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61.
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
62.
Ikuo Konishi 《Medical Electron Microscopy》1994,27(3-4):271-274
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
63.
64.
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
65.
Summary A case is described of symmetrical cavitating brain stem necrosis produced by cardiac arrest in a premature infant. Two months after birth this 25-week gestational age infant suffered a prolonged episode of bradycardia. She was resuscitated and then died 3 weeks later. The autopsy revealed striking bilateral cavitation of the brain stem tegmentum extending in a columnar fashion from the upper portion of the spinal cord to the hypothalamus. The findings in this case are identical to the brain stem injury experimentally produced by complete cardiac arrest in the rhesus monkey. 相似文献
66.
67.
目的 对重组人脑钠素(rhBNP)用于心脏手术围术期处理的可行性、安全性和有效性进行初步观察,并与硝普钠的作用进行比较。方法 选择择期心脏手术病人22例,随机分为rhBNP组(B组)和硝普钠(SNP)组(s组),每组11例。比较rhBNP与SNP对病人血流动力学和肝肾功能的影响。结果 与给药前和S组比较,B组用药后15、30、60、120和180min各点心输出量增加显著(P〈0.05,P〈0.01);B组与给药前比较,给药后即刻、15、30和60min时点外周血管阻力下降显著(P〈0.05);给药后即刻、15和30点与S组比较,下降显著(P〈0.05)。B组肺毛细血管楔压(PCWP)与用药前比较,用药后即刻、15、30、60、120和180min下降显著(P〈0.05,P〈0.01);与S组比较,给药后30、60、120和180min差异有统计学意义(P〈0.05,P〈0.01)。S组PCWP与用药前比较,用药后60min、120min和180min下降显著(P〈0.05)。B组与输注rhBNP前以及S组比较,平均动脉压、心率和中心静脉压差异均无统计学意义。输注rhBNP后病人24h尿量明显增加。用药过程中以及30d后进行电话随访,未见药物不良反应。结论 rhBNP用于心脏手术围术期处理是可行的,具有改善心功能和稳定循环的作用。 相似文献
68.
69.
Objective To analyze the risk factors of the postoperative mid- and long-term aortic valvular regurgitation after ROSS procedure(pulmanary valve homograft transplantation). Methods Between March 1998 and July 2007,47 patients[25male, 22 female, mean age (13.31±5.79) years, ronge 1-34 years] with aortic valvular disease underwent the Ross procedure at our insti tution. There were 6 patients suffering fron rheumatic heart disease and 41 patients suffering from congenital heart disease. The aver age aortic blood flow velocity was (4.67±3.47) m/s, the average pressure gradient across aortic valve (88.26±58.06)mm Hg, LVEDD (45.53 ±10.78) mm, EF 0.69±0.08. All the patients were followed up in out-patient departement by ultrasonic cardio gram. Multiple logistic regression analysis was performed to find out the risk factors of the postive aortic valvular regurgitation. Results There was no poetoperative death in hospital. The mean follow-up periods was (36.15±22.1) months, rasnge from 12 to 110 months and none long-dated death. Compared with the data recorded in hospital, the diamenters of the aortic sinus and aortic annu lus enlarged significantly, respectively from (26.16±5.10) mm to (32.37±6.84) tam and from (19.41 ~3.98) mm to (23.45± 5.86) mm. The average flow velocity d the homograft (new aortic valve) was(1.39±0.48) m/s, graclient pressure (8.17+6.16) mm Hg. Mild aortic regurgitstion was present in 5 patients (10.6%), moderate aortic tegmgitafion in 2 pmieats (4.3%) and aevere aortic regurgitation in 1 petient (2.1%). The rate of free from regurgitation was 82.9%. Multiple logistic analyses identified the per esence of bicuspid aortic valve, enlargement of aortic annulus and age above 14 years as the risk factors for posterative aortic regurg itation. Conclusion The Ross procedure is a safe and effective procedure with good clinical results in mid-and long-term follow-up. However, the presence of bicuspid aortic valve, enlargement of aortic annulus and age above 14 years preoperatively were identified as the risk factors for postoperative aortic regurgitation. 相似文献
70.
蟾酥注射液对小鼠S180和人结肠癌HT-29裸鼠移植性肿瘤的影响 总被引:6,自引:0,他引:6
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