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101.
102.
本实验应用流式细胞光度术研究鼻咽癌上皮样细胞株(CNE)的细胞周期动力学。结果发现CNE细胞仍保持原代细胞的DNA含量水平(超三倍体和亚四倍体),随着细胞接种时间的延长细胞周期中G0/G1时相细胞的百分数逐渐升高,而S%和G2+M%则逐渐降低。该项研究还发现随着孵育时间的延长,细胞周期中各时相细胞的运动均逐渐延缓,其中以G0/G1和G2+M时相细胞的运动减慢较为明显。 相似文献
103.
The antitumorigenic effect of cryptoporic acid E (CPA-E), a dimeric drimane sesquiterpenoid isolated from the fungus Cryptoporus volvatus , on colon carcinogenesis was investigated. Female F344 rats given an intrarectal instillation of 2 mg of N-methyl-N-nitrosourea 3 times weekly in weeks 1 and 2 were fed diet containing 0.2% CPA-E from week 3. Femal ICR mice given 15 weekly intraperitoneal injections of 10 mg of 1,2-dimethylhydrazine/kg body weight during weeks 1 to 15 were fed diet containing 0.06% CPA-E from week 1. The experiment was terminated at week 35 for rats and at week 25 for mice. The incidence and the number of tumors per animal were reduced in CPA-E-fed animals compared to the controls: 31% vs. 75% (P<0.05) and 0.4±0.2 (SEM) vs. 0.9 ± 0.2 (0.1> P >0.05) in rats, and 31% vs. 63% (0.1>P>0.05) and 0.4±0.2 vs. 2.4 ± 0.8 (P<0.05) in mice (16 animals in each group). Intrarectal deoxycholic acid-induced colonic mucosal ornithine decarboxylase activity was significantly lowered in CPA-E-fed animals compared to controls. This shows an antipromoting activity of CPA-E against colon carcinogenesis. Thus, it was concluded that CPA-E inhibits colon cancer development in both rats and mice treated with 2 different colon carcinogens. 相似文献
104.
目的 探讨胃癌腹腔微转移情况的检测方法及意义。方法 手术中切除肿瘤前收集腹腔冲洗液,采用磁激活细胞分离术(MACS)对不同病理分期胃癌患者腹腔冲洗液中癌细胞进行富集并检测。分别标记带磁珠的细胞角蛋白(CK)抗体,经磁柱富集CK^+上皮细胞,用流式细胞仪检测其含量,并比较胃癌组与胃平滑肌瘤组(对照组)以及胃癌不同分期之间、磁富集前后CK^+上皮细胞含量的差异。结果 在未经MACS富集的标本中较少发现CK^+ CD45^-细胞;在富集后的标本中其含量在胃癌组与对照组有显著差异(41/50,1/10,P〈0.001);pTNMⅠ~Ⅱ期与Ⅲ~Ⅳ期之间(0.67%,3.42%,P〈0.001)差异有非常显著性。结论 MACS能有效地富集上皮来源细胞,提高上皮源细胞的检出率,并能反映腹腔游离癌细胞数量;上皮细胞数量与胃癌的存在及临床病理分期有关,其有利于判断肿瘤转移和预后并指导治疗。 相似文献
105.
This paper reviews the literature on colorectal cancer from a sex and gender-based perspective. Colorectal cancer is a major cause of death in the developed world, with rates increasing in developing countries. Although described by some writers as an ‘equal opportunity’ disease, it presents more risk to men than women. Both biological, or sex-linked factors, and gender-linked factors play a part in the aetiology of the disease, while gender differences in the use of screening and treatment also help shape the mortality gap between women and men for this condition. Without an appreciation of the part played by sex and gender in the risk of colorectal cancer, and without a gender-sensitive approach to screening in particular, it is possible that the mortality gap between men and women for this condition will widen in the future. 相似文献
106.
目的:了解鼻咽癌放疗后患者咽部菌群的变化,为临床防治继发感染提供实验依据。方法:32例鼻咽癌放疗患者,于放疗前后分别在照射区域粘膜采集唾液标本,进行细菌的分离培养鉴定,测量可培养细菌的检出率、检出量和构成比。结果:与放疗前相比,放疗后照射区域的链球菌属、葡萄球菌属、白色念珠菌和绿脓杆菌检出增加;而放线菌属和奈瑟菌属检出减少(P<0.05)。结论:鼻咽癌放疗可影响咽部的微生态平衡,是导致鼻咽癌放疗后患者发生感染的重要原因之一。 相似文献
107.
Bisphosphonate-related osteonecrosis of the jaws (BRONJ) is mainly observed in patients with multiple myeloma and bone metastasis
from solid tumors receiving iv bisphosphonate therapy. The reported incidence of BRONJ is significantly higher with the iv
preparations zoledronic acid and pamidronate while the risk appears to be minimal for patients receiving oral bisphosphonates.
Currently available published incidence data for BRONJ are based on retrospective studies and estimates of cumulative incidence
range from 0.8 to 12%. The mandible is more commonly affected than the maxilla (2:1 ratio), and 60–70% of cases are preceded
by a dental surgical procedure. The signs and symptoms that may occur before the appearance of clinical evident osteonecrosis
include changes in the health of periodontal tissues, non-healing mucosal ulcers, loose teeth and unexplained soft-tissue
infection. Although the definitive role of bisphosphonates remains to be elucidated, the inhibition of physiologic bone remodeling
and angiogenesis by these potent drugs impairs the regenerative capacity of the bone causing the development of BRONJ. Tooth
extraction as a precipitating event is a common observation. The significant benefits that bisphosphonates offer to patients
clearly surpass the risk of potential side effects; however, any patient for whom prolonged bisphosphonate therapy is indicated,
should be provided with preventive dental care in order to minimize the risk of developing this severe condition. This article
provides an update review of current knowledge about clinical, pathological and management aspects of BRONJ. 相似文献
108.
109.
Alain Bernheim 《Molecular oncology》2010,4(4):309-322
The role of acquired chromosomal rearrangements in oncogenesis (cytogenomics) and tumor progression is now well established. These alterations are multiple and diverse and the products of these rearranged genes play an essential role in the transformation and growth of cancer cells. The validity of this assumption is demonstrated by the development of specific inhibitors or antibodies that eliminate tumoral cells by targeting some of these changes. Imatinib, an inhibitor of the tyrosine kinase ABL, the prototype of these targeting drugs, is yielding complete remissions in most CML patients. Knowledge of chromosomal abnormalities is becoming an essential contribution to the diagnosis and prognosis of cancers but also for monitoring minimal residual disease or relapse. The concept of the “cytogenetic uniqueness” of each cancer has resulted in personalized treatment. This investigation will expound upon, besides the recurrent genomic alterations, the numerous products of perverted Darwinian selection at the cellular level. 相似文献
110.
Objective To retrospectively analyze the therapeutic results of patients with initially di-agnosed metastatic nasopharyngeal carcinoma (NPC). Methods From January 1995 to December 1998, 46 NPC patients with distant metastases were treated in Fujian provincial cancer hospital. Among these pa-tients, 43 were single site metastasis and 3 were multiple sites metastases;The site of metastasis were 19 pa-tients in the liver, 11 in the bone, 7 in the lung, 1 in the brain, 6 in mediastinal nodes and 6 in axillary lymph nodes. All patients received standard radiotherapy to the primary site and cervical node region with a median dose of 72 Gy. Forty-one patients (89%) received 1-5 cycles chemotherapy (cisplatin and 5-flu-orouracil), and 23 (50%) received palliative irradiation to the metastatic site. Results The median surviv-al time was 20 months. The 1-, 2-, 3-year and 5-year overall survival rates were 66%, 47%, 30% and 19%, respectively. Irradiation to the metastatic sites and KPS were the significant prognostic factors. Pa-tients with palliative irradiation to the metastatic site had longer survival than those without (39 months vs. 13 months, X2=8.63, P=0.012). Patients with good performance status (KPS≥80) had better outcomes thanthose with poor performance status (26 months vs. 12 months, X2= 3.95, P=0.035) . Conclusions Active therapy may prolong the survival of patients with initially diagnosed metastatic NPC, especially for those who have good performance status. Under systematic chemotherapy, radiotherapy to the primary site and supportive care, the palliative irradiation to the metastatic site may also yield a good result. 相似文献