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Machine learning model for prediction of low anterior resection syndrome following laparoscopic anterior resection of rectal cancer:A multicenter study 被引量:1
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作者 Zhang Wang Sheng-Li Shao +3 位作者 Lu Liu Qi-Yi Lu Lei Mu Ji-Chao Qin 《World Journal of Gastroenterology》 SCIE CAS 2023年第19期2979-2991,共13页
BACKGROUND Low anterior resection syndrome(LARS)severely impairs patient postoperative quality of life,especially major LARS.However,there are few tools that can accurately predict major LARS in clinical practice.AIM ... BACKGROUND Low anterior resection syndrome(LARS)severely impairs patient postoperative quality of life,especially major LARS.However,there are few tools that can accurately predict major LARS in clinical practice.AIM To develop a machine learning model using preoperative and intraoperative factors for predicting major LARS following laparoscopic surgery of rectal cancer in Chinese populations.METHODS Clinical data and follow-up information of patients who received laparoscopic anterior resection for rectal cancer from two medical centers(one discovery cohort and one external validation cohort)were included in this retrospective study.For the discovery cohort,the machine learning prediction algorithms were developed and internally validated.In the external validation cohort,we evaluated the trained model using various performance metrics.Further,the clinical utility of the model was tested by decision curve analysis.RESULTS Overall,1651 patients were included in the present study.Anastomotic height,neoadjuvant therapy,diverting stoma,body mass index,clinical stage,specimen length,tumor size,and age were the risk factors associated with major LARS.They were used to construct the machine learning model to predict major LARS.The trained random forest(RF)model performed with an area under the curve of 0.852 and a sensitivity of 0.795(95%CI:0.681-0.877),a specificity of 0.758(95%CI:0.671-0.828),and Brier score of 0.166 in the external validation set.Compared to the previous preoperative LARS score model,the current model exhibited superior predictive performance in predicting major LARS in our cohort(accuracy of 0.772 for the RF model vs 0.355 for the preoperative LARS score model).CONCLUSION We developed and validated a robust tool for predicting major LARS.This model could potentially be used in the clinic to identify patients with a high risk of developing major LARS and then improve the quality of life. 展开更多
关键词 Machine learning Low anterior resection syndrome Rectal cancer LAPAROSCOPY PREDICTION
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Time and Dose-related Effects of the Pyrethroid Fluvalinate on Haemolymph Carbohydrates and Gut Lipids of Honeybees,Following in vivo Injection of very Low Doses 被引量:1
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作者 K.M'DIAYE M.BOUNIAS 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1993年第2期145-153,共9页
The injection to emerging adult workerbees with fluvalinate doses ranging from 1 femtomol to 1 nanomol per individual resulted in a reduction of haemolymph carbohydrate concentrations, particularly at the lowest dose ... The injection to emerging adult workerbees with fluvalinate doses ranging from 1 femtomol to 1 nanomol per individual resulted in a reduction of haemolymph carbohydrate concentrations, particularly at the lowest dose 1 hour after injections. At the same time, a large increase was observed for triacylglycerols and to a much lesser extent for steroids and phospholipids with 0.1 picomol per bee. By contrast, fatty acids, steroids and triacylglycerols exhibited a depress at the higher dose. Most responses were thus biphasic, showing that much attention should be paid to the effects of very low doses of pesticide. 展开更多
关键词 Time and Dose-related Effects of the Pyrethroid Fluvalinate on Haemolymph Carbohydrates and Gut Lipids of Honeybees Following in vivo Injection of very Low Doses very
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Changes in Lymphocyte Reactivity to ModulatoryFactors Following Low DoseIonizing Radiation
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作者 LIUShu-Zheng HANZhen-Bo 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1994年第2期130-135,共6页
Catecholamines (CA) and corticosterone (CS) exerted modulatory effect on the proliferative activity of splenic and thymic lymphocytes in response to mitogenic stimulation in vilro. Epinephrine (E) and norepinephrine (... Catecholamines (CA) and corticosterone (CS) exerted modulatory effect on the proliferative activity of splenic and thymic lymphocytes in response to mitogenic stimulation in vilro. Epinephrine (E) and norepinephrine (NE) potentiated proliferation in concentrations above 1 and 10 nmol/L, respectively, while CS showed a biphasic effect, stimulating proliferation at concentrations below 0.1 nmol/L and suppressing proliferation at concentrations above 10 nmol/L. Combination of CS with E, NE or both in an ineffective concentration of each (0.1 nmol/L ) showed stimulatory effect on the proliferative response of both splenic and thymic lympliocytes to Con A. Whole-body irradiation (WBI) of mice with 75 mGy incIeased the reactivity of splenic and thymic lymphocytes to Con A. It is reported for the first time in the present paper that the proliferative reactivity of splenic and thymic lymphocytes from low dose irradiated mice could be further increased in the presence of suboptimal concentrations of CS and E as well as suboptimal concentrations of phorbol myristate acetate (PMA ) and A23187. These findings may have significance in the mechanism of immunologic stimulation after low dose WBI 展开更多
关键词 Zhang Changes in Lymphocyte Reactivity to ModulatoryFactors Following Low DoseIonizing Radiation
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Effect of long-term low dose of aspirin on severity of disease following onset of acute cerebral infarction
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作者 Jun Xu Lili Cao Xiaomei Deng Enji Han 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第1期67-69,共3页
BACKGROUND: Aspirin can decrease the incidence risk of high-risk crowdgroup of cerebral infarction, but there are still controversy if it might decrease the degree of disease in degree of patients with acute cerebral... BACKGROUND: Aspirin can decrease the incidence risk of high-risk crowdgroup of cerebral infarction, but there are still controversy if it might decrease the degree of disease in degree of patients with acute cerebral infarction. OBJECTIVE: To observe the effect of lower dose of aspirin during taking for a long time on disease degree of disease following onset of acute cerebral infarction. DESIGN: Grouping according to the admission time and 1:1 paired observation.SETTING : Department of Neurology, Qilu Hospital of Shandong University.PARTICIPANTS : The participants in present study were 321 patients with acute cerebral infarction who received treatments in the Department of Neurology, Qilu Hospital of Shandong University from January 1999 to June 2000. There were 190 male and 131 female ,with mean (65±11 )years of age. Inclusive criteria: ① A focal neurological disturbance occurred suddenly and had lasted for more than 24 hours, patients were admitted within 3 days after onset of disease; ② A computed tomography of the brain was performed and excluded hemorrhage in all patients; ③ The patients were proved internal carotid occlusions by clinical features and image findings; ④ The functions of limbs were normal (before the first stroke) or almost normal (before the second stroke). Exclusive criteria:①The patients who had have cardiogenic cerebral embolism; ②The patients who had taken warfarin orally and other platelet agglutination drugs. METHODS :①All the patients were divided into 2 groups according to whether they had taken aspirin before: aspirin-treated group (n=110) and blank control group (n=211). there were 70 male and 40 female in aspirin-treated group, with average(65±10) years of age.All patients had taken 50-100 mg/d aspirin for 6 months to 10 years before onset. There were 120 male and 91 female in blank control group, with average (65±13) years of age. Patients received a clinical scoring within 3 days and similar therapeutic measures (such as anti-platelet agglutination, improving cerebral circulation and metabolism-promoting reagent). Two groups of patients had the same basic conditions except for taking aspirin or not before. ②The matched pairs were made between 50 cases selected from aspirin-treated group and 50 cases from non-aspirin-treated groups according to age, gender, and other stroke risk factors. ③ Evaluation: Degree of disease after onset was evaluated by means of Acute Cerebral Infarction Clinical Neurologic Impairment Degree Scoring Standard of Carotid Artery System. MAIN OUTCOME MEASURES: Acute Cerebral Infarction Clinical Neurologic Impairment Degree Scoring Standard of Carotid Artery System. RESULTS : All 321 patients entered the stage of analysis with no loss in the midway. ① The symptom following onset of acute cerebral infarction was evaluated with clinical neurologic impairment scoring criteria, there were no significant differences between aspirin group and blank control group [(17.39±9.90) vs (16.22 ± 9.98) (t=1.025, P〉 0.05)]. ② No significant differences were found in 1:1 matched pairs of 100 cases from aspirin group and blank control group (t=1.74, P 〉 0.05). CONCLUSION : Taking a lower dose of aspirin during long time may not decrease the degree of disease following onset of acute cerebral infarction. 展开更多
关键词 Effect of long-term low dose of aspirin on severity of disease following onset of acute cerebral infarction
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Interannual Relationship between the Winter Aleutian Low and Rainfall in the Following Summer in South China 被引量:1
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作者 SONG Lin-Ye DUAN Wan-Suo 《Atmospheric and Oceanic Science Letters》 CSCD 2015年第5期271-276,共6页
Using observations and reanalysis data, this study investigates the interannual relationship between the winter Aleutian Low(AL) and the rainfall anomalies in the following summer in South China(SC). Results show that... Using observations and reanalysis data, this study investigates the interannual relationship between the winter Aleutian Low(AL) and the rainfall anomalies in the following summer in South China(SC). Results show that the winter AL is significantly positively(negatively) correlated with the SC rainfall anomalies in the following July(August). Specifically, SC rainfall anomalies have a tendency to be positive(negative) in July(August) when the preceding winter AL is stronger than normal. The winter AL-related atmospheric circulation anomalies in the following summer are also examined. When the winter AL is stronger, there is a significant anticyclonic(cyclonic) circulation anomaly over the subtropical western North Pacific in the following July(August). Southerly(northerly) wind anomalies to the west of this anomalous anticyclonic(cyclonic) circulation increase(decrease) the northward moisture transportation and contribute to the positive(negative) rainfall anomalies over SC in July(August). This study indicates that the AL in the preceding winter can be used as a potential predictor of the rainfall anomalies in the following July and August over SC. 展开更多
关键词 Aleutian Low SOUTH China RAINFALL atmospheric circ
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Astrocytic effect of low molecular weight heparin-superoxide dismutase conjugate in interleukin-6 overexpressing mice following local cerebral ischemia 被引量:1
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作者 Yizhao Li Guixiang Cui +4 位作者 Qingde Wang Hongxia Liu Xiaoxia Zhang Fengshan Wang Keqin Xie 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第2期148-151,共4页
BACKGROUND: Studies have shown that low molecular weight heparin-superoxide dismutase conjugate exhibits a remarkable neuroprotective effect. OBJECTIVE: To investigate the effect of low molecular weight heparin-supe... BACKGROUND: Studies have shown that low molecular weight heparin-superoxide dismutase conjugate exhibits a remarkable neuroprotective effect. OBJECTIVE: To investigate the effect of low molecular weight heparin-superoxide dismutase conjugate on astrocytes in an interleukin-6 (IL-6) overexpressing mice following local cerebral ischemia. DESIGN, TIME AND SETTING: Randomized, cytological, controlled, animal study was performed in the Department of Physiology and Neuroscience, Neurology and Biochemistry and Molecular Biology, Medical University of South Carolina from January 2005 to March 2005. MATERIALS: Nine IL-6 transgenic mice, irrespective of gender, were randomly divided into three groups: sham-operated, model, and treatment, with three mice in each group. With exception of the sham-operated group, right middle cerebral artery occlusion was induced in the mice. Expression of glial fibrillary acidic protein, an astrocyte marker, was determined by immunohistochemistry. Low molecular weight heparin-superoxide dismutase conjugate was purchased from Biochemistry and Biotechnique Institute, Shandong University. METHODS: Two minutes prior to ischemia induction, 0.5 mL/kg saline or 20 000 U/kg low molecular weight heparin-superoxide dismutase conjugate were administrated via the femoral artery in the model group and treatment group, respectively. The sham-operated group underwent the same protocols, with the exception of occlusion and treatment. MAIN OUTCOME MEASURES: The number of glial fibrillary acidic protein-positive cells was quantified under light microscopy (x200). RESULTS: In the sham-operated group, there were a large number of astrocytes in the IL-6 transgenic mice. However, the cell bodies were small, and the branches were few and thin. The number of astrocytes in the model group was remarkably less than the sham-operated group. Compared to the model and sham-operated groups, the number of astrocytes significantly increased, and the cell body became larger, following treatment with low molecular weight heparin-superoxide dismutase conjugate. Astrocytes exhibited hypertrophy and hyperplasia, and the processes became longer and thicker. CONCLUSION: The low molecular weight heparin-superoxide dismutase conjugate may provide neuroprotection through astrocytic activation at the super-early stage of cerebral ischemia and reperfusion. 展开更多
关键词 cerebral ischemia ASTROCYTES low molecular weight heparin-superoxide dismutase conjugate
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Improvement in Radicular Symptoms but Continued Facet Arthropathy and Axial Back Pain Following Rupture of a Facet Joint Synovial Cyst 被引量:1
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作者 Bryan J. Kratz Troy Buck Daniel Cramer 《Neuroscience & Medicine》 2018年第1期46-52,共7页
Lumbar synovial cysts are benign fluid collections thought to form in a background of facet joint degeneration, allowing for fluid to leak from the joint capsule and form cysts in the synovium. Although often asymptom... Lumbar synovial cysts are benign fluid collections thought to form in a background of facet joint degeneration, allowing for fluid to leak from the joint capsule and form cysts in the synovium. Although often asymptomatic, patients with symptomatic synovial cysts will present with low back pain and possibly an associated radiculopathy. Clinicians can consider conservative management, epidural steroid injection, surgical intervention, or facet joint block with aspiration and rupture. This case describes a 59-year-old male facilities manager with intermittent low back pain for one year with worsening right-sided radicular symptoms secondary to a lumbar facet joint synovial cyst in the context of severe facet arthropathy and microinstability. The patient’s low back pain and radicular symptoms were refractory to conservative treatment. Imaging demonstrated a lumbar synovial cyst and subsequent management included transforaminal epidural steroid injection and facet joint block with cyst aspiration and rupture. The patient’s radicular pain resolved but axial lumbar pain returned after 3 weeks of relief. Follow-up imaging demonstrated decreased cyst size with fluid accumulation and joint space widening. Although the cyst was successfully decompressed with resolution of radicular pain, the underlying facet arthropathy remains contributing to persistent axial low back pain and potential for continued degenerative changes including cyst recurrence. 展开更多
关键词 FACET Joint SYNOVIAL CYST Lumbar SYNOVIAL CYST Radicular PAIN CYST RUPTURE Low Back PAIN Non-Surgical Management
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Compensatory Growth of Juvenile Brown Flounder Paralichthys olivaceus Following Low Temperature Treatment for Different Periods
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作者 PENG Yinhui LIU Xiujia +2 位作者 HUANG Guoqiang WEI Liuzhi ZHANG Xiumei 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第2期326-332,共7页
We investigated the effects of low temperature(8.5℃) on the growth and feeding rates and feed conversion efficiency of juvenile P.olivaceus with an average initial weight of 3.87 ± 0.06 g(mean ± SE).Fish we... We investigated the effects of low temperature(8.5℃) on the growth and feeding rates and feed conversion efficiency of juvenile P.olivaceus with an average initial weight of 3.87 ± 0.06 g(mean ± SE).Fish were exposed to 8.5℃ for 0(control),1,2,3 and 4 weeks,and then to 20℃ for 10,9,8,7 and 6 weeks,respectively.Low temperature clearly led to growth depression.The weight of fish exposed to low temperature for 1 week was restored to that of control,while that of fish exposed to low temperature longer was significantly decreased(P < 0.05).During the entire low-temperature period,specific growth rate,feeding rate and feed conversion efficiency of the fish were significantly lower(P < 0.05) than those of control,while in the whole recovery period,specific growth and average feeding rate were markedly higher(P < 0.05) than those of control.At the end of experiment,only the feeding rate of the fish exposed to low temperature for 1 week was not significantly different from that of control(P > 0.05).Feeding rate and feed conversion efficiency were reduced at low temperature in juvenile P.olivaceus.The compensatory growth of juvenile P.olivaceus may therefore be attributed to the improvement of feeding rate.Our results suggested that growth depression occurs when juvenile P.olivaceus are exposed to low temperature for more than one week. 展开更多
关键词 PARALICHTHYS OLIVACEUS COMPENSATORY growth low temperature exposure feeding rate
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Post traumatic dural sinus thrombosis following epidural hematoma: Literature review and case report
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作者 Lorenzo Pescatori Maria Pia Tropeano +3 位作者 Cristina Mancarella Emiliano Prizio Giorgio Santoro Maurizio Domenicucci 《World Journal of Clinical Cases》 SCIE 2017年第7期292-298,共7页
Dural sinus thrombosis following a head trauma is a rare condition,described in literature along with the lack of consensus regarding diagnosis and management.We present a case of a fifty-year-old man with a head inju... Dural sinus thrombosis following a head trauma is a rare condition,described in literature along with the lack of consensus regarding diagnosis and management.We present a case of a fifty-year-old man with a head injury and combined supratentorial-subtentorial epidural hematoma who was treated conservatively through the administration of low molecular weight heparin.The diagnosis and management of this condition are discussed based on a literature review.The early diagnosis may prevent potentially treatable poor outcomes. 展开更多
关键词 DURAL SINUS THROMBOSIS EPIDURAL HEMATOMA Low molecular weight HEPARIN
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Finding the Needle in the Haystack—An Unusual Case of Astasia-Abasia Following Sacro-Iliac Joint Injection for Chronic Low Back Pain
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作者 Gurmukh Das Punshi Andrew Purcell Camillus Power 《Pain Studies and Treatment》 2021年第1期1-6,共6页
We present the case of a 60 yrs old male who, following a routine, uneventful, fluoroscopically guided L5/S1 facet joint rhizolysis and sacro-iliac joint (SIJ) injection developed an unexpected inability to stand or w... We present the case of a 60 yrs old male who, following a routine, uneventful, fluoroscopically guided L5/S1 facet joint rhizolysis and sacro-iliac joint (SIJ) injection developed an unexpected inability to stand or walk, a condition known as astasia-abasia. Initial concern had been that this neurological phenomenon was as a result of complications of his chronic pain intervention. Despite an essentially normal neurological examination and dedicated battery of neurological imaging and special testing, no cause was identified. Over a 7-day period of in-patient admission and physical rehabilitation symptoms resolved entirely. In the course of the workup for this episode, it was suggested that the phenomenon was the result of a side effect of dexamfetamine, an agent that had been prescribed for the patient by his neurologist for treatment of his narcolepsy. On the back of this episode, this treatment was discontinued by his neurologist following an outpatient consultation. Subsequent repeated SIJ injections were entirely uneventful and the patient experienced no further occurrences of this phenomenon. 展开更多
关键词 Chronic Low Back Pain Sacroiliac Joint Injection Dexamfetamine Astasia-Abasia
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Transanal minimally invasive surgery to rescue anastomosis following leak after low anterior resection: A case report
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作者 James Wei Tatt Toh Henry Wang +5 位作者 Geoffrey Collins Chelsea Beinke Elissa Zhang Alistair Escott Toufic El-Khoury Nimalan Pathma-Nathan 《Laparoscopic, Endoscopic and Robotic Surgery》 2021年第4期121-124,共4页
Restorative low anterior resection(LAR)for rectal cancer carries a significant risk of anastomotic leak:One of the most feared complications in colorectal surgery.Operative management may include takedown of the anast... Restorative low anterior resection(LAR)for rectal cancer carries a significant risk of anastomotic leak:One of the most feared complications in colorectal surgery.Operative management may include takedown of the anastomosis and end colostomy which,in some cases,is permanent.Other contemporary operative measures include over the scope clips and Endosponge.Recently,there have been case reports and a Society of American Endoscopic and Gastrointestinal Surgeons video on the novel use of transanal minimally invasive surgery(TAMIS)in the management of anastomotic leak.We present a 59-year-old female who underwent LAR after declining radiotherapy for a bulky 9 cm rectal tumour 9-10 cm from the anal verge.Following clinical deterioration,computed tomography demonstrated an anastomotic leak communicating with a 5-cm pelvic collection containing gas.At laparoscopy,pus and faeculent material were washed from the pelvic cavity and drains were placed.Intra-operative endoscopy demonstrated a 7-8 mm dehiscence at the anastomosis.The defect(approximately 7 cm from the anal verge)was successfully closed using TAMIS and a running V-lock suture.The patient recovered well and was discharged home on post-operative day 20.In this case,a low colorectal anastomotic leak was successfully rescued with TAMIS.This novel technique may be useful in the armamentarium of colorectal surgeons experienced in TAMIS. 展开更多
关键词 Transanal minimally invasive surgery Anastomotic leak Low anterior resection Colorectal cancer
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低温等离子治疗儿童鼻咽部第二鳃裂囊肿分析
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作者 温鑫 黄爱萍 +5 位作者 张爱英 许敏 宋英鸾 崔莉 耿江桥 史静 《中国耳鼻咽喉头颈外科》 CSCD 2024年第1期54-56,共3页
目的探讨儿童鼻咽部第二鳃裂囊肿的临床特征和治疗方式,提高诊治能力。方法回顾性分析河北省儿童医院收治的4例儿童鼻咽部第二鳃裂囊肿的临床资料,包括年龄、性别、症状、影像学资料和治疗过程。总结分析病变部位特点,B超、CT或MRI特征... 目的探讨儿童鼻咽部第二鳃裂囊肿的临床特征和治疗方式,提高诊治能力。方法回顾性分析河北省儿童医院收治的4例儿童鼻咽部第二鳃裂囊肿的临床资料,包括年龄、性别、症状、影像学资料和治疗过程。总结分析病变部位特点,B超、CT或MRI特征,术后病理结果及治疗方式。结果4例鼻咽部第二鳃裂囊肿患儿均表现为鼻咽侧壁咽鼓管咽口与腭咽弓后上方连线上的囊性肿物,囊壁较厚,影像学检查结果均为囊性病变。4例患儿选择内镜下低温等离子病变切除术,其中2例为内侧囊壁大部分切除术,将囊腔充分敞开,2例为囊肿全部切除术。术后病理提示衬覆纤毛柱状上皮或复层上皮,周围淋巴组织增生。术后随访1.5~3年无复发。结论儿童鼻咽部第二鳃裂囊肿临床罕见,诊断主要依靠病变部位及术后病理结果,内镜下低温等离子切除病变组织是微创、安全、有效的治疗方式。 展开更多
关键词 儿童(Child) 外科手术(Surgical Procedures Operative) 鼻咽部第二鳃裂囊肿(nasopharyngeal cyst of second branchial cleft) 低温等离子(low temperature plasma)
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Application of artificial hibernation technology in acute brain injury 被引量:1
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作者 Xiaoni Wang Shulian Chen +5 位作者 Xiaoyu Wang Zhen Song Ziqi Wang Xiaofei Niu Xiaochu Chen Xuyi Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期1940-1946,共7页
Controlling intracranial pressure,nerve cell regeneration,and microenvironment regulation are the key issues in reducing mortality and disability in acute brain injury.There is currently a lack of effective treatment ... Controlling intracranial pressure,nerve cell regeneration,and microenvironment regulation are the key issues in reducing mortality and disability in acute brain injury.There is currently a lack of effective treatment methods.Hibernation has the characteristics of low temperature,low metabolism,and hibernation rhythm,as well as protective effects on the nervous,cardiovascular,and motor systems.Artificial hibernation technology is a new technology that can effectively treat acute brain injury by altering the body’s metabolism,lowering the body’s core temperature,and allowing the body to enter a state similar to hibernation.This review introduces artificial hibernation technology,including mild hypothermia treatment technology,central nervous system regulation technology,and artificial hibernation-inducer technology.Upon summarizing the relevant research on artificial hibernation technology in acute brain injury,the research results show that artificial hibernation technology has neuroprotective,anti-inflammatory,and oxidative stress-resistance effects,indicating that it has therapeutic significance in acute brain injury.Furthermore,artificial hibernation technology can alleviate the damage of ischemic stroke,traumatic brain injury,cerebral hemorrhage,cerebral infarction,and other diseases,providing new strategies for treating acute brain injury.However,artificial hibernation technology is currently in its infancy and has some complications,such as electrolyte imbalance and coagulation disorders,which limit its use.Further research is needed for its clinical application. 展开更多
关键词 cute brain injury artificial hibernation HYPOTHERMIA low metabolism mild hypothermia
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An NMOS output-capacitorless low-dropout regulator with dynamic-strength event-driven charge pump 被引量:1
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作者 Yiling Xie Baochuang Wang +1 位作者 Dihu Chen Jianping Guo 《Journal of Semiconductors》 EI CAS CSCD 2024年第6期23-34,共12页
In this paper,an NMOS output-capacitorless low-dropout regulator(OCL-LDO)featuring dual-loop regulation has been proposed,achieving fast transient response with low power consumption.An event-driven charge pump(CP)loo... In this paper,an NMOS output-capacitorless low-dropout regulator(OCL-LDO)featuring dual-loop regulation has been proposed,achieving fast transient response with low power consumption.An event-driven charge pump(CP)loop with the dynamic strength control(DSC),is proposed in this paper,which overcomes trade-offs inherent in conventional structures.The presented design addresses and resolves the large signal stability issue,which has been previously overlooked in the event-driven charge pump structure.This breakthrough allows for the full exploitation of the charge-pump structure's poten-tial,particularly in enhancing transient recovery.Moreover,a dynamic error amplifier is utilized to attain precise regulation of the steady-state output voltage,leading to favorable static characteristics.A prototype chip has been fabricated in 65 nm CMOS technology.The measurement results show that the proposed OCL-LDO achieves a 410 nA low quiescent current(IQ)and can recover within 30 ns under 200 mA/10 ns loading change. 展开更多
关键词 output-capacitorless low-dropout regulator fast transient low quiescent current event-driven charge pump
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Novel approach of ultrasound-guided lateral recess block for a patient with lateral recess stenosis: A case report 被引量:1
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作者 Jiao Yang Xin-Ling Li Qing-Bing Li 《World Journal of Clinical Cases》 SCIE 2024年第5期1010-1017,共8页
BACKGROUND Ultrasound guide technology,which can provide real-time visualization of the needle tip and tissues and avoid many adverse events,is widely used in mini-mally invasive therapy.However,the studies on ultraso... BACKGROUND Ultrasound guide technology,which can provide real-time visualization of the needle tip and tissues and avoid many adverse events,is widely used in mini-mally invasive therapy.However,the studies on ultrasound-guided Lateral recess block(LRB)are limited,this is probably because there is no recognized standard method for ultrasound scanning.This study aimed to evaluate the effect of ultrasound-guided LRB in patients with lateral recess stenosis(LRS).CASE SUMMARY A 65-year-old patient complained of low back pain accompanied occasionally by pain and numbness in the left lower limb.Physical examination showed ten-derness on the spinous process and paraspinal muscles from L1 to S1,extensor hallucis longus and tibialis anterior weakness(muscle strength:4-),and a positive straight leg raising test in the left lower limb(60°).Magnetic resonance imaging showed L4–L5 disc degeneration with left LRS and nerve root entrapment.Subsequently,the patient was diagnosed with LRS.This patient was treated with a novel ultrasound-guided LRB approach.The patient’s symptoms significantly improved without any complications at 1 wk postoperatively and at the 3-month follow-up.CONCLUSION This is the first report on the LRS treatment with ultrasound-guided LRB from the contralateral spinous process along the inner side of the articular process by out-plane technique.Further studies are expected to investigate the efficacy and safety of ultrasound-guided LRB for patients with LRS. 展开更多
关键词 Lateral recess stenosis ULTRASOUND Lateral recess block Real-time visualization Low back pain Case report
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Alkyl dimethyl betaine activates the low-temperature collection capacity of sodium oleate for scheelite
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作者 Xu Wang Zhengquan Zhang +5 位作者 Yanfang Cui Wei Li Congren Yang Hao Song Wenqing Qin Fen Jiao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期71-80,共10页
The impact of alkyl dimethyl betaine (ADB) on the collection capacity of sodium oleate (NaOl) at low temperatures was evaluated using flotation tests at various scales. The low-temperature synergistic mechanism of ADB... The impact of alkyl dimethyl betaine (ADB) on the collection capacity of sodium oleate (NaOl) at low temperatures was evaluated using flotation tests at various scales. The low-temperature synergistic mechanism of ADB and NaOl was explored by infrared spectroscopy, X-ray photoelectron spectroscopy, surface tension measurement, foam performance test, and flotation reagent size measurement.The flotation tests revealed that the collector mixed with octadecyl dimethyl betaine (ODB) and NaOl in a mass ratio of 4:96 exhibited the highest collection capacity. The combined collector could increase the scheelite recovery by 3.48% at low temperatures of 8–12℃. This is particularly relevant in the Luanchuan area, which has the largest scheelite concentrate output in China. The results confirmed that ODB enhanced the collection capability of NaOl by improving the dispersion and foaming performance. Betaine can be introduced as an additive to NaOl to improve the recovery of scheelite at low temperatures. 展开更多
关键词 SCHEELITE BETAINE low temperature synergistic effect dispersion FOAMABILITY
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Enhancing fatigue performance of AZ31 magnesium alloy components fabricated by cold metal transfer-based wire arc directed energy deposition through LPB
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作者 Shambhu Kumar Manjhi Srikanth Bontha A.S.S.Balan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1638-1662,共25页
Cold Metal Transfer-Based Wire Arc Directed Energy Deposition(CMT-WA-DED)presents a promising avenue for the rapid fabrication of components crucial to automotive,shipbuilding,and aerospace industries.However,the susc... Cold Metal Transfer-Based Wire Arc Directed Energy Deposition(CMT-WA-DED)presents a promising avenue for the rapid fabrication of components crucial to automotive,shipbuilding,and aerospace industries.However,the susceptibility to fatigue of CMT-WA-DED-produced AZ31 Mg alloy components has impeded their widespread adoption for critical load-bearing applications.In this study,a comprehensive investigation into the fatigue behaviour of WA-DED-fabricated AZ31 Mg alloy has been carried out and compared to commercially available wrought AZ31 alloy.Our findings indicate that the as-deposited parts exhibit a lower fatigue life than wrought Mg alloy,primarily due to poor surface finish,tensile residual stress,porosity,and coarse grain microstructure inherent in the WA-DED process.Low Plasticity Burnishing(LPB)treatment is applied to mitigate these issues,which induce significant plastic deformation on the surface.This treatment resulted in a remarkable improvement of fatigue life by 42%,accompanied by a reduction in surface roughness,grain refinement and enhancement of compressive residual stress levels.Furthermore,during cyclic deformation,WA-DED specimens exhibited higher plasticity and dislocation density compared to both wrought and WA-DED+LPB specimens.A higher fraction of Low Angle Grain Boundaries(LAGBs)in WA-DED specimens contributed to multiple crack initiation sites and convoluted crack paths,ultimately leading to premature failure.In contrast,wrought and WA-DED+LPB specimens displayed a higher percentage of High Angle Grain Boundaries(HAGBs),which hindered dislocation movement and resulted in fewer crack initiation sites and less complex crack paths,thereby extending fatigue life.These findings underscore the effectiveness of LPB as a post-processing technique to enhance the fatigue performance of WA-DED-fabricated AZ31 Mg alloy components.Our study highlights the importance of LPB surface treatment on AZ31 Mg components produced by CMT-WA-DED to remove surface defects,enabling their widespread use in load-bearing applications. 展开更多
关键词 Wire arc additive manufacturing AZ31 Mg alloy Low plasticity burnishing Low cycle fatigue test Strain amplitude
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An effective'salt in dimethyl sulfoxide/water'electrolyte enables high-voltage supercapacitor operated at-50℃
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作者 Yingbin Liu Chang Yu +5 位作者 Xuedan Song Siyi Hou Shuqin Lan Jinhe Yu Yuanyang Xie Jieshan Qiu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期361-367,I0009,共8页
Compared with organic electrolytes,aqueous electrolytes exhibit significantly higher ionic conductivity and possess inherent safety features,showcasing unique advantages in supercapacitors.However,challenges remain fo... Compared with organic electrolytes,aqueous electrolytes exhibit significantly higher ionic conductivity and possess inherent safety features,showcasing unique advantages in supercapacitors.However,challenges remain for low-salt aqueous electrolytes operating at high voltage and low temperature.Herein,we report a low-salt(0.87 m,m means mol kg^(-1))'salt in dimethyl sulfoxide/water'hybrid electrolyte with non-flammability via hybridizing aqueous electrolyte with an organic co-solvent of dimethyl sulfoxide(hydrogen bond acceptor).As a result,the 0.87 m hybrid electrolyte exhibits enhanced electrochemical stability,a freezing temperature below-50℃,and an outstanding ionic conductivity of 0.52mS cm~(-1)at-50℃.Dimethyl sulfoxide can anchor water molecules through intermolecular hydrogen bond interaction,effectively reinforcing the stability of water in the hybrid electrolyte.Furthermore,the interaction between dimethyl sulfoxide and water molecules diminishes the involvement of water in the generation of ordered ice crystals,finally facilitating the low-temperature performance of the hybrid electrolyte.When paired with the 0.87 m'salt in dimethyl sulfoxide/water'hybrid electrolyte,the symmetric supercapacitor presents a 2.0 V high operating voltage at 25℃,and can operate stably at-50℃.Importantly,the suppressed electrochemical reaction of water at-50℃further leads to the symmetric supercapacitor operated at a higher voltage of 2.6 V.This modification strategy opens an effective avenue to develop low-salt electrolytes for high-voltage and low-temperature aqueous supercapacitors. 展开更多
关键词 Dimethyl sulfoxide CO-SOLVENT High voltage Low temperature SUPERCAPACITORS
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Simultaneous removal of sulfur dioxide and nitrogen oxide from flue gas by phosphorus sludge:The performance and absorption mechanism
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作者 Yuanyuan Yin Xujun Wang +3 位作者 Lei Xu Binbin He Yunxiang Nie Yi Mei 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期212-221,共10页
Developing low-cost and green simultaneous desulfurization and denitrification technologies is of great significance for sulfur dioxide(SO_(2))and nitrogen oxide(NO_(x))emission control at low temperatures,especially ... Developing low-cost and green simultaneous desulfurization and denitrification technologies is of great significance for sulfur dioxide(SO_(2))and nitrogen oxide(NO_(x))emission control at low temperatures,especially for small and medium-sized coal-fired boilers and furnaces.Herein,phosphorus sludge,an industrial waste from the production process of yellow phosphorus,has been developed to simultaneously eliminate SO_(2)and NO_(x)from coal-fired flue gas.The key factors affecting the experimental results indicate that desulfurization and denitrification efficiency of over 95%can be achieved at a low temperature of 55℃.Further,the absorption mechanism was investigated by characterizing the solid and liquid phases of the phosphorus sludge during the absorption process.The efficient removal of SO_(2)is attributed to the abundance of iron(Fe^(3+))and manganese(Mn^(2+))in the absorbent.SO_(2)can be rapidly catalyzed and converted to SO_(4)^(2-)by them.The key to NOx removal is the oxidation of NO toward watersoluble high-valent nitrogen oxides by oxidizing reactive substances induced via yellow phosphorus,which are then absorbed by water and converted to NO_(3)^(-).Meanwhile,yellow phosphorus is oxidized to phosphoric acid(H_(3)PO_(4)).The spent absorption slurry can be reused through wet process phosphoric acid production,as it contains sulfuric acid(H_(2)SO_(4)),nitric acid(HNO_(3)),and H_(3)PO_(4).Accordingly,this is a technology with broad application prospects. 展开更多
关键词 ABSORPTION OXIDATION Multiphase reaction Phosphorus sludge Yellow phosphorus Low temperature
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Classifying moisture sources associated with snowfall in the mountains of Lesotho
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作者 Alexi M.MARINAKI Jennifer M.FITCHETT 《Journal of Mountain Science》 SCIE CSCD 2024年第6期1941-1953,共13页
An average of eight snowfall events occur each year in the eastern Lesotho Highlands.These snowfall events are typically associated with cut-off low(CoLs)systems and mid-latitude cyclones.However,the moisture sources ... An average of eight snowfall events occur each year in the eastern Lesotho Highlands.These snowfall events are typically associated with cut-off low(CoLs)systems and mid-latitude cyclones.However,the moisture sources of the snowfall are unclassified and unclear.The Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)model,an air mass back trajectory model,has been used to evaluate moisture source waters locally in southern Africa and internationally in China and Europe.This study uses HYSPLIT to determine the source moisture of snow in Lesotho.A list of all 82 snowfall events in Lesotho spanning 2017 to 2022 was compiled using the Snow Report SA Instagram page,including the date and location of snowfall.A 72-hour back trajectory for each snowfall event was initiated for both Afriski and the whole of Lesotho.This amounts to models of moisture source trajectories for 28 and 82 snowfall days,respectively.These air mass pathways are classified according to their frequency per snowfall event,per month in the snow season,per year and for the full period.From this,associated moisture source regions and dominant air mass trajectories were identified.This study reports that the air mass trajectories associated with Afriski and Lesotho as a whole are very similar.The most common pathway of air mass trajectories transporting snow-bearing moisture to Lesotho was an inland trajectory from the northern regions of southern Africa.This pathway makes up 16.6%of all trajectories reported and is associated with the Angola Low,the Congo Air Boundary and the St.Helena High Pressure. 展开更多
关键词 Eastern Lesotho Highlands Afriski SNOW Cut-off Lows HYSPLIT Synoptic Climatology
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