Multilevel models are applicable to both the quantitative data and categorical variables. We used the methods, including the multilevel models, analysis of covariance and CMH chi-square test, to analyse different types of data, to explore the application of multilevel models in the analysis of the multicenter clinical trial center effect. The results showed that the analysis of covariance is more sensitive to find the center effect for quantitative data, while multilevel models are more sensitive to categorical variables. It can be seen that results with different analytical methods for center effect are not the same, and the most appropriate method should be selected in accordance with the characteristics of data, the objective of research, and the applicable conditions of the various methods in practical use.
Clinical Trials as Topic ; Humans ; Models, Theoretical ; Research Design

The authors briefly introduced the management of clinical test for new drug development, clinical trials for drugs prepared in hospital and post-market drugs, and other types of clinical trials. The mechanism of WHO International Clinical Trial Register Platform (WHO ICTRP), Chinese Clinical Trial Register (ChiCTR) and Chinese Clinical Trial Registration and Publishing Collaboration (ChiCTRPC) were also introduced. The authors suggested the trialists to practice the basic philosophy of evidence-based medicine as the rules of their thought and action, and considered that this is the inner guarantee system for the validity of clinical trials.

[Summary] During recent years, increasing evidences have indicated that type 2 diabetes mellitus(T2DM) might increase the risk of certain tumors; the process might be not only related with the chronic pathologic status of T2DM such as hyperglycemia, hyperinsulinemia, insulin resistance, dyslipidemia, status of chronic inflammation but also associated with the long-term use of anti-diabetic drugs (i. e. sulfonylureas, biguanides, glitazones, dipeptidyl peptidase-4 inhibitors, glucagon-like peptitide-1 receptor agonists), as well as the use of insulin and insulin analogues. Herewith a system review was made about the recent progress in studying T2DM and tumor risk.

0 05)and the consistence rate of 3 000 sera tested by two methods were 99 4% totally, including 99 8%(mixture of speckled and homogeneous), 99 5%( homogeneous) and 99 0%( speckled), respectively Conclusion The difference of ANA results between laboratory caused by test condition such as fluorescence microscopy could be eliminated by using quality control with known fluorescence density So the ANA results may be more precise, reliable and comparable We could, thereby, holisticly improve the quality of ANA detection

Objective To discuss the value of diagnosing gastrointestinal dysfunction in.critically ill children.Methods Seventy-six critically ill patients were reviewed,48 cases combined with gastrointestinal dysfunction.Plasma D-lactate,intestinal fatty acid binding protein(IFABP)of serum and urine were performed in all patients,detected the sensitivity and specificity,ealculated the area under the ROC curve (AUC).Results Plasma D-Iactate level≥9.63 mg/L had a sensitivity of 85.2%,specificity of 70.9%,and AUC of 0.822 for diagnosing gastrointestinal dysfunction.Serum IFABP level≥0.129μg/L had a sensitivity of 65.2%,specificity of 63.8%,and AUC of 0.744 for diagnosing gastrointestinal dysfunction.Urine IFABP ≥0.330μg/Lhad a sensitivity of 78.3%,specificity of 72.3%,and AUC of 0.820 for diagnosing gastrointestinal dysfunction.There was no significant difference in AUC between plasma and urine IFABP(P＞0.05),there was no significant difference in AUC between serum D-lactate and serum IFABP(P＞0.05).Conclusions Plasma D-Lactgte,serum and urine WABP may be useful markers as warning gastrointestinal dysfunction of critically ill children.Plasma D-lactate and urine IFABP level may be more sensitively,but they need to be further studied.

Objective To prepare targeted micorbubble with low immunogenicity. Methods The microbubbles were produced with different phospholipids and identified by the fluorescent method. Detect the level of C3a after reaction with human serum in vitro with enzyme-linked immunosorboent assay (ELISA) method and the number of microbubble binding with the streptavidin packed on the dish by using the parallel plate flow chamber. Results The level of C3a was (1.037±0.047)ng/ml in MBb group,(1. 326 ± 0. 042)ng/ml in MBe group and ( 1.004 ± 0.031 ) ng/ml in MBc group. The level of C3a in MBb group was significantly lower than that in MBe group( P ＜0.05),and there was no significantly difference between MBb group and MBc group ( P ＞ 0. 05). The parallel plate flow experiments showed that the number of MBb(15.2 ± 11.3) in each field of view binding with the streptavidin packed on the dish was significantly fewer than that of MBe ( 103.2 ± 28.3) ( P＜0.05 ), and there was no significantly difference between MBb and MBc(17.8 ± 11.9) ( P ＞0.05). Conclusions The targeted microbubble with low immunogenicity has been prepared successfully,which can be used for further experiment in vivo.

Objective To compare the safety and effectiveness between treatments with autologous platelet gel (APG) versus standard care for treating refractory diabetic dermal ulcers.Methods The 46 patients with proved nonhealing diabetic dermal ulcers were enrolled. Eligible for the study were patients with grade II/III ulcers according to Wagner, lasting for at least 2 weeks and with no signs of infection at recruitment.Patients were given their informed consent document and randomly assigned to two groups: standard care (ST, n=23) or standard care plus topic application of APG (APG, n=23) for twelve weeks.The treatment of blood glucose, blood pressure and lipids was optimized and the empiric antibiotic treatment was further adjusted according to the results of culture and sensitivity testing in all patients. APG treatment consisted of wound dressing with APG, followed by topical washing and cleaning. The APG was then covered with vaseline gauze for 72 hours, after which the ulcers were treated by standard care. Participants were seen thrice a week, twice a week, or at weekly intervals. Twelve weeks observation was set as the end point.Results The would of APG group were improved in 22 patients with ulcers healed completely and 1 case with would area reduced. In the ST group, 13 ulcers were healed, 6 worsened and 4 with would area reduced. The cumulative rate of ulcer healing was 95.7% in the APG group versus 56.5% in the ST group (P=0.002). The total effective rate in APG vs ST group was 100.0% vs 73.9% (P=0.009). By Kaplan-Meier analysis,the time-to-healing of ulcer and time-to-lutation of sinus were significantly different between two groups (log-rank, P=0.006, 0.000, respectively). No treatment-related adverse events were observed. Conclusions Treatment with APG in addition to standard care results in a significantly faster and better healing for a refractory diabetic dermal ulcer and does not raise any safety concerns. So APG treatment can be a valuable and effective aid in the management of diabetic foot ulcers.

Objective　To study the risk factors of pulmonary tuberculosis in Chengdu, Southwest China. Methods　A population-based case-control study was used which included 174 cases selected from 12 communities in Chengdu and 174 controls selected from registered population with normal chest radiograph.Cases were active TB patients which were matched for age,sex with controls,then interviewed by trained interviewers using a standardized questionnaire. Results　Social economic status measured by education, occupation and income did not show obvions influence to TB; It found that the active smoking, passive smoking，type of cigarettes and alcohol consumption had no significanct effects on TB during logistic regression analysis. The study showed that a person who was smoking and also alcohol intake had a higher risk to get TB (OR＝6.12, 95%CI=1.15-32.49). Significant association was showed in the Dose-Response Analysis (OR=1.37, 95％CI=1.30-2.30). Crowded living space (OR=1.14, 95%CI=1.05-1.25), degree of darkness (OR=2.18, 95%CI=1.11-4.27) and moisture (OR=4.06, 95%CI=2.25-7.33), poor sanitary (OR=3.03, 95%CI=1.22-4.44), airpollution of working environment, which were filled with dusts (OR=2.35, 95%CI=1.18-4.70) and chemical fumes (OR=5.15, 95%CI=1.44-18.40) were strongly associated with pulmonary tuberculosis. BMI also had strong relationship with TB (OR=4.72, 95%CI=2.68-8.33). Conclusion　Poor environment and exposure to dust and chemical fume under working condition, low BMI, smoking combining alcohol consumption were the risk factors of adult pulmonary tuberculosis in Chengdu, China.

Objective To evaluate the therapeutic efficacy and safety of radiofrequency ablation (RFA) combined with ethanol injection with a multipronged needle under ultrasound guidance for the treatment of hepatocellular carcinoma (HCC) larger than 3 cm in diameter.Methods 65 patients with 67HCC nodules ranging from 3.1 to 7.0 cm in diameter were treated percutaneously under ultrasound guidance.Tumor response and complications after treatment were observed.Results Complete ablation was achieved in 94.0％ (63/67) of HCC nodules.4 residual tumor nodules received complete ablation after additional treatment.Ablation-related major complications was occurred in 3 patients,including liver abscess in 1 case,abdominal bleeding in 1 case and massive ascites in 1 case,all were cured by conservative therapy.After a mean follow-up period of (20.0 ± 7.6) months (6.7-32.6 months),local-tumor progression was observed in 10 (14.9％) of 67 HCC nodules,and distant recurrence was observed in 32 (49.2％) of 65patients.The 1-year and 2-year survival rate were 93.1 ％ and 88.1％,respectively.Conclusions RFA combined with ethanol injetion with a multipronged needle is a safe and effective technique for the treatment of hepatocellular carcinoma larger than 3 cm,especially 3-5 cm in diameter.

OBJECTIVETo assess the effect of iodised salt for preventing iodine deficiency disorders.

METHODCochrane systematic review.

RESULTSFour randomised controlled trials were included. Subgroup analysis performed lay on different ages, interventions and controls. Prevalence of goitre was reduced close to 5% when using distributed iodised salt and market iodised salt plus iodine oil capsule which showed more effective than using market iodised salt alone (OR = 0.10, 95% CI: 0.02 - 0.17). The latter's prevalence of goitre was 14.7%. When using market iodised salt, the iodine urea excretion level showed different results in children group in different countries. Basically, the market iodised salt for preventing iodine deficiency of pregnancy women were effective, but a part of them did not achieve to the ideal status of iodine nutrition.

CONCLUSIONSThe needs to be strictly controlled quality of iodised salt and market iodised salt plus iodised oil capsule thus can effectively reduce the prevalence of iodine deficiency disorders. However there was not enough evidence to support that market iodised salt can effectively eliminate these disorders, particularly in children. More eligibility trials are needed for providing more evidences.

Adult ; Child ; China ; epidemiology ; Goiter ; epidemiology ; prevention & control ; Humans ; Iodine ; administration & dosage ; deficiency ; Randomized Controlled Trials as Topic ; Sodium Chloride, Dietary ; administration & dosage