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ObjectiveTo investigate the metabolites and gene expression characteristics in fibrous roots of Dioscorea zingiberensis in response to low phosphorus stress. MethodThe severe stress group, the moderate stress group, and the normal group were set up to stimulate the low phosphorus stress experiment. The fibrous roots of D. zingiberensis were collected during initial stress. The metabolites and transcriptomic characteristics were analyzed by gas chromatography-mass spectrometry (GC-MS) derivatization and RNA-seq techniques. Through multivariate statistical analysis of metabolites treated by different methods,functional analysis of differentially expressed genes, and data mining, the metabolism markers produced in fibrous roots of D. zingiberensis under low phosphorus stress were screened out, and the metabolic pathway characteristics of different genes were analyzed. ResultA total of 116 GC-MS metabolites were detected from the fibrous roots of D. zingiberensis. The metabolic characteristics of fibrous roots of D. zingiberensis under different low phosphorus treatments were obviously different. Orthogonal partial least squares discriminant analysis(OPLS-DA) model was used to screen six differential metabolites represented by sugars and alcohols from metabolites of fibrous roots treated with different methods,and these components were presumedly metabolism markers of fibrous roots of D. zingiberensis in response to low phosphorus stress. The differential genes screened out from the severe stress group and the normal group were mainly enriched in peroxidase pathway,phosphate and hypophosphate metabolism pathway,while the differential genes screened out from the severe stress group and the moderate stress group were mainly enriched in glutathione metabolism pathway and phosphopentose pathway. A total of 177 differential genes in response to low phosphorus stress were screened out from fibrous roots, involving many pathways such as terpenoid skeleton and inositol biosynthesis,which was consistent with the fact that the metabolic differential components in fibrous roots in response to low phosphorus stress were mainly saccharides and inositol. ConclusionThe metabolites and gene expression in fibrous roots of D. zingiberensis responded to low phosphorus stress,and the differential metabolites were closely related to differentially expressed genes. This study is expected to provide a theoretical basis for the research on the molecular mechanism of D. zingiberensis in response to low phosphorus stress.
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Objective:To further improve the quality of doctoral dissertations in clinical medicine and stomatology.Methods:Taking the 1 122 experts' comments on the 2016-2018 clinical/stomatological doctoral dissertations of a university, the paper made a statistical analysis from such aspects as the source of topic selection, the type of topic selection, the literature review, paper innovation, writing standards, etc. SPSS 20.0 was used for statistical analysis.Results:The results showed that 61.0% (614/1006) dissertations were selected from applied research and 30% (302/1006) from non project research; 83.9% (941/1122) dissertations were evaluated as good and excellent, and the first three items with poor evaluation were: innovation (3.3%, 37/1122), content (2.2%, 25/1122) and writing standard (0.9%, 10/1122).Conclusion:It is suggested that the school and tutors should make clear the training orientation of clinical/stomatological doctoral graduate students, strengthen the training of their scientific research ability and thesis writing ability, and pay attention to clinical practice training without reducing their academic requirements.
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OBJECTIVE: To establish a method for rapid determination of total phenylethanoid glycosides and total iridoid glycosides in the root of Rehmannia glutinosa. METHODS: The contents of total phenylethanoid glycosides and total iridoid glycosides in medicinal material samples were determined by UV spectrophotometry. Quantitative model of total phenylethanoid glycosides and total iridoid glycosides in medicinal samples was established by NIRS-PLS method. The optimal pretreatment spectra were multivariate scattering correction combined with first derivative method, standard normalization combined with first derivative method. The optimum spectral ranged from 6 703.35-11 065.54 cm-1 and 3 999.63-9 102.36 cm-1. The optimum principal factor number were 10 and 7. RESULTS: The content determination of total phenylethanoid glycosides and total iridoid glycosides in medicinal material samples was proved to meet the requirements by methodological experience. The internal cross validation determination coefficients of total phenylethanoid glycosides and total iridoid glycosides were 0.998 2 and 0.980 9. The correction of root mean square error was 0.032 7 and 0.186 0. The root mean square error of prediction were 0.035 5 and 0.035 1. The root mean square error of cross validation were 0.256 9 and 0.574 3. The predicted values of total phenylethanol glycosides and total iridoid glycosides were 0.268%-1.636% and 3.424%-6.978%, respectively; the determination value of them were 0.299%-1.629% and 3.431%-6.952%, respectively; the absolute deviations were -0.042%-0.067% and -0.111%-0.088%, respectively;the relative deviations were -0.819%-0.076%、-2.257%-1.672%, respectively;There was no statistical significance between predicted values and measured values (P>0.05). CONCLUSIONS: The method is accurate and simple. The method can be used for the rapid determination of total phenylethanoid glycosides and total iridoid glycosides in different germplasms of R. glutinosa.
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Objective To understand the current situation of research innovation ability of medical academic PhD students,combining with the comprehensive reform of education of the university's doctoral postgraduate students,and put forward suggestions for improving the scientific research innovation ability of medical academic PhD students.Methods Analyzing the evaluation results of academic doctoral dissertation of the medical department in 2017 and conducting questionnaire survey among graduates with SO JMUP,a professional online questionnaire platform,are the main methods.Results Among all the indexes of medical academic doctoral dissertation,innovation achievement was evaluated lowest,and only 34.9 % of the evaluation experts considered it as excellent.In terms of innovation results and research ability,the eight-year PhD is better than the five-year and three-year PhD significantly.The mentor's guidance and education are believed to be the primary factors to enhance their interest in scientific research by graduates.Conclusions The ability of medical academic PhD students needs to be strengthened.It is suggested to build a platform for cultivating top-notch innovative talents,and enhance the academic vitality of the tutor to ensure the research training of graduates as well as provide an international exchange platform to broaden the academic horizon of the graduates.
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Methyl (S)-4-(6-amino-9H-purin-9-yl)-2-hydroxybutanoate (DZ2002) is a potent reversible inhibitor of S-adenosyl-L-homocysteine hydrolase (SAHH). Due to its ester structure, DZ2002 is rapidly hydrolyzed in rat blood to 4-(6-amino-9H-purin-9-yl)-2-hydroxybutyric acid (DZA) during and after blood sampling from rats; this hampers accurate determination of the circulating DZ2002 and its acid metabolite DZA in rats. To this end, a method for determining the blood concentrations of DZ2002 and DZA in rats was developed by using methanol to immediately deactivate blood carboxylesterases during sampling. The newly developed bioanalytical assay possessed favorable accuracy and precision with lower limit of quantification of 31 nM for DZ2002 and DZA. This validated assay was applied to a rat pharmacokinetic study of DZ2002. After oral administration, DZ2002 was found to be extensively converted into DZA. The level of systemic exposure to DZ2002 was significantly lower than that of DZA. The apparent oral bioavailability of DZ2002 was 90%–159%. The mean terminal half-lives of DZ2002 and DZA were 0.3–0.9 and 1.3–5.1 h, respectively. The sample preparation method illustrated here may be adopted for de-termination of other circulating ester drugs and their acid metabolites in rodents.
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OBJECTIVE:To establish the HPLC fingerprint of Zhibai dihuang pills(concentrated pills),and to evaluate its quality. METHODS:The determination was performed on Dikma Diamonsil C18column with mobile phase consisted of 0.1%acetic acid solution-methanol(gradient elution)at the flow rate of 1.0 mL/min. The detection wavelength was set at 260 nm,and column temperature was 30 ℃. The sample size was 10 μL. Using paeonol as reference,HPLC chromatograms of samples from A, B,C manufacturers within validity period and samples from manufacturer A within validity period and out of validity period were drawn. The similarity of HPLC chromatogram for samples from A,B and C manufacturers and samples from A manufacturer within validity period and out of validity period was evaluated by TCM Chromatogram Fingerprint Similarity Evaluation System (2004 A). Common peaks of HPLC chromatogram for 3 manufacturers sample within validity period were confirmed. RESULTS:There were 24,29 and 32 common peaks in HPLC chromatograms for each 10 batches of samples from manufacturer A,B and C within validity period,respectively. The similarity of corresponding HPLC chromatograms of samples from manufacturer A,B and C compared with control HPLC chromatography were all higher than 0.94 with good agreement. HPLC chromatograms of sample from A manufacturer within validity period had good agreement with that from A manufacturer out of validity period. CONCLUSIONS:Established HPLC fingerprint analysis method can represent the quality of Zhibai dihuang pills (concentrated pills),but cannot effectively identify the expired samples.
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With the opportunity of the comprehensive reform of professional postgraduate education,Peking University design the professional postgraduate education structure to social need,explore the training mode of DrPH,PharmD,MMT with international standards;To implement the spirit of medical cooperation,promote the organic linking of training of MD and specialist.
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Objective To explore and establish a kind of dissertation evaluation system which can fully reflects the characteristics of academic medical doctoral training.Methods 41 medical doctoral dissertation evaluation systems and related literatures were collected,to get the current situation of this dissertation evaluation system in our country and find the key points of various evaluation systems.A questionnaire survey was conducted among 350 doctoral supervisors coming from 6 universities so as to define the framework and connotation of evaluation indicators.Using the Delphi expert consultation method,the connotation of evaluation indicators and composition as well as the weight of various indicators was improved.Results The doctoral supervisors who participated in the research considered that building the dissertation evaluation system should follow the principle of science,innovation and fairness,and the evaluation frame-work should have secondary index and evaluation elements.The evaluation contents concluded choosing topic,literature review,basic theory and professional knowledge,paper writing,innovation,research ability and academic morals and so on.And on the basis of this,the paper explored and developed a more scientific and comparative dissertation quality evaluation system with medical specialty.Conclusion The cultivation units should take the educational goal of evaluation target and the requirements of awarding degree into consideration,seeking opinions fully to the first-line supervisors and combing quantitative and qualitative evaluation effectively with scientific and operable principles when specifying evaluation system.
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Objective To assess the efficacy and safety of peginterferon ( PegIFN) α-2b in treatment of HBeAg-positive chronic hepatitis B ( CHB).Methods Thirty two patients with HBeAg-positive CHB admitted in Peking University Shenzhen Hospital during November 2013 and January 2014 were recruited in the study.Patients were center randomly assigned into two groups : 22 patients in test group were treated with 180 μg PegIFN α-2b, 1 /w for 48 wk; 10 patients in control group were treated with 180 μg PegIFN α-2a (Pegasys), 1 /w for 48wk.All patients were followed up for 24wk after treatment.Virology markers, HBV DNA levels and liver functions were monitored regularly , and adverse events were observed . Fisher’s exact test was used to compare the efficacy and safety between two groups .Results There were no statistically significant differences between the control group and test group in ALT normalization rates , HBV DNA negative rates and HBeAg serological conversion rates both at the end of treatment and at the end of 24-wk follow-up (all P >0.05).Both groups had similar adverse effect incidence rates (P >0.05), but retina disease occurred in 7 cases of test group, which was not observed in control group .Conclusion Compared with PegIFN α-2a, PegIFN α-2b has similar efficacy and safety for patients with HBeAg -positive CHB.
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This study was aimed to establish a rapid detection method for timosaponin BⅡ in Anemarrhenae Rhizoma in order to determine its concentration quickly,conveniently and efficiently.The concentration of timosaponin BⅡ in A.Rhizomadetected by HPLC in the Chinese Pharmacopeia was used as the actual measured value.The near-infrared spectroscopy (NIRS) was used to collect the spectrogram of A.Rhizomasamples.The partial least squares (PLS) of TQ Analyst 8.0 were used in the data analysis.Through the pretreatment,wavelength range and principal component number selection,the actual measured value and NIRS information were associated for the establishment of the optimal quantitative analysis model of timosaponin BⅡ.The results showed that the correlation coefficients (R2),root-mean-square error of calibration (RMSEC),root-mean-square error of prediction (RMSEP),root-mean-square error of cross-validation (RMSECV) and the performance index (PI) of the established model were 0.975 15,0.094 2,0.080 0,0.369 20,and 91.0,respectively.It was concluded that the established quantitative analysis model by NIRS with HPLC was able to determine the concentration of timosaponin BⅡ in A.Rhizomaquickly and accurately.
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Using cDNA from Rehmannia glutinosa leaf as template, a 972 bp fragment of expansin gene which containing a 762 bp ORF that encoded 253 amino acids, was cloned, named RgEXPA10, which GenBank accession number for this gene is KF011918. A 1 207 bp genomic sequence of RgEXPA10 was amplified by PCR with leaf DNA as template, sequencing analysis revealed that three exons and two introns in RgEXPA10 genomic sequence, and which GenBank accession number is KF011919. Molecular and bioinformatic analyses indicated that RgEXPA10 protein have DPBB_1 and Pollen_allerg_1 domain, also including a 26 aa nuclear localization signal and a 19 aa transmembrane region. Phylogenetic analysis revealed that RgEXPA10 showed the highest homology with AtEXPA8 among the 26 α-expansins in Arabidopsis thaliana. However, the RgEXPA10 indicated the highest homology with the expansin from Solanum lycopersicum among 22 plant species. Expression patterns using qRT-PCR analysis showed that RgEXPA10 mainly expressed in unfolded leaf, followed by the tuberous root at stage of expanding period, and rarely expressed in senescing leaf. And RgEXPA10 showed higher expression level in tuberous root at 60 and 90 days after emergence. The transcription level of RgEXPA10 significantly reduced under all the three stresses including continuous cropping conditions, salinity and waterlogging. This study will lay foundations for molecular function in development and regulation of different stresses for R. glutinosa.
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This paper discusses the effectiveness of tutor-postgraduate communication in terms of frequency,approach,activeness and content by analyzing the questionnaire filled by the postgraduate students who graduate in 2013 in Peking University Health Science Center.3 suggestions were put forward to enhance the efficiency and quality of tutor-postgraduate communication,including guideline from tutors,active involvement of graduates and facilitation of Scientific research management.
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Objective To discuss the impact of nursing intervention on self- care ability and health behavior of cancer patients with indwelling PICC in order to improve their life. Methods 218 cases of cancer patients with PICC catheter were randomly divided into the intervention group (107 patients)and the control group (111 patients),the control group were treated with conventional care, the intervention group was treated with targeted cognitive intervention by the PICC nurse specialists on the basis of conventional care. Interventions included improving health knowledge, self-concept, self-care responsibility and self-care skills in four areas, the intervention lasted 3 months. A questionnaire survey was conducted before and after intervention. Self-care skills and health behavior levels were compared between the two groups. Results Self-care skills and health behavior levels of the intervention group were significantly higher thanthose of the control group after intervention. Conclusions Targeted interventions can effectively improve the self-care capacity of outpatient oncology patients with PICC catheter and improve their health behaviors.
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Objective To analyze the reasons of abnormal extubation for the chemotherapy patients with PICC,and put forward preventive measures. Methods A retrospective investigation was carried out about the reasons for abnormal extubation in 583 chemotherapy patients with PICC in our hospital from December 2007 to September 2009. Results There were 63 cases of abnormal extubation in 583 patients, accounted for 10.8% of the total number. The reasons of abnormal extubation included: catheter-related infection, misplacement,prolapse, dilapidation and fracture, catheter occlusion,thrombosis and abandoning treatment. Conclusions Complications caused by PICC are the main reasons for abnormal extubation. Important care measures to prevent and deal with kinds of complications timely can reduce the incidence of abnormal extubation.
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3-ketosteroid-9alpha-hydroxylase (KSH), a key enzyme in the microbial steroid degradation, is highly valuable for the production of some steroid drugs. Degenerate primers were designed by comparing the ksh from Rhodococcus erythropolis SQ1 and its homologous sequences in the reported genome of Mycobacteria. Subsequently, a gene fragment of KSH was cloned from Mycobacterium sp. NwIB-01, a sterol-transforming bacterium isolated from soil in our lab. According to the conservative sequence, the full-length 1188 bp gene encoding ksh (designated as M.S.-ksh) was obtained by chromosome walking, which showed 85% identity with the ksh of M. smegmatis mc(2)155. The heterologous expression of KSH was achieved in Escherichia coli BL21(DE3) using the pET-32a-c(+) vector system. The expressed KSH protein was mostly in soluble form after IPTG induction at 30 degreesC and accounted for more than 30% of total bacterial proteins according to SDS-PAGE electrophoresis. The molecular mass of KSH was about 45 kD, which was exactly the size predicted. After Ni2+ affinity chromatography, the purity of the target protein was more than 90%. Our work will definitely contribute to the industrial production of some steroid drugs by developing KSH genetically engineered bacteria.
Sujets)
Protéines bactériennes , Génétique , Séquence nucléotidique , Clonage moléculaire , Escherichia coli , Génétique , Métabolisme , Mixed function oxygenases , Génétique , Données de séquences moléculaires , Mycobacterium , Ingénierie des protéines , Méthodes , Microbiologie du sol , StéroïdesRésumé
Objective To understand the needs of health education of TCM health preservation and re-habilitation in community patients with chronic disease in order to instruct nurses to carry out health education pur-posively. Methods A questionnaire survey was carried out in 320 patients with coronary heart disease, hyper-tension, chronic liver disease, diabetes mellitus, chronic obstructive pulmonary disease(COPD) and other chronic diseases. The investigation contents included cognition of TCM health preservation and rehabilitation, knowledge needs and demand patterns and the results underwent analysis. Results In 320 patients, 11% of patients understood the TCM health preservation and rehabilitation-related knowledge, 43% understood part of it, 46% knew nothing about it. All patients showed different degree of needs for TCM .health preservatiou and reha-bilitatiou and different demand patterns,and the total demand for various educational content was above 90%. Needs for disease prevention, health seasons, TCM dietetic therapy occupied the first three. Health care workers o-ne- to-one education was the most popular form of health education. 75% of the patients hoped that the family members were given health education at the same free. Conclusions Patients with chronic disease possess de-ficient but greater needs for knowledge about TCM health preservation and rehabilitalion. The awareness and ca-pability of serf-care, health preservation and rehabilitation and prevention-tirst should be improved.
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Objective To discuss effective nursing measures to reduce incidence rate of anxiety and depression caused by α-intefferen treatment,and to enable the successful completion of interferon treatment for hepatitis B patients. Methods Hepatitis B patients(220 cases) receiving α-interferon treatment were randomly divided into the intervention group(115 cases) and the control group(105 cases).The control group adopted conventional nursing,while in the intervention group,comprehensive intervention measures such as close observation,psychological intervention,symptomatic treatment intervention were used.Zung self-rating depression scale (SDS) was used to compare the incidence rate of anxiety and depression.The completion of treatment was also compared between the two groups. Results After 3,6 and 12 months of treatment incidence rate of anxiety and depression in the intervention group was significantly lower than that of the control group (P<0.05).There were 112 cases completed treatment in the intervention group,which were higher than those of the control group,72 cases (P<0.01). Conclusions Nursing intervention measures such as close observation,psychological intervention,symptomatic treatment can reduce incidence rate of anxiety and depression caused by a-interferon treatment.