ABSTRACT
Cases of 2019-nCoV nucleic acid and antibody (IgM and IgG total antibody) after discharge from a hospital in Chongqing were continuously monitored. It was found that 5 cases of "re-positive" phenomenon, 5 cases of antibody were positive, and there was a trend of increasing with time. "Re-Positive" may be related to the following three factors. Children with asymptomatic infection had a long time of fecal detoxification.There were two consecutive nucleic acid tests "false negative" caused by various reasons.The virus clearance in patients was not complete, and the discharge standard was not conservative enough. The analysis of the causes of "Re-Positive" patients and the discussion of its infection will help us reveal more characteristics of this virus, and to provide a new basis for the discharge standard in the constantly updated diagnosis and treatment programme.
ABSTRACT
Objective To understand laboratory diagnosis and clinical characteristics of human immunodeficiency virus (HIV ) infection and AIDS patients in three comprehensive hospitals .Methods Laboratory diagnosis and clinical characteristics dates of people living with HIV/AIDS patients consulted in Chongqing Emergency Medical Center between 2007 to 2013 were retrospective‐ly analyzed .Results Totally 47 355 cases were carried HIV antibody screening during 7 years ,179 cases of HIV antibody were positive in preliminary screening ,171 cases were confirmed as positive .Among 5 cases of HIV antibodies result unconfirmed ,2 ca‐ses were followed up ,1 case was ruled out HIV infection ,1 case was converted to HIV antibody positive .People living with HIV al‐ways merging double or multiple infection with hepatitis b virus (HBV) ,hepatitis c virus (HCV) and treponema pallidum (TP) and so on .People living with HIV aged from 18 to 86 years old ,9 .36% was over 60 years old .Most patient has two or more clinical manifestations when consulted a doctor .Conclusion There were false‐positive of HIV antibody preliminary screening ,HIV anti‐body positive results must be confirmed by Western blot confirmatory test .Uncertainty of HIV antibody results should be judged by regularly follow‐up or combining with other detection methods ,epidemiological data .Routine HIV antibody screening should be adopt for HBV ,HCV and TP infection .Elder patients should not be ignored .Clinical specificity of HIV/AIDS is not strong ,it is need to be valued and identified from other cause similar symptoms of diseases caused by phase identification ,in order to reduce missed diagnosis and misdiagnosis .
ABSTRACT
BACKGROUND: Chitosan/poly (3-hydroxybutyrate) (PHB) copolymer has been paid close attention for special biological source of Chitosan and PHB. However, there has been no proper method for them to polymerize effectively.OBJECTIVE: To prepare chitosan/PHB graft copolymer in a homogeneous medium, using a gentle initiator.DESIGN, TIME and SETTING: This study, a single-sample experiment, was performed at the Research Center of Chemistry, Xi'an University of Architecture and Technology, Xi'an, Shaanxi Province, China from August 2007 to October 2007.MATERIALS: Chitosan: DD=100%, Mη=123000, Kyoto, Japan. PHB was purchased from Aldrich chemicals and the molecular weight was 10000.METHODS: Chitosan was grafted with poly (3-hydroxybutyrate) (PHB) in acetic acid/dimethyl sulfoxide system, and benzoyl peroxide (BPO) was used as initiator. The reaction temperature was 85℃ and the reaction continued for 5 hours with nitrogen protection. Grafting reaction and the chemical structure of the copolymer were confirmed by infrared analysis, NMR and elemental analysis. The crystal form and thermal stability of copolymer were characterized with wide-angel X-ray diffraction (WAXD) and thermogravimetric/differential thermal analysis balance, respectively.MAIN OUTCOME MEASURES: The chemical structure of copolymer, crystal form as well as thermal stability.RESULTS: Grafting reaction was confirmed by infrared analysis, NMR and elemental analysis. Wide angle X-ray diffraction and thermogravimetric analysis indicated that graft copolymer was different from chitosan and PHB in crystalline morphology, and had a good thermal stability.CONCLUSION: Using BPO as initiator, chitosan/PHB grafting copolymer is prepared and it has a steady property.