[XANES study of lead speciation in duckweed].

Qixiashan lead-zinc mine of Nanjing was one of the largest lead zinc deposits in East China Its exploitation has been over 50 years, and the environmental pollution has also been increasing. The lead concentration in the local environment was high, but lead migration and toxic mechanism has not been clear. Therefore, biogeochemistry research of the lead zinc mine was carried out. Using ICP-MS and Pb-L III edge XANES, lead concentration and speciation were analyzed respectively, and duckweed which can tolerate and enriched heavy metals was found in the pollution area. The results showed that the lead concentration of duckweed was 39.4 mg x kg(-1). XANES analysis and linear combination fit indicated that lead stearate and lead sulfide accounted for 65% and 36.9% respectively in the lead speciation of duckweed, suggesting that the main lead speciation of duckweed was sulfur-containing lead-organic acid.

[In vivo determination of Pb in human bone by using X-ray fluorescence analysis].

The data of in vivo XRF Pb in human bone were obtained within China by using the in vivo XRF set. The K series X-ray of Pb were applied to determine the in vivo Pb concentration in tibia and calcaneus among Chinese mainland residents. For general population, the weighted average of Pb in bone was 0.4-22.7 microg x (lead g bone mineral)(-1). The uncertainty was 7.0-12.5 microg x (lead g bone mineral)(-1), and the average minimun detection limit was 20.3 microg x (lead g bone mineral)(-1). For residents from pollution area, the maximum Pb in bone reached up to 73.9 microg x (lead g bone mineral)(-1).

Phase II trial of gefitinib in pretreated Chinese women with advanced non-small-cell lung cancer.

A phase II clinical trial was performed to evaluate the efficacy and safety of gefitinib on pretreated Chinese female non-small-cell lung cancer (NSCLC) patients. Chinese female patients with locally advanced or metastatic NSCLC who failed at least one platinum-based chemotherapy received gefitinib monotherapy (250 mg/day) between April 2002 and January 2010. The primary endpoint was overall response rate (ORR), and secondary endpoints were overall survival (OS) and progression-free survival (PFS). Of the 40 evaluable female patients, the ORR was 62.5%. All patients have responded with one (2.5%) complete response, 24 (60%) partial response, 12 (30%) stable disease, and 3 (7.5%) progressive disease. The OS and PFS were 20 months (95% CI: 11.9-28 months) and 13 months (95% CI: 8.0-17.9 months), respectively. Survival (OS and PFS) were longer in patients with good performance status and in patients older than 65 years (P < 0.05). The most frequently observed toxicities were rash/dry skin (80%), diarrhea (42.5%), and vomiting/anorexia (32.5%). Four patients developed grade 3 toxicities (rash and diarrhea) but did not require either dose reduction or discontinuation. Gefitinib is a highly effective and well-tolerated agent for Chinese women with pretreated advanced NSCLC.

[EDXRF analysis of soil heavy metals on lead-zinc orefield].

Due to the impact of lead-zinc mining and smelting, the soil of lead-zinc orefield and nearby areas has been widely polluted. Moreover, the concentration of lead and zinc was high, and their concentration range was wide. Furthermore, the impact of overlapping interference between low concentration As and high Pb was serious, and the lack of soil standards of lead and zinc was also a problem. According to these problems, the present work studied an effective solution to setting up the EDXRF analysis of Pb, As, Cd, Cu and Zn of soil on lead-zinc orefield. The measurable concentration of Pb was 4.4-23 600 microg x g(-1), and that of Zn was 7.0-39 400 microg x g(-1). The detection limit was 1.1 microg x g(-1) for Pb and 0.9 microg x g(-1) for Zn. The average relative-error was 7.6% for Pb and 6.2% for Zn.