In recent years,public health events caused by severe infectious diseases had a profound impact on human health,economic and social development.Drug stockpiling for infectious disease prevention and treatment is of great significance in improving the ability to respond to public health events.However,the drug stockpiling system of China for infectious disease prevention and treatment still needs to be improved.Based on the investigation and comparison of the current status of drug stockpiling for infectious disease prevention and treatment between China and the United States,this article proposes some suggestions according to China's specific circumstances for reference.

Objective To optimize the solid-phase synthesis process of phosphorodiamidate morpholino oligonucleotide(PMO)and determine the optimal reaction conditions.Methods The PMO tetramer PMO-TTTT was synthesized according to the reported reaction conditions,followed by purification through a semi-preparative high-performance liquid chromatography(HPLC)process.PMO-TTTT was structurally verified using nuclear magnetic resonance(NMR)and high-resolution mass spectrometry.With purified PMO-TTTT as a reference,a calibration curve was established,which subsequently guided the optimization of the reaction conditions for the solid-phase coupling reaction process,including the organic base,additives,duration of reaction and temperature.Under the optimized reaction condition,the anti-influenza A virus PMO sequence,PMO-flu,was synthesized and purified using a nucleic acid purification device.Results The optimal parameters for PMO solid-phase synthesis were determined.The organic base was N-ethylmorpholine,the additive was lithium iodide,the best temperature was 30 ℃,and the duration was 90 minutes.Conclusion The PMO solid-phase synthesis process has been established.LiI has been screened as a potent coupling reaction additive which could significantly boosts the efficiency of PMO solid-phase synthesis.

Based on the theory of "one qi circulation" founded by HUANG Yuanyu， the core disease mechanism of colorectal cancer is the innate spleen deficiency and stomach qi failing to bear downward， which leads to the turbidity assemble in large intestine， forming the carcinoma toxin， and ultimately transforms into colorectal cancer. The treatment should base on recovering the circulation of qi， Huangya Decoction （黄芽汤） as the basic formula， the circulation of qi ascending and descending as the base， adjusting ascending and descending together with Xiaqi Decoction （下气汤）， and differentiating the syndrome on yin-yang excess-deficiency； for spleen-kidney yang deficiency syndrome， treated with Tianhun Decoction （天魂汤） to supplement liver， kidney and assist yang； for liver-kidney yin deficiency syndrome， treated wtih Dipo Decoction （地魄汤） to supplement lung， kidney， and assist yang. They jointly prompt one qi circulation to provide the thoughts for the treatment of colorectal cancer by traditional Chinese medicine.

Objective:To evaluate the short-term effect of robotic pancreaticoduodenectomy (RPD) and laparoscopic pancreaticoduodenectomy (LPD) in the treatment of ampullary and periampullary tumor systematically.Methods:A systematic search of the PubMed, Embase and Cochrane library database using the key words "pancreaticoduodenectomy, duodenopanreatectpmy, whipple, laparoscopic, robotic, Da Vinci" . A systematic search of the Sinomed, Wangfang, VIP and CNKI databases including the key words "胰十二指肠切除" , "腹腔镜" , "机器人" , "达芬奇" . To investigate the differences of the conversion rate of laparotomy, incidence of postoperative complications, and the postoperative hospital stay between the RPD group and the LPD group. The software RevMan5.3 was used in this meta-analysis.Results:A total of 4 retrospective cohort studies and 1 001 patients were included in this meta-analysis, including 451 patients in the RPD group and 550 patients in the LPD group. The results of the meta-analysis showed that there were significant differences between RPD group and LPD group for the conversion rate laparotomy ( OR=0.35, 95% CI: 0.24-0.50, P<0.05). There were no significant differences between RPD group and LPD group for the incidence rate of overall complication( OR=1.23, 95% CI: 0.95-1.58, P>0.05), hemorrhage ( OR=0.71, 95% CI: 0.50-1.00, P>0.05), pancreatic fistula ( OR=1.09, 95% CI: 0.80-1.49, P>0.05), delayed gastric empty ( OR=0.81, 95%CI: 0.57-1.14, P>0.05) and hospital stay after surgery ( WMD=-2.87, 95% CI: -1.44-1.70, P>0.05). Conclusions:RPD is as safe as LPD, with the same complication rate. Therefor it is worthy for further application in medical institutions with relevant conditions.

Objective To evaluate laparoscopic surgery for Mirizzi syndrome.Methods A retrospective study was carried out on 14 patients undergoing laparoscopic operation for Mirizzi syndrome from Feb.2013 to Nov.2018.There were 4 patients of type Ⅰ,8 patients of type Ⅱ,2 patients of type Ⅲ according to Csendes classification.Results Laparoscopic procedures were successfully completed in all patients.All 4 cases of type Ⅰ received laparoscopic cholecystectomy.4 patients of type Ⅱ were given laparoscopic cholecystectomy combined with primary suture of common bile duct;the other 4 patients of type Ⅱ underwent laparoscopic cholecystectomy plus T tube drainage.2 patients of type Ⅲ were treated with laparoscopic partial-cholecystectomy combined with repair of the duct defect and T tube drainage.All the patients recovered uneventfully.The postoperative hospitalization time was 4 to 7 d,with an average of 5.5 d.There were no major postoperative complications.14 patients were followed up for 1-8 months,and there was no biliary stricture and no stone recurrences.Conclusion For cases of type Ⅰ,type Ⅱ and type Ⅲ,laparoscopic surgery is a safe treatment.

Objective To study the effectiveness and safety of prophylactic anticoagulation in the prevention of portal venous thrombosis (PVST) in patients after laparoscopic splenectomy.Methods A systematic search of the PubMed,Embase,Cochrane Library,Sinomed,Wangfang,Weipu and CNKI databases was performed to identify studies which compared outcomes in patients with or without prophylactic anticoagulation after laparoscopic splenectomy.The quality of the included studies was assessed using the Cochrane collaboration tool and the Newcastle-Ottawa Scale.Heterogeneity was evaluated using the x2 and I2 tests.The primary outcome was the incidence of postoperative PVST.Results Five studies were included into this review,which involved 206 and 168 patients with or without prophylactic anticoagulation,respectively.The incidence of PVST was significantly reduced with prophylactic anticoagulation with an odds ratio (OR) of 0.32 [95％ confidence interval (CI),0.13 ～0.79,P＜0.05].Conclusion Prophylactic anticoagulation resulted in a significant reduced incidence of PVST after laparoscopic splenectomy.

Objective To investigate the impact of combined postoperative transcatheter arterial chemoembolization (TACE) with antiviral therapy in hepatitis B-related hepatocellular carcinoma (HBV-HCC) patients with high risks of recurrence.Methods Fifty-three consecutive patients who underwent curative resection of HBV-HCC between January 2014 to February 2016 were enrolled.These patients were assigned to either the adjuvant antiviral therapy combined with TACE group (n =32),the treatment group or the no adjuvant treatment group (n =21,the control group).The recurrence-free survival (RFS) and overall survival (OS) were analyzed.Results There was no significant difference between the two groups in clinical characteristics (P＞0.05).The recurrence-free survival (RFS) (mean±S.D.) was (20.1 ± 1.8) months in the treatment group and (18.7±2.4) months in the control group (P=0.752).The 1-,2-and 3-year RFS rates of the treatment group and the control group were 65.6％ vs.57.1％,31.3％ vs.28.6％ and 15.6％ vs.14.3％,respectively (P＞0.05).The overall survival (OS) (mean±S.D.) was (26.8± 1.7) months in the treatment group and (21.1±2.2) months in the control group (P=0.037).The 1-,2-and 3-year RFS rates were 65.6％ vs.57.1％,31.3％ vs.28.6％ and 15.6％ vs.14.3％ in the treatment group and the control group,respectively.The 1-,2-,and 3-year OS rates were 87.5％ vs.66.7％,59.4％ vs.38.1％ and 43.8％ vs.19.0％ in the treatment group and the control group,respectively.Conclusion Antiviral therapy in combination with TACE did not decrease the RFS rate,but it improved the OS rate in HCC patients with high risks of recurrence.

Objective This study was to evaluate the long-term clinical efficiency of allogeneic corneal intrastromal lenticule inlay for correction of moderate and high hyperopia.Methods A prospective self-controlled case series study was adopted.Twenty-nine hyperopic patients (53 eyes) were performed with allogeneic corneal intrastromal lenticule inlays.The range of preoperative spherical equivalent was +3.75 to + 10 D,with the mean value of (+6.84±2.95)D.All the cases were followed up for 1 year.Uncorrected and best corrected visual acuity and refraction were compared between before and after operation.Corneal topography and optical coherence topography were used to examine corneal topography.Ocular response analyzer was used to evaluate the shifts of corneal hysteresis.This study followed the Helsinki declaration,and the research process was approved by the Ethic Committee of Beijing Tongren Hospital,and informed consent was signed by each donor and receptor.Results Compared with the before surgery,the uncorrected distance visual acuity (UDVA) and uncorrected near visual acuity (UNVA) were obviously improved and the spherical equivalent (SE) was obviously decresed in 3 months,6 months and 1 year after surgery,with significant differences between them (all at P＜0.05),but no significant differences were found between each postoperative time points (all at P＞0.05).One year after surgery,14 eyes (26.4％) gained one line of best corrected distance visual acuity (BCDVA),and 12 eyes (22.6％) gained two lines of BCDVA.Only 2 patients (5.66％) lost lines due to opaque lenticules,and no eye lost lines after changing the opaque lenticules.There was no obvious hyperopic fallback phenomenon.Compared with the before surgery,the average corneal curvature value (Avek) was obviously improved,the surface regularity index (SRI),surface asymmetry index (SAI) and central corneal thickness (CCT) were obviously increased in 3 months,6 months and 1 year after surgery,with significant differences between them (all at P＜0.05),but no significant differences were found between each postoperative time points (all at P ＞ 0.05).The cornea optical coherence tomography (OCT) examination showed that,after the operation,the corneal stromal implant was in place and clear.One year after surgery,the dividing line of corneal graft was still clearly visible.No significant changes of corneal hysteresis (CH) and corneal resistance factor (CRF) were seen among different time points before and after surgeries (F =1.443,P =0.216;F =1.744,P =0.128).Conclusions Allogeneic corneal small incision intrastromal lenticule inlays can be used to correct moderate and high hyperopic eye with good safety,effectiveness and predictability.It provides a new choice for hyperopic patients.

0bjective: To establish a three-dimensional finite element model of mandible and study the transverse displacement of proximal segment after Bilateral Sagittal Split Ramus Osteotomy (BSSRO) with different retrogression amounts during mastication. Methods: DICOM data of a skull model were processed with MIMICS and ANSYS software, reconstructing the 3D model including the teeth and temporomandibular joint in order to simulate BSSRO and evaluate the transverse displacement of proximal segment with different retrogression amounts during mastication. Results: The mean of proximal segment width change were 2.955 mm and 3.490 mm, when retrogression amounts of distal segmentwere 3 mm and 8 mm, respectively.No significant difference between the two groups were found (P=0.131). Meanwhile the displacement color scale of the 3D finite element models showed that the apparent transverse displacement distribution of the proximal segment was measured around the gonial area, decreased from the exterior to the interior. Conclusions The mandibular angle width was significantly expanded right after BSSRO. The masticatory muscle system and single cortical fixation system played an important role in expanding the width of proximal segment. However there was no correlation between the widening effect and retrogression amounts of distal segment of mandible.

Objective To investigate the safety and therapeutic effect of intra-carotid infusion with cold sa line in rats with acute focal cerebral ischemia-reperfusion injury.Methods 60 rats were randomly divided into six groups:sham operated group,normal infusion group,stroke group,local hypothermic group,local normothermic group,and systemic infusion group.Brain infarct volume and cerebral water content were analyzed 48 h after ischemia.Neurological deficits were assessed using the mNSS 24 h and 48 h after infarction.Results In the local hypothermic group,brain temperature was reduced to 33 to 34 ℃ within 5 to 10 minutes,and this significantly low temperature maintained to nearly 60 minutes after infusion continued.Physiological variables were not significantly different among each time point (P ＞ 0.05).No significant morphological abnormality was found in brain sections stained with TTC and HE.Animals receiving local cold infusion significantly decreased infarct volume and brain water content compared to stroke group (P ＜ 0.05).Both 24 h and 48 h mNSS in local hypothermic group was significantly lower than those in other groups (P ＜ 0.05).Conclusions Intra-carotid infusion with cold saline can quickly and effectively reduce brain temperature and is a relatively safe cooling method.Local hypothermia significantly reduced brain infarct volume,decreased brain water content and improved neurological functional outcomes after brain ischemia.