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111.
Background
Classical bioconjugation strategies for generating antibody-functionalized nanoparticles are non-specific and typically result in heterogeneous compounds that can be compromised in activity. Expression systems based on self-cleavable intein domains allow the generation of recombinant proteins with a C-terminal thioester, providing a unique handle for site-specific conjugation using native chemical ligation (NCL). However, current methods to generate antibody fragments with C-terminal thioesters require cumbersome refolding procedures, effectively preventing application of NCL for antibody-mediated targeting and molecular imaging. 相似文献112.
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Huho BJ Killeen GF Ferguson HM Tami A Lengeler C Charlwood JD Kihonda A Kihonda J Kachur SP Smith TA Abdulla SM 《Malaria journal》2012,11(1):118
ABSTRACT: BACKGROUND: Artemisinin-based combination therapy (ACT) for treating malaria has activity against immature gametocytes. In theory, this property may complement the effect of terminating otherwise lengthy malaria infections and reducing the parasite reservoir in the human population that can infect vector mosquitoes. However, this has never been verified at a population level in a setting with intense transmission, where chronically infectious asymptomatic carriers are common and cured patients are rapidly and repeatedly re-infected. METHODS: From 2001 to 2004, malaria vector densities were monitored using light traps in three Tanzanian districts. Mosquitoes were dissected to determine parous and oocyst rates. Plasmodium falciparum sporozoite rates were determined by ELISA. Sulphadoxinepyrimethamine (SP) monotherapy was used for treatment of uncomplicated malaria in the contiguous districts of Kilombero and Ulanga throughout this period. In Rufiji district, the standard drug was changed to artesunate co-administered with SP (AS + SP) in March 2003. The effects of this change in case management on malaria parasite infection in the vectors were analysed. RESULTS: Plasmodium falciparum entomological inoculation rates exceeded 300 infective bites per person per year at both sites over the whole period. The introduction of AS + SP in Rufiji was associated with increased oocyst prevalence (OR [95%CI] = 3.9 [2.9-5.3], p < 0.001), but had no consistent effect on sporozoite prevalence (OR [95%CI] = 0.9 [0.7-1.2], p = 0.5). The estimated infectiousness of the human population in Rufiji was very low prior to the change in drug policy. Emergence rates and parous rates of the vectors varied substantially throughout the study period, which affected estimates of infectiousness. The latter consequently cannot be explained by the change in drug policy. CONCLUSIONS: In high perennial transmission settings, only a small proportion of infections in humans are symptomatic or treated, so case management with ACT may have little impact on overall infectiousness of the human population. Variations in infection levels in vectors largely depend on the age distribution of the mosquito population. Benefits of ACT in suppressing transmission are more likely to be evident where transmission is already low or effective vector control is widely implemented. 相似文献
115.
以树发属(Alectoria)化石为校正点,使用RPB2序列和BEAST分析方法估计梅衣科部分类群的分化时间。梅衣科地衣部分谱系的分化发生在白垩纪、古新世到始新世和渐新世;主要属内辐射则发生在晚始新世、早渐新世,并延续到中新世和上新世早期。估计的主要谱系分化时间与古气候条件及古地质区域分支图相呼应。 相似文献
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The effects of chronic phenobarbitone administration and subsequent withdrawal on the activity of rat liver tryptophan pyrrolase and their resemblance to those of ethanol (Short Communication) 下载免费PDF全文
Chronic phenobarbitone administration inhibits the apo-(tryptophan pyrrolase) activity in homogenates of rat liver and subsequent withdrawal enhances the enzyme activity by 2.5-fold. Similar effects have been previously produced by chronic ethanol administration and withdrawal, but, whereas NADH may cause the ethanol inhibition, that by phenobarbitone may be mediated by NADPH. 相似文献
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新疆哈纳斯自然保护区大型地衣初报 总被引:2,自引:1,他引:2
报道新疆哈纳斯自然保护区大型地衣61种,2亚种,6变型;隶属于28属,14科,其中1属为半知地衣,5种为中国新记录,23种为新疆新分布。 相似文献
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