A modification of Watkinson's method was used for the flaorimetric determination of selenium in blood, hair, urine and animal tissues with 2,3-Di-aminonaphthalene. A mixture of sulphuric, perchloric acid and sodium molybdate was used for digestion. As little as 3 ng selenium in the sample could be estimated out. Coefficients of variation and recoveries for blood, hair, urine and animal tissues were 3.9, 5.5, 3.3 and 5.6%, and 97.0, 95.0, 97.8 and 99.8% respectively. No significant difference in selenium content estimated was found as graded amounts of samples were taken for analysis, indicating no foreign interference in the extracts. Both precision and accuracy of this method are satisfactory.

2,3-Diaminonaphthalene was used for the fluorometric determination of selenium in cereals and vegetables. Nitric-perchloric-sulphuric acids mixture was used for digestion. Coefficient of variation and recovery for cereals were 4-10% and 97.1%, and for vegetables were 4-18% and 97.8% respectively. Addition of hydrochloric acid to the final digests could be omitted for ordinary cereals and soybean, but it was necessary for samples from seleni-ferous area and some vegetables with higher selenium content such as mushrooms.

Objective:The present study aimed to conduct a clinical analysis of nosocomial infections in hospitalized cancer pa-tients and propose effective precautionary measures. Methods:We retrospectively analyzed 56,430 cases of discharges from the Cancer Institute and Hospital of Tianjin Medical University between January and December 2012. Results:Among 825 cases, the rate of noso-comial infections was 1.46%;46.42%of the patients aged>60 years. The highest infection rate was observed in the Medical Depart-ment of Stomach Cancer. The highest composing rate was recorded in the Department of Hepatobiliary Cancer. The major pathogenic bacteria were Gram-negative bacilli;fungal infections were relatively rare. The most vulnerable body parts were the abdomen and diges-tive tract, which were mainly infected by pathogenic Escherichia coli. Conclusion:Healthcare workers should consider the importance of influencing factors and take precautionary measures to reduce the rate of nosocomial infections in cancer patients.

OBJECTIVETo evaluate the diagnostic value of dynamic monitoring of C-reactive protein (CRP) in drainage fluid in predicting early anastomotic leakage after colorectal surgery.

METHODSThis study enrolled 172 patients, who were diagnosed as colorectal cancer before operation and underwent radical surgery, without residual tumor tissues by postoperative pathology and perioperative infection, at the Tianjin Medical University Cancer Hospital between July 2015 and January 2016. The C-reactive(CRP) protein level in drainage fluid was continuously monitored from postoperative days (POD) 1 to 5. CRP level was compared between anastomotic leakage (AL) group and non-anastomotic leakage (NAL) group. Receiver operating characteristics (ROC) curve was used to estimate the value of monitoring CRP in drainage fluid to predict anastomotic leakage after colorectal surgery.

RESULTSAmong 172 patients, 101 cases were male and 71 cases were female, with age of (59.9±10.3) years. Anastomotic leakage occurred after colorectal surgery in 24 cases(14.0%, AL group ) and other 148 cases were defined as NAL group. Other than body mass index (BMI), differences in baseline data were not statistically significant between two groups. The CRP lever in AL group and NAL group showed rising trend from POD1 to POD4 [Day 1: (6.7±8.4) g/L vs. (8.0±10.6) g/L; Day 2: (24.8±14.6) g/L vs. (28.3±21.1) g/L, Day 3: (54.8±26.5) g/L vs. (53.8±27.6)g/L, Day 4: (62.0±32.2) g/L vs. (58.4±30.7) g/L], while the differences were not significant (all P>0.05). At POD 5, the CRP lever of AL group increased continuously, while that of NAL group decreased with significant difference [(65.3±38.9) g/L vs. (44.7±39.5) g/L, t=-2.85, P=0.005]. Further stratification analysis on AL group revealed CRP level in early AL (AL occurrence POD 10) showed rising trend from POD 1 to 4, then decreased slightly at POD 5, but whose differences were not significant (all P>0.05). ROC curve was drawn with AL condition as state variables and CRP level as test variables. The AUC of POD 1 to 4 was 0.425, 0.487, 0.510, 0.522 respectively and the AUC of POD 5 was the largest, 0.657 (95%CI:0.537-0.777). The largest Youden Index was 0.274. The critical value of CRP was 27.15 g/L. When this value was used as the point of tangency to predict the occurrence of AL, the sensitivity was 87.5%, the specificity was 39.9%, positive predictive value was 19.1%, and negative predictive value was 95.2%.

CONCLUSIONContinuous increase of CRP level in abdominal drainage fluid from POD 1 to POD 5 indicates the occurrence of AL after colorectal cancer operation, especially the detection of CRP level at POD 5 is important.