Users' cognition and information retrieval are faced with great challenges in ubiquitous knowledge environ-ment. The influence of cognitive factors such as personality traits, cognitive style and ability, knowledge structure and ascribed methods on users' information retrieval behaviors was thus analyzed. It was pointed out that different cognitive factors could influence the retrieval, judgment and absorption of its results,users' satisfaction and continuous use in ubiquitous knowledge environment,with suggestions put forward from the aspects of information retrieval education, information service and information users for improving the users ' knowledge system in knowledge assimilating process by working out effective retrieval strategies using the advantages of cognition.

Objective To analyze the data of influenza A(H1N1) viruses surveillance and genetic characteristics from Taian City during 2005-2008,so a scientific basis can be provided for the prevention and treatment of influenza.Methods The specimens from Influenza-Like Illness(ILI) were collected.The viruses were isolated with MDCK cell and identified with HAI and RT-PCR.The product of PCR were sequenced.Then the sequences were analyzed through biometric software.Results A total of 121 influenza strains were obtained from 615 specimens,and 4 of them were identified as A(H1N1) subtype.There were 3 strains mutated on several sites.Compared with strains isolated in 2005,there were 5 and 8 mutations in the amino acid sequences of virus strains isolated in 2007 and 2008 respectively.And there were a total of 22 amino acid mutations compared with A/Brisbane/59/2007(H1N1).Conclusions Influenza type A(H1N1) are detected in Taian City.There are several mutations in the amino acid sequences of virus strains isolated in Taian. The antigenic drift of virus strains is due to accumulation of amino acid substitutions

BACKGROUND:Stem cells have been shown to not only replace damaged cells, but also secrete trophic factors, bringing a bright future for the treatment of clinical spinal cord injury.
OBJECTIVE:To review the latest advances of bone marrow mesenchymal stem cells in animal and clinical research.
METHODS:A computer-based search of Kjmed and Wanfang databases was done for relevant articles published from April 2004 to April 2014 using the keywords of“stem cells, spinal cord injuries, embryonic stem cells, neural stem cells, mesenchymal stem cells”in English and Chinese, respectively.
RESULTS AND CONCLUSION:Total y 2 745 articles were initial y retrieved, and only 50 articles were included in result analysis. Bone marrow mesenchymal stem cells have become one of the most promising sources of stem cells in the treatment of spinal cord injury. Although the bone marrow mesenchymal stem cellin the treatment of spinal cord injury is stil in its infancy, it has certain effects on the repair of spinal cord injury. The mechanism of action of bone
marrow mesenchymal stem cells in the treatment of spinal cord injury is possibly related to the substitution effect, neurotrophic effects, suppression of the immune response and promoting axonal regeneration.

Objective To investigate the intra- and interobserver repeatability of coronary artery disease (CAD) diagnosis based on invasive coronary angiography (ICA) and CT coronary angiography (CTCA).Methods Two readers with comparable experience ( over 10 years) independently evaluated ICA results of 42 consecutive patients with a blind method. After 30 days,one of them reviewed the same patients again.Another two comparable-experience (over 10 years) readers evaluated the results of CTCA (prospectively ECG-triggering) from the same 42 patients in the same way.The inter-reader and intra-reader repeatability of ICA and CTCA were analyzed by performing Kappa test and calculating the percentage of the segments with agreement on stenotic degree.Using ICA as reference,the accuracy of CTCA in diagnosing CAD was studied by comparing the area under ROC. Results The Kappa between readers for ICA and CTCA were 0.91 and 0.81.Intra-reader Kappa were 0.92 and 0.83 respectively (x2 =509.4 and 432.5,all P ＜0.01 ).The percentage of the segments with agreement between readers on the degree of stenosis were 80.8％ (494/611) in ICA and 75.2％ (469/624) in CTCA ( x2 =2.75,P =0.10),and within the same reader,86.9％ (531/611)in ICA and 81.9％ (511/624) in CTCA(x2 =3.76,P =0.053).With≥ 50％narrowing as a CAD diagnosis criterion,the agreement rates for two readers were 96.6％ (590/611 ) in ICA and 94.4％ (589/624) in CTCA( x2 =3.36,P =0.07),and for the same reader,97.4％ (595/611) in ICA,95.4％ (595/624) in CTCA ( x2 =3.62,P =0.06).Using ICA as reference,two readers of CTCA results achieved a sensitivity and specificity of 84.9％ (530/624)and 98.1％ (612/624).The area under ROC was 0.94 (95％ CI 0.91-0.97).Conclusions Both ICA and CTCA demonstrate good repeatability in diagnosing CAD.The repeatability of ICA is superior to that of CTCA.A certain discrepancy exists in two readings from the same reader or two readers.

OBJECTIVETo assess the value of pre-gestational deafness-related mutation screening for the prevention and intervention of congenital deafness.

METHODSIn this study, 2168 couples with normal hearing were screened for common mutations associated with congenital deafness using real-time fluorescence quantitative PCR. The mutations have included GJB2 c.235delC and c.299_300delAT, SLC26A4 c.2168A>G and c.IVS7-2A>G, and mtDNA 12SrRNA c.1494C>T and c.1555A>G. For couples who have both carried heterozygous mutations of the same gene, genetic counseling and prenatal diagnosis were provided.

RESULTSAmong of the 4 336 individuals, 178 (4.06%) were found to carry a mutation. Mutation rate for c.235delC and c.299_300delAT of GJB2 gene, c.IVS7-2 A>G and c.2168 A>G of SLC26A4 gene, c.1555 A>G and c.1494 C>T of DNA 12S rRNA gene were 0.91%, 0.20%, 0.68%, 0.11%, 0.1% and 0.01%, respectively. For six couples who have both carried mutations of the same gene, all fetuses showed a normal karyotype, while DNA sequencing indicated that two fetuses have carried homozygous c.235delC mutation of the GJB2 gene, one carried a heterozygous c.235delC mutation of the GJB2 gene, one carried heterozygous mutation of GJB2 gene (c.299_300delAT), and two have carried a heterozygous mutation of c.IVS7-2A>G of the SLC26A4 gene.

CONCLUSIONPre-gestational screening for deafness gene mutation can facilitate avoidance the birth of affected children and has a great clinical value for the prevention and intervention of birth defect.

Connexins ; genetics ; Deafness ; congenital ; genetics ; prevention & control ; Female ; Humans ; Mutation ; Pregnancy ; Prenatal Diagnosis

Humans ; Leukemia, Biphenotypic, Acute ; Leukocytosis

Objective: To investigate the pathogen spectrum distribution and drug resistance of febrile neutropenic patients with hematological diseases in Shanghai. Methods: A retrospective study was conducted on the clinical isolates from the febrile neutropenic patients hospitalized in the departments of hematology in 12 general hospitals in Shanghai from January 2012 to December 2014. The drug susceptibility test was carried out by Kirby-Bauer method. WHONET 5.6 software was used to analyze pathogenic bacteria and drug susceptibility data. Results: A total of 1 260 clinical isolates were collected from the febrile neutropenic patients. Gram-positive bacteria accounted for 33.3% and Gram-negative bacteria accounted for 66.7%. Klebsiella pneumoniae (12.5%) , Stenotrophomonas maltophilia (9.5%) , Escherichia coli (9.1%) , Pseudomonas aeruginosa (8.7%) , Acinetobacter baumannii (6.6%) , Staphylococcus aureus (5.6%) and Enterococcus faecium (5.0%) were ranked in the first 7 of all pathogens. In the respiratory tract secretions specimens, non-fermented strains accounted for 56.2%. Stenotrophomonas maltophilia accounted for 15.2%. Enterobacteriaceae and coagulase-negative Staphylococci accounted for 42.3% (104/246) and 32.6% (85/246) respectively in blood samples. Enterobacteriaceae and Enterococcus bacteria accounted for 39.4% (76/193) and 28.5% (55/193) respectively in pus specimens. The detection rates of methicillin resistant Staphylococcus aureus (MRSA) and methicillin resistant coagulase negative Staphylococci (MRCNS) were 54.3% and 82.5%, respectively. Staphylococcus bacterial strain was not found to be resistant to linezolid, vancomycin and teicoplanin. The detection rate of Enterococcus vancomycin-resistant strains was 8.9%. Enterococcus was not detected resistance to oxazolidinone strains. Enterobacteriaceae bacteria were highly sensitive to carbapenems. The resistance rate of Pseudomonas aeruginosa to imipenem and meropenem was 34.1% and 15.8%, respectively. Stenotrophomonas maltophilia was more sensitive to minocycline hydrochloride, levofloxacin and sulfamethoxazole. The resistance rate of Acinetobacter baumannii only to cefoperazone-sulbactam was less than 10.0%. The antibiotic resistance rate of Klebsiella pneumoniae, Stenotrophomonas maltophilia, Pseudomonas aeruginosa and Acinetobacter baumanii to most of common antibiotics was lower than that of the CHINET surveillance. Conclusions The pathogenic strain distribution in common infection sites of febrile neutropenic patients was characterized. Bacterial resistance surveillance was better than the CHINET nationwide large sample surveillance in China.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease affecting both upper and lower motor neurons in the brain and spinal cord. One important aspect of ALS pathogenesis is superoxide dismutase 1 (SOD1) mutant-mediated mitochondrial toxicity, leading to apoptosis in neurons. This study aimed to evaluate the neural protective synergistic effects of ginsenosides Rg1 (G-Rg1) and conditioned medium (CM) on a mutational SOD1 cell model, and to explore the underlying mechanisms. We found that the contents of nerve growth factor, glial cell line-derived neurotrophic factor, and brain-derived neurotrophic factor significantly increased in CM after human umbilical cord mesenchymal stem cells (hUCMSCs) were exposed to neuron differentiation reagents for seven days. CM or G-Rg1 decreased the apoptotic rate of SOD1^G93A-NSC34 cells to a certain extent, but their combination brought about the least apoptosis, compared with CM or G-Rg1 alone. Further research showed that the anti-apoptotic protein Bcl-2 was upregulated in all the treatment groups. Proteins associated with mitochondrial apoptotic pathways, such as Bax, caspase 9 (Cas-9), and cytochrome c (Cyt c), were downregulated. Furthermore, CM or G-Rg1 also inhibited the activation of the nuclear factor-kappa B (NF-κB) signaling pathway by reducing the phosphorylation of p65 and IκBα. CM/G-Rg1 or their combination also reduced the apoptotic rate induced by betulinic acid (BetA), an agonist of the NF-κB signaling pathway. In summary, the combination of CM and G-Rg1 effectively reduced the apoptosis of SOD1^G93A-NSC34 cells through suppressing the NF-κB/Bcl-2 signaling pathway (Fig. 1 is a graphical representation of the abstract).
Humans ; NF-kappa B/metabolism* ; Ginsenosides/pharmacology* ; Amyotrophic Lateral Sclerosis/genetics* ; Culture Media, Conditioned/pharmacology* ; Superoxide Dismutase-1 ; Neurodegenerative Diseases ; Neurons/metabolism* ; Apoptosis