The structure and characteristics of the soluble exopolysaccharide(PS-238) produced by Alcaligenes sp.NX-3 were studied.The analytic sample was prepared by ethanol precipitation then proteins were removed by the Sevag method.The components of polysaccharide were identified by TLC、 GC and chemical method after acid hydrolysis as: glucose,mannose,rhamnose and glucuronic acid.By means of IR and periodate oxidation,it showed that the polysaccharide was mainly consisting of(1→3)and(1→4) glucosidic linkages.The relation between viscosity and shear rate、concentration、temperature、pH and salts was investigated.The results showed that the solution of PS-238 is a typical pseudoplastic liquid,having high viscosity at low concentrations.The viscosity of 1%PS-238 water solution could reach 3300cp at 25℃.It has the excellent stability towards pH2~13,also has outstanding property of viscosity retention even at temperatures up to 150℃.Some kinds of salts were cooperated with PS-238 as a thickening agent.

Sirtuin is a type of deacetylase acted on histone. Sirtuin 1 (SIRT1) is the most homologous to the homologue of silent information regulator 2 (SIR2) in mammals. Its main function is to regulate the body energy metabolism, cell senescence and response to stress. SIRTI inhibits apoptosis through the interaction of several transcription factors involving in stress response. It is a neuroprotective gent.

As a kind of new technology, ethical issues are inevitable in medical and non-medical gene en-hancement application. It is unrealistic to unilaterally support or object to the research and application of medical and non -medical gene enhancement. Based on standardizing the ethical principle of gene enhancement tech-niques, we should build management measures of the research, development and application that adapted to ethi-cal, social and legal standards, so that we can draw on the advantages and avoid the disadvantages, and use gene enhancement reasonably and bring benefits to mankind and society.

Adult ; China ; Female ; Health Status ; Humans ; Male ; Middle Aged ; Occupational Health ; Physical Examination

Objective To get informed of the parents' oral health behaviors,children's oral hygiene habits and the correlation between the two,to lay the foundation of building up joint educational pattern of the oral health between pre-school children and their parents.Methods The questionnaire between preschool children and their parents was applied.By cluster sampling,124 pre-school children from 5 kindergartens in the local community were selected to participate the survey.The oral health behaviors of parents and their kids were investigated and the results underwent analysis.Results Parents’ oral health behaviors were closely related to children's,which was embodied by three parts,such as the starting age of brushing teeth,the duration of brushing and the habits of gargling after meals.As to parents,the knowledge sources of oral health mainly came from TV and broadcast programs (82.3％),newspapers and periodicals,magazines and popular science readings (51.6％),relatives and friends (27.4％),but the anticipated knowledge sources were from medical personnel (90.3％),TV and broadcast programs (53.2％),community activities on health education (51.6％).Conclusions Pre-school children's oral health behaviors are currently good; more emphasis should be laid on the effect of parents' behaviors to their children's oral health; it's necessary to hold more community activities on health education.

Objective: To develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method with cation exchange-based solid phase extraction (SPE) for determination of tetrodotoxin (TTX) in salted pufferfish. Methods: Evenly crushed salted pufferfish samples were subjected to ultrasound-assisted extraction with 0.5% acetic acid/50% methanol/water. The extract was cleaned with cation exchange-based SPE cartridge and eluted with 0.3% hydrochloric acid and 50% acetonitrile/water. The eluent was neutralized with ammonia and separated with a Waters XBridgeTM BEH Amide column (150 mm×3.0 mm, 1.7 μm), and determined using LC-MS/MS in a multiple reaction monitoring mode. Results: The matrix effects of TTX were 85.7%-92.4%, and the matrix suppression effect was under effective control following clean-up procedures using the optimized SPE method. The TTX showed a good linear relationship at the range of 2.0 to 4 000 μg/kg, with a correlation coefficient (r2) of 0.999 2. The limits of detection and quantitation for TTX in sample matrix were 1.0 μg/kg and 2.0 μg/kg, respectively. The mean spiked-recovery rates were 81.2% to 96.5% at spiked amounts of 2.0, 200 μg/kg and 2 200 μg/kg, with relative standard deviations (RSDs) of 4.3% to 7.5%. The intraday accuracy and precision of TTX were 84.4% to 95.6% and 4.9% to 5.8% in quality control samples, and the interday accuracy and precision of TTX were 86.1% to 94.9% and 5.5% to 8.5% in quality control samples. The detection of TTX was 60.5% in 38 market-sold salted pufferfish products using the established LC-MS/MS method. Conclusion The established LC-MS/MS method is effective for accurate quantitative determination of TTX in salted pufferfish.

OBJECTIVE: A series of recent studies have demonstrated the mechanism of migration and nerve net of neural stem cells. These theories have further substantiated neural stem cell transplantation. In view of these new findings, this paper reviewed the mode of migration and information of network. The significance of these theories was discussed.DATA SOURCE: We search on Pubmed with the key words "neural stem cell", "migration", and "nerve net", limiting the language to English and publication date from 1970 to 2004. At the same time we searched on CNKI.STUDY SELECTION: We selected the randomized and non-randomized controlled studies related to migration and nerve net building of neural stem cells. Review articles and articles with repetitive studies were excluded.DATA EXTRACTION: Among 39 papers selected, 16 papers concerning the development of this topic were selected, and the others were excluded.DATA SYNTHESIS: For retrograde lesions and severe injury of nervous system, transplantation of nerve stem cells may replace aging degenerative and dead nerve cells and rebuild neural network for the recovery of cerebral function. Migration of nerve cell and network principle can solve the survival, differentiation, migration and creation of nerve network after transplantation of nerve stem cells so as to realize the recovery and reconstruction of cerebral function.CONCLUSION: Neural stem cells can migrate to intended places and can build nerve net under some conditions, which will be useful for medicine deyelopment.

Objective: To study the diagnosis， treatm ent and outcome of infants in patients with hyperthyroidism in pregnancy. Methods: The levels of T3，T4，TSH，FT3，FT4 in 40 cases of hyperthyroid gravida and control group were measured before delivery, the r oute of delivery and the outcome of infants were studied, and the neonatal thyroid f unctions were evaluated by the levels of T3，T4，TSH in cord serum samples . Results: The levels of T3，T4，FT3，FT4 in non-treatm ent group were higher than that of treatment group and control(P<0.01); an i ncreased rate of forceps and cesarean in hyperthyroid gravida was seen compared with that in control group, about 90%(36/40); the body weights of infants in no n-treatment group were lower than that in treatment and control group. There wa s a case of neonatal hyperthyroidism in non-treatment group. Conclusion : Hyperthyroidism should be diagnosed and treated earlier and there is little side effects on the outcome of infants.

Objective To investigate the presentation and radiologic findings of MarchiafavaBignami disease (MBD).Methods Six cases of MBD who were diagnosed and treated in our hospital were retrospectively analyzed,including the imaging examination(such as cranial CT,magnetic resonance imaging (MRI)),laboratory tests,clinical symptoms and prognosis.Results Six cases of MBD disease were presented with swelled,thickened corpus callosum,iso-or hypo-intensity on T1WI,hyper-intensity on T2WI and fluid attenuated inversion recovery and restricted diffusion on diffusion weighted imaging.Coma of acute onset was the major clinical finding in case 1,case 4 and case 6,which showed the lesions in the entire corpus callosum and extended to the white matter,and the prognosis of these cases were worse.Slow reaction and memory decrease were the clinical findings in case 2 and case 3,which showed the genu and splenium of corpus callosum involvement on MRI and CT,and returned to normal with aggressive treatment.Numbness and weakness of the lower lambs were the major clinical finding in case 5,which showed that the lesion was limited in the splenium and body of corpus callosum on MRI.The patient recovered after treatment.Conclusions MBD may present with various clinical forms,but have characteristic imaging findings.Outset form and neuroimaging characteristics of MBD are critical for improvement of the clinical outcome.

Objective To explore the effect of health education on the blood glucose controlling target in patients with type 2 diabetes. Methods 598 cases of patients with type 2 diabetes were randomly divided into the control group (given conventional treat- ment and medication guide) and the intervention group (besides the above-mentioned treatment, also given diabetes health management program including the systemic health education and promotion, and with stress on behavioral, psychological, dietary intervention) and observed for 7 months. Results After 7 months intervention, there were differences in the levels of glycosylated hemoglobin, fasting plasma glucose and 2h postprandial blood glucose between two groups (P