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971.
To characterize the recurrence of bleeding in patients who had hypertensive intracerebral hemorrhage (HICH), the authors reviewed 989 patients who underwent treatment for HICH between 1989 and 1995. Fifty-three patients (5.4%) had two episodes of HICH within a median interval of 22.9 +/- 16.3 months (range 1.5-72 months), and of these 3 (5.7%) had three episodes of HICH. The recurrence of bleeding most commonly occurred within 2 years of the first hemorrhage: in 66% of the 53 patients the second hemorrhage occurred soon after the first (within 1 year in 34%, within 1-2 years in 32.1%). The site of the second hemorrhage was different from the initial site in all patients. Only 1 patient had a third hemorrhage in the same site as the second hemorrhage. The common patterns of recurrence were 'ganglionic (putamen/caudate nucleus)-thalamic' in 26.8% and 'ganglionic-ganglionic' in 21.4%. The 'lobar-lobar' pattern was noted in only 2 patients. The volume of the hematoma was increased at the second hemorrhage. The overall mortality was 28.3%. The risk of recurrent hemorrhage significantly increased in the patients who had antihypertensive therapy of less than 3 months after the initial attack compared to those with further long-term therapy (p < 0.005). Long-term regular control for hypertension is needed to prevent recurrent hemorrhage. 相似文献
972.
Vasanthan Devaraj Jong-Min Lee Ye-Ji Kim Hyuk Jeong Jin-Woo Oh 《International journal of molecular sciences》2021,22(19)
We reveal the significance of plasmonic nanoparticle’s (NP) shape and its surface morphology en route to an efficient self-assembled plasmonic nanoparticle cluster. A simplified model is simulated in the form of free-space dimer and trimer nanostructures (NPs in the shape of a sphere, cube, and disk). A ~200% to ~125% rise in near-field strength (gap mode enhancement) is observed for spherical NPs in comparison with cubical NPs (from 2 nm to 8 nm gap sizes). Full-width three-quarter maximum reveals better broad-spectral optical performance in a range of ~100 nm (dimer) and ~170 nm (trimer) from spherical NPs as compared to a cube (~60 nm for dimer and trimer). These excellent properties for sphere-based nanostructures are merited from its dipole mode characteristics. 相似文献
973.
974.
Park Su Yeon Choi Sol Ji Park Hee Jeong Ma Sang Yong Moon Yong Il Park Sang-Kyu Jung Mun Yhung 《Food science and biotechnology》2020,29(6):769-775
Food Science and Biotechnology - Squalene is a cancer chemo-preventive and skin protective agent with high commercial demand. Here, we report for the first time that the green tea (Camellia... 相似文献
975.
Mi Jung Kim Mi Suk Jeong Yang Kim Karl Seff 《Microporous and mesoporous materials》1999,30(2-3):233-241
The crystal structures of fully dehydrated Sr46–X [Sr46Si100Al92O384; a=25.214(7) Å] and of its ammonia sorption complex, Sr46–X·102NH3 [Sr46Si100Al92O384·102NH3; a=25.127(7) Å], have been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd
at 21(1)°C. The Sr46–X crystal was prepared by ion exchange in a flowing stream of aqueous 0.05 M Sr(ClO4)2 for 5 days followed by dehydration at 360°C and 2×10−6 Torr for 2 days. To prepare the ammonia sorption complex, another dehydrated Sr46–X crystal was exposed to 230 Torr of zeolitically dried ammonia gas for 1 h followed by evacuation for 12 h at 21(1)°C and 5×10−4 Torr. The structures were refined to the final error indices, R1=0.043 and Rw=0.039 with 466 reflections, and R1=0.049 and Rw=0.044 with 382 reflections, for which I>3σ(I). In dehydrated Sr46–X, all Sr2+ ions are located at two crystallographic sites. 16 Sr2+ ions are at the centers of the double six-rings, filling that site (site I, Sr–O=2.592(6) Å). The remaining 30 Sr2+ ions are in the supercage (site II); each extends 0.56 Å into the supercage from the plane of its three nearest oxygen atoms (Sr–O=2.469(6) Å). In the structure of Sr46–X·102NH3, the Sr2+ ions are located at three crystallographic sites: 12 are found at site I [Sr–O=2.652(10) Å]; four in the sodalite units (site I′) each coordinated to three framework oxygen atoms at 2.654(9) Å and also to three ammonia molecules at 2.76(8) Å. The remaining 30 Sr2+ ions lie at site II. Each extends 1.12 Å into the supercage where it coordinates to three framework oxygen atoms at 2.584(7) Å and also to three ammonia molecules at 2.774(24) Å. 相似文献
976.
977.
Jeong‐Yeol Moon Han‐Jin Jang Kyung‐Hoon Kim Dae‐Won Park Chang‐Sik Ha Jin‐Kook Lee 《应用聚合物科学杂志》2000,77(8):1809-1815
The aim of the study was to investigate the synthesis of a copolymer bearing cyclic carbonate and its miscibility with styrene/acrylonitrile copolymer (SAN) or poly(vinyl chloride) (PVC). (2‐Oxo‐1,3‐dioxolan‐4‐yl)methyl vinyl ether (OVE) as a monomer was synthesized from glycidyl vinyl ether and CO2 using quaternary ammonium chloride salts as catalysts. The highest reaction rate was observed when tetraoctylammonium chloride (TOAC) was used as a catalyst. Even at the atmospheric pressure of CO2, the yield of OVE using TOAC was above 80% after 6 h of reaction at 80°C. The copolymer of OVE and N‐phenylmaleimide (NPM) was prepared by radical copolymerization and was characterized by FTIR and 1H‐NMR spectroscopies and differential scanning calorimetry (DSC). The monomer reactivity ratios were given as r1 (OVE) = 0.53–0.57 and r2 (NPM) = 2.23–2.24 in the copolymerization of OVE and NPM. The films of poly(OVE‐co‐NPM)/SAN and poly(OVE‐co‐NPM)/PVC blends were cast from N‐dimethylformamide. An optical clarity test and DSC analysis showed that poly(OVE‐co‐NPM)/SAN and poly(OVE‐co‐NPM)/PVC blends were both miscible over the whole composition range. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1809–1815, 2000 相似文献
978.
The effects of incorporation of fluorinated alkyl side groups into polyimide membranes were investigated in terms of their physical and gas permeation properties. Four polyimides with fluorinated side groups and four polyimides without the side groups were prepared by polycondensation of 2‐(perfluorohexyl)ethyl‐3, 5‐diamino benzoate (PFDAB) and m‐PDA with four aromatic dianhydrides (6FDA, ODPA, BTDA, and PMDA), respectively. It was found that the incorporation of fluorinated side groups into the polyimide membranes decreased their surface free energies (Tgs), solubility parameters, and fractional free volume (FFV)s and therefore, enhanced the permeabilities for CO2, O2, N2, and CH4 gases but reduced the selectivities for CO2/ CH4, O2 /N2, CO2/N2 gas pairs depending upon the structure of dianhydride monomers. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2756–2767, 2000 相似文献
979.
Raveena Nagareddy Reju George Thomas Yong Yeon Jeong 《International journal of molecular sciences》2021,22(22)
Immunotherapy has been investigated for decades, and it has provided promising results in preclinical studies. The most important issue that hinders researchers from advancing to clinical studies is the delivery system for immunotherapy agents, such as antigens, adjuvants and agonists, and the activation of these agents at the tumour site. Polymers are among the most versatile materials for a variety of treatments and diagnostics, and some polymers are reactive to either endogenous or exogenous stimuli. Utilizing this advantage, researchers have been developing novel and effective polymeric nanomaterials that can deliver immunotherapeutic moieties. In this review, we summarized recent works on stimuli-responsive polymeric nanomaterials that deliver antigens, adjuvants and agonists to tumours for immunotherapy purposes. 相似文献
980.
Jung Sun Park Taeyeon Kim Dohoon Kim Young-IL Jeong 《International journal of molecular sciences》2021,22(22)
The aim of this study is to fabricate reactive oxygen species (ROS)-sensitive nanoparticles composed of succinyl β-cyclodextrin (bCDsu), memantine and thioketal linkages for application in Alzheimer’s disease, and to investigate the suppression of N-methyl-d-aspartate (NMDA) receptor 1 (NMDAR1) in cells. Thioketal diamine was attached to the carboxyl group of bCDsu to produce thioketal-decorated bCDsu conjugates (bCDsu-thioketal conjugates) and memantine was conjugated with thioketal dicarboxylic acid (memantine-thioketal carboxylic acid conjugates). Memantine-thioketal carboxylic acid conjugates were attached to bCDsu-thioketal conjugates to produce bCDsu-thioketal-memantine (bCDsuMema) conjugates. SH-SY5Y neuroblastoma cells and U87MG cells were used for NMDAR1 protein expression and cellular oxidative stress. Nanoparticles of bCDsuMema conjugates were prepared by means of a dialysis procedure. Nanoparticles of bCDsuMema conjugates had small particle sizes less than 100 nm and their morphology was found to be spherical in transmission electron microscopy observations (TEM). Nanoparticles of bCDsuMema conjugates responded to H2O2 and disintegrated or swelled in aqueous solution. Then, the nanoparticles rapidly released memantine according to the concentration of H2O2. In an in vivo animal imaging study, thioketal-decorated nanoparticles labelled with fluorescent dye such as chlorin e6 (Ce6) showed that the fluorescence intensity was stronger in the brain than in other organs, indicating that bCDsuMema nanoparticles can efficiently target the brain. When cells were exposed to H2O2, the viability of cells was time-dependently decreased. Memantine or bCDsuMema nanoparticles did not practically affect the viability of the cells. Furthermore, a western blot assay showed that the oxidative stress produced in cells using H2O2 increased the expression of NMDAR1 protein in both SH-SY5Y and U87MG cells. Memantine or bCDsuMema nanoparticles efficiently suppressed the NMDAR1 protein, which is deeply associated with Alzheimer’s disease. Fluorescence microscopy also showed that H2O2 treatment induced green fluorescence intensity, which represents intracellular ROS levels. Furthermore, H2O2 treatment increased the red fluorescence intensity, which represents the NMDAR1 protein, i.e., oxidative stress increases the expression of NMDAR1 protein level in both SH-SY5Y and U87MG cells. When memantine or bCDsuMema nanoparticles were treated in cells, the oxidative stress-mediated expression of NMDAR1 protein in cells was significantly decreased, indicating that bCDsuMema nanoparticles have the capacity to suppress NMDAR1 expression in brain cells, which has relevance in terms of applications in Alzheimer’s disease. 相似文献