Pancreatic hamartoma is a rare benign lesion of the pancreas characterized by a lack of typical clinical symptoms and imaging features， which leads to the difficulty in diagnosis before surgery. Since surgical intervention is often performed due to the inability to exclude the risk of malignant tumor， it may cause damage to normal pancreatic tissue. In addition， the presence of gastric mucosal tissue in pancreatic hamartoma has not been reported in the literature. This article reviews the articles on pancreatic hamartoma in China and globally and summarizes its clinical and imaging features， so as to provide help for preoperative diagnosis.

OBJECTIVETo develop a method for determination of 2, 4-dichlorophenoxyacetic acid (2, 4-D) in the air of workplace by high-performance liquid chromatography.

METHODS2, 4-D was collected by ultrafine glass filters, desorbed by methanol, separated by a C18 column, and detected by a UV detector. Identification and quantification of 2, 4-D were performed by retention time and peak areas, respectively.

RESULTSThe linear range of the test was 2∼200 µg/ml; the elution efficiency was 94.6%- 95.9%; the limit of detection (S/N = 3) was 0.034 µg/ml (injection volume of 20 µl eluant); the lower limit of quantification (S/N = 10) was 0.11 µg/ml; the minimum detectable concentration was 0.011 mg/m(3); the minimum quantifiable concentration was 0.037 mg/m(3) (with sampled air volume of 45 L).

CONCLUSIONThis method is convenient and simple in sample collection and preparation, and satisfies all methodological requirements. Therefore, this method is useful for the determination of 2, 4-D in the air of workplace.

2,4-Dichlorophenoxyacetic Acid ; analysis ; Air ; analysis ; Air Pollutants, Occupational ; analysis ; Chromatography, High Pressure Liquid ; methods ; Workplace

Objective To investigate the changes in intestinal flora in patients with extrahepatic cholangiocarcinoma (ECC) and related influencing factors. Methods Fecal samples were collected from 16 patients with ECC who were hospitalized and treated in Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital of Zhengzhou University, from January to December 2020, and absolute quantitative bacterial 16S rRNA was used for sequencing. A comparison was made with 20 patients with common bile duct stones (CBDS group) and 10 healthy controls (normal group), and the three groups were compared in terms of the differences in intestinal flora and the association with clinical indices. A one-way analysis of variance was used for comparison of normally distributed data with homogeneity of variance between the three groups, the t -test was used for comparison between two groups; the Kruskal-Wallis H test was used for comparison of non-normally distributed data between the three groups, and the Nemenyi test was used for comparison between groups. The chi-square test or the Fisher's exact test were used for comparison of categorical data between the three groups, and a Spearman correlation analysis was used to investigate correlation. Results The ECC group had significantly higher levels of total bilirubin (TBil) and direct bilirubin (DBil) than the CBDS group and the normal group. The α diversity analysis showed that there were no significant differences in observed species, Chao1 Index, and Shannon Index between the three groups (all P > 0.05), while there were significant differences in Shannon Index and Simpson Index between the three groups. The ECC group had a similar species diversity to the normal group and a significantly greater species diversity than the CBDS group ( P < 0.05), and the CBDS group had a significantly greater species diversity than the normal group ( P < 0.05). The β diversity analysis showed that the structure of intestinal flora in the ECC group was significantly different from that in the normal group and the CBDS group ( P < 0.05). The analysis of the difference in bacterial composition showed that Prevotella , Lactobacillus , Megasphaera , and Sutterella were significantly enriched in the ECC group. The correlation analysis showed that Prevotella was negatively correlated with the use of antibiotics, acid inhibitors, and liver-protecting drugs, and Lactobacillus , Megasphaera , and Sutterella were positively correlated with TBil and DBil. Conclusion There is a significant change in intestinal flora in patients with ECC, which is closely associated with liver function and the use of drugs.