ObjectiveTo investigate the whole genomic characteristics and phylogenetic relationships of clinical isolates of enteroaggregative Escherichia coli (EAEC) in diarrhea outpatients in Pudong New Area, Shanghai. MethodsBased on the diarrheal disease surveillance network in Pudong New Area, Shanghai, whole-genome sequencing was performed on a total of 55 EAEC strains isolated from fecal samples of the diarrhea outpatients from January 2015 to December 2019. The genome analyses based on raw sequencing data encompassed genome size, coding genes, dispersed repeat sequences, genomic islands, and protein coding regions, and pan-genome analyses were conducted simultaneously. Contigs sequences assays were performed to analyze molecular characteristics including serotypes, antibiotic resistance genes, and virulence factors. The phylogenetic clusters and multilocus sequence typing (MLST) were identified, and a phylogenetic tree was constructed. ResultsEAEC exhibited an open pan-genome. The predominant serotype of EAEC in diarrhea outpatients in Pudong New Area was O130:H27, and the carriage rate of β-lactam resistance genes was the highest (67.27%, 37/55). A total of 29 virulence factors and 106 virulence genes were identified, phylogenic group B1 was the predominant group, and clonal group CC31 was the dominant clonal group. The strain distribution was highly heterogeneous. ConclusionThe genomic characteristics of EAEC displayed significant strain polymorphism. It is necessary to develop effective strategies for differential diagnosis and improve detection capabilities for infection with EAEC of different serotypes and genotypes.

ObjectiveThis paper aims to verify the therapeutic effect of Cranial Painkiller pills' extract powder prepared by the new process on the rat's trigeminal neuralgia model caused by infraorbital injection of Talci Pulvis， evaluate its potential clinical application value， and compare the therapeutic effect with that of Cranial Painkiller granules， so as to provide data support for the application of the Cranial Painkiller pills' extract powder and precise treatment. MethodsThe rat's trigeminal neuralgia model was constructed by infraorbital injection of Talci Pulvis， and the rats were randomly divided into the normal group， model group， carbamazepine group （60 mg·kg^-1）， Cranial Painkiller granules group （2.70 g·kg^-1）， and low， medium， and high dosage groups of Cranial Painkiller pills' extract powder （1.35， 2.70， 5.40 g·kg^-1） according to the basal mechanical pain thresholds， and there were 10 rats in each group. The drug was administered by gavage to each group 2 h after modeling， and distilled water was given by gavage to the normal and model groups under the same conditions once a day for 10 d. Von Frey brushes were used to measure mechanical pain thresholds in rats. Hematoxylin-eosin （HE） staining was used to detect pathological changes in the trigeminal ganglion， and enzyme-linked immunosorbent assay （ELISA） was used to detect the inflammatory factors interleukin-1 （IL-1）， interleukin-6 （IL-6）， interleukin-8 （IL-8）， and tumor necrosis factor-α （TNF-α） levels in rat serum， as well as neuropeptide substance P （SP） and β-endorphin （β-EP） levels in rat brain tissue. Western blot technique was used to detect the levels of NLRP3， ASC， Caspase-1， and OTULIN proteins in rat brain tissue. ResultsCompared with the normal group， the pain threshold of rats in the model group showed a continuous significant decrease （P<0.01）. The pathological damage of brain tissue was significant （P<0.01）， and the inflammatory levels of IL-1， IL-6， IL-8， and TNF-α in serum were significantly elevated （P<0.01）. The level of the SP in the brain tissue was significantly elevated （P<0.01）， and the level of β-EP was significantly reduced （P<0.01）， while the level of OTULIN was significantly reduced， and NLRP3， ASC， and Caspase-1 protein levels were significantly elevated （P<0.01）. After administration of the drug， compared with the model group， the pain threshold of each dose group of the Cranial Painkiller pills' extract powder and the Cranial Painkiller granules group significantly increased （P<0.01）. The inflammatory levels of IL-1， IL-6， IL-8， and TNF-α and SP levels significantly decreased （P<0.01）， and the β-EP levels were significantly elevated （P<0.01）， while the levels of OTULIN protein were significantly elevated （P<0.05， P<0.01）， and the levels of NLRP3， ASC proteins were decreased （P<0.01）in high dose Cranial Painkiller pills' extract powder. Meanwhile， compared with those in the model group， the trigeminal ganglion lesions of rats in the Cranial Painkiller pills' extract powder and Cranial Painkiller granules groups showed different degrees of improvement （P<0.05， P<0.01）. ConclusionThe Cranial Painkiller pills' extract powder has significant therapeutic effects on the rat model of trigeminal neuralgia induced by infraorbital injection of Talci Pulvis， and its mechanism is related to the improvement of OTULIN-regulated neuroinflammation.

ObjectiveThis paper aims to verify the therapeutic effect of Cranial Painkiller pills' extract powder prepared by the new process on the rat's trigeminal neuralgia model caused by infraorbital injection of Talci Pulvis， evaluate its potential clinical application value， and compare the therapeutic effect with that of Cranial Painkiller granules， so as to provide data support for the application of the Cranial Painkiller pills' extract powder and precise treatment. MethodsThe rat's trigeminal neuralgia model was constructed by infraorbital injection of Talci Pulvis， and the rats were randomly divided into the normal group， model group， carbamazepine group （60 mg·kg^-1）， Cranial Painkiller granules group （2.70 g·kg^-1）， and low， medium， and high dosage groups of Cranial Painkiller pills' extract powder （1.35， 2.70， 5.40 g·kg^-1） according to the basal mechanical pain thresholds， and there were 10 rats in each group. The drug was administered by gavage to each group 2 h after modeling， and distilled water was given by gavage to the normal and model groups under the same conditions once a day for 10 d. Von Frey brushes were used to measure mechanical pain thresholds in rats. Hematoxylin-eosin （HE） staining was used to detect pathological changes in the trigeminal ganglion， and enzyme-linked immunosorbent assay （ELISA） was used to detect the inflammatory factors interleukin-1 （IL-1）， interleukin-6 （IL-6）， interleukin-8 （IL-8）， and tumor necrosis factor-α （TNF-α） levels in rat serum， as well as neuropeptide substance P （SP） and β-endorphin （β-EP） levels in rat brain tissue. Western blot technique was used to detect the levels of NLRP3， ASC， Caspase-1， and OTULIN proteins in rat brain tissue. ResultsCompared with the normal group， the pain threshold of rats in the model group showed a continuous significant decrease （P<0.01）. The pathological damage of brain tissue was significant （P<0.01）， and the inflammatory levels of IL-1， IL-6， IL-8， and TNF-α in serum were significantly elevated （P<0.01）. The level of the SP in the brain tissue was significantly elevated （P<0.01）， and the level of β-EP was significantly reduced （P<0.01）， while the level of OTULIN was significantly reduced， and NLRP3， ASC， and Caspase-1 protein levels were significantly elevated （P<0.01）. After administration of the drug， compared with the model group， the pain threshold of each dose group of the Cranial Painkiller pills' extract powder and the Cranial Painkiller granules group significantly increased （P<0.01）. The inflammatory levels of IL-1， IL-6， IL-8， and TNF-α and SP levels significantly decreased （P<0.01）， and the β-EP levels were significantly elevated （P<0.01）， while the levels of OTULIN protein were significantly elevated （P<0.05， P<0.01）， and the levels of NLRP3， ASC proteins were decreased （P<0.01）in high dose Cranial Painkiller pills' extract powder. Meanwhile， compared with those in the model group， the trigeminal ganglion lesions of rats in the Cranial Painkiller pills' extract powder and Cranial Painkiller granules groups showed different degrees of improvement （P<0.05， P<0.01）. ConclusionThe Cranial Painkiller pills' extract powder has significant therapeutic effects on the rat model of trigeminal neuralgia induced by infraorbital injection of Talci Pulvis， and its mechanism is related to the improvement of OTULIN-regulated neuroinflammation.

Objective:To understand the epidemiological characteristics of human respiratory syncytial virus (HRSV) among acute respiratory infection (ARI) cases in 16 provinces of China from 2009 to 2023.Methods:The data of this study were collected from the ARI surveillance data from 16 provinces in China from 2009 to 2023, with a total of 28 278 ARI cases included in the study. The clinical specimens from ARI cases were screened for HRSV nucleic acid from 2009 to 2023, and differences in virus detection rates among cases of different age groups, regions, and months were analyzed.Results:A total of 28 278 ARI cases were enrolled from January 2009 to September 2023. The age of the cases ranged from<1 month to 112 years, and the age M ( Q1, Q3) was 3 years (1 year, 9 years). Among them, 3 062 cases were positive for HRSV nucleic acid, with a total detection rate of 10.83%. From 2009 to 2019, the detection rate of HRSV was 9.33%, and the virus was mainly prevalent in winter and spring. During the Corona Virus Disease 2019 (COVID-19) pandemic, the detection rate of HRSV fluctuated between 6.32% and 18.67%. There was no traditional winter epidemic peak of HRSV from the end of 2022 to the beginning of 2023, and an anti-seasonal epidemic of HRSV occurred from April to May 2023. About 87.95% (2 693/3 062) of positive cases were children under 5 years old, and the difference in the detection rate of HRSV among different age groups was statistically significant ( P<0.001), showing a decreasing trend of HRSV detection rate with the increase of age ( P<0.001). Among them, the HRSV detection rate (25.69%) was highest in children under 6 months. Compared with 2009-2019, the ranking of HRSV detection rates in different age groups changed from high to low between 2020 and 2023, with the age M (Q1, Q3) of HRSV positive cases increasing from 1 year (6 months, 3 years) to 2 years (11 months, 3 years). Conclusion:Through 15 years of continuous HRSV surveillance analysis, children under 5 years old, especially infants under 6 months old, are the main high-risk population for HRSV infection. During the COVID-19 pandemic, the prevalence and patterns of HRSV in China have changed.

ObjectiveTo evaluate the effectiveness of Lutongning granules in the treatment of trigeminal neuralgia in animal models and study its mechanism of action， so as to provide laboratory data support for the clinical application of Lutongning granules and precise treatment. MethodMale SD rats were randomly divided into normal group， model group， carbamazepine group （0.06 g·kg^-1·d^-1）， high-dose Lutongning group （2.70 g·kg^-1·d^-1）， and low-dose Lutongning group （1.35 g·kg^-1·d^-1） according to the stratified basic mechanical pain thresholds， with 10 rats in each group. A trigeminal neuralgia model of rats was prepared by injecting 30% talc suspension into the infraorbital foramen area of the rat. The drug groups were administered 10 mL·kg^-1 of drugs by gavage after 2 h of modeling. The normal group and the model group were administered distilled water by gavage under the same conditions once a day for 10 consecutive days. Von Frey brushes were used to determine the mechanical pain threshold of rats. A fully automated blood and body fluid analyzer was employed to detect the blood routine of rats. Hematoxylin and eosin （HE） staining was utilized to detect the pathological changes in the trigeminal ganglion and medulla oblongata tissue. Transmission electron microscopy was used to scan the ultrastructure of the medulla oblongata tissue. Enzyme-linked immunosorbent assay （ELISA） was used to detect the levels of inflammatory factors interleukin （IL）-1， IL-6， IL-8， tumor necrosis factor （TNF）-α， neuropeptide substance P， and β-endorphins （β-EP） in the serum of rats， and Western blot was used to detect the protein expression levels of IL-1β， purinergic receptor P2X7 （P2X7R）， and phosphorylated p38 mitogen-activated protein kinase （p-p38 MAPK）. ResultCompared with that in the normal group， the pain threshold of rats in the model group was significantly lower （P<0.01）. The absolute value of neutrophils （NEUT#） and the percentage of neutrophils （NEUT） were significantly improved， and the percentage of lymphocytes （LYMPH） was significantly reduced （P<0.01）. The serum levels of IL-1， IL-6， IL-8， and TNF-α were significantly increased （P<0.01）. SP content in brain tissue was significantly increased， and β-EP content was significantly decreased （P<0.01）. The relative protein expression of IL-1β， P2X7R， and p-p38 MAPK was significantly increased （P<0.05）. HE staining and transmission electron microscopy results of medulla oblongata tissue revealed neuronal degeneration， mild proliferation of microglial cells， reduction in the number of myelinated nerves， and obvious demyelination. The trigeminal nerve fibers of rats were disarranged， and some nerve fibers showed vacuolization. Axons were swollen， and Schwann cells proliferated. Demyelination was observed. Compared with the model group， each administration group significantly increased the pain threshold of rats （P<0.05， P<0.01）， reduced NEUT# and NEUT， and elevated LYMPH （P<0.05， P<0.01）. The administration group significantly decreased the levels of IL-1， IL-6， IL-8， and TNF-α in serum and SP in brain tissue （P<0.01） and increased the level of β-EP （P<0.01）. They significantly down-regulated the protein expression of IL-1β， P2X7R， and p-p38 MAPK（P<0.05， P<0.01） and significantly ameliorated the pathological changes in medulla oblongata tissue and trigeminal nerves of rats. ConclusionLutongning Granules had significant therapeutic effects on trigeminal neuralgia induced by injection of talc into the infraorbital foramen of model rats， and the mechanism may be related to amelioration of P2X7R-mediated neuroinflammation and inhibition of demyelination of myelinated nerves.

Objective:To explore the effects of Liuwei Dihuang Wan on the behaviors and Toll-like receptor 4/nuclear factor kappa-B(TLR4/NF-κB) signal transduction pathway of amyloid β-precursor protein/presenilin-1(APP/PS1) double transgenic mice.Methods:Forty 3-month-old female APP/PS1 mice were randomly divided into model group, low-dose group(0.59 g/kg), medium-dose group(1.18 g/kg), high-dose group(2.36 g/kg)of Liuwei Dihuang Wan(gavaged according to grouped doses), and ibuprofen group(0.04 g/kg, gavage) using a random number table method, with 8 mice in each group.Eight 3-month-old wild-type female C57BL/6 mice with matched body weight were used as the control group.The mice in control group and model group were given an equal volume of 0.9% sodium chloride solution by gavage.The gavage administration was twice a day for a continuous period of 3 months.Morris water maze test was used to detect the learning and memory abilities of mice. ELISA was used to detect the serum levels of tumor necrosis factor-α (TNF-α), interleukin-1β(IL-1β) and immunohistochemistry was used to detect the levels of amyloid β-protein (Aβ), glial fibrillary acidic protein(GFAP) and NF-κB in hippocampal tissue.Western blot was used to detect the expression levels of TLR4, myeloid differentiation primary response gene 88(MyD88), and phosphorylated NF-κB(p-NF-κB) proteins in hippocampal tissue.The SPSS 20.0 software was used for data analysis. Multiple group comparisons were conducted by repeated measure ANOVA or one-way ANOVA.Results:The results of repeated measure ANOVA showed that as for the escape latency of the 6 groups of mice, the interaction effect between time and group was significant ( Finteraction=117.219, P<0.001). The escape latencies of mice in the 6 groups on the 5th day were all lower than those on the 1st day (all P<0.05). The escape latencies of mice in the ibuprofen group and the medium-dose and high-dose groups of Liuwei Dihuang Wan were lower than that in the model group from 1st day to 5th day(all P<0.05). On the 3rd to 5th day, the escape latencies of mice in the medium-dose and high-dose groups of Liuwei Dihuang Wan were lower than those in the low-dose group of Liuwei Dihuang Wan (all P<0.05). There were statistically significant differences in the percentage of residence time in the platform quadrant and the numbers of crossing platform among the 6 groups of mice ( F=5.451, 4.824, both P<0.05). The percentage of residence time in the platform quadrant (50.77±5.49)%, (54.39±5.71)%, (51.98±6.12)%), and the numbers of crossing platform((5.9±1.1) times, (6.0±1.3) times, (5.1±0.8) times) in the high-dose and medium-dose groups of Liuwei Dihuang Wan and the ibuprofen group were all higher than those in the model group ((27.32±3.22)%, (2.2±1.0) times )(all P<0.05). The immunohistochemical results showed that there were statistically significant differences in the integrated optical density values of Aβ, GFAP and NF-κB in the hippocampal tissues of 6 groups of mice ( F=57.52, 45.37, 79.10, all P<0.05). The integrated optical density values of Aβ, GFAP and NF-κB in the high-dose and medium-dose groups of Liuwei Dihuang Wan and the ibuprofen group were all lower than those in the model group (all P<0.05). And the integrated optical density values of Aβ, GFAP, and NF-κB in the high-dose and medium-dose groups of Liuwei Dihuang Wan were all lower than those in the low-dose group of Liuwei Dihuang Wan (all P<0.05). There were statistically significant differences in the levels of serum TNF-α and IL-1β detected by ELISA ( F=3.996, 6.395, both P<0.05) and the proteins levels of TLR4, MyD88, and p-NF-κB in hippocampal tissue detected by Western blot among the 6 groups( F=15.710, 3.522, 4.119, all P<0.05). The serum TNF-α and IL-1β levels in the high-dose and medium-dose groups of Liuwei Dihuang Wan and ibuprofen group were all lower than those in the model group (all P<0.05). The serum TNF-α ((18.90±2.33) ng/L, (21.56±2.49) ng/L) and IL-1β ((5.88±0.80) ng/L, (6.75±0.83) ng/L) levels in the high-dose and medium-dose groups of Liuwei Dihuang Wan were lower than those in the low-dose group ((30.77±2.89) ng/L, (9.11±1.27) ng/L) (all P<0.05). The protein expression levels of TLR4, MyD88, and p-NF-κB in the hippocampus of the high-dose and medium-dose groups of Liuwei Dihuang Wan and ibuprofen group were lower than those of the model group (all P<0.05). The protein expression levels of TLR4 ((0.254±0.091), (0.318±0.122)), MyD88 ((0.229±0.077), (0.386±0.119)), and p-NF-κB ((0.412±0.188), (0.358±0.119)) in the hippocampus of the high-dose and medium-dose groups of Liuwei Dihuang Wan were lower than those of the low-dose group ((0.617±0.172), (0.672±0.166), (0.799±0.227)) (all P<0.05). Conclusion:Liuwei Dihuang Wan can significantly alleviate learning and memory impairment in Alzheimer's disease model mice, possibly by inhibiting TLR4/NF-κB signal pathway, reducing TNF-α and IL-1β expression, thereby alleviate central immune inflammatory response and exert anti Alzheimer's disease effects.

Acute cerebral infarction(ACI)has the characteristics of onset nasty and high mortality,and thus the rapid determination of the occurrence and development of ACI plays a key role in the diagnosis,treatment and prognosis of ACI patients.It has shown that the serum level of human haptoglobin(Hp)is related to ACI.In this study,surface enhanced Raman scattering(SERS)combined with immune recognition was applied to establish a quantitative analysis method for serum Hp.Firstly,the SERS substrate of silver nanoparticles was prepared on silicon wafer,and 4-mercaptobenzoic Acid(MBA)was used as a Raman probe by forming Ag—S bond and connecting it on the surface of nanoparticles.The carboxyl group of MBA was linked to amino group of self-made high-affinity antibody through forming CO—NH structure thus forming a SERS self-assembled chip of Hp(Ag/MBA/anti-Hp).Hp in serum could be specifically captured by antibodies on SERS substrate,which caused the shift of SERS characteristic peak of MBA.The results showed that there was a good linear relationship between the logarithm of Hp concentration and the SERS characteristic peak shift of MBA.The detection range was 1-1000 ng/mL(R2=0.988).The Hp concentrations in serum of 90 ACI patients were determined by this method,and the results were consistent with those of ELISA method,which proved the practicability and accuracy of this method.This method was highly specific,simple and convenient,which could realize the specific recognition and quantitative analysis of serum Hp,so as to be an effective means for clinical detection of serum Hp,thus providing a reference for the treatment and prognosis of ACI.

Objective:To understand the epidemiological characteristics of human respiratory syncytial virus (HRSV) among acute respiratory infection (ARI) cases in 16 provinces of China from 2009 to 2023.Methods:The data of this study were collected from the ARI surveillance data from 16 provinces in China from 2009 to 2023, with a total of 28 278 ARI cases included in the study. The clinical specimens from ARI cases were screened for HRSV nucleic acid from 2009 to 2023, and differences in virus detection rates among cases of different age groups, regions, and months were analyzed.Results:A total of 28 278 ARI cases were enrolled from January 2009 to September 2023. The age of the cases ranged from<1 month to 112 years, and the age M ( Q1, Q3) was 3 years (1 year, 9 years). Among them, 3 062 cases were positive for HRSV nucleic acid, with a total detection rate of 10.83%. From 2009 to 2019, the detection rate of HRSV was 9.33%, and the virus was mainly prevalent in winter and spring. During the Corona Virus Disease 2019 (COVID-19) pandemic, the detection rate of HRSV fluctuated between 6.32% and 18.67%. There was no traditional winter epidemic peak of HRSV from the end of 2022 to the beginning of 2023, and an anti-seasonal epidemic of HRSV occurred from April to May 2023. About 87.95% (2 693/3 062) of positive cases were children under 5 years old, and the difference in the detection rate of HRSV among different age groups was statistically significant ( P<0.001), showing a decreasing trend of HRSV detection rate with the increase of age ( P<0.001). Among them, the HRSV detection rate (25.69%) was highest in children under 6 months. Compared with 2009-2019, the ranking of HRSV detection rates in different age groups changed from high to low between 2020 and 2023, with the age M (Q1, Q3) of HRSV positive cases increasing from 1 year (6 months, 3 years) to 2 years (11 months, 3 years). Conclusion:Through 15 years of continuous HRSV surveillance analysis, children under 5 years old, especially infants under 6 months old, are the main high-risk population for HRSV infection. During the COVID-19 pandemic, the prevalence and patterns of HRSV in China have changed.

Objective To systematically evaluate the efficacy and safety of Kangfuxin liquid combined with conventional treatment in postoperative patients with gastrointestinal endoscopy.Methods PubMed,Embase,Cochrane Library,CNKI,WanFang Data,VIP databases were electronically searched to collect randomized controlled trials(RCTs)about Kangfuxin liquid combined with conventional treatment versus conventional treatment for postoperative complications of gastrointestinal endoscopy,from inception to December 31,2023.Two reviewers independently screened literature,extracted data and assessed the risk of bias in the included studies.Meta-analysis was then performed by using RevMan 5.3 software and Stata 14 software.Results A total of 14 RCTs involving 1 359 patients were included.The results of Meta-analysis showed that compared with the conventional treatment group,the Kangfuxin liquid combination group could improve postoperative ulcer complete healing rate(RR=1.32,95％CI 1.07 to 1.61,P=0.009)and postoperative clinical symptomatic relief rate(RR=1.20,95％CI 1.13 to 1.27,P＜0.001),but there was no statistically significant difference in the incidence of adverse reactions between the two groups(P＞0.05).Subgroup analyses showed that the ulcer complete healing rate in the Kangfuxin liquid combination group was higher than that in the conventional treatment group at 2 weeks postoperatively(RR=1.56,95％CI 1.28 to 1.92,P＜0.001),but there was no statistically significant difference in ulcer complete healing rate between the two groups at 4 weeks postoperatively(P＞0.05);the efficacy of oral administration(RR=1.19,95％CI 1.11 to 1.27,P＜0.001)and transendoscopic topical spray administration(RR=1.23,95％CI 1.09 to 1.39,P＜0.001)of Kangfuxin liquid groups were better than those of the conventional treatment group in relieving postoperative clinical symptoms.Conclusion Combining Kangfuxin liquid treatment with conventional medication after gastrointestinal endoscopy may further improve clinical efficacy,especially in promoting the ulcer complete healing within 2 weeks after surgery and relieving postoperative clinical symptoms,but there is insufficient evidence on whether it reduces the incidence of adverse effects.Due to the limitations of the number and quality of included studies,the above conclusions are yet to be validated by more high-quality studies.

Objective To investigate the effects of different sterilization methods on the quality of Astragali Radix decoction pieces by comparing the properties,odor,fingerprint,sterilization effect,extract and active component contents of Astragali Radix decoction pieces,and to further optimize the best sterilization process parameters of Astragali Radix decoction pieces.Methods The effects of moist heat sterilization,irradiation sterilization and dry heat sterilization on the quality of Astragali Radix decoction pieces were compared,and the best sterilization method was selected.Based on this,taking the content of astragaloside IV,the content of isoflavone glucoside,the total content of the two and the sterilization rate as the assessment indicators,taking the sterilization temperature,sterilization time and material thickness as the assessment factors,on the basis of the single-factor test,the response surface method was used to optimize the optimal dry heat sterilization process of Astragali Radix decoction pieces.Results The dry heat sterilization method was selected to sterilize Astragali Radix decoction pieces.The best process for dry heat sterilization was as follows:the sterilization temperature of 113℃,sterilization time of 5.1 h,and the material thickness of 19 mm.Conclusion Considering the sterilization effect,the influence on the content of active ingredients,operability and cost,selecting dry heat sterilization is the best sterilization method for Astragali Radix decoction pieces,and the optimal sterilization process is stable and feasible,with good repeatability,which can provide scientific basis for its industrial production application.