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Spontaneous healing of complicated crown-root fractures in children:Two case reports 被引量:1
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作者 Zi-Ling Zhou Lei Gao +5 位作者 Shu-Kai Sun Hong-Shi Li Cai-Di Zhang Wen-Wen Kou Zheng Xu Li-An Wu 《World Journal of Clinical Cases》 SCIE 2022年第18期6298-6306,共9页
BACKGROUND Complicated crown-root fracture is considered a severe dental trauma and is unlikely to heal without treatment.Usually,dentists have to remove the loose coronal fragment of the fractured tooth and treat the... BACKGROUND Complicated crown-root fracture is considered a severe dental trauma and is unlikely to heal without treatment.Usually,dentists have to remove the loose coronal fragment of the fractured tooth and treat the remaining part with multidisciplinary approaches.However,we observed spontaneous healing of fracture in two pediatric cases with a history of complicated crown-root fractures over 4 years ago.CASE SUMMARY In case 1,a 12-year-old boy complained of pain at tooth 11 following an accidental fall 1 d ago.Clinical examination showed a crack line on the crown of tooth 11.Cone beam computed tomography(CBCT)images of tooth 11 showed signs of hard tissue deposition between the fractured fragments.The patient recalled that tooth 11 had struck the floor 1 year ago without seeking any other treatment.In case 2,a 10-year-old girl fell down 1 d ago and wanted to have her teeth examined.Clinical examination showed a fracture line on the crown of tooth 21.CBCT images of tooth 21 also showed signs of hard tissue deposition between the fractured fragments.She also had a history of dental trauma 1 year ago and her tooth 11 received dental treatment by another dentist.According to her periapical radiograph at that time,tooth 21 was fractured 1 year ago and the fracture was overlooked by her dentist.Both of these two cases showed spontaneous healing of complicated crown-root fractures.After over 4 years of follow-up,both fractured teeth showed no signs of abnormality.CONCLUSION These findings may provide new insights and perspectives on the management and treatment of crown-root fractures in children. 展开更多
关键词 Dental trauma Complicated crown-root fracture spontaneous healing CHILDREN Case report
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Correlation between anxiety, depression, and social stress in young patients with thoracolumbar spine fractures
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作者 Bo Wang Da Shi +1 位作者 Yin-Di Sun Bo Dong 《World Journal of Psychiatry》 SCIE 2025年第1期83-92,共10页
BACKGROUND Traumatic injuries,such as falling,car accidents,and crushing mostly cause spinal fractures in young and middle-aged people,and>50%of them are thoracolumbar fractures.This kind of fracture is easily comb... BACKGROUND Traumatic injuries,such as falling,car accidents,and crushing mostly cause spinal fractures in young and middle-aged people,and>50%of them are thoracolumbar fractures.This kind of fracture is easily combined with serious injuries to peripheral nerves and soft tissues,which causes paralysis of the lower limbs if there is no timely rehabilitation treatment.Young patients with thoracolumbar fractures find it difficult to recover after the operation,and they are prone to depression,low self-esteem,and other negative emotions.AIM To investigate the association between anxiety,depression,and social stress in young patients with thoracolumbar spine fractures and the effect on rehabilitation outcomes.METHODS This study retrospectively analyzed 100 patients admitted to the orthopedic department of Honghui Hospital,Xi’an Jiaotong University who underwent thoracolumbar spine fracture surgery from January 2022 to June 2023.The general data of the patients were assessed with the Hamilton anxiety scale(HAMA),Hamilton depression scale(HAMD),life events scale,and social support rating scale(SSRS)to identify the correlation between anxiety,depression scores,and social stress and social support.The Japanese Orthopedic Association(JOA)was utilized to evaluate the rehabilitation outcomes of the patients and to analyze the effects of anxiety and depression scores on rehabilitation.RESULTS According to the scores of HAMD and HAMA in all patients,the prevalence of depression in patients was 39%(39/100),and the prevalence of anxiety was 49%(49/100).Patients were categorized into non-depression(n=61)and depression(n=39),non-anxiety(n=51),and anxiety(n=49)groups.Statistically significant differences in gender,occupation,Pittsburgh Sleep Quality Index(PSQI)score,and monthly family income were observed between the non-depression and depression groups(P<0.05).A significant difference in occupation and PSQI score was found between the non-anxiety and anxiety groups.Both depression(r=0.207,P=0.038)and anxiety scores(r=0.473,P<0.001)were significantly and positively correlated with negative life events.The difference in negative life event scores as well as SSRS total and item scores was statist-ically significant between patients in the non-depression and depression groups(P<0.05).The difference between the non-anxiety and anxiety groups was statistically significant(P<0.05)in the negative life event scores as well as the total SSRS scores.Additionally,JOA scores were significantly lower in both anxious and depressed patients.CONCLUSION Young patients with thoracolumbar fractures are prone to anxiety and depression.Patients’anxiety and depression are closely associated with social pressure,which reduces the life pressure of young patients with thoracolumbar fractures,enhances social support,and improves the psychology of anxiety and depression.,which affects patients’recovery. 展开更多
关键词 Patients with thoracolumbar fractures ANXIETY DEPRESSION Social pressure Social support
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Management of geriatric acetabular fractures:Contemporary treatment strategies
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作者 Theodoros Tosounidis Byron Chalidis 《World Journal of Clinical Cases》 SCIE 2024年第13期2151-2156,共6页
Acetabular fractures in the geriatric population are typically low-energy fractures resulting from a fall from standing height.Compromised bone quality in the elderly,as well as this population’s concomitant medical ... Acetabular fractures in the geriatric population are typically low-energy fractures resulting from a fall from standing height.Compromised bone quality in the elderly,as well as this population’s concomitant medical comorbidities,render the management of such fractures challenging and controversial.Non-operative management remains the mainstay of treatment,although such a choice is associated with numerous and serious complications related to both the hip joint as well as the general condition of the patient.On the other hand,operatively treating acetabular fractures(e.g.,with osteosynthesis or total hip arthroplasty)is gaining popularity.Osteosynthesis can be performed with open reduction and internal fixation or with minimally invasive techniques.Total hip arthroplasty could be performed either in the acute phase combined with osteosynthesis or as a delayed procedure after a period of non-operative management or after failed osteosynthesis of the acetabulum.Regardless of the implemented treatment,orthogeriatric co-management is considered extremely crucial,and it is currently one of the pillars of a successful outcome after an acetabular fracture. 展开更多
关键词 Acetabular fractures Geriatric fractures Fracture fixation Total hip arthroplasty MORTALITY MORBIDITY
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Finite Element Analysis of Coronal Shear Fractures of the Femoral Neck: Displacement of the Femoral Head and Effect of Osteosynthetic Implants
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作者 Yukino Mori Hiroaki Kijima +2 位作者 Mei Terashi Takehiro Iwami Naohisa Miyakoshi 《World Journal of Engineering and Technology》 2024年第3期651-664,共14页
Coronal shear fractures of the femoral neck (CSFF) are the most challenging to treat among proximal femur fractures, directly affecting the life expectancy of patients with osteoporosis. However, an adequate osteosynt... Coronal shear fractures of the femoral neck (CSFF) are the most challenging to treat among proximal femur fractures, directly affecting the life expectancy of patients with osteoporosis. However, an adequate osteosynthesis method has not been elucidated yet. This study investigated the displacement direction of the femoral head fragment and its effect on the bone using finite element method. A finite element model for CSFF was developed from CT image data of a patient with osteoporosis using Mechanical Finder (ver. 11). Subsequently, finite element analyses were performed on six osteosynthesis models under maximum load applied during walking. The compressive stresses, tensile stresses, and compressive strains of each model were examined. The results suggested that the compressive and tensile stress distributions were concentrated on the anterior side of the femoral neck. Compressive strain distribution in the femoral head and neck was concentrated in four areas: at the tip of the blade or lag screw, the anteroinferior side of the blade or lag screw near the fracture site, and the upper right and lower left near the junction of the blade or lag screw and nail. Thus, the distribution of both these stresses revealed that the femoral head fragment was prone to anterior and inferior displacement. Distribution of compressive strains revealed the direction of the stress exerted by the osteosynthetic implant on the bone. The same results were observed in all osteosynthetic implants;thus, the findings could lay the foundation for developing methods for placing osteosynthetic implants less prone to displacement and the osteosynthetic implants themselves. In particular, the study provides insight into the optimal treatment of CSFF. 展开更多
关键词 Finite Element Analysis Proximal Femur fractures Intramedullary Fixation Coronal Shear fractures Femoral Neck
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An analytical model to estimate the time delay to reach spontaneous ignition considering heat loss in oil reservoirs 被引量:1
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作者 James J.Sheng Er-Long Yang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2469-2474,共6页
During air injection into an oil reservoir,an oxidation reaction generates some heat to raise the reservoir temperature.When the reservoir temperature reaches an ignition temperature,spontaneous ignition occurs.There ... During air injection into an oil reservoir,an oxidation reaction generates some heat to raise the reservoir temperature.When the reservoir temperature reaches an ignition temperature,spontaneous ignition occurs.There is a time delay from the injection to ignition.There are mixed results regarding the feasibility of spontaneous ignition in real-field projects and in laboratory experiments.No analytical model is available in the literature to estimate the oxidation time required to reach spontaneous ignition with heat loss.This paper discusses the feasibility of spontaneous ignition from theoretical points and experimental and field project observations.An analytical model considering heat loss is proposed.Analytical models with and without heat loss investigate the factors that affect spontaneous ignition.Based on the discussion and investigations,we find that it is more difficult for spontaneous ignition to occur in laboratory experiments than in oil reservoirs;spontaneous ignition is strongly affected by the initial reservoir temperature,oil activity,and heat loss;spontaneous ignition is only possible when the initial reservoir temperature is high,the oil oxidation rate is high,and the heat loss is low. 展开更多
关键词 spontaneous ignition Time delay Air injection Heat loss Low temperature oxidation COMBUSTION
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Disasters of gas-coal spontaneous combustion in goaf of steeply inclined extra-thick coal seams 被引量:1
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作者 Qiming Zhang Enyuan Wang +2 位作者 Xiaojun Feng Shuxin Liu Dong Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期4141-4153,共13页
In light of the escalating global energy imperatives,mining of challenging-to-access resources,such as steeply inclined extra-thick coal seams(SIEC),has emerged as one of the future trends within the domain of energy ... In light of the escalating global energy imperatives,mining of challenging-to-access resources,such as steeply inclined extra-thick coal seams(SIEC),has emerged as one of the future trends within the domain of energy advancement.However,there is a risk of gas and coal spontaneous combustion coupling disasters(GCC)within the goaf of SIEC due to the complex goaf structure engendered by the unique mining methodologies of SIEC.To ensure that SIEC is mined safely and efficiently,this study conducts research on the GCC within the goaf of SIEC using field observation,theoretical analysis,and numerical modeling.The results demonstrate that the dip angle,the structural dimensions in terms of width-to-length ratio,and compressive strength of the overlying rock are the key factors contributing to the goaf instability of SIEC.The gangue was asymmetrically filled,primarily accumulating within the central and lower portions of the goaf,and the filling height increased proportionally with the advancing caving height,the expansion coefficient,and the thickness of the surrounding rock formation.The GCC occurs in the goaf of SIEC,with an air-return side range of 41 m and an air-intake side range of 14 m,at the intersection area of the“<”-shaped oxygen concentration distribution(coal spontaneous combustion)and the“>”-shaped gas concentration distribution(gas explosion).The optimal nitrogen flow rate is 1000 m3/h with an injection port situated 25 m away from the working face for the highest nitrogen diffusion efficacy and lowest risk of gas explosion,coal spontaneous combustion,and GCC.It has significant engineering applications for ensuring the safe mining of SIEC threatened by the GCC. 展开更多
关键词 Steeply inclined extra-thick coal seams Gas explosion Coal spontaneous combustion Coupling disaster Numerical simulation
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Intravascular photoacoustic and optical coherence tomography imaging dual-mode system for detecting spontaneous coronary artery dissection: A feasibility study 被引量:1
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作者 Yongwei Wang Yuyang Wan Zhongjiang Chen 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第1期77-86,共10页
In this work,we present an intravascular dual-mode endoscopic system capable of both intravascular photoacoustic imaging(IVPAI)and intravascular optical coherence tomography(IVOCT)for recognizing spontaneous coronary ... In this work,we present an intravascular dual-mode endoscopic system capable of both intravascular photoacoustic imaging(IVPAI)and intravascular optical coherence tomography(IVOCT)for recognizing spontaneous coronary artery dissection(SCAD)phantoms.IVPAI provides high-resolution and high-penetration images of intramural hematoma(IMH)at different depths,so it is especially useful for imaging deep blood clots associated with imaging phantoms.IVOCT can readily visualize the double-lumen morphology of blood vessel walls to identify intimal tears.We also demonstrate the capability of this dual-mode endoscopic system using mimicking phantoms and biological samples of blood clots in ex vivo porcine arteries.The results of the experiments indicate that the combined IVPAI and IVOCT technique has the potential to provide a more accurate SCAD assessment method for clinical applications. 展开更多
关键词 spontaneous coronary artery dissection(SCAD) intravascular optical coherence tomography(IVOCT) intravascular photoacoustic imaging(IVPAI)
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The effects of various factors on spontaneous imbibition in tight oil reservoirs
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作者 Cheng Liu Tian-Ru Wang +3 位作者 Qing You Yue-Chun Du Guang Zhao Cai-Li Dai 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期315-326,共12页
Slickwater fracturing fluids have gained widespread application in the development of tight oil reservoirs. After the fracturing process, the active components present in slickwater can directly induce spontaneous imb... Slickwater fracturing fluids have gained widespread application in the development of tight oil reservoirs. After the fracturing process, the active components present in slickwater can directly induce spontaneous imbibition within the reservoir. Several variables influence the eventual recovery rate within this procedure, including slickwater composition, formation temperature, degree of reservoir fracture development, and the reservoir characteristics. Nonetheless, the underlying mechanisms governing these influences remain relatively understudied. In this investigation, using the Chang-7 block of the Changqing Oilfield as the study site, we employ EM-30 slickwater fracturing fluid to explore the effects of the drag-reducing agent concentration, imbibition temperature, core permeability, and core fracture development on spontaneous imbibition. An elevated drag-reducing agent concentration is observed to diminish the degree of medium and small pore utilization. Furthermore, higher temperatures and an augmented permeability enhance the fluid flow properties, thereby contributing to an increased utilization rate across all pore sizes. Reduced fracture development results in a lower fluid utilization across diverse pore types. This study deepens our understanding of the pivotal factors affecting spontaneous imbibition in tight reservoirs following fracturing. The findings act as theoretical, technical, and scientific foundations for optimizing fracturing strategies in tight oil reservoir transformations. 展开更多
关键词 Tight oil reservoir spontaneous imbibition Nuclear magnetic resonance Slickwater fracturing fluid Fluid utilization degree
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Hydroxychloroquine: A Safe, Effective and Inexpensive Maintenance Therapy for Chronic Spontaneous Urticaria
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作者 Kamel El-Reshaid Shaima Al-Bader Abdulla Al-Refaee 《International Journal of Clinical Medicine》 CAS 2024年第6期225-232,共8页
Background: Chronic spontaneous urticaria (CSU) is an autoimmune skin disorder that lasts for >6 weeks and may last for years. It is a disabling skin disease that impairs quality of life. Set-up treatment with anti... Background: Chronic spontaneous urticaria (CSU) is an autoimmune skin disorder that lasts for >6 weeks and may last for years. It is a disabling skin disease that impairs quality of life. Set-up treatment with antihistamines, immunosuppressives, immune modulators and lately Omalizumab are expensive or have significant side effects. In this retrospective study, we describe our experience with the use of hydroxychloroquine (HCQ) as a maintenance therapy for those with severe forms of CSU after Corticosteroids (C) induction phase. Patients and Methods: 16 adult patients (aged 44 ± 7) with severe CSU for 5 ± 1 months, were included in the study. Eight patients had attacks of angioneurotic oedema. Their previous treatments were antihistaminic and short-courses of C. Results: After 2 weeks of remission with C and HCQ 200 mg twice daily, the dose of C was tapered down and discontinued by the end of the first month. The seven days Urticaria Activity Score decreased from 30 ± 3 to 6 ± 1 by the first month and remained low at 3 ± 1 by the end of 2 years of follow-up. Moreover, IgE levels and CRP had similar trends. Remission persisted after 37 ± 9 months of follow-up. Conclusion: HCQ is a safe, efficacious and inexpensive drug for the treatment of CSU. 展开更多
关键词 Autoimmune Disease Chronic spontaneous Urticaria CORTICOSTEROIDS HYDROXYCHLOROQUINE OMALIZUMAB
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Risk Factors Recurrence of Spontaneous Ascitic Fluid Infection (Slai) in Cirrhotic Patients
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作者 Diallo Mamadou Sarifou Ottou Onana Christian Lionel +3 位作者 Soro Dramane Youssouf Oumarou Yaogo Abdoulatif Lohoues-Kouacou Marie Jeanne 《Open Journal of Gastroenterology》 CAS 2024年第8期249-260,共12页
Introduction: After an episode of spontaneous infection of ascitic fluid (ISLA). The recurrence of ISLA at one year is greater than 70%. We studied the risk factors associated with the occurrence of recurrence. Patien... Introduction: After an episode of spontaneous infection of ascitic fluid (ISLA). The recurrence of ISLA at one year is greater than 70%. We studied the risk factors associated with the occurrence of recurrence. Patients and methods: this was a retrospective, descriptive and analytical study of patient files, hospitalized in the department for 12 months, the choice of the sample was of convenience. Results: We have 1347 patient files collected including 389 cases of cirrhosis. We had 37 files of cirrhotic patients with ISLA including 28 cures without recurrence of ISLA, 08 files of patients with recurrence of ISLA and 03 excluded, i.e. a hospital prevalence of recurrence of 0.6% and a prevalence in cirrhotic patients of 23.5%. The most common antecedents were: hospital contact recent (35.3%), the concept of iterative ascites punctures (32.3%), the presence of HCC (29.4%), hepatic encephalopathy (20.6%) and digestive hemorrhage (14.7%). In univariate analysis, recent digestive bleeding was associated with an increased risk of recurrence (OR 7.2, 95% CI 0.96 - 67.1). HBV (62.5%) is the main etiology of cirrhosis. The PNN rate at 250 - 499 mm3 (62.5%), the protein level 3 (75%). Patients on secondary prophylaxis with NORFLOXACIN were 25%. Recurrence of ISLA was treated with CEFTRIAXONE 2 g/24 hours. Conclusion: Recurrence of ISLA is serious, the predictive factors for recurrence are, hospital contact recent, the concept of iterative ascites punctures, the presence of HCC, the presence of hepatic encephalopathy and digestive bleeding. 展开更多
关键词 Antibiotic CIRRHOSIS Risk factors spontaneous Ascitic Fluid Infection RECURRENCE
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Stress tensor determination by modified hydraulic tests on pre-existing fractures:Method and stress constraints
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作者 Guiyun Gao Chenghu Wang Ke Gao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1637-1648,共12页
The hydraulic testing of pre-existing fractures(HTPF)is one of the most promising in situ stress measurement methods,particularly for three-dimensional stress tensor determination.However,the stress tensor determinati... The hydraulic testing of pre-existing fractures(HTPF)is one of the most promising in situ stress measurement methods,particularly for three-dimensional stress tensor determination.However,the stress tensor determination based on the HTPF method requires at least six tests or a minimum of 14-15 tests(under different conditions)for reliable results.In this study,we modified the HTPF method by considering the shear stress on each pre-existing fracture,which increased the number of equations for the stress tensor determination and decreased the number of tests required.Different shear stresses were attributed to different fractures by random sampling;therefore,the stress tensors were obtained by searching for the optimal solution using the least squares criterion based on the Monte Carlo method.Thereafter,we constrained the stress tensor based on the tensile strength criterion,compressive strength criterion,and vertical stress constraints.The inverted stress tensors were presented and analyzed based on the tensorial nature of the stress using the Euclidean mean stress tensor.Two stress-measurement campaigns in Weifang(Shandong Province,China)and Mercantour road tunnel(France)were implemented to highlight the validity and efficiency of the modified HTPF(M-HTPF)method.The results showed that the M-HTPF method can be applied for stress tensor inversion using only three to four tests on pre-existing fractures,neglecting the stress gradient.The inversion results were confined to relatively small distribution dispersions and were significantly reliable and stable due to the shear stresses on the fractures and the stress constraints employed.The M-HTPF method is highly feasible and efficient for complete stress tensor determination in a single borehole. 展开更多
关键词 Stress tensor Hydraulic tests on pre-existing fractures Mean stress Stress constraint Hydraulic fracturing
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Effect and Mechanism of Rare Earth Hydrotalcite Inhibiting Coal Spontaneous Combustion
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作者 张小娟 LIU Bo +1 位作者 罗振敏 SUN Lu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期50-59,共10页
A hydrotalcite(layered double hydroxide, LDH) inhibitor which is suitable for the whole process of coal spontaneous combustion and a LDH inhibitor containing rare earth lanthanum elements were prepared. The inhibition... A hydrotalcite(layered double hydroxide, LDH) inhibitor which is suitable for the whole process of coal spontaneous combustion and a LDH inhibitor containing rare earth lanthanum elements were prepared. The inhibition effect and mechanism were analyzed by scanning electron microscopy(SEM),X-ray diffraction(XRD), thermal performance analysis, in-situ diffuse reflectance infrared spectroscopy and temperature-programmed experiment. The results have shown that the inhibitor containing lanthanum can play a good inhibitory role in every stage of coal oxidation. During the slow oxidation of coal samples, the inhibitor containing lanthanum ions can slow down the oxidation process of coal and increase the initial temperature of coal spontaneous combustion. At the same time, because the hydroxyl groups in LDHs are connected with-COO-groups on the coal surface through hydrogen bonds, the stability of coal is improved. With the increase of temperature, LDHs can remove interlayer water molecules and reduce the surface temperature of coal. CO release rate of coal samples decreases significantly after adding inhibitor containing lanthanum element, and the maximum inhibition rate of the inhibitor is 58.1%. 展开更多
关键词 rare earth HYDROTALCITE coal spontaneous combustion MECHANISM
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Prophylactic Pattern Scanning Laser Retinal Photocoagulation for Diabetic Retinopathy in Spontaneously Diabetic Torii Fatty Rats: Preliminary Experimental Results
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作者 Rina Takagi Yoshiaki Tanaka +6 位作者 Tetsuya Hasegawa Masami Shinohara Yasushi Kageyama Tomohiko Sasase Machiko Shimmura-Tomita Akihiro Kakehashi Toshikatsu Kaburaki 《Journal of Diabetes Mellitus》 CAS 2024年第3期153-165,共13页
Research Background and Purpose: The number of diabetic patients is rapidly increasing, making it crucial to find methods to prevent diabetic retinopathy (DR), a leading cause of blindness. We investigated the effects... Research Background and Purpose: The number of diabetic patients is rapidly increasing, making it crucial to find methods to prevent diabetic retinopathy (DR), a leading cause of blindness. We investigated the effects of prophylactic pattern scanning laser retinal photocoagulation on DR development in Spontaneously Diabetic Torii (SDT) fatty rats as a new prevention approach. Methods: Photocoagulation was applied to the right eyes of 8-week-old Spontaneously Diabetic Torii (SDT) fatty rats, with the left eyes serving as untreated controls. Electroretinography at 9 and 39 weeks of age and pathological examinations, including immunohistochemistry for vascular endothelial growth factor and glial fibrillary acidic protein at 24 and 40 weeks of age, were performed on both eyes. Results: There were no significant differences in amplitude and prolongation of the OP waves between the right and left eyes in SDT fatty rats at 39 weeks of age. Similarly, no significant differences in pathology and immunohistochemistry were observed between the right and left eyes in SDT fatty rats at 24 and 40 weeks of age. Conclusion: Prophylactic pattern scanning retinal laser photocoagulation did not affect the development of diabetic retinopathy in SDT fatty rats. 展开更多
关键词 Diabetes Pattern Scanning Laser Diabetic Retinopathy spontaneously Diabetic Torii Fatty Rats ELECTRORETINOGRAPHY
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Fractal model of spontaneous imbibition in low-permeability reservoirs coupled with heterogeneity of pore seepage channels and threshold pressure
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作者 Ming-Sheng Zuo Hao Chen +3 位作者 Xi-Liang Liu Hai-Peng Liu Yi Wu Xin-Yu Qi 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1002-1017,共16页
Spontaneous imbibition(SI)is an important mechanism for enhancing oil recovery in low-permeability reservoirs.Due to the strong heterogeneity,and the non-Darcy flow,the construction of SI model for lowpermeability res... Spontaneous imbibition(SI)is an important mechanism for enhancing oil recovery in low-permeability reservoirs.Due to the strong heterogeneity,and the non-Darcy flow,the construction of SI model for lowpermeability reservoirs is extremely challenging.Commonly,traditional SI models based on single or averaged capillary tortuosity ignore the influence of heterogeneity of pore seepage channels and the threshold pressure(TP)on imbibition.Therefore,in this work,based on capillary model and fractal theory,a mathematical model of characterizing SI considering heterogeneity of pore seepage channels is established.On this basis,the threshold pressure was introduced to determine the pore radius at which the wetted phase can displace oil.The proposed new SI model was verified by imbibition experimental data.The study shows that for weakly heterogeneous cores with permeability of 0-1 m D,the traditional SI model can characterize the imbibition process relatively accurately,and the new imbibition model can increase the coefficient of determination by 1.05 times.However,traditional model has serious deviations in predicting the imbibition recovery for cores with permeability of 10-50 m D.The new SI model coupling with heterogeneity of pore seepage channels and threshold pressure effectively solves this problem,and the determination coefficient is increased from 0.344 to 0.922,which is increased by2.68 times.For low-permeability reservoirs,the production of the oil in transitional pores(0.01-0.1μm)and mesopores(0.1-1μm)significantly affects the imbibition recovery,as the research shows that when the heterogeneity of pore seepage channels is ignored,the oil recovery in transitional pores and mesopores decreases by 7.54%and 4.26%,respectively.Sensitivity analysis shows that increasing interfacial tension,decreasing contact angle,oil-water viscosity ratio and threshold pressure will increase imbibition recovery.In addition,there are critical values for the influence of these factors on the imbibition recovery,which provides theoretical support for surfactant optimization. 展开更多
关键词 spontaneous imbibition Low-permeability reservoir Fractal model Threshold pressure Capillary tube
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Spontaneous Recovery in Directed Dynamical Networks
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作者 Xueming Liu Xian Yan H.Eugene Stanley 《Engineering》 SCIE EI CAS CSCD 2024年第6期208-214,共7页
Complex networked systems,which range from biological systems in the natural world to infrastructure systems in the human-made world,can exhibit spontaneous recovery after a failure;for example,a brain may spontaneous... Complex networked systems,which range from biological systems in the natural world to infrastructure systems in the human-made world,can exhibit spontaneous recovery after a failure;for example,a brain may spontaneously return to normal after a seizure,and traffic flow can become smooth again after a jam.Previous studies on the spontaneous recovery of dynamical networks have been limited to undirected networks.However,most real-world networks are directed.To fill this gap,we build a model in which nodes may alternately fail and recover,and we develop a theoretical tool to analyze the recovery properties of directed dynamical networks.We find that the tool can accurately predict the final fraction of active nodes,and the prediction accuracy decreases as the fraction of bidirectional links in the network increases,which emphasizes the importance of directionality in network dynamics.Due to different initial states,directed dynamical networks may show alternative stable states under the same control parameter,exhibiting hysteresis behavior.In addition,for networks with finite sizes,the fraction of active nodes may jump back and forth between high and low states,mimicking repetitive failure-recovery processes.These findings could help clarify the system recovery mechanism and enable better design of networked systems with high resilience. 展开更多
关键词 Network resilience Directed dynamical networks spontaneous recovery
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Underlying anti-hypertensive mechanism of the Mizuhopecten yessoensis derived peptide NCW in spontaneously hypertensive rats via widely targeted kidney metabolomics
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作者 Wenjun Xue Wenzhu Zhao +1 位作者 Sijia Wu Zhipeng Yu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期472-481,共10页
The angiotensin-converting enzyme(ACE)inhibitory peptide NCW derived from Mizuhopecten yessoensis has been demonstrated to have significant in vivo anti-hypertensive effects,however,its anti-hypertensive mechanism is ... The angiotensin-converting enzyme(ACE)inhibitory peptide NCW derived from Mizuhopecten yessoensis has been demonstrated to have significant in vivo anti-hypertensive effects,however,its anti-hypertensive mechanism is still not fully clarified.This study established a UPLC-Q-TRAP-MS/MS-based widely targeted kidney metabolomics approach to explore the changes of kidney metabolic profiles and to clarify the antihypertensive mechanism of peptide NCW in spontaneously hypertensive rats(SHRs).Multivariate statistical analysis indicated that the kidney metabolic profiles were clearly separated between the SHR-NCW and SHRUntreated groups.A total of 85 metabolites were differentially regulated,and 16 metabolites were identified as potential kidney biomarkers,e.g.,3-hydroxybutyrate,malonic acid,deoxycytidine,and L-aspartic acid.The peptide NCW might regulate kidney metabolic disorder of SHRs to alleviate hypertension by suppressing inflammation and improving nitric oxide production under the regulation of linoleic acid metabolism,folate related pathways,synthesis and degradation of ketone bodies,pyrimidine metabolism,β-alanine metabolism,and retinal metabolism. 展开更多
关键词 ACE inhibitory peptide KIDNEY MECHANISM Metabolomics spontaneously hypertensive rats
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Spontaneous Abortions in the Second Trimester of Pregnancy: Research and Analysis of Factors Associated at Laquintinie Hospital in Douala
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作者 Henri Essome Moustapha Bilkissou +13 位作者 Merlin Boten Bounyom Sandrine Ngoumi Ingrid Doriane Ofakem Ilick Astrid Ndolo Kondo Fulbert Mangala Nkwele Michel Roger Ekono Alphonse Ngalame Nyong Robert Tchounzou Junie Ngaha Yaneu Marga Vanina Ngono Akam Gervais Mounchikpou Ngouhouo Grâce Tocki Toutou Théophile Nana Njamen Pascal Foumane 《Open Journal of Obstetrics and Gynecology》 2024年第8期1130-1143,共14页
Introduction: Spontaneous abortion of the second trimester is an interruption of pregnancy with complete expulsion or not of the product of conception between 15 and 28 weeks of pregnancy without any maneuvers. The ob... Introduction: Spontaneous abortion of the second trimester is an interruption of pregnancy with complete expulsion or not of the product of conception between 15 and 28 weeks of pregnancy without any maneuvers. The objective of our study was to determine the factors associated with second trimester spontaneous abortions at Laquintinie Hospital in Douala. Methodology for this purpose: We conducted a case-control study from January to May 2019 on pregnant women who may or may not have had spontaneous second trimester abortions. Results: In total we recorded 1609 pregnancies and recruited 184 patients, including 46 cases and 138 controls;which gave a frequency of spontaneous abortion in the second trimester of pregnancy of 2.85%. A correlative analysis showed that spontaneous abortions in the second trimester were associated with housewife status (OR = 2.89;CI = 1.21 - 6.79;p = 0.010), gestation > 5 (OR = 4.09;CI = 1.02 - 17.66;p = 0.040), multiparity (OR = 3.81;CI = 1.59 - 9.16;p = 0.002), history of endouterine maneuvers (OR = 5.64;CI = 2.43 - 13 .03;p = 0.000), malaria in pregnancy (OR = 3.99;CI = 1.1 - 14.76;p = 0.030), incompleteness on the second trimester ultrasound (OR = 2.37;CI = 1.18 - 4.70;p = 0.010), jolts when traveling (OR = 46.04;CI = 17.29 - 123.66;p = 0.000), long car journeys (OR = 7.05;CI = 1.99 - 27.77;p = 0.000). After logistic regression eliminating the confounding factors, only the following were associated with abortions: Multiparity (OR = 13.90;CI = 2.96 - 65.18;p = 0.000), endo uterine maneuvers (OR = 3.69;CI = 1. 01 - 13.44;p = 0.047), jolts when traveling (OR = 72.63;CI = 19.47 - 270.96;p = 0.000), long car journeys (OR = 15.41;CI = 2.7 - 85, 95;p = 0.000). Conclusion: Our study reveals that a set of factors contribute to the occurrence of spontaneous abortions in the second trimester of pregnancy in our context. 展开更多
关键词 spontaneous Abortion Second Trimester Associated Factors Laquintinie
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Management of Spontaneous Intracerebral Haemorrhage (sICH) at the University Hospital of Brazzaville (CONGO)
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作者 Ekouele Mbaki Hugues Brieux Ngoma Niangui Léocia Exaucée +5 位作者 Diatewa Josué Euberma Boukaka Kala Rel Gerald Ngackosso Olivier Brice Mpandzou Ghislain Armel Boukassa Léon Ossou-Nguiet Paul Macaire 《Neuroscience & Medicine》 2024年第1期23-38,共16页
Spontaneous intracerebral haemorrhage (sICH) is characterised by bleeding within the brain parenchyma, without any accompanying vascular malformation, parenchymal abnormality or coagulation disorder. The study aimed t... Spontaneous intracerebral haemorrhage (sICH) is characterised by bleeding within the brain parenchyma, without any accompanying vascular malformation, parenchymal abnormality or coagulation disorder. The study aimed to depict the management of sICH at the University Hospital of Brazzaville (UHB). It was an observational, descriptive, and cross-sectional analysis. Data collection was conducted retrospectively, covering the period from January 1, 2020 to August 31, 2022, spanning two years and eight months. The study examined socio-demographic, diagnostic, therapeutic, and evolutionary variables. We included 274 cases. We observed 160 men (58.4%) and 114 women (41.6%), resulting in a sex ratio of 1.4. The mean age was 55.3 ± 11.4 years, with ages ranging from 31 to 93 years. The detection of sICH was typically a result of experiencing motor deficits (59.5%) or disorders of consciousness (37.2%). The weightiness of one half of the body was the most common reason for seeking medical advice. Hematoma was capsulo-lenticular in 159 cases (58%) and capsulo-thalamic in 63 cases (23%). Hematomas were <30 ml in 162 cases (59.1%) and >30 ml in 112 cases (40.9%), and associated with hydrocephalus in 11.7% of cases. Conservative medical treatment was administered in 257 cases (94.2%) while surgical treatment was performed in 16 cases (5.8%). The surgical techniques used were external ventricular drainage (EVD) in 2 cases, ventriculo-peritoneal shunt in 5 cases, and hematoma evacuation in 10 cases. Death occurred before the 7th day of hospitalisation in 73 cases (57.8%) and after in 46 cases (42.2%). The median time to death was four days (Q1 = 2 days;Q3 = 7 days), with extremes of 0 and 216 days. . 展开更多
关键词 spontaneous Intracerebral haemorrhage MANAGEMENT BRAZZAVILLE
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Management of Mandibular Fractures in Children in Ivory Coast: Experience of the Stomatology and Maxillofacial Surgery Department at the University Hospital of Cocody from 2000 to 2019
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作者 Bakary Ouattara Camille Assouan +8 位作者 Laurent Boka Koffi Konan René Kouakou Ake Lucien Jonathan Yapo Annick Zoglo-Bro Ahi Morel Mounin Chapo Affoué Linda Marie Pierre Koffi Kahder Morel Diarra Atse Kobo N’Guessan Konan Marc Koffi 《Open Journal of Stomatology》 2024年第7期341-349,共9页
Introduction: Mandibular fractures in children are becoming increasingly common. Treatment of these fractures is difficult due to their anatomical and physiological complexity. Therefore, there is a need for well-codi... Introduction: Mandibular fractures in children are becoming increasingly common. Treatment of these fractures is difficult due to their anatomical and physiological complexity. Therefore, there is a need for well-codified management. Our main aim was to develop a decision algorithm for the management of mandibular fractures in children based on our experience. Materials and Methods: This was a retrospective descriptive study carried out in the Department of Stomatology and Maxillofacial Surgery at the University Hospital of Cocody over a period of 20 years (2000-2019). Results: We enrolled 58 patients. The mean age of the patients was 9.35 ± 2.3 years with a sex ratio of 2.22. Traffic accidents were the main cause of mandibular fractures (60.35%). Condylar fractures were the most common (46.87%). Treatment was orthopedic in 45.76% of cases, mixed (orthopedic and surgical) in 24.14% and surgical in 5.17%. Patients were followed up weekly for 1 month, then monthly for 6 months and annually for 3 years, with panoramic radiographs of the maxilla starting at 21 days. We observed 2 cases of complications: temporomandibular ankylosis and gingival stomatitis. Conclusion: Mandibular fractures are common in children. Management is difficult due to anatomical and physiological peculiarities. The choice of treatment depends on several criteria. 展开更多
关键词 fractures MANDIBLE CHILDREN Treatment Ivory Coast
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Development characteristics and controlling factors of fractures in lacustrine shale and their geological significance for evaluating shale oil sweet spots in the third member of the Shahejie Formation in the Qikou Sag, Bohai Bay Basin
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作者 Xu Zeng Tao Yang +5 位作者 Jian-Wei Feng Cong-Sheng Bian Ming Guan Wei Liu Bing-Cheng Guo Jin Dong 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期791-805,共15页
Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fra... Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fractures, remain controversial. In this study, we integrate thin section analysis and microcomputed tomography(CT) data from several lacustrine shale samples from the third member(Es3) of the Shahejie Formation, Qikou Sag, Bohai Bay Basin, to assess the fractures in detail. The goal is to reveal the development characteristics, controlling factors, and geological significance for evaluating sweet spots in a shale oil play. The fractures in the Es3contain high-angle structural and horizontal bed-parallel fractures that are mostly shear and extensional. Various factors influence fracture development,including lithofacies, mineral composition, organic matter content, and the number of laminae. Structural fractures occur predominantly in siltstone, whereas bed-parallel fractures are abundant in laminated shale and layered mudstone. A higher quartz content results in higher shale brittleness, causing fractures, whereas the transformation between clay minerals contributes to the development of bedparallel fractures. Excess pore pressure due to hydrocarbon generation and expulsion during thermal advance can cause the formation of bed-parallel fractures. The density of the bed-parallel and structural fractures increases with the lamina density, and the bed-parallel fractures are more sensitive to the number of laminae. The fractures are critical storage spaces and flow conduits and are indicative of sweet spots. The laminated shale in the Es3with a high organic matter content contains natural fractures and is an organic-rich, liquid-rich, self-sourced shale play. Conversely, the siltstone, massive mudstone, and argillaceous carbonate lithofacies contain lower amounts of organic matter and do not have bed-parallel fractures. However, good reservoirs can form in these areas when structural fractures are present and the source, and storage spaces are separated. 展开更多
关键词 fractures Development characteristics Controlling factors Shale oil Sweet spot
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