1.Study of characteristics of zirconia toughened glass infiltrated nanometer-ceramic composite powder(Al_2O_3/nZrO_2)
Feng CHAI ; Ling XU ; Yunmao LIAO
Journal of Practical Stomatology 2000;0(06):-
Objective: To investigate the properties of zirconia toughened glass infiltrated nanometer-ceramic composite (Al 2O 3/nZrO 2) . Methods: Zirconia toughened glass infiltrated nanometer-ceramic composite(Al 2O 3/nZrO 2)powder was prepared with combination of chemical co-precipitation method and ball milling. The shape, size, partical distribution, crystal phase and chemical composition were measured and analyzed. Results: (1) The crystal phase composition of the studied nanometer ceramic composite powder was made up with ?-Al 2O 3, t-ZrO 2 and m-ZrO 2 examined by XRD?(2) The density of the powder was 4.12 g/cm 3?(3) The particle distribution of the powder ranged 0.02~3.0 ?m?(4)Observed with SEM, the particle profile of the powder was regular, the ratio of length and width of the particles was about 1.2. Conclusion: The studied nanometer ceramic composite powder owns good homogeneity, stable chemical composition, reasonable powder-size gradation and may be favourable in the improvement of the packing density of ceramics.
2.Determination Optimization of Peimine and Peiminine in Three Varieties of Fritillaria
Ling XU ; Wenbing PENG ; Songqiao FENG
China Pharmacist 2015;(8):1299-1301,1302
To establish an optimized determination method for the alkaloids peimine and peiminine in three varieties of Fritillaria. Methods:The samples were refluxed in a mixed solution, the pH value of the mixed solution was adjusted, and then the solution was extracted by ether to obtain the test solution. A Shim-pack VP-ODS column (4. 6 mm × 250 mm,5 μm) was used, the mobile phase consisted of acetonitrile-0. 02% diethylamine(75∶25), and the flow rate was 1. 0 ml·min-1. An Alltech 2000ES ELSD detector was used, the drift tube temperature and the flow rate of nitrogen carrier gas in the ELSD was set at 93℃ and 2. 4 L·min-1 , respectively. The regression equation was calculated between the logarithm values of the reference solution concentration and the corre-sponding peak area. Results:The method could effectively extract the alkaloids from the samples. Peimine and peiminine were well separated by the method, and showed good linearity within the respectively given ranges. The average recovery of the alkaloids in the three varieties of Fritillaria was within the range of 95. 22%-103. 51%. Conclusion: The method is simple,convenient and universal with easy operation,which provides references for the determination of alkaloids in the other varieties of Fritillaria.
4.Promethazine should not be used for infants.
Feng-ling XU ; Ya-ming ZHANG ; Ying-ji JIN
Chinese Journal of Pediatrics 2010;48(7):557-557
5.Effect of pretreatment on topochemical and ultrastructural changes of lignocellulose plant cell walls: a review.
Zhe JI ; Zhe LING ; Xun ZHANG ; Jianfeng MA ; Feng XU
Chinese Journal of Biotechnology 2014;30(5):707-715
Deconstruction of lignocellulosic plant cell walls to fermentable sugars by biochemical means is impeded by several poorly understood ultrastructural and chemical barriers. Pretreatment is an essential step by altering the morphological and compositional characteristics of biomass to enhance the sugar release during enzymatic hydrolysis. Therefore, getting insight into this field is necessary to improve the conversion of biomass into biofuels. In this review, we highlight our recent understanding on the impact of various promising pretreatments on biomass, with emphasis on the topochemical and ultrastructural changes of plant cell walls that are related to the reduction of recalcitrance and the consequence of saccharification. It will lend support to the scientific research and development with respect to biomass conversion.
Biofuels
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Biomass
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Carbohydrates
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chemistry
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Cell Wall
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ultrastructure
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Fermentation
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Hydrolysis
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Lignin
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chemistry
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Plant Cells
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ultrastructure
6.China' s process and challenges in achieving the United Nations Millennium Development Goal 5
Xinglin FENG ; Qing YANG ; Ling XU ; Yan WANG ; Yan GUO
Journal of Peking University(Health Sciences) 2011;43(3):391-396
Objective:China was categorized as one of the 68 countdown countries to achieve the United Nations Millennium Development Goals (MDG) 5. This paper aimed to analyze the situation of maternal survival, and coverage of proven cost effective interventions in China, where specific attention was paid to disparities. Methods: National maternal and child mortality surveillance data were used to estimate maternal mortality ratio (MMR). Coverage for proven interventions was analyzed based on National Health Services Survey, where experts' consultations were made for complementation. Results: There had been a significant reduction of MMR in China, however great disparities existed, with rural Ⅱ to Ⅳ areas experiencing 2 to 5 times higher maternal mortality risks than urban areas and accounting for over 70% maternal mortality burdens. Postpartum hemorrhage, pregnancy associated hypertension, embolism and sepsis were the leading causes, and over 75% of the maternal mortality was caused by preventable or curable causes. Maternal health services utilization decreased in accordance with region' s development level. Socioeconomic factors like financial difficulties were the main obstacles hindering access of care.Even those who made deliveries in hospitals faced different probabilities in receiving qualified care according to their socioeconomic standings. Conclusion: China is on track to achieve MDG 5, however great disparities exist. It is necessary to specifically target rural types Ⅱ to Ⅳ areas. Major causes of maternal mortality which can be prevented or averted through the provision of essential obstetrical care. Yet as compared with maternity health needs, insufficient coverage of maternal and child health (MCH) care services and poor service quality are the leading predisposing factors contributing to maternal mortality in China.
7.Molecular characterization of PrM/C and E genome of Japanese encephalitis virus isolate CQ11-66 from Chongqing
Lijuan XU ; Hua LING ; Sheng YE ; Yan FENG ; Chaomin ZHU
Chinese Journal of Microbiology and Immunology 2012;32(8):734-739
Objective To analyze the molecular characterization of PrM/C and E genome of Japanese encephalitis virus(JEV) strain,CQ11-66,a newly strain isolated from patients with epidemic encephalitis B Chongqing Municipal.Methods The samples were collected from Children's Hospital of Chongqing Medical University,and inoculating BHK-21 cells were used to detect and isolate the Japanese encephalitis virus(JEV) strain,computer analysis of the phylogenetic,nucleic acid data and deduced amino acid sequence was accomplished using the Clustal X(1.8) and MEGA5 programs.Results Only one JEV strain was isolated from patient's cerebrospinal fluid specimen,named CQ11-66.Comparison of the PrM/C genome sequence of strain CQ11-66 with other 31 JEV isolates showed a 74.8%-97.4% nucleotide sequence homology among them,which resulted in 85.6%-98.7% amino acid sequence homology; Meanwhile,comparison of the E genome sequence of strain CQ11-66 with other 35 JEV isolates showed a 81.6%-99.6% nucleotide sequence homology among them,which resulted in 94.8%-99.6% amino acid sequence homology.There were high homology between CQ11-66 and JEV isolates from Fujian province on nucleotide sequence and amino acid sequence.Phylogenetic analysis of PrM/C and E genome showed that the CQ11-66 belonged to genotype Ⅲ.Conclusion Only one JEV strain was isolated from patient's cerebrospinal fluid specimen.There were some differences between CQ11-66 strain and other JEV isolates,and CQ11-66 strain belonged to genotype Ⅲ.
9.Clinical value of heart rate deceleration capacity test in predicting epirubicin-induced cardiotoxicity
Yanying FENG ; Zhijun YANG ; Xu PENG ; Yiman MENG ; Hong LING
Chinese Journal of Clinical Oncology 2015;(13):648-652
Objective:To investigate the effectiveness of heart rate deceleration capacity (DC) measurement in predicting the car-diotoxicity of malignant tumor patients treated with epirubicin-based chemotherapy. Methods:The clinical medical records, including CK-MB and cTnI levels and dynamic electrocardiogram (ECG) parameters before and after each chemotherapy cycle, of 140 patients treated with epirubicin-based chemotherapy were analyzed. Patients were divided into the DC>4.5 ms group and the DC≤4.5 ms group based on the calculated DC values. The CK-MB and cTnI levels and the dynamic ECG parameters of the two groups were compared af-ter two and four cycles of chemotherapy. Results:Patients in the two groups exhibited no statistically significant difference in their rele-vant clinical and pathological data before receiving chemotherapy (P>0.05). However, after four cycles of chemotherapy, the DC≤4.5 ms group showed a significantly greater increase in serum CK-MB and cTnI concentrations over the pre-chemotherapy levels compared with the DC>4.5 ms group. After two and four cycles of chemotherapy, the DC≤4.5 ms group also exhibited a significantly greater in-crease in mean heart rate (beats/min) and supraventricular and ventricular arrhythmia counts (times/24 h) over the pre-chemotherapy values compared with the DC>4.5 ms group (P<0.05). After four cycles of chemotherapy, 23 cases showed abnormally elevated cTnI levels in the DC≤4.5 ms group. In this group, patients with elevated cTnI level exhibited no statistically significant difference in CK-MB and cTnI concentrations, mean heart rates, and supraventricular and ventricular arrhythmia counts compared with those with nor-mal cTnI level before chemotherapy (P>0.05). However, the DC values of patients with elevated cTnI were significantly lower than those with normal cTnI level (P<0.05). Conclusion:The risk of epirubicin-induced cardiotoxicity increased with decrease in DC value. The DC test was shown to be an effective predictor of the risk of epirubicin-induced cardiotoxicity.
10.Protective effects of high-dose ambroxol hydrochloride on traumatic brain injury patients treated by mild hypothermia
Long BAO ; Feng XU ; Li DING ; Weihua LING
Chinese Journal of Geriatrics 2013;32(7):723-726
Objective To explore the effects of high-dose ambroxol hydrochloride (Mucosolvan) on pulmonary protection and anti-inflammatory in traumatic brain injury patients treated by mild hypothermia.Methods From June 2008 to June 2012,40 elderly traumatic brain injury patients aged 60-70 years treated by mild hypothermia in our hospital were selected.Patients were randomly divided into two groups:low-dose ambroxol hydrochloride group and high dose ambroxol hydrochloride (n=20,each).Patients in low-dose ambroxol hydrochloride group were treated with ambroxol 30 mg plus saline infusion,3 times/day; while patients in high-dose ambroxol hydrochloride group were treated with ambroxol 300mg plus saline infusion,3 times/day; both groups were treated for 7 days.The changes of characteristic and quantity of sputum,PaO2and PaO2/FiO2,and serum TNF α level were analyzed at day 1,3,7.Duration of mechanical ventilation,tracheotomy proportion,and mortality were compared between the two groups 3 months after treatment.Results At day 3-7 after the intervention,the sputum got thinner and less,and more easy to suck in highdose group than in low-dose group (thin sputum proportion:75% vs.40%,P =0.025; clean proportion by once suction:65% vs.25%,P=0.011).The improvement of PaO2,PaO2/FiO2 were more significant in high dose group than in low dose group (PaO2 ∶ 3d,(92.3±12.3) mm Hg vs.(83.3±15.2) mm Hg,P=0.046;7d,(95.9±12.5) mm Hgvs.(87.1±11.7) mm Hg,P=0.028;PaO2/FiO2∶3d,(290.8± 15.8) mmHgvs.(221.8± 16.4) mm Hg,P=0.000;7d,(296.3±16.9)mm Hg vs.(238.4±15.0) mm Hg,P=0.000).Serum concentrations of TNF α was lower in highdose group than in low dose group [3d,(54.1± 4.9) ng/L vs.(71.4± 5.6) ng/L,P=0.000;7d,(35.1± 2.7) ng/L vs.(63.3±4.3) ng/L,P 0.000].Duration of mechanical ventilation was shorter and tracheotomy proportion was lower in high dose group than in low dose group [(116.8±18.7) hrsvs.(178.4±35.5) hrs,P=0.000; 25% vs.60%,P=0.025].There was no significant difference in mortality between groups 3 months after treatment.Conclusions The application of high dose ambroxol can improve respiratory function,decrease duration of mechanical ventilation and tracheostomy proportion,and reduce the systemic inflammatory response in elderly traumatic brain injury patients treated by mild hypothermia,but without long-term survival benefit.