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The Process of Tiger Disappearance in Guizhou
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作者 Qin Yang Cheng Xu +1 位作者 Qingqing He Lingling Deng 《Research in Ecology》 CAS 2024年第1期28-39,共12页
In this paper,the authors collected officially published literature on the South China tiger(Panthera tigris amoyensis)in Guizhou from 1900 to 1980,from which we extracted information on its historical distribution an... In this paper,the authors collected officially published literature on the South China tiger(Panthera tigris amoyensis)in Guizhou from 1900 to 1980,from which we extracted information on its historical distribution and population size,and collected data on the tiger skin trade after 1950,the change in subtropical broad-leaved evergreen forest cover,and demographic data in the relevant databases.GIS mapping was used to visualize the distribution range of the South China tiger in Guizhou Province during the period 1900–1980 and to discuss the history of its disappearance in Guizhou and its driving factors.The results show that in 1900,the South China tiger was distributed throughout 82 cities and counties in nine prefectures and municipalities in the province;the number of documented South China tiger distribution sites in 1900–1950 decreased to 48 compared to 1900;the number of counties with South China tigers in 1950–1980 further decreased and became extinct in some areas;and in the 1990s,the South China tiger became extinct in the wild in Guizhou.The main reasons for the extinction of the South China tiger in the wild in Guizhou are:on the one hand,with the socio-economic development of Guizhou Province,the population has increased dramatically,the magnitude of the demand for natural resources has increased,and in order to satisfy this demand,human activities,such as coal mining and clearing of mountains for planting,have been intensified,resulting in the reduction of the coverage rate of the subtropical broad-leaved evergreen forests,which has resulted in the extreme loss of the habitat of the South China tiger;on the other hand,the insufficient protection efforts and protection measures for this species in the country before the 1980s,which were subjected to anthropogenic hunting,were also factors leading to the extinction of this species in the wild in Guizhou Province.As a big cat at the top of the food chain,the distribution of the South China tiger can reflect the history of the natural environment in the region.By analyzing and discussing the distribution history of the South China tiger population in Guizhou Province,the significance of this case is to provide a scientific basis for the future conservation of biodiversity and the development of ecological restoration measures in the karst mountains of southern China. 展开更多
关键词 The South China tiger DISAPPEARANCE Broad-leaved evergreen forests
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Application effect of phloroglucinol injection in elderly patients with spastic abdominal pain in emergency department 被引量:1
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作者 Yu-Fei Liu Jian Chen 《World Journal of Clinical Cases》 SCIE 2023年第23期5440-5446,共7页
BACKGROUND Although norepinephrine injection is commonly used in emergency situations,it is associated with risks for elderly patients with spasmodic liver pain.This study explores the safety and effectiveness of mebe... BACKGROUND Although norepinephrine injection is commonly used in emergency situations,it is associated with risks for elderly patients with spasmodic liver pain.This study explores the safety and effectiveness of mebendazole injection,an alternative treatment option,for the emergency management of spasmodic abdominal pain,while minimizing adverse reactions,in elderly patients.AIM To explore the development of norepinephrine injection and the adverse reactions of this drug in emergency elderly patients with spasmodic liver pain.METHODS The control group consisted of 56 elderly patients visiting our hospital from January 2021 to December 2021.After hospital admission,the control group was intravenously administered tolopin.The experimental group consisted of 56 emergency patients with spasmodic abdominal pain who visited our hospital until June 2022.After hospital admission,the experimental group was intravenously administered toloxazole.The two groups were treated for 3 d.The disappearance of clinical symptoms was observed before and after the treatment,and the difference in adverse reactions between the two groups was compared.RESULTS The pain of the wife,fire,diarrhea,drowning,and surrounding time disappeared in the experimental group.No statistical difference was observed between the experimental and control groups in visual pain analog scale(VAS)scores before and after the treatment(P>0.05).The VAS scores of abdominal pain severity after 0.5 h,1.0 h,and after 6.0 h of treatment were significantly lower for the experimental group than for the control group.After the treatment,the therapeutic effect in the experimental group was higher and statistically significant than that in the control group(P<0.05).The probability of adverse reactions before the treatment was lower in the experimental group than in the control group.CONCLUSION During emergency,mebendazole injection exhibited a good therapeutic value when used for the clinical treatment of elderly patients with spasmodic stomach pain.It accelerated the disappearance of clinical symptoms such as stomach pain,reduced the stomach weight,and improved clinical activity.Reducing and promoting the frequency of high treatment safety with mebendazole injection is worthwhile. 展开更多
关键词 M-triophenol injection EMERGENCY Spasmodic abdominal pain in the elderly Abdominal pain disappearance time Adverse reactions Therapeutic effect
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跨越280英里与家人团聚的猫
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作者 刘同功 《疯狂英语(新读写)》 2023年第5期31-33,76,共4页
1When De Amicis moved from Ambly⁃sur⁃Meuse,in the Orne region of France,to Ginai in Normandy,with her family a year ago,the family tried to keep their three cats,Felys,Crapaud,and Cocci,in the new house,as they were w... 1When De Amicis moved from Ambly⁃sur⁃Meuse,in the Orne region of France,to Ginai in Normandy,with her family a year ago,the family tried to keep their three cats,Felys,Crapaud,and Cocci,in the new house,as they were worried they'd become lost in their new surroundings.But somehow,Cocci,a sweet gray⁃and⁃white cat,left home and disappeared. 展开更多
关键词 tried WHITE disappear
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Colorectal cancer with liver metastases:Neoadjuvant chemotherapy,surgical resection first or palliation alone? 被引量:22
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作者 Khurum Khan Anita Wale +1 位作者 Gina Brown Ian Chau 《World Journal of Gastroenterology》 SCIE CAS 2014年第35期12391-12406,共16页
Colorectal cancer (CRC) is one of the commonest cancers with 1.2 million new cases diagnosed each year in the world. It remains the fourth most common cause of cancer-related mortality in the world and accounts for &a... Colorectal cancer (CRC) is one of the commonest cancers with 1.2 million new cases diagnosed each year in the world. It remains the fourth most common cause of cancer-related mortality in the world and accounts for &#x0003e; 600000 cancer-related deaths each year. There have been significant advances in treatment of metastatic CRC in last decade or so, due to availability of new active targeted agents and more aggressive approach towards the management of CRC, particularly with liver-only-metastases; however, these drugs work best when combined with conventional chemotherapy agents. Despite these advances, there is a lack of biomarkers to inform us about the accurate management of the patients with metastatic CRC. It is therefore imperative to carefully select the patients with comprehensive multi-disciplinary team input in order to optimise the management of these patients. In this review we will discuss various treatment options available in management of colorectal liver metastases with potential guidance on how and when to choose these options along with consideration on future directions in management of this disease. 展开更多
关键词 Colorectal cancer Colorectal liver metastases Surgical resection Neo-adjuvant chemotherapy Radiofrequency ablation Disappearing liver metastases
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Neoadjuvant chemotherapy for colorectal liver metastases:A contemporary review of the literature 被引量:4
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作者 Marissa Guo Ning Jin +1 位作者 Timothy Pawlik Jordan M Cloyd 《World Journal of Gastrointestinal Oncology》 SCIE 2021年第9期1043-1061,共19页
Colorectal carcinoma(CRC)is one of the leading causes of cancer-related deaths worldwide,and up to 50%of patients with CRC develop colorectal liver metastases(CRLM).For these patients,surgical resection remains the on... Colorectal carcinoma(CRC)is one of the leading causes of cancer-related deaths worldwide,and up to 50%of patients with CRC develop colorectal liver metastases(CRLM).For these patients,surgical resection remains the only opportunity for cure and long-term survival.Over the past few decades,outcomes of patients with metastatic CRC have improved significantly due to advances in systemic therapy,as well as improvements in operative technique and perioperative care.Chemotherapy in the modern era of oxaliplatin-and irinotecancontaining regimens has been augmented by the introduction of targeted biologics and immunotherapeutic agents.The increasing efficacy of contemporary systemic therapies has led to an expansion in the proportion of patients eligible for curative-intent surgery.Consequently,the use of neoadjuvant strategies is becoming progressively more established.For patients with CRLM,the primary advantage of neoadjuvant chemotherapy(NCT)is the potential to down-stage metastatic disease in order to facilitate hepatic resection.On the other hand,the routine use of NCT for patients with resectable metastases remains controversial,especially given the potential risk of inducing chemotherapy-associated liver injury prior to hepatectomy.Current guidelines recommend upfront surgery in patients with initially resectable disease and low operative risk,reserving NCT for patients with borderline resectable or unresectable disease and high operative risk.Patients undergoing NCT require close monitoring for tumor response and conversion of CRLM to resectability.In light of the growing number of treatment options available to patients with metastatic CRC,it is generally agreed that these patients are best served at tertiary centers with an expert multidisciplinary team. 展开更多
关键词 Colorectal liver metastases Neoadjuvant chemotherapy Hepatic resection Conversion therapy Chemotherapy-associated liver injury Disappearing liver metastases Future liver remnant IMMUNOTHERAPY
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Who is in the Lower Reaches,Who Suffers Disasters?——Take Minqin County,a Disappearing Oasis as a Case 被引量:3
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作者 Bao Chao Fang Chuanglin 《Chinese Journal of Population,Resources and Environment》 北大核心 2006年第2期41-46,共6页
Minqin Oasis is located in the lower reaches of the Shiyanghe River Basin, northeast of the Heixi Corridor, at the middle of the Silk Road. Because of the its existence, Badain Jaran Desert and Tengger Desert cannot c... Minqin Oasis is located in the lower reaches of the Shiyanghe River Basin, northeast of the Heixi Corridor, at the middle of the Silk Road. Because of the its existence, Badain Jaran Desert and Tengger Desert cannot converge and develop in the south. It has always been an important green barrier to guarantee the eco-security of Hexi Corridor and the Silk Road for thousands of years. But in recent decades, Minqin Oasis is becoming smaller and the desert is becoming larger. Many people, especially the governmental officials in the lower reaches think that the upper and middle reaches have robbed the lower reaches of water resources, and caused insufficient water usage and the deteriorated eco-environment, in the lower reaches, However, the governmental officials in the upper and middle reaches claim that the whole river basin should take the upper and middle reaches as the key regions to develop economy. To address the above argument, we analyze the reasons why Minqin Oasis is disappearing, and find that there are two main factors. One is the quick development of population and economy in the upper and middle reaches; the other is the rapid development of population and economy in the lower reaches. The two factors both have great effect on the water utilization for eco-environment in the lower reaches. So Minqin Oasis is disappearing not only because of the upper and middle reaches but also because of the growth of population and economy itself. The lower reaches should not completely blame the upper and middle reaches. The upper and middle reaches should also pay more attention to the eco-environment in the lower reaches. The whole river basin should develop a harmonious and sustainable relationship among the upper, middle and lower reaches. 展开更多
关键词 disappearing oasis water dispute spatial optimization Minqin Oasis
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GUIDED CIRCUMFERENTIAL WAVES IN DOUBLE-WALLED CARBON NANOTUBES 被引量:2
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作者 Zhang Huiling Yin Xiaochun 《Acta Mechanica Solida Sinica》 SCIE EI 2007年第2期110-116,共7页
A model of guided circumferential waves propagating in double-walled carbon nanotubes is built by the theory of wave propagation in continuum mechanics, while the van der Waals force between the inner and outer nanotu... A model of guided circumferential waves propagating in double-walled carbon nanotubes is built by the theory of wave propagation in continuum mechanics, while the van der Waals force between the inner and outer nanotube has been taken into account in the model. The dispersion curves of the guided circumferential wave propagation are studied, and some dispersion characteristics are illustrated by comparing with those of single-walled carbon nanotubes. It is found that in double-walled carbon nanotubes, the guided circumferential waves will propagate in more dispersive ways. More interactions between neighboring wave modes may take place. In particular, it has been found that a couple of wave modes may disappear at a certain frequency and that, while a couple of wave modes disappear, another new couple of wave modes are excited at the same wave number. 展开更多
关键词 carbon nanotube guided circumferential waves continuum mechanics van der Waals force dispersion equation mode disappearance and excitation
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DISAPPEARANCE OF INTERFACES FOR DEGENERATE PARABOLIC EQUATIONS WITH VARIABLE DENSITY AND ABSORPTION 被引量:2
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作者 胡学刚 穆春来 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期735-742,共8页
In this article, the authors deal with the Cauchy problem of a nonlinear parabolic equation with variable density and absorption. By using energy methods, the authors prove that the interfaces can disappear in finite ... In this article, the authors deal with the Cauchy problem of a nonlinear parabolic equation with variable density and absorption. By using energy methods, the authors prove that the interfaces can disappear in finite time under some assumptions on the density functions. 展开更多
关键词 Disappearance of interface degenerate parabolic equation variable density absorption
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新课程下的高中英语词汇教学技巧分析 被引量:1
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作者 朱新年 《学子(理论版)》 2016年第10期15-15,共1页
词汇是组成英语语句的基本单元,其直接关乎学生英语学习的整体质量。然而,单纯的英语单词讲授和背诵很容易使学生感觉枯燥、乏味,会逐渐丧失学习的兴趣,甚至会产生厌学的负面情绪,影响课程教学的效果。本文以高中英语词汇教学为研究对象... 词汇是组成英语语句的基本单元,其直接关乎学生英语学习的整体质量。然而,单纯的英语单词讲授和背诵很容易使学生感觉枯燥、乏味,会逐渐丧失学习的兴趣,甚至会产生厌学的负面情绪,影响课程教学的效果。本文以高中英语词汇教学为研究对象,着重就其开展策略进行了探究。一、明确词汇规律,增强记忆效果在现阶段高中英语词汇教学的过程中,很多教师都是让学生通过反复的诵读和背诵来达到记忆单词词汇的目的。 展开更多
关键词 教学情境 负面情绪 学习小组 新课程 情境创设 游戏活动 RECOVER 味感 disappear 专项训练
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CLINICAL OBSERVATIONS ON 278 CASES OF CERVICAL SPONDYLOPATHY TREATED WITH ELECTRO ACUPUNCTURE AND MASSOTHERAPY 被引量:1
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作者 骆仲达 骆竞洪 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 1997年第2期116-118,共3页
From Dec. 1990 to Dec. 1993, 278 cases of cervical spondylopathy were treated with electroacupuncture and massotherapy. The cure rate was 82.7%; but in the control group, it was only 61%, indicating that electroacupun... From Dec. 1990 to Dec. 1993, 278 cases of cervical spondylopathy were treated with electroacupuncture and massotherapy. The cure rate was 82.7%; but in the control group, it was only 61%, indicating that electroacupuncture may enhance the cure rate (P【 0.05). Of the 278 cases treated by three to five sessions, the pain and numbness disappeared in about 96% of the patients. 展开更多
关键词 VERTEBRAL recurrence NEURALGIA SHOULDER CURATIVE severity relieve DISAPPEARANCE ranged eliminated
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Reading Text Under Normal and Disappearing Presentation Conditions 被引量:2
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作者 Simon P. Liversedge 《心理与行为研究》 2004年第3期505-512,共8页
In this article I discuss data from a series of experiments in which readers’ eye movements were recorded as they processed sentences in which each word disappeared or was masked 60ms after fixation onset. We used th... In this article I discuss data from a series of experiments in which readers’ eye movements were recorded as they processed sentences in which each word disappeared or was masked 60ms after fixation onset. We used this paradigm to investigate whether we could induce a gap effect during reading, and how visual and linguistic factors affected eye movements under these conditions. The data showed that no gap effect occurred in our experiment. Overall reading times were the same under normal and disappearing presentation conditions. However, readers did adopt a strategy of making fewer but longer fixations when the text disappeared than when it did not. Additionally, clear frequency effects occurred regardless of whether the text was presented normally or disappeared. This finding indicates that while the visual uptake of information is important, cognitive processes associated with the lexical identification of words are a primary influence on when readers move their eyes during reading. The findings are taken to support the E-Z Reader model of eye movement control. 展开更多
关键词 eye movements disappearing TEXT reading.
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Rapid spontaneous resolution of lumbar ganglion cysts: A case report 被引量:1
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作者 Vito Chiarella Alessandro Ramieri +1 位作者 Marco Giugliano Maurizio Domenicucci 《World Journal of Orthopedics》 2020年第1期68-75,共8页
BACKGROUND To discuss the rare event of spontaneous resolution of a lumbar ganglion cyst,a personal case report and 25 cases culled from the literature were described in detail.We focused on demographic,classification... BACKGROUND To discuss the rare event of spontaneous resolution of a lumbar ganglion cyst,a personal case report and 25 cases culled from the literature were described in detail.We focused on demographic,classification,clinical and radiological findings,treatment,outcome and radiological resolution.CASE SUMMARY A 51-year-old man presented to our observation with complaints of low back and right leg pain.Lumbar magnetic resonance imaging(MRI).showed a L4-L5 ganglion cyst.The patient was referred to medical therapy and bracing.After 4 wk,he showed a complete resolution of pain.The complete spontaneous resolution of the cyst was demonstrated by the followed-up MRI.CONCLUSION Spontaneous resolution of lumbar ganglion is very rare and only 26 cases,including ours,were reported in literature.Different degrees of biomechanical impairment seem to play a fundamental role in the pathogenesis.Related symptoms are essentially represented by low back and/or radicular pain,without significant neurological disorders.Anti-inflammatory drugs,light unloading exercises and brace could be recommended to administrated pain and decrease facet loads.Mean time for clinical improvement was 7 mo,while MRI disappearance occurred in an average time of 11 mo.Therefore,surgery should be applied when conservative treatment,prolonged at least 6 mo,fails. 展开更多
关键词 Lumbar ganglion cyst Spontaneous resolution Conservative treatment Radiological disappearance Case report
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口语中的停顿语 被引量:2
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作者 杜世洪 《语言教育》 1992年第2期28-29,共2页
在与英美人交谈时,我们会留意到很多人都或多或少地使用一些停顿语。他们有的人是由于习惯,而更多的人是由于谈话内容、场景、对象等因素的影响而不得不使用停顿语。常用的停顿语有好几条,现将它们分别介绍如下: 1.Er;erm 说话迟疑不决... 在与英美人交谈时,我们会留意到很多人都或多或少地使用一些停顿语。他们有的人是由于习惯,而更多的人是由于谈话内容、场景、对象等因素的影响而不得不使用停顿语。常用的停顿语有好几条,现将它们分别介绍如下: 1.Er;erm 说话迟疑不决或结巴时,会出现此语。如: “And then he…er…er…just suddenly seemed to…er…disappear.” 展开更多
关键词 英美人 迟疑不决 谈话内容 suddenly disappear MARRIED HAVEN THINK 女口 saying
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Disappearance of unaffected motor cortex activation by repetitive transcranial magnetic stimulation in a patient with cerebral infarct 被引量:1
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作者 Jeong Pyo Seo Sung Ho Jang 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第7期761-762,共2页
The ipsilateral motor pathway from the unaffected motor cortex to the affected extremity is one of the motor recovery mechanisms following stroke (Jang, 2011). Because stroke patients who had shown recovery by this ... The ipsilateral motor pathway from the unaffected motor cortex to the affected extremity is one of the motor recovery mechanisms following stroke (Jang, 2011). Because stroke patients who had shown recovery by this mechanism usually showed poorer motor function, compared with patients who showed recovery by other mechanisms, several researchers have considered this mechanism as a maladaptive plasticity (]ang, 2013). 展开更多
关键词 Disappearance of unaffected motor cortex activation by repetitive transcranial magnetic stimulation in a patient with cerebral infarct MCA
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Wave Interaction with a Partially Reflecting Vertical Wall Protected by a Submerged Porous Bar 被引量:1
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作者 ZHAO Yang LIU Yong LI Huajun 《Journal of Ocean University of China》 SCIE CAS 2016年第4期619-626,共8页
This study gives an analytical solution for wave interaction with a partially reflecting vertical wall protected by a submerged porous bar based on linear potential theory. The whole study domain is divided into multi... This study gives an analytical solution for wave interaction with a partially reflecting vertical wall protected by a submerged porous bar based on linear potential theory. The whole study domain is divided into multiple sub-regions in relation to the structures. The velocity potential in each sub-region is written as a series solution by the separation of variables. A partially reflecting boundary condition is used to describe the partial reflection of a vertical wall. Unknown expansion coefficients in the series solutions are determined by matching velocity potentials among different sub-regions. The analytical solution is verified by an independently developed multi-domain boundary element method(BEM) solution and experimental data. The wave run-up and wave force on the partially reflecting vertical wall are estimated and examined, which can be effectively reduced by the submerged porous bar. The horizontal space between the vertical wall and the submerged porous bar is a key factor, which affects the sheltering function of the porous bar. The wave resonance between the porous bar and the vertical wall may disappear when the vertical wall has a low reflection coefficient. The present analytical solution may be used to determine the optimum parameters of structures at a preliminary engineering design stage. 展开更多
关键词 reflecting submerged preliminary porous partially matching disappear verified carefully satisfy
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Disappearance of Flow as a Function of Impact Parameter for ^(64)Zn+^(58)Ni Collisions at Intermediate Energies 被引量:1
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作者 He Zhi-yong Dai Guang-xi Jin Gen-ming Zhang Feng-shou (Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000)Shen Wen-qing Ma Yu-gang (Institute of Nuclear Research,Chinese Academy of Sciences,Shanghai 201800) 《Chinese journal of nuclear physics》 1994年第4期313-316,共4页
The disappearance of collective flow for <sup>64</sup>Zn+<sup>58</sup>Ni collisions is studied withBUU equation.It is found that the balance energy,E<sub>bal</sub>,is very sensitive... The disappearance of collective flow for <sup>64</sup>Zn+<sup>58</sup>Ni collisions is studied withBUU equation.It is found that the balance energy,E<sub>bal</sub>,is very sensitive to the in-me-dium nucleon-nucleon cross section and increases with the impact parameter. 展开更多
关键词 BUU equation Impact PARAMETER DISAPPEARANCE of FLOW BALANCE energy
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PERSONAL EXPERIENCE ON ACUPUNCTURE TREATMENT OF PERIPHERAL FACIAL PARALYSIS
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《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 1990年第3期176-181,共6页
Xiao Shaoqing 肖少卿(Nanjing College ofTCM)Concerning treatment of facial paraly-sis,in the case of lacrimation from the eye ofthe affected side,deviation of the mouth,flattening or disappearance of the nasolabialgroo... Xiao Shaoqing 肖少卿(Nanjing College ofTCM)Concerning treatment of facial paraly-sis,in the case of lacrimation from the eye ofthe affected side,deviation of the mouth,flattening or disappearance of the nasolabialgroove,the acupoints of Yangming Chan-nels of Hand and Foot should be selected asthe main ones,such as Chengqi(St 1),Sibai(St 2),Yingxiang(LI 20),Dicang(St 4), 展开更多
关键词 deviation FACIAL NANJING minutes 少卿 SHALLOW 透穴法 DISAPPEARANCE instance otherwise
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A review of studies of once-a-month oral contraceptives in China
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作者 孙亦彬 朱蓬弟 《生殖医学杂志》 CAS 1997年第S1期1-10,共10页
关键词 gregation contra disappear ESTROGEN CONTINUATION creased OVARY FIBRIN UTERUS thereafter
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Prosperity and Disappearance of Introduced Fishes in Xiangmoshan Reservoir
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作者 FAN Zhaoting CHEN Weixing LIU Yi FANG Jingjie LIU Qingzhen 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第3期29-37,共9页
In order to enhance the resources, some fishes were introduced into Xiangmoshan reservoir. The introduced fishes consisted of different ecotypes such as silver carp (Hypophthahnichthys rnolitrix (Cuvier et Valencien... In order to enhance the resources, some fishes were introduced into Xiangmoshan reservoir. The introduced fishes consisted of different ecotypes such as silver carp (Hypophthahnichthys rnolitrix (Cuvier et Valenciennes)), big head (Aristichthys nobilis (Richardso)) and lake herring (Coregonus clupeaformis (Mitchill)) that were plankton feeders, common carp (Cyprinus carpio Linnaeus) and crucian carp (Carassius auratus gibelio) belonging to the polyphagia, and also the non-native predator Walleye (Stizostedion vitreum (Mitchill)) and big mouth (Silurus soldatovi rneridonalis Chen), et al. Among there were not only the cool water fish Peled (Coregonus peled (Gmelin)), but also the warm water fish big mouth. The introduction of non-native fishes resulted in ecosystem changes of the reservoir and some native fishes had gone to decrease their population sizes or been in the condition of depopulation such as Opsariichthys uncirostris arnurensis (Berg), Rhodeus sericeus (Pallas) and Silurus asotus (Linnaeus). The native common carp had disappeared after the introduction of non-native species. Roach (Rutilus rutilus lacustris (Pallas) had been thriven for one or two generations after its introduction and immeidiatly disappeared. Silver fish (Protosalanx hyalocranius (Abbott)), Lake herring (Coregonus clupeaformis (Mitchill)) and Walleye (Stizostedion vitreum (Mitchill)) died several years after the introduction, so most of the introduced species has passed out of existence. Via many years introduction of different fishes, composition of species and the structure of the population in the reservoir had been changed obviously. It was necessary to further estimate whether the ecosystem of the reservoir had been damaged. 展开更多
关键词 Xiangmoshan reservoir introdued fish prosperity and disappearance ecological damage
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Nonautonomous solitons in the continuous wave background of the variable-coefficient higher-order nonlinear Schrodinger equation
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作者 戴朝卿 陈未路 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第1期143-146,共4页
We reduce the variable-coefficient higher-order nonlinear Schrodinger equation (VCHNLSE) into the constantcoefficient (CC) one. Based on the reduction transformation and solutions of CCHNLSE, we obtain analytical ... We reduce the variable-coefficient higher-order nonlinear Schrodinger equation (VCHNLSE) into the constantcoefficient (CC) one. Based on the reduction transformation and solutions of CCHNLSE, we obtain analytical soliton solutions embedded in the continuous wave background for the VCHNLSE. Then the excitation in advancement and sustainment of soliton arrays, and postponed disappearance and sustainment of the bright soliton embedded in the background are discussed in an exponential system. 展开更多
关键词 higher-order nonlinear Schrodinger equation soliton solution continuous wave background postponed disappearance and sustainment of soliton
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