Ethylene-propylene copolymers were synthesized using a TiCl4/MgCl2/SiO2/diester type supported Ziegler-Natta catalyst with or without the presence of hydrogen in a slurry polymerization process.The copolymer was inhom...Ethylene-propylene copolymers were synthesized using a TiCl4/MgCl2/SiO2/diester type supported Ziegler-Natta catalyst with or without the presence of hydrogen in a slurry polymerization process.The copolymer was inhomogeneous in composition and can be fractionated into two parts, fractions soluble and insoluble in n-octane at room temperature, respectively.The soluble part is a nearly random copolymer,while the insoluble part is a kind of segmented copolymer,as revealed by 13 C-NMR and DSC analyses.Adding H2 in the reaction system caused an increase of copolymer yield and a decrease of the insoluble part,but the propylene content and average length of propylene segments of the insoluble part were markedly increased,meanwhile the average length of ethylene segments of the insoluble part was markedly decreased.Copolymer sequence distribution of the soluble part was only slightly changed by H2. The segmented copolymer fraction present in this ethylene-propylene copolymer has the similar structure as the segmented copolymer fractions found in polypropylene/poly（ethylene-co-propylene） reactor alloy.Mechanism of the hydrogen effect on copolymer structure is discussed.展开更多
Objective:To investigate the application of Ziehl-Neelsen(Z-N) and fluorescent microscopy in detection of acid fast bacilli(AFB).Methods:Duplicate smears were prepared from 260 sputum samples and stained with Z-N and ...Objective:To investigate the application of Ziehl-Neelsen(Z-N) and fluorescent microscopy in detection of acid fast bacilli(AFB).Methods:Duplicate smears were prepared from 260 sputum samples and stained with Z-N and fluorescent staining(FS) methods.The efficiency of both methods in primary diagnosis of tuberculosis were evaluated.Results:The smears were positive for AFB in 15(5.77%) samples by Z-N staining method and in 16(6.15%) samples by FS method.The sensitivity and specificity of Z-N staining method against FS method were 93.75% and 100%respectively.Conclusions:Though lesser cost-effective than Z-N,FS method is a more sensitive and better case finding tool in detection of AFB.展开更多
Objective:To identify the clinical,laboratory,and radiological markers that could predict a positive GeneXpert result in patients suspected of tuberculous meningitis.Methods:In this prospective,observational study,pat...Objective:To identify the clinical,laboratory,and radiological markers that could predict a positive GeneXpert result in patients suspected of tuberculous meningitis.Methods:In this prospective,observational study,patients with tuberculous meningitis were systematically evaluated.Various clinical,laboratory[including cerebrospinal fluid(CSF)microscopy,culture,and GeneXpert],and neuroimaging factors were examined.All participants were administered anti-tuberculous treatment and corticosteroids.A six-month follow-up was done to evaluate the outcome.Results:Of the 116 patients studied,54(46.6%)tested positive for GeneXpert,while 62(53.4%)were negative.Third cranial nerve involvement(OR 3.71,95%CI 1.052-13.09,P=0.04)and the presence of basal exudates on neuroimaging(OR 5.22,95%CI 2.03-13.42,P=0.001)emerged as independent predictive factors for a positive GeneXpert result.A positive CSF GeneXpert result(P=0.002)and drug resistance(P=0.004)were significantly linked to adverse outcomes.Additionally,a high score on the Medical Research Council stageⅢ(OR 5.64,95%CI 1.18-26.87,P=0.03)and elevated CSF cell counts(OR 1.002,95%CI 1.00-1.001,P=0.03)were identified as independent predictors of poor prognosis.Conclusions:Third cranial nerve involvement and the presence of basal exudates were significant indicators of a positive GeneXpert result.MRC stageⅢdisability and elevated CSF cell counts predicted poor outcomes.展开更多
文摘Ethylene-propylene copolymers were synthesized using a TiCl4/MgCl2/SiO2/diester type supported Ziegler-Natta catalyst with or without the presence of hydrogen in a slurry polymerization process.The copolymer was inhomogeneous in composition and can be fractionated into two parts, fractions soluble and insoluble in n-octane at room temperature, respectively.The soluble part is a nearly random copolymer,while the insoluble part is a kind of segmented copolymer,as revealed by 13 C-NMR and DSC analyses.Adding H2 in the reaction system caused an increase of copolymer yield and a decrease of the insoluble part,but the propylene content and average length of propylene segments of the insoluble part were markedly increased,meanwhile the average length of ethylene segments of the insoluble part was markedly decreased.Copolymer sequence distribution of the soluble part was only slightly changed by H2. The segmented copolymer fraction present in this ethylene-propylene copolymer has the similar structure as the segmented copolymer fractions found in polypropylene/poly（ethylene-co-propylene） reactor alloy.Mechanism of the hydrogen effect on copolymer structure is discussed.
文摘Objective:To investigate the application of Ziehl-Neelsen(Z-N) and fluorescent microscopy in detection of acid fast bacilli(AFB).Methods:Duplicate smears were prepared from 260 sputum samples and stained with Z-N and fluorescent staining(FS) methods.The efficiency of both methods in primary diagnosis of tuberculosis were evaluated.Results:The smears were positive for AFB in 15(5.77%) samples by Z-N staining method and in 16(6.15%) samples by FS method.The sensitivity and specificity of Z-N staining method against FS method were 93.75% and 100%respectively.Conclusions:Though lesser cost-effective than Z-N,FS method is a more sensitive and better case finding tool in detection of AFB.
文摘Objective:To identify the clinical,laboratory,and radiological markers that could predict a positive GeneXpert result in patients suspected of tuberculous meningitis.Methods:In this prospective,observational study,patients with tuberculous meningitis were systematically evaluated.Various clinical,laboratory[including cerebrospinal fluid(CSF)microscopy,culture,and GeneXpert],and neuroimaging factors were examined.All participants were administered anti-tuberculous treatment and corticosteroids.A six-month follow-up was done to evaluate the outcome.Results:Of the 116 patients studied,54(46.6%)tested positive for GeneXpert,while 62(53.4%)were negative.Third cranial nerve involvement(OR 3.71,95%CI 1.052-13.09,P=0.04)and the presence of basal exudates on neuroimaging(OR 5.22,95%CI 2.03-13.42,P=0.001)emerged as independent predictive factors for a positive GeneXpert result.A positive CSF GeneXpert result(P=0.002)and drug resistance(P=0.004)were significantly linked to adverse outcomes.Additionally,a high score on the Medical Research Council stageⅢ(OR 5.64,95%CI 1.18-26.87,P=0.03)and elevated CSF cell counts(OR 1.002,95%CI 1.00-1.001,P=0.03)were identified as independent predictors of poor prognosis.Conclusions:Third cranial nerve involvement and the presence of basal exudates were significant indicators of a positive GeneXpert result.MRC stageⅢdisability and elevated CSF cell counts predicted poor outcomes.
