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71.
椎管内原发性孤立性纤维性肿瘤临床病理观察(附2例报告)   总被引:1,自引:0,他引:1  
目的探讨椎管内孤立性纤维性肿瘤的临床病理特征、诊断和鉴别诊断,以期提高对该肿瘤的诊断水平。方法复习2例椎管内原发性孤立性纤维性肿瘤的临床资料,并观察其组织学特征和免疫组化标记。结果2例患者男、女各1例,年龄分别为23岁和32岁,临床表现为局部神经压迫症状。MRI示椎管内髓外硬膜内占位。组织学特征为梭形、卵圆形细胞呈束状、波浪状或旋涡状排列,富于胶原纤维及伴有分支状薄壁血管。细胞未见异型性和核分裂像。免疫组化示瘤细胞Vimentin( ),CD34( ),CD99( ),Bcl-2( ),AACT(-),Actin(-),S-100(-),EMA(-),GFAP(-),CD68(-),CD117(-),SMA(-),NF(-)。结论椎管内原发性孤立性纤维性肿瘤是一种罕见的肿瘤,诊断主要依靠病理形态学及免疫组化,并应与椎管内的其他梭形细胞肿瘤鉴别。  相似文献   
72.
We report the first case of a human immunodeficiency virus (HIV)-related primary hepatic leiomyoma in an adult patient. The diagnosis was made at autopsy and confirmed by immunohistochemistry. Epstein Barr virus (EBV) was identified in tumour cells by in situ hybridization. Review of the literature revealed 13 cases of visceral myogenic tumours occuring in acquired immunodeficiency syndrome children, and only 2 cases in adults. One was a spinal epidural leiomyoma, the other multiple smooth muscle tumours of the colon and adrenal gland. This is the first report of EBV in smooth muscle neoplastic cells in an HIV-infected adult patient.  相似文献   
73.
The developmental relationship between granulosa and stromal cells in the fetal ovary was reviewed. The proliferation and expression of basic fibroblast growth factor (bFGF) and luteinizing hormone receptor (LHR) of both the granulosa and theca cells was examined in the adult ovary. Ovarian granulosa cell tumors were then studied under light and electron microscopy and for immunohistochemical expression of bFGF and LHR. In the follicular development of the adult ovary, bFGF expression in the granulosa cells was correlated with theca cell proliferation. In ovarian granulosa cell tumors, estrogen-producing tumors showed a stratified or microfollicular pattern being accompanied by theca cells which had ultrastructural features of steroid-production, and these tumor cells exhibited immunoreactivity for bFGF. In contrast, tumors with no apparent hormone-production showed a solid or gyriform pattern without admixture of theca cells, and were negative for bFGF. LHR was expressed in both types of tumor. Accordingly, bFGF may play an important role in association with the theca cell component in granulosa cell tumors.  相似文献   
74.
Summary An esthesioneuroblastoma in a 16-year-old male was studied ultrastructurally and immunohistochemically, using antiserum against tyrosine hydroxylase (TH), a rate-limiting enzyme in the catecholamine-synthesizing pathway. Tumor cells were fairly uniform in appearance, showing scantly cosinophilic cytoplasm and round to oval hyperchromatic nuclei, and were arranged in nests and cords of various sizes. Ultrastructurally, individual tumor cells had well-developed cell organelles including polyribosomes, microtubules, intermediate filaments, centrioles, Golgi apparatus and mitochondria. Secretory-like granules were occasionally found, predominantly in the cell processes. Immunohistochemically, many tumor cells were shown to be immunoreactive for TH. This finding strongly suggested that the present tumor was capable of producing catecholamines and that it might be derived from certain sympathetic neuronal cell nests in the superior nasal cavity.  相似文献   
75.
76.
BACKGROUND AND OBJECTIVES: Inguinal hernia repair is one of the most frequently performed pediatric surgical operations. Several pediatric laparoscopic inguinal hernia repair techniques have been introduced. But debate is unresolved regarding the feasibility of laparoscopy for treating pediatric inguinal hernias. METHODS: A retrospective cohort study enrolled 33 patients who underwent congenital inguinal hernia repair by either the new laparoscopic flip-flap technique or conventional open repair. Patients were divided into 2 groups according to the type of surgery: Group A included those who underwent the new laparoscopic technique, and Group B included those who underwent conventional open repair. RESULTS: Group A comprised 15 patients (mean age, 39 months), and group B comprised 18 (mean age, 44 months). Mean operative time was 47.5 minutes for Group A versus 27.5 minutes for Group B. Intraoperative complications for Group A included 1 case (7%) of vas deferens injury, and 3 cases (20%) in which the flaps were torn during suturing. In Group B, no intraoperative complications were encountered. In both groups, the mean postoperative hospital stay was 5.5 hours. Postoperative follow-up of 3 months revealed recurrence in 4 patients in Group A (27%), while there were no recurrences in Group B. CONCLUSION: Our preliminary experience shows unsatisfactory outcomes with laparoscopic flip-flap hernia repair in children. In spite of advancement in the application of laparoscopy in pediatric surgery, conventional open hernia repair is still the gold standard for children, in our experience. Future studies with more numbers and longterm follow-up should be conducted.  相似文献   
77.
78.
目的研究蟾酥注射液对小鼠移植性肿瘤 S180和人结肠癌 HT-29裸鼠移植性肿瘤的抑制作用.方法分别用小鼠 S180和人结肠癌 HT-29裸鼠两种荷瘤小鼠模型,观察药物对上述肿瘤的抑瘤作用,并镜下观察后者细胞凋亡情况.结果与荷瘤阴性对照组比较,蟾酥注射液各剂量组对小鼠 S180抑瘤率( IR)为 19.1%~38.2%(P<0.05),呈量效关系;而对人结肠癌 HT-29裸鼠移植性肿瘤的 IR为 9.5%~15.8%(P>0.05),也呈量效关系,但差异均未见统计学意义;环磷酰胺则能显著抑制小鼠 S180和 HT-29细胞裸鼠移植性肿瘤的生长( IR分别为70.7%和 67.1%, P<0.01),镜检可见其有显著促进肿瘤细胞凋亡作用;未发现实验药物出现明显的毒副作用.结论该实验所用的蟾酥注射液,对小鼠 S180有抑制作用,而对人结肠癌 HT-29裸鼠移植性肿瘤,则作用不明显,表明不同类型的肿瘤对其敏感性不同.  相似文献   
79.
年龄小于45岁原发性慢性闭角型青光眼的显微手术治疗   总被引:1,自引:0,他引:1  
目的探讨原发性慢性闭角型青光眼年轻患者临床治疗的经验和体会。方法对临床收治的41例52眼、年龄〈45岁、临床确诊为进展期或晚期原发性慢性闭角型青光眼的病例进行抗青光眼显微手术处理的病例进行回顾性分析。结果随访时间平均(32.50±5.08)个月;男16例,女25例;进展期28眼,晚期24眼;52眼均行抗青光眼手术-复合式小梁切除手术治疗;眼轴长平均(22.40±1.63)mm,其中〈21mm占17.31%,小眼球占13.46%;前房深度平均(1.90±0.39)mm,其中〈1.9mm占61.46%;超声生物显微镜检查高褶虹膜构型占59.62%,其中睫状突位置靠前者10眼;术前平均眼压(41.73±12.26)mmHg,末次术后平均眼压(12.03±4.57)mmHg,术前后眼压差异有统计学意义(t=3.520,P〈0.001)。术后并发症主要有浅前房,恶性青光眼。恶性青光眼手术处理方式包括玻璃体抽液、前段玻璃体切割以及超声乳化白内障吸除加人工晶状体植入术治疗。4眼因眼压控制不理想,行二次抗青光眼手术治疗。结论年轻原发性慢性闭角型青光眼患者,女性多见,多伴有眼轴短、前房浅等特点,抗青光眼复合式小梁手术治疗要注意防治术后浅前房、恶性青光眼的发生。术前详细检查、手术操作精细以及有效处理术后并发症将有助于提高手术成功率和减少并发症。  相似文献   
80.
A 4-year-old girl with post-surgical complete atrioventricular block received an epicardial dual chamber pacemaker system. During further growth intermittent exit block occurred, first misinterpreted as neurological seizures. The epicardial lead was replaced using a transvenous approach, and a pacemaker with an integrated home monitoring facility was implanted. After her discharge, a rise in the pacing threshold automatically initiated an event message. On the basis of this information, the patient was called in and imminent dislodgement of the ventricular lead was diagnosed by x-ray. The lead was repositioned and was found stable over 1-year follow-up.  相似文献   
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