摘要
Objective To design a mobile personnel radiation protection equipment for operation in environments with high radiation such as spent fuel reprocessing plants, to achieve simultaneous protection against γ radiation, neutron radiation, and radioactive aerosol, to reduce the internal and external exposure dose of radioactive workers, and to meet the requirement of operation for two hours. Methods The core parts of the mobile personnel radiation protection equipment included a shielding chamber and a respiratory maintenance system. An automated chassis was used for the movement and lifting of the shielding chamber. MCNP software was used to simulate and calculate the protective effects of shielding chamber made of different materials and material thicknesses. Experimental verification of the shielding chamber design was conducted. Mathematical models were established to describe the variations in the content of various gases in the chamber with personnel operation time. A respiratory maintenance system, a harmful gas absorption device, and an automated mobile chassis were designed. Results The shielding chamber made of polyethylene with a thickness of 80 mm achieved an 80% neutron shielding rate. The respiratory maintenance system could support workers for 2 hours of operation inside the equipment. The mobile chassis allowed operation of the equipment with one person. Conclusion This mobile personnel radiation protection equipment can solve the problem in simultaneous protection against γ radiation, neutron radiation, and radioactive aerosol. The equipment can provide radiation protection for radioactive workers, reduce exposure dose, and reduce personnel burden. This system provides technical means for the operation and maintenance of equipment in high-radiation sites such as spent fuel reprocessing plants.
摘要
Objective·To explore the correlation between comorbidities of chronic non-communicable diseases(chronic diseases),phase angle(PhA),and muscle mass decline associated with sarcopenia in the elderly,and the predictive value of chronic disease comorbidities and PhA in muscle mass decline in the elderly.Methods·By retrospectively screening inpatients aged≥60 years who were admitted to the Department of Geriatrics,Renji Hospital,Shanghai Jiao Tong University School of Medicine from August 1,2018 to July 31,2019,basic information and medical history of the patients(gender,age,number of medications used,number of comorbidities,presence of osteoporosis,smoking history,etc.)were collected,as well as laboratory examination indicators(hemoglobin,albumin,serum creatinine,serum uric acid,ferritin,vitamin D,triacylglycerol,total cholesterol,high-density lipoprotein,low-density lipoprotein,etc.).The age-adjusted Charlson comorbidity index(aCCI)was calculated.The InBody S10 bioelectrical impedance body composition detector was used to test the body composition.Body mass index(BMI),skeletal muscle mass index(SMI),and PhA were collected.Some patients underwent measurement of grip strength.Muscle mass decline was diagnosed by using the SMI values recommended by the 2019 Asian Working Group for Sarcopenia(AWGS)(≤7.0 kg/m2 for males and≤5.7 kg/m2 for females).According to the measured SMI values,patients were divided into a group with normal muscle mass and a group with muscle mass decline.Univariate and multivariate Logistic analyses were employed to investigate the risk factors associated with muscle mass decline related to sarcopenia in the elderly.Additionally,the receiver operator characteristic(ROC)curve and the area under the curve were utilized to predict the significance of these factors in muscle mass decline.Results·A total of 359 chronic disease patients were enrolled,including 226 males and 133 females.There were 241 cases in the normal muscle mass group and 118 cases in the muscle mass decline group.The incidence of muscle mass decline related to sarcopenia in the elderly was 32.9%.The univariate Logistic regression analysis showed that age(OR=1.036,95%CI 1.013?1.060),comorbidities(OR=1.117,95%CI 1.025?1.217),aCCI(OR=1.123,95%CI 1.031?1.222),and high-density lipoprotein(OR=3.688,95%CI 2.065?6.622)were positively correlated with the risk of muscle mass decline in the elderly.BMI(OR=0.514,95%CI 0.443?0.597),PhA(OR=0.195,95%CI 0.126?0.303),hemoglobin(OR=0.984,95%CI 0.972?0.996)and triacylglycerol(OR=0.606,95%CI 0.424?0.866)were negatively correlated with the risk of muscle mass decline in the elderly.Multivariate Logistic regression model indicated that PhA(OR=0.338,95%CI 0.119?0.959)and BMI(OR=0.634,95%CI 0.476?0.844)were negatively correlated with the risk of muscle mass decline in elderly.The area under the ROC curve for predicting muscle mass decline related to sarcopenia in elderly by using BMI and PhA was 0.893(95%CI 0.855?0.931)and 0.786(95%CI 0.736?0.837),respectively.The sensitivity was 0.724 and 0.676,respectively.The specificity was 0.916 and 0.762,respectively.When BMI combined with PhA predicted muscle mass decline in the elderly,the area under the ROC curve was 0.917(95%CI 0.883?0.951).The sensitivity was 0.867,and the specificity was 0.860.Conclusion·aCCI is correlated with muscle mass decline associated with sarcopenia in the elderly.As BMI and PhA decrease,the risk of muscle mass decline in the elderly increases.The combination of BMI and PhA has a high predictive value in muscle mass decline in the elderly.No predictive value of chronic diseases comorbidities in muscle mass decline related to sarcopenia in the elderly is found.
摘要
Objective To assess the feasibility of employing chip resistors for retrospective dose reconstruction following nuclear accidents, to examine the effects of storage temperature and storage time on the optically stimulated luminescence (OSL) characteristics of the chip resistors, and to explore measures to mitigate these effects. Methods Chip resistors were analyzed using automated instruments for measuring thermoluminescence and OSL manufactured by Risø in Denmark with various parameters to understand the impact of storage temperature and storage time on OSL signals. Results The OSL signals of chip resistors exhibited exponential attenuation within 10 min after irradiation, and then stabilized (count change < 10%) within 2-7 days of storage. The chip resistors exhibited linear dose responses within 1-3 days of storage after 0.1-2 Gy irradiation. OSL signals diminished as the storage temperature increased. However, preheating at 130 ℃ for 1 min effectively eliminated the differences caused by temperatures between 25 ℃ and 45 ℃. Conclusion The OSL signals of chip resistors are influenced by storage temperature and storage time. When preheated at 130 ℃ for 1 min, chip resistors stored for 1-7 days and at 25-45 ℃ exhibited OSL signal errors of 10% or less. This result emphasizes the importance of preheating for measurements in practical applications, thus providing a scientific approach and a solid foundation for the use of chip resistors in retrospective dose reconstruction.
摘要
Objective@#To understand the prevalence and influencing factors of scoliosis among primary and middle school students in Shanghai, so as to provide reference for the prevention and control strategies of scoliosis in children and adolescents.@*Methods@#From September to December 2021, a total of 4 531 students from grade four of primary school to grade three of junior high school from 16 primary and middle schools in 4 districts of Shanghai were selected by multi stage stratified cluster sampling to carry out scoliosis screening and questionnaire survey. Independent sample t-test, Chi-squared test, Fisher s exact probability method and nonparametric Mann Whitney U-test were used for statistical analysis, and multivariate Logistic regression was used to analyze the influencing factors of scoliosis.@*Results@#The on the spot detection rate of scoliosis abnormality was 7.4% and the prevalence was 2.2%, mainly for thoracolumbar scoliosis (60.4%) and the scoliosis angle of 10° -<20°(88.1%). The results showed that the detection rate of scoliosis in boys was 1.6% and in girls was 3.3%, with a statistically significant difference ( χ 2=11.84, P < 0.01). There were significant differences in weight and BMI between scoliosis students and students with negative initial screening( t = -3.77, -5.30, P <0.01). And there was a statistically significant difference in the detection rate of scoliosis with different frequency of classroom seating arrangements ( Z =2.02, P <0.05). The results of multivariate Logistic regression showed that the risk of scoliosis in girls was higher than that in boys ( OR =1.87, 95% CI =1.21-2.88). BMI ( OR =0.89, 95% CI =0.83-0.95) and frequency of classroom seating arrangements ( OR =0.49, 95% CI =0.25-0.93) were correlated with lower rate of scoliosis. After stratification by sex, the frequency of classroom seating arrangements ( OR =0.26, 95% CI =0.10-0.67) in boys and the educational stage ( OR =2.35, 95% CI =1.26-4.41) in girls ( P <0.05) was correlated with higher rate of scoliosis, while BMI ( OR =0.86, 95% CI =0.79-0.94) in girls were correlated with lower rate of scoliosis.@*Conclusion@#Regular screening of scoliosis is an effective method for early detection of scoliosis. Girls in junior high school and low BMI should be paid close attention to. According to the occurrence and influencing factors of scoliosis, comprehensive prevention and control based on family, school, society, and other aspects can be carried out.
摘要
Objective@#To develop an approach for simultaneous detection of multi-mycotoxins in fresh fruits, so as to provide technical supports for mycotoxins surveillance in fresh fruits.@*Methods@#Fresh fruits were collected from markets and homogenized. Then, 2 g of fresh fruits were added with 10 mL of 0.1% formic acid ( 99∶1, v/v ) in acetonitrile and wortexed for 10 min. Following extraction with 1 g of sodium chloride and 4 g of anhydrous sodium sulfate, samples were centrifuged and 5 mL of the supernatant was cleaned up with 25 mg C18. Following centrifugation, the supernatant was dried under nitrogen. The residue was dissolved in 300 μL of methanol-acetonitrile mixture solution ( 1∶1, v/v ), and mixed evenly in 700 μL of the distilled water. Samples were then eluted in gradient series of 0.1% formic acid and 5 mmol ammonium formate and methanol-acetonitrile mixture solution ( 1∶1, v/v ). The 15 mycotoxins were determined using liquid chromatography-tandem mass spectrometry ( LC-MS/MS ) with electrospray ion source (ESI+/ESI-) under multiple reaction monitoring. In addition, a matrix-matched standard curve was employed for quantitative analysis.@*Results@#There was a good linear relationship for 15 mycotoxins at concentrations of 0.25 to 10 ng/mL ( R2>0.992 ), the LC-MS/MS method showed the detection limits of 0.1-1.0 μg/kg, the spiked recovery rates of 71.68%-117.50%, and the relative standard deviations ( RSDs ) of 0.01%-13.60%. The detection rate of mycotoxins was 27.09% in 203 fresh fruits sold in markets.@*Conclusions@#The optimized LC-MS/MS method can be used for simultaneous determination of multi-mycotoxins in fresh fruits.
摘要
OBJECTIVE@#To explore the genetic basis for a Chinese pedigree affected with genetic epilepsy with febrile seizures plus (GEFS+).@*METHODS@#Clinical data of the proband and his family members were collected. Following extraction of genomic DNA, the proband was subjected to high-throughput sequencing. Candidate variant was verified by Sanger sequencing of the proband and other family members.@*RESULTS@#The pedigree, including 6 patients with febrile seizures from 3 generations, was diagnosed with typical GEFS+. Among them, 2 had febrile seizures (FS), 1 had febrile seizures plus (FS+), and 3 had febrile seizures with focal seizures. High-throughput sequencing revealed that the proband has carried a heterozygous missense variant of c.4522T>A (p.Tyr1508Asn) of the SCN1A gene. Sanger sequencing confirmed that other five patients and one normal member from the pedigree have also carried the same variant, which yielded a penetrance of 85.7%.@*CONCLUSION@#The c.4522T>A (p.Tyr1508Asn) of the SCN1A gene probably underlay the disease in this pedigree. The pattern of inheritance was consistent with autosomal dominant inheritance with incomplete penetrance. Above finding has enriched the variant spectrum of the SCN1A gene.
Subject(s)
Humans , Epilepsy/genetics , /genetics , Pedigree , Phenotype , Seizures, Febrile/genetics摘要
Objective To investigate competence factors in new teachers of medical schools and construct the competence model. Methods The competence questionnaire for new teachers of medical schools was designed based on the literature review, semi-structured interviews and delphi method, and the questionnaire survey was conducted in new teachers of 12 medical schools . Factors were extracted by principal component analysis. Results Cronbach's α of questionnaire was 0.95. There were six factors in the model: scientific research ability (38.282％), teaching ability (10.118％), professional ethics (7.150％), communication skills (5.707％), personal characteristics (4.707％) and self-improvement ability (4.218％). Conclusion Construction of competence model in new teachers of medical schools can optimize teachers' pre-job training and provide references to study related policies.
摘要
Objective:To investigate the effect of Tongrnai Yangxin Pill on the serum hepcidin level of patients with Coronary Atherosclerotic Heart Disease and Anemia of Chronic Disease.Methods:Seventy patients with Coronary Atherosclerotic Heart Disease and Anemia of Chronic Disease whose age were above 40 years old were enrolled as the research group and divided into the medication group (group Ⅱ) (n=35) and the nonmedication group (group Ⅲ)(n=35),while 40 CAD patients were enrolled as the normal control group (group Ⅰ).Before and after medication,the Hepc,Hb,etc levels were compared between two groups.Results:Before medication,the levels of Hepc in the two research subgroup were significantly higher than that of the control group (P＜0.05).At 8 weeks after treatment,the Hepc level of group Ⅱ was significantly declined,and the level of Hb was increased than those before treatment (P ＜0.05);the Hepc levels of group Ⅰ and group Ⅲ showed no significant difference (P＞0.05),the Hepc levels of group Ⅱ and group Ⅲ were obviously higher than that of the control group (P ＜0.05),the Hepc levels of group Ⅲ was obviously higher than that of the group Ⅱ(P＜0.05),the Hb level of group Ⅲ was obviously lower than those of group Ⅰ and group Ⅱ (P＜0.05).Conclusion:Tongmai Yangxin Pill could reduce the level of Hepc and enhance the Hb levels of patients with Coronary Atherosclerotic Heart Disease and Anemia of Chronic Disease.It was useful to the patients with Coronary Atherosclerotic Heart Disease and Anemia of Chronic Disease,especially patients with mild anemia.
摘要
Objective To investigate the relationship between indoor radon concentration and air exchange rate for new residential building.Methods The indoor radon concentration and air exchange rate were measured in two new roughcast houses in Guangzhou and Hefei,respectively.The radon concentration was measured using radon instrument.The air exchange rate was measured by using tracer gas dilution method.Results The indoor radon concentrations measured in Guanzhou for two bedrooms in a 48-hour closed condition were 106 and 115 Bq/m3,the range of 17-181 and 6-224 Bq/m3.Air exchange rates were 0.16/h and 0.21/h.In Hefei,the twice measured values for one bedroom were 148 and 186 Bq/m3,the range of 8-224 and 14-290 Bq/m3,and air exchange rates were 0.14/h and 0.12/h.The indoor radon concentration exponentially decreased with the increase of air exchange rates.Conclusions Attention should be paid to the indoor radon pollution issue that may arise in new residential buildings of energy-saving design due to low air exchange rate.
摘要
Objective To evaluate the relevance of PET CO 2 ,TcPCO 2 and PaCO 2 in pediatric patients with congenital heart disease.Methods Eighty pediatric patients with congenital heart disease were scheduled for elective cardiac operation with cardiopulmonary bypass,aged 1 month to 5 years, 42 male and 38 female,were divided into 4 groups:group N1,cyanotic type congenital heart disease with severe pulmonary hypertension;group N2,cyanotic type congenital heart disease without pul-monary hypertension;group N3,non-cyanotic congenital heart disease with severe pulmonary hyper-tension;group N4,non-cyanotic congenital heart disease with mild pulmonary hypertension or normal of pulmonary artery pressure,20 cases in each group.The same anesthesia methods were selected in each group.PET CO 2 ,TcPCO 2 and PaCO 2 before operation were recorded,and the relevance among them was analyzed.Results In groups N1,N2 and N3,the differences of PET CO 2 and PaCO 2 were significant,,while the difference was relatively small in group N4;the difference of TcPCO 2 and PaCO 2 were relatively small between the four groups.In Groups N1,N2 and N3,the values of TcP-CO 2-PaCO 2 value were significantly less than that of PET CO 2-PaCO 2 ;in group N4,TcPCO 2-PaCO 2 value was obviously higher than that of PET CO 2-PaCO 2 values (P 0.05,0.02
摘要
Objective To explore the prognostic value of N-terminal pro-brain natriuretic peptide ( NT-pro-BNP) levels in critically ill infants. Methods Eighty-one critically ill infants were enrolled from January 2013 to January 2014 in pediatric intensive care unit. The minimum of pediatric critical illness score ( PCIS) and the number of dysfunction organs were calculated within 24 hour after admission. According to PCIS,the critically ill infants were divided into extremely critical group(PCIS≤70,n=25),critical group (PCIS 71-80,n=30)and non-critical group(PCIS>80,n=26). According to the prognosis,the critically ill infants were divided into survival group (n=68)and death group(n=13). The serum NT-pro-BNP levels were determined on the first day,third day and convalescent phase. The relationships of serum NT-pro-BNP levels with PCIS and the number of dysfunction organs and prognosis were observed. Results The study showed statistical significances of serum NT-pro-BNP levels among the extremely critical group, critical group and non-critical group,whether on the first day,or on the third day and convalescent phase(P<0. 01). There were statistical significances of serum NT-pro-BNP levels among different stages of the disease in each group(P<0. 01). Compared with survival group,PCIS was significantly lower and the serum NT-pro-BNP levels and the number of dysfunction organs were significantly higher in death group. The serum NT-pro-BNP level on the third day was higher than that on the first day in death group ( P<0. 01 ) , while no significant difference was found in survival group. The serum NT-pro-BNP levels on the first day and the third day and PCIS were negatively correlated(r= -0. 59,P<0. 01;r= -0. 66,P<0. 01). The serum NT-pro-BNP levels on the first day and the third day and the number of dysfunction organs were positively correlated(r=0. 40,P<0. 05;r=0. 57,P<0. 01). Conclusion The serum NT-pro-BNP levels of the critically ill infants are correlated with disease severity,and can be useful for assessing the severity of critical illness.
摘要
<p><b>OBJECTIVE</b>The aim of this study was to explore the expression of basic fibroblast growth factor (bFGF) and fibronectin during the healing process of allograft tissue engineering skin.</p><p><b>METHODS</b>The tissue engineering skin that was obtained from neonatal SD rats was cultured in the lab. Afterwards, the skin was grafted into adult SD rats, and the expressions of bFGF and fibronectin were detected on the 7th, 10th, 14th, 20th and 30th day after the allograft of the tissue engineering skin. The autografted skin in 15 adult Wistar rats and the normal skin in 15 Wistar were treated as the control. HE staining and immunohistochemical staining were used to examine the healing of grafted skin.</p><p><b>RESULTS</b>The expression of bFGF and fibronectin was the strongest on the 10th day after graft, and was weaker before the 10th day and after the 14th day. The expression changes of bFGF and fibronectin were similar as they were in the autograft group.</p><p><b>CONCLUSION</b>The expression changes of bFGF and fibronectin in the tissue engineering skin during the process of wound healing were similar to those of autografted skin, and these can promote the repair of tissue engineering skin allograft.</p>
Subject(s)
Animals , Rats , Animals, Newborn , Cells, Cultured , Culture Techniques , Fibroblast Growth Factor 2 , Genetics , Fibronectins , Genetics , Rats, Sprague-Dawley , Skin , Cell Biology , Metabolism , Skin Transplantation , Tissue Engineering , Transplantation, Homologous摘要
Objective To study the histocompatibility of tissue engineered skin with the observation of the effects of selectins E and P on the immunological rejection after skin allograft in rats. Methods Tissue engineered skin was prepared as follows: The materials obtained from the neonatal SD rats were cultured and then grafted onto the adult Wistar rats. The expression of selectins E and P in the grafted skin was determined with immunohistochemical staining. Results The expression of selectins E and P was significantly higher in the rats with allograft than in the rats with the grafts of tissue-engineered material. Conclusion Selectins E and P play an important role in the immunological rejection after allograft of skin but the tissue-engineered skin graft possesses favorable histocompatibility and shows no obvious immunological rejection.
摘要
<p><b>OBJECTIVE</b>To elucidate the histocompatibility of tissue engineered rat skin through studying the effect of TNF-alpha and IL-2 in immunological rejection after rat skin allograft.</p><p><b>METHODS</b>Tissue engineered skin that the basic materials were taken from neonatal SD rats was cultured in lab, grafted to adult Wistar rats. The expressions of TNF-alpha and IL-2 in grafted tissue were detected with immunohistochemical staining and Western blot.</p><p><b>RESULTS</b>The expressions of TNF-alpha and IL-2 were remarkable in skin allograft group, but low in tissue engineered skin group.</p><p><b>CONCLUSION</b>The expressions of TNF-alpha and IL-2 and the immunological rejection were closely related after skin allograft, but the tissue engineered skin has favorable histocompatibility and doesn't arose obvious immunological rejections.</p>