Objective To establish a determination method of phthalates in the drinking water used to monitor the pollution level of phthalates in the drinking water of Beijing. Methods 23 samples from drinking water plants in Beijing were determinated by GC-MS, using selective ion mode (SIM)with high sensitivity and internal standard quantitation method with high accuracy. Results In all samples, di(2-ethylhexyl) phthalate (DEHP) was detected out and the highest concentration was 24.5 ?g/L, dibutyl phthalate (DBP) was detected out in 7 samples and the highest concentration was 11.1 ?g/L, The other 3 kinds of phthalate were not detected out. The detection limit of DEHP and DOP was 8.0 ?g/L, DMP, DEP, DBP was 0.3 ?g/L, The recovery rate were 71.7%-96.0%, RSD were 2.8%-9.0%. Conclusion The main pollutants of phthalates are DEHP and DBP in drinking water of Beijing, GC-MS is suitable for determination of phthalates in drinking water.

AIM: To explore whether the administration of rhG-CSF improve the neurological function after focal cerebral ischemia and observe the expression of fibronectin. METHODS: Injection of 10 ?g?kg -1?d -1 rhG-CSF for 5 days was given subcutaneously to rats undergoing middle cerebral artery occlusion (MCAO). Neurological severity scores (NSS) test was performed. The expression of fibronectin and Brdu were observed by immunohistochemistry. To visualize the cellular colocalization of Brdu and fibronectin, glial fibrillary acidic protein (GFAP) and fibronectin, double fluorescent staining were used. RESULTS: ① NSS at 7th day, 14th day and 21th day of groups undergoing MCAO treated with rhG-CSF were 4.00?0.89, 3.83?1.17, 3.50?1.38, respectively. NSS at 7th day, 14th day and 21th day of the control groups undergoing MCAO were 5.50?1.38, 5.83?1.47,5.66?1.63, respectively. NSS of the treated groups were significantly lower than that of the control groups (P

Alcohol is closely related to the occurrence and prognosis of cerebral ischemia.Researches on the relationship between alcohol and cerebral ischemia using different animal models draw different conclusions.This paper summarizes the common alcohol intervention methods in making animal models of cerebral ischemia, and evaluates the advantages and disadvantages of these models to provide reference for the future research.

MiRs display an important role in a variety of biological, physiological and pathological processes, including cell proliferation, differentiation, apoptosis, individual development, occurrence and progress of diseases. Recent studies have discovered that miR?424 is the significant regulatory factor of angiogenesis, and is involved in many diseases such as infectious diseases, vascular diseases, central nervous system diseases and genital system disease. This article reviews the expression, effect and possible mechanisms of miR?424 in non?tumorous diseases.

A member of miR-16 family, miR-424 has been found to be closely related with tumorigenesis, tumor progrssion, prognosis and therapy.This article reviews the expression changes, roles and possible regulating mechanisms of miR-424 in leukemia and various tumors such as breast, cervical, lung, liver and colorectal cancers.Recent studies have demonstrated that the expression of miR-424 is affected by many factors, and miR-424 could be a biomarker of diagnosis, staging and prognosis in cancers,to identify the area of tumor, and be a target of therapy.

MicroRNA-494 (miR-494) is one of the microRNAs from 14q32.31 miR-gene cluster.Recently, miR-494 was found to closely relate with tumors and other diseases .This article reviews the expression changes , roles and possible regulatory mechanisms of miR-494 in multiple tumors and other hypoxia/ischemia diseases .Recent studies demon-strate that the expression of miR-494 is affected by many factors , and miR-494 could be a biomarker of diagnosis , staging and prognosis in tumors and other diseases , and a target of therapy in future .

Objective To explore the method for simultaneous determination of arsenic and mercury in drinking water. Methods Atomic fluorescence spectrometry was applied for simultaneous determination of arsenic and mercury in drinking water. The best working conditions of the determination, such as the height of flame of atomizer, current of hollow cathode lamp, reducer, acidity and required amount of NaBH 4 were defined in this assay. Results The determination range of arsenic, the correlation coefficient and detection limit for arsenic were 0～40 ng/ml,0 999 5 and 0 10 ng/ml respectively, and were 0～80 ng/ml, 0 999 3 and 0 02 ng/ml for mercury respectively. The precisions and recovery rates of the simultaneous determination of arsenic and mercury in drinking water were 0 94%～5 61% and 94%～110%. Conclusion This method with advantages such as simple, rapid, sensitive, high accuracy and less interference, was suitable for simultaneous determination of arsenic and mercury in drinking water.

Objective To explore the long-term health effects of overexpose to radiation.Methods The 32 -41-year medical followed-up observations were performed for 25 persons exposed to ionizing radiation in the dose range of 0.10 -0.33 Gy. Observations were made of clinical symptom,eye lens,cytogenetics,immune function and endocrine function for these persons. Results The incidence of neurasthenic symptom was higher in exposed group than that in control group.2 cases suffered from liver cancer and esophageal cancer,respectively. Posterior capsule punctate phacoscotasmus of the lens wereobserved in 7 cases.There was I case of cataract in the exposed group. The frequencies of chromosomeaberration and micronucleis in peripheral blood lymphocyte in the exposed group were significantly higherthan those in control group (x2 =8.88,8.71,40.60,45.63,P ＜ 0.05 ).The average value of serum IgG was higher(t =2.16,P ＜0.05 ),while that of IgM was obviously lower in the exposed group (t =2.03,P ＜0.05).The average values of serum triiodothyronine (T3),thyroxine (T4 ) and thyroid-stimulating hormone (TSH) in the exposed group were obviously lower than those in the control group (t =2.40,3.54,2.13,P ＜0.05 ).Conclusions Overexposure has effect on lens,immune function,cytogenetics to some degree.It is important to observe the long-term health effect on overexposed persons.

Objective To explore the dosimetry of simplified intensity modulated radiotherapy (sIMRT)in the spinal component of craniospinal irradiation(CSI)compared with conventional plan(3D-CRT).Methods Five previously treated patients were adopted to generate 3D-CRT,3-and 5-field slMRT plans.The prescribed dose was 36 Gy to the planning target volume(PTV)in 20 fractions.The dose distributions of target volume and normal tissues,and homogeneity index(HI)were ananlyzed using the dose volume histogram.The total monitor units(MUs)were also analyzed to compare the delivery time indirectly.Results For 3D-CRT plans,the region of the neighbouring fields only received 70％ of the prescribed dose,and the maximum dose delivered in the normal tissues was increased to approximately 140％ of the prescribed dose.The homogeneity index(HI)of 3-and 5-field sIMRT were 0.09 ± 0.01 and 0.08 ±0.01,respectively,superior to that of 3D-CRT(0.18 ± 0.02,t=7.80,7.65,P＜0.05).The values of V10 for the heart of 3-and 5-field sIMRT were(8.4 ± 1.9)％ and(8.4 ± 2.0)％,respectively,lower than that of 3D-CRT((36.0 ± 6.0)％(t=13.3,13.0,P＜0.05).V20 for the thyroid gland were (12.4±1.5)％ and(12.4±1.6)％,respectively,lower than(69.4±5.7)％ of 3D-CRT(t=26.3,26.4,P＜0.05).V20 for the larynx were(17.2 ± 1.2)％ and(17.9 ± 1.5)％,respectively,lower than that of 3D-CRT[(89.4±7.0)％(t=25.5,26.5,P＜0.05)].V30for the NTwas(4.4±1.4)％,(4.9± 1.9)％,lower than that of 3 D-CRT[(31.9 ± 6.1)％(t=8.5,10.1,P＜0.05)].The averaged values of total MUs for 3-and 5-field sIMRT were 1100 ± 177 and 1160 ±204,respectively,higher than that of 3D-CRT(640 ± 151).Conclusions Compared with the 3D-CRT CSI technique,3-and 5-field sIMRT have better dose distribution and can improve target dose uniformity and protect the organs at risk.

Objective To analyze the differences in the clinical characteristics,endoscopy,pathology and therapy between the patients with new onset ulcerative colitis(UC) in the elderly versus youth and middle-aged patients.Methods A review analysis was carried out in the 178 hospitalized patients with UC in Third Hospital of Peking University from 1994 to 2010.The patients were divided into two groups according to the age of onset:UC onset at age of 60 years and older were enrolled in elderly group; UC onset at age less than sixty years were enrolled in youth and middle-aged group.The data of clinical manifestation,endoscopy,pathology,laboratory test,the severity of disease classification and therapy were analyzed and compared between the two groups.Results The elderly group consisted of 21 men and 6 women.The youth and middle-aged group consisted of 83 men and 68 women.The ratio of male was higher in elderly group than in youth and middle-aged group (77.8％ vs.55.0％,P＜0.05).No significant difference in the clinical type of UC was observed (P＞0.05).The ratio of abdominal pain in elderly group was lower than in youth and middle-aged group (44.4％ vs.78.8％,P＜0.05).There were no significant differences in other symptoms,laboratory test and the severity of disease between the two groups (all P＞0.05).The ratio of Grade Ⅰ and Ⅱwas much higher in the elderly than in youth-middle-aged group(70.4％ vs.39.9％,P＜0.05),but the ratio of Grade Ⅲ and Ⅳ was much lower in the elderly than in youth-middle group(29.6％ vs.60.1％,P＜0.05).No significant differences between the two groups were found in the extent of disease,pathological characteristics and therapy (all P＞0.05).Conclusions Compared with the youth and middle-aged patients with onset UC,the ratio of male patients was higher,the ratio of abdominal pain was lower,and the severity of endoscopic manifestation was less in the elderly patients with onset UC.