Objective To investigate the frequency and dose of X-ray computed tomography (CT) medical exposure in Shantou City, and to evaluate the collective effective dose burden of residents caused by CT medical exposure. Methods The study subjects were selected using the stratified random sampling method from CT scanners in all medical institutions in Shantou City in 2020. CT application units were divided into the four tiers of municipal hospitals, district hospitals, subdistrict hospitals, and private hospitals, and 50% of the hospitals in each tier were randomly selected according to the number of hospitals in the tier. The study analyzed CT dose index results, CT scanning standard conditions, and the distribution of characteristic doses of medical exposure to evaluate the dose burden of residents in Shantou City caused by CT medical exposure. Results There were 51 CT scanners in medical institutions in Shantou City. By the end of 2020, the average number of CT scanners per million population was 9.30, and the frequency of CT medical exposure was 135.24 per 1000 population. Jinping District had the highest number of CT scanners per million population (23.2), while Chaoyang District had the lowest number of CT scanners per million population (3.6). The median and range of effective doses for different scan regions were 1.65 (0.76, 4.49) mSv in the head, 4.12 (1.90, 53.21) mSv in the chest, 5.96 (2.68, 10.25) mSv in the abdomen, and 10.30 (4.12, 12.67) mSv in the lumbar spine. By the end of 2020, the effective dose to the public in Shantou City was 6080.67 Sv·person, and the average annual effective dose per person was 1.10 mSv. Conclusion Medical exposure is the most important factor affecting resident dose burden, particularly the overuse of medical exposure examinations. CT examination is the most significant component of medical exposure causing resident dose burden. Reducing unnecessary medical exposure, ensuring the rational use of CT examination, and properly utilizing personal protective equipment are effective measures to minimize the dose burden on examinees.

Objective:To understand the clinical characteristics of stenotrophomonas maltophilia（SMA）infections in pediatric patients.Methods:This was a retrospective observational study.The children diagnosed with SMA infections between January 2018 and June 2023 at Shanghai Children's Medical Center were selected as the study population.The clinical characteristics of patients were analyzed.According to the outcome,the patients were categorized into survival and death groups to compare the clinical characteristics.Results:A total of 70 patients were included in the study,including 23 females and 47 males,with an onset age of 9.0 (3.0,12.6) years old.Sixty-five (92.9%) patients had underlying malignancies，primarily hematologic and solid tumors,of which 24(34.3%) cases underwent bone marrow hematopoietic stem cell transplantation,and 18(25.7%) cases underwent chimeric antigen receptor T cell immunotherapy (CAR-T).Forty (57.1%) cases of SMA infection sites were respiratory infections,19 (27.1%) cases were bloodstream infections,and 11 (15.7%) cases were soft tissue infections.Prior to infection，33（47.14%）patients were treated with glucocorticoids and 63（90.0%）patients with carbapenems.Eventually，39（55.7%）patients were discharged,while 31 patients died,with a mortality rate of 44.3%.Minocycline（100.0%），levofloxacin（98.1%），co-trimoxazole（96.2%），and cefoperazone/sulbactam（94.0%）showed high sensitivity rates to SMA.Compared with the survival group,the death group had a younger age [11.9 (8.4,13.8) years vs.6.3 (2.1,10.0) years],longer hospitalization before infection and duration after stem cell transplantation [28 (23,46) d vs.25 (16,34) d,140 (93，221) d vs.24 (12,49) d],and a higher proportion of pre-infection ICU admission,pre-infection glucocorticoids usage,receiving CAR-T treatment and lymphoma as the underlying disease [26 (83.9%) cases vs.15 (38.46%) cases,22 (71.0%) cases vs.11 (28.2%) cases,13 (41.9%) cases vs.5(12.8%) cases,11（35.5%）cases vs.3（7.7%）cases],and the differences were all statistically significant ( P<0.05). Conclusion:SMA infection pose a serious risk to pediatric patients with malignancies,compromised immune systems and exposured to broad-spectrum antibiotics.SMA maintains excellent sensitivity to compound sulfamethoxazole，minocycline，levofloxacin，and cefoperazone/sulbactam in pediatric patients.The mortality rate of SMA infection is very high，with longer pre-infection hospitalization，pre-infection ICU admission，pre-infection glucocorticoids usage，older onset age，longer duration after stem cell transplantation,receiving CAR-T treatment and lymphoma as the underlying disease possibly associated with post infection mortality

Objective:To investigate the pathogens and drug resistance of bacterial enteritis in children, analyze the clinical characteristics of bacterial enteritis in children, and provide basis for clinical diagnosis and treatment.Methods:The fecal culture strain and drug sensitivity of patients with bacterial enteritis admitted to our hospital from January 2016 to December 2020 were analyzed and summarized, and the clinical characteristics of patients who were infected by Salmonella and Escherichia coli were compared.Results:There were a total of 173 patients, aged from 21 days to 15 years, with a median age of 2.00(1.10, 3.54)years.Bacterial enteritis was most likely to occur in summer and autumn, and the incidence rate was 40.5% and 29.5%, respectively.One hundreds and seventy-three strains of bacteria were cultured in feces, including 148 strains of Salmonella(85.5%), 18 strains of Escherichia coli(10.4%), five strains of Staphylococcus aureus and two strains of Shigella.One hundreds and one of 141 patients who were infected with Salmonella were detected for leukocytes of in feces(71.6%), and four of 16 patients with Escherichia coli were detected for leukocytes(25.0%). The difference was significant( χ2=14.1, P<0.001). Eighty-eight of 113 patients(77.9%) who were infected by Salmonella with increased CRP(CRP>8 mg/L)and the proportion in Escherichia coli infection cases was 6/13(46.2%). There was significant difference( χ2=4.63, P=0.03). The drug sensitivity of Salmonella and Escherichia coli was summarized.There was no carbapenem resistant strain cultured; The sensitivity to piperacillin/tazobactam and cefoperazone/sulbactam was higher than 85%; The sensitivity to cefepime, ceftazidimeand ceftriaxone was higher than 75%; The sensitivity to ampicillin was lower than 30%, and the sensitivity to quinolones was between 20%-40%. Conclusion:Children aged 1-3 years are prone to bacterial enteritis in summer and autumn.The most common pathogens causing bacterial enteritis are Salmonella and Escherichia coli.White blood cells are more easily detected in feces of patients with Salmonella infection, and the increase rate of C-reactive protein in peripheral blood is higher.Patients with bacterial enteritis are recommended to use the third-generation cephalosporins and aforementioned antibiotics and piperacillin/tazobactam for empirical treatment.The sensitivity to quinolones is reduced, and may not be suitable for clinical application.

Objective:To investigate the distribution and drug resistance of pathogens in urinary tract infection in children.Methods:The clinical data of 108 cases of urinary tract infections with positive urinary culture from January 2018 to December 2018 in our hospital were analyzed retrospectively.The patients were divided into simple urinary tract infection group( n=29) and complex urinary tract infection group( n=79). Antibiotic resistance in each group was compared. Results:Gram-negative bacilli were found in 90 cases(77.59%, 90/116). Gram-positive cocci were found in 26 cases(22.41%, 26/116). Escherichia coli, Klebsiella pneumoniae and Enterococcus faecium were the main pathogens.Gram-negative bacilli had the lowest resistance rate to amikacin, imipenem and piperacillin/tazobactam(about 10%). The resistance rate of Gram-negative bacilli to furantoin and quinolones was about 20%, while 30% to 40% to the third and fourth generation cephalosporins and their enzymatic preparations.No Gram-positive cocci was found to be resistant to vancomycin and linezolid.The resistance rate of Gram-positive bacteria to streptomycin and furantoin was 0-20%.There was no significant difference in resistance rate of Gram-negative bacteria to common antibiotics between simple urinary tract infection group and complex urinary tract infection group( P>0.05). Conclusion:Gram-negative bacteria are the main pathogens of urinary tract infections.With the change of drug resistance of pathogens, it may be necessary to change the empirical treatment of urinary tract infection.Furantor can be used as a recommendation for the empirical treatment of mild infection.In the past, there may be underestimate of drug resistance of simple urinary tract infection, and further research is needed.

Objective:To investigate the clinical characteristics of pediatric methicillin-resistant Staphylococcus aureus (MRSA) infection and the antibiotic sensitivity of the isolates. Methods:The clinical data of children with MRSA infection and antibiotic sensitivity of the isolates from 11 children′s hospitals in Infectious Diseases Surveillance of Paediatrics (ISPED) group of China between January 1, 2018 and December 31, 2018 were collected retrospectively. The children′s general condition, high-risk factors, antimicrobial therapy and prognosis, differences in clinical disease and laboratory test results between different age groups, and differences of antibiotic sensitivity between community-acquired (CA)-MRSA and hospital-acquired (HA)-MRSA were analyzed. The t test and Wilcoxon rank sum test were used for statistical analysis of the quantitative data and Chi-square test were used for comparison of rates. Results:Among the 452 patients, 264 were males and 188 were females, aged from 2 days to 17 years. There were 233 cases (51.5%) in the ≤1 year old group, 79 cases (17.5%) in the>1-3 years old group, 29 cases (6.4%) in the >3-5 years old group, 65 cases (14.4%) in the >5-10 years old group, and 46 cases (10.2%) in the>10 years old group. The main distributions of onset seasons were 55 cases (12.2%) in December, 47 cases (10.4%) in February, 46 cases (10.2%) in November, 45 cases (10.0%) in January, 40 cases (8.8%) in March. There were 335 cases (74.1%) CA-MRSA and 117 (25.9%) cases HA-MRSA. Among all cases, 174 cases (38.5%) had basic diseases or long-term use of hormone and immunosuppressive drugs. During the period of hospitalization, 209 cases (46.2%) received medical interventions. There were 182 patients (40.3%) had used antibiotics (β-lactams, glycopeptides, macrolides, carbapenems, oxazolones, sulfonamides etc) 3 months before admission. The most common clinical disease was pneumonia (203 cases), followed by skin soft-tissue infection (133 cases), sepsis (92 cases), deep tissue abscess (42 cases), osteomyelitis (40 cases), and septic arthritis (26 cases), suppurative meningitis (10 cases). The proportion of pneumonia in the ≤1 year old group was higher than the >1-3 years old group,>3-5 years old group,>5-10 years old group,>10 years old group (57.5% (134/233) vs. 30.4% (24/79), 31.0% (9/29), 38.5% (25/65), 23.9% (11/46), χ 2=17.374, 7.293, 7.410, 17.373, all P<0.01) The proportion of skin and soft tissue infections caused by CA-MRSA infection was higher than HA-MRSA (33.4% (112/335) vs. 17.9% (21/117), χ 2=10.010, P=0.002), and the proportion of pneumonia caused by HA-MRSA infection was higher than CA-MRSA (53.0% (62/117) vs. 42.1% (141/335), χ 2=4.166, P=0.041). The first white blood cell count of the ≤1 year old group was higher than that children > 1 year old ((15±8)×10 9/L vs. (13±7)×10 9/L, t=2.697, P=0.007), while the C-reactive protein of the ≤1 year old group was lower than the 1-3 years old group,>5-10 years old group,>10 years old group (8.00 (0.04-194.00) vs.17.00 (0.50-316.00), 15.20 (0.23-312.00), 21.79(0.13-219.00) mg/L, Z=3.207, 2.044, 2.513, all P<0.05), there were no significant differences in procalcitonin (PCT) between different age groups (all P>0.05). After the treatment, 131 cases were cured, 278 cases were improved, 21 cases were not cured, 12 cases died, and 10 cases were abandoned. The 452 MRSA isolates were all sensitive to vancomycin (100.0%), linezolid (100.0%), 100.0% resistant to penicillin, highly resistant to erythromycin (85.0%, 375/441), clindamycin (67.7%, 294/434), less resistant to sulfonamides (5.9%, 23/391), levofloxacin (4.5%, 19/423), gentamicin (3.2%, 14/438), rifampicin (1.8%, 8/440), minocycline (1.1%, 1/91). The antimicrobial resistance rates were not significantly different between the CA-MRSA and HA-MRSA groups (all P>0.05). Conclusions:The infection of MRSA is mainly found in infants under 3 years old. The prevalent seasons are winter and spring, and MRSA is mainly acquired in the community. The main clinical diseases are pneumonia, skin soft-tissue infection and sepsis. No MRSA isolate is resistant to vancomycin, linezolid. MRSA isolates are generally sensitive to sulfonamides, levofloxacin, gentamicin, rifampicin, minocycline, and were highly resistant to erythromycin and clindamycin. To achieve better prognosis. clinicians should initiate anti-infective treatment for children with MRSA infection according to the clinical characteristics of patients and drug sensitivity of the isolates timely and effectively.

Objective To investigate the incidence of Acinetobacter baumannii induced paediatric bacterial meningitis and to explore the characteristics,treatment,and prognosis of Acinetobacter baumannii menin-gitis. Methods The cerebrospinal fluid specimens and the clinical data about patients who acquired intracranial infection of Acinetobacter baumannii were collected from 10 children′s hospital,and analysed by WHONET. Results A total of 318 positive cerebrospinal fluid specimens from 10 hospitals were collected,and 16(5%) of Acinetobacter baumannii were detected. Acinetobacter baumannii was completely resistant to Aztreonam (100%),Cefotetan(100%) and Cefazolin(100%),and the resistance rates of Acinetobacter baumannii to Ceftriaxone and Ciprofloxacin were above 80%,and the resistance rates of Acinetobacter baumannii to Cefta-zidime and Cefepime were all 68. 8%,and the resistance rates of Acinetobacter baumannii to Meropenem, Imipenem,Cefoperazone/Sulbactam were 69. 2%,68. 8% and 53. 3%,respectively. In 16 cases of intracrani-al infection caused by Acinetobacter baumannii,11 cases(68. 8%) had underlying diseases such as intracrani-al tumor,hydrocephalus,craniocerebral injury and intracranial hemorrhage,and all 11 cases underwent surgi-cal intervention,such as surgical resection and hydrocephalus drainage. Among 16 cases,14 cases(87. 5%) were admitted to SICU,PICU or NICU and other intensive care units,and the lengths of stay were all ＞20 d. Under the combined treatment of multiple antibiotics,16 cases of intracranial infection caused by Acinetobact-er baumannii,6 cases died,with a mortality of 37. 5%. Conclusion Acinetobacter baumannii meningitis is becoming an increasingly common clinical entity recently. Because of the resistance to antibiotics,the therapy for Acinetobacter baumannii infection encounters arduous challenge. Insisting on multi-center monitoring and using antibiotics reasonably and effectively appears to be particularly important.

Objective To explore the optimal storage standard of fresh human milk, and to observe the influence of different cold storage condition (time-temperature) on macronutrients (fat, protein, carbohydrates, TS and energy), immune sub-stances (sIgA, lactoferrin, IL-6, 8, 10 and TNF-α) and bacteria indicators of fresh human milk.Methods Fresh milk samples (n=30) were divided and stored at three temperature and nine time points, which are 4℃ (24 h, 48 h, 72 h), -18℃(72 h, 7 d, 14 d, 4 w, 8 w, 12 w), and -80℃ (12 w, 24 w). At each time point, the macronutrients , immune substance, and bacteria colony counts of each milk sample were measured and compared with fresh milk. Results Compared with fresh milk, all indicators with the exception of lactoferrin in stored human milk showed signiifcant difference (P<0.05). Under 4℃ refrigeration condition, fat, IL-6, and TNF-α decreased, bacteria colony counts and Gram-positive colony counts increased over 72 h storage (P<0.05). Under-18℃ freezing condition, fat, protein, TS, energy and IL-6 decreased from 72 h to 12 w storage (P<0.05); carbohydrates and sIgA also decreased from 4 w and 8 w storage, respectively (P<0.05). Under -80℃ freezing condition, fat, protein, TS, energy and IL-6 decreased over 24 W storage (P<0.05).Conclusions The macronutrients, immune substance, and bacteria indicators of human milk were affected obviously by cold storage. Refrigerated at 4℃ should not be longer than 72 h, -80℃ freezing condition should be chosen for more than two months storage.

[Summary] The paper reported perioperative respiratory nursing experience of 31 patients with emphysema complicating pneumothorax treated with lung volume reduction surgery under video-assisted thoracoscopy .The thoracoscopic surgery was completed in 27 patients and conventional thoracotomy were required in 4 patients because of severe pleural cavity adhesions .No severe respiratory complications occurred in all the patients .We deemed that positive preoperative mental nursing , respiratory preparation and exercises, proper physical training , intraoperative prevention of hazardous inhalation , postoperative effective analgesia , and careful management of closed thoracic drainage are key points of perioperative nursing .

Objective To investigate the treatment method of osteoporotic refracture after vertebroplasty.Methods One hundred and twenty patients (140 vertebraes) with osteoporotic fractures from January 2010 to January 2011 were selected,12 months after operation,15 cases of refracture (20vertebraes) patients as the research object,11 cases were given bone cement to strengthen treatment,postoperative anti-infection,recovery given a positive rehabilitation exercise instruction ;4 cases were given anti-osteoporosis treatment.Follow-up of 10 months,whether leakage of bone cement and the recovery of anti-osteoporosis treatment were observed.Results Eleven patients with refracture in the process of bone cement injection had no prevertebral venous leakage and disc leakage,none of the patients had bone cement leakage after operation;including 3 cases occurred back pain after injection,the main consideration was surgery influenced the local nerve functions and given analgesic treatment,then pain significantly reduced; 4cases with anti-osteoporosis therapy and recoverd better,no pain and other unsuitable symptom occurred.Postoperative 3 d all of the patients could get out of bed,were discharged on 1 week after operation.All patients were not appear the adverse host reaction of fillers,with no occurrence of refracture.Through visual analog pain scale(VAS) score,VAS score in the 3 d after treatment and end-stage follow-up were significantly lower than before treatment [(3.05 ± 0.55),(0.05 ± 0.15) scores vs.(6.95 ± 0.65) scores],and VAS score at the time of end-stage follow-up was lower than 3 d after treatment,there was significant difference (P ＜0.05).Conclusion Bone cement to strengthen with anti-infection and rehabilitation exercise instruction and anti-osteoporosis in the treatment of osteoporotic refracture after vertebroplasty curative effect,safe and reliable effect,worthy of clinical popularization and application.

Objective To investigate the mecbanism of safflor injection treating myocardial contusion following thoracic impact.Methods Thirty healthy Japan big-ear rabbits were randomly assigned to the myocardial contusion control group (control group,n =15) and safflor injection group (safflor group,n =15).The rabbits with severe myocardial contusion were induced by BIM-Ⅱ Horizontal Bioimpact Machine.Blood samples were taken from common carotid artery of both groups to measure the levels of plasma thromboxance A2 (TXA2) and prostaglandin I2 ( PGI2 ) at 10 minutes before impact and at t0 minutes,30 minutes,1,3,6,12 and 24 hours after impact.Rabbits were dissected to observe the gross and micropathological changes of the hern at 24 hours after impact.Results The control group showed a distinct falling of plasma PGI2 concentration and a significant increase of plasma TXA2 concentration in the early period after severe myocardial contusion.The morphological observation revealed severe myocardial tissue injury as well.However,the safflor group showed insignificant variation pertaining to the reduction of plasma PGI2 concentration and increase of plasma TXA2 concentration,but obvious alleviation of myocardial tissue injury,as compared with the control group.Meanwhile,the ratio of TXB2 to 6- Ketoprostaglandin Fla (6-Keto-PGFla) in the safflor group was lower than that of the control group (P ＜0.05).Conclusion Safflor injection has therapeutic effect on myocardial contusion by elevating the concentration of plasma PGI2 and decreasing the concentration of plasma TXA2 in the early period after severe myocardial contusion.