To study the influence of different processing technigue in preparing allogeneic bone on proliferation rate and activity of rabbit osteoblasts in vitro, Osteoblasts were cultured combined with allogeneic bone prepared with different processing techniqne. Cell proliferation and activity were assessed 48 and 96h with MTT colorimetry and assay of alkaline phosphatase activity. The results showed that freezed bone (FB) and lyophilized bone (LB) inhibited cell growth and activity, while mineralized bone matrix (DBM),bone matrix gelatin (BMG), and autolyzed antigen extracted allogeneic bone(AAA) enhanced them. With the exception of FB and LB, the three others were biocompatible for osteoblasts.

Objective To provide the effective references for reasonable arrangement of nursing post by comparison on the core competence level and characteristics between the upgraded and the fulltime bachelor nurses.Methods Questionnaire survey based on the basic demographic data and the Competency Inventory for Chinese Registered Nurse for 391 clinical nurses from 13 three level of firstclass hospitals.Results The core competence score of the upgraded and the full-time bachelor nurses showed a moderate degree of satisfaction; the full-time bachelor nurses' total scores were higher than those of the upgraded nurses,and there were statistically significant differences among 6 dimensions included critical thinking and scientific research ability; there was no significant difference in clinical nursing dimension.Conclusions The full-time bachelor nurses' core competence is higher than that of the upgraded nurses in general,but no significant difference exists in clinical nursing dimension.

BACKGROUND:Deep vein thrombosis is a common complication following bone surgeries,so its prevention and treatment become critical.However,there are few studies on the incidence of deep vein thrombosis after spine surgery in the elderly.OBJECTIVE:To explore the diagnosis of deep vein thrombosis after spine surgery in the elderly and its incidence after intervention with low-molecular-weight heparin.METHODS:All patients undergoing spine surgery were randomly divided into experimental and control groups.Patients in the experimental group were subjected to the subcutaneous injection of 0.4 mL of low-molecular-weight heparin (4 100 IU) at 12 hours postoperatively,once daily for 7-14 days from the next day.Those received no intervention served as controls.The thromboplastin time,thrombin time,activated partial thromboplastin time,and level of plasma fibrinogen were detected before and after treatment.Color Doppler ultrasound results of the lower extremity vessel before and after treatment and postoperative drainage volume were recorded.RESULTS AND CONCLUSION:(1) In the experimental group,the lower level of plasma fibrinogen and slightly prolonged thromboplastin time,thrombin time and activated partial thromboplastin time were observed,but all were within the normal range.(2) The incidence of deep vein thrombosis in the experimental group (0％) was significantly lower than that in the control group (5％,P ＜ 0.05).(3) To conclude,low-molecular-weight heparin therapy significantly reduced the incidence of deep vein thrombosis after spine surgery.

Ongoing and rapid development in medical science makes the improvement of English language abilities crucial for students. The paper sets out now to:develop excellent teaching methods, form a qualified and dedicated teaching faculty, focus on individual teaching methods, make English interesting and popular among students, and manage the process to maximize the value of the investment.

Objective To investigate the effect of moderate treadmill exercise together with modified hydroxyapatite chitosan composite hydrogel (CS/HA-g-CS) implantation on repair of full-thickness defects of articular cartilage in rats.Methods Full-thickness cartilage defects were drilled in the patellar groove of bilateral femoral condyles in a total of 24 male SD rats before they were randomly assigned into 4 groups.The control group (BC group) was subjected to no exercise or CS/HA-g-CS implantation;the chitosan group (CHI group) to CS/HA-g-CS implantation without exercise;the moderate treadmill exercise group (MIR group) to exercise 4 weeks after modeling without CS/HA-g-CS implantation;the CHI + MIR group to moderate treadmill exercise plus CS/HA-g-CS implantation 4 weeks after modeling.Half of the animals were sacrificed at week 8 and half at week 16 after operation.Femoral condyles were harvested for gross observation and histochemical measurement by O' Driscoll scoring system.mRNA expressions of glycosaminoglycan,collagen type Ⅱ and BMP-2 were detected by RT-PCR.Results Gross observation revealed:at 8 weeks after modeling,the CHI + MIR group was significantly better than the other 3 groups,with the BC group in the poorest (P ＜ 0.05);at 16 weeks after modeling,the BC group was significantly poorer than the other 3 groups (P ＜0.05) among which there were no significant differences (P ＞ 0.05).O 'Driscoll scoring revealed:at both 8 and 16 weeks after modeling,the CHI + MIR group was significantly better than the other 2 groups and the BC group significantly poorer than the other 3 groups (P ＜ 0.05) but there was no significant difference between the MIR and CHI + MIR groups(P ＞ 0.05).The expressions of collagen type Ⅱ,glycosaminoglycan and BMP-2 were significantly higher in the CHI + MIR group than in the other 3 groups (P ＜ 0.05) and significantly lower in the BC group than in the other 3 groups (P ＜ 0.05).Conclusions Moderate treadmill exercise together with CS/HA-g-CS implantation has significant positive effects on repair of full-thickness defects of articular cartilage in rats than merely moderate treadmill exercise or CS/HA-g-CS implantation alone.The defective cartilage repaired by moderate treadmill exercise together with CS/HA-g-CS implantation contains more collagen type Ⅱ and glycosaminoglycan and shows morphology of nearly normal cartilage.

OBJECTIVE:To investigate the feasibility,safety and efficacy of domestic small waist big edge-type occluder for patients with multiple outlets sac-type membranous ventricular septal defection (VSD),and summarize its technical problems and the choice of treatment strategies.METHODS:A total of 20 patients with sac-type membranous VSD,underwent left ventricular angiography at left anterior oblique 45°-60° plus CAOD 20°-25°;the left ventricular entrance diameters were 7-21 (10.9±5.2) mm,more than 2 outlets in the right ventricular surfaces,and the largest outlet diameters were 3-10 (4.8±2.9) mm.According to the result from transthoracic echocardiography (TTE) and angiography,the sac-bag size,shape,location,extent of tissue adhesion,and stability were determined.Different types of small waist big edge-type occluder were implanted,and the occluder diameter was 5-14 (4.6±2.8) mm.Following 15 minutes of blocking,the immediate effects of occlusion were observed through repeating left ventricuiar angiography and TTE.All patients rechecked ultrasonic cardiography and electrocardiogram at 5-7 days of hospital stay,and 1,3,6 and 12 months following surgery.All patients took aspirin tablets for 6 months.RESULTS:Of 20 patients,17 cases underwent domestic small waist big edge occluder,blocked successfully through left ventricular entrance,2 cases were successful using symmetry block,and 1 case was failed.Intraoperative occlusion did not affect the aortic valve and tricuspid valve function.There were 1 case with left bundle branch block and 1 case with right bundle branch block during the operation,and all recovered within a week by using hormone therapy.After 6 months,the cardiac sizes were reduced to different degrees.CONCLUSION:It is safe and effective to treat multiple outlets sac-shaped membranous VSD with domestic small waist big edge-type occluder.The key technology,according to the sac size,shape,firmness,outlet orientation,import size,and the size of aortic stump,is to determine the block site and to select a suitable occluder.

Objective:To investigate the relationship between primary resection and KRAS gene mutation in the mild symptomatic patients with stage Ⅳ colorectal cancer,and to clarify its significance of prognosis.Methods:The clinical data of 46 mild symptomatic patients with stage Ⅳ colorectal cancer 2010 to December 2010 were collected.All the patients received primary resection.The KRAS gene mutation in the patients was detected by direct sequencing and the patients were followed up for 5 years.The influence of primary resection and KRAS gene mutation in prognosis of the patients with stage Ⅳ colorectal cancer was analyzed, and the clinical pathological features which might influence the prognosis were analyzed by survival analysis.Results:In 46 patients with colorectal cancer, KRAS gene mutation was found in 20 cases, the mutation rate was 43.4%, and most mutation was found at Codon 12. The KRAS mutation had relationship with the tumor site and multiple metastasis (P<0.05).The Kaplan-Meier survival curve and univariate analysis results showed that the median survival time of the patients with wild type of KRAS gene was 58.4 months, the median survival time of the patients with mutant type of KRAS gene was 42.2 months, and there was no significant difference (P>0.05).The median survival time of right colon cancer patients was 34.2 months, the median survival time of left colon cancer patients was 58.3 months, and there was sigificant difference (P<0.05).The cancer metastases including liver, lung and multiple metastasis were closely related to the poor prognosis of the colorectal cancer patients(P<0.05).The median survival time of the patients with stage Ⅳ colorectal cancer was 39.6 months after operation.Conclusion:After primary resection of the mild symptomatic patients with stage Ⅳ colorectal cancer,the median survival time of the patients with colorectal cancer in left colon site and right colon site were prolonged.Right colon cancer has more poorer prognosis than left colon cancer.KRAS gene mutation is associated with the tumor site and the multiple metastasis.The location of metastasis affect the prognosis.

Objective: To examine the mediating effect of frailty on social isolation and cognitive function among the elderly. Methods: Demographic information, smoking, alcohol consumption and cognitive function of the elderly at ages of 60 years and older were collected from the China Health and Retirement Longitudinal Study 2020. Social isolation and frailty were evaluated using social isolation index and frailty index, respectively. The mediating effect of frailty on social isolation and cognitive function was analyzed using the Process program, and the significance of the mediating role was tested using the Bootstrap test. Results: A total of 2 822 individuals were enrolled, including 1 483 males (52.55%) and 1 339 females (47.45%). There were 2 497 (88.48%) and 325 (11.52%) individuals at ages of 60-<75 years and ≥75 years, respectively. The median cognitive function score was 14 (interquartile range, 16) points. There were 432 cases with social isolation (15.31%), with a median social isolation index of 10 (interquartile range, 5) points. The median frailty index was 0.11 (interquartile range, 0.15). There were 1 111 individuals without frailty, accounting for 39.37%; 1 214 individuals with pre-frailty, accounting for 43.02%; and 497 individuals with frailty, accounting for 17.61%. Mediating effect analysis showed that social isolation affected cognitive function directly and negatively with the effect value of -0.773 (95%CI: -0.899 to -0.647), and also affected cognitive function by frailty indirectly and negatively with the effect value of -0.147 (95%CI: -0.188 to -0.110), with the mediating effect contributed 15.98% of the total effect. Conclusion Frailty can directly or indirectly affect cognitive function among elderly through social isolation.

Objective To observe the implementation of national food safety standard for “Iodine Concentration in Edible Salt”(GB 26878-2011) and its effectiveness on iodine nutritional status of key populations. Methods Information of iodine concentration in edible iodized salt of various provinces (autonomous regions and municipalities, including Xinjiang Production and Construction Corps) was collected using Baidu Searching Engine through the establishment of key words. Sal t samples were collected in Tianjin City and Aksu Region of Xinjiang , and the salt iodine concentration in both places was 30 mg/kg. In Tianjin, Hongqiao, Tanggu and Hangu, Beichen were selected as representatives of the downtown areas, the coastal areas and the suburbs, respectively and counties of Baodi and Ji were iodine deficiency areas in history. Sampling work was carried out from August 2012 to March 2013 in Tianjin. In Aksu, Yatuoer Township and Charqi Town in Baicheng County, Aotebeixi and Aketuohai Townships in Wushen County were chosen as iodine deficiency areas, and the survey was carried out from January to September 2013 . Random urine samples of school-age children ( 8 - 10 years old ) , pregnant women and lactating women were collected; urinary iodine was measured following the Method for Determination of Iodine in Urine by As3+-Ce4+ Catalytic Spectrophotometry(WS/T 107-2006) and iodine in edible iodized salt was measured following the General Test Method in Salt Industry Determination of Iodideion ( GB/T 13025 . 7-1999 ) . Results Fourteen of the provinces(autonomous regions and municipalities, including the Corps of Xinjiang) chose 25 mg/kg as their iodine concentration in edible iodized salt and 13 provinces chose 30 mg/kg. Besides, there were another 5 provinces providing 30 mg/kg particularly for pregnant women and lactating women while 25 mg/kg for other populations. In Tianjin, the medians of iodine concentration in edible iodized salt were ranged from 24.4 - 32.1 mg/kg in retail stores and 26.4 mg/kg at households. The household coverage rate of iodized salt and the proportion of households using adequately iodized salt were 78.5%(168/214) and 62.6%(134/214), respectively. The median ranges of urinary iodine were 178.2 - 183.9 μg/L in school children, 124.3 - 130.9 μg/L in pregnant women and 72.7 - 109.5 μg/L in lactating women. In Aksu, the medians of iodine concentration in edible iodized salt were 27.1 and 26.5 mg/kg in retail stores and households, respectively. The household coverage rate of iodized salt and the proportion of households using adequately iodized salt were 100.0% (363/363) and 98.9%(359/363), respectively. The median ranges of urinary iodine were 174.8 - 293.0, 154.9 - 230.0 and 135.8 - 239.3 μg/L among school children, pregnant women and lactating women, respectively. The median of iodine concentration in a special edible iodized salt sample reached 49.1 mg/kg, and qualified rate was 0(0/11) in Aksu. Conclusions All provinces , municipalities and autonomous regions ( including the Corps of Xingjiang ) in China have adjusted the iodine content in edible iodized salt in accordance with GB 26878-2011. However, in Tianjin the household iodine concentration in edible salt is lower than the local standards; the household coverage rate of iodized salt and the proportion of households using adequately iodized salt are lower than the national standards; pregnant women and lactating women are at risk of mild iodine deficiency.

Objective To prepare a new thrombus model by fluid model method , which is suitable for evaluation of mechanical thrombectomy devices for acute stroke.Methods The fluid model adopted the Chandler loop theory , while the static model adopted conventional method.Mechanical properties of thrombi prepared by fluid model and static model were measured by manual elongation test ( 15 samples in each group) and catheter injection test (15 samples in each group ).Histological structure was compared among the above thrombus models ( 5 samples in each group ) and specimens of five patients with stroke by hematoxylin-eosin staining method.Then, thrombi in fluid model were utilized to establish embolization of vessels in swine model ( two pigs ) for evaluation of radiopacity.Independent-Sample test was performed to compare the maximum tensile length of two methods , and Fisher′s exact test was used to compare the rate of thrombus fragmentation after catheter injection test.Results The maximum tensile length of two models were (4.28 ±0.23) and (3.16 ±0.13) cm, respectively, and the difference was statistically significant (t=16.38, P<0.01);After catheter injection, the fracture rates of thrombus were 13% (2/15) and 60%(9/15), which were also statistically significant (P<0.05).As to histological structure, thrombi prepared by fluid model showed mixed thrombus structure , which similar to thrombi of stroke patients , But thrombi prepared by static model were replete with erythrocytes under the microscope .A total of eight vessels ( lingual arteries and superficial cervical arteries ) in two swines were successfully occlusive ( TIMI 0 or 1 ) , and sufficient radiopacity of each injected thrombus was observed.Conclusions The thrombi prepared by fluid model not only have good mechanical stability and sufficient radiopacity , but their histological structure is similar to thromboemboli retrieved from cerebral arteries of patients with acute stroke.