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211.
CONCLUSIONS: Intra-arterial infusion chemotherapy via the celiac axis combined with external beam radiotherapy might be an effective method for palliative and perioperative multimodal treatment in pancreatic cancer. To improve the dismal prognosis in resectable and nonresectable pancreatic cancer, the results of multimodal palliative, adjuvant, and neoadjuvant therapies were reviewed and put into perspective with the results of two intra-arterial palliative and adjuvant treatment studies conducted at our department. The benefits and pitfalls of each method were outweighed, resulting in a concept for performing intra-arterial chemotherapy with radiotherapy in nonresectable stage UICC-III pancreatic cancer that eventually will be developed as a combined neoadjuvant/adjuvant treatment of all potentially resectable ductal pancreatic carcinomas. 相似文献
212.
The determination of trace and ultratrace elements in biological fluids, including urine and serum, by inductively coupled plasma mass spectrometry (ICP-MS) is discussed. Nonspectral interferences and their corrections by external calibration and calibrator addition are discussed in detail. External calibration with internal calibration and dilution is mostly sufficient to correct for encountered biological matrix effects. For some elements, such as Cs and Zn, the use of calibrator addition provides more accurate results. The importance of spectral interferences and their elimination by isotope selection was also studied. Two examples, Cu and Zn, demonstrate the prime importance of selecting an isotope with minimal polyatomic interferences for analysis. By using 65Cu and 68Zn, accurate results for urine and serum can be obtained without excessive pretreatment of samples. Two reference materials, Bio-Rad Lyphochek urine and Kaulson Contox sera, were analyzed. Accuracy was evaluated by comparison with target values, and precision was estimated by the CV within 95% confidence. 相似文献
213.
A Ferlito A Rinaldo KO Devaney SL Devaney CM Milroy 《Canadian Metallurgical Quarterly》1998,112(8):710-714
An overview of the impact of the phenotype on treatment and prognosis of different laryngeal malignancies is presented. 相似文献
214.
215.
DA Litvak BM Evers KO Hwang MR Hellmich TC Ko CM Townsend 《Canadian Metallurgical Quarterly》1998,124(2):161-9; discussion 169-70
BACKGROUND: Intestinal mucosal turnover is a process of proliferation, differentiation, and apoptosis; the mechanisms remain largely undefined. The purpose of our study was to (1) assess the relationship between apoptosis and enterocyte differentiation and (2) determine whether the cell-cycle inhibitors, p21Waf1/Cip1 and p27Kip1, or the apoptosis inhibitors, Bcl-2 and Bcl-XL, may be involved. METHODS: Gut-derived Caco-2 cells were treated with sodium butyrate. Apoptosis was assessed by Hoechst stain, DNA laddering, and annexin V assay; differentiation was determined by alkaline phosphatase and sucrase activity. RNA and protein were analyzed for expression of p21Waf1/Cip1, p27Kip1, and members of the Bcl-2 family. RESULTS: Treatment of Caco-2 cells with sodium butyrate resulted in the concomitant induction of both differentiation (increased alkaline phosphatase and sucrase activity) and apoptosis. Increased levels of p21Waf1/Cip1 and p27Kip1 mRNA and protein were detected at 24 hours, occurring before apoptosis or differentiation; decreased mRNA levels of Bcl-2 and Bcl-XL were noted at 24 hours. CONCLUSIONS: Differentiation and apoptosis occurred simultaneously in Caco-2 cells, suggesting that apoptosis may be linked to enterocyte differentiation. The induction of p21Waf1/Cip1 and p27Kip1 and the down-regulation of Bcl-2 and Bcl-XL further suggest a link between the cell-cycle mechanisms regulating enterocyte differentiation and apoptosis. 相似文献
216.
Pregnant Wistar WU rats were administered PCBs (0, 5 or 25 mg Aroclor 1254 per kg body weight) by gavage on day 10 to 16 of gestation. Levels of biogenic amines were measured in the lateral olfactory tract, prefrontal cortex, striatum, hippocampus and hypothalamus in male and female offspring 21 and 90 days after birth. 5-Hydroxyindole acetic acid (5-HIAA) concentrations and the ratio of 5-HIAA/5-hydroxytryptamine (5-HT, serotonin) were significantly increased in the lateral olfactory tract, prefrontal cortex and hippocampus on postnatal day 90 in male and female offspring following maternal PCB treatment. No effects were observed on regional brain levels of dopamine, 3,4-dihydroxyphenylacetic acid, norepinephrine and homovanillic acid. The results indicate that pre- and postnatal exposure to Aroclor 1254 results in regionally specific long-term alterations in the serotonergic system. 相似文献
217.
KO Han IG Moon CS Hwang JT Choi HK Yoon HK Min IK Han 《Canadian Metallurgical Quarterly》1999,24(2):135-137
We report the case of a 7-year-old boy with a calcified leiomyoma in the right gluteal muscle. Radiography and CT showed a well-defined soft tissue mass with mulberry-like calcifications that superficially resembled chondroid matrix calcification. The mass exhibited high-signal intensity intermingled with spotty low-signal intensity on T2-weighted MRI which was attributable to extensive non-malignant degeneration of the tumour. 相似文献
218.
光缆和同轴电缆的广泛应用,使自选视像业务成为可能,高速音频神频信息(如MPEG-II)可以根据用户的需求直接从服务中心传送到用户终端。基于成本考虑,光缆或同轴电缆一般双架设至建筑物的基站,信息在建筑物内部的传递往往通过双绞线来完成。本文讨论了基于双绞线的高速信息传输系统的均衡与补偿问题,提出了一种新的前置补偿器,在提高整个系统的性能的同时,大大降低了成本。 相似文献
219.
Expression of c-erbB-2 oncogene and mutant p53 protein were detected immunohistochemically in 14 cases of myoepithelioma and 6 cases of myoepithelial carcinoma of the salivary gland. Five of the 6 myoepithelial carcinomas and nine of the 14 myoepitheliomas were overexpression of c-erbB-2 oncoprotein. The salivary ductal epithelial cells near tumors were overexpression of c-erbB-2 oncoprotein. These results indicate that c-erbB-2 may be an initial oncogene during the histogenesis of myoepithelial tumors. The p53 protein was positive in five cases of the 6 myoepithelial carcinoma, whereas all myoepitheliomas were negative. The results indicate that the mutant p53 gene may play an important role in the carcinogenesis of myoepithelial carcinoma. 相似文献
220.