Homing and engraftment of transplanted hematopoietic stem cells (HSCs) can directly influence the effect of the transplantation.Exploration on its spatial distribution,location and interaction with the bone marrow (BM) microenvironment is great significance.Since the BM cavity is closed and surrounded by thick compact bone,it makes a colossal challenge to track the transplanted HSCs in vivo directly.Recently,researchers used different innovative methods to observe the spatial distribution and interaction with the BM microenvironment of the transplanted HSCs.The present review summarized the progress in the HSCs transplantation.

OBJECTIVE:To establish a microbial limit test method for povidone iodine solution.METHODS:Validation on methodology of the microbial limit test of povidone iodine solution was performed using plating method(Ⅰ),culture agent dilution method(Ⅱ),membrane-filter procedure method(Ⅲ)and sodium thiosulfate neutralization in combination with membrane-filter procedure method(Ⅳ).RESULTS:The recovery rates of all of the test organisms in method Ⅰ and method Ⅱ approached zero,less than 70% in method Ⅲ but above 85% in method Ⅳ.The growth of the control bacteria was abnormal in method Ⅱand method Ⅲ,but normal in method Ⅳ.CONCLUSION:It is advisable to adopt the method Ⅳ for microbial limit test of povidone iodine solution.

Objective To investigate the dosimetric difference of organ at risk (OAR) for planning and actual estimated during intensity-modulated radiotherapy (IMRT) for patients with nasopharyngeal carcinoma.Methods Thirteen patients were enrolled to accept full course of IMRT.CT scans were acquired in the 10th,20th,and 30th fractions during radiotherapy,respectively.OAR,including brain stem,spinal cord,parotid gland and submandibular gland,were delineated on repeated CT scans.The volume change of OAR were investigated.After that,the plans were copied to the new CT image to calculate the escalated average dose of OAR during radiotherapy (Actual estimated receiving dose minus planning dose).Results The change trend of volume was decreasing gradually for parotid gland and submandibular gland during the 10th,20th,and 30th times radiotherapy (all P =0.000).The maximum dose (Dmax) of brain stem and spinal cord and the 50％ volume receiving dose (D50) of parotid gland increased significantly in the 10th,20th,and 30th times during radiotherapy,respectively.The escalated average dose were 3.76 and 3.68 Gy for Dmax of brain stem and spinal cord (P =0.000,0.000),5.11 and 3.54 Gy for D50 of left and right parotid (P =0.001,0.023),and 0.49 and 0.75 Gy for D50 of left and right submandibular gland (P =0.220,0.230),respectively.Conclusions The volume of parotid gland and submandibular gland significantly decreased after radiotherapy The actual receiving dose of brain stem,spinal cord,and parotid gland increased significantly during radiotherapy.However,there was no significant change for the actual receiving dose of submandibular gland.

Objective To investigate the pregnancy opportunity and outcome of patients with sysmetic lupus erythematosus (SLE).Methods We carried out a retrospective analysis of the clinical information of patients who suffered from SLE complicated with pregnancy and were hospitalized to People's Hospital of Peking University from December of 1992 to February of 2012.Chi-square test were used for statistical analysis.Results Forty-nine cases of patients with SLE complicated with pregnancy had 52 pregnancies in total.In 27 cases of planned pregnancies,24 cases(89％ )resulted in live births and 5 cases( 18％ ) had flares during pregnancy.Of the 24 live births,3 cases( 12％)were premature deliveries and 4 cases(17％) had low birth weight infants.In 25 cases of unplanned pregnancies,12 cases (48％) resulted in live births and 20 cases (80％) had flares during pregnancy.Of the 12 live births,6 cases(50％ ) were premature deliveries and 6 cases (50％) were low birth weight infants.The patients in the planned pregnancy group tended to have flares during pregnancy more frequently than those in the unplanned group (P＜0.01),the former were more likely to have live births than the latter (P＜0.01) and were less likely to have premature delivery (P＜0.05).Conclusion Patients with SLE should have planned pregnancy and need collaborative supervision of both rheumatology and immunology department and obstetric department to improve live birth rate,decrease premature delivery and the activity of SLE during pregnancy.

Objective To compare the difference of the microleakage repaired by direct method and indirect method of the funnel shaped root canal in the anterior teeth. Methods A total of 22 middle teeth at the similar size were collected, prepared into funnel root canal after finishing the root filling. The teeth were divided into A and B groups randomly, and there were 11 test pieces in each group. The root canal was repaired by direct method in group A and indirect method in group B. After 500 thermal-cold cycling and 240 000 dynamic cyclic loading,one tooth was selected in each group randomly. The microstructure were observed by scanning electron microscope (SEM). One piece of each group was randomly selected and the image of the core and the dentin was scanned by electron microscope. The remaining 20 pieces were dyed by India ink, dealt with transparent, compared and observed under the microscope. The degree of microleakage was recorded and analyzed in two groups. Results Under electron microscope, a gap can be observed in the bonding interface of group A. The gap was significantly bigger than that of group B. The leakage was significantly serious in group A than that in group B (P<0.05). Conclusion The level of microleakage of anterior teeth with flared canals, which is restored by fiber post core with the indirect method, is significantly better than that with the direct method. The indirect method has a good edge seal action and is more suitable for clinical application.

A novel silica monolithic stationary phase functionalized with butylaminopropyl ligands for capillary electrochromatography(CEC) has been presented. The monolithic capillary columns were prepared by a sol-gel) process and subsequent a chemical modification. The amino groups on the surface of the stationary phase are meant to generate a substantial anodic electroosmotic flow (EOF). The butyl and propyl groups provide) hydrophobic properties. To evaluate the column performance, effects of buffer pH and organic modifier content on the EOF and electrochromatographic retention behavior of alkylbenzenes, organic acids and anilines were investigated. The monolithic stationary phase exhibited reversed phase (RP) chromatographic behavior toward neutral solutes. The model organic acid anion solutes were separated by the mixed mode mechanism, which comprised RP interaction, weak anion-exchange, and electrophoresis. Basic compounds such as anilines) were well separated on the butylaminopropyl silica monolithic column without peak tailing.

Basic knowledge of forensic science is theoretical and abstract,therefore,confir-matory experiment teaching is often adopted in the experiment teaching. International education has become an important topic in medical colleges and universities. Forensic medicine is a compulsory subject for medical international students. This article discussed the exploration and practice in teach-ing forensic medicine for international students at Wenzhou Medical University,which included faculty constructing and training,encouraging whole English teaching by young teachers,applying heuristic interactive teaching and case teaching,establishing strict attendance and appraisal system and con-ducting comprehensive evaluation on medical teaching quality and teaching management.

Objective To assess the diagnostic predictive value of Wells score and modified Geneva score for acute pulmonary embolism by prospective case series and to explore a more suitable scoring system for Chinese population.Methods All the patients suspected of pulmonary embolism (PE) and received CT pulmonary angiography (CTPA) were enrolled consecutively in Fuxing Hospital,Capital Medical University,China,from June 2009 to August 2011.Before CTPA test or on condition that test results were unknown,clinical scoring was assessed prospectively by the Wells score and the modified Geneva score.The probability of PE in each patient was assessed and the patients were divided into low,moderate and high probability groups according to the clinical scores.The result of CTPA was used as the diagnostic gold standard for PE.Diagnostic accuracy in each group was analyzed.The predictive accuracy of both scores was compared by AUCROC curve.Results A total of 139 patients met our enrollment criteria and 117 eligible patients entered our study at last.PE was diagnosed in 47 patients by CTPA with an overall prevalence of 40.2％.Prevalence of PE in the low,moderate and high pretest probability groups assessed by the Wells score and by the simplified modified Geneva score were 7.1％ (3/42),42.9％ (21/49),88.5％ (23/26)and 10.0％ (3/30),48.1％ (37/77),7/10,respectively.AUCROC curves for the Wells score and the simplified modified Geneva score were 0.872 ( 95％ CI 0.810-0.933 ) and 0.734 ( 95％ CI 0.643-0.825 )respectively,with a significant difference ( P =0.005 ).Conclusion The Wells score is more accurate for clinical predicting acute PE than the modified Geneva score.

ObjectiveTo analyze the clinical distribution and antimicrobial resistance profile of Serratia marcescens(S. marcescens), and to provide the scientific evidence supporting clinical diagnosis and treatment.MethodsThe antimicrobial susceptibility test was performed in 104 strains of S. marcescens by agar dilution method. The results were judged according to the criteria recommended by Clinical and Laboratory Standards Institute (CLSI) 2010.The data were analyzed by chi square test. Results The majority of S. marcescens were isolated from sputum specimens,accounting for 59.6％ (62/104). The bacteria were most frequently isolated from department of respiratory (33.7％,35/104),followed by intensive care unit (23.1％,24/104),department of gerontology (16.3％, 17/104). The results of antimicrobial susceptibility test showed that the resistance rates of S.marcescens against ampicillin,gentamicin and cephazolin were high,which were 90.4％,86.5％ and 79.8％,respectively; those against the 3rd generation of cephalosporins were 24.0％-43.3％. No imipenem and meropenem resistant strains were identified. Compared with cefoxitin-resistant strains,the resistance rates of non-cefoxitin resistant strains against piperacillin (82.9％ vs 28.6％),ceftazidime (63.4％ vs 9.5％),aztreonam (68.3％ vs 9.5％),amikacin (68.3％ vs 20.6％),ciprofloxacin (48.8％ vs 19.1％) and chloramphenicol (90.3％ vs 58.7％) were all lower (all P ＜ 0.05 ). Conclusions S. marcescens is one of the most common conditional pathogenic bacteria leading to nosocomial infections,which is resistant to many kinds of antimicrobial agents.The surveillance of antimicrobial resistance in S. marcescens should be strengthened for purpose of preventing the transmission of multidrug resistant strains.