ObjectiveTo explore the mechanism of total saponins of Dioscoreae Nipponicae Rhizoma （TSDN） in treating gouty arthritis （GA） by regulating cyclooxygenase-2 （COX-2）-mediated M1 macrophage reprogramming by in vivo and in vitro experiments. MethodsIn vivo experiment： 24 male SD rats were randomly allocated into blank， model （GA）， TSDN， and celecoxib groups， with 6 rats in each group. After 7 days of administration， pathological changes in the ankle synovial tissue were observed via hematoxylin-eosin （HE） staining. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was used to quantify the mRNA levels of NOD-like receptor protein 3 （NLRP3） inflammasome， apoptosis-associated speck-like protein （ASC）， Caspase-1， COX-2， interleukin-1β （IL-1β）， and tumor necrosis factor-α （TNF-α） in the synovial tissue. Enzyme-linked immunosorbent assay （ELISA） was employed to measure the serum levels of inducible nitric oxide synthase （iNOS）， IL-1β， CD86， CD80， CD206， and arginase-1 （Arg-1）. In vitro experiment： The GA model was established by lipopolysaccharide （LPS） + MSU induction， and the inhibitor concentration was screened by the methyl thiazolyl tetrazolium （MTT） assay. RAW264.7 cells were allocated into blank， model， TSDN， dexamethasone， COX-2 inhibitor （celecoxib）， and TSDN + COX-2 inhibitor groups. The levels of iNOS， IL-1β， CD86， CD80， CD206， and Arg-1 in the cell supernatant of each group were determined by enzyme-linked immunosorbent assay （ELISA）. The mRNA and protein levels of NLRP3 inflammasome， COX-2， IL-1β， and TNF-α in each group were determined by Real-time PCR and Western blot， respectively. ResultsIn vivo experiment： compared with the model group， TSDN reduced the mRNA levels of NLRP3 inflammasome， COX-2， IL-1β， and TNF-α in the synovial tissue （P<0.05， P<0.01）. ELISA results showed that TSDN lowered the serum levels of iNOS， IL-1β， CD86， and CD80 （P<0.01） while increasing the serum levels of CD206 and Arg-1 （P<0.01）. In vitro experiment： compared with the model group， TSDN and inhibitor down-regulated the mRNA levels of NLRP3 inflammasome， COX-2， IL-1β， and TNF-α and the protein levels of NLRP3 inflammasome， COX-2， cleaved IL-1β， and TNF-α （P<0.01）. Compared with TSDN alone， TSDN + COX-2 inhibitor further reduced the mRNA and protein levels of the markers above （P<0.01）. Compared with the model group， TSDN and COX-2 inhibitor decreased the levels of IL-1β， iNOS， CD80， and CD86 （P<0.01） and increased the levels of CD206 and Arg-1 （P<0.01） in cells. Compared with TSDN alone， TSDN + COX-2 inhibitor reduced IL-1β， iNOS， CD80， and CD86 levels （P<0.05， P<0.01） and elevated CD206 and Arg-1 levels （P<0.01） in cells. ConclusionTSDN can alleviate GA by downregulating COX-2-mediated M1 macrophage reprogramming and suppressing the inflammatory factors.

ObjectiveTo explore the mechanism of total saponins of Dioscoreae Nipponicae Rhizoma （TSDN） in treating gouty arthritis （GA） by regulating cyclooxygenase-2 （COX-2）-mediated M1 macrophage reprogramming by in vivo and in vitro experiments. MethodsIn vivo experiment： 24 male SD rats were randomly allocated into blank， model （GA）， TSDN， and celecoxib groups， with 6 rats in each group. After 7 days of administration， pathological changes in the ankle synovial tissue were observed via hematoxylin-eosin （HE） staining. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was used to quantify the mRNA levels of NOD-like receptor protein 3 （NLRP3） inflammasome， apoptosis-associated speck-like protein （ASC）， Caspase-1， COX-2， interleukin-1β （IL-1β）， and tumor necrosis factor-α （TNF-α） in the synovial tissue. Enzyme-linked immunosorbent assay （ELISA） was employed to measure the serum levels of inducible nitric oxide synthase （iNOS）， IL-1β， CD86， CD80， CD206， and arginase-1 （Arg-1）. In vitro experiment： The GA model was established by lipopolysaccharide （LPS） + MSU induction， and the inhibitor concentration was screened by the methyl thiazolyl tetrazolium （MTT） assay. RAW264.7 cells were allocated into blank， model， TSDN， dexamethasone， COX-2 inhibitor （celecoxib）， and TSDN + COX-2 inhibitor groups. The levels of iNOS， IL-1β， CD86， CD80， CD206， and Arg-1 in the cell supernatant of each group were determined by enzyme-linked immunosorbent assay （ELISA）. The mRNA and protein levels of NLRP3 inflammasome， COX-2， IL-1β， and TNF-α in each group were determined by Real-time PCR and Western blot， respectively. ResultsIn vivo experiment： compared with the model group， TSDN reduced the mRNA levels of NLRP3 inflammasome， COX-2， IL-1β， and TNF-α in the synovial tissue （P<0.05， P<0.01）. ELISA results showed that TSDN lowered the serum levels of iNOS， IL-1β， CD86， and CD80 （P<0.01） while increasing the serum levels of CD206 and Arg-1 （P<0.01）. In vitro experiment： compared with the model group， TSDN and inhibitor down-regulated the mRNA levels of NLRP3 inflammasome， COX-2， IL-1β， and TNF-α and the protein levels of NLRP3 inflammasome， COX-2， cleaved IL-1β， and TNF-α （P<0.01）. Compared with TSDN alone， TSDN + COX-2 inhibitor further reduced the mRNA and protein levels of the markers above （P<0.01）. Compared with the model group， TSDN and COX-2 inhibitor decreased the levels of IL-1β， iNOS， CD80， and CD86 （P<0.01） and increased the levels of CD206 and Arg-1 （P<0.01） in cells. Compared with TSDN alone， TSDN + COX-2 inhibitor reduced IL-1β， iNOS， CD80， and CD86 levels （P<0.05， P<0.01） and elevated CD206 and Arg-1 levels （P<0.01） in cells. ConclusionTSDN can alleviate GA by downregulating COX-2-mediated M1 macrophage reprogramming and suppressing the inflammatory factors.

Objective: To investigate the status quo and associated factors of drinking water knowledge, attitude and behavior among primary school students in rural areas, so as to provide evidence for health behavioral intervention of drinking water in primary school. Methods: Twentythree primary schools in rural area from Hebei, Henan, Shandong and Shanxi provinces were selected by using purposive sampling method from March 1 to April 27 in 2023. Selfdesigned questionnaires regarding knowledge, attitude and behavior of drinking water were distributed to all students in grade 3-6, and 2 173 valid questionnaires were obtained. Multivariate Logistic regression was used to analyze the influencing factors of drinking water knowledge, attitude and behavior of primary school students. Results: The attainment rates of drinking water knowledge, attitude and behavior level were 20.02%, 26.65%, and 31.20%, respectively, among primary school students. The median of daily water intake was 1 000 mL, and the average daily water intake was (1 172.99±771.89)mL. In addition, 66.31% of students water intake reached the minimum standard of 800 mL recommended. The results of multiple Logistic regression indicated that drinking water accessibility in school, health education of drinking water, and individual selfcontrol ability were positively correlated with the knowledge (OR=1.31, 1.57, 1.58), attitude (OR=2.07, 1.65, 1.73), behavior (OR=1.40, 1.49, 1.91) of drinking water and daily water intake (OR=1.41, 1.38, 1.20) (P<0.05). Conclusions Primary school students in rural areas are generally lack of appropriate health awareness on drinking water including knowledge, attitude and behavior. Schools should take targeted measures to focus on the cultivation of students selfcontrol ability, so as to improve students knowledge and attitudes of drinking water, and furthermore help students shape their healthy behaviors of drinking water.

Animal experiments are an essential component of life sciences and medical research. However, the external validity and reliability of individual animal studies are frequently challenged by inherent limitations such as small sample sizes, high design heterogeneity, and poor reproducibility, which impede the effective translation of research findings into clinical practice. Systematic reviews and meta-analysis represent a key methodology for integrating existing evidence and enhancing the robustness of conclusions. Currently, however, the application of systematic reviews and meta-analysis in the field of animal experiments lacks standardized guidelines for their conduct and reporting, resulting in inconsistent quality and, to some extent, diminishing their evidence value. To address this issue, this paper aims to systematically delineate the reporting process for systematic reviews and meta-analysis of animal experiments and to propose a set of standardized recommendations that are both scientific and practical. The article's scope encompasses the entire process, from the preliminary preparatory phase [including formulating the population， intervention， comparison and outcome （PICO） question, assessing feasibility, and protocol pre-registration] to the key writing points for each section of the main report. In the core methods section, the paper elaborates on how to implement literature searches, establish eligibility criteria, perform data extraction, and assess the risk of bias, based on the Preferred Reporting Items for Systematic Reviews and Meta-analysis （PRISMA) statement, in conjunction with relevant guidelines and tools such as Animal Research： Reporting of in Vivo Experiments （ARRIVE) and a risk of bias assessment tool developed by the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE). For the presentation of results, strategies are proposed for clear and transparent display using flow diagrams and tables of characteristics. The discussion section places particular emphasis on how to scientifically interpret pooled effects, thoroughly analyze sources of heterogeneity, evaluate the impact of publication bias, and cautiously discuss the validity and limitations of extrapolating findings from animal studies to clinical settings. Furthermore, this paper recommends adopting the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology to comprehensively grade the quality of evidence. Through a modular analysis of the entire reporting process, this paper aims to provide researchers in the field with a clear and practical guide, thereby promoting the standardized development of systematic reviews and meta-analysis of animal experiments and enhancing their application value in scientific decision-making and translational medicine.

ObjectiveThis study aims to investigate the effect of Dictamni Cortex on intestinal barrier damage in rats and its mechanism by untargeted metabolomics and targeted metabolomics for short-chain fatty acids （SCFAs）. MethodsRats were randomly divided into a control group， a high-dose group of Dictamni Cortex （8.1 g·kg^-1）， a medium-dose group （2.7 g·kg^-1）， and a low-dose group （0.9 g·kg^-1）. Except for the control group， the other groups were administered different doses of Dictamni Cortex by gavage for eight consecutive weeks. Hematoxylin-eosin （HE） staining was used to observe the pathological changes in the ileal tissue. Enzyme-linked immunosorbent assay （ELISA） was employed to detect the level of cytokines， including tumor necrosis factor-α （TNF-α）， interleukin-6 （IL-6）， and interleukin-1β （IL-1β）， in the ileal tissue of rats. Quantitative real-time fluorescence polymerase chain reaction （Real-time PCR） technology was used to detect the expression level of tight junction proteins， including zonula occludens-1 （ZO-1）， Occludin， and Claudin-1 mRNAs， in the ileal tissue of rats to preliminarily explore the effects of Dictamni Cortex on intestinal damage. The dose with the most significant toxic phenotype was selected to further reveal the effects of Dictamni Cortex on the metabolic profile of ileal tissue in rats by non-targeted metabolomics combined with targeted metabolomics for SCFAs. ResultsCompared with the control group， all doses of Dictamni Cortex induced varying degrees of pathological damage in the ileum， increased TNF-α （P<0.01）， IL-6 （P<0.01）， and IL-1β （P<0.01） levels in the ileal tissue， and decreased the expression level of ZO-1 （P<0.05， P<0.01）， Occludin （P<0.01）， and Claudin-1 （P<0.05） in the ileal tissue， with the high-dose group showing the most significant toxic phenotypes. The damage mechanisms of the high-dose group of Dictamni Cortex on the ileal tissue were further explored by integrating non-targeted metabolomics and targeted metabolomics for SCFAs. The non-targeted metabolomics results showed that 21 differential metabolites were identified in the control group and the high-dose group. Compared with that in the control group， after Dictamni Cortex intervention， the level of 14 metabolites was significantly increased （P<0.05， P<0.01）， and the level of seven metabolites was significantly decreased （P<0.05， P<0.01） in the ileal contents. These metabolites collectively acted on 10 related metabolic pathways， including glycerophospholipids and primary bile acid biosynthesis. The quantitative data of targeted metabolomics for SCFAs showed that Dictamni Cortex intervention disrupted the level of propionic acid， butyric acid， acetic acid， caproic acid， isobutyric acid， isovaleric acid， valeric acid， and isocaproic acid in the ileal contents of rats. Compared with those in the control group， the level of isobutyric acid， isovaleric acid， and valeric acid were significantly increased， while the level of propionic acid， butyric acid， and acetic acid were significantly decreased in the ileal contents of rats after Dictamni Cortex intervention （P<0.05， P<0.01）. ConclusionDictamni Cortex can induce intestinal damage by regulating glycerophospholipid metabolism， primary bile acid biosynthesis， and metabolic pathways for SCFAs.

ObjectiveTo explore the mechanism of action of Wuwei Shenqintang in improving pulmonary fibrosis by using ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry （UPLC-Q-TOF-MS） for metabolomic analysis of lung tissue and feces. MethodsA rat model with pulmonary fibrosis was established by intratracheal injection of 5 mg·kg^-1 bleomycin. The successfully modeled rats were randomly divided into a blank group， a model group， a prednisone （3.15 mg·kg^-1） group， and low-dose， medium-dose， and high-dose groups of Wuwei Shenqintang （4.586， 9.172， 18.344 g·kg^-1）. The rats were given intragastric administration once a day for 28 consecutive days. Hematoxylin-eosin （HE） staining was used to measure the pathological changes in lung and colon tissue， and Masson staining was used to detect the degree of pulmonary fibrosis. Enzyme-linked immunosorbent assay （ELISA） was used to detect the expression of interleukin-1β （IL-1β）， IL-6， IL-8， tumor necrosis factor-α （TNF-α）， and secretory immunoglobulin A （SIgA） in bronchoalveolar lavage fluid and intestinal mucus. Immunohistochemistry and reverse transcription quantitative polymerase chain reaction （Real-time PCR） were used to detect the expression of type Ⅰ collagen （Col-Ⅰ）， fibronectin （FN）， and alpha smooth muscle actin （α-SMA） in lung tissue. UPLC-Q-TOF-MS was used to study the changes in the metabolic network of lung tissue and feces in rats with pulmonary fibrosis treated with Wuwei Shenqintang， screen potential biomarkers for the treatment of pulmonary fibrosis by Wuwei Shenqintang， and perform pathway enrichment analysis. ResultsCompared with the blank group， the model group showed extensive inflammatory cell infiltration and continuous fibrotic lesions in lung tissue， colonic mucosal damage， and connective tissue hyperplasia. The expression of IL-6， IL-8， IL-1β， TNF-α， and SIgA in bronchoalveolar lavage fluid and intestinal mucus was significantly increased （P<0.01）. The expression of Col-Ⅰ， FN， and α-SMA proteins and mRNAs in lung tissue was significantly upregulated （P<0.01）. Compared with the model group， the groups of Wuwei Shenqintang exhibited significantly reduced inflammatory infiltration and blue collagen deposition in lung tissue， alleviated colonic damage， decreased expression of IL-6， IL-8， IL-1β， TNF-α， and SIgA in bronchoalveolar lavage fluid and intestinal mucus （P<0.01）， and reduced average absorbance values and mRNA expression of Col-Ⅰ， FN， and α-SMA in lung tissue （P<0.05， P<0.01）， with the prednisone group and the medium-dose and high-dose groups of Wuwei Shenqintang showing the most significant effects. The metabolomics results for lung tissue showed that compared with the blank group， the model group had 19 significantly different compounds （P<0.05， P<0.01）. Wuwei Shenqintang could normalize 17 of these compounds compared with the model group （P<0.05， P<0.01）. Fecal metabolomics results showed that compared with those in the blank group， there were 42 compounds with significant differences in the model group （P<0.05， P<0.01）. Compared with the model control group， Wuwei Shenqintang could normalize 41 of these compounds （P<0.05， P<0.01）. The combined analysis results indicated that Wuwei Shenqintang might inhibit pulmonary fibrosis by regulating the biosynthesis of phenylalanine， tyrosine， and tryptophan as well as the retinol metabolism pathway. ConclusionWuwei Shenqintang can ameliorate pulmonary fibrosis， which may be related to the regulation of the "lung-intestine axis".

ObjectiveTo explore the mechanism of action of Wuwei Shenqintang in improving pulmonary fibrosis by using ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry （UPLC-Q-TOF-MS） for metabolomic analysis of lung tissue and feces. MethodsA rat model with pulmonary fibrosis was established by intratracheal injection of 5 mg·kg^-1 bleomycin. The successfully modeled rats were randomly divided into a blank group， a model group， a prednisone （3.15 mg·kg^-1） group， and low-dose， medium-dose， and high-dose groups of Wuwei Shenqintang （4.586， 9.172， 18.344 g·kg^-1）. The rats were given intragastric administration once a day for 28 consecutive days. Hematoxylin-eosin （HE） staining was used to measure the pathological changes in lung and colon tissue， and Masson staining was used to detect the degree of pulmonary fibrosis. Enzyme-linked immunosorbent assay （ELISA） was used to detect the expression of interleukin-1β （IL-1β）， IL-6， IL-8， tumor necrosis factor-α （TNF-α）， and secretory immunoglobulin A （SIgA） in bronchoalveolar lavage fluid and intestinal mucus. Immunohistochemistry and reverse transcription quantitative polymerase chain reaction （Real-time PCR） were used to detect the expression of type Ⅰ collagen （Col-Ⅰ）， fibronectin （FN）， and alpha smooth muscle actin （α-SMA） in lung tissue. UPLC-Q-TOF-MS was used to study the changes in the metabolic network of lung tissue and feces in rats with pulmonary fibrosis treated with Wuwei Shenqintang， screen potential biomarkers for the treatment of pulmonary fibrosis by Wuwei Shenqintang， and perform pathway enrichment analysis. ResultsCompared with the blank group， the model group showed extensive inflammatory cell infiltration and continuous fibrotic lesions in lung tissue， colonic mucosal damage， and connective tissue hyperplasia. The expression of IL-6， IL-8， IL-1β， TNF-α， and SIgA in bronchoalveolar lavage fluid and intestinal mucus was significantly increased （P<0.01）. The expression of Col-Ⅰ， FN， and α-SMA proteins and mRNAs in lung tissue was significantly upregulated （P<0.01）. Compared with the model group， the groups of Wuwei Shenqintang exhibited significantly reduced inflammatory infiltration and blue collagen deposition in lung tissue， alleviated colonic damage， decreased expression of IL-6， IL-8， IL-1β， TNF-α， and SIgA in bronchoalveolar lavage fluid and intestinal mucus （P<0.01）， and reduced average absorbance values and mRNA expression of Col-Ⅰ， FN， and α-SMA in lung tissue （P<0.05， P<0.01）， with the prednisone group and the medium-dose and high-dose groups of Wuwei Shenqintang showing the most significant effects. The metabolomics results for lung tissue showed that compared with the blank group， the model group had 19 significantly different compounds （P<0.05， P<0.01）. Wuwei Shenqintang could normalize 17 of these compounds compared with the model group （P<0.05， P<0.01）. Fecal metabolomics results showed that compared with those in the blank group， there were 42 compounds with significant differences in the model group （P<0.05， P<0.01）. Compared with the model control group， Wuwei Shenqintang could normalize 41 of these compounds （P<0.05， P<0.01）. The combined analysis results indicated that Wuwei Shenqintang might inhibit pulmonary fibrosis by regulating the biosynthesis of phenylalanine， tyrosine， and tryptophan as well as the retinol metabolism pathway. ConclusionWuwei Shenqintang can ameliorate pulmonary fibrosis， which may be related to the regulation of the "lung-intestine axis".

Objective:By analyzing the cost change trend,internal structure change and main influencing factors of diabetes inpatients'hospitalization expenses,it provides empirical basis for promoting the reform of medical service prices,optimizing the internal structure of hospitalization expenses,effectively controlling hospitalization expenses,and reducing the economic burden of diabetes inpatients.Methods:Using the first page data of medical records of 13 426 diabetes inpatients in the target hospital from 2017 to 2021,it analyzes the structural change of diabetes inpatients'hospitalization expenses by using structural change degree and grey correlation degree methods,and analyzes the influencing factors of hospitalization expenses by using linear regression and BP neural network model.Results:Drug expenses and medical technology expenses are the top two in the proportion of total hospitalization expenses of discharged patients with diabetes,and they account for a large proportion in the total hospitalization expenses.The results of structural change and grey correlation show that drug expenses and medical technology expenses are these two factors that cause changes in the total hospitalization cost structure and have a high correlation with the total hospitalization cost,with a cumulative contribution rate of 90.50％.According to the results of linear regression and neural network model,the length of stay is the most important factor affecting the total cost of hospitalization of diabetes patients,followed by the number of operations/procedures and diagnoses.Conclusion:The internal composition of hospitalization expenses for diabetes patients is unreasonable.The proportion of drug expenses and medical technology expenses is too high.The proportion of medical and nursing expenses reflecting the technical labor value of medical personnel is relatively low.The structure of medical income needs to be further optimized.The length of stay is the most critical factor affecting the hospitalization expenses of diabetes patients.Reasonable control of the length of stay can effectively control the unreasonable growth of medical expenses and reduce the economic burden of diabetes patients.

Objective To investigate the effect of propofol on pyroptosis and A549 cells via the NLRP3/ASC/caspase-1 pathway.Methods Establish a three-dimensional culture model of A549 tumor cells using ultra-low attachment plates,A549 cells were cultured using ultra-low adsorption culture plates to establish a three-dimensional culture model.The CCK-8 method was used to detect the effect of propofol on A549 cell proliferation;the inflammatory factors interleukin(IL)-18,IL-1β,and IL-6 were detected in the A549 lung cancer cell supernatants using enzyme-linked immunosorbent assays;western blotting was used to detect the expression levels of pyrolysis-asso-ciated proteins NLRP3,ASC,caspase-1,GSDMD-N,and IL-1β in A549 lung cancer cells in each group.Results Compared to the blank control group,the survival rate of A549 cells in low,medium,and high concentrations of propofol in each group decreased in turn(P＜0.05);the levels of inflammatory factors IL-18,IL-1β,and IL-6 in the A549 cell supernatant,and scorch related protein NLRP3,ASC,caspase-1,GSDMD-N,and IL-1β increased with the increased propofol concentrations(P＜0.05).Conclusion The three-dimensional culture model of lung cancer A549 cells was successfully established using the ultra-low adsorption culture method.Propofol can promote cell apoptosis and inhibit the pyroptosis of A549 lung cancer cells via activating the NLRP3/ASC/caspase-1 pathway.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of national bloodstream infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:During the study period，9 035 strains of Gram-negative bacteria were collected from 51 hospitals，of which 7 895（87.4%）were Enterobacteriaceae and 1 140（12.6%）were non-fermenting bacteria. The top 5 bacterial species were Escherichia coli（ n=4 510，49.9%）， Klebsiella pneumoniae（ n=2 340，25.9%）， Pseudomonas aeruginosa（ n=534，5.9%）， Acinetobacter baumannii complex（ n=405，4.5%）and Enterobacter cloacae（ n=327，3.6%）. The ESBLs-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus spp. were 47.1%（2 095/4 452），21.0%（427/2 033）and 41.1%（58/141），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（58/4 510）and 13.1%（307/2 340）；62.1%（36/58）and 9.8%（30/307）of CREC and CRKP were resistant to ceftazidime/avibactam combination，respectively. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 59.5%（241/405），while less than 5% of Acinetobacter baumannii complex was resistant to tigecycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 18.4%（98/534）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of main Gram-negative bacteria resistance among different regions，with statistically significant differences in the prevalence of CRKP and CRPA（ χ2=20.489 and 20.252， P<0.001）. The prevalence of CREC，CRKP，CRPA，CRAB，ESBLs-producing Escherichia coli and Klebsiella pneumoniae were higher in provinicial hospitals than those in municipal hospitals（ χ2=11.953，81.183，10.404，5.915，12.415 and 6.459， P<0.01 or <0.05），while the prevalence of CRPA was higher in economically developed regions（per capita GDP ≥ 92 059 Yuan）than that in economically less-developed regions（per capita GDP <92 059 Yuan）（ χ2=6.240， P=0.012）. Conclusions:The proportion of Gram-negative bacteria in bloodstream infections shows an increasing trend，and Escherichia coli is ranked in the top，while the trend of CRKP decreases continuously with time. Decreasing trends are noted in ESBLs-producing Escherichia coli and Klebsiella pneumoniae. Low prevalence of carbapenem resistance in Escherichia coli and high prevalence in CRAB complex have been observed. The composition ratio and antibacterial spectrum of bloodstream infections in different regions of China are slightly different，and the proportion of main drug resistant bacteria in provincial hospitals is higher than those in municipal hospitals.