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991.
PF方案化放治疗晚期鼻咽癌的远期疗效   总被引:29,自引:0,他引:29  
Gu Z  Wei Q  Huang K 《中华肿瘤杂志》1997,19(5):392-394
目的探索用PDD/5-Fu方案化放治疗晚期鼻咽癌的疗效。方法1989年12月~1990年12月间,选择76例Ⅲ、Ⅳ期鼻咽癌患者,先作3周期PDD(20mg(m2)-1d-1,iv,第1~5天)和5-Fu[700mg(m2)-1d-1,连续静脉滴注,第1~5天]诱导化疗,随后尽快作放疗,此为综合治疗组。以1989年作单纯放疗的86例晚期鼻咽癌患者作对照组。两组放疗方法、时间/剂量分割均相同。结果化疗有效率为89.3%,完全缓解率为18.4%。综合治疗组(综合组)总的5年生存率为48.7%,对照组为33.7%(P>0.05)。综合组T2N3和T2~4N3患者的5年生存率为44.1%和39.5%,均明显高于对照组的21.6%及20.4%(P<0.05)。结论PF方案化放治疗提高了T2~4N3患者的5年生存率。  相似文献   
992.
Opticatrophyresultsfromretrogradede-generationofopticnerve,causingtheopticdisctobecomepaleandappearshallowconcave.Itissimilarto"qingmang(opticatrophy)","shizhanhunmiao(blurredvirsion)"describedintraditionalChinesemedicine,manifestingmainlyasthatthediseasedeyeisnormalinappearance,butthepatientfeelsdiminutionofvirsion,blur-ringofvirsion,etc..Thesesituationsbecomeworseandworsedaybyday.Fundusexamina-tionshQWsthattheopticpapillalightensincolourorevengetspale,andbloodvesselsofretinaarenormalorbecom…  相似文献   
993.
Conclusion  We are morally obligated to select therapies which are maximally beneficial for patients. Promoting or discouraging the use of a particular treatment modality, such as BCT, should never be a consideration. To meet this goal, our society must establish guidelines as a part of comprehensive policy. The specialist system, launched under the auspices of the specialist system committee, will hopefully lead to further development of the Japanese Breast Cancer Society.  相似文献   
994.
Purpose. The intestinal epithelium is considered to be a feasible target for somatic gene therapy. To this end, Caco-2 cells derived from human colon carcinoma were transfected with a mouse interferon- (IFN-) expression vector and several stable sublines were established; this hetero-specific cytokine allows unexpected cellular effects to be avoided. Using the highest mouse IFN--producing sublines, the mode of IFN secretion was examined. Methods. The secretion polarity of mouse IFN- in its gene-transduced Caco-2 sublines was studied in a bicameral culture system in which the chambers were separated by microporous filters. Results. Mouse IFN- was secreted to the same extent from both apical and basolateral surfaces of the transduced cells regardless of cell aging. Conclusions. These results suggest that in the intestinal epithelium exogenous gene products such as IFNs can be delivered to both the luminal and blood sides in vivo. Thus, the intestinal epithelium may be suitable for systemic and local delivery of therapeutic proteins by gene transfer.  相似文献   
995.
In order to investigate TGFβ1 gene expression and its effect on murine tumor growth following direct intratumoral injection of naked plasmid DNA encoding human TGFβ1, LM3 murine lung adenocarcinoma cells were inoculated subcutaneously to T739 mice and grew to tumor nodules in 2 weeks. Multiple direct intratumoral injection of plasmid DNA, PMAMneo- TGFβ1, were given and compared with saline or vector plasmid administration groups. The growth of tumor was observed till the 8th week when the mice were killed for Northern blot analysis and histopathological study of tumoral tissue. The results showed that the growth of tumor was boosted in the TGFβ1 gene treated mice as compared with the control groups, whereas there was no significant difference in the metastatic behavior. Northern blot showed efficient expression of TGFβ1 mRNA in the treated group. The present study indicated that TGFβ1 may stimulate tumor growthin vivo through certain mechanisms. And direct intra-tumoral injection of nude plasmid DNA may be a promising gene transfer strategyin vivo. This work was supported by the National Natural Science Foundation of China (No. 39370761).  相似文献   
996.
We evaluated retrospectively the pharmacokinetics and boron uptakeof BSH (mercaptoundecahydrododecarborate) for Boron Neutron Capture Therapy(BNCT) in 123 patients undergoing craniotomy for intracranialtumors. The pharmacokinetics revealed that BSH could moveeasily from blood to the peripheral organs; itwas retained there and elimination was very slow.BSH after intra-arterial infusion (IA) was found tomove into the peripheral organs more easily thanafter intra-venous (IV) infusion.In patients with malignant glioma, the average valuesof boron concentration in tumor and the tumorto blood ratio (T/B ratio) after IA infusionwere 26.8 ± 19.5 g/g (range, 6.1–104.7 g/g)and 1.77 ± 1.30 (range, 0.47–6.65) respectively. Onthe other hand, after IV infusion the valueswere 20.9 ± 12.2 g/g (range, 7.0–39.7 g/g)and 1.30 ± 0.65 (range, 0.61–2.94) respectively. Thedifferences are not statistically significant. Boron uptake inmalignant glioma was about three times higher thanlow grade glioma. We found a good correlationbetween boron uptake and time interval from BSHinfusion, and 15–20 hours after BSH infusion theboron concentration in tumor was above 20 g/g10B in 69% of the malignant glioma patients;T/B ratio was above one in 75%, andabove two in 44% of them.We recommend intra-venous infusion of BSH clinically sinceit is safer, and results in sufficient boronconcentration in tumor, and the planned irradiation mightbe optimal around 15–20 hours after the BSHinfusion for treating malignant glioma.  相似文献   
997.
Boronophenylalanine (BPA) has been used for boron neutron capture therapy (BNCT) of brain tumors in both experimental animals and humans. The purpose of the present study was to determine if the efficacy of BNCT could be enhanced by means of intracarotid (i.c.) injection of BPA with or without blood-brain barrier disruption (BBB-D) and neutron irradiation using a rat brain tumor model. For biodistribution studies, F98 glioma cells were implanted stereotactically into the brains of Fischer rats, and12 days later BBB-D was carried out by i.c. infusion of 25% mannitol (1.373 mOsmol/ml), followed immediately by i.c. administration of 300, 500 or 800 mg of BPA/kg body weight (b.w.). At the 500 mg dose a fourfold increase in tumor boron concentration (94.5 g/g) was seen at 2.5 hours after BBB-D, compared to 20.8 g/g in i.v. injected animals. The best composite tumor to normal tissue ratios were observed at 2.5 hours after BBB-D, at which time the tumor: blood (T: Bl) ratio was10.9, and the tumor: brain (T: Br) ratio was 7.5, compared to 3.2 and 5.0 respectively for i.v. injected rats. In contrast, animals that had received i.c. BPA without BBB-D had T: Bl and T: Br ratios of 8.5 and 5.9, respectively, and the tumor boron concentration was 42.7g/g. For therapy experiments, initiated 14 days after intracerebral implantation of F98 glioma cells, 500 mg/kg b.w. of BPA were administered i.v. or i.c. with or without BBB-D, and the animals were irradiated 2.5 hourslater at the Brookhaven Medical Research Reactor with a collimated beam of thermal neutrons delivered to the head. The mean survival time for untreated control rats was 24 ± 3 days, 30 ± 2 days for irradiated controls, 37 ± 3 days for those receiving i.v. BPA, 52 ± 15 days for rats receiving i.c. BPA without BBB-D, and 95 ± 95 days for BBB-D followed by i.c. BPA and BNCT. The latter group had a 246% increase in life span (ILS) compared to untreated controls and a 124% ILS compared to that of i.v. injected animals. These survival data are the best ever obtained with the F98 glioma model and suggest that i.c. administration of BPA with or without BBB-D may be useful as a means to increase the efficacy of BNCT.  相似文献   
998.
A rapid method for detecting barbiturates in serum using EI-SIM   总被引:2,自引:0,他引:2  
A simple and rapid method for analysis of barbiturates in serum has been developed. In order to extract and clean barbiturates in serum, a separation column packed with Extrelut and Florisil was used, and the eluate was directly analyzed by means of electron impact selected ion monitoring (EI-SIM). Selected ions used were base peak ions of 10 barbituartes, and the internal standard used was allobarbital or secobarbital. The calibration curves were linear over the range 0.5–5 ng. Extraction of replicate serum samples containing 20 g/1.5 ml and 5 g/1.5 ml resulted in a recovery of 87.2–105.2% and 81.6–104.6%, respectively, with the exception of phenobarbital, which was 151.9% and 172.1%, respectively. Secobarbital was also analyzed in the serum of 13 patients who had been given secobarbital intravenously. In 3 out of 10 cases, Secobarbital levels greater than 1 g/ml were detected more than 72 h after administration. This method seems to have possibilities for clinical use.Paper presented at the 2nd International Symposium ADVANCES IN LEGAL MEDICINE, Berlin, Germany, August 30–September 1, 1993  相似文献   
999.
Quantitative 99mTc-dimercaptosuccinic acid (99mTc-DMSA) renal scintigraphy was used to asses ifosfamide-induced changes in renal function in 11 children who received chemotherapy for various malignancies. Serial measurements of absolute 99mTc-DMSA renal uptake, calculated on conjugated views, were performed during and after chemotherapy. Data of 37 studies obtained before and at different cumulative dose levels of ifosfamide were analysed in relation to clinical and biochemical parameters. A highly significant relationship between 99mTc-DMSA uptake and cumulative ifosfamide dose was found (P<0.001). The most frequently observed abnormal pattern on scintigraphic images was decreased kidney uptake together with increased accumulation in bladder. 99mTc-DMSA uptake was more consistent than 2-microglobulin values in urine and more sensitive than quantitative hyperaminoaciduria and tubular resorption of phosphate for the detection of ifosfamide-induced tubular dysfunction. 99mTc-DMSA uptake was decreased in both patients with and patients without clinical toxicity. Persistently reduced 99mTc-DMSA uptake was observed in four patients during follow-up; in one of them, who was asymptomatic after ifosfamide therapy, sudden onset of Fanconi syndrome was observed when he was retreated with carboplatin 1 year later. It is concluded that 99mTc-DMSA renal scintigraphy is a suitable method to assess progressive ifosfamide-induced tubular injury whereas scintigraphic imaging is helpful for interpreting renal uptake changes. The test is able to detect subclinical injury and may potentially predict high risk at retreatment.  相似文献   
1000.
Diminished availability of facilities for renal replacementtherapy is known to cause spuriously low acceptance and treatmentrates. In this context the evolution of renal replacement therapyin the former German Democratic Republic is a useful model tostudy and to quantify some of the relevant factors. We performed a survey in all dialysis units for adults in EastGermany (excluding East Berlin) by questionnaire, achievinga response rate of 97%. From December 1989 to December 1992the number of dialysis centres increased from 53 to 96 (+81%),reaching 6.7 centres p.m.p. Of these facilities, 45% were hospitalunits, 29% private units, and 26% dialysis units run by non-profithealth care organizations. The number of dialysis stations forregular dialysis treatment increased from 602 to 1276 (+112%),i.e. 89 stations p.m.p. In parallel, the number of chronic dialysispatients increased from 2127 to 3848 (+81%), i.e. 267 patientsp.m.p. A more detailed survey was carried out in Thüringen andpart of Sachsen, in a region covering 5 million inhabitants.The acceptance rate for chronic dialysis treatment has increasedfrom 49 to 107 patients p.m.p. (+115%). The average age of newpatients increased from 49 to 59 years, the proportion of patientsaged 65 years increased from 16 to 42% and the proportion ofdiabetics from 13 to 35%. Introduction of alternative treatmentmodalities became possible, with 2.3% of the patients receivinghaemofiltrations and 3% CAPD. The proportion of HBs-antigen-positivepatients decreased from 14.2% to 5%. At the end of 1989 in the former GDR (excluding East Berlin),773 patients and, at the end of 1992, 1153 patients were alivewith functioning renal transplants (+49%). The annual rate oftransplantations was 254 in 1989, and 283 in 1992 (+11%), i.e.18 transplantations p.m.p. (including East Berlin). At the end of 1989 2900 patients (193 p.m.p.), and at the endof 1992 5001 patients (347 p.m.p.), werealive on renal replacementtherapy (dialysis or functioning renal transplant) in East Germany,excluding East Berlin; this represents a 72% increase. The figures in East Germany are now almost equivalent to thosein West Germany regarding the number of admissions (incidence),whereas the number of patients on renal replacement therapyis still lower (prevalence).  相似文献   
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