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Biliary hemorrhage caused by a malignant small round cell tumor in the common bile duct:A case report
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作者 Ying-Li Jin Ye-Jiao Ruan Guang-Rong Lu 《World Journal of Clinical Cases》 SCIE 2023年第31期7706-7711,共6页
BACKGROUND Malignant small round cell tumor(MSRCT)metastasis to the common bile duct associated with recurrent biliary hemorrhage is extremely rare.Thus far,there have been no reports of metastatic small round cell tu... BACKGROUND Malignant small round cell tumor(MSRCT)metastasis to the common bile duct associated with recurrent biliary hemorrhage is extremely rare.Thus far,there have been no reports of metastatic small round cell tumors of the common bile duct.CASE SUMMARY Herein,we report the case of a 77-year-old female patient with an MSRCT in the common bile duct.The patient was admitted to hospital due to gastrointestinal hemorrhage and abdominal pain.We found a neoplasm in the common bile duct with active bleeding through a spyglass.We performed biopsy through the spyglass and placed a metal stent to stop bleeding.The pathological result suggested that it was an MSRCT metastasized from the back to the common bile duct.Later,we found using fluorescence in situ hybridization that the SS18 gene break test was negative,ruling out the diagnosis of synovial sarcoma.CONCLUSION MSRCT is a group of tumors with similar cell morphology and diffuse histological structure.Complete tumor resection results in improved survival in patients with MSRCT.Roux-en-Y cholangiojejunostomy was performed.After excision of the common bile duct tumor,the patient felt that the abdominal pain improved and hemorrhage disappeared.The patient underwent routine fecal examination one month after surgery,indicating a negative fecal occult blood test.On May 22,2023,the patient was reexamined by abdominal computed tomography,and no abdominal space occupying lesions or abdominal lymphadenopathy was found. 展开更多
关键词 Common bile duct metastasis HEMORRHAGE Recurrent biliary hemorrhage Malignant small round cell tumor SpyGlass Case report
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Combined resection and multi-agent adjuvant chemotherapy for desmoplastic small round cell tumor arising in the abdominal cavity:Report of a case 被引量:104
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作者 Chang-Cheng Chang Jun-Te Hsu +3 位作者 Jeng-Hwei Tseng Tsann-Long Hwang Han-Ming Chen Yi-Yin Jan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第5期800-803,共4页
Desmoplastic small round cell tumor (DSRCT) is a rare, highly aggressive malignancy with distinctive histological features: a nesting pattern of cellular growth within dense desmoplastic stroma, occurring in young ... Desmoplastic small round cell tumor (DSRCT) is a rare, highly aggressive malignancy with distinctive histological features: a nesting pattern of cellular growth within dense desmoplastic stroma, occurring in young population with male predominance. The mean survival period is only about 1.5-2.5 years. The tumor has co-expressed epithelial, muscle, and neural markers in immunohistochemical studies. This work reports a 27-year-old man presenting with hematemesis and chronic constipation. Serial studies including endoscopy, upper gastrointestinal series, abdominal computed tomography and barium enema study showed disseminated involvement of visceral organs. The patient underwent aggressive surgery and received postoperative adjuvant chemotherapy consisting of 5-fluorouracil, cyclophosphamide, etoposide, doxorubicin, and cisplatin. He survived without any disease for 20 mo after the surgery. No standard treatment protocol has been established. Aggressive surgery combined with postoperative multi-agent adjuvant chemotherapy is justified not only to relieve symptoms but also to try to improve the outcome in this advanced DSRCT young patient. 展开更多
关键词 Desmoplastic small round cell tumor Surgery Chemotherapy
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Clinical and computed tomography features of adult abdominopelvic desmoplastic small round cell tumor 被引量:5
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作者 Xun-Ze Shen Jian-Guo Zhao +1 位作者 Jian-Jun Wu Fang Liu 《World Journal of Gastroenterology》 SCIE CAS 2014年第17期5157-5164,共8页
To investigate the clinical and computed tomography(CT)features of desmoplastic small round cell tumor(DSRCT),we retrospectively analyzed the clinical presentations,treatment and outcome,as well as CT manifestations o... To investigate the clinical and computed tomography(CT)features of desmoplastic small round cell tumor(DSRCT),we retrospectively analyzed the clinical presentations,treatment and outcome,as well as CT manifestations of four cases of DSRCT confirmed by surgery and pathology.The CT manifestations of DSRCT were as follows:(1)multiple soft-tissue masses or diffuse peritoneal thickening in the abdomen and pelvis,with the dominant mass usually located in the pelvic cavity;(2)masses without an apparent organbased primary site;(3)mild to moderate homogeneous or heterogeneous enhancement in solid area on enhanced CT;and(4)secondary manifestations,such as ascites,hepatic metastases,lymphadenopathy,hydronephrosis and hydroureter.The prognosis and overall survival rates were generally poor.Commonly used treatment strategies including aggressive tumor resection,polychemotherapy,and radiotherapy,showed various therapeutic effects.CT of DSRCT shows characteristic features that are helpful in diagnosis.Early discovery and complete resection,coupled with postoperative adjuvant chemotherapy,are important for prognosis of DSRCT.Whole abdominopelvic rather than locoregional radiotherapy is more effective for unresectable DSRCT. 展开更多
关键词 Desmoplastic small round cell tumor PERITONEUM PATHOLOGY Computed tomography Clinical features
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Retroperitoneal desmoplastic small round cell tumor:Pediatric patient treated with multimodal therapy 被引量:4
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作者 Yong Seok Kim Seong Jae Cha +3 位作者 Yoo Shin Choi Beom Gyu Kim Sung Jun Park In Taik Chang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第33期4212-4214,共3页
A desmoplastic small round cell tumor (DSRCT) is a rare, aggressive mesenchymal neoplasm. Although a DSRCT can develop at various sites, the intraabdominal site is the most common location. These tumors are found most... A desmoplastic small round cell tumor (DSRCT) is a rare, aggressive mesenchymal neoplasm. Although a DSRCT can develop at various sites, the intraabdominal site is the most common location. These tumors are found most commonly among young adolescents and the prognosis is extremely poor. Multimodal treatment with surgery, chemotherapy and radiotherapy is very important for these rare cases, and this treatment can improve patient survival. In this report, we describe the case of an 8-year-old boy diagnosed with DSRCT located in the retroperitoneal space. The patient has undergone surgical resection and adjuvant chemoradiation therapy, and is currently alive without disease recurrence. 展开更多
关键词 RETROPERITONEUM Desmoplastic small round cell tumor Multimodal therapy
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Desmoplastic small round cell tumor with atypical immunohistochemical profile and rhabdoid-like differentiation 被引量:1
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作者 Li Liang Nina Tatevian +2 位作者 Meenakshi Bhattacharjee Kuojen Tsao John Hicks 《World Journal of Clinical Cases》 SCIE 2014年第8期367-372,共6页
Desmoplastic small round cell tumor(DSRCT) is a rare,aggressive malignant neoplasm of unknown origin, and is comprised of small round cells with a characteristic desmoplastic stroma. DSRCT typically expresses epitheli... Desmoplastic small round cell tumor(DSRCT) is a rare,aggressive malignant neoplasm of unknown origin, and is comprised of small round cells with a characteristic desmoplastic stroma. DSRCT typically expresses epithelial, mesenchymal and neural markers simultaneously. We describe a case of DSRCT with an atypical immunohistochemical profile and rhabdoid-like tumor cells on electron microscopy. In the present case, the neoplastic cells were positive only for vimentin, desmin(cytoplasmic membranous pattern) and CD56,and negative for smooth muscle actin, synaptophysin,CD117, CD45, myogenin, CAM5.2, pancytokeratin,WT1, EMA, CD99, neurofilament, CD34 and p53. Ki67 showed a low proliferative activity. Electron microscopy showed focal rhabdoid differentiation. However, INI-1(SNF-5/BAF47) demonstrated preservation of nuclear positivity in the neoplastic cells. Cytogenetic studies showed translocation t(11;22)(p13;q12) confirming an EWSR1-WT1 translocation characteristic for DSRCT, and t(1;15)(q11;p11.2) of unknown significance. This case is a diagnostic challenge because of atypical immunohistochemical profile and cytogenetic study is crucial in rendering the correct diagnosis. 展开更多
关键词 DESMOPLASTIC small round cell tumor ULTRASTRUCTURE CYTOGENETICS RHABDOID cells EWSR1-WT1
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Desmoplastic small round cell tumor of the abdomen: A case report and literature review of therapeutic options
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作者 Hafida Benhammane Leila Chbani +5 位作者 Abdelmalek Ousadden Ouadii Mouquit Siham Tizniti Afaf Riffi Amarti Nouafal Mellas Omar El Mesbahi 《Health》 2012年第4期207-211,共5页
Desmoplastic small round cell tumor (DSRCT) is a rare and highly aggressive variety of sarcoma arising typically from abdominal or pelvic peritoneum. Diagnosis and treatment approaches of this entity are complex and r... Desmoplastic small round cell tumor (DSRCT) is a rare and highly aggressive variety of sarcoma arising typically from abdominal or pelvic peritoneum. Diagnosis and treatment approaches of this entity are complex and require a skilled, experienced, multidisciplinary team. Authors report their experience with a case of an intraabdominal DSRCT arising in a 37-year-old young man in order to discuss the clinico-pathological and radiological behavior of this tumor and underline diagnostic and therapeutic difficulties. 展开更多
关键词 DESMOPLASTIC small round Cell Tumor ABDOMEN HISTOLOGY CHEMOTHERAPY Surgery OUTCOME
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Ovarian desmoplastic small round cell tumors: Prognosis is poor! Case report
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作者 Hanane Saadi Hind Fatmi +4 位作者 Nissrine Mamouni Sanaa Errarhay Chahrazed Bouchikhi Afaf Amarti Abdelaziz Banani 《Open Journal of Obstetrics and Gynecology》 2013年第2期235-238,共4页
The tumor desmoplastic small round cell in women is rare. Ovarian its location is exceptional. We report a patient of 20 years, the originalNorth Africawho consulted for an increase in abdominal volume with impaired g... The tumor desmoplastic small round cell in women is rare. Ovarian its location is exceptional. We report a patient of 20 years, the originalNorth Africawho consulted for an increase in abdominal volume with impaired general condition. Pelvic ultrasonography and computed tomography were in favor of multiple peritoneal masses with ascites. After surgical exploration, the histological and immunohistochemical data for diagnosis small round cell desmoplastic tumor of ovarian the patient was a candidate for poly chemotherapy but she was died a month later. Diagnosis relies on histological and immunohistochemical data. The demonstration of a nonrandom translocation t (11;22) (p13;q12) is specific for the disease. The management is multidisciplinary and combining surgery, a poly aggressive chemotherapy and radiotherapy. The prognosis remains poor. 展开更多
关键词 small round Cell DESMOPLASTIC TUMOR OVARIAN Diagnosis Treatment PROGNOSIS
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基于MobileNetV3Small-ECA的水稻病害轻量级识别研究 被引量:5
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作者 袁培森 欧阳柳江 +1 位作者 翟肇裕 田永超 《农业机械学报》 EI CAS CSCD 北大核心 2024年第1期253-262,共10页
为实现水稻病害的轻量化识别与检测,使用ECA注意力机制改进MobileNetV3Small模型,并使用共享参数迁移学习对水稻病害进行智能化轻量级识别和检测。在PlantVillage数据集上进行预训练,将预训练得到的共享参数迁移到对水稻病害识别模型上... 为实现水稻病害的轻量化识别与检测,使用ECA注意力机制改进MobileNetV3Small模型,并使用共享参数迁移学习对水稻病害进行智能化轻量级识别和检测。在PlantVillage数据集上进行预训练,将预训练得到的共享参数迁移到对水稻病害识别模型上微调优化。在开源水稻病害数据集上进行试验测试,试验结果表明,在非迁移学习下,识别准确率达到97.47%,在迁移学习下识别准确率达到99.92%,同时参数量减少26.69%。其次,通过Grad-CAM进行可视化,本文方法与其他注意力机制CBAM和SENET相比,ECA模块生成的结果与图像中病斑的位置和颜色更加一致,表明网络可以更好地聚焦水稻病害的特征,并且通过可视化和各水稻病害分析了误分类原因。本文方法实现了水稻病害识别模型的轻量化,使其能够在移动设备等资源受限的场景中部署,达到快速、高效、便携的目的。同时开发了基于Android的水稻病害识别系统,方便于在边缘端进行水稻病害识别分析。 展开更多
关键词 水稻病害识别 迁移学习 高效通道注意力机制 MobileNetV3small 移动端部署
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miRNA对褐飞虱鞘脂质代谢基因表达的影响及沉默NlSPT1和Nl SMase4的small RNA分析
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作者 王妮 施哲逸 +4 位作者 尤元政 张超 周文武 周瀛 祝增荣 《中国农业科学》 CAS CSCD 北大核心 2024年第20期4022-4034,共13页
【背景】鞘脂质是第二大类膜脂,作为信号转导物质参与细胞生长发育、繁殖及凋亡等过程。鞘脂质代谢酶调控鞘脂质代谢以维持生物体内代谢的稳态。【目的】以重要水稻害虫褐飞虱(Nilaparvata lugens)为研究对象,通过RNA干扰(RNA interfere... 【背景】鞘脂质是第二大类膜脂,作为信号转导物质参与细胞生长发育、繁殖及凋亡等过程。鞘脂质代谢酶调控鞘脂质代谢以维持生物体内代谢的稳态。【目的】以重要水稻害虫褐飞虱(Nilaparvata lugens)为研究对象,通过RNA干扰(RNA interference,RNAi)技术检测微小RNA(microRNA,miRNA)生物合成通路核心组分NlAgo1、NlDicer1和NlDrosha沉默后褐飞虱鞘脂质代谢通路相关基因的相对转录水平,结合small RNA测序分析沉默丝氨酸棕榈酰转移酶1(serine palmitoyltransferase 1,SPT1)和鞘磷脂酶4(sphingomyelinase 4,SMase4)基因的差异miRNA,探究miRNA在褐飞虱鞘脂质代谢中的作用,为害虫防治提供新的分子靶标。【方法】利用RNAi技术,分别对羽化后第1天(1 PAE,post adult eclosion)的雌成虫NlAgo1、NlDicer1和NlDrosha进行dsRNA注射,以ds GFP为对照;分别解剖羽化后第5天的卵巢组织,以β-actin作为内参基因,采用实时荧光定量PCR(qRT-PCR)方法检测NlAgo1、NlDicer1和NlDrosha沉默后鞘脂质代谢通路相关基因的表达量变化;根据已有的小RNA文库联合miRNA-靶基因预测软件对可能调控NlSPT1和NlSMase4表达的miRNA进行预测;通过small RNA测序技术对沉默NlSPT1和NlSMase4的差异miRNA进行鉴定和靶基因富集性分析。【结果】与对照组相比,沉默NlAgo1、NlDicer1或NlDrosha显著上调卵巢中NlSPT1和NlSMase4等鞘脂质代谢通路相关基因的表达;靶基因预测结果显示,有6条miRNA能与NlSPT1结合,13条miRNA能与NlSMase4结合;沉默NlSPT1和NlSMase4的差异miRNA的靶基因显著富集在细胞核和蛋白质结合等生物学过程以及内吞作用、内质网加工、MAPK信号通路、TOR信号通路、凋亡、脂质代谢等代谢通路。【结论】NlAgo1、NlDicer1和NlDrosha依赖性的miRNA通过影响鞘脂质代谢相关基因的表达影响鞘脂质代谢。NlSPT1和NlSMase4沉默引起褐飞虱卵巢miRNA表达水平的改变。研究结果可为基于鞘脂质代谢基因为靶标的害虫防治提供理论依据。 展开更多
关键词 褐飞虱 微小RNA 鞘脂质 RNA干扰 small RNA测序
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Blood-brain barrier pathology in cerebral small vessel disease 被引量:5
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作者 Ruxue Jia Gemma Solé-Guardia Amanda J.Kiliaan 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第6期1233-1240,共8页
Cerebral small vessel disease is a neurological disease that affects the brain microvasculature and which is commonly observed among the elderly.Although at first it was considered innocuous,small vessel disease is no... Cerebral small vessel disease is a neurological disease that affects the brain microvasculature and which is commonly observed among the elderly.Although at first it was considered innocuous,small vessel disease is nowadays regarded as one of the major vascular causes of dementia.Radiological signs of small vessel disease include small subcortical infarcts,white matter magnetic resonance imaging hyperintensities,lacunes,enlarged perivascular spaces,cerebral microbleeds,and brain atrophy;however,great heterogeneity in clinical symptoms is observed in small vessel disease patients.The pathophysiology of these lesions has been linked to multiple processes,such as hypoperfusion,defective cerebrovascular reactivity,and blood-brain barrier dysfunction.Notably,studies on small vessel disease suggest that blood-brain barrier dysfunction is among the earliest mechanisms in small vessel disease and might contribute to the development of the hallmarks of small vessel disease.Therefore,the purpose of this review is to provide a new foundation in the study of small vessel disease pathology.First,we discuss the main structural domains and functions of the blood-brain barrier.Secondly,we review the most recent evidence on blood-brain barrier dysfunction linked to small vessel disease.Finally,we conclude with a discussion on future perspectives and propose potential treatment targets and interventions. 展开更多
关键词 blood-brain barrier dysfunction cerebral blood flow cerebral hypoperfusion endothelial dysfunction HYPERTENSION inflammation magnetic resonance imaging neurovascular unit oxidative stress small vessel disease tight junctions TRANSCYTOSIS
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Cognitive impairment in cerebral small vessel disease induced by hypertension 被引量:2
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作者 Weipeng Wei Denglei Ma +1 位作者 Lin Li Lan Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1454-1462,共9页
Hypertension is a primary risk factor for the progression of cognitive impairment caused by cerebral small vessel disease,the most common cerebrovascular disease.Howeve r,the causal relationship between hypertension a... Hypertension is a primary risk factor for the progression of cognitive impairment caused by cerebral small vessel disease,the most common cerebrovascular disease.Howeve r,the causal relationship between hypertension and cerebral small vessel disease remains unclear.Hypertension has substantial negative impacts on brain health and is recognized as a risk factor for cerebrovascular disease.Chronic hypertension and lifestyle factors are associated with risks for stro ke and dementia,and cerebral small vessel disease can cause dementia and stroke.Hypertension is the main driver of cerebral small vessel disease,which changes the structure and function of cerebral vessels via various mechanisms and leads to lacunar infarction,leukoaraiosis,white matter lesions,and intracerebral hemorrhage,ultimately res ulting in cognitive decline and demonstrating that the brain is the to rget organ of hypertension.This review updates our understanding of the pathogenesis of hypertensioninduced cerebral small vessel disease and the res ulting changes in brain structure and function and declines in cognitive ability.We also discuss drugs to treat cerebral small vessel disease and cognitive impairment. 展开更多
关键词 blood-brain barrier cerebral small vessel disease cognitive impairment DEMENTIA endothelial dysfunction enlarged perivascular space HYPERTENSION lacunar infarction NEUROINFLAMMATION TREATMENT white matter high signal intensity
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Small nucleolar RNA and its potential role in the oncogenesis and development of colorectal cancer 被引量:1
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作者 Yang-Zheng Lan Zheng Wu +4 位作者 Wen-Jia Chen Ze-Xuan Fang Xin-Ning Yu Hua-Tao Wu Jing Liu 《World Journal of Gastroenterology》 SCIE CAS 2024年第2期115-127,共13页
Small nucleolar RNAs(snoRNAs)represent a class of non-coding RNAs that play pivotal roles in post-transcriptional RNA processing and modification,thereby contributing significantly to the maintenance of cellular funct... Small nucleolar RNAs(snoRNAs)represent a class of non-coding RNAs that play pivotal roles in post-transcriptional RNA processing and modification,thereby contributing significantly to the maintenance of cellular functions related to protein synthesis.SnoRNAs have been discovered to possess the ability to influence cell fate and alter disease progression,holding immense potential in controlling human diseases.It is suggested that the dysregulation of snoRNAs in cancer exhibits differential expression across various cancer types,stages,metastasis,treatment response and/or prognosis in patients.On the other hand,colorectal cancer(CRC),a prevalent malignancy of the digestive system,is characterized by high incidence and mortality rates,ranking as the third most common cancer type.Recent research indicates that snoRNA dysregulation is associated with CRC,as snoRNA expression significantly differs between normal and cancerous conditions.Consequently,assessing snoRNA expression level and function holds promise for the prognosis and diagnosis of CRC.Nevertheless,current comprehension of the potential roles of snoRNAs in CRC remains limited.This review offers a comprehensive survey of the aberrant regulation of snoRNAs in CRC,providing valuable insights into the discovery of novel biomarkers,therapeutic targets,and potential tools for the diagnosis and treatment of CRC and furnishing critical cues for advancing research into CRC and the judicious selection of therapeutic targets. 展开更多
关键词 small nucleolar RNAs Colorectal cancer DYSREGULATION BIOMARKER
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Development of small molecule drugs targeting immune checkpoints 被引量:1
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作者 Luoyi Chen Xinchen Zhao +3 位作者 Xiaowei Liu Yujie Ouyang Chuan Xu Ying Shi 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第5期382-399,共18页
Immune checkpoint inhibitors(ICIs)are used to relieve and refuel anti-tumor immunity by blocking the interaction,transcription,and translation of co-inhibitory immune checkpoints or degrading co-inhibitory immune chec... Immune checkpoint inhibitors(ICIs)are used to relieve and refuel anti-tumor immunity by blocking the interaction,transcription,and translation of co-inhibitory immune checkpoints or degrading co-inhibitory immune checkpoints.Thousands of small molecule drugs or biological materials,especially antibody-based ICIs,are actively being studied and antibodies are currently widely used.Limitations,such as anti-tumor efficacy,poor membrane permeability,and unneglected tolerance issues of antibody-based ICIs,remain evident but are thought to be overcome by small molecule drugs.Recent structural studies have broadened the scope of candidate immune checkpoint molecules,as well as innovative chemical inhibitors.By way of comparison,small molecule drug-based ICIs represent superior oral bioavailability and favorable pharmacokinetic features.Several ongoing clinical trials are exploring the synergetic effect of ICIs and other therapeutic strategies based on multiple ICI functions,including immune regulation,anti-angiogenesis,and cell cycle regulation.In this review we summarized the current progression of small molecule ICIs and the mechanism underlying immune checkpoint proteins,which will lay the foundation for further exploration. 展开更多
关键词 Immune checkpoints small molecule drugs programmed death protein 1 CD47 signal-regulatory proteinα
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Gastric metastasis of small cell lung carcinoma:Three case reports and review of literature 被引量:1
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作者 Shan Yang Qing-Yun He +5 位作者 Qing-Jing Zhao Han-Tao Yang Zheng-Yi Yang Wen-Yi Che Hua-Mei Li Hui-Chao Wu 《World Journal of Gastroenterology》 SCIE CAS 2024年第31期3717-3725,共9页
BACKGROUND Small cell lung carcinoma(SCLC)is highly susceptible to metastasis in the early stages of the disease.However,the stomach is an uncommon site of metastasis in SCLC,and only a few cases of this type of metas... BACKGROUND Small cell lung carcinoma(SCLC)is highly susceptible to metastasis in the early stages of the disease.However,the stomach is an uncommon site of metastasis in SCLC,and only a few cases of this type of metastasis have been reported.Therefore,SCLC gastric metastases have not been systematically characterized and are easily missed and misdiagnosed.CASE SUMMARY We report three cases of gastric metastasis from SCLC in this article.The first patient presented primarily with cough,hemoptysis,and epigastric fullness.The other two patients presented primarily with abdominal discomfort,epigastric distension,and pain.All patients underwent gastroscopy and imaging examinations.Meanwhile,the immunohistochemical results of the lesions in three patients were suggestive of small cell carcinoma.Finally,the three patients were diagnosed with gastric metastasis of SCLC through a comprehensive analysis.The three patients did not receive appropriate treatment and died within a short time.CONCLUSION Here,we focused on summarizing the characteristics of gastric metastasis of SCLC to enhance clinicians'understanding of this disease. 展开更多
关键词 small cell lung cancer Gastric neoplasms Neoplasm metastasis DIAGNOSIS Case report
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Enhancing Dense Small Object Detection in UAV Images Based on Hybrid Transformer 被引量:1
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作者 Changfeng Feng Chunping Wang +2 位作者 Dongdong Zhang Renke Kou Qiang Fu 《Computers, Materials & Continua》 SCIE EI 2024年第3期3993-4013,共21页
Transformer-based models have facilitated significant advances in object detection.However,their extensive computational consumption and suboptimal detection of dense small objects curtail their applicability in unman... Transformer-based models have facilitated significant advances in object detection.However,their extensive computational consumption and suboptimal detection of dense small objects curtail their applicability in unmanned aerial vehicle(UAV)imagery.Addressing these limitations,we propose a hybrid transformer-based detector,H-DETR,and enhance it for dense small objects,leading to an accurate and efficient model.Firstly,we introduce a hybrid transformer encoder,which integrates a convolutional neural network-based cross-scale fusion module with the original encoder to handle multi-scale feature sequences more efficiently.Furthermore,we propose two novel strategies to enhance detection performance without incurring additional inference computation.Query filter is designed to cope with the dense clustering inherent in drone-captured images by counteracting similar queries with a training-aware non-maximum suppression.Adversarial denoising learning is a novel enhancement method inspired by adversarial learning,which improves the detection of numerous small targets by counteracting the effects of artificial spatial and semantic noise.Extensive experiments on the VisDrone and UAVDT datasets substantiate the effectiveness of our approach,achieving a significant improvement in accuracy with a reduction in computational complexity.Our method achieves 31.9%and 21.1%AP on the VisDrone and UAVDT datasets,respectively,and has a faster inference speed,making it a competitive model in UAV image object detection. 展开更多
关键词 UAV images TRANSFORMER dense small object detection
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Small extracellular vesicles from hypoxia-preconditioned bone marrow mesenchymal stem cells attenuate spinal cord injury via miR-146a-5p-mediated regulation of macrophage polarization 被引量:1
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作者 Zeyan Liang Zhelun Yang +5 位作者 Haishu Xie Jian Rao Xiongjie Xu Yike Lin Chunhua Wang Chunmei Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2259-2269,共11页
Spinal cord injury is a disabling condition with limited treatment options.Multiple studies have provided evidence suggesting that small extracellular vesicles(SEVs)secreted by bone marrow mesenchymal stem cells(MSCs)... Spinal cord injury is a disabling condition with limited treatment options.Multiple studies have provided evidence suggesting that small extracellular vesicles(SEVs)secreted by bone marrow mesenchymal stem cells(MSCs)help mediate the beneficial effects conferred by MSC transplantation following spinal cord injury.Strikingly,hypoxia-preconditioned bone marrow mesenchymal stem cell-derived SEVs(HSEVs)exhibit increased therapeutic potency.We thus explored the role of HSEVs in macrophage immune regulation after spinal cord injury in rats and their significance in spinal cord repair.SEVs or HSEVs were isolated from bone marrow MSC supernatants by density gradient ultracentrifugation.HSEV administration to rats via tail vein injection after spinal cord injury reduced the lesion area and attenuated spinal cord inflammation.HSEVs regulate macrophage polarization towards the M2 phenotype in vivo and in vitro.Micro RNA sequencing and bioinformatics analyses of SEVs and HSEVs revealed that mi R-146a-5p is a potent mediator of macrophage polarization that targets interleukin-1 receptor-associated kinase 1.Reducing mi R-146a-5p expression in HSEVs partially attenuated macrophage polarization.Our data suggest that HSEVs attenuate spinal cord inflammation and injury in rats by transporting mi R-146a-5p,which alters macrophage polarization.This study provides new insights into the application of HSEVs as a therapeutic tool for spinal cord injury. 展开更多
关键词 bone marrow mesenchymal stem cells hypoxia preconditioning interleukin-1 receptor-associated kinase 1 MACROPHAGES mesenchymal stem cells small extracellular vesicles spinal cord injury
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H-and J-aggregation of conjugated small molecules in organic solar cells
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作者 Qiaoqiao Zhao Feng He 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期174-192,I0005,共20页
As H-and J-aggregation receive more and more attention in the research of organic solar cells(OSCs),especially in small molecular systems,deep understanding of aggregation behavior is needed to guide the design of con... As H-and J-aggregation receive more and more attention in the research of organic solar cells(OSCs),especially in small molecular systems,deep understanding of aggregation behavior is needed to guide the design of conjugated small molecular structure and the fabrication process of OSC device.For this end,this review is written.Here,the review firstly introduced the basic information about H-and J-aggregation of conjugated small molecules in OSCs.Then,the characteristics of H-and J-aggregation and the methods to identify them were summarized.Next,it reviewed the research progress of H-and J-aggregation of conjugated small molecules in OSCs,including the factors influencing H-and J-aggregation in thin film and the effects of H-and J-aggregation on OPV performance. 展开更多
关键词 H-AGGREGATION J-AGGREGATION Organic solar cells small molecules EFFICIENCY STABILITY
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Two-Layer Attention Feature Pyramid Network for Small Object Detection
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作者 Sheng Xiang Junhao Ma +2 位作者 Qunli Shang Xianbao Wang Defu Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期713-731,共19页
Effective small object detection is crucial in various applications including urban intelligent transportation and pedestrian detection.However,small objects are difficult to detect accurately because they contain les... Effective small object detection is crucial in various applications including urban intelligent transportation and pedestrian detection.However,small objects are difficult to detect accurately because they contain less information.Many current methods,particularly those based on Feature Pyramid Network(FPN),address this challenge by leveraging multi-scale feature fusion.However,existing FPN-based methods often suffer from inadequate feature fusion due to varying resolutions across different layers,leading to suboptimal small object detection.To address this problem,we propose the Two-layerAttention Feature Pyramid Network(TA-FPN),featuring two key modules:the Two-layer Attention Module(TAM)and the Small Object Detail Enhancement Module(SODEM).TAM uses the attention module to make the network more focused on the semantic information of the object and fuse it to the lower layer,so that each layer contains similar semantic information,to alleviate the problem of small object information being submerged due to semantic gaps between different layers.At the same time,SODEM is introduced to strengthen the local features of the object,suppress background noise,enhance the information details of the small object,and fuse the enhanced features to other feature layers to ensure that each layer is rich in small object information,to improve small object detection accuracy.Our extensive experiments on challenging datasets such as Microsoft Common Objects inContext(MSCOCO)and Pattern Analysis Statistical Modelling and Computational Learning,Visual Object Classes(PASCAL VOC)demonstrate the validity of the proposedmethod.Experimental results show a significant improvement in small object detection accuracy compared to state-of-theart detectors. 展开更多
关键词 small object detection two-layer attention module small object detail enhancement module feature pyramid network
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Responses of Nutrients to the Precipitation Variation and Land Use in Subtropical Monsoonal Small Mountainous Rivers:A Case Study of Baixi Watershed
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作者 TIAN Yuan GAO Fei +3 位作者 CAO Ke LV Shenghua DUAN Xiaoyong YIN Ping 《Journal of Ocean University of China》 CAS CSCD 2024年第2期383-391,共9页
Small mountainous rivers are characterized by large instantaneous fluxes and susceptible to extreme weather events,which can rapidly transport materials into the sea and have a significant impact on the ecological env... Small mountainous rivers are characterized by large instantaneous fluxes and susceptible to extreme weather events,which can rapidly transport materials into the sea and have a significant impact on the ecological environment of estuaries and bays.In order to investigate the seasonal characteristics of nutrients in small mountainous rivers in the subtropical monsoon region and the output pattern to the sea during heavy precipitation,surveys on the mountainous rivers were carried out in Baixi watershed in August 2020(wet season),March 2021(dry season)and June 2021(Meiyu period).The results showed that the dissolved inorganic nitrogen(DIN)of the rivers has an average concentration of 752μg L^(−1)in the wet season and 1472μg L^(−1)in the dry season.The concentrations of dissolved inorganic phosphorus(DIP)in wet season and dry season were 63μg L^(−1)and 51μg L^(−1),respectively.Influenced by the changes of land use in sub-watersheds,DIN concentrations in the mainstream increased from 701μg L^(−1)in the upper reaches to 1284μg L^(−1)in the middle reaches.Two rainstorms during the Meiyu period in the watershed caused the pulse runoff in the river.The maximum daily runoff reached 70 times that before rains.The maximum daily fluxes of DIN and DIP were 109 and 247 times that before rains,respectively.In view that the watershed experienced several rainstorms in the wet season,the river,with pulse runoff,carries a large amount of nutrients into the sea in a short time,which will have a significant impact on the environment of Sanmen bay and its adjacent sea. 展开更多
关键词 small mountainous river uneven precipitation RAINSTORM pulse runoff nitrogen and phosphorus
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Socio-environmental factors associated with small mammal assemblage and Leptospira prevalence in Suburban Areas of Terengganu,Malaysia
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作者 Mohammad Izuan Mohd Zamri Nur Juliani Shafie +3 位作者 Mohammad Ridhuan Mohd Ali Adedayo Michael Awoniyi Hernan Dario Argibay Federico Costa 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第9期400-407,I0002,I0003,共10页
Objective:To examine the socio-environmental factors associated with the assemblage of small mammals and the prevalence of Leptospira pathogen in poor suburban communities of Terengganu,Malaysia.Methods:We trapped sma... Objective:To examine the socio-environmental factors associated with the assemblage of small mammals and the prevalence of Leptospira pathogen in poor suburban communities of Terengganu,Malaysia.Methods:We trapped small mammals from 119 trapping points scattered around three suburban communities of Terengganu using sausage-baited live traps.On the average,we set up five traps for three nights at each sampling point during the trapping period.Kidneys of captured animals were harvested and processed for Leptospira investigation.Additionally,environmental survey was conducted at each trapping point to obtain information about possible variables supporting small mammal assemblage.We used a generalized linear model to evaluate the effect of different socio-environmental variables on small mammals’assemblage.Results:A total of 89 small mammals,specifically,Rattus norvegicus(n=39),Rattus rattus(n=27),Rattus exulans(n=10),Suncus murinus(n=11),and Tupaia glis(n=2)were captured from 1385 trap nights.Fourteen individuals(15.7%)of the captured animals tested positive for Leptospira bacteria using PCR detection.Results of our generalized linear model showed only residences bordering vacant lots as the variable positively associated with small mammal occurrence in the three study sites.Conclusions:Small mammal community,especially the often neglected species,could harbour and potentially contribute towards pathogenic Leptospira maintenance in the study sites.To adequately control small mammals’population and subsequent human zoonoses transmission,it is critical to advocate and promote appropriate infrastructure and suburban services,together with good hygiene practices that can reduce the animals’access to food and harborage. 展开更多
关键词 LEPTOSPIROSIS RODENTS small mammals control Suburban community Zoonotic diseases
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