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991.
目的 观察雷公藤内酯醇 (TL)是否通过降低脑组织内肿瘤坏死因子 (TNF α)含量而减少白细胞浸润 ,从而改善局灶性脑缺血再灌注所致的神经功能缺失。方法 大鼠ipTL 0 .2或 0 .4mg·kg- 1·d- 1,连续 4d。d 4给药前行右侧大脑中动脉缺血 1h再灌注 2 4h。行为观察行大鼠神经功能缺损评分 ;放射免疫法检测缺血再灌注侧大脑皮层TNF α含量。病理切片观察缺血再灌注侧脑微血管内附壁中性粒细胞计数。结果 与损伤模型组比较 ,TL处理组大脑皮质TNF α含量明显减少 ,神经功能受损程度明显改善。脑微血管内附壁中性粒细胞计数明显减少。结论 TL有抑制缺血再灌注脑组织内TNF α生成 ,降低其含量的作用 ,从而抑制白细胞浸润 ,改善受损的神经功能  相似文献   
992.
目的 研究 As2 O3引起肿瘤细胞凋亡和对细胞周期的影响。方法 采用 DNA凝胶电泳 ,流式细胞仪分析、RT- PCR和 Western免疫印迹等技术检测细胞凋亡的发生。结果 由 As2 O3诱导的人肺腺癌 GL C- 82、胃腺癌 MGC- 80 3和 SGC- 790 1、食管癌 Ec10 9、宫颈癌 He L a细胞凋亡前 ,细胞阻滞在 G2 M期 ,上述细胞均表现为对c- myc基因的下行调节 ;但在导致永生化人宫颈上皮 HCE16 /3细胞凋亡之前 ,细胞却被阻滞在 G1期 ,对 c- m yc基因表达无影响。结论  As2 O3引起细胞凋亡与细胞周期阻滞有关 ,在肿瘤细胞和前恶变的 HCE16 /3细胞中阻滞的时期不同 ,这可能与 c- myc基因表达的改变与否有关  相似文献   
993.
Congenital sacrococcygeal teratoma SCT is the most common germ cell tumor of infancy and childhood with a female preponderance. Most SCTs are diagnosed at birth, are benign, and consist of fully differentiated, mature tissues. Tumorigenesis of SCTs remains poorly understood. Almost nothing is known about possible oncogene activation or tumor suppressor inactivation in these rare tumors. We describe the presence of various oncoproteins and tumor suppressor proteins in eight cases of congenital SCT. The following oncogenes were examined: ras family c-H-, c-N-, and c-K-ras , early genes fos, jun , and tumor suppressor genes p53 and nm23-H-1 . There was no relationship between the intensity of expression of these oncoproteins and tumor suppressor genes and the following parameters: tumor size, age, and survival of the patients. We did not observe any difference, however, between the expression of the examined oncogenes and tumor suppressor genes nm23 and p53 in immature and mature teratomas. Our findings suggest that the ras family of oncogenes, fos and jun oncogenes, and nm23 and p53 tumor suppressor genes are present in congenital SCT, indicating a possible role in genesis and development of these tumors.  相似文献   
994.
995.
A 49-year-old white female patient was referred to the ENT Department, Zentralkrankenhaus, Bremen, because of conductive hearing loss. Widespread tumor formation was found in the left temporal bone and was identified by biopsy to be an osteoclastoma. The tumor was extirpated surgically and reconstruction was performed. Periodic clinical follow-ups during a 36-month period after surgery have included control computed tomographic scans and have shown no evidence for recurrent disease. The specific pathology of the osteoclastoma is presented and different ways for treatment are discussed.  相似文献   
996.
Adult granulosa-cell tumor of the ovary: a retrospective study of 45 cases   总被引:1,自引:0,他引:1  
This study describes 45 cases of adult granulosa-cell tumors seen in our institution between 1976 and 1993. The median age was 46.5 years (12–77) and 18 women were postmenopausal. Vaginal bleeding was present in one-third of cases; other complaints were abdominal pain (28%) and the presence of a pelvic mass (47%). The tumor size was variable (<3 cm to 30 cm, median 11.5 cm). FIGO stages were: stage I: 30 (73%) (19 Ia, seven Ic, four I unknown); stage II: seven (17%) (two IIa, five IIC); stage III: three (7%) (one IIIb, two IIIc). Two adenocarcinomas and 13 cases of hyperplasia were found in 25 endometrial samples available. The initial therapy for all the cases was surgery, consisting in 34 patients of hysterectomy, bilateral salpingo-oophorectomy, ± tumor resection. Sixteen patients received adjuvant therapy as well: chemotherapy (CT) alone for 12, radiotherapy (RT) alone for two, and CT + RT for two patients. Among the 39 patients who achieved a complete response after initial therapy, 15 patients have relapsed (pelvic recurrences) (38.5%) including six stage Ia (three received only conservative surgery). All the recurrent tumors were resected and 14/15 had CT (13/14 with cisplatin). The overall survival rate was 77.2% at 5 years, 66.5% at 10 years, and 41.2% at 20 years. A statistically significant difference was found between the survival of patients with stage Ia disease (75% at 10 and 15 years) and that of other patients (60% at 10 years, and <50% at 15 years). Serum estradiol and serum inhibin were measured in some patients and the results are described.  相似文献   
997.
Serum CA125 concentrations measured before and during chemotherapy may provide additional information for prognostic assessment of patients with epithelial ovarian cancer (EOC), and enable discrimination between patients who are likely to benefit from further therapy and those who will not. Medical records of 40 patients with advanced EOC, treated at the Department of Obstetrics and Gynecology of the University Hospital Nijmegen between July 1984 and April 1993, were examined. All patients had primary cytoreductive surgery followed by platinum-based chemotherapy. Serum samples were obtained before surgery and during chemotherapy. Follow-up information and patient and tumor characteristics were abstracted from medical records until December 1, 1994. By using multivariate Cox proportional hazards models for disease-free and overall survival it was evaluated whether outcome prediction was improved by inclusion of serum CA125 quantitations.
  Only FIGO stage and extent of residual tumor were significant independent prognostic factors before the start of chemotherapy. When such regression models were constructed after subsequent courses of chemotherapy, serum CA125 measurements conducted after each of the first three chemotherapy courses improved the prediction of disease-free survival. Prediction of overall survival was improved by inclusion of serum CA125 measurements after courses 1–6. Inclusion of serum CA125 measurements during chemotherapy improved prognostic assessment of patients with advanced EOC.  相似文献   
998.
Eight cases of glomus tumors hospitalized in our department from 1982 through 1995 were reviewed. It comprised of five glomus tympanic tumors and three glomus jugular tumors. Discussion was centered on it’s contemporary diagnosis, classification and surgical treatment with introduction of a modified combined intra-and extracranial surgical approach to resect the extensive glomus tumors.  相似文献   
999.
本文对骨巨细胞瘤(GCT)的传统组织学分级与其生物学行为不甚相符的原因进行了研究。采用51例GCT为研究对象,以13例骨囊肿(良性)和15例骨肉瘤(恶性)为对照组,采用图像分析仪(IAT)对细胞核(GCT取基质细胞核),进行了形态计量研究(8项参量),DNA含量,DNA倍体类型研究,及术后复发病例的DNA倍性与其传统分级的比较研究。结果经统计学处理发现GCTⅠ级和Ⅱ级之间无显著差别,且它们的生物学属性在潜在恶性和低度恶性范畴。研究还揭示GCT的DNA≥5c细胞数超过7%者系术后复发、转移的高危病例。  相似文献   
1000.
Background This retrospective study analyzed the outcome in patients with intracranial germ-cell tumors to determine whether tumor response during radiation therapy can predict achievement of primary local control with radiation therapy alone. Methods Between 1983 and 1993, 22 patients with untreated primary intracranial germ cell tumors received a total whole brain radiation dose of between 18 Gy and 45 Gy (mean 31.3 Gy) with or without a localized field of 10 to 36.4 Gy (mean, 22.4 Gy), or local irradiation only (1 patient). In 10 patients with pineal tumor only, who were treated first with radiation therapy, tumor response to radiation therapy was evaluated using computed tomography (CT) (at baseline, and approximately 20 Gy and 50 Gy). Areas of calcification in the tumor were subtracted from total tumor volume. Follow-up time ranged from 2 to 12 years. Results Five-year actuarial survival rates for patients with germinoma were 71%, 100% for patients with a teratoma component, and 100% for patients without histologic verification. Patients with germinomas or tumors suspected of being germinomas who were given more than 50 Gy had no local relapse. There was no correlation between primary local control by radiation therapy alone and initial tumor volume. The rate of tumor volume response to irradiation assesed by CT was significantly different in those patients who relapsed compared to those who did not relapse Conclusion Tumor response during radiation therapy using CT was considered to be predictive of primary local control with radiation therapy alone.  相似文献   
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