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41.
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Summary The present study provides information relevant to a number of variables which may influence response to treatment of nude mouse-grown human urothelial cancer. A number of xenotransplanted tumors were exposed to selected treatments at different transplant generations, and at various dose levels and treatment schedules. It was observed that nude mouse-grown tumors were characterized by consistency, reproducibility and biological stability not affected by the transplant generation at which they were examined. Treatment related dose response curves were steep, the sharpness of the curves depending on the degree of tumor sensitivity. Best therapeutic results were obtained at the maximum tolerated dose of cytotoxic agents under study and of importance, a 20% to 40% dose reduction with the same treatment schedule resulted in little or no activity. In addition, treatment schedule, timing and sequence of treatments and to a certain degree, tumor grade were important variables which could influence tumor response. The nude mouse-human tumor system provides important preclinical guidelines on dose, schedule, sequence and timing of treatments and can assist in designing more efficient clinical trials.  相似文献   
43.
目的:探讨子宫内膜增生性病变与子宫内膜癌的超声鉴别诊断及内膜癌肌浸程度的估价.方法:采用术前B超、术后大体标本观察测量,对123例子宫内膜病变患者的声像图资料进行分析并与手术后病理结果对照.结果:①子宫内膜病变者子宫三径之和平均值均大于正常值;②58.6%的子宫内膜增生过长病变患者内膜形态以条形、梭形和正常形态回声;35%的Ⅱ期以上子宫内膜癌患者内膜回声以积液为主兼有其它图像类型;③大于50岁患者不同病理类型病变的子宫内膜平均厚度均超过其正常内膜厚度值,但无明显的规律性.小于50岁的患者内膜增厚主要以子宫内膜增生过长病变为主占48%;④通过超声测量子宫内膜厚度判断子宫内膜癌浅肌层和深肌层浸润符合率均为71.4%.结论:超声检查对判断子宫内膜病变病理类型有一定帮助,内膜厚度、内膜形态、回声特点、及内膜与肌层间的关系等,仅提示病变存在的可能性,要鉴别病变的良恶性、肌层浸润深度,须根据上述回声特点进行综合分析.  相似文献   
44.
OBJECTIVE: Many patients with haemorrhoids are investigated because of the fear of missing colorectal cancer (CRC). The aim of this study was to determine whether a primarily clinical approach regarding the need for investigation was safe and did not miss patients with CRC. PATIENTS AND METHODS: Data was collected prospectively on 589 consecutive patients with the principle diagnosis of haemorrhoids at first clinic visit. All had clinical assessment including rigid sigmoidoscopy and were treated by phenol injection or banding. They were categorized for (1) no review unless symptoms persisted -'One Stop SOS' (2) outpatient review or (3) investigation. To check for the development of CRC they were contacted by postal questionnaire or telephone interview with a minimum of one year from diagnosis and treatment. All 589 patients were cross-referenced with the Pathology database and the Hospital Information Services System. RESULTS: Four hundred and sixty-nine (80%) answered the questionnaire; 352 patients (60% of the total group) fell in the 'one stop SOS' outpatient category; 95 (16%) patients were followed up to review response to treatment for large haemorrhoids; 105 (18%) were investigated with barium enema (12%), flexible sigmoidoscopy (4%), colonoscopy (1%) and miscellaneous (1%); 37 (6%) patients were either given a haemorrhoidectomy date or referred on with a different diagnosis. No patients selected for 'one-stop' treatment developed CRC. Five (0.8%) patients were diagnosed with CRC after appropriate investigation was instituted for suspicious symptoms. One patient with distal transverse colon cancer had a delayed diagnosis as she was investigated initially by flexible sigmoidoscopy. CONCLUSION: Most patients with the primary diagnosis of symptomatic haemorrhoids do not need investigation.  相似文献   
45.
目的 为构建生物人工肝进行肝细胞的准备。方法 采用胶原酶半原位灌流法分离单个乳猪肝细胞,并对其活力及单层和聚集培养后的白蛋白、尿素合成功能进行检测。结果 采用本方法从每头乳猪中分离到的单个肝细胞数为(3.1±1.5)×10~(10),活性超过95%。在加入激素和生长因子的培养基中单层培养时,肝细胞功能良好,可维持2周左右。而在未加入激素和生长因子的培养中肝细胞虽能存活1周,但功能于24h后即丧失。球形聚集培养可实现肝细胞的大量培养,且生物学活性较单层培养显著提高。结论 采用胶原酶半原位灌注法所得单个乳猪肝细胞基本能满足构建生物人工肝对肝细胞数量的要求。聚集培养接种密度大,细胞生物学活性高,可用于构建生物人工肝。  相似文献   
46.
徐远义  黄允宁 《宁夏医学杂志》2004,26(8):459-461,F003
目的 探讨腹腔内注射OK - 4 32增强腹腔免疫功能的机制。方法 选择非炎症和非肿瘤手术患者作为实验对象 ,实验组分别于手术前 72小时、4 8小时和 2 4小时腹腔内注射 4KE的OK - 4 32。开腹后采集腹腔内巨噬细胞 ,并用人胃癌MKN1细胞作为靶细胞对巨噬细胞的癌细胞毒性进行分析。同时采集大网膜 ,对大网膜乳斑的数量和面积进行了观察分析。结果 OK - 4 32显著增加了腹腔内巨噬细胞的数量 (P <0 .0 5 )、增强了巨噬细胞的吞噬活性和酶活性 (P <0 .0 5 )、增加了NO的分泌和巨噬细胞的癌细胞毒性 (P <0 .0 5 ) ,以及大网膜乳斑的数量和面积 (P <0 .0 5 )。结论 手术前腹腔内注射OK - 4 32可以作为预防癌细胞腹腔内种植转移的有效方法。  相似文献   
47.
The increasing demands of clinical audit have resulted in the need for accurate data collection. The use of tumour maps allows standardization of the records of patients with head and neck cancer, which facilitates collation of data in multicentre studies and makes interdepartmental comparisons more meaningful. The aim of this study was to develop an improved standard set of tumour maps for recording the stage of head and neck tumours. A review of the existing tumour diagrams was performed to identify those anatomical areas that are not adequately represented or where ambiguity exists. The areas where improvements could be made were identified as: (1) the anterior commissure of the larynx; (2) axial and sagittal views of the larynx; (3) the pyriform fossa and cervical oesophagus; (4) the oropharynx and vallecula; (5) the nasal cavity and paranasal sinuses; and (6) cervical nodal involvement. A new set of tumour maps is presented in an attempt to correct some of the limitations of the existing diagrams.  相似文献   
48.
目的 总结复方金荞麦颗粒治疗肺癌的疗效。方法 对1000例各种类型的肺癌患者采用复方金荞麦颗粒5g,3次·d^-1 口服,同时辅以中药汤剂治疗,3mo为1疗程,病情稳定后逐渐减量维持。结果本组1000例患者经3mo~15a以上治疗,基本治愈181例(18.1%),显效518例(51.8%),有效204例(20.4%),无效97例(9.7%),总有效率为90.3%。结论 复方金荞麦颗粒为抗肿瘤的纯中药制剂,具有明显抑制肿瘤细胞生长、增强免疫功能、提高患者生存质量等功效,尤其是对失去手术治疗机会、不能接受化疗和放疗的肺癌患者具有较好疗效。  相似文献   
49.
Endoscopic submucosal dissection (ESD) for colorectal cancer is not widely accepted because of its technical difficulty and the risk of perforation. In addition, the risk of peritonitis cannot be completely eliminated even if a perforation is closed successfully. Reported here are two cases of early colon cancer in which the patients sustained iatrogenic perforations of the ascending colon during conventional endoscopic mucosal resection and of the sigmoid colon during ESD, respectively, requiring abdominal decompression with an 18 G Medicut needle. Both of these perforations were successfully treated by endoscopic clipping. In conclusion, conservative medical management may be possible in patients who have undergone successful closure of colonic perforations using endoscopic clipping. In order to perform immediate endoscopic closure, abdominal decompression has been useful to decrease patient discomfort and colonic lumen collapse. Now, CO2 insufflation is being used effectively for the prevention of pneumoperitoneum.  相似文献   
50.
BACKGROUND: Breast cancer is the most common cancer in women and therefore represents a major problem in public health. Data from patients' self-report questionnaires provide valuable information about the side-effects that patients may view as having a significantly detrimental impact on their quality of life (QOL) and yet are not always recognized as important by healthcare professionals. Cosmetology is a specific care for patients and there is actually no scientific evidence regarding effects on QOL for women with breast cancer. OBJECTIVE: The purpose of this study is to assess the impact of cosmetic care on QOL in breast cancer patients during chemotherapy and radiotherapy. METHODS: We developed a prospective, multicentre, randomized, controlled study including 27 patients. All the patients had to fill in a French-validated dermatologic specific quality-of-life questionnaire to compare the QOL of the two groups, the cosmetic group and the control group, at three different times of the adjuvant treatment. RESULTS: The results show a statistically significant difference between the cosmetic group and the control group in two areas of QOL: mood state and self-perception of the disease. CONCLUSION: This study emphasizes the interest of cosmetic care in breast cancer patients. However, further larger trials are needed to confirm this study.  相似文献   
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