The information entropy, H = - Pk log Pk, has been proved in this paper to be always positive and invariant for a linear coordinate transformation, so that it can be used as a measuring index. On the contrary, the integral term of the information entropy, H(x) = -f(x) log f(x) dx, is not always positive and invariant for a linear coordinate transformation. Therefore, H(x) can not be used as a measuring index. An example of a probability density function for response of nerve to electric current with different intensities is given to confirm above conclusions.

AlM:To investigate the effect of teaching mode of problem- based learning ( PBL ) in the teaching of medical students' clinical ophthalmology.
METHODS: Five classes ( total 148 students ) were randomly selected as experimental group, using PBL method, at the same time another 5 classes ( total 151 students) were also randomly selected as control group, using lecture-based learning ( LBL) mode in 2010 grade. The scores of the experimental group were compared with control at the end of term. ln addition, students and teachers were respectively interviewed using self -administered questionnaire to obtain their evaluation for PBL practice.
RESULTS:The mean scores of PBL group (78. 35±7. 63) were significantly higher than control group (71. 68±6. 37) (P<0. 001). Most of students thought that their ability of referring, synthesizing and analyzing information was enhanced by PBL, and their skills both in written and oral were also improved. PBL made it easier to understand the contexts of course. lt was the best way to improve the effect of teaching in ophthalmology based on the increase of quality in novitiate that gives more chance to students of contacting with practice, developing the ability of clinical thinking and verifying the theory in clinical novitiate. Lots of teachers considered that the classroom atmosphere was more active, students were becoming more and more proactive on their classes and the relationship between students and teachers were more harmonious when PBL was used.
CONCLUSlON:Using PBL teaching mode can highly improve the teaching effectiveness of clinical epidemiology, which is worth popularizing.

Objective To find out the risk factors of postoperative low cardiac output syndrome(LCOS) of patients undergoing cardiac valvular surgery in ICU in order to provide basic for prevention and control measures.Methods Ninety-six valve replacement patients with valvular heart disease were enrolled as our subjects and they were hospitalized in ICU of the First People's hospital of Yichang from Jan.2008 to May.2013.The patients postoperative LCOS (Dopamine ＞ 10 μg/(kg · min)) were served as observation group (n =41),and the other were control groups(n =55).All data of the patients were recorded.Non-conditions Logistic regressions analysis were adopted to analyze the independent risk factors which resulted in LCOS undergoing cardiac valvular surgery.Results Of 96 patients undergoing cardiac vavular surgery,41cases (42.7％) had postoperative LCOS.Single factor analysis showed that hepatomegaly (P =0.007),course of diseases ≥ 15 years (P =0.042),cardiopulmonary bypass ≥ 120 min (x2 =3.937,P =0.047),pre-operative cardiac function ≥ Ⅲ degree (P =0.003) were the independent risk factors of postoperative LCOS undergoing cardiac valvular surgery.The Logistic multi factor regression analysis showed that the independent risk factors of postoperative LCOS undergoing cardiac valvular surgery included course of diseases ≥ 15 years (OR =2.825,95％ CI =(1.015-7.861)),Pre-operative cardiac function ≥ Ⅲ degree (OR =7.306,95％ CI =(2.050-26.035),P=0.002).Conclusion Course of diseases ≥15 years and Pre-operative cardiac function≥ Ⅲ-Ⅳ degree are the independent risk factors of LCOS undergoing cardiac valvular surgery.

The relationship between tyrosine phosphorylation (TP) and protein expression of insulin receptor (InsR) and insulin resistance (IR) in patients with gestational diabetes mellitus (GDM) was investigated. The InsR expression and TP in skeleton muscle tissue were determined by Western blotting and immunoprecipitation in women with GDM (GDM group, n=22), normal pregnant women (normal pregnancy group, n=22) and normal non-pregnant women (normal non-pregnant group, n=13). Fasting plasma glucose (FPG) and fasting insulin (FINS) were measured by oxidase assay and immunoradioassay. The results showed that the levels of FPG (5.61±0.78 mmol/L), FINS (15.42±5.13 mU/L) and Homeostasis model assessment-IR (HOMA-IR) (1.21±0.52) in GDM group were significantly higher than those in normal pregnancy group (4.43±0.46 mmol/L, 10.56±3.07 mU/L and 0.80±0.31 respectively) (P<0.01). The levels of FINS and HOMA-IR in normal pregnancy group were significantly higher than those in normal non-pregnant group (7.56±2.31 mU/L and 0.47±0.26 respectively) (P<0.01). There was no significant difference in the InsR expression level among the three groups (P>0.05). TP of InsR with insulin stimulation was significantly decreased in GDM group (0.20±0.05) as compared with normal pregnancy group (0.26±0.06) (P<0.01). TP of InsR with insulin stimulation in normal pregnancy group was lower than that in normal non-pregnant group (0.31±0.06) (P<0.01). TP of InsR with insulin stimulation was negatively related with HOMA-IR in GDM group (r=-0.525, P<0.01). There was no correlation between the protein expression of InsR and HOMA-IR in GDM group (r=-0.236, P>0.05). It was suggested that there is no significant correlation between the protein expression of InsR in skeletal muscle and IR in GDM, but changes in TP of InsR are associated with IR in GDM.

OBJECTIVETo analyze the chemical constituents of supercritical carbon dioxide extraction products from Cnidium monieri.

METHODFour-factor and three-level orthogonal experimental design was used to optimize the SFE conditions as guided by the content of total coumarins in the extract. The chemical constituents were separated and identified by recrystalization.

RESULTOptimum extraction process was established: 25 MPa as extraction pressure, 50 degrees C as extraction temperature, 6.5 MPa as separation pressure and 60 degrees C as separation temperature.

CONCLUSIONChanges in extraction pressure, temperature, time, pulverized degree and separation pressure affect the extracting results remarkably. The two kinds of chemical constituents were separated by recrystallization from C. monieri and identified by the methods of UV, IR, MS, NMR.

Chromatography, Supercritical Fluid ; Cnidium ; chemistry ; Coumarins ; chemistry ; isolation & purification ; Fruit ; chemistry ; Furocoumarins ; chemistry ; isolation & purification ; Plants, Medicinal ; chemistry

Objective To investigate the relationship between genetic single-nucleotide polymorphisms of ligase Ⅳ (LIG4) and heat shock protein B1 (HSPB1) and prognosis in nasopharyngeal carcinomas.Methods DNAs were extracted by phenol-chlorofrom method from peripheral blood samples of 168 nasopharyngeal carcinoma patients.Genetic single-nucleotide polymorphisms were divided by Taqman realtime polymerase chain reaction (PCR).All statistical analyses were performed with statistical product and service solutions v13.0.A p-value of less than 0.05 was confirmed as statistical significance.Single-factor and multiple-factor logistic analyses were used to calculate odds ratio (OR) and 95％ confidence interval (CI).Long-rank test and COX were also used.Results No relationship was found between the recurrence,metastasis and overall survival of nasopharyngeal carcinoma and genetic single-nucleotide polymorphisms of LIG4 and HSPB1 with single-factor and multiple-factor logistic analyses.Conclusions LIG4 rs1805388 and HSPB1 rs2868371 had no relationship with prognosis of nasopharyngeal carcinomas.

Objective To explore the clinical characteristics,management and pregnancy outcome in patients with ovarian tumor and ovarian tumor like condition complicated with pregnancy.Methods The clinical data of 248 patients with ovarian tumor and ovarian tumor like condition eomplicated with pregnancy who treated,operated and pathology conducted from January 2003 to December 2009 was analyzed retrospectively.Results Among of 248 patients,8 patients were found by pelrioscopy,184 patients were found by sonography.The rate of ovarian tumor and ovarian tumor like condition during pregnancy was 0.49％ (248/50 652),about 52.82％(131/248)were diagnosed as benign tumor,most of them were ovarian mature teratoma(22.18％,55/248).About 45.56％(113/248)were diagnosed as ovarian tumor like condition,most of them were ovarian chocolatecyst(23.79％,59/248).Four patients(1.61％,4/248)were ovarian malignant tumor.Two hundred and sixteen received operation,term birth was in 164 patients,premature birth was in 19 patients,miscarriage was in 33 patients.Conclusions Pelvioscopy and sonogaraphy are principally important in the diagnosis and detection of ovarian tumor during pregnancy.Pregnancy complicated with ovarian tumor or ovarian tumor like condition should be treated by tumor resection.Suitable surgery intervention during second trimester is safe.

Objective To provide supporting evidence to prevention and controlling of caries in preschool children in Huangpu District(Eastern Part), by studying the influence of their habits at home on the prevalence of caries. Methods The oral health of preschool children in Huangpu District was examined, and their habits at home were recorded through survey questionnaire, including sugary diet, tooth brushing, parents′ attitude for oral health. Results Sugary diet could affect the prevalence of caries.There was no association between dental caries and times of tooth brushing.Parents′ attitude for oral health is the risk factor for the children′s caries. Conclusion Because of the higher prevalence of caries in the children in our district, effective measures should be taken.In addition, policy should consider how to ensure that children with high-risk dental caries receive adequate prevention and early care.

OBJECTIVETo investigate the distribution character of the mutations of 6-pyruvoyl tetrahydropterin synthase (PTPS) gene and to provide effective basis for gene diagnosis of tetrahydrobiopterin deficiency (BH4D) in children with hyperphenylalaninemia.

METHODSDirect sequencing was performed for screening the PTPS gene mutations in 5 patients with clinically suspected BH4D and their parents. The nature of the novel mutations were deduced by the sequences alignment and the structural analysis of mutant protein. Artificial construct restriction site was used to detect the novel mutation in the control samples. The dates of urinary pterin analysis and BH4 loading test were retrospectively analyzed after gene analysis.

RESULTSFour PTPS gene mutations (N52S, P87S, D96N, and L127F) were detected in our study. The genotypes of four PTPS deficiency patients were identified as N52S/L127F, P87S/D96N, N52S/D96N, and D96N/ -. As a novel mutation that has not been reported previously, the mutation L127F was not detected in 50 normal controls. This novel mutation L127F was inherited from the patient's mother, and this mutant site was highly conserved by sequences alignment and the protein structural analysis. Four of the five cases with hyperphenylalaninemia and suspicious BH4D, whose urinary biopterin percentage was lower than 2% , were diagnosed as PTPS deficiency during 5-20 months old. The remaining one case was excluded from BH4D.

CONCLUSIONSThe mutant characterization of PTPS gene was coincident with other early studies in Chinese. The novel mutation L127F was considered as a pathogenetic mutation and associated with severe clinical phenotype.

Asian Continental Ancestry Group ; genetics ; Biopterin ; analogs & derivatives ; deficiency ; genetics ; Child, Preschool ; DNA Mutational Analysis ; methods ; Humans ; Infant ; Infant, Newborn ; Mutation ; genetics ; Phenylketonurias ; genetics ; Phosphorus-Oxygen Lyases ; genetics ; Polymerase Chain Reaction

Objective:To identify proteins associated with nasopharyngeal carcinoma (NPC) metastasis,and provide scientific basis for the prevention and cure of NPC.Methods:A two-dimensional gel electrophoresis and mass spectrometry were performed to screen for differential proteins between highly metastatic 5-8F and non-metastatic 6-10B NPC cell lines.Western blot was used to confirm the differential proteins.We used siRNA to inhibit the expression of differential protein nm23-H1 to determine the association of nm23-H1 with NPC in vitro invasive ability.Immunohistochemistry and statistics were used to evaluate the correlation of nm23-H1 expression with clinicopathological features and clinical outcomes in paraffin-embedded archival tissues including 93 cases of primary NPC and 20 cases of cervical lymphonode metastatic NPC (LMNPC).Results:A total of 15 differential proteins in the 2 cell lines were identified by a proteomic approach,and 3 differential proteins were selectively confirmed.Downregulation of nm23-H1 by siRNA significantly increased the in vitro invasive ability of 6-10B.Significant nm23-H1 downregulation was observed in LMNPC compared with primary NPC.nm23-H1 downregulation in primary NPC was positively correlated with lymphonode and distant metastasis,advanced clinical stage and recurrence.Survival curves showed that patients with nm23-H1 downregulation in primary NPC had a poor prognosis.Multivariate analysis confirmed that nm23-H1 expression level in primary NPC was an independent prognostic indicator.Conclusion:nm23-H1 behaves as a metastasis suppressor in NPC,and nm23-H1 downregulation is a biomarker for poor NPC prognosis.