研究了几种淬灭剂对皖南尖吻蝮蛇蛇毒出血毒素 (Aa H )内源荧光的影响。溴代琥珀酰亚胺 (NBS)法测得每个 Aa H 分子中含有 3个 Trp残基。实验得到丙烯酰胺 (Acr)和 I-的碰撞淬灭常数 KSV分别为 38.3M-1和 4.2 7M-1,fa 分别为 0 .97和 0...研究了几种淬灭剂对皖南尖吻蝮蛇蛇毒出血毒素 (Aa H )内源荧光的影响。溴代琥珀酰亚胺 (NBS)法测得每个 Aa H 分子中含有 3个 Trp残基。实验得到丙烯酰胺 (Acr)和 I-的碰撞淬灭常数 KSV分别为 38.3M-1和 4.2 7M-1,fa 分别为 0 .97和 0 .99,Acr和 I-均可以淬灭 Aa H 分子中几乎全部 Trp残基的荧光 ,初步验证 Acr与 Aa H 分子间无明显的相互作用。结合 Aa H 的荧光发射光谱可以推断 ,Aa H 中的 3个展开更多
OBJECTIVE To study the relationship between atypical adenomatous hyperplasia (AAH) and bronchioloalveolar carcinoma (BAC). METHODS Morphometric, immunohistochemical and ultrastructural analyses were performed in 4 pat...OBJECTIVE To study the relationship between atypical adenomatous hyperplasia (AAH) and bronchioloalveolar carcinoma (BAC). METHODS Morphometric, immunohistochemical and ultrastructural analyses were performed in 4 patients with low grade AAH, 5 with high grade AAH and 7 with BAC. RESULTS The mean nuclear areas of high grade AAH and BAC were greater than those of low grade AAH (P<0.05); p53 protein expression was negative in 4 cases of low grade AAH,while the positive rates in high grade AAH and BAC were 40% (2/5) and 57% (4/7), respectively. CONCLUSION The development of BAC is stepwise. AAH appears to be a lesion closely related with BAC, probably as its genuine precursor.展开更多
A low temperature (LoTemp?) polymerase chain reaction (PCR), conducted at cycling temperatures not to exceed 85℃and catalyzed by a novel highly processive HiFi? DNA polymerase with proofreading function, was used to ...A low temperature (LoTemp?) polymerase chain reaction (PCR), conducted at cycling temperatures not to exceed 85℃and catalyzed by a novel highly processive HiFi? DNA polymerase with proofreading function, was used to study the topological conformational changes of the human papillomavirus (HPV) L1 gene DNA fragments bound to the insoluble amorphous aluminum hydroxyphosphate sulfate (AAHS) adjuvant in the quadrivalent HPV vaccine, Gardasil?. L1 gene DNA fragments of HPV-11, HPV-18 and HPV-16 were detected in the AAHS particles by nested PCR, but all were lacking a region that was amplifiable by an MY09 degenerate primer. In addition, a pair of degenerate consensus GP6/MY11 primers was able to amplify a target segment of the HPV-11 L1 gene DNA and the HPV-18 L1 gene DNA bound to the AAHS particles as expected for any HPV DNA in the B-conformation. However, there was no co-amplification of the HPV-16 L1 gene DNA known to coexist in the same samples. The lack of co-amplification was verified by direct DNA sequencing of the PCR amplicons. The companion HPV-16 L1 gene DNA in the same sample required repeated PCRs with a pair of modified non-degenerate GP6/ MY11 primers for detection. This melting profile of the HPV-16 L1 gene DNA was similar to that of the HPV-16 L1 gene DNA recently discovered in the postmortem blood of a young woman who suffered a sudden unexpected death 6 months after Gardasil? vaccination. The findings suggest that the topological conformational changes in the HPV L1 gene DNA residues bound to the AAHS adjuvant may be genotype-related. The special non-B-conformation may prevent the HPV-16 L1 gene DNA from being degraded in the body of the vaccine recipients after in- tramuscular injection.展开更多
皖南尖吻蝮蛇蛇毒经分离和纯化得到出血毒素 (Aa H ) ,质谱测定分子量为 2 32 84.4± 0 .1。实验表明 ,色氨酸 (Trp)残基位于 Aa H 分子的疏水区。十二烷基磺酸钠 (SDS)和盐酸胍的加入使 Aa H 的分子构象发生变化 ,导致分子内 Tr...皖南尖吻蝮蛇蛇毒经分离和纯化得到出血毒素 (Aa H ) ,质谱测定分子量为 2 32 84.4± 0 .1。实验表明 ,色氨酸 (Trp)残基位于 Aa H 分子的疏水区。十二烷基磺酸钠 (SDS)和盐酸胍的加入使 Aa H 的分子构象发生变化 ,导致分子内 Trp残基的荧光淬灭。盐酸胍的加入使 Trp残基的荧光发射峰位明显红移 ,表明位于 Aa H 分子较疏水环境的 Trp残基相对外露。本文还就酸度、EDTA和金属离子对 Aa H 分子内展开更多
文摘研究了几种淬灭剂对皖南尖吻蝮蛇蛇毒出血毒素 (Aa H )内源荧光的影响。溴代琥珀酰亚胺 (NBS)法测得每个 Aa H 分子中含有 3个 Trp残基。实验得到丙烯酰胺 (Acr)和 I-的碰撞淬灭常数 KSV分别为 38.3M-1和 4.2 7M-1,fa 分别为 0 .97和 0 .99,Acr和 I-均可以淬灭 Aa H 分子中几乎全部 Trp残基的荧光 ,初步验证 Acr与 Aa H 分子间无明显的相互作用。结合 Aa H 的荧光发射光谱可以推断 ,Aa H 中的 3个
文摘OBJECTIVE To study the relationship between atypical adenomatous hyperplasia (AAH) and bronchioloalveolar carcinoma (BAC). METHODS Morphometric, immunohistochemical and ultrastructural analyses were performed in 4 patients with low grade AAH, 5 with high grade AAH and 7 with BAC. RESULTS The mean nuclear areas of high grade AAH and BAC were greater than those of low grade AAH (P<0.05); p53 protein expression was negative in 4 cases of low grade AAH,while the positive rates in high grade AAH and BAC were 40% (2/5) and 57% (4/7), respectively. CONCLUSION The development of BAC is stepwise. AAH appears to be a lesion closely related with BAC, probably as its genuine precursor.
文摘A low temperature (LoTemp?) polymerase chain reaction (PCR), conducted at cycling temperatures not to exceed 85℃and catalyzed by a novel highly processive HiFi? DNA polymerase with proofreading function, was used to study the topological conformational changes of the human papillomavirus (HPV) L1 gene DNA fragments bound to the insoluble amorphous aluminum hydroxyphosphate sulfate (AAHS) adjuvant in the quadrivalent HPV vaccine, Gardasil?. L1 gene DNA fragments of HPV-11, HPV-18 and HPV-16 were detected in the AAHS particles by nested PCR, but all were lacking a region that was amplifiable by an MY09 degenerate primer. In addition, a pair of degenerate consensus GP6/MY11 primers was able to amplify a target segment of the HPV-11 L1 gene DNA and the HPV-18 L1 gene DNA bound to the AAHS particles as expected for any HPV DNA in the B-conformation. However, there was no co-amplification of the HPV-16 L1 gene DNA known to coexist in the same samples. The lack of co-amplification was verified by direct DNA sequencing of the PCR amplicons. The companion HPV-16 L1 gene DNA in the same sample required repeated PCRs with a pair of modified non-degenerate GP6/ MY11 primers for detection. This melting profile of the HPV-16 L1 gene DNA was similar to that of the HPV-16 L1 gene DNA recently discovered in the postmortem blood of a young woman who suffered a sudden unexpected death 6 months after Gardasil? vaccination. The findings suggest that the topological conformational changes in the HPV L1 gene DNA residues bound to the AAHS adjuvant may be genotype-related. The special non-B-conformation may prevent the HPV-16 L1 gene DNA from being degraded in the body of the vaccine recipients after in- tramuscular injection.
文摘皖南尖吻蝮蛇蛇毒经分离和纯化得到出血毒素 (Aa H ) ,质谱测定分子量为 2 32 84.4± 0 .1。实验表明 ,色氨酸 (Trp)残基位于 Aa H 分子的疏水区。十二烷基磺酸钠 (SDS)和盐酸胍的加入使 Aa H 的分子构象发生变化 ,导致分子内 Trp残基的荧光淬灭。盐酸胍的加入使 Trp残基的荧光发射峰位明显红移 ,表明位于 Aa H 分子较疏水环境的 Trp残基相对外露。本文还就酸度、EDTA和金属离子对 Aa H 分子内