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81.
对114例不同类型和级别的结肠癌进行银染核仁形成区嗜银蛋白(Ag-NORs)形态定量研究.结果表明,Ag-NORs数量、大小和分布在结肠未分化癌和印戒细胞癌组与管状腺癌和粘液腺癌组比较,有明显差异.管状腺癌随分化程度的降低,Ag-NORs的数量、形态、大小和分布也发生等级性变化.结果提示,Ag-NORs形态定量的数量、形态、大小和分布4项指标对结肠癌分型有一定意义,对管状腺癌分级有较好的诊断价值。 相似文献
82.
国产4环/7层PET仪初试 总被引:1,自引:0,他引:1
对我国1996年研制成功的4环/7层PET仪(轴向视野8cm)进行试用。先进行模型试验和动物实验,然后对1例正常志愿者和7例患者进行18F脱氧葡萄糖(FDG)PET显像。静脉注射18FFDG370MBq后约15小时显像,成人全身显像行11个床位采集,约15小时,心脑局部显像行2~3个床位采集,约半小时。直径1~3cm的阴模和阳模皆可显示。8例全身冠状和矢状断层影像清晰,正常志愿者(正常进食)可见脑和心肌显影,膀胱内放射性较多。2例恶性肿瘤患者的6处病变浓聚18FFDG。2例恶性肿瘤患者手术和化疗后无复发征,显像阴性。2例良性病变处未见18FFDG浓集。1例陈旧性心肌梗塞患者18FFDG心肌断层显像与99mTc甲氧基异丁基异腈心肌血流灌注显像匹配良好。正常心肌显影与否受葡萄糖负荷的影响。8例脑皮质横断影像良好,基底节和丘脑影像有时尚欠清晰。初试结果表明,该PET仪相当于至今尚在国外广泛使用的80年代中期4环/7层PET仪水平,但具有90年代PET仪全身整体冠状和矢状断层显像的功能,可用于全身肿瘤显像、心肌活性判断和功能性癫痫灶术前定位,但仪器操作性能和软件功能尚需进一步完善。 相似文献
83.
Tsuyoshi Satoh Tadashi Watanabe Masanori Tadokoro Junichi Sakamoto Hiroki Murayama Katsuki Itoh Sadayuki Sakuma Hiroshi Takagi 《Cancer science》1992,83(4):379-386
Anti-carcinoembryonic antigen monoclonal antibody (MAb) CEA102 was produced by immunization with purified CEA and the specific accumulation of radiolabeled CEA102 in colorectal cancers was investigated by autoradiography of surgical specimens using Fuji Computed Radiography (FCR). Five patients with colorectal cancer were injected intravenously with 131 I-labeled intact CEA102 or its F(ab')2 . Primary tumor and liver metastases were successfully detected by external scanning with a gamma camera in 4 cases. Autoradiographic study of the surgical specimens using FCR showed predominant localization of 131 I-labeled CEA102 in primary tumors and liver metastases in all cases. Even a small liver metastasis (0.5 cm) was clearly visualized in the autoradiogram by FCR. The pixel distribution curves of the density of the respective tissues in the autoradiograms by FCR showed the heterogeneity of the distribution of administered radiolabeled MAb in individual tumors, but the density of the tumors was higher than that of the normal tissues. In the quantitative distribution analysis of CEA102, the uptake of the primary tumor (mean 1.10%ID/kg) was ten-fold greater than that of the normal colon mucosa (mean G.10%ID/kg). These results revealed that the application of MAb has great potential in radioimmunodetection as well as in antibody-directed therapy. 相似文献
84.
目的:研究以红霉素逆转人胃癌SGC7901/ADM亚株所呈现的多药耐药性。方法:应用递增阿霉素剂量的方法,诱导建立人胃癌细胞耐药亚株。试以红霉素逆转该耐药亚株对阿霉素等抗癌药物的耐药性,以MTT法测定各药之.细胞毒作用,用LSAB法检测亲本(SGC7901)与耐药细胞亚株(SGC7901/ADM)之P-糖蛋白的表达水平。结果:体外诱导建立之人胃癌细胞耐药亚株SGC7901/ADM,对阿霉素的相对耐受度较亲本细胞SGC7901提高了9.l倍;前者同时对长春新碱、鬼臼乙叉甙呈交叉耐药性,而对丝裂霉素和顺铂则不显示交叉耐药性。红霉素浓度为273、545、1090μmol/L时.均可提高阿霉素、长春新碱、鬼臼乙叉甙对SGC7901/ADM耐药细胞亚株的细胞毒作用。免疫细胞化学研究显示,约86%的耐药亚株表达P-糖蛋白,而亲本细胞则均为阴性。结论:非毒性剂量的红霉素可以逆转人胃癌耐药细胞株的耐药性。为临床上胃癌常规化疗方案中加用红霉素提供了实验依据。 相似文献
85.
目的探讨以蒽环类药物吡柔比星(THP)为主的联合新辅助化疗对Ⅲ期原发性乳腺癌新辅助化疗的近期临床效果。方法对138例手术前确诊的Ⅲ期原发性乳腺癌采用以吡柔比星为主的CTF方案化疗1~4个周期,观察临床疗效、保乳手术率和毒副反应。结果全组总有效率为75.4%(104/138);其中完全病理缓解1例,临床完全缓解1例(0.7%),部分缓解102例(73.9%),无变化32例(23.2%),进展2例(1.4%)。实施保乳手术7例(5.1%)。施行化疗3+4周期的疗效和保乳手术率均明显高于1+2周期者(均P〈0.05)。该方案的脱发反应轻,Ⅰ度脱发28例(20.3%);心脏毒性较小,室性期外收缩发生率1.4%(2/138),无充血性心衰病例。但骨髓抑制较明显,总发生率55.8%(77/138),其中Ⅱ度骨髓抑制发生率为27.5%(38/138),Ⅲ度骨髓抑制发生率为21.0%(29/138),Ⅳ度骨髓抑制发生率为7.2%(10/138)。结论以吡柔比星为主的CTF方案用于乳腺癌新辅助化疗心脏毒性小,近期疗效较满意;但骨髓抑制发生率高,治疗期间应予支持治疗。 相似文献
86.
骨骼肌肉恶性肿瘤增强减影MRI 总被引:5,自引:2,他引:3
目的 评估增强减影在骨骼肌肉恶性肿瘤MRI中的临床应用价值。方法 5 0例骨骼肌肉恶性肿瘤病人进行MR增强扫描 ,MR对比剂采用钆喷替酸葡甲胺 (Gd DTPA ,0 1mmol/kg) ,用T1W增强后的图像与增强前的图像进行减影。通过对比度 /噪声比值 (C/Ns值 )以及肿瘤影像征象清晰程度的比较 ,对MR减影与否进行评估。结果 MR对比增强减影图像比传统的T1W增强图像显示更清晰、更直观。所有病例都经手术和病理证实。 5 0例骨骼肌肉恶性肿瘤图像MR减影的C/Ns值比传统T1W增强图像的C/Ns值高。MR减影图像的C/Ns值为 10 9 74± 5 10 ( x±s) ,传统T1W增强图像的C/Ns值为 2 3 6 1± 3 16 (t=10 1 5 1,P <0 0 5 )。减影前后肿瘤影像征象的比较结果显示 :不规则边缘 (χ2 =7 86 ,P <0 0 5 )、肿瘤分叶 (χ2 =7 16 ,P <0 0 5 )和环形强化 (χ2 =7 4 4 ,P <0 0 5 ) ,对肿瘤影像征象清晰度差异的检出具有显著性意义。结论 MR对比增强减影比传统T1WI增强更能有效地显示骨骼肌肉恶性肿瘤。对比增强减影为检出和评估骨骼肌肉恶性肿瘤方面 ,提供了一个全新的诊断工具。 相似文献
87.
Y Miyamoto M Nakatani M Ida T Ishikawa N Okazawa M Ariizumi F Tsujimoto K Mizunuma Y Fukuda S Tada 《Journal of clinical ultrasound : JCU》1989,17(5):309-318
Ultrasonography was performed in 45 cases of gastric cancer. Specimens from all 45 cases of gastric cancer were subjects to ultrasonographic study by the water immersion method for comparison with histology. In 32 of these 45 cases in vivo ultrasonographic evaluation was performed prospectively. The overall accuracy rates for the diagnosis of the depth of cancerous invasion were almost 80% in both in vitro and in vivo studies. In vivo ultrasonographic findings agreed well with those from the specimen studies. Ultrasonography was considered to be useful in the diagnosis of gastric malignancies. 相似文献
88.
Martin A. Luchtefeld M.D. Dr. Jeffrey W. Milsom M.D. Anthony Senagore M.D. James A. Surrell M.D. W. Patrick Mazier M.D. 《Diseases of the colon and rectum》1989,32(9):733-736
Anastomotic stenosis is a poorly understood and underexamined complication of gastrointestinal surgery, reportedly most frequent
in the coloproctostomy. In order to better define this problem, a questionnaire was sent to members of the American Society
of Colon and Rectal Surgeons regarding patients with gastrointestinal anastomotic stenosis. A total of 123 patients with intestinal
anastomotic stenosis were analyzed. Eighty-two anastomoses were stapled and 41 were handsewn. Nearly all stenoses occurred
in the distal bowel (70 rectal, 23 sigmoid colon). Preoperative risk factors identified were obesity (28 patients) and abscess
(12 patients). Incomplete “doughnuts” were noted in 12 patients. Postoperative anastomotic leaks (15 patients), pelvic infection
(13 patients), and postoperative radiation (7 patients) were believed to be contributing factors. Dilatation, using a variety
of techniques, was the sole treatment for 65 patients, however, intra-abdominal surgery was necessary in 34 patients. Large
intestinal anastomotic stenosis probably occurs most commonly following coloproctostomy (both with handsewn and stapled anastomoses).
Dilatation alone resulted in adequate treatment in most patients in the study. Major surgery was required to correct this
problem in a significant number of patients (28 percent) in this series. The true incidence of anastomotic stenosis in colorectal
surgery is unknown and warrants further study.
Poster presentation at the meeting of the American Society of Colon and Rectal Surgeons, Anaheim, California, June 12 to 17,
1988. 相似文献
89.
目的:通过超声热疗配合常规放疗治疗晚期恶性肿瘤的临床研究,评价超声热疗的疗效及与疗效有关的加热参数。材料和方法: 对17 例晚期恶性肿瘤的17 个病灶用常规放疗加超声热疗。放疗用直线加速器外照射,每次2 Gy、周5 次, 总剂量40~70 Gy。热疗在放疗后30 m in 内进行,每周加热1~2 次,每次加温时间 60 m in,6~8 次一疗程。全例病人每次加温时实测肿瘤内温度。结果:在可评价的13例中,CR 23.1% (3/13)、PR 46.2% (6/13)、NC 23.1% (3/13)、PD 7.7% ( 1/13) , 有效率(CR+ PR)为69.3% 。肿瘤中心部温度达到42.5℃以上的累积时间和总加热次数是决定疗效的重要参数。在17 例患者的 89 次加温中,副作用的发生率相对较低。结论:使用超声热疗配合放疗,只要实现满负荷加温,进一步提高肿瘤的局部控制率是完全可能的 相似文献
90.
Dr. Schlomo Schneebaum MD Joseph Papo MD Moshe Graif MD Mimi Baratz MD Jack Baron MS Yehuda Skornik MD 《Annals of surgical oncology》1997,4(5):371-376
Background: Despite new adjuvant therapy, 50% of patients with colon cancer will have recurrent disease. This study investigated the
use of a radiolabeled monoclonal antibody in locating occult tumor during surgery for recurrent colorectal cancer.
Methods: Twenty-two patients with recurrent colorectal cancer underwent surgery using the radioimmunoguided surgery (RIGS) system.
All patients were subjected to abdominal and chest computed tomography (CT). Before surgery, patients were injected with the
CC49 monoclonal antibody (MoAb), anti-TAG antibody labeled with125I. Ten patients with elevated carcinoembryonic antigen (CEA) levels and no CT findings had a scintigraphy scan with an anti-CEA
MoAb labeled with99Tc. Human antimouse antibody levels of these patients were within normal limits. Surgical exploration including liver ultrasound
examination was followed by survey with a gamma-detecting probe (GDP).
Results: There was MoAb tumor localization in 100% of the patients. CT found nine tumor sites, traditional surgical exploration 30,
and the GDP 51, with 44 confirmed by pathology (hematoxylin and eosin). The RIGS system found occult tumor in 10 patients
(45.4%) and resulted in major changes in surgical procedure in 11 patients. In the 10 patients who had scintigraphy scans,
10 tumor sites were identified, whereas RIGS found an additional eight sites.
Conclusion: RIGS technology offers a substantial benefit for patients undergoing surgery for recurrent colorectal cancer and a better
chance of finding recurrent tumor intraoperatively in patients who have elevated CEA levels with no other CT findings.
Presented at the Annual Cancer Symposium of The Society of Surgical Oncology, Atlanta, Georgia, March 21–24, 1996. 相似文献