다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

Thermo- and pH-responsive polymers in drug delivery.

The climates of Asia are affected significantly by the extent and height of the Himalayan mountains and the Tibetan plateau1,2,3,4 Uplift of this region began about 50 Myr ago, and further significant increases in altitude of the Tibetan plateau are thought to have occurred about 10–8 Myr ago4,5, or more recently However, the climatic consequences of this uplift remain unclear Here we use records of aeolian sediments from China6,7 and marine sediments from the Indian8,9,10 and North Pacific oceans11 to identify three stages of evolution of Asian climates: first, enhanced aridity in the Asian interior and onset of the Indian and east Asian monsoons, about 9–8 Myr ago; next, continued intensification of the east Asian summer and winter monsoons, together with increased dust transport to the North Pacific Ocean11, about 36–26 Myr ago; and last, increased variability and possible weakening of the Indian and east Asian summer monsoons and continued strengthening of the east Asian winter monsoon since about 26 Myr ago The results of a numerical climate-model experiment, using idealized stepwise increases of mountain–plateau elevation, support the argument that the stages in evolution of Asian monsoons are linked to phases of Himalaya–Tibetan plateau uplift and to Northern Hemisphere glaciation

Evolution of Asian monsoons and phased uplift of the Himalaya–Tibetan plateau since Late Miocene times

Using a newly prepared nearly monodisperse (Mw/Mn < 1.05) high molar mass (Mw = 1.3 107 g/mol) poly(N-isopropylacrylamide) (PNIPAM) sample, we successfully, for the first time, made the conformation of individual PNIPAM chains change from a coil to a fully collapsed thermodynamically stable single chain globule and then back to a coil in an extremely dilute aqueous solution (6.7 10-7 g/mL). The average chain density in the globule state is 0.34 g/mL, close to 0.40 g/cm3 predicted on the basis of a space-filling model, indicating that the globule still contains 66% water even in its fully collapsed state. At a given temperature around the lower critical solution temperature, the chains are smaller in the globule-to-coil transition than in the coil-to-globule transition, revealing that the coil-to-globule transition is an irreversible process. The hysteresis can be attributed to the formation of intrachain structures, presumably the intrachain hydrogen bonding, in the globule state. We confirmed the existen...

Comparison of the Coil-to-Globule and the Globule-to-Coil Transitions of a Single Poly(N-isopropylacrylamide) Homopolymer Chain in Water

Using a nearly monodisperse high molar mass poly( $N$-isopropylacrylamide) (PNIPAM) sample, we successfully made the conformation change of individual PNIPAM chains from a coil to a fully collapsed stable single chain globule in an extremely dilute aqueous solution, which enabled us to study for the first time the globule-to-coil transition of a single homopolymer chain in solution. A comparison to the coil-to-globule and the globule-to-coil transitions revealed a hysteresis in the globule-to-coil transition. Our results also confirmed the existence of two additional thermodynamically stable states between the coil and the globule states, namely, the crumpled coil and the molten globule.

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Globule-to-Coil Transition of a Single Homopolymer Chain in Solution

The coil-to-globule transition of a single chain of narrowly distributed (Mz/Mw lo7 glmol) poly(N-isopropylacrylamide) in extremely dilute solutions (-5 pgl mL) was studied by both static and dynamic laser light scattering. The thermodynamically stable collapsed globule (R&?h = 0.97) was observed for the first time. However, when R.&, < 0.97, the single-chain globules were "metastable"; Le., the globules in the solution were stable only for a finite time. Two-stage chain collapsing kinetics in the thermodynamically stable region was observed. The time scales (-lo2 s) observed in both the chain collapsing and dissolving processes are too short to support the previously suggested high chain-knotting density inside the globule. The R&, can be as low as -0.62, lower than 0.774 predicted for a uniform density sphere. This paradox suggests that the chain density is higher at the center of the globule than that near the surface. The highly collapsed globule still contains -80% water in its hydrodynamic volume.

Laser Light Scattering Study of the Phase Transition of Poly(N-isopropylacrylamide) in Water. 1. Single Chain

Using a combination of static and dynamic laser scattering, we examined the association and dissociation of linear poly(N-isopropylacrylamide) (PNIPAM) chains in dilute aqueous solutions There exists a hysteresis in the temperature dependence of the average hydrodynamic radius (〈Rh〉), average radius of gyration (〈Rg〉), and apparent weight-average molar mass (Mw,app) in one heating-and-cooling cycle In the heating process, the chains first undergo intrachain contraction before interchain association to form stable aggregates at temperatures much higher than the lower critical solution temperature (LCST ∼ 32 °C) of PNIPAM in water In the cooling process before the solution temperature approaches the LCST, Mw,app remains a constant and both 〈Rg〉 and 〈Rh〉 increase, but the ratio of 〈Rg〉/〈Rh〉 decreases In other words, the aggregates undergo an unevenly swelling; namely, the periphery swells more than the center, and there is no chain dissociation FTIR spectra reveal that as the temperature increases, the 

Chi Wu

Papers

Comparison of the Coil-to-Globule and the Globule-to-Coil Transitions of a Single Poly(N-isopropylacrylamide) Homopolymer Chain in Water

Globule-to-Coil Transition of a Single Homopolymer Chain in Solution

Laser Light Scattering Study of the Phase Transition of Poly(N-isopropylacrylamide) in Water. 1. Single Chain

LLS and FTIR Studies on the Hysteresis in Association and Dissociation of Poly(N-isopropylacrylamide) Chains in Water

CD4+CD25+FoxP3+ regulatory T cells suppress Mycobacterium tuberculosis immunity in patients with active disease