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Objective:To evaluate artificial intelligence constructed by deep convolutional neural network (DCNN) for the site identification in upper gastrointestinal endoscopy.Methods:A total of 21 310 images of esophagogastroduodenoscopy from the Cancer Hospital of Chinese Academy of Medical Sciences from January 2019 to June 2021 were collected. A total of 19 191 images of them were used to construct site identification model, and the remaining 2 119 images were used for verification. The performance differences of two models constructed by DCCN in the identification of 30 sites of the upper digestive tract were compared. One model was the traditional ResNetV2 model constructed by Inception-ResNetV2 (ResNetV2), the other was a hybrid neural network RESENet model constructed by Inception-ResNetV2 and Squeeze-Excitation Networks (RESENet). The main indices were the accuracy, the sensitivity, the specificity, positive predictive value (PPV) and negative predictive value (NPV).Results:The accuracy, the sensitivity, the specificity, PPV and NPV of ResNetV2 model in the identification of 30 sites of the upper digestive tract were 94.62%-99.10%, 30.61%-100.00%, 96.07%-99.56%, 42.26%-86.44% and 97.13%-99.75%, respectively. The corresponding values of RESENet model were 98.08%-99.95%, 92.86%-100.00%, 98.51%-100.00%, 74.51%-100.00% and 98.85%-100.00%, respectively. The mean accuracy, mean sensitivity, mean specificity, mean PPV and mean NPV of ResNetV2 model were 97.60%, 75.58%, 98.75%, 63.44% and 98.76%, respectively. The corresponding values of RESENet model were 99.34% ( P<0.001), 99.57% ( P<0.001), 99.66% ( P<0.001), 90.20% ( P<0.001) and 99.66% ( P<0.001). Conclusion:Compared with the traditional ResNetV2 model, the artificial intelligence-assisted site identification model constructed by RESENNet, a hybrid neural network, shows significantly improved performance. This model can be used to monitor the integrity of the esophagogastroduodenoscopic procedures and is expected to become an important assistant for standardizing and improving quality of the procedures, as well as an significant tool for quality control of esophagogastroduodenoscopy.
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Purpose To investigate the expression of SMOC2 in papillary thyroid carcinomas(PTC)and its efficacy in joint diagnosis with CK19,Galectin-3,MC and BRAF V600E.Methods Bioinformatics was uesd to analyze the mR-NA expression differences of SMOC2 in PTC and benign thyroid tissues in the Gene Expression Omnibus database and The Canc-er Genome Atlas database.Detection of SMOC2 protein expres-sion in paraffin tissue of 75 cases of PTC and 45 cases of papilla-ry thyroid hyperplasia(PTH)was used by using EnVision meth-od,combined with CK19,Galectin-3,and MC and BRAF V600E for sensitivity and specificity analysis.Results The bioinformatics analysis results showed that the mRNA expression level of SMOC2 in PTC tissue was significantly lower than that in benign thyroid tissue(P<0.05),and the area under the curve(AUC)predicted by SMOC2 for PTC diagnosis was 0.910(P<0.001).The immunohistochemical results showed that the ex-pression of SMOC2 in PTC was significantly lower than that in PTH tissue(P<0.001),and the AUC of SMOC2 for PTC diag-nosis was 0.898(P<0.001).The AUC of SMOC2 combined with CK19,Galectin-3,MC and BRAF V600E in the diagnosis of PTC was 1.000(P<0.001),and the AUC values of the combination of other markers were lower than 1.000.Conclu-sion The expression of SMOC2 in PTC is significantly de-creased,which can be used as an important marker for the diag-nosis and differential diagnosis of PTC.Combined with CK19,Galectin-3,MC and BRAF V600E,the sensitivity and specifici-ty of PTC can be improved to a certain extent.
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Cerebral small vessel disease (CSVD) is a common cerebrovascular disease in clinical practice. Its onset is hidden and its clinical manifestations are diverse. Studies have shown that there are pleiotropic effects and recurrent activation phenomenon between the functional imbalance of neurovascular unit (NVU) and a series of pathophysiological processes, such as vascular endothelial dysfunction, blood-brain barrier permeability change and glial cell activation, which jointly promote the progress of CSVD under the action of inflammatory and immune factors. This article reviews the role of NVU in the occurrence and development of CSVD.
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Objective:To explore the application value of problem-based learning (PBL) based on production-oriented approach (POA) theory in clinical practice teaching in department of hand and foot surgery.Methods:A total of 112 interns from the Department of Hand and Foot Surgery in Affiliated Hospital of Jining Medical University from January 2019 to October 2020 were randomly divided into control group and observation group, with 56 interns in each group. The control group was taught by PBL teaching, and the observation group was taught by PBL teaching based on POA theory. The two groups of interns were compared in terms of the evaluation of teaching effect, the statistics of errors in practice assessment, the assessment scale of independent learning ability, the career maturity inventory attitude scale, and the satisfaction of interns with their teachers. SPSS 25.0 was used for Chi-test and t-test. Results:The teaching effect and the satisfaction of interns with the teacher in the observation group were better than those of the control group ( P<0.05); the error rate of unskilled physical examination and the error rate of poor aseptic debridement concept in the observation group were all lower ( P<0.05); there was no significant difference in the error rate of irregular writing of medical records, the error rate of lack of medical history collection, and the error rate of communication errors between the two groups ( P>0.05). After teaching, the scores of independent learning ability and career maturity inventory attitude scale in the observation group were higher than those in the control group ( P<0.05). Conclusion:The PBL teaching based on POA theory has a good effect in the clinical practice teaching in the department of hand and foot surgery, and it is worthy of further promotion.
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Objective To observe the changes of interleukin-18 (IL-18),interleukin-33 (IL-33) and fractional exhaled nitric oxide (FeNO) in children with acute respiratory syncytial virus (RSV) bronchiolitis,and explore the potential mechanism of the transformation from acute RSV bronchiolitis to recurrent wheezing.Methods Fifty-three children with RSV bronchiolitis (RSV bronchiolitis group),32 children with repeated wheeze (repeated wheeze group) and 30 children receiving regular physical examination (healthy control group) from January 2016 to January 2017 in Cangzhou People's Hospital of Hebei Province were selected.The serum IL-18 and IL-33 at the time of inclusion and 2,3 months after inclusion were detected by enzyme linked immunosorbent assay,the FeNO at the same time was detected by multiple breathing technique,and the indexes were compared.The correlation between FeNO and IL-33,IL-18 was analyzed by Spearman method.Results The IL-18 at the time of inclusion and 2,3 months after inclusion in RSV bronchiolitis group and repeated asthmatic group were significantly higher than those in healthy control group:(10.89 ± 1.54) and (14.86 ± 5.54) ng/L vs.(7.26 ± 3.25) ng/L,(13.74 ± 4.16) and (15.45 ± 5.75) ng/L vs.(7.28 ± 3.56) ng/L,(11.38 ± 6.21) and (14.86 ± 5.28) ng/L vs.(7.18 ± 3.41) ng/L,those in repeated asthmatic group were significantly higher than those in RSV bronchiolitis group,and there were statistical differences (P<0.05).The IL-33 levels at the time of inclusion and 2,3 months after inclusion in RSV bronchiolitis group and repeated asthmatic group were significantly higher than those in healthy control group:(17.68 ± 5.25) and (13.14 ± 5.01) ng/L vs.(3.69 ± 1.61) ng/L,(15.68 ± 4.16) and (15.11 ± 5.24) ng/L vs.(3.28 ± 1.56) ng/L,(13.87 ± 6.21) and (14.11 ± 5.14) ng/L vs.(3.18 ± 1.41) ng/L,IL-33 levels at the time of inclusion in RSV bronchiolitis group were significantly higher than those in repeated asthmatic group,and there were statistical differences (P<0.05).The FeNO levels at the time of inclusion and 2,3 months after inclusion in repeated asthmatic group were significantly higher than those in RSV bronchiolitis group and healthy control group:(13.14 ± 4.47) ppb vs.(1.89 ± 1.54) and (7.26 ± 4.25) ppb,(14.75 ± 5.15) ppb vs.(7.74 ± 4.16) and (7.28 ± 4.12) ppb,(13.68 ± 5.62) ppb vs.(11.38 ± 6.21) and (7.18 ± 3.41) ppb;compared with that in healthy control group,FeNO at the time of inclusion in RSV bronchiolitis group was significantly decreased,and at 3 months was significantly increased,and there were statistical differences (P<0.05).Correlation analysis result showed that FeNO at 2 and 3 months after inclusion in RSV bronchiolitis group had positive correlation with IL-18 level at the time of inclusion and 2,3 months after inclusion (P<0.05),and negative correlation with IL-33 (P<0.05);FeNO at 2 and 3 months after inclusion in repeated asthmatic group showed positive correlation with IL-18 at the same time (P<0.05),and was negatively correlated with IL-33 level (P<0.05);there was no correlation between FeNO and IL-18,IL-33 in healthy control group (P>0.05).Conclusions IL-18 and IL-33 may be involved in the pathogenesis of acute RSV bronchiolitis and recurrent wheezing,and the concentration of IL-18 and IL-33 is correlated with the level of FeNO.Its potential mechanism needs further study.
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With the rapid development of transgenic technology, the safety of genetically modified products has received extensive attention. Certified reference materials for the detection of genetically modified organisms play important roles in ensuring comparability and traceability of the qualitative and quantitative detection of genetically modified products. However, the development of protein reference materials is relatively slow, and one of the difficulties is the preparation of protein candidates with high purity. The cry1Ah1 gene of Bacillus thuringiensis has been used for the development of transgenic insect-resistant crops because of its excellent insecticidal activity against lepidopteran pests such as Asian corn borer, and has obtained transgenic lines with good insect resistance traits. In order to develop Cry1Ah protein certified reference material, it is urgent to establish a preparation and purification system. In this study, a system for preparing Cry1Ah protein by Bt expression system was optimized, and a high-purity Cry1Ah protein (size exclusion chromatography purity: 99.6%) was obtained by ion-exchange chromatography and size exclusion chromatography stepwise purification. The results of biological activity assay showed that there was no significant difference in the insecticidal activity of purified Cry1Ah protein and protoxin against diamondback moths (Plutella xylostella). Finally, the amino acid sequence of the activated Cry1Ah protein was determined using Edman degradation and mass spectrometry. In summary, the obtained Cry1Ah pure protein can be used for the development of protein reference materials.
Тема - темы
Animals , Bacillus thuringiensis , Bacterial Proteins , Cryptochromes , Metabolism , Endotoxins , Hemolysin Proteins , Moths , Pest Control, Biological , Plants, Genetically ModifiedРеферат
Objective To establish the quality standard for Bushen-Tongluo granules.Methods Drynariae rhizoma, Paeoniae radix alba, Cyathulae radix, Chuanxiongin rhizome were identified by thin layer chromatography (TLC), and the content of naringin and paeoniflorin was determined by high performance liquid chromatography(HPLC) with chromatographic column Agilent C18 (4.6 mm×250 mm, 5 μm), as the mobile phase was acetonitrile-0.1% phosphoric acid and the scan wave length were 230 and 283 nm. The column temperature was 30 . The flow rate ℃ was 1.0 ml/min. Results TLC could identify Drynariae rhizoma , Paeoniae radix alba, Cyathulae radix, Chuanxiongin rhizome effectively. Under the condition, there was a good linear relationship when the content of naringin was in 6.337 0-50.695 7 μg. There is also a good linear relationship when the content of paeoniflorin was in 26.065 8-130.328 8 μg. The average recovery rate of naringin was 97.13% and RSD was 1.19%.The average recovery rate of paeoniflorin was 96.61% and RSD was 1.51%. Conclusions The established methods are simple, specific, reproducible, and sensitive, and they can be used for the quality control of Bushen-Tongluo granules.
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Objective To establish an HPLC method for simultaneous determination of Quercetin , Luteolin, pigenin in Matricaria Chamomila L.. Methods HPLC analysis was performed on Agilent Zorbox SB-C18 column (4.6 mm×250 mm, 5 μm) with the methanol and phosphoric acid as mobile phase in equal degree model, and the column temperature was set at 25 ℃, and the flow rate was 1.0 ml.min-1 and the detecting wave length was at 350 nm. Results The linear response ranges were from 0.25-4.04 μg of Quercetin (r=1.000, n=6) and from 0.25-3.98 μg of Luteolin (r=1.000, n=6) and 0.25-4.02 μg of Apigenin (r=1.000, n=6);and the recoveries, the precision and the stability RSD of Quercetin, Luteolin and Apigenin meet the requirements. The average recovery rate of quercetin, luteolin and apigenin was 93.64%, 95.85% and 95.40%, respectively. Conclusions All 3 samples in Matricaria Chamomila.L were determined by HPLC. The method is simple, rapid, and reproducible. It can be used as reference for the quality control of Matricaria Chamomila L..
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Objective To investigate the clinical effect of proximal femoral nail anti rotation intramedullary nail (PFNA)in the treatment of intertrochanteric osteoporotic fractures in elderly patients.Methods 42 cases of femoral intertrochanteric fracture were treated with proximal femoral nail anti rotation intramedullary nail (PFNA)in cases (AO type,A1 type 13 cases,A2 type 24 cases,type A3 5 cases).Results The group of 42 patients after 12 -36 months of follow -up,the average follow -up time of 18 months,all the patients were healed,1 case of deep venous thrombosis,1 case of mild coxa vara.According to the Harris evaluation standard:excellent 32 cases,good in 9 cases,fair in 1 case,the excellent rate was 97.6%.Conclusion The proximal femoral nail anti rotation (PFNA) anti tensile,anti sliding and anti rotation function is good,and has the advantages of simple operation,small trauma,for osteoporotic intertrochanteric fracture patients can be applied.
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Objective To investigate the association of chromosome 8p copy number alteration (CNA) with postoperative survival of patients with hepatocellular carcinoma (HCC),and to screen for possible target genes in the survival-related CNA (s) in 8p.Methods 187 HCC patients were enrolled into the study,which included 66 patients whose follow-up data were available and the follow-up was 2.6 ~ 73.3 months.High-resolution Agilent 244K comparative genomic hybridization (CGH) and Affymetrix U133 Plus2.0 expression arrays were used to screen for CNAs and gene expression differences in 8p.The associations between CNAs in 8p and survival were analyzed using the log-rank test,Kaplan-Meier survival analysis and Cox proportional hazards models.The gene expression levels between the groups were compared by the Mann-Whitney U test.Results Copy number loss on 8p12 (31/66,47%) was significantly associated with reduced survival rate,and HCC patients with 8p12 loss had a 4.1-fold (95% CI =1.8 ~ 9.4,P < 0.05) increased hazard ratio (HR) for death from HCC,as compared to those without the loss.The mRNA expression levels of the 3 genes in 8p12,including TMEM66,DCTN6,and MAK16,were significantly decreased in HCCs with gene loss than in HCCs without the loss (all P < 0.05),and in non-tumorous liver tissues (all P < 0.05).Conclusion Loss of 8p12 is an independent prognostic marker of unfavorable survival for patients with HCC,and underexpression of genes TMEM66,DCTN6,and MAK16,owing to 8p12 loss,contributed to unfavorable prognosis.
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Objective To prepare and optimize insulin-loaded N-trimethyl chitosan nanoparticles via orthogonal design , and preliminarily study the effects on blood glucose level .Methods The insulin-loaded N-trimethyl chitosan nanoparticles (INS-NPs) were prepared by ionic gelation ,and the optimal proportion was obtained with orthogonal design .The nanoparticles were characterized by transmission electron microscopy and zeta/sizer nano analyzer .The entrapment efficiency of insulin-load-ed nanoparticles and the in vitro releasing characteristics were studied by HPLC .A preliminary pharmacodynamic study of the insulin-loaded nanoparticles was also carried out .Results The INS-NPs exhibited narrow distribution .The mean diameter of INS-NPs was (63 .26 ± 1 .88)nm ,while the entrapment efficiency was (37 .92 ± 2 .11)% .After 8 hours of subcutaneous injec-tion of the INS-NPs ,the blood glucose level in diabetic rats decreased to normal level and kept stable .Conclusion The opti-mized insulin-loaded nanoparticles had homogeneous spherical shape ,small size ,and could be a new approach of administration for insulin .
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Objective To study the influence of the early ambulation on postoperative patients' comfort and complications with the femoral artery puncture interventional therapy.Methods After searching for related literatures with computer,we evaluated the quality of the literatures and screened them.12 random controlled trials met the inclusion criterion.Using RevMan 5.1.2 software,we respectively made Meta analysis for patients with sense of comfort and complications after operations.Results Compared with the control groups,the experimental groups were better in back pain,abdominal pain,limb numbness and acid bilges,sleep disorder,dysuria and urinary retention than those of the control groups.And the difference in the site of puncture bleeding and hematoma had no statistical significance between the two groups.Conclusions It can improve comfort for patients without increasing incidence rate of complications by lying in bed and rest for 12 hours after interventional therapy.It reflects the patient-centered nurs-ing service concept and can improve the patients' quality of life.
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Objective To investigate the current situation of psychological capital and job burnout of psychiatric nurses and explore the relationship between psychological capital and job burnout.Methods There were 142 psychiatric nurses collected in the study by convenience sampling.The Psychiatric Capital Questionnaire (PCQ) and Nurse Burnout Scale (NBS) were used to measure the level of psychiatric capital and job burnout of psychiatric nurses.The Pearson correlation analysis was used to explore the relationship between psychological capital and job burnout.Results The psychological capital of psychiatric nurses had a negative correlation with job burnout; the higher of the nurses' psychological capital,the lower their sense of job burnout,vice versa.Conclusions In order to improve nursing quality,nursing managers can reduce the job burnout by improving the psychological capital of psychiatric nurses.
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Objective To compare plasma concentrations of biomarkers of endothelial dysfunction between patients with primary aldosteronism (PA) and essential hypertension (EH),and to determine whether elevated levels of these biomarkers could predict development of early organ damage .Methods 56 PA patients ( the observation group) and 56 EH patients(the control group) matched for age,sex,blood pressure and duration of hypertension were included in this study .The plasma levels of biomarkers reflecting endothelial dysfunction [ von Willebrand factor (vWF),soluble intercellular adhesion molecule 1(sICAM-1),oxidized low density lipoprotein(ox-LDL)]were detec-ted and compared between PA and EH patients .The left ventricular mass index ( LVMI) determined by echocardio-graphy,24-hour urinary protein quantitative determination and urinary albumin excretion rate ( UAER) were analyzed to evaluate early organ damage .Results ( 1 ) In the observation group , the plasma markers of endothelial damage vWF (133.4 ±54.9)%,sICAM-1 (412.1 ±75.2)μg/L and ox-LDL (13.7 ±9.0) U/L levels were higher than those in the control group(t=4.642,3.955,2.843,all P<0.05),and the observation group had a higher 24 h urina-ry protein(t=2.042,P<0.05) and LVMI(t=7.235,P<0.05).(2)Correlation analysis showed that LVMI was positively correlated with PAC,ox-LDL,vWF (r=0.447,0.385,0.393,P=0.020,0.046,0.029),and was nega-tively correlated with admission blood K +(r=-0.294,P<0.05).UAER was positively correlated with PAC,vWF and sICAM-1 (r=0.622,0.389,0.499,all P<0.05),and was negatively correlated with admission blood K +(r=-0.314,P<0.05).Conclusion Patients with PA have severer endothelial dysfunction reflected by multiple bio-markers and earlier organ damage than patients with EH ,and plasma aldosterone concentration and multiple endotheli-al dysfunction biomarkers could independently predict early organ damage .
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Objective To investigate the job burnout of the psychiatric nurses and to explore the relationship between job burnout and self concept,self-efficacy,social support for the psychiatric nurses.Methods A total of 130 psychiatric nurses who worked in Wuhan were investigated with Maslach Burnout Inventory (MBI),Tennessee Self-Concept Scale (TSCS),General Self-Efficacy Scale (GSES) and Social Support Scale (SSRS).The SPSS17.0 software was used for statistical analysis.We employed the job burnout dimensions as the dependent variable,while the self concept,self-efficacy and social support as the independent variable to establish the regression model.Results The job burnout of psychiatric nurses in terms of gender,marital status,education and professional tides had significant differences.Emotion exhaustion had negative correlation with self concept,self-efficacy and social support,depersonalization also had negative correlation with these three dimensions,while personal achievement had positive correlation with these three dimensions.Conclusions There is job burnout in emotion exhaustion,depersonalization,and personal achievement among psychiatric nurses.Nursing managers in psychiatric departments should pay more attention to enhance nurses' own ability and improve the level of nurses’self-concept,self-efficacy and social support,in order to reduce the job burnout.
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Objective To investigate the relationship between the cerebral circulation time and disease condition and prognosis in patients with acute subarachnoid hemorrhage. Methods DSA were performed to determine the cerebral circulation time (CCT) in 60 patients who had subarachnoid hemorrhage (SAH) within 3 days. The patients were divided into different groups according to the severity of the disease condition,patients with CSC score as 13-15 were assigned as group Ⅰ ,whose CCT was (13.45 ± 1. 89) s. Twenty two patients with GSC score as 3-12 were assigned as group Ⅱ ,whose CCT was (16.79 ± 2. 07) s. There were significant difference between the CCT of the two groups (t =3. 76,P = 0. 001). (2)Twenty-nine patients with Hunt-Hess grade as 1-2 were assigned as group 1,whose CCT was (13.06 ± 1. 83) s. Thirty one patients with Hunt-Hess grade as 3-5 were assigned as group 2, whose CCT was (15. 89 ± 2.06) s. There were significant difference between the CCT of the two groups (t = 3. 39, P =0. 003). (3) Seventeen patients with delayed ischemic damage were assigned as group A, whose CCT was (16. 84 ±1.91) s. Forty three patients without delayed ischemic damage were assigned as group B, whose CCT was (12.94 ± 1. 67) s. There were significant difference between the CCT of the two groups (t = 2. 23, P =0.025). (4)Forty-six patients with GOS score as 4-5 were assigned as group a,whose CCT was (13.07 ±1. 89)s. Fourteen patients with GSC score as 1-3 were assigned as group b,whose CCT was (17.11 ± 1. 71)s. There were significant difference between the CCT of the two groups (t = 3. 27, P = 0.008). Conclusion CCT may reflect the severity of the SAH in early onset patients and has prognostic value.
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This study examined the wave intensity (WI) of the carotid artery in patients with hyperthyroid in order to assess the hemodynamic changes of hyperthyroid patients. A total of 86 hyperthyroid patients without cardiac morphological changes and arrhythmia, and 80 healthy control subjects were enrolled in the study. Right common carotid artery (RCCA) was selected for ultrasonic imaging to obtain WI indices, including amplitude of the peak during early systole (W1), amplitude of the peak during late systole (W2), area of the negative wave during mid-systole (NA), interval between R wave of electrocardiogram and W1 (R-1st), interval between W1 and W2 (1st-2nd). The levels of serum thyroid hormones, consisting of free triiodothyronine (FT3), free thyroxin (FT4) and thyroid stimulating hormone (TSH), were measured in hyperthyroid patients. Echocardiographic indices including left ventricular ejection fraction (LVEF) and left ventricular fraction shortening (LVFS) were determined in each subject. The results showed that the W1, W2, NA, and (1st-2nd×HR) in hyperthyroid patients were significantly higher than those in healthy controls. There was no significant difference in LVEF and LVFS between the two groups. FT3 was correlated with W1, W2, NA, (1st-2nd×HR), pulse pressure (PP) and heart rate (HR) in hyperthyroid patients. Several abnormal waves on WI curves were present in 19 hyperthyroid patients during mid-systole. It was concluded that WI technique may prove a real-time, noninvasive, sensitive and convenient tool for assessing the cardiac function and hemodynamic alterations in hyperthyroid patients.
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AIM: To investigate the effect of chronic intermittent hypobaric hypoxia (CIHH) on the activity of adrenergic receptor(AR) in rabbit sino-atrial node (SAN) by intracellular recording.METHODS: New Zealand rabbits were randomly divided into three groups: control group (Con), 14 d CIHH treatment group (CIHH14) and 28 d CIHH treatment group (CIHH28). The CIHH rabbits were exposed to a simulated 5 000 m (oxygen 11.1%) hypobaric hypoxia in hypoxic chamber for 14 d or 28 d (6 h/d), respectively. SAN preparation was used and the transmembrane action potential was recorded by micropipettes. Isoproterenol hydrochloride (ISO, agonist of β-AR) and phenylephrine (PE, agonist of α_1-AR) at different concentrations (0.01, 0.1 and 1 μmol/L) were applied cumulatively to investigate the electrophysiological effect of the drugs on the rabbit SAN among Con, CIHH14 and CIHH28 groups, respectively. RESULTS: (1) CIHH didnt change the parameters of action potential of SAN recorded under basic condition. (2) ISO changed some parameters of AP significantly in a dose-dependent manner, including increases in the amplitude of AP (APA), maximal rate of depolarization (V_(max)), the velocity of diastolic (phase 4) depolarization (VDD), and rate of pacemaker firing (RPF). (3) The response of AP to ISO in CIHH rabbits was decreased significantly compared to that in Con animals. Under 1 μmol/L of ISO, the increases in VDD, RPF, APA and V_(max) in CIHH animals were smaller than those in Con animals (P<0.05). (4) No effect of PE (0.01, 0.1 and 1 μmol/L) on the parameters of action potential was observed. CONCLUSION: CIHH decreases the reactivity of β-AR, but has no effect on α_1-AR in SAN of rabbit.
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Objective To observe hemodynamic changes in patients with primary hypertension with wave intensity (WI). Methods Carotid arteries of 36 patients with primary hypertension and 30 age-matched normal controls were examined with imaging technique of WI. The following parameters were measured: the first wave peak in early ejection (W1), the second wave peak in late ejection (W2), the negative area during the mid-ejection (NA), the interval between the R wave of the ECG and the first peak of W1 (R-1st), the interval between the first peak and the second peak (1~(st)-2~(nd)), the ratio of R-1st and a cardiac cycle time R-1_(HR)~(st)) and the ratio of 1~(st)-2~(nd) , as well as one cardiac cycle time (1~(st)-2(_(HR)~(nd)). Results ①W1 in primary hypertension group increased compared with those of normal controls (P<0.01), while no significant difference of W2, NA, R-1st, 1~(st)-2~(nd), R-1_(HR)~(st), 1~(st)-2_(nd)~(HR) was detected (P>0.05). ②Both W1 and W2 correlated positively with pulse pressure (PP) and systolic blood pressure (SBP) (r=0.66, 0.55, P<0.01;r=0.62, 0.44, P<0.01). W1, W2 and age, DBP were not related significantly (P>0.05). Conclusion The hemodynamic parameters of WI technology provide a new way to evaluate the dynamics of the heart and vascular system and their interaction.
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Objective To investigate the effect of mesenchymal stem cells (MSCs) on subcutaneous xenograft tumors in mice with Lewis lung cancer. Methods MSCs isolated from bone marrow of C57BL/6 mice were made into single cell suspension and were cultured in vitro. The cells of the 4th to 5th passage were used for the subsequent experiments. Fifty six C57BL/6 mice were inoculated subcutaneously with Lewis lung cancer cells, and were grouped into Group D0 (MSCs were given simultaneously with inoculation)and Group D10(MSCs were given 10 d after inoculation). Group D0 included three subgroups (n=8): Group 1 with inoculation of tumor cells, Group 2 with inoculation of tumor cells and MSCs, and Group 3 with inoculation of tumor cells and tail intravenous injection of MSCs. Group D10 included four groups: Group 4 with inoculation of tumor cells and injection of MSCs in tumors, Group 5 with equivalent PBS (the control of Group 4), Group 6 with inoculation of tumor cells and tail intravenous injection of MSCs, and Group 7 with equivalent PBS (the control of Group 6). The time of tumor formation and the volume of tumor were observed and compared among the groups. ResultsIn Group D0, earlier onset of tumor development was observed in Group 2 as compared to Group 1 and Group 3 (P<0.05), while there was no significant difference on the volume of tumor in the three groups (P>0.05). In Group D10, the volume of tumors were larger in Group 4 compared to the control (P<0.05), while there was no significant difference on the volume of tumors between Group 6 and the control (P>0.05). Conclusion Inoculating mixture of MSCs and Lewis lung cancer cells accelerates tumor formation,and injection of MSCs in tumors stimulates the growth of tumors.