Objective To investigate the effect of electric stimulation applied during absolute refractory period on contraction and relaxation and Ca 2+ transient of ventricular myocytes from normal guinea-pigs. Methods The ventricular myocytes of guinea-pigs were obtained by enzyme digesting, and the extent of the contraction and relaxation and Ca 2+ transient were recorded through the motion edge detection system. The Ca 2+ transient was reflected by fluorescence ratio (360/380) ( F 360/F 380). Results The ventricular myocytes from the normal guinea-pigs: ①The contraction extent of guinea-pig ventricular myocytes increased by (16.55?5.49)%. The peak velocity of shorting (contraction) and the peak velocity of relengthening (relaxation) increased by (17.43?7.08)% and (19.74?9.08)%, respectively(n=10); ②The extent of F 360/F 380 increased (25.79?6.88)%. The peak velocity of F 360/F 380 increased by (29.47?9.25)% and (22.52?7.81)% during shortening and relengthening, respectively(n=10). The ventricular myocytes from failure guinea-pigs: ①The contraction extent of guinea-pig ventricular myocytes increased by (15.53?5.31)%. The peak velocity of shortening (contraction) and the peak velocity of relengthening (relaxation) increased by (10.60?3.02)% and (23.32?8.26)%, respectively(n=6); ②The extent of F 360/F 380 increased (16.82?7.03)%. The peak velocity of F 360/F 380 increased by (16.27?5.91)% and (10.32?2.46)% during shorenting and relengthening, respectively(n=6). Conclusion Appropriate electric stimulation applied during absolute refractory period might strengthen the contracting and relaxing function of normal and failing ventricular myocytes in guinea-pigs.

Objective To study the optimal technology parameters of the enrichment process for total flavonoids of Crataegus pinnatifida Bge,with macroporous Resin. Methods The enrichment process was studied by orthogonal experiment design using orthogonal from L9(34) with the content of total flavonoids from Crataegus pinnatifida Bge,as indexes, the factors such as adsorption capacity, the column diameter-height ratio, eluant volume and adsorption time were investigated. Results The optimum elution parameters were as follows: the eluant volume of 60% alcohol—the wet resin amount (g)—the sample volume (mL) was 2:1, the sample was 4:1, the column diameter-height ratio was 1:6 , the adsorption time was 1h, respectively. Conclusion This process enriching the total flavonoids of Crataegus pinnatifida Bge,is feasible.

Objective To explore the correlation between hepatitis B virus large surface protein(HBV-LP)and hepatitis B virus deoxyribonucleic acid(HBV-DNA),analyze the clinical significance of detecting the two index dynamically for diagnosis and treatment of hepatitis B.Methods Enzyme linked immunosorbent assay(ELISA)and fluorescent quantitation polymerase chain reaction(FQ-PCR)were used to detect the levels of HBV-LP and HBV-DNA in serum specimen of 230 hepatitis B patients.Results There was a positive correlation between the content of HBV-LP and copy numbers of HBV-DNA in serum of hepatitis B positive cases(r=0.84,P＜0.01).The positive rate was 84.78％ in HBV-LP and 84.35％ in HBV-DNA of 230 HBV positive cases.As a result there was no significant difference(P＞0.05)in this study.Therefore,the positive rate was 63.63 ％(35/55)in HBV-LP and 58.18％(32/55)in HBV-DNA of 55 HBV negative cases.There was also no significant difference(P＞0.05)in this study.However,the positive rate of HBV-LP(82.47％)was higher than HBE(52.06％)in the 194 HBV-DNA positive cases.There was significantly different(P＜0.01).Conclusion HBV-LP and HBV-DNA are the significant index of the degree of hepatitis B virus replication in hepatitis B positive cases,especially in determining the virus replication and prognosis of treatment in HBe Ag negative,providing the reliable laboratory data for the clinical diagnosis and treatment.

Objective:To investigate the animal model of guinea pig chronic heart failure and compensatory hypertrophy. Methods:Thirteen chronic heart failure models were made by placing a constricting band around the ascending aorta of guinea pigs,raised in the same house of 10 normal guinea pigs. The contrasting indexes in 6 weeks include: clinical features, hemodynamics, the mass ratio of ventricular over body, the width of left ventriculat hypertrophy. Results:One model died, 4 models without dyspnea showed increasing in left ventricular pressure and the mass ratio of ventricular over body, whereas the left ventricular end diastolic pressure showecl no significant different. Eight models with dyspnea showed striking increasing in left ventricular pressure and left ventricular end diastolic pressure, as well as the mass ratio of ventricular over body and the width of left ventricular hypertrophy. Conclusion:The animal model of guinea pig chronic heart failure and compensatory hypertrophy may be formed by constricting the ascending aortas of guinea pigs for 6 weeks.

Objective To investigate the normal range of the femoral neck α-angle in normal Chinese adults and classify the morphology of the anterior femoral head-neck junction on CT-based images. Methods Six hundred and fifty-two adult patients (Bilateral: 459 patients, unilateral:193 patients) with the total of 1111 hips (552 left; 559 right, and 654 male; 457 female) without known diseases affecting the proximal femur or symptoms of femoroacetabular impingement (FAI) underwent 64-slice CT scanning for medical purpose with the hip included in the scan range. The volume CT data was used for further analysis in this study. Oblique sagittal plane images paralleling to the axis of the femoral neck were reconstructed with the volume CT data, the image through the middle of the femoral neck was chosen to measure α-angle with AutoCAD2006 software. The morphology of the anterior femoral head-neck junction was classified. Analysis of variance and t-test were performed with SPSS 15.0. Results The mean value of α-angle of all 1111 hips was 38. 2° ±5.3°. The normal range of α-angle in Chinese adults was 28°to 49°.The mean value of left and right α-angles were 38. 0° ±5. 3°and 38.4° ±5. 3° ,respectively, and there was no statistically significant difference between both sides (t = - 1. 231 ,P ＞ 0. 05 ). Males have greater α-angles than females 39. 2° ±5. 8 vs 36. 8° ±4. 1°, with t = -8. 180, P ＜0. 01. There was no statistically significant differences of the α-angles of the seven age groups (F = 1. 765, P ＞ 0. 05 ). In all 1111 proximal femora, 168 were classified as concave type, accounting for 15. 1%, with a mean α-angle of 31.2° ±2. 0°,726 were smooth type, accounting for 65.4%, with a mean α-angle of 37.4° ± 2. 4°, and 217 were flat type, accounting for 19.5%, with a mean α-angle of 46. 4° ±3. 8°. The differences of the α-angles of the three groups reached statistical significance ( F = 1636. 107, P ＜ 0. 01 ). Conclusions The morphology of anterior femoral head-neck junction can be classified into three types: concave type (type Ⅰ ), smooth type (type Ⅱ ) and flat type (type Ⅲ ). This classification could directly reflect α-angle, which helps to recognize the variation of the offset of anterior femoral head-neck junction. This study offers basic data for the diagnosis of FAI.

AIM: To investigate the influences of electric stimulation applied during the absolute refractory period (ARP) on the cardiac function of normal rabbits and rabbits after myocardial infarction (MI) and to observe the regional effects of this electric stimulation. METHODS: 64 rabbits were randomly assigned to normal and MI groups and each group was then divided into the anterior and posterior groups. A thoracotomy was performed 4 weeks after MI in rabbits. One set of electrodes was inserted into the anterior and posterior wall of left ventricle of the anterior and posterior groups, respectively. Current pulses were delivered during the ARP (called CCM) during sinus rhythm in rabbits. The left ventricular systolic pressure (LVSP) and the left ventricular end diastolic pressure(LVEDP) as well as maximum positive and negative left ventricular pressure change (?dp/dt_(max)) were observed. RESULTS: In the normal and MI groups, LVSP, +dp/dt_(max) significantly increased, and LVEDP, -dp/dt_(max) were reduced during CCM stimulation compared with the baseline (P0.05). CONCLUSION: Electric stimulation delivered during the ARP significantly enhances the contractility and the relaxation of myocardium in normal rabbits and rabbits after MI, and the effects of CCM stimulation on heart are regional. [

Objective Using CT three-dimensional image technique to observe the pulmonary vein stenosis of circumferential pulmonary vein ablation (CPVA) for atrial ifbrillation (AF) on the structure of pulmonary vein before and after radiofrequency ablation. Methods 28 patients with AF who underwent CPVA were followed-up for a mean (6.5±3.9) months.The results of Pulmonary vein morphology study was compared with analysis of preablation, after following up radiofrequency catheter alation (6.5±3.9) months. Pulmonary vein diameters, cross-sectional area and left atrial volume were measured before and after CPVA using 64-slice multidector computed tomography (CT). Results Mild stenosis of pulmonary vein maximum diameter and pulmonary minimum diameter were 61.6%and 56.3%after CPVA. Moderate stenosis of pulmonary vein maximum diameter and pulmonary minimum diameter were 3.6%and 5.4%. All patients does not present symptoms of pulmonary vein stenosis at rest on during excercise during follow up. Conclusions Mild and moderate asymptomatic pulmonary vein stenosis may present in some patients after CPVA.

Objective: To study the MRI manifestations of foot injuries in amateur marathoners and the diagnostic value of MRI for foot injuries. Methods: Forty-eight amateur marathoners were prospectively recruited from October 2018 to March 2019. Participants were grouped according to the FASS criteria. All participants underwent bilateral foot MRI examinations. The MRI features of foot in amateur marathoners with and without foot pain were analyzed.The association with gender, age, time to participate in marathon, amount of running per week, number of times to complete the whole marathon and the symptoms of foot pain was studied. Results: There were 28 sides in FASS in grade 0, including 8 males and 20 females, 8 hydrocele of the first metatarsophalangeal joint, 6 edema of bone marrow, 4 edema of soft tissue, 4 hydrocele of tendon sheath, and 6 without abnormal manifestations of MRI. There were 68 sides in FASS grade 1, including 42 males and 26 females, 38 Achilles tendinitis, 14 plantar fasciitis, 12 Achilles tendon bursitis and 4 posterior ankle impingement syndrome. The incidence of foot pain in amateur marathoners was related to gender (OR=1.060, P=0.043), unrelated to age (OR=0.248, P=0.078), number of marathons completed (OR=1.006, P=0.956), time to participate in marathon (OR=1.008, P=0.944), amount of running per week (OR=0.971, P=0.407). Conclusion Among amateur marathon runners, the foot pain is mainly caused by Achilles tendon and plantar fascia, while those without foot pain are mainly characterized by joint effusion, tendon sheath effusion and bone marrow edema. Gender is the only factor affecting the incidence of foot pain in amateur marathoners. MRI examination is an effective method to determine foot injury and has important clinical application value in the diagnosis and treatment of foot injury.

Objective To study the MRI manifestations of foot injuries in amateur marathoners and the diagnostic value of MRI for foot injuries. Methods Forty?eight amateur marathoners were prospectively recruited from October 2018 to March 2019. Participants were grouped according to the FASS criteria. All participants underwent bilateral foot MRI examinations. The MRI features of foot in amateur marathoners with and without foot pain were analyzed.The association with gender, age, time to participate in marathon, amount of running per week, number of times to complete the whole marathon and the symptoms of foot pain was studied. Results There were 28 sides in FASS in grade 0, including 8 males and 20 females, 8 hydrocele of the first metatarsophalangeal joint, 6 edema of bone marrow, 4 edema of soft tissue, 4 hydrocele of tendon sheath, and 6 without abnormal manifestations of MRI. There were 68 sides in FASS grade 1, including 42 males and 26 females, 38 Achilles tendinitis, 14 plantar fasciitis, 12 Achilles tendon bursitis and 4 posterior ankle impingement syndrome. The incidence of foot pain in amateur marathoners was related to gender(OR=1.060, P=0.043), unrelated to age(OR=0.248, P=0.078), number of marathons completed(OR=1.006, P=0.956), time to participate in marathon(OR=1.008,P=0.944), amount of running per week (OR=0.971,P=0.407). Conclusion Among amateur marathon runners, the foot pain is mainly caused by Achilles tendon and plantar fascia, while those without foot pain are mainly characterized by joint effusion, tendon sheath effusion and bone marrow edema. Gender is the only factor affecting the incidence of foot pain in amateur marathoners. MRI examination is an effective method to determine foot injury and has important clinical application value in the diagnosis and treatment of foot injury.

Objective:To understand the incidence and genetic characteristics of thalassemia in newborns in Baisha Li Autonomous County, Hainan Province, and to provide data support for government decision-making departments to formulate appropriate policies for prevention and control of thalassemia.Methods:With the help of Newborn Disease Screening Network of Hainan Province, samples of dry blood spots on the heels of newborns born in Baisha Li Autonomous County from January to June 2020 were collected based on the principle of informed consent. Fluorescent PCR melting curve method was used to detect the common types of thalassemia genes in Chinese population, and some samples were verified by the PCR + flow-through hybridization method. Samples of suspected new or rare mutations were sent to gene companies for sequencing analysis.Results:A total of 391 samples of neonatal dry blood spots were collected, and 252 samples with thalassemia genes were detected, the detection rate was 64.45% (252/391). Among them, 213 samples with α-thalassemia genes were detected, and the detection rate was 54.48% (213/391); 13 samples with β-thalassemia genes were detected, and the detection rate was 3.32% (13/391); 26 samples with α- and β-thalassemia genes were detected, and the detection rate was 6.65% (26/391). Among the above mentioned thalassemia genotypes, 1 case of rare type α-thalassemia -α 4.2/HKαα and 1 case of rare type β-thalassemia β CD39/β N were detected. According to ethnicity, 176 samples with thalassemia genes were detected in 238 Li samples, with a detection rate of 73.95% (176/238); 67 samples with thalassemia genes were detected in 137 Han samples, with a detection rate of 48.91% (67/137); 9 samples with thalassemia genes were detected in 16 other ethnic samples, with a detection rate of 56.25% (9/16). Conclusions:The detection rate of neonatal thalassemia genes is relatively high in Baisha Li Autonomous County, Hainan Province, and α-thalassemia is the most common. It is recommended that relevant government departments of Hainan Province should carry out genetic testing of neonatal thalassemia in Baisha Li Autonomous County as soon as possible to ensure the quality of life of the newborns.