differentiation following cell transplantation, using 1.28 ppm biomarker changes. 展开更多
关键词 magnetic resonance spectroscopy mesenchymal stem cell adipogenic differentiation BIOMARKER lipid droplet
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Characterization of subduction initiation 被引量:2
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作者 Weidong SUN Lipeng ZHANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第1期72-74,共3页
Compression is required for all kinds of subduction initiations,which may cause either subsidence or uplift,depending on the ages of the oceanic plates.Subduction initiations associated with the old oceanic crust tend... Compression is required for all kinds of subduction initiations,which may cause either subsidence or uplift,depending on the ages of the oceanic plates.Subduction initiations associated with the old oceanic crust tend to amplify preexisting subsidence by compression,whereas those associated with young oceanic plates may result in uplift. 展开更多
关键词 subduction initiation induced and spontaneous west Pacific plate tectonics
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SHEDDING LIGHT ON LIFE:OPTICAL ASSESSMENT OF MITOCHONDRIAL FUNCTION AND TISSUE VITALITY IN BIOLOGY AND MEDICINE 被引量:2
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作者 AVRAHAM MAYEVSKY 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2008年第1期71-83,共13页
The involvement of mitochondrial dysfunction in various pathophysiological conditions,developed in experimental and clinical situations,is widely documented.Nevertheless,real time monitoring of mitochondrial function ... The involvement of mitochondrial dysfunction in various pathophysiological conditions,developed in experimental and clinical situations,is widely documented.Nevertheless,real time monitoring of mitochondrial function In-vivo is very rare.The pressing question is how the mitochondria of intact tissues behave under In-vivo conditions as compared to isolated mitochondria that had been described by Chance and Williams over 50 years ago.This subject has been recently discussed in detail(Mayevsky and Rogatsky 2007).We reviewed the subject of evaluating mitochondrial function by monitoring NADH fluorescence together with microcirculatory blood flow,Hemoglobin oxygenation and tissue reflectance.These 4 parameters represent the vitality of the tissue and could be monitored in vivo,using optical spectroscopy,in animal models as well as in clinical practice.It is a well known physiological hypothesis that,under emergency conditions,the sympathetic nervous system will give preference to the most vital organs in the body,namely the brain,heart and adrenal glands.The less vital organs,such as the skin,GI-tract,and Urethral wall,will become hypoperfused and their mitochondrial activity will be inhibited.The monitoring of the less vital organs may reveal critical tissue conditions that may manifest an early phase of body deterioration.The aim of the current presentation is to review the experimental and preliminary clinical results accumulated using a new integrated medical device–the“CritiView”which enabled,for the first time,monitoring 4 parameters from the tissue using a single optical probe.The CritiView is a computerized optical device that integrates hardware and software in order to provide real time information on tissue vitality.In preliminary clinical testing,we used a 3-way Foley catheter that includes a bundle of optical fibers enabling the monitoring of the 4 parameters,representing the vitality of the urethral wall(a less vital organ).We found that the exposure of patients to metabolic imbalances in the operation room led to changes in tissue blood flow and inhibition of mitochondrial function in the urethral wall.In conclusion,the new device“CritiView”could provide reliable,real time data on mitochondrial function and tissue vitality in experimental animals as well as in patients. 展开更多
关键词 ORGANS representing HARDWARE
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X-ray absorption near the edge structure and x-ray photoelectron spectroscopy studies on pyrite prepared by thermally sulfurizing iron films 被引量:1
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作者 张辉 刘应书 +3 位作者 王宝义 魏龙 奎热西 钱海杰 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第7期2734-2738,共5页
This paper reports how pyrite films were prepared by thermal sulfurization of magnetron sputtered iron films and characterized by X-ray absorption near edge structure spectra and X-ray photoelectron spectroscopy on a ... This paper reports how pyrite films were prepared by thermal sulfurization of magnetron sputtered iron films and characterized by X-ray absorption near edge structure spectra and X-ray photoelectron spectroscopy on a 4B9B beam line at the Beijing Synchrotron Radiation Facility. The band gap of the pyrite agrees well with the optical band gap obtained by a spectrophotometer. The octahedral symmetry of pyrite leads to the splitting of the d orbit into t2g and eg levels. The high spin and low spin states were analysed through the difference of electron exchange interaction and the orbital crystal field. Only when the crystal field splitting is higher than 1.5 eV, the two weak peaks above the white lines can appear, and this was approved by experiments in the present work. 展开更多
关键词 X-ray absorption near the edge structure spectra X-ray photoelectron spectroscopy iron pyrite films solar cells
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Human umbilical mesenchymal stem cell and its adipogenic differentiation:Profiling by nuclear magnetic resonance spectroscopy 被引量:8
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作者 Zhi-Feng Xu, Ai-Zhen Pan, Fang Yong, Chong-Yang Shen, Yao-Wen Chen Ren-Hua Wu 《World Journal of Stem Cells》 2012年第4期21-27,共7页
AIM: To study the metabolic profile of human umbilical mesenchymal stem cells (HUMSC) and adipogenic differentiation by nuclear magnetic resonance (NMR) spectroscopy.
关键词 Human umbilical mesenchymal stem cell Adipogenic differentiation MR spectroscopy BIOMARKER
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REAL-TIME MONITORING OF MITOCHONDRIAL FUNCTION AND CEREBRAL BLOOD FLOW FOLLOWING FOCAL ISCHEMIA IN RATS 被引量:1
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作者 AMIR LIVNAT MICHAEL TOLMASOV +1 位作者 EFRAT BARBIRO-MICHAELY AVRAHAM MAYEVSKY 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2008年第1期63-69,共7页
Focal ischemia due to reduction of cerebral blood flow(CBF),creates 2 zones of damage:the core area,which suffers severe damage,and penumbra area,which surrounds the core and suffers intermediate levels of injury.Obje... Focal ischemia due to reduction of cerebral blood flow(CBF),creates 2 zones of damage:the core area,which suffers severe damage,and penumbra area,which surrounds the core and suffers intermediate levels of injury.Objectives:A novel method is introduced,which evaluates mitochondrial function in the core and in the penumbra,during focal cerebral ischemia.Methods:Wistar rats underwent focal cerebral ischemia by middle cerebral artery occlusion(MCAO)for 60 minutes,followed by 60 minutes of reperfusion.Mitochondrial function was assessed by a unique Multi-Site—Multi-Parametric(MSMP)monitoring system,which measures mitochondrial NADH using fluorometric technique,and CBF using Laser Doppler Flowmetry(LDF).Results:At the onset of occlusion,CBF dropped and NADH increased significantly only in the right hemisphere.CBF levels were significantly lower and NADH significantly higher in the core than in the penumbra.After reperfusion,CBF and NADH recovered correspondingly to the intensity of ischemia.Conclusion:Application of the MSMP system can add significant information for the understanding of the cerebral metabolic state under ischemic conditions,with an emphasis on mitochondrial function. 展开更多
关键词 Mitochondrial function cerebral blood flow focal ischemia
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Sex and Death:Identification of Feedback Neuromodulation Balancing Reproduction and Survival 被引量:1
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作者 Can Gao Chao Guo +4 位作者 Qionglin Peng Jie Cao Galit Shohat-Ophir Dong Liu Yufeng Pan 《Neuroscience Bulletin》 SCIE CAS CSCD 2020年第12期1429-1440,共12页
Some semelparous organisms in nature mate as many times as they can in a single reproductive episode before death,while most iteroparous species including humans avoid such suicidal reproductive behavior.Animals natur... Some semelparous organisms in nature mate as many times as they can in a single reproductive episode before death,while most iteroparous species including humans avoid such suicidal reproductive behavior.Animals naturally pursue more sex and the possible fatal consequence of excessive sex must be orchestrated by negative feedback signals in iteroparous species,yet very little is known about the regulatory mechanisms.Here we used Drosophila male sexual behavior as a model system to study how excessive sex may kill males and how the nervous system reacts to prevent death by sex.We found that continuous sexual activity by activating the fruitlessexpressing neurons induced a fixed multi-step behavioral pattern ending with male death.We further found negative feedback in the fly brain to prevent suicidal sexual behavior by expression changes of the neurotransmitters acetylcholine and gamma-aminobutyric acid,and neuropeptide F.These findings are crucial to understand the molecular underpinnings of how different organisms choose reproductive strategies and balance reproduction and survival. 展开更多
关键词 DROSOPHILA REPRODUCTION SURVIVAL NPF GABA ACETYLCHOLINE
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MITOCHONDRIAL FUNCTION AND TISSUE VIABILITY IN VIVO:FROM ANIMAL EXPERIMENTS TO CLINICAL APPLICATIONS.FORTY YEARS OF FRUITFUL COLLABORATION WITH BRITTON CHANCE
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作者 AVRAHAM MAYEVSKY 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2011年第4期337-359,共23页
The involvement of mitochondrial dysfunction in many pathophysiological conditions and human diseases is well documented.In order to evaluate mitochondrial function in vitro,many experimental systems have been develop... The involvement of mitochondrial dysfunction in many pathophysiological conditions and human diseases is well documented.In order to evaluate mitochondrial function in vitro,many experimental systems have been developed.Nevertheless the number of in vivo monitoring systems for the evaluation of mitochondrial activities in intact animals and patients is relatively limited.The pioneering development of the conceptual and technological aspects ofmitochondrial monitoring,in vitro and in vivo,was done by the late Prof.Britton Chance(July 24,1913November 16,2010)since the early 1950s.It was my privilege to join his laboratory in 1972 and collaborate with him for almost four decades.The main achievements of our collaboration are presented in this paper.Our activities included cycles of technology development,followed by its applications to study various pathophysiological conditions.In the initial stage,thefirstfiber-opticbased NADHfluorometer was developed.This device enabled us to monitor various organs in anesthetized animals aswell as the brain of nonanesthetized small animals.Later on,the addition of various physiological parameters to NADH monitoring enabled us to correlate mitochondrial function with other cellular functions.The application of the developed technology to clinical situations was a major interest of Prof.Chance and indeed this goal was achieved in the last decade.As of today,the basic tool forNADHmonitoring and the large database of results are available for large-scale experimental and clinical applications. 展开更多
关键词 NADHfluorescence in vivo multiparametric brain monitoring mitochondrial redox state mitochondrial dysfunction tissue energy metabolism
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EFFECTS OF SEVERE HEMORRHAGE ON IN VIVO BRAIN AND SMALL INTESTINE MITOCHONDRIAL NADH AND MICROCIRCULATORY BLOOD FLOW
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作者 MIRA M.MANDELBAUM EFRAT BARBIRO-MICHAELY +1 位作者 MICHAEL TOLMASOV AVRAHAM MAYEVSKY 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2008年第2期177-183,共7页
Severe body stress induced by hypoxemia and hypotension may lead to total body energy state deterioration.The perfusion of the most vital organs is maintained at the expense of“less vital”organs.In the present study... Severe body stress induced by hypoxemia and hypotension may lead to total body energy state deterioration.The perfusion of the most vital organs is maintained at the expense of“less vital”organs.In the present study,we used a multi-site multiparametric(MSMP)monitoring system for real-time evaluation of tissue blood flow(TBF)and mitochondrial NADH fluorescence of the brain and the small intestine following hemorrhage.In Group 1,uncontrolled hemorrhage,mean arterial pressure(MAP)was decreased to 40mmHg within 2 minutes and shed blood was re-infused after 30minutes.In Group 2,controlled hemorrhage,during the 30minutes of hemorrhage,MAP was kept at 40mmHg.During hemorrhage,in both groups,the intestinal TBF and NADH deteriorated,while the brain remained relatively well protected.In Group 1,all parameters partly recovered within the hemorrhage phase,while in Group 2,complete recovery occurred only after resuscitation.At the end of the experiment,both models showed a decrease in intestinal viability(TBF decreased,NADH increased),while the brain metabolic state in Group 2 declined slightly.Our unique multi-parametric monitoring device demonstrated that,under hemorrhage,the small intestine responded entirely differently from the brain.This may suggest the potential usefulness of the monitoring of less vital organs,as proxy organs,in critical conditions such as massive hemorrhage.The present study also highlights the importance of mitochondrial function monitoring in similar conditions in the clinical environment. 展开更多
关键词 Mitochondrial dysfunction multiparametric monitoring Laser Doppler Flowmetery fluorometric NADH monitoring
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HYPERBARIC HYPEROXIA AND THE BRAIN IN VIVO:THE BALANCE BETWEEN THERAPY AND TOXICITY
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作者 JUDITH SONN ELHANAN MEIROVITHZ AVRAHAM MAYEVSKY 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2008年第2期185-193,共9页
Hyperbaric oxygenation(HBO)treatment protocols utilize low pressures up to 3ATA.Higher pressures may induce side effects such as convulsions due to brain toxicity.The optimal HBO pressure allowing for maximal therapy ... Hyperbaric oxygenation(HBO)treatment protocols utilize low pressures up to 3ATA.Higher pressures may induce side effects such as convulsions due to brain toxicity.The optimal HBO pressure allowing for maximal therapy and minimal toxicity is under controversy.However,it can be evaluated by monitoring oxygen delivery,saturation,and consumption.In this study,the monitoring system fixed on the rats’brain cortex included a time-sharing fluorometer-reflectometer for monitoring mitochondrial NADH and hemoglobin oxygenation(HbO_(2))combined with Laser Doppler Flowmetry(LDF)for blood-flow monitoring.Rats were located in a hyperbaric chamber and exposed to different pressures.The HBO pressure caused an increase in HbO_(2)and a decrease in NADH in proportion to the increase in hyperbaric pressure,up to a nearly maximum effect at 2.5ATA.At 6ATA,15 minutes before convulsions started,blood volume and NADH started to increase,while tissue O_(2)supply by hemoglobin remained stable.Oxygen pool includes oxygen dissolved in the plasma and also bounded to hemoglobin.Above 2.5ATA,hemoglobin is fully saturated and the oxygen pool nourishment derives only from the oxygen dissolved in the plasma,exceeding the physiological ability for autoregulation;hence,homeostasis is disturbed and convulsions appear.This information is vital because pressures around 2.5ATA–3ATA are standard clinically applied pressures used to treat most of the pathophysiological problems considering the potential benefit which must be balanced against the potential toxicity.This study enables,for the first time,to evaluate the oxygenation level of hemoglobin in the microcirculation.Furthermore,our study showed that additional oxygen pressure(above 2.5ATA)caused brain oxygen toxicity within a short variable period of time after the pressure elevation. 展开更多
关键词 NADH redox state brain tissue hemoglobin oxygenation HBO therapy HBO toxicity
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Theoretical study on order–disorder phase transition of CH3NH3PbCl3
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作者 Jing Chang Zhen-Yi Jiang +3 位作者 Qi Song Lei Chen Yan-Min Lin Bo Zhou 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第11期264-267,共4页
Order–disorder phase transitions for CH3NH3PbCl3 are studied with density functional theory. Our calculations show that the disorder is manifested in two aspects in the cubic phase, namely, the disorder of orientatio... Order–disorder phase transitions for CH3NH3PbCl3 are studied with density functional theory. Our calculations show that the disorder is manifested in two aspects in the cubic phase, namely, the disorder of orientation and rotation of organic groups. Organic groups of [CH3] and [NH3] in cubic crystals can easily rotate around its C3 axis. At the same time,[CH3NH3]^+ organic groups can also orient to different spatial directions due to the weak interactions between organic group and inorganic frame. Our results show that its possible phase transition path starts from the deviation of organic groups from the crystal c-axis. Its structural transition changes from disordered cubic phase to hydrogen-only disordered tetragonal structure in the process of decreasing symmetry. The disordered high temperature cubic phase can be expressed as a statistical average of substructures we rebuilt. The electrostatic repulsive force between adjacent organic groups triggers out the formation of low temperature phase on cooling. 展开更多
关键词 order–disorder state phase transition ROTATION BARRIER DIPOLE interaction
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HOW DOES ANESTHESIA AFFECT VARIOUS LEVELS OF EXPERIMENTAL TRAUMATIC BRAIN INJURY?
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作者 BARBIRO-MICHAELY EFRAT MANOR TAMAR +1 位作者 ROGATSKY GENNADY MAYEVSKY AVRAHAM 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2011年第4期409-420,共12页
The use of anesthetics is a well-known treatment for severely injured patients.In the present study we tested the pathophysiology of several levels of injury damage in a rat model and also tested the effect of Equithe... The use of anesthetics is a well-known treatment for severely injured patients.In the present study we tested the pathophysiology of several levels of injury damage in a rat model and also tested the effect of Equithesin on brain vitality in these models.Traumatic Brain Injury(TBI)was induced using thefluid percussion injury model in four levels:mild,moderate and two levels of severe TBI.Brain real-time evaluation was performed by the multiparametric monitoring assembly(MPA)which enable cerebral bloodflow(CBF)monitoring by laser Dopplerflowmetry,mitochondrial NADH(Nicotinamide adenine dinucleotide)monitoring by thefluorometric technique,ionic homehostasis using special mini-electrodes,intracranial pressure(ICP)by the ICP camino device and needle electrodes for ECoG(Electrocorticogram)recording.Our results showed high correlation between the level of impact and the extent of changes in the physiological properties of the injury as indicated by the changes in all parameters monitored using the MPA device.Moreover,Equithesin improved CBF,ionic extracellular level and mitochondrial redox state following mild and moderate TBI while in severe TBI,Equithesin did not improve the metabolic state of the cerebral cortex,although it decreased the mortality rate from 66%to 20%,and following extra-severe TBI level,Equithesin did not improve survival rate.In conclusion it seems that Equithesin's protective effect exists under mild to moderate levels of injury and not in case of severe injuries. 展开更多
关键词 Cerebral bloodflow mitochondrial NADH multiparametric monitoring
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Structure and stability of neutral and cationic AlnO clusters
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作者 杨鹏 葛建华 姜振益 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第4期1014-1019,共6页
In this paper various structural possibilities for AlnO neutral and cationic isomers were investigated by using the B3LYP/6-311G(3df) method. Calculations of this paper predicted the existence of a number of previou... In this paper various structural possibilities for AlnO neutral and cationic isomers were investigated by using the B3LYP/6-311G(3df) method. Calculations of this paper predicted the existence of a number of previously unknown isomers. The stabilities of the AlnO (n = 2 - 7) clusters with even n are greater than those with odd n, however the stabilities Of cationic ions have the opposite odd-even alternation. The mass spectra observations of Al17O^+ and Al19O^+ ions support our theoretical predictions on their stabilities. 展开更多
关键词 AlnO clusters geometric configuration ionization potentials STABILITY
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Why not change classical treatments for glioblastoma in elderly patients?
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作者 Eduardo Perez-Campos Javier Arjona Perez +3 位作者 Laura Perez-Campos Mayoral Itandehui Gallegos Velasco Pedro Hernandez Cruz Primitivo Gonzalez Olivera 《World Journal of Experimental Medicine》 2013年第4期50-55,共6页
In consideration of the poor results obtained with conventional treatments, a review of alternative treatments for elderly patients with glioblastoma was researched in this study. The proposal considers the eliminatio... In consideration of the poor results obtained with conventional treatments, a review of alternative treatments for elderly patients with glioblastoma was researched in this study. The proposal considers the elimination of human cytomegalovirus, modifying the immune response, arresting growths, blocking some signaling pathways, and modulating the effects of oxygen reactive species. 展开更多
关键词 GLIOBLASTOMA Treatment ELDERLY patients GLIOMA GLIOBLASTOMA
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Histological Analysis and Morphometric Changes after Autologous Fat Grafting in Large Volumes on Pigs
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作者 Hector Giancarlo Torres-Nuño Walter Angel Trujillo-Rangel +4 位作者 Jorge Barrera-Alcocer Miriam Méndez del Villar Diana Mercedes Hernández-Corona Sylvia Elena Totsuka-Sutto Leonel García Benavides 《Journal of Cosmetics, Dermatological Sciences and Applications》 2021年第4期371-380,共10页
Nowadays, fat transfer is an accepted technique that has been popularized in clinical practice, during which large volumes of fat are strategically relocated to increase and improve the contour of the body. In the pre... Nowadays, fat transfer is an accepted technique that has been popularized in clinical practice, during which large volumes of fat are strategically relocated to increase and improve the contour of the body. In the present study, we investigated the histological and morphometric changes after large volumes of fat were grafted within the subcutaneous cellular tissue. An experimental study was designed using four 3-month-old male pigs. One hundred cc of decanted fat tissue was transferred into the right leg. Volume augmentation achieved by auto lipo-injecting within the subcutaneous cellular tissue persisted up to two months. Although there is a reduction in cell number and size, an increased amount of extracellular matrix and the presence of oily cysts and microcalcifications were observed. <strong>Conclusion:</strong> The volume augmentation, which is achieved by autologous fat transfer in large quantities in subcutaneous cellular tissue, can remain for months. 展开更多
关键词 Autologous Fat Transfer Adipose Tissue Transplant Autologous Fat Injection Gluteal Augmentation
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Coupling between the Cenozoic west Pacific subduction initiation and decreases of atmospheric carbon dioxides
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作者 Guozhi Xie Fanfan Tian +3 位作者 Kun Wang Yuanyuan Xiao Tianyu Chen Weidong Sun 《Acta Geochimica》 EI CAS CSCD 2023年第3期387-392,共6页
At the beginning of the Cenozoic,the atmospheric CO_(2)concentration increased rapidly from~2000 ppmv at 60 Ma to~4600 ppmv at 51 Ma,which is 5–10 times higher than the present value,and then continuous declined from... At the beginning of the Cenozoic,the atmospheric CO_(2)concentration increased rapidly from~2000 ppmv at 60 Ma to~4600 ppmv at 51 Ma,which is 5–10 times higher than the present value,and then continuous declined from~51 to 34 Ma.The cause of this phenomenon is still not well understood.In this study,we demonstrate that the initiation of Cenozoic west Pacific plate subduction,triggered by the hard collision in the Tibetan Plateau,occurred at approximately 51 Ma,coinciding with the tipping point.The water depths of the Pacific subduction zones are mostly below the carbonate compensation depths,while those of the Neo-Tethys were much shallower before the collision and caused far more carbonate subducting.Additionally,more volcanic ashes erupted from the west Pacific subduction zones,which consume CO_(2).The average annual west Pacific volvano eruption is 1.11 km~3,which is higher than previous estimations.The amount of annual CO_(2)absorbed by chemical weathering of additional west Pacific volcanic ashes could be comparable to the silicate weathering by the global river.We propose that the initiation of the western Pacific subduction controlled the long-term reduction of atmospheric CO_(2)concentration. 展开更多
关键词 Subduction initiation in the west Pacific Collision of the Neo-Tethys Volcano eruption rates Cenozoic CO_(2)declining Carbonate compensation depths Chemical weathering
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