Objective To investigate the combined biological effects of low dose radiation,carbon monoxide,benzene and noise on rats.Methods Sixteen male SD rats were randomly divided into experiment group and control group.The experiment group was exposed to carbon monoxide,benzene,low dose radiation and noise daily,the control group was in common environment.Peripheral blood,organ index,and marrow DNA content were detected.Two-dimensional electrophoresis (2-DE) was performed on serum protein analysis.Differential expressed proteins were identified by a matrix assisted laser desorption/ionization time of flight mass spectrometry (MAIDI-TOF-MS).Results Compared to control group,the liver index,spleen index,thymus index,leukocytes,platelets count,and marrow DNA content of the experiment group were decreased significantly (t =2.732,4.141,3.053,2.211,2.668,11.592,P ＜0.05).12 altered proteins were detected and through identification,3 proteins were definite in terms of serum amyloid A-4 protein (SAA4),trichoplein keratin filament-binding protein (TCHP) and tubulin alpha-4A chain (TUBA4A).Conclusions The hematopoietic system and immune system of rats are damaged significantly with the changes of several serum protein expressions by the combined exposure of low dose radiation,carbon monoxide,benzene and noise.This study may provide new information for the mechanism of the combination effects.

Objective:To prepare old tea buccal tablets using wet granulation method and optimize the preparation technology. Methods:The amount of each adjuvant was studied by single factor experiments, and the formula of the buccal tablets was optimized by the orthogonal experiments using taste and disintegration time as indices. Results:The optimal formula was composed of old tea ex-tract 30 g,mannitol 60g,PEG6000 20 g,aspartame 10 g,citric acid 10 g and menthol crystal 1 g. All the tested indices including ap-pearance, hardness and disintegration time met the requirements described in Chinese pharmacopeia. Conclusion: The preparation technology is reasonable and feasible for the industrial production.

Objective To investigate the radioprotective effect of cimetidine on survival rate and hematopoietic system in acutely irradiated mice.Methods The total body irradiation doses were 6.0Gy and 8.0Gy respectively at 1.01Gy/min rate. Sixty healthy male C57BL/6 mice were randomly divided into control group, model group, positive-drug (523) group and cimetidine groups (33.3mg/kg, 100mg/kg and 300mg/kg). Each group had ten mice. The mice were given intragastric administration of cimetidine for 6d before the irradiation in cimetidine groups, and 523 was administered before irradiation once a day for one day in 523 group, and at 5h after irradiation, was given again. The 30d survival rate after 8.0Gy irradiation was recorded. The peripheral blood cells, bone marrow DNA content and frequency of micronucleated polychromatic erythrocytes (fMNPCE) were determined 30d after 6.0Gy irradiation.Results After 8.0Gy irradiation, all the mice died on 21th day in model control group. The survival rates in cimetidine groups were 50%, 20% and 30%, respectively. After 6.0Gy irradiation on 30th day, compared with control group, the peripheral white blood cells (WBC) and bone marrow DNA content were decreased significantly (P<0.01,P<0.05) in model group, and fMNPCE was increased significantly (P<0.05). Compared with model group, WBC was significantly increased in 300mg/kg cimetidine group (P<0.01). In cimetidine groups, the bone marrow DNA content was increased significantly after irradiation (P<0.01 orP<0.05), and the fMNPCE was decreased significantly (P<0.01 orP<0.05) and tended towards normal.Conclusion Cimetidine could improve 30d survival rate of acutely irradiated mice and has good protective effect on hematopoietic system.

Nursing skill competitions are the wind vane for clinical nursing development, and the teaching concepts, proposition forms, and evaluation systems demonstrated by competitions have a strong reference value for nursing teaching. This article introduces the knowledge selection and integration from nursing-related courses according to the problems and objectives to be solved by drawing on the STEM education concept in comprehensive nursing practical training in the context of integration of competition and education. Realistic problem scenarios can be created with clinical cases as the carrier or main line, and then the Tanner clinical judgment model is used to guide students to conduct a comprehensive analysis of cases, thereby helping students to develop clinical thinking ability and comprehensive practical skills, so as to bridge the gap between the contents learned at school and nursing work in clinical practice and help nursing students adapt to clinical practice as soon as possible.

Objective To observe the characteristics of brain activation of multiple sclerosis (MS) patients and healthy controls at functional magnetic resonance imaging (fMRI) with olfactory stimulation,determine the locations of activation in areas of olfactory center and explore the MS olfactory related network.Methods Eighteen MS patients from the Affiliated Hospital of North Sichuan Medical College from February 2017 to March 2018 were enrolled as MS group,and 20 matched healthy adults during the same period served as controls.The Visual Analogue Scale was used to evaluate olfactory function in all subjects,the rest structure MRI was performed first,and volatile gases of lavender and rose solution were used to alternately stimulate olfactory during fMRI scanning.The brain activation was obtained by using matlab2013a and SPM8 softwares.The distribution and quantity of demyelination lesions were counted on T2 weighted image,and Spearman correlation analysis was done with SPSS 17.0 software package.Results The activated brain areas in the healthy control group included bilateral middle frontal gyrus,bilateral insula,bilateral supramarginal gyrus,bilateral orbitofrontal gyrus,right thalamus,right central anterior gyrus,bilateral cingulated gyrus,bilateral hippocampus,bilateral amygdala and bilateral superior frontal gyrus (t =2.11,P＜0.05).The activated brain areas in the MS group included right cerebellum,left insula,left superior temporal gyrus,right inferior frontal gyrus (t=2.19,P＜0.05).Compared with the control group,the MS group showed statistically significant decrease in activated values in right insula,right amygdala,right inferior frontal gyrus,right frontal middle gyrus,and the left supramarginal gyrus (t=2.04,P＜0.05).The distribution and number of demyelination lesions and major activation of brain regions with olfactory in the MS group demonstrated no significant correlation (r=-0.524,P=0.054).Conclusions Multiple brain areas involved in the olfactory processing and olfactory-related brain network existed.The activation of olfactory center had dominance in the right brain.The activation of the brain area in the MS group was significantly reduced,and the activation voxel and activation intensity were weakened.The olfactory-related brain network changed in MS patients.The distribution and number of demyelination lesions had no significant effect on the major activation of brain regions with olfactory stimulation.

Objective:To compare the efficacy of articaine infiltration anesthesia and lidocaine nerve block anesthesia in pulpotomy of deciduous mandibular second molars.Methods:Single blind crossover test was used for the pediatric patients who required bilateral de-ciduous mandibular second molar pulpotomy were given articaine infiltration anesthesia and lidocaine nerve block anesthesia respectively before the 2 times of operation.After the injection of anesthetic drugs and dental pulp treatment,the patients'responses to pain were e-valuated through sound,eye and body movements,and Wong-Baker facial pain rating scales.Quantitative comparisons were made.Student's t-test and chi-square test were performed for the collected data.Results:50 pediatric patients who met the inclusion criteria and successfully completed 2 treatments without any missed visits or adverse events.During the process of articaine infiltration anesthe-sia,the scores of the 3 indicators of pain severity,namely sound,eye and body movements,were lower than those of lidocaine nerve block anesthesia(P＜0.05).The analysis of facial pain rating scales also suggested that patients'pain and discomfort during the infiltra-tion anesthesia process with articaine were milder(P＜0.05).During the treatment of pulpotomy,both pain assessment methods showed no statistically significant difference in pain perception between the 2 anesthesia injections(P＞0.05).Conclusion:Articaine infiltra-tion anesthesia may effectively replace lidocaine nerve block anesthesia in pulp treatment of mandibular primary molars.

OBJECTIVE： To study the effects of cimetidine on low dose rate irradiation-induced liver cell apoptosis in Beagle dogs. METHODS： Healthy male Beagle dogs were randomly divided into normal control group， model control group， positive drug group （lentinan， 21.33 mg/kg） and cimetidine low-dose， medium-dose and high-dose groups （5.33， 10.67， 21.33 mg/kg）， with 4 Beagle dogs each. Except for normal control group， other groups were given 60Co-γ accumulative irradiation （dosage rate： 0.040 8 mGy/min） for 23 d； the medication groups were given relevant medicine orally before irradiation， once a day. Twenty-four hours after stopping irradiation， TUNEL method was used to detect the apoptosis of liver cells in Beagle dogs. The percentage of apoptotic cells was calculated. The expression level of apoptosis-related proteins （Bax， Bcl-2， Caspase-3， p53） in liver tissue was detected by immunohistochemistry. RESULTS： Compared with normal control group， apoptotic cells and Bax， Caspase-3， p53 positive cells were increased significantly in liver tissue of Beagle dogs in model control group； the percentage of apoptotic cells， protein expression levels of Bax， Caspase-3 and p53 were increased significantly； Bcl-2 positive cells were decreased significantly， and its protein expression level was decreased significantly （P＜0.05 or P＜0.01）. Compared with model control group， above positive cells of liver tissue in Beagle dogs were changed to different extents in medication groups； the percentage of apoptotic cells and protein expression levels of p53 in medication groups， protein expression levels of Bax in positive drug group， cimetidine low-dose and high-dose groups as well as protein expression levels of Caspase-3 in cimetidine groups were decreased significantly； protein expression levels of Bcl-2 were increased significantly in cimetidine groups. The percentage of apoptotic cells in cimetidine medium-dose and high-dose groups as well as protein expression levels of Caspase-3 in cimetidine groups were all lower than positive control group. Protein expression level of p53 in cimetidine low-dose group was significantly higher than positive drug group （P＜0.05 or P＜0.01）. CONCLUSIONS： Cimetidine can inhibit the low dose rate irradiation-induced apoptosis of liver cells in Beagle dogs， and certainly protect liver cells against irradiation. The mechanism of it may be associated with up-regulating the protein expression of Bcl-2 and down-regulating the protein expression of Bax， Caspase-3 and p53 in liver cells.