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Lipomatous ependymoma with ZFTA:RELA fusion-positive:A case report
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作者 Xiao-Yu Zhao Juan-Han Yu +4 位作者 Yi-Hua Wang Yi-Xin Liu Lu Xu Lin Fu Ning Yi 《World Journal of Clinical Cases》 SCIE 2025年第1期48-55,共8页
BACKGROUND Ependymoma with lipomatous differentiation is a rare type of ependymoma.The ZFTA fusion-positive supratentorial ependymoma is a novel tumor type in the 2021 World Health Organization classification of centr... BACKGROUND Ependymoma with lipomatous differentiation is a rare type of ependymoma.The ZFTA fusion-positive supratentorial ependymoma is a novel tumor type in the 2021 World Health Organization classification of central nervous system tumors.ZFTA fusion-positive lipomatous ependymoma has not been reported to date.CASE SUMMARY We reported a case of a 15-year-old Chinese male who had a sudden convulsion lasting approximately six minutes.Magnetic resonance imaging showed a round cystic shadow of approximately 1.9 cm×1.5 cm×1.9 cm under the right parieto-occipital cortex.Microscopic examination showed characteristic perivascular pseudorosettes and adipose differentiation in the cytoplasm.Immunohisto-chemical staining showed that the tumor cells were negative for cytokeratin,NeuN,Syn and p53,but positive for GFAP,vimentin and S-100 protein.Signi-ficant punctate intracytoplasmic EMA immunoreactivity was observed.The level of Ki-67 was about 5%.Genetic analysis revealed ZFTA:RELA fusion.A cranio-tomy with total excision of the tumor was performed.The follow-up time was 36 months,no evidence of disease recurrence was found in magnetic resonance imaging.CONCLUSION Based on these findings,the patient was diagnosed as a ependymoma with ZFTA fusion and lipomatous differentiation.This case report provides information on the microscopic morphological features of ependymoma with ZFTA fusion and lipomatous differentiation,which can help pathologists to make a definitive diagnosis of this tumor. 展开更多
关键词 EPENDYMOMA Lipomatous Molecular classification SUPRATENTORIAL ZFTA:RELA fusion Case report
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Wilson's disease in two siblings from Ecuador:Two case reports
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作者 Enrique Carrera Jonathan Alvarado +1 位作者 Martina Astudillo Galo Pillajo 《World Journal of Clinical Cases》 SCIE 2025年第3期50-60,共11页
BACKGROUND Wilson's disease(WD)is a rare metabolic disorder of copper accumulation in organs such as liver,brain,and cornea.Diagnoses and treatments are challenging in settings,where advanced diagnostic tests are ... BACKGROUND Wilson's disease(WD)is a rare metabolic disorder of copper accumulation in organs such as liver,brain,and cornea.Diagnoses and treatments are challenging in settings,where advanced diagnostic tests are unavailable,copper chelating agents are frequently scarce,healthcare professionals lack disease awareness,and medical follow-ups are limited.Prompt diagnoses and treatments help prevent complications,improve patients’quality of life,and ensure a normal life expectancy.The clinical presentations and outcomes of WD can vary within a single family.CASE SUMMARY We present the cases of two siblings(19 and 27 years)from a consanguineous family in rural Ecuador,diagnosed as having WD during a family screening.The male patient,diagnosed at age 19 after his brother’s death from acute liver failure,presented with compensated cirrhosis,neurological symptoms,and bilateral Kayser-Fleischer rings.He developed progressive neurological deterioration during an irregular treatment with D-penicillamine due to medication shortages.His condition improved upon switching to trientine tetrahydrochloride,and his neurological symptoms improved over an 8-year period of follow-ups.The female patient,diagnosed at age 10,exhibited only biochemical alterations.Her treatment history was similar;however,she remained asymptomatic without disease progression over the same follow-up period.We discuss the potential influence of epigenetic mechanisms and modifier genes on the various phenotypes,emphasizing the need for research in these areas to optimize therapeutic strategies.CONCLUSION Our patients’medical histories show how early diagnosis and treatment can prevent disease progression;and,how suboptimal treatments impact disease outcomes. 展开更多
关键词 Wilson disease Kayser-Fleischer rings Copper chelator D-PENICILLAMINE Trientine tetrahydrochloride Case report
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Bullous pemphigoid associated with acquired hemophilia A: A case report
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作者 Su-Ye Hu Meng-Can Li +7 位作者 Zi-Jia Hao Xu-Ya Chai Pei-Sai Li Yang Liu Li-Xia Liu Ying Xu Pan-Pan Yang Ling-E Li 《World Journal of Clinical Cases》 SCIE 2025年第4期28-33,共6页
BACKGROUND Acquired hemophilia A (AHA) is a rare and potentially severe bleeding disordercaused by circulating autoantibodies against factor Ⅷ (FⅧ). In approximately50% of the patients, the condition is associated w... BACKGROUND Acquired hemophilia A (AHA) is a rare and potentially severe bleeding disordercaused by circulating autoantibodies against factor Ⅷ (FⅧ). In approximately50% of the patients, the condition is associated with autoimmune diseases,cancers, medication use, pregnancy, and the post-partum period. Bullous pemphigoid(BP) is a chronic autoimmune subepidermal blistering disease associatedwith tissue-bound and circulating autoantibodies against BP antigens 180 (BP180)and 230 (BP230). AHA-associated BP has a high mortality rate;hence, the understandingof this disease must improve.CASE SUMMARY A 69-year-old man presented with erythema, blisters, blood blisters, and crustsaccompanied by severe pruritus for more than 20 days, and ecchymosis andswelling on his left upper arm for 3 days. Pathological examination revealed asubepidermal blister that contained eosinophils. Laboratory tests showed that theBP180 autoantibody levels had increased, isolated activated partial thromboplastintime was notably prolonged (115.6 s), and coagulation FⅧ activity wasextremely low (< 1.0%). Furthermore, the FⅧ inhibitor titer had greatlyincreased (59.2 Bethesda units). Therefore, the patient was diagnosed as having BP associated with AHA, prescribed 0.05% topical halometasone cream, and transferred to a higher-level hospitalfor effective treatment;however, he died after 2 days.CONCLUSION AHA associated BP is rare, dangerous, and has a high mortality rate. Therefore, its timely diagnosis and effectivetreatment are necessary. 展开更多
关键词 Bullous pemphigoid Acquired hemophilia A Acquired hemophilia A FactorⅧ Case report
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Extramedullary plasmacytoma with the uvula as first affected site:A case report
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作者 Jing Yang Hui Peng +2 位作者 Sheng-Ke Tu Min Li Kui Song 《World Journal of Clinical Oncology》 2025年第1期53-58,共6页
BACKGROUND Extramedullary plasmacytoma(EMP)represents one of the rarer forms of plasma cell malignancies,capable of impacting a variety of tissues and organs throughout the body.The majority of EMP cases are predomina... BACKGROUND Extramedullary plasmacytoma(EMP)represents one of the rarer forms of plasma cell malignancies,capable of impacting a variety of tissues and organs throughout the body.The majority of EMP cases are predominantly found in the head and neck region,especially within the laryngopharynx,as well as in the gastrointestinal tract.While there have been documented instances of oropharyngeal involvement in EMP cases in the academic literature,it is important to note that EMP specifically affecting the uvula is exceedingly uncommon.Furthermore,it is noteworthy that over 60% of epithelial carcinomas in the upper respiratory tract and oropharynx tend to metastasize to the cervical lymph nodes,indicating a propensity for regional spread in these types of cancers.In this context,we present a rare case of extramedullary plasmacytoma where the uvula served as the initially affected site.This case emphasizes the need for heightened awareness among clinicians regarding such unusual comorbidities,as early recognition and diagnosis can significantly influence patient management and treatment outcomes.In addition,a review of the relevant literature is included to further educate and inform healthcare professionals about this rare presentation,ultimately aiming to enhance clinical understanding and improve patient care in similar situations.CASE SUMMARY A 51-year-old man was admitted to our hospital because of a slowly enlarging neck mass.A physical examination revealed a palpable left lymph node,and magnetic resonance imaging(MRI)of the oropharynx and the neck showed a soft tissue mass in the oropharynx and enlargement of multiple lymph nodes in the neck.The soft tissue mass was diagnosed as plasmacytoma by immunohistochemical analysis.Monoclonal immunoglobulins and bone marrow biopsy showed normal results.Therefore,we diagnosed that as EMP of the uvula.After four cycles of adjuvant chemotherapy dominated by bortezomib,MRI reexamination showed a significant reduction of the mass in the oropharynx and the cervical lymph nodes.Afterwards,the λ light chain returned to normal levels.There was no evidence of evolution to multiple myeloma.CONCLUSION We have reported a rare case of extramedullary plasmacytoma with the uvula as the first affected site and the relevant literature is reviewed to improve clinicians'awareness of such rare comorbidities. 展开更多
关键词 Extramedullary plasmacytoma PLASMACYTOMA UVULA Multiple myeloma Case report
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Cerebral fat embolism following autologous fat injection in facial reconstruction:A case report
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作者 Xiu-Ying Chen Fa Shen +4 位作者 Chang Cheng Yu-Han Wang Wen-Chao Cheng De-Zhi Yuan Wen Huang 《World Journal of Clinical Cases》 SCIE 2025年第2期50-58,共9页
BACKGROUND Autologous fat injection in facial reconstruction is a common cosmetic surgery.Although cerebral fat embolism(CFE)as a complication is rare,it carries serious health risks.CASE SUMMARY We present a case of ... BACKGROUND Autologous fat injection in facial reconstruction is a common cosmetic surgery.Although cerebral fat embolism(CFE)as a complication is rare,it carries serious health risks.CASE SUMMARY We present a case of a 29-year-old female patient who developed acute CFE following facial fat filling surgery.After the surgery,the patient experienced symptoms including headache,nausea,vomiting,and difficulty breathing,which was followed by neurological symptoms such as slurred speech and left-sided weakness.Comprehensive physical examination and auxiliary investigations,including blood tests,head and neck computed tomography angiography,and cranial magnetic resonance diffusion-weighted imaging,were performed upon admission.The clinical diagnosis was acute cerebral embolism following facial fat filling surgery.Treatment included measures to improve cerebral circulation,dehydration for intracranial pressure reduction,nutritional support,and rehabilitation therapy for left limb function.The patient showed a significant improvement in symptoms after 2 weeks of treatment.She recovered left limb muscle strength to grade 5,had clear speech,and experienced complete relief of headache.CONCLUSION Our case highlights the potential occurrence of severe complications in patients undergoing fat injection in facial reconstruction.To prevent these complications,plastic surgeons should enhance their professional knowledge and skills. 展开更多
关键词 Cerebral fat embolism Mechanical thrombectomy THROMBOLYSIS Steroid therapy Symptomatic treatment Case report
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Refractory lipoatrophy treated with autologous whole blood injection:A case report
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作者 Wonnam Kim Jun Su Park En Hyung Kim 《World Journal of Clinical Cases》 SCIE 2025年第2期33-38,共6页
BACKGROUND Intramuscular corticosteroid injection may cause adverse effects such as dermal and/or subcutaneous atrophy,alopecia,hypopigmentation,and hyperpigmentation.Although cutaneous atrophy can spontaneously resol... BACKGROUND Intramuscular corticosteroid injection may cause adverse effects such as dermal and/or subcutaneous atrophy,alopecia,hypopigmentation,and hyperpigmentation.Although cutaneous atrophy can spontaneously resolve,several treatment options have been suggested for this condition.CASE SUMMARY In this paper,we report a case of corticosteroid injection induced lipoatrophy treated with autologous whole blood(AWB)injection,as the condition had been unresponsive to fractional laser therapy.A 29-year-old female patient visited the dermatology clinic complaining of skin depression on her right buttock area,which had appeared six months earlier.There had been only subtle improvement at the margins after fractional CO2 laser treatment;therefore,after obtaining informed consent from the patient,AWB treatment was initiated.One month after the first AWB injection,the size and depth of the lesion had noticeably improved,and a slight improvement was also observed in discoloration.CONCLUSION Close observation is the initial treatment of choice for steroid induced skin atrophy;however,for patients in need of immediate cosmetic improvement,AWB injection may be a safe and cost-effective alternative. 展开更多
关键词 ATROPHY CORTICOSTEROID Subcutaneous fat Autologous whole blood injection Laser therapy Case report
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Primary parenchymal squamous cell carcinoma of the kidney:A case report
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作者 Zhi-Hui Zheng Bo Shao +4 位作者 Chao-Min Xu Ke Wang Jia-Zhu Wen Li-Kang Luo Jia-Cheng Guan 《World Journal of Clinical Cases》 SCIE 2025年第4期34-40,共7页
BACKGROUND Primary squamous cell carcinoma(SCC)of the renal parenchyma is extremely rare,with only nine cases reported.CASE SUMMARY This study reports a 51-year-old man with primary SCC of the renal parenchyma.The pat... BACKGROUND Primary squamous cell carcinoma(SCC)of the renal parenchyma is extremely rare,with only nine cases reported.CASE SUMMARY This study reports a 51-year-old man with primary SCC of the renal parenchyma.The patient was admitted with recurrent dull pain and discomfort in the right lumbar region,which had worsened over 2 weeks,accompanied by painful gross hematuria.SCC antigen(SCCA)levels were elevated,and imaging revealed a renal mass with associated calculi.The patient underwent laparoscopic unilateral nephrectomy and lymph node dissection.Postoperative pathology confirmed highly differentiated SCC with necrosis in the right renal parenchyma,with negative renal pelvis and ureter.The pathological stage was Pt3aN1M0.Four months after surgery,the tumor recurred with involvement of the liver,right psoas major muscle,and inferior vena cava.The patient refused chemotherapy and succumbed to the disease 6 months postoperatively due to disease progression.CONCLUSION We report a case of primary SCC of the renal parenchyma,a rare renal malignancy.The clinical symptoms,laboratory tests,and imaging findings are nonspecific,making accurate and timely diagnosis challenging.According to the literature,for patients with renal calculi accompanied by a renal mass,elevated serum SCCA levels,and magnetic resonance imaging showing cystic or cystic-solid masses within the kidney with pseudocapsules and heterogeneous mild enhancement,the possibility of this disease should be considered. 展开更多
关键词 Renal tumor Renal parenchyma Squamous cell carcinoma Renal calculi Computed tomography Case report
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Pulp health and calcific healing of a complicated crown–root fracture with additional root fracture in a maxillary incisor: A case report
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作者 Na Li Yue-Yue Ren +4 位作者 Ying Tang Qi Yang Tian-Tian Meng Song Li Jing Zhang 《World Journal of Clinical Cases》 SCIE 2025年第3期42-49,共8页
BACKGROUND Complicated crown–root fracture (CRF) involves severe injury to the crown, root,and pulp, and may be accompanied by multiple root fractures. The loss of a toothhas lifelong consequences for children and te... BACKGROUND Complicated crown–root fracture (CRF) involves severe injury to the crown, root,and pulp, and may be accompanied by multiple root fractures. The loss of a toothhas lifelong consequences for children and teenagers, but the maintenance of pulphealth and the calcific healing of multiple root fractures are rarely reported in theliterature.CASE SUMMARY This case reports healing of a permanent tooth with complicated crown–root andadditional root fractures, in which pulp health was maintained. A 10-year-old girlfell and fractured the root of her maxillary left central incisor at the cervical level.After the coronal fragment was repositioned, the tooth was splinted until thetooth was no longer mobile, 2 years later. Eight years after treatment, the toothhas remained asymptomatic with vital pulp and localized gingival overgrowth.Cone-beam computed tomography revealed not only calcified healing of the CRFbut also spontaneous healing in an additional undiagnosed root fracture. Thefracture line on the enamel could not be healed by hard tissue and formed agroove in the cervical crown. It was speculated that the groove was related to thelocalized gingival overgrowth.CONCLUSION This case provides a clinical perspective of the treatment of a tooth with acomplicated CRF and an additional root fracture. 展开更多
关键词 Complicated crown-root fracture Multiple root fracture Spontaneous healing Cone-beam computed tomography Long-term follow-up Case report
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Pan-TRK positive uterine sarcoma in immunohistochemistry without neurotrophic tyrosine receptor kinase gene fusions:A case report
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作者 Seungmee Lee Yu-Ra Jeon +2 位作者 Changmin Shin Sun-Young Kwon Sojin Shin 《World Journal of Clinical Cases》 SCIE 2025年第2期39-49,共11页
BACKGROUND The classification of uterine sarcomas is based on distinctive morphological and immunophenotypic characteristics,increasingly supported by molecular genetic diagnostics.Data on neurotrophic tyrosine recept... BACKGROUND The classification of uterine sarcomas is based on distinctive morphological and immunophenotypic characteristics,increasingly supported by molecular genetic diagnostics.Data on neurotrophic tyrosine receptor kinase(NTRK)gene fusionpositive uterine sarcoma,potentially aggressive and morphologically similar to fibrosarcoma,are limited due to its recent recognition.Pan-TRK immunohistochemistry(IHC)analysis serves as an effective screening tool with high sensitivity and specificity for NTRK-fusion malignancies.CASE SUMMARY We report a case of a malignant mesenchymal tumor originating from the uterine cervix,which was pan-TRK IHC-positive but lacked NTRK gene fusions,accompanied by a brief literature review.A 55-year-old woman presented to the emergency department with abdominal pain and distension,exhibiting significant ascites and multiple solid pelvic masses.Pelvic examination revealed a tumor encompassing the uterine cervix,extending to the vagina and uterine corpus.A punch biopsy of the cervix indicated NTRK sarcoma with positive immunochemical pan-TRK stain.However,subsequent next generation sequencing revealed no NTRK gene fusion,leading to a diagnosis of poorly differentiated,advanced-stage sarcoma.CONCLUSION The clinical significance of NTRK gene fusion lies in potential treatment with TRK inhibitors for positive sarcomas.Identifying such rare tumors is crucial due to the potential applicability of tropomyosin receptor kinase inhibitor treatment. 展开更多
关键词 Uterine sarcoma Cervical sarcoma Neurotrophic tyrosine receptor kinase gene fusion Next generation sequencing Case report
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Successful emergency surgical intervention in acute non-STsegment elevation myocardial infarction with rupture:A case report
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作者 Xing-Po Li Zi-Shan Wang +1 位作者 Hong-Xia Yu Shan-Shan Wang 《World Journal of Clinical Cases》 SCIE 2025年第4期41-47,共7页
BACKGROUND The incidence of acute myocardial infarction(AMI)is rising,with cardiac rupture accounting for approximately 2%of deaths in patients with acute ST-segment elevation myocardial infarction(STEMI).Ventricular ... BACKGROUND The incidence of acute myocardial infarction(AMI)is rising,with cardiac rupture accounting for approximately 2%of deaths in patients with acute ST-segment elevation myocardial infarction(STEMI).Ventricular free wall rupture(FWR)occurs in approximately 2%of AMI patients and is notably rare in patients with non-STEMI.Types of cardiac rupture include left ventricular FWR,ventricular septal rupture,and papillary muscle rupture.The FWR usually leads to acute cardiac tamponade or electromechanical dissociation,where standard resuscitation efforts may not be effective.Ventricular septal rupture and papillary muscle rupture often result in refractory heart failure,with mortality rates over 50%,even with surgical or percutaneous repair options.CASE SUMMARY We present a rare case of an acute non-STEMI patient who suffered sudden FWR causing cardiac tamponade and loss of consciousness immediate before undergoing coronary angiography.Prompt resuscitation and emergency open-heart repair along with coronary artery bypass grafting resulted in successful patient recovery.CONCLUSION This case emphasizes the risks of AMI complications,shares a successful treatment scenario,and discusses measures to prevent such complications. 展开更多
关键词 Acute non-ST segment elevation myocardial infarction Cardiac rupture Acute myocardial infarction Free wall rupture Case report
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Stage IV malignant transformation of mature cystic teratoma palliatively treated with concurrent chemoradiotherapy:A case report
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作者 Saori Kondo Takashi Suzuki +4 位作者 Kanato Yoshiike Sakura Yamanaka Kenta Sonehara Hiroshi Nabeshima Osamu Oguchi 《World Journal of Clinical Cases》 SCIE 2025年第1期56-61,共6页
BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a ... BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a case in which CCRT had a reduction effect preoperatively.A 73-year-old woman with pyelonephritis was referred to our hospital.Computed tomography revealed right hydronephrosis and a 6-cm pelvic mass.Endoscopic ultrasound-guided fine-needle biopsy(EUS-FNB)revealed squamous cell carci-noma.The patient was diagnosed with MT of MCT.Due to her poor general con-dition and renal malfunction,we selected CCRT,expecting fewer adverse effects.After CCRT,her performance status improved,and the tumor size was reduced;surgery was performed.Five months postoperatively,the patient developed dis-semination and lymph node metastases.Palliative chemotherapy was ineffective.She died 18 months after treatment initiation.CONCLUSION EUS-FNB was useful in the diagnosis of MT of MCT;CCRT suppressed the disea-se and improved quality of life. 展开更多
关键词 Mature cystic teratoma Malignant transformation Squamous cell carcinoma Concurrent chemoradiotherapy Endoscopic ultrasound-guided fine-needle biopsy Case report
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Brachioradialis tendon transfer and palmaris longus tendon graft for thumb avulsion:A case report and review of literature
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作者 Pierre Curings Sonia Ramos-Pascual +4 位作者 Kinga Michalewska Nicolas Gibert Lionel Erhard Mo Saffarini AlexisNogier 《World Journal of Clinical Cases》 SCIE 2025年第4期48-55,共8页
BACKGROUND Thumb replantation following complete traumatic avulsion requires complex techniques to restore function,especially in cases of avulsion at the level of the metacarpophalangeal joint(MCP I)and avulsion of t... BACKGROUND Thumb replantation following complete traumatic avulsion requires complex techniques to restore function,especially in cases of avulsion at the level of the metacarpophalangeal joint(MCP I)and avulsion of the flexor pollicis longus(FPL)at the musculotendinous junction.Possible treatments include direct tendon suture or tendon transfer,most commonly from the ring finger.To optimize function and avoid donor finger complications,we performed thumb replantation with flexion restoration using brachioradialis(BR)tendon transfer with palmaris longus(PL)tendon graft.CASE SUMMARY A 20-year-old left-handed male was admitted for a complete traumatic left thumb amputation following an accident while sliding from the top of a handrail.The patient presented with skin and bone avulsion at the MCP I,avulsion of the FPL tendon at the musculotendinous junction(zone 5),avulsion of the extensor pollicis longus tendon(zone T3),and avulsion of the thumb’s collateral arteries and nerves.The patient was treated with two stage thumb repair.The first intervention consisted of thumb replantation with MCP I arthrodesis,resection of avulsed FPL tendon and implantation of a silicone tendon prosthesis.The second intervention consisted of PL tendon graft and BR tendon transfer.Follow-up at 10 months showed good outcomes with active interphalangeal flexion of 70°,grip strength of 45 kg,key pinch strength of 15 kg and two-point discrimination threshold of 4 mm.CONCLUSION Flexion restoration after complete thumb amputation with FPL avulsion at the musculotendinous junction can be achieved using BR tendon transfer with PL tendon graft. 展开更多
关键词 Brachioradialis tendon transfer Flexor pollicis longus Palmaris longus tendon graft REPLANTATION Thumb amputation Thumb avulsion Case report
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Calculation of Agricultural Production Efficiency Based on a Three-stage Data Envelopment Analysis Model and Analysis of the Spatial-temporal Characteristics: A Case Study of the Yangtze River Economic Belt
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作者 Wenjun ZHUO Haiyang CUI 《Meteorological and Environmental Research》 CAS 2021年第5期68-76,83,共10页
In response to the strategic call for the " Great Protection" of the Yangtze River Economic Belt and to fulfill the important historical tasks assigned by the state to the provinces and cities of the area,th... In response to the strategic call for the " Great Protection" of the Yangtze River Economic Belt and to fulfill the important historical tasks assigned by the state to the provinces and cities of the area,the Yangtze River Economic Belt is adjusting the agricultural industry structure,optimizing the input-output ratio,and ensuring stable and sustainable agricultural production. Based on the combination of the three-stage Data Envelopment Analysis( DEA) model and cluster analysis,this study examined the Yangtze River Economic Belt from 2008 to 2018 to measure its agricultural production efficiency and to analyze its temporal and spatial characteristics. Studies showed that exogenous environmental factors significantly( P < 5%) impacted agricultural production efficiency in the Yangtze River Economic Zone,and there were temporal and spatial differences. These included:(1) after excluding environmental factors,the overall agricultural production efficiency of the Yangtze River Economic Zone had improved. Sichuan Province and Jiangsu Province were at the forefront of efficiency,whereas the agricultural production efficiency of Shanghai had declined obviously.(2) The agricultural production efficiency of the Yangtze River Economic Belt varied year by year,with fluctuating development. The middle reaches of the Yangtze River had advanced agricultural production efficiency more than the upstream and downstream regions,and the agricultural production efficiency of the individual provinces did not match their economic and social development.(3) Increases in labor,land,irrigation,and other input factors increased agriculture production efficiency,and there was no correlation between fiscal investment,per capita gross domestic product( GDP) and agricultural production efficiency,while the disaster-affected area had a significantly negative impact on agricultural production efficiency. 展开更多
关键词 Agricultural production efficiency three-stage Date Envelopment Analysis Temporal and spatial characteristics Yangtze River Economic Belt
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Estimating regional coal resource efficiency in China using three-stage DEA and bootstrap DEA models 被引量:10
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作者 Cui Yijia Huang Guoliang Yin Ziyong 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第5期861-864,共4页
Based on three-stage data envelopment analysis(DEA) model estimates of resource utilization efficiency of coal,we selected 29 provinces from China's 2012 input-output data and used the bootstrap DEA model to corre... Based on three-stage data envelopment analysis(DEA) model estimates of resource utilization efficiency of coal,we selected 29 provinces from China's 2012 input-output data and used the bootstrap DEA model to correct the bias.The results show that the mean overall technical efficiency,pure technical efficiency,and scale efficiency was 0.833,0.998,and 0.711 in 2012,respectively.Moreover,the comprehensive technical efficiency score indicates that the scale is invalid.Area utilization efficiencies for the eastern,central,and western regions were 0.917,0.731,and 0.629,respectively.The results prove that there are significant differences in the distribution of coal resources utilization efficiency across regions. 展开更多
关键词 Coal resource efficiency three-stage DEA Bootstrap DEA Technical efficiency
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Investigation on seismic response of a three-stage soil slope supported by anchor frame structure 被引量:5
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作者 LIN Yu-liang LI Ying-xin +1 位作者 ZHAO Lian-heng YANG T Y 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第4期1290-1305,共16页
Based on a typical prototype of a soil slope in engineering practice, a numerical model of a three-stage soil slope supported by the anchor frame structure was established by means of FLAC3D code. The dynamic response... Based on a typical prototype of a soil slope in engineering practice, a numerical model of a three-stage soil slope supported by the anchor frame structure was established by means of FLAC3D code. The dynamic responses of three-stage soil slope and frame structure were studied by performing a series of bidirectional Wenchuan motions in terms of the failure mode of three-stage structure, the acceleration of soil slope, the displacement of frame structure, and the anchor stress of frame structure. The response accelerations in both horizontal and vertical directions are the most largely amplified at the slope top of each stage subjected to different shaking cases. The platforms among the stages reduce the amplification effect of response acceleration. The residual displacement of frame structure increases significantly as the intensity of shaking case increases. The frame structure at each stage presents a combined displacement mode consisting of a translation and a rotation around the vertex. The anchor stress of frame structure is mainly increased by the first intense pulse of Wenchuan seismic wave, and it is sensitive to the intensity of shaking case. The anchor stress of frame structure at the first stage is the most considerably enlarged by earthquake loading. 展开更多
关键词 three-stage soil slope anchor frame structure ACCELERATION DISPLACEMENT anchor stress
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Production Efficiency of Two-Oriented Agriculture Based on Three-Stage DEA Model 被引量:10
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作者 ZHAI Huan-huan HE Zheng-chu ZHANG Rui 《Agricultural Science & Technology》 CAS 2010年第4期159-163,共5页
Two-oriented agriculture was a complex organism coupling production,economics,society and ecology.Its development process was affected by various factors such as producers,nature,society,etc.In order to overcome measu... Two-oriented agriculture was a complex organism coupling production,economics,society and ecology.Its development process was affected by various factors such as producers,nature,society,etc.In order to overcome measurement error of traditional data envelopment analysis caused by ignoring random,three-stage DEA model was studied to remove environmental factors and random effects.On the foundation of this model was two-oriented agriculture comprehensive production efficiency of 14 cities were estimated in Hunan Province in 2008,and brown forth corresponding policy proposals to promote agricultural development. 展开更多
关键词 Two-oriented agriculture three-stage DEA model Technical efficiency Scale efficiency
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An Analysis of Operational Efficiency of Agricultural Insurance Agency:Based on Three-Stage DEA Model 被引量:2
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作者 Xuan CHEN Wenhuan WEI 《Asian Agricultural Research》 2016年第12期12-16,共5页
From the perspective of agricultural insurance agency,this paper focuses on the study of operational efficiency of agricultural insurance agency,and analyzes the operational efficiency of agricultural insurance agency... From the perspective of agricultural insurance agency,this paper focuses on the study of operational efficiency of agricultural insurance agency,and analyzes the operational efficiency of agricultural insurance agency and its influencing factors,in order to improve the operational efficiency of agricultural insurance agency,better supply agricultural insurance and achieve the policy effect of agricultural insurance.The results of this paper are as follows:( i) Either comprehensive operational efficiency or scale efficiency of Chinese-funded agency is higher than that of foreign-funded agency,but its pure technical efficiency is lower than that of foreign-funded agency,indicating that the managerial decision ability of Chinese-funded agency is weaker than that of foreign-funded agency,and needs to be improved;( ii) The operational efficiency of professional agricultural insurance agency is higher than that of comprehensive agricultural insurance agency,and the agricultural insurance agency is greatly affected by environmental factors;( iii) The operating time of agricultural insurance agency is proportional to its operational efficiency;( iv) The quality of employees is positively correlated with the capital and cost input difference,but negatively correlated with the difference in the number of employees. Therefore,it is necessary to pay attention to the improvement of employees' working efficiency while laying emphasis on employees' quality. 展开更多
关键词 three-stage DEA Operational efficiency Influencing factors
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Contribution to the Optimization of the Transient Stability of an Electric Power Transmission Network Using a Universal Power Flow Compensator Controlled by a Three-Stage Inverter 被引量:2
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作者 Koko Koko Joseph Nneme Nneme Léandre Ndjakomo Essiane Salomé 《World Journal of Engineering and Technology》 2020年第4期675-688,共14页
The use of an electrical network as close as possible to its limits can lead to its instability in the event of a high amplitude disturbance. The damping of system oscillations can be achieved by conventional means of... The use of an electrical network as close as possible to its limits can lead to its instability in the event of a high amplitude disturbance. The damping of system oscillations can be achieved by conventional means of voltage and speed regulation but also by FACTS (Flexible AC Transmission Systems) devices, which are increasingly used in power networks. In this work, optimal control coordination between a hybrid power flow controller and a three-level inverter was used to improve the transient stability of a transmission line. The UPFC is a combination of a serial compensator (SSSC) and a parallel compensator (STATCOM) both connected to a DC-LINK DC bus. The SSSC acts as a voltage source for the network and injects a voltage that can be adjusted in phase and amplitude in addition to the network voltage;the STATCOM acts as a current source. The approach used is tested in the Matlab Simulink environment on a single machine network. Optimal controller tuning gives a better transient stability improvement by reducing the transport angle oscillations from 248.17% to 9.85%. 展开更多
关键词 FACTS UPFC three-stage Inverter PI Power Transit Transient Stability
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Improving Bandwidth of Three-Stage Electro-Hydraulic Servo Valve Based on Speed-Feedback 被引量:1
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作者 刘小初 何景峰 +2 位作者 叶正茂 丛大成 韩俊伟 《Journal of Donghua University(English Edition)》 EI CAS 2009年第5期494-498,共5页
In order to improve the dynamic response bandwidth of three-stage electro-hydraulic servo valve,a new method,speed-feedback control is presented in this paper.The construction and principle of three-stage electro-hydr... In order to improve the dynamic response bandwidth of three-stage electro-hydraulic servo valve,a new method,speed-feedback control is presented in this paper.The construction and principle of three-stage electro-hydraulic servo valve are explained,and the mathematical model of three-stage electro-hydraulic servo valve is built in frequency domain.Experimental and simulation results show that the bandwidth compared with proportional control is improved under speed-feedback control.Moreover,the research results play an important role in developing high performance three-stage electro-hydraulic servo valve. 展开更多
关键词 three-stage electro-hydraulic serw walve BANDWIDTH speed-feedback construction PRINCIPLE model simulation experimental test
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Numerical Simulation of Enhanced Oil-Water Separation in a Three-Stage Double-Stirring Extraction Tank 被引量:3
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作者 Lü Chao Zhang Zimu +3 位作者 Zhao Qiuyue Wang Shuchan Zhang Ting'an Liu Yan 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第4期121-126,共6页
Numerical simulation of enhanced fluid flow characteristics in a three-stage double-stirring extraction tank was conducted with the coupling of an Eulerian multiphase flow model and a Morsi-Alexander interphase drag f... Numerical simulation of enhanced fluid flow characteristics in a three-stage double-stirring extraction tank was conducted with the coupling of an Eulerian multiphase flow model and a Morsi-Alexander interphase drag force model. Results show that the addition of a stirring device into the settler can efficiently reduce the volume fraction of out-of-phase impurity in the outlet, and accelerate the settling separation of oil-water mixture. Such addition can also effectively break down the oil-water-wrapped liquid droplets coming from the mixer, inhibit reflux from the outlet, and improve the oil-water separation. The addition of a stirring device induces ignorable power consumption compared with that by the mixer, and can thus facilitate the commercialized promotion of this novel equipment. 展开更多
关键词 three-stage extraction tank double-stirring numerical simulation flow characteristics power
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