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This paper uses Baker et al. (2016) to construct China's economic policy uncertainty index (EPU) and China's economic policy uncertainty index based on Chinese newspaper text keyword search (CEPU). Using monthly import data of about 5000 kinds of products in China from January 2010 to April 2016, we estimate the impact of EPU and CEPU on these products' import and find that economic policy uncertainty has different effects on imports of different products, both negative and positive. Further, we use BEC classification, differentiated products and homogeneous products, the number and concentration of countries in global trade, and the elasticity of import demand to characterize the heterogeneity of products and explain the differences in the impact of economic uncertainty on different products. We find that when the uncertainties of China's economic policy increase, capital goods and transport equipment are more negatively affected by imports than intermediate inputs and differentiated products are homogeneous products; the smaller the elasticity of demand substitution, the more countries imported globally, the lower the concentration of global importing countries, and the higher the concentration of global exporting countries, the negative reaction of product imports the bigger. In addition, we compare the performance of EPU and CEPU indices. CEPU index is more reasonable than the EPU index. [ABSTRACT FROM AUTHOR]

Antibodies play an essential role in cancer diagnosis and treatment because of the specificity for target biomolecules and reduction of side effects. However, antibodies separation and purification still face some challenges. Antibody elution from columns using a low-pH aqueous solution leads to aggregation or loss of activity of the antibody drugs. In this paper, a block copolymer-based temperature-responsive affinity chromatography (TRAC) stationary phase, SiO 2 -P[NIPAM- b -4VP]-MEP using the block temperature-responsive copolymer poly( N -isopropylacrylamide- b -4-vinylpyridine) (P[NIPAM- b -4VP]) as the space arms and 4-mercaptoethyl pyridine (MEP) as the ligand was prepared for antibody separation. The TRAC column was tested using bovine serum albumin (BSA) and γ -globulin as model proteins, and the effects of salt concentration in the mobile phase and temperature on their separation were studied in detail. At 40 ℃, the TRAC stationary phase only selectively retained γ -globulin due to the specific affinity interaction between antibodies and the ligand MEP. At 5 ℃, γ -globulin can be eluted from the column with a mass recovery of 92.7% using a Tris-HCl buffer (pH 8.0) solution containing 0.6 mol/L NaCl. The adsorption capacity of γ -globulin on this stationary phase was (71.5 ±2.1) mg/g ( n =3), which was twice that of a traditional temperature-sensitive affinity chromatography stationary phase SiO 2 -PNIPAM-MEP. The stationary phase was also used to separate and purify immunoglobulin (IgG) in human serum in one step by altering the temperature and ion strength of the mobile phase, resulting in a purity of 97.4%±0.7%. Thus, this new technology has specific selectivity for antibodies, as well as mild and green elution conditions, ultimately resolving the problem of traditional affinity chromatography using acid elution, which can lead to the antibodies aggregation/inactivation. This technology has great application potential for the industrial production of antibody drugs.

Objective: A high-performance liquid chromatography (HPLC) method was developed for the determination of theanine in puer tea without derivatization and HPLC for EGCG and caffeine with ingredient elution system was put forward., Methods: The theanine in the tea was extracted with water. The EGCG and caffeine was extracted with water: ethanol (3:7) by ultrasonic oscillation. After centrifugation, the extract was analyzed by HPLC-PDAD with a C18column and at the flow rate 1 ml/min. The theanine was determinated with 5 mmol/L SDS-acetonitrile mobile phase system (72:28), and both EGCG and caffeine with 0.05 mmol/L KH2PO4-methonal mobile phase system (80:20)., Results: The calibration of three ingredients was in good linearity. The recovery range is 85%-110%. The RSD is less than 10%., Conclusion: The method is accurate and stable.

Objective: To investigate the indications, safety and effectiveness of intracranial deployment of stents in treatment of systematic intracranial artery stenosis., Methods: Stent-assisted angioplasty was performed upon 7 consecutive patients with symptoms of intracranial artery stenosis unresponsive to anticoagulant therapy and antiplatelet therapy. The lesions involved the middle cerebral artery in 3 cases, distal end of internal carotid artery in one case, basilar artery in one case, and intracranial section of vertebral artery in 2 cases. Short-term clinical and angiographic data were obtained., Results: Symptoms of procedure-related intracranial hemorrhage and intracranial haematoma developed later were found in one patient. Emergency craniotomy was performed 5 hours after the stenosis-assisted angioplasty. The remaining patients experienced alleviation of symptoms without transient ischemic attack and apoplexy during the short-term follow-up. Angiography showed that the stenosis degree reduced from 83% to 5%. 0 - 3 months of follow-up by transcranial Doppler showed good patency of stented lesions., Conclusion: Stent-assisted angioplasty effectively treats atherosclerotic intracranial stenosis lesions. Long-term follow-up and further clinical/technical research are still needed.