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991.
<正>牙源性纤维瘤是一类来源于牙源性间叶组织的良性肿瘤,临床上极为少见,组织病理上牙源性纤维瘤由大量的胶原纤维构成,牙源性上皮细胞构成的上皮岛和上皮条索分布其间,组织内可能含有类似于发育异常的牙本质、发育不良的牙骨质及骨样物质所构成的钙化物。中心性牙源性纤维瘤是一种发生于颌骨中心性的良性肿瘤,我科曾收治1例发生于下颌骨的中心性牙源性纤维瘤,现报告如下。  相似文献   
992.
Tca-8113细胞系单细胞体外增殖的实验观察   总被引:3,自引:1,他引:2  
目的:观察舌鳞癌Tca-8113细胞系的单细胞体外增殖能力,寻找肿瘤干细胞存在的依据,从而为鉴定其表面标记物奠定理论基础。方法:采用有限稀释法对舌鳞癌Tca-8113细胞进行单细胞体外培养,了解舌鳞癌细胞(Tca-8113)的分裂、增殖特点。结果:单细胞培养8d后,舌鳞癌Tca-8113细胞株中具有持续增殖能力的细胞占肿瘤细胞的10.85%,12d后,继续分裂增殖的细胞比例为5.23%,16d后,仅有5.09%的细胞继续增殖。结论:舌鳞癌Tca-8113细胞具有异质性,仅有少量细胞具有持续增殖能力,而这部分细胞是否就是舌鳞癌Tca-8113细胞的肿瘤干细胞。还有待进一步的实验研究证实。  相似文献   
993.
Although multifarious tumor-targeting modifications of nanoparticulate systems have been attempted in joint efforts by our predecessors, it remains challenging for nanomedicine to traverse physiological barriers involving blood vessels, tissues, and cell barriers to thereafter demonstrate excellent antitumor effects. To further overcome these inherent obstacles, we designed and prepared mycoplasma membrane (MM)-fused liposomes (LPs) with the goal of employing circulating neutrophils with the advantage of inflammatory cytokine-guided autonomous tumor localization to transport nanoparticles. We also utilized in vivo neutrophil activation induced by the liposomal form of the immune activator resiquimod (LPs-R848). Fused LPs preparations retained mycoplasma pathogen characteristics and achieved rapid recognition and endocytosis by activated neutrophils stimulated by LPs-R848. The enhanced neutrophil infiltration in homing of the inflammatory tumor microenvironment allowed more nanoparticles to be delivered into solid tumors. Facilitated by the formation of neutrophil extracellular traps (NETs), podophyllotoxin (POD)-loaded MM-fused LPs (MM-LPs-POD) were concomitantly released from neutrophils and subsequently engulfed by tumor cells during inflammation. MM-LPs-POD displayed superior suppression efficacy of tumor growth and lung metastasis in a 4T1 breast tumor model. Overall, such a strategy of pathogen-mimicking nanoparticles hijacking neutrophils in situ combined with enhanced neutrophil infiltration indeed elevates the potential of chemotherapeutics for tumor targeting therapy.  相似文献   
994.
995.
Background: Craniovertebral junction (CVJ) schwannomas are rare, with surgery and stereotactic radiosurgery (SRS) being effective yet challenging options. We systematically reviewed the literature on CVJ schwannomas. Methods: PubMed, Scopus, Web-of-Science, and Cochrane were searched following the PRISMA statement to include studies reporting CVJ schwannomas. Clinical features, management, and outcomes were analyzed. Results: We collected 353 patients from 101 included articles. Presenting symptoms were mostly neck pain (30.3%) and headache (26.3%), with most cranial neuropathies involving the XII (31.2%) and X (24.4%) nerves. Most tumors originated from C2 (30.9%) and XII (29.4%) nerves, being extracranial (45.1%) and intradural-extradural (44.2%). Erosion of C1–C2 vertebrae (37.1%), the hypoglossal canal (28.3%), and/or jugular foramen (20.1%) were noted. All tumors were operated, preferably with the retrosigmoid approach (36.5%), with the far-lateral approach (29.7%) or with the posterior approach and cervical laminectomy (26.9%), far-lateral approaches (14.2%), or suboccipital craniotomy with concurrent cervical laminectomy (14.2%). Complete tumor resection was obtained most frequently (61.5%). Adjuvant post-surgery stereotactic radiosurgery was delivered in 5.9% patients. Median follow-up was 27 months (range, 12–252). Symptom improvement was noted in 88.1% of cases, and cranial neuropathies showed improvement in 10.2%. Post-surgical complications occurred in 83 patients (23.5%), mostly dysphagia (7.4%), new cranial neuropathies (6.2%), and cerebrospinal fluid leak (5.9%). A total of 16 patients (4.5%) had tumor recurrence and 7 died (2%), with median overall survival of 2.7 months (range, 0.1–252). Conclusions: Microsurgical resection is safe and effective for CVJ schwannomas. Data on SRS efficacy and indications are still lacking, and its role deserves further evaluation.  相似文献   
996.
Despite the rising evidence in favor of immunotherapy (IT), the treatment of oncological patients affected by so-called “cold tumors” still represents an open issue. Cold tumors are characterized by an immunosuppressive (so-called cold) tumor microenvironment (TME), which favors host immune system suppression, cancer immune-escape, and a worse response to IT. However, the TME is not a static element, but dynamically mutates and can be changed. Radiotherapy (RT) can modulate a cold microenvironment, rendering it better at tumor killing by priming the quiescent host immune system, with a consequent increase in immunotherapy response. The combination of TME radiomodulation and IT could therefore be a strategy for those patients affected by cold tumors, with limited or no response to IT. Thus, this review aims to provide an easy, rapid, and practical overview of how RT could convert the cold TME and why cold tumor radiomodulation could represent an interesting strategy in combination with IT.  相似文献   
997.
Cystic teratomas are germ cell tumors most commonly found in the ovaries and testes. The pancreas, however, is very rare as a site of occurrence. Moreover, only two cases of cystic teratoma with concomitant neuroendocrine tumor have been reported to date. We report the case of a 33-year-old female who presented with abdominal pain. Computed tomography and magnetic resonance imaging of the upper abdomen revealed an 85 mm cystic tumor in the head of the pancreas. Cystic teratoma and mucinous cystadenoma were suggested as differential diagnoses. Cytopathologic analysis of endoscopic ultrasound-guided fine needle aspiration was consistent with mucinous cystadenoma. Therefore, the patient underwent surgical resection. Histologic analysis revealed a mature cystic teratoma of the pancreas with a concomitant neuroendocrine tumor. The patient is in great condition at 8 months follow-up. Cystic teratoma of the pancreas with a concomitant neuroendocrine tumor is an extremely rare condition. Surgical resection remains the mainstay of treatment as it provides a definitive diagnosis and no recurrences have been reported to date.  相似文献   
998.
Objective: Emerging studies have demonstrated the promising clinical value of circulating tumor cells(CTCs)for diagnosis, disease assessment, treatment monitoring and prognosis in epithelial ovarian cancer. However, the clinical application of CTC remains restricted due to diverse detection techniques with variable sensitivity and specificity and a lack of common standards.Methods: We enrolled 160 patients with epithelial ovarian cancer as the experimental group, and 90 patients including 50 pat...  相似文献   
999.
目的 探讨大型桥小脑角肿瘤经乳突后小骨窗开颅、骨片复位的手术方法 及其治疗效果.方法 18例大型桥小脑角肿瘤(听神经鞘瘤13例,脑膜瘤3例,胆脂瘤2例)均采用单侧乳突后小骨窗开颅,应用显微神经外科技术进行肿瘤切除,必要时磨开内听道,术中行脑干听觉诱发电位(BAEP)、体感诱发电位(SEP)和面神经功能监测,肿瘤切除后严密缝合硬脑膜,骨片复位.结果 肿瘤全切除17例、次全切除1例.全组患者的面神经均得到了解剖保留.无手术死亡.术后复查MRI示17例肿瘤全切除者未见有肿瘤残留,1例听神经鞘瘤行次全切除者于内听道内可见少许肿瘤组织残留,术后3个月行伽玛刀治疗.术后有10例遗留轻度面瘫(口角稍有歪斜,眼睑闭合良好),均为大型听神经鞘瘤患者,余患者无脑神经功能障碍,恢复良好.结论乳突后小骨窗开颅术适用于不同大小的桥小脑角肿瘤,严格按显微神经外科技术操作,结合术中BAEP,SEP和面神经功能监测,均可做到肿瘤全切除,并能有效地保护肿瘤周围的重要神经结构及其功能.严密缝合硬脑膜和骨片复位可消除局部皮下积液.  相似文献   
1000.
目的 借助癌症基因组图谱(TCGA)数据库研究低级别胶质瘤(LGG)组织中补体C3a受体1(C3AR1)的表达水平及其与LGG患者预后及肿瘤免疫细胞浸润的关系.方法 从TCGA数据库下载514例LGG患者的基因表达谱数据和临床信息.比较C3AR1基因在LGG组织和正常组织中的表达水平,分析不同WHO分级LGG组织样本中...  相似文献   
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