ObjectiveTo learn the inner experience of decisions to seek medical attention among patients with ischemic stroke and to explore the factors that affect patients’ early decisions to seek medical attention， providing a basis for formulating intervention measures to reduce patient delays. MethodsUsing qualitative research methods， semi-structured in-depth interviews were conducted with 24 patients with ischemic stroke who had delayed seeking medical attention through purposive sampling， and the data were analyzed by category analysis method. ResultsThe five major themes that affected ischemic stroke patients’ decisions to seek medical attention were symptom experience （insufficient attention to disease and the impact of symptoms on the patients）， symptom assessment （symptom perception， symptom interpretation， and symptom recognition）， symptom response （psychological denial and self-relief）， prior knowledge of the diseases （deficient knowledge and stroke experience）， as well as environmental-social factors （morbidity context， external information support， and medical insurance）. ConclusionUnder the guidance of cognitive， psychosocial， and environmental frameworks， targeted intervention strategies should be proposed to reduce the incidence of delayed decisions to seek medical attention among patients with ischemic stroke.

Objective To observe the value of Zero-Shot Noise2Noise(ZS-N2N)based on Z-axis correlation for reducing noise of low dose CT(LDCT)images.Methods CT data of the cancer imaging archive were enrolled,including normal dose CT(NDCT)images and LDCT images,with 3 sets of chest and 3 sets of abdominal images.Noise on LDCT images were reduced with ZS-N2N method based on Z-axis correlation,and the peak signal-to-noise ratio(PSNR),structural similarity(SSIM)and time-consuming of reducing noise were compared with those of Self2Self,simple ZS-N2N and traditional Block-matching and 3D filtering(BM3D).Results After reducing noise,noise on Self2Self denoised images remained significant,the structure edges on BM3D denoised images were blurry with some details lost,while simple ZS-N2N and ZS-N2N based on Z-axis correlation denoised images preserved more details and had better quality.PSNR and SSIM of Self2Self denoised images were poor and the time-consuming were longer.PSNR,SSIM and time-consuming of the other 3 methods were similar,among which PSNR of ZS-N2N based on Z-axis correlation were slightly higher than BM3D and simple ZS-N2N,but the time-consuming were also slightly longer.Conclusion ZS-N2N based on Z-axis correlation had high value for reducing noise of LDCT images.

It is an urgent need for the development of medical and health undertakings in the new era to build a high-quality university education system and cultivate high-quality personnel for laboratory medicine. In the process of building a national first-class specialty, the medical laboratory technology specialty of Southern Medical University adheres to the concept of high-quality university education and improves the training level of laboratory medicine personnel through the teaching reform practice of constructing the whole-process moral education system, systematical training mode, internationalized teaching team, and intelligent teaching technology. In this paper, we analyzed the connotation and construction experience of a high-quality university education system of laboratory medicine, in order to increase the exchange and communication between different colleges and universities, and make contributions to the national strategic goal of building a powerful country in education before 2035.

Objective To investigate the relationship between serum three triacylglycerol lipase (ATGL) and inflammatory factors in patients with coronary atherosclerotic heart disease (CHD).Methods 135 cases of CHD patients,and 50 healthy people were enrolled in the study.CHD patients were divided into stable angina pectoris (SAP) group (53 cases),unstable angina pectoris (UAP) group(46 cases) and acute myocardial infarction (AMI) group (36 cases) according to relevant diagnostic criteria.The serum levels of ATGL,tumor necrosis factor (TNF-α),interleukin-6(IL-6), interleukin-10(IL-10),1,25 dihydroxy vitamin D3[1,25(OH)2D3] were measured by ELISA, and statistical treatment was performed.Results The levels of ATGL,1,25(OH)2D3 in CHD group were lower than that in control group,and the levels of TNF-α,IL-6 and IL-10 were higher than those of control group(P<0.05).Comparison among different clinical types of CHD patients showed that ATGL,1,25 (OH)2D3 levels of AMI group were significantly lower than those of SAP group and UAP group,while TNF-α,IL-6 and IL-10 were higher than those of SAP group and UAP group(P<0.05);the levels of ATGL,1,25(OH)2D3 in UAP group were lower than those in SAP group,and TNF-α and IL-10 were higher than those in SAP group(P<0.05).Spearman correlation analysis showed that in the CHD group the serum levels of ATGL negatively correlated with TG,LDL-C,LP (a),TNF-α,IL-6,IL-10(r=-0.289,-0.227,-0.359,-0.243,-0.205,-0.337,P<0.05),while positively correlated with age,HDL-C,1,25(OH)2D3(r=0.267,0.356,0.229,P<0.05).Conclusion The ATGL levels in patients with CHD decreases with the increase of inflammatory factors,and plays a certain anti-inflammatory role in the progression of CHD.It can be used as a monitoring indicator to reflex the progress of CHD.

Objective To establish a method of quantiying trace α-galactosidase from Bacteroides fragilis in enzymatic conversion of blood group B to O red blood cells ( B-ECO RBCs) .Methods BALB/c mice were immunized with purified recombinant B.fragilisα-galactosidase ( the purity>90%) to prepare monoclonal antibodies.The ascites were prepared using hybridoma cell lines stably secreting antibody and purified by HiTrap rProtein A column.The antibody titer and spe-cificity were detected by ELISA and Western blotting, respectively.Purified monoclonal antibody and rabbit polyclonal an-tibody were applied to detect residual enzyme in B-ECO RBCs and the washing solution was analyzed by indirect ELISA. Results A high titer and purity antibody was obtained.Western blotting showed that the antibody specifically reacted with B.fragilisα-galactosidase.Moreover, indirect ELISA was sensitive enough to detect the minimal amount of residualα-gal-actosidase at the concentration of 1 ng/ml.After four repeat washing cycles with 1∶4 ( v/v) phosphate-buffered saline, the amount of residual enzyme in B-ECO RBCs was less than 10 ng/ml.Conclusion An effective method of detecting the min-imal amount of residual α-galactosidase in blood conversion is established for safety evaluation of universal RBCs prepara-tion by enzymatic treatment.

Objective To reduce immunogenicity of porcine skin by removingα-Gal epitopes expressed in cell surface and extracellular matrix using recombinant α-galactosidase produced by Bacteroides fragilis.Methods The porcine skin was harvested from healthy 2-month-old pigs without any skin disorders before being sterilized by iodine and 75%alcohol, respectively.Enzymatic removal of α-Gal antigen was followed by washing with PBS.The α-Gal antigen in the prepared porcine skin was measured with immunofluorostaining of cryosections and the residual enzyme was measured with a double-antibody sandwich ELISA method.Enzymatic removal procedures were optimized by detecting residual enzyme and the effi-cacy ofα-Gal removal under different enzymatic and washing conditions.Results Efficient enzymatic and washing methods were established to removeα-Gal antigen.Theα-Gal removal efficacy was above 90% and residual enzyme was undetect-able (αprescribed minimum ofα-galactosidase detection with indirect ELISA was 1 ng/ml) .Conclusion It is feasible to efficiently removeα-Gal antigen under these enzymatic and washing conditions, and a method of producing low-immunoge-nicity pig skin dressing for burn is established.

Objective To evaluate the effects of isoflurane anesthesia on inflammatory responses and long-term cognitive function in the hippocampi of neonatal rats .Methods Forty-six Sprague-Dawley rats of both sexes , aged 7 days ,weighing 12-17 g ,were randomly divided into 2 groups (n=23 each):control group (group C) and isoflurane anesthesia group (group I ) .In group I ,the rats were exposed to 2.5% isoflurane for 3 min to induce anesthesia and then exposed to 1.5% isoflurane for 4 h to maintain anesthesia ,while in group C the rats were only exposed to air for 4 h .Eight rats in each group were sacrificed and hippocampi were removed for determination of the levels of interleukin-6 ,interleukin-1βand tumor necrosis factor-α.Open field and Morris water maze tests were carried out three weeks later in the left rats .Results Compared with group C ,the escape latency was significantly prolonged ,the time of staying at the central region was shortened ,the time of staying at the border region was prolonged ,the total distance was reduced , and the contents of interleukin-1β and tumor necrosis factor-αwere increased in group I ( P<0.05) .Conclusion Isoflurane anesthesia results in decreased cognitive function ,which may be related to promotion of inflammatory responses in the hippocampi of neonatal rats .

Objective To summarize the outcome of nasopharyngeal carcinoma ( NPC) treated by helical tomotherapy in the Chinese PLA general hospital. Methods Between September 2007 and August 2010, 121 newly diagnosed NPC patients were treated by radiotherapy with Tomotherapy system, with ( n =90) or without ( n = 31) concurrent chemotherapy or molecular target therapy. The prescription dose was 70 - 74 Gy/33f to primary tumor and positive lymph node planning target volume,60. 0 - 62. 7 Gy/33f to high risk planning target volume, and 52 -56 Gy/33f to low risk planning target volume. Acute side-effects were evaluated with RTOG/EORTC criteria. Results The remission rate of primary lesion and positive lymph nodes was 95. 0％ and 99. 0％ , respectively. The follow-up rate was 100％ . The number of patients with 1 ,2 and 3 years followed-up were 99 , 49 , and 7. The 1-, 2-and 3-year local relapse-free survival rates were 97. 30％ , 97. 3％ and 97. 3％ , respectively. The 1-,2-and 3-year nodal relapse-free survival rates were 100％ , 100％ and lOO％, respectively. The 1-, 2-and 3-year distant metastasis-free survival rates were 98. 4％ , 96. 3％ and 96. 3％ , respectively. The 1-, 2-and 3-year overall survival rates were 96. 5％ ,92. 6％ and 86. 8％ , respectively. Acute toxicities of skin, oral mucosa and xerostomia with grade 0,1,2 and 3 were 5. 0％ , 74. 4％ , 15. 7％ and 4. 9％ ; 0. 8％ , 37. 2％ , 57. 9％ and 4. 1％ ; 3. 3％ , 53. 7％ ,43. 0％ and 0％ , respectively. Xerostomia restored with time, no grade 2 or more xerostomia was observed 1 year after radiation therapy. Concurrent chemotherapy significantly increased incidence of mucositis,esophagitis and tracheitis. Conclusion Helical tomotherapy is efficient, secure and effective modality for the treatment of nasopharyngeal carcinoma.

Objective To observe the pain behavioral performance of rats that different sensory nerve fibers were transected,and examine the expression of brain-derived neurotrophic factor(BDNF) in these models.Methods Twenty-four rats were divided into three groups according to random number table method:SUR group,GS group and SHAM group, which received sural nerve transection, gastrocnemius-soleus nerve transection or sham operation respectively.There were 8 rats in every group.The expression of BDNF in the lumbar 5 DRG and spinal dorsal horn were detected,and the types of damaged cells were also observed.Results In GS group, 50% paw-withdrawal thresholds were significantly decreased on the ipsilateral hind paw compared with baseline and with those in SHAM group,and the paw-withdrawal durations in response to the thermal stimulus increased significantly (P＜0.01 ＝.In contrast, no change was found in SUR group(P＞0.05 ).The expression of BDNF in the lumbar 5 DRG ( (37.87 ± 4.23 ) % ) and spinal dorsal horn ( (21.9 ± 3.1 ) % ) was significantly higher in GS group than in SHAM group( ( 17.31 ± 2.12 ) %, ( 12.6 ± 1.3 ) % ), and no significant difference was found between SUR and SHAM groups(P＞0.05 ).FG opposite cells which also expressed BDNF in GS group were more than those in SUR group ( (47.7 ± 1.8) % and (26.7 ± 2.3 ) % ) (P ＜ 0.01 ＝.The percentage in N200 and FG double positive cells to N200 positive cells in GS group was significantly increased in GS group than those in SUR group ( (47.7 ±1.8 ) %, (26.7 ± 2.3 ) % ) (P ＜ 0.01 ＝.Conclusion The data suggest that injury of the sensory nerve innervating skin does not produce hyperalgesia, but injury of the sensory nerve innervating muscle does.Different kinds of neuron were damaged and the differences of BDNF expression is essential for this difference.

Objective To find a biomechanical evaluation methods of manual performance fatigue,for providing the feasible methods for the hand fatigue of spacesuit glove.Method Twelve females and forteen males in two groups served as the subjects and participated in the experiments of changeless force fatigue,including gripping,pinching and screwing,and took part in the nondimensional force fatigue.Result Manual performance fatigue could be fully evaluated based on gripping,pinching and screwing.The nondimensional force fatigue had widely applied ranges and well veracity.The combination of nondimensional subjective and objective evaluations was the optimal fatigue evaluation method.Conclusion The results can provide the feasible methods for performance evaluation of spacesuit glove system.