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151.
Pedro Luiz Serrano Uson Junior Raphael LC Araujo 《World journal of gastrointestinal oncology》2022,14(8):1446-1455
Bile duct tumors are comprised of tumors that originate from both intrahepatic and extrahepatic bile ducts and gallbladder tumors. These are aggressive tumors and chemotherapy is still the main treatment for advanced-stage disease and most of these cases have a poor overall survival. Strategies are aimed at treatments with better outcomes and less toxicity which makes immunotherapy an area of significant importance. Recent Food and Drug Administration approvals of immune checkpoint inhibitors (ICI) for agnostic tumors based on biomarkers such as microsatellite instability-high and tumor mutation burden-high are important steps in the treatment of patients with advanced bile duct tumors. Despite limited responses with isolated checkpoint inhibitors in later lines of systemic treatment in advanced disease, drug combination strategies have been demonstrating encouraging results to enhance ICI efficacy. 相似文献
152.
SK Vinod S Kumar LC Holloway J Shafiq 《Journal of Medical Imaging and Radiation Oncology》2010,54(2):152-160
The aim of this study was to assess the impact of F-18 fluorodeoxyglucose-positron emission tomography (FDG-PET) CT on radiotherapy planning parameters for patients treated curatively with radiotherapy for non-small-cell lung cancer (NSCLC). Five patients with stages I–III NSCLC underwent a diagnostic FDG-PET CT (dPET CT), planning FDG-PET CT (pPET CT) and a simulation CT (RTP CT). For each patient, three radiation oncologists delineated a gross tumour volume based on RTP CT alone, and fused with dPET CT and pPET CT. Standard expansions were used to generate PTVs, and a 3D conformal plan was created. Normal tissue doses were compared between plans. Coverage of pPET CT PTV by the plans based on RTP CT and dPET CT was assessed, and tumour control probabilities were calculated. Mean PTV was similar between RTP CT, dPET CT and pPET CT, although there were significant inter-observer differences in four patients. The plans, however, showed no significant differences in doses to lung, oesophagus, heart or spinal cord. The RTP CT plan and dPET CT plan significantly underdosed the pPET PTV in two patients with minimum doses ranging from 12 to 63% of prescribed dose. Coverage by the 95% isodose was suboptimal in these patients, but this did not translate into poorer tumour control probability. The effect of fused FDG-PET varied between observers. The addition of dPET and pPET did not significantly change the radiotherapy planning parameters. Although FDG-PET is of benefit in tumour delineation, its effect on normal tissue complication probability and tumour control probability cannot be predicted. 相似文献
153.
目的:考察甲壳胺对不同性质药物的适应性。方法:选择了盐酸麻黄碱,盐酸心得安,卡马西平,磺胺嘧啶,阿司匹林,法莫替丁,朴热息痛,潘生丁,茶碱,炎痛喜康,水杨酸等不同性质的11种药物,以甲胺为阻滞剂,制备了缓释型骨架片溶出效果。结果:甲壳胺的缓释作用随药物碱性增强,分子量增大,溶解度降低而增强,结论:甲 胺对不同性质的药物均有一定缓释作用。 相似文献
154.
Compounds exerting a mitoinhibitory effect on normal hepatocytes are potent
promoters in the resistant hepatocyte model of chemical carcinogenesis in
combination with stimulation of regenerative growth by partial hepatectomy
or treatment with carbon tetrachloride. 2- Acetylaminofluorene (2-AAF)
almost completely inhibits liver cell regeneration after partial
hepatectomy, allowing only resistant cells to participate in regenerative
growth. After initiation by diethylnitrosamine and promotion with 2-AAF and
partial hepatectomy (PH), focal growth of initiated cells generates liver
lesions which occupy 40% of the hepatic volume three weeks after PH. In
this work the mechanism for the anti promoting effects of phenobarbital and
3- methylcholantrene were investigated as well as their effects on the
development of malignant hepatocellular carcinoma in the resistant
hepatocyte model. Treatment with phenobarbital or, especially, 3-
methylcholanthrene rendered normal rat hepatocytes resistant to the
mitoinhibitory effect of 2-AAF. In combination with 2-AAF/PH, 3-
methylcholanthrene shortened the regenerative growth period to less than
one week. In the Solt-Farber protocol for experimental
hepatocarcinogenesis, treatment with phenobarbital or 3- methylcholanthrene
during promotion with 2-AAF/PH permitted hepatocytes surrounding the focal
lesions to respond with regenerative growth. The foci and surrounding liver
grew until the liver/body mass index reached the control value. With
phenobarbital treatment the total focal volume was 20% of the liver volume
three weeks after PH, whereas the corresponding value in the case of
3-methylcholanthrene was only 1%. Labelling index data supported the
conclusion that growth of the liver lesions in the resistant hepatocyte
model was dependent on differential inhibition of normal hepatocyte growth
by the promoter and that the size of the foci obtained was related to the
length of time after PH required to complete liver regeneration.
3-methylcholanthrene induced 2- AAF resistance prevented the development of
large persistent nodules and hepatocellular carcinoma while phenobarbital
delayed cancer development with several month. The data thus supports the
idea that the degree of clonal expansion during promotion determines the
size of the population at risk for malignant transformation, as well as the
final frequency of carcinomas.
相似文献
155.
氯屈膦酸二钠合成工艺改进 总被引:1,自引:0,他引:1
目的:对氯屈膦酸二钠的合成工艺进行了研究。方法:以二溴甲烷和亚膦酸三异丙酯为原料,经缩合,氯化,热裂解和成盐反应得到氯屈膦酸二钠。结果:合成产物的化学结构经元素分析,红外光谱,质谱和核磁共振谱确证,总收率为60.3%。结论:此合成路线是完全可行的。 相似文献
156.
0 引言 东方人接受皮肤磨削术治疗后色素沉着的发生率明显高于西方人.尽管采用了目前被认为是最适宜亚洲人的铒激光治疗,色素沉着仍可发生.因此,在实施该手术治疗前应严格掌握适应证,制定严密的预防治疗措施,使得色素沉着的发生率降至最低,从而最大限度的防止医疗纠纷的发生.1 对象和方法1.1 对象 21例患者,男2例,女19例,平均年龄29.2(08~48)岁.皱纹祛除8例,浅表疤痕7例,浅咖啡斑、黑子5例,不良纹眉1例.铒激光其它适应证:①老年斑;②细小皱纹;③“白皮肤”雀斑;④痤疮后疤痕⑤色素减退… 相似文献
157.
158.
159.
160.
Neural crest tumors: I-123 MIBG imaging in children 总被引:3,自引:0,他引:3
Paltiel HJ; Gelfand MJ; Elgazzar AH; Washburn LC; Harris RE; Masters PR; Golsch GJ 《Radiology》1994,190(1):117