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Flame atomic absorption spectrometry (FAAS) was applied to the determination of rubidium and cesium in chloride type oilfield water by considering the interferences of the coexistent K+, Na+, Ca2+, and Mg2+ ions, Standard curve method and standard addition method were compared in the determination of rubidium and cesium in the simulated oilfield water and the real oilfield water from the Nanyishan region in Qaidam Basin. Although rubidium and cesium have similar physical-chemical properties, they present different characters during their analyses using the FAAS technique. When the standard addition method was used for the determination of rubidium and cesium in the simulated oilfield water, the results of rubidium were very poor, whereas the results of cesium were satisfactory. When the standard curve method was used for the determination of rubidium and cesium in the simulated oilfield water, the results of both rubidium and cesium were satisfactory within the linear ranges of the standard curves. For the real oilfield water, standard addition method is also only applicable for the determination of cesium with a recovery ranging from 90% to 110%. While standard curve method is applicable for the determination of both rubidium and cesium with a recovery ranging from 90% to 110%.

Flame atomic absorption spectrometry was applied to the determination of micro amount of lithium in the oil field water of certain area. In order to determine which method is more appropriate for the determination of lithium content in the oil field water, standard curve method and standard addition method were compared. The effects of dilution, coexistent ions, and deionizers on the determination were studied. For the determination of lithium content in the same diluted oil field water samples, there exist obvious differences between the results obtained from standard addition method and standard curve method. Standard addition method gives results with a larger error, whereas standard curve method gives more accurate results. It is difficult to eliminate the interferences when the standard addition method is used. The standard curve method is found to be more suitable for the determination of micro amount of lithium in the oil field water for its accuracy, simplicity, and feasibility. When the standard curve method is used, both the determined lithium concentration and the recovery change with the dilution extent of the oil field water. In order to get an accurate result, the oil field water sample should be diluted to 1/200 or less. In this case, the recovery by standard addition method ranges from 94.3% to 96.9%. When sodium phosphate or sodium chloride is used as the deionizer, the recovery by standard addition method ranges from 94.6% to 98.6%, or from 94.2% to 96.3%. In the determination of lithium content in oil field water, there are larger experimental errors without the addition of any deionizer. When the concentration of coexistent ions is within an allowed range, the addition of sodium phosphate as a deionizer can eliminate the interferences of the coexistent ions with the determination of the lithium content. If sodium chloride is used as a deionizer, a more accurate result can be obtained when the sodium content in the samples is near the sodium content in the standard solutions. In general, under suitable experimental conditions, sodium chloride can be used as the deionizer for the determination of lithium content in the oil field water.

Background & Objective: The prognosis of esophageal cancer is not only affected by TNM stage but also by the level of serum vascular endothelial growth factor (S-VEGF). This study was to investigate the effect of concurrent chemoradiotherapy on S-VEGF in esophageal squamous cell carcinoma (ESCC), and to explore the correlation of S-VEGF to the prognosis of ESCC., Methods: Serum samples were obtained from ESCC patients, treated with concurrent chemoradiotherapy in Cancer Center of Sun Yat-sen University from Dec. 2002 to May 2004, before treatment and 1 month after treatment. The serum samples from sex- and age-matched healthy donors were used as controls. Two courses of chemotherapy, comprised of cisplatin and 5-fluorouracil, were given during radiotherapy at 4-week intervals. S-VEGF level was measured by ELISA. The changes of S-VEGF level before and after treatment were observed, and its correlation to progress-freely survival rate of ESCC patients was analyzed., Results: S-VEGF level was significantly higher in ESCC patients before and 1 month after treatment than in healthy controls [(516.27+/-67.89) ng/L and (347.19+/-35.42) ng/L vs. (294.20+/-23.40) ng/L, P<0.01, P=0.002]; concurrent chemoradiotherapy significantly reduced S-VEGF level (P<0.01). S-VEGF level before treatment was significantly lower in the patients achieved complete remission than in those achieved partial remission or had progressive disease [(345.82+/-76.29) ng/L vs. (669.37+/-99.04) ng/L, P =0.020]. The 1-year progress-freely survival rate was 0 in the patients with S-VEGF level of > 516.27 ng/L before treatment and >347.19 ng/L after treatment, 17% in the patients with S-VEGF level of > 516.27 ng/L and <347.19 ng/L, respectively, 57% in the patients with S-VEGF level of < 516.27 ng/L and >347.19 ng/L, respectively, and 72% in the patients with S-VEGF level of < 516.27 ng/L and <347.19 ng/L, respectively (P= 0.005)., Conclusions: S-VEGF level is higher in ESCC patients than in healthy control. Concurrent chemoradiotherapy could reduce S-VEGF level in ESCC. The changes of S-VEGF level before and after treatment may provide prognostic information for ESCC patients.

Objective: To investigate the mechanism of erectile dysfunction (ED) in rat models with chronic renal failure (CRF)., Methods: Chronic renal failure was induced by adult male Sprague-Dawley rats, which were subjected to an excisional 5/6 nephrectomy. The rats in NCRF group and CRF group were divided into three groups randomly. Injected with apomorphine(APO, 80 microg/kg), penile erections of three groups were observed and noted by the 2nd week, 4th week respectively and 6th week from the 14th day of 5/6 nephrectomy and experimental models of ED with CRF were selected; NOS activity was examined and the microstructures of penile were observed under optical microscope with computer configuration image analysis system in selected rat models., Results: Compared with the controls, the areas of smooth muscle and NOS activity in the penile cavernous tissue of ED rats with CRF decreased significantly (P < 0.01 or P < 0.05) , and collagen fibers slightly increased, and these alterations had close correlations with the duration of CRF. The, Conclusions: Penile erection is seriously affected in rats with CRF. The decreases of areas of blood sinus had no obvious changes. the number of smooth muscles and NOS activity might be the most important factors.

Objective: To analyze treatment and prognostic factors of 74 patients with dermatofibro-sarcoma protuberans (DFSP)., Methods: From August 1990 to November 1999, 74 patients with DFSP confirmed pathologically were treated. There were 52 males and 22 females with a median age of 37 years (range 4 to 80 years) on diagnosis. Seventeen patients were treated by extensive excision and 2 by limited excision. Fifty-two patients had surgical resection alone (S), and 22 postoperative radiotherapy (S + R) of 50-70 Gy. The multivariate parameters were analyzed using Cox model. Kaplan-Meier and Log-Rank test were used to evaluate the results of the recurrence-free survival., Results: The rate of recurrence was 28.4% for all patients. The 5-year recurrence-free survival rate (RFSR) was 66.6% and the 10-year RFSR was 52.5%. The 5-year and 10-year in the S group were 58.4% and 41.2%, compared with 90.0% and 83.3% in the S + R group (P < 0.05). The 5-year and 10-year RFSR in the pathologically positive margin group were 57.5% and 41.4% respectively, compared with the 75.0% and 56.6% in the pathologically negative group (P < 0.05). Multivariate analysis suggested radiotherapy and negative pathological margins were favorable prognostic factors., Conclusion: Post-operation radiotherapy and pathological margin are the independent prognostic factors.

Background & Objective: Transcatheter arterial chemoembolization (TACE) is the routine treatment for unresectable primary liver cancer, but 3-year survival rate of patients received TACE alone is only about 20%. This research was to evaluate efficacy of external radiotherapy (RT) combined with TACE on unresectable primary live cancer., Methods: From Jun. 1994 to Apr. 2002, 114 patients with unresectable primary liver cancer were non-randomized to receive TACE plus RT (54 patients), or TACE alone (60 patients) as control. For TACE, after skiagram confirmed catheterization, suspension of 300 mg of carboplatin, 50-60 mg of epirubicin, 14-20 mg of mitomycin, and 10-30 ml of iodized oil was perfused into hepatic arteries, 1-2 mm of Gelfoam particles was given to embolize hepatic arteries according to blood supply conditions of tumors, this process was repeated every 4-8 weeks. Either group was treated with 1-4 sessions of TACE. In TACE+RT group, patients received radiation on tumor and generous margin 21-28 days after TACE. The radiation dose was 46-60 Gy in daily 2 Gy fractions., Results: In TACE+RT group, response rate (AFP titer decrease of >50%) was 61.1%, and 1-, 2-, 3-year survival rates of TACE+RT group were significantly higher than those of TACE group (66.5% vs. 53.9%, 48.4% vs. 37.2%, and 37.4% vs. 17.8%, P<0.05). Three-year survival rate correlated with tumor size, liver function grade, and portal vein embolus., Conclusion: TACE combined with RT may prolong survival time of patients with unresectable primary live cancer.

With the development of multidisciplinary treatment for cancer, great changes have taken place in the therapeutic strategy of breast cancer. However, radiotherapy as a method of local management, still plays an important role in the combined treatment of breast cancer. The recurrence in the chest wall ranks the first, accounting for 44-69% of the total local-regional relapse, therefore, the chest wall is commonly regarded as the most important target of radiotherapy after mastectomy. The traditional irradiation techniques cannot reach an ideal dose distribution due to the irregular shape of the chest wall. Electron arc therapy, by using the electron characteristics of dose distribution, combining the shape of thorax and the depth of target volume, make the dose distribution of target volume more reasonable, decreases the dose of heart or lung and has more clinical benefit than traditional techniques. On the other hand, it had been demonstrated by some clinical research that irradiation with electron arc could provide a high rate of local control and generally acceptable acute and long-term toxicity, comparing with the traditional irradiation techniques.