Based on the language problem and cultural background difference of foreign medical students,we applied Problem-based Learning in their pediatric clinic probation teaching. This method could raise students learning activeness,enhance self-teaching ability and cultivate individual clinical thinking,which is a beneficial trial in medical foreign students educational practice.

In the clinical practice of foreign students in neonatal department,the experimental group followed PBL method,while the control group took traditional "master and disciple" way. The performance records of the clinical examination and questionnaire findings are significantly different between the two groups,which confirms that PBL is a good method to be widely used in the foreign students'pediatric clinical practice.

Objective To assess the behavior of rat by suction traumatic brain injury model. Methods Suction traumatic brain injury (TBI) models were created in SD rats. Twenty-four rats were divided into two groups: suction TBI group (n=12) and sham operation group (n=12). Modified neurological severity score (mNSS) test and Morris water maze test were employed to assess the animal behavior in both groups. Results One rat was died of suction trauma. Success rate of modeling for those survivors was one hundred per cent. Cortical and subcortical contusion, hemorrhage and tissue loss were seen in paraffin section by HE staining one week after suction impact. Abnormal mNSS persisted no more than twenty-five days. Morris water maze test suggested that abnormal mean escape latency period last no more than three days. Conclusion Rat suction traumatic brain injury model is suitable for the research about neurological sensory-motor function which last relatively short period.

Objective To profile the subtypes of open reading frame 75(ORF75)of human herpesvirus 8(HHV-8)in patients with Kaposi's sarcoma,and to evaluate their relationship with clinical phenotypes and invasiveness of Kaposi's sarcoma.Methods Twenty-five paraffin-embeded tissue specimens of Kaposi's sarcoma were collected in the Department of Dermatology.People's Hospiml of Xinjiang Uygur Autonomous Region.DNA was extracted from these specimens.and nested-PCR was performed to amplify HHV-8 DNA followed bv bi-directional sequencing.Phylogenetic analysis was carried out by using the software DNASTAR,Clustal W program and PHYLIP package so as to identify the ORF75 subtyoe of HHV-8.Results HHV-8 DNA was detected in 21(84%)out of the 25 samples,and 7 cases of AIDS-associated Kaposi's sarcoma were all positive for HHV-8.Among the 21 patients carrying HHV-8 DNA,18 were positive for subtype A ORF75.3 for subtype C ORF75.The ORF75 subtypes had no significant correlation with the presence of mucosal lesions or clinical phenotypes of Kaposi's sarcoma.Conclusions The majority of patients with Kaposi's sarcoma in Xinjiang are infected with HHV-8 of ORF 75 subtype A and C.The ORF75 subtypes of HHV-8 have no correlation with the presence of mucosal lesions or clinical phenotypes of Kaposi's sarcoma.

ObjectiveTo study the single nucleotide polymorphisms(SNPs) in the ORF26 gene of HHV-8 in Kaposi's sarcoma(KS),and to assess their correlations with the clinical phenotype and mucosal invasion of KS.MethodsHHV-8 DNA was extracted with phenol-chloroform-isoamyl alcohol from paraffin-embedded tissue specimens obtained from 32 cases of KS(including 26 classic and 6 AIDS-related KS).The ORF26 gene of HHV-8 was amplified by nested-PCR followed by bidirectional sequencing.The software DNAStar and program Clustal W were used to assess the SNPs in the ORF26 gene.Statistical analysis was carried out by using the Fisher's exact probability test.ResultsHHV-8 DNA was detected in 30 of the 32 tissue specimens,and in all of the 6 AIDS-related specimens.The predominant SNPs were 981 T/C(n =12),1086 C/T(n =12) and 1139 A/C(n =12) in the ORF26 gene of the 30 strains of HHV-8.No significant difference was observed in the distribution of SNPs in ORF26 between different phenotypes of KS or between KS with and without mucosal invasion.ConclusionThe ORF26 SNPs of HHV-8 seem unrelated to the clinical phenotypes or mucosal invasion of KS.

Objective To investigate the appropriate surgical procedure for unilateral papillary thyroid microcarcinoma (PTMC).Methods Clinical data of 323 patients with unilateral PTMC in Cancer Hospital of Chinese Academy of Medical Sciences from 1999-2007 were retrospectively studied.Survival outcomes and prognostic factors were analyzed.Results After a median follow-up of 102 (range,12-188) months,the 10-year overall and disease-specific survival was 95.3％ and 98.9％.The 10-year recurrence-free survival was 85.5％.The 10-year cumulative recurrence rate of residue glands was 6.5％.Capsular invasion,pT stage and clinical stage were significant predictive factors for recurrence of residue glands (all P ＜ 0.05).Cox regression multivariate analysis showed that pT stage (HR 2.153,95％ CI 1.231-3.767,P =0.007) was independent predictive factor.Of the 311 patients treated with non-total thyroidectomy,the 10-year cumulative recurrence rate of residue glands was 6.8％ Conclusions Unilateral PTMC has a good prognosis and hemithyroidectomy (lobectomy and isthmusectomy) is an appropriate surgical pattern.Extrathyroidal extension is a significant predictor for recurrence.

Objective To investigate the chemical constituents of Wedelia trilobata.Methods The chemical constituents were separated by chromatography and their structures were determined by physico-chemical constants and spectral analyses.Results Eleven compounds were isolated and identified as grandiflorenic acid(1),1?-acetoxy-6?,9?-dihydroxy-4,10?-dimethyl-5?H,7?H,8?H-endesm-3-en-8,12-olide(2),1?-acetoxy-4?-hydroxy-6?-isobutyryloxy-9?-isovaleryloxyprostatolide(3),16?-hydroxy-ent-kauran-19-oic acid(4),(3R,4R,6R)-3,4-dihydroxy-1-menthene(5),trilobolide-6-O-isobutyrate(6),1?-acetoxy-4?,9?-dihydroxy-6?-isobutyroxyprostatolide(7),16?,17-dihydroxy-ent-kauran-19-oic acid(8),daucosterol(9),protocatechualdehyde(10),and caffeic acid(11).Conclusion All the compounds are isolated from W.trilobata for the first time except compounds 6 and 7.Compounds 2 and 3 are new sesquiterpene lactones,named as trilobolide A and 1?-acetoxy-4?-hydroxy-6?-isobutyryloxy-9?-isovaleryloxyprostatolide,respectively.

Objective To evaluate the application value of confocal laser scanning microscopy(CLSM)in the differentiation between seborrheic keratosis and Bowen′s disease. Methods CLSM was used to observe typical skin lesions in 88 patients clinically diagnosed with seborrheic keratosis and 18 patients clinically diagnosed with Bowen′s disease. Then, tissue specimens were resected from these lesions and subjected to histopathological examination. Results CLSM imaging of seborrheic keratosis lesions showed gyrus?like structures and keratin?filled inclusion cysts in the epidermis with trabecula?like extension of rete ridges in all the 88 cases, basal cells arranged in a cordike or radial pattern in 9 cases, and bright reflective structures in the basal layer and dermis in 6 cases. CLSM imaging of Bowen′s disease lesions revealed disorderly arrangement of large, irregularly shaped atypical cells in some areas in the middle and lower epidermis, and infiltration of scattered mononuclear cells in the superficial dermis. Conclusion CLSM images of seborrheic keratosis are different from those of Bowen′s disease, and CLSM may be helpful for their differential diagnosis.

Objective To analyze the clonality in Kaposi's sarcoma (KS) lesions by evaluating Xchromosome inactivation pattern in the human androgen receptor (HUMARA) gene.Methods Twenty-five paraffinembedded tissue specimens were collected from female patients with KS (n =15) or cutaneous hemangioma (n =10).DNA was extracted from these specimens,and digested with the methylation-sensitive restriction endonuclease Hpa Ⅱ.PCR was performed to amplify the HUMARA gene,and the amplicons were separated on a 10％ denaturing polyacrylamied gel and stained with ethidium bromide (EB).The loss of heterozygosity of the HUMARA gene was defined as the presence of two DNA fragments before and one fragment after the endonuclease digestion.The clonality in KS lesions was assessed based on the above results.Results Among the 15 patients with KS,13 (86.7％) were heterozygous for the HUMARA gene,of which,92.31％ (12/13) showed loss of heterozygosity of the HUMARA gene on X-chromosome,suggesting a monoclonal origin.Of the 10 patients with hemangioma,9 were heterozygous for the HUMARA gene,and only one lost heterozygosity of the HUMARA gene.The heterozygosity rate for HUMARA gene was significantly different between the patients with KS and hemangioma (P ＜ 0.01).No statistical difference was observed in the clonality status of KS between patients of different nationality,at different stages,or between patients with and without complicated human immunodeficiency virus (HIV) infection (all P ＞ 0.05).Conclusion KS is monoclonal in origin.

Objective To analyze the genotypes of human herpesvirus 8 (HHV-8) by using the polymorphisms in open reading frame(ORF) 26 gene in patients with squamous cell carcinoma (SCC)in Xinjiang Uygur Autonomous Region.MethodsDNA was extracted from paraffin-embeded tissue specimens from 41 patients with skin SCC and 46 patients with esophagus SCC,and subjected to nested-PCR for the amplification of the ORF26 gene of HHV-8 followed by bidirectional sequencing.Phylogenetic analysis was carried out to determine the genotype of HHV-8 by using the DNASTAR software,Clustal W program,and PHYLIP package.The data were analyzed by SPSS 17.0 software.ResultsHHV-8 DNA was detected in 9 (21.95％) of 41 skin SCC specimens and 10 (21.74％) of 46 esophagus SCC specimens (x2 =0.09,P＞ 0.05).As phylogenetic analysis showed,7 HHV-8 isolates from skin SCC specimens belonged to ORF26 subtype A,2 subtype C; 7 HHV-8 isolates from esophagus SCC specimens belonged to ORF26 subtype A,and 3 subtype C.Conclusions ORF26 subtype A and C are the predominate genotypes of HHV in patients with SCC in Xinjiang Uygur Autonomous Region,with the prevalence of subtype A higher than that of subtype C.The distribution of HHV subtypes seems unrelated to the location of SCC.