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991.
Graefe's Archive for Clinical and Experimental Ophthalmology - To investigate the etiologies and the clinical characteristics of angle-closure glaucoma (ACG) patients younger than...  相似文献   
992.
Objective To assess the secular trends in the etiology and comorbidity of patients hospitalized with congestive heart failure (CHF).Methods Data of 7319 patients (mean age 59.6 years, 62.1% male) with a primary discharge diagnosis of CHF, hospitalized from January 1, 1993, to December 31, 2007, at the Chinese People’s Liberation Army (PLA) General Hospital were extracted and analyzed. These patients were divided into three groups according to hospitalization period: 1993–1997 (n = 1623), 1998–2002 (n = 2444), and 2003–2007 (n = 3252). The etiological characteristics and comorbidities were assessed. Results Over the study period, the proportion of patients with ischemic heart disease (IHD) increased from 37.2% during the period 1993–1997 to 46.8% during the period 2003–2007, while that with valvular heart disease (VHD) decreased (from 35.2% during the period 1993–1997 to 16.6% during the period 2003–2007, both P < 0.05); Atrial fibrillation (AF) was the most common comorbidity of heart failure (23.2%, 23.0% and 20.6%, respectively, in the three periods); Compared to that of the period of 1993–1997 with that of, the proportion of patients with myocardial infarction, pneumonia, renal function impairment and hepatic cirrhosis of the period of 2003–2007 increased significantly (P < 0.05) and the proportion of patients with chronic obstructive pulmonary disease and atrial fibrillation decreased significantly (P < 0.05). Conclusions This study implies that IHD has became a more common etiology of CHF, while VHD has deceased as an etiology of CHF in Chinese patients during the last two decades.  相似文献   
993.
角膜胶原交联术(CXL)是利用光照射被光敏剂浸润的角膜,诱导角膜中胶原纤维之间以及胶原和其他基质蛋白之间形成共价键(即交联),从而增加角膜硬度并维持角膜生物力学稳定性的一种光化学方法。传统的核黄素-紫外光诱导的角膜胶原交联术(UVX)是以核黄素作为光敏剂,370 nm的紫外光进行照射,虽然能在一定程度上维持角膜生物力学稳定性,但不良反应和局限性也不可忽视。玫瑰红-绿光角膜胶原交联术(RGX)是一种新的CXL技术,以孟加拉玫瑰红作为光敏剂,然后用532 nm的绿光进行照射,可用于治疗圆锥角膜、感染性角膜炎和促进角膜伤口愈合。现将从RGX的原理和过程、安全性与有效性、与UVX的比较及其在眼部的应用研究等进行综述。  相似文献   
994.
AIM: To analyze whether wet-lab training(WLT) or surgical-simulator training(SST) is better for ophthalmology residents to master the chopping technique.METHODS: Sixty ophthalmology residents(in their second year) and three cataract surgeons participated in the study. The residents were randomly separated into two groups, WLT group and SST group. The residents in WLT group were asked to perform 10 trials of chopping using pig eyes and scored by the surgeons, and then they performed and scored using simulator for one time. The residents in SST group underwent 10 trials of chopping using simulator, and the simulator scored each trail. Then, this group were asked to perform the chopping using pig eyes and scored by the surgeons. At last, we investigated the residents’ satisfaction about the training.RESULTS: The demographic characteristics had no significant differences between the two groups. Recorded by the simulator, the residents in SST group got significantly higher overall score(83.90±1.31) than WLT group(78.73±1.92, P=0.03). And the residents in SST group got less corner area injured, and they spend less time than WLT group(P<0.05). Moreover, the residents in WLT group used more ultrasonic energy value than SST group(P=0.03). However, scored by the surgeons, the residents in two groups got nearly the same overall score. The residents in WLT group performed better on the frequencies of posterior capsule torn and incisional stress(P=0.03, 0.008, respectively). In the survey, the residents in two groups held the same opinion that the training was helpful and they strongly recommended this training. And all of them enjoyed the training, and enjoyed being randomized in their own group. However, with respect to the realistic character, the residents thought that WLT was better than SST(P<0.001).CONCLUSION: Both of the Eyesi surgical-stimulator and the wet-lab improve the residents’ chopping ability and each has its own advantages. The combination of the two training ways could be considered to be a part of the training curriculum for new residents.  相似文献   
995.
AIM: To determine the effect of exosomes derived from human umbilical cord blood mesenchymal stem cells (hUCMSCs) on the expression of vascular endothelial growth factor A (VEGF-A) in human retinal vascular endothelial cells (HRECs). METHODS: Exosomes were isolated from hUCMSCs using cryogenic ultracentrifugation and characterized by transmission electron microscopy, Western blotting and nanoparticle tracking analysis. HRECs were randomly divided into a normal control group (group A), a high glucose model group (group B), a high glucose group with 25 μg/mL (group C), 50 μg/mL (group D), and 100 μg/mL exosomes (group E). Twenty-four hours after coculture, the cell proliferation rate was detected using flow cytometry, and the VEGF-A level was detected using immunofluorescence. After coculture 8, 16, and 24h, the expression levels of VEGF-A in each group were detected using PCR and Western blots. RESULTS: The characteristic morphology (membrane structured vesicles) and size (diameter between 50 and 200 nm) were observed under transmission electron microscopy. The average diameter of 122.7 nm was discovered by nanoparticle tracking analysis (NTA). The exosomal markers CD9, CD63, and HSP70 were strongly detected. The proliferation rate of the cells in group B increased after 24h of coculture. Immunofluorescence analyses revealed that the upregulation of VEGF-A expression in HRECs stimulated by high glucose could be downregulated by cocultured hUCMSC-derived exosomes (F=39.03, P<0.01). The upregulation of VEGF-A protein (group C: F=7.96; group D: F=17.29; group E: F=11.89; 8h: F=9.45; 16h: F=12.86; 24h: F=42.28, P<0.05) and mRNA (group C: F=4.137; group D: F=13.64; group E: F=22.19; 8h: F=7.253; 16h: F=16.98; 24h: F=22.62, P<0.05) in HRECs stimulated by high glucose was downregulated by cocultured hUCMSC-derived exosomes (P<0.05). CONCLUSION: hUCMSC-derived exosomes downregulate VEGF-A expression in HRECs stimulated by high glucose in time and concentration dependent manner.  相似文献   
996.
AIM: To investigate the retinal vascular network alterations in eyes of patients with pterygium. METHODS: Totally 18 left eyes from 18 female pterygium patients and 18 left eyes from 18 female healthy control subjects were enrolled. Optical coherence tomography angiography (OCTA) images were generated of the superficial retinal layer and deeper retinal layer of the macular retina for each eye. The microvascular (MIR) and macrovascular (MAR) densities were calculated and MIR, MAR, and total microvascular (TMI) density was compared in the healthy control and pterygium groups. RESULTS: In pterygium group, in the superficial retinal layer, the vascular density in superficial MIR, superior right (SR), inferior right (IR), right (R), superficial central annuli (SC)1, SC2, and SC3 decreased significantly in the macular area (P<0.05). Furthermore, the vascular density in all those decreased regions except R, was significantly and negatively correlated with the disease course (r=-0.6038 to -0.7762, P=0.0008), and the area size of pterygium (r=-0.6043 to -0.9508, P<0.05). For the deeper retinal layer, the density of deep total microvessel (DTMI), deeper MIR, SR, IR, R, DC2, and DC3 decreased significantly in macular area of pterygium patients (P<0.05). Furthermore, the vascular density in all those decreased regions was significantly and negatively correlated with the disease course (r=-0.6901 to -0.7795, P=0.0015), and the area size of pterygium (r=-0.6043 to -0.9563, P<0.05). No statistically significant differences and correlation was found in other region density (|r|<0.47, P>0.05). CONCLUSION: OCTA findings suggest that pterygium patients present with decreased retinal MIR density, and the major vascular alterations occurr mainly on the bitamporal side. The vascular density of the superficial SC1, SC2, SC3 adjacent to the foveal and deep layer of DC2, DC2 regions, significantly decreased.  相似文献   
997.
Novel organic–inorganic hybrid coating materials were developed using amino silanes and acetoacetylated soybean oil. The acetoacetylated soybean oil was prepared from soybean oil (a renewable resource) using a solvent-free method involving a thiol–ene and transesterification reactions, and the chemical structure was characterized by nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), Fourier-transform infrared (FTIR) spectroscopy, and viscosity analyses. On the basis of the acetoacetylated soybean oil, several organic–inorganic hybrid coating materials were prepared using different amino silanes by a catalyst-free method involving one-step comprising two reactions (an amine–acetoacetate reaction and an in situ sol–gel technique), and their crosslinked structures were determined from their FT-IR and solid-state 29Si NMR spectra. The resulting coating materials have good mechanical/chemical performance. This method for preparing renewable organic–inorganic hybrid coating materials may have wide uses because plant oils contain many unsaturated C Created by potrace 1.16, written by Peter Selinger 2001-2019 C bonds and easy access to acetoacetate functional groups.

A novel coating material was synthesized in one-step comprising two reactions (an amine–acetoacetate reaction and an in situ sol–gel technique).  相似文献   
998.
It is both challenging and desirable to have drug sensitizers released at acidic tumor pH for photodynamic therapy in cancer treatment. A pH-responsive carrier was prepared, in which fumed silica-attached 5,10,15,20-tetrakis(4-trimethylammoniophenyl)porphyrin (TTMAPP) was encapsulated into 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) nanocomposite liposomes. The sizes of agglomerates were determined by dynamic light scattering to be 115 nm for silica and 295 nm for silica-TTMAPP-DOPC liposomes. Morphological changes were also found in TEM images, showing liposome formation at pH 8.5 but collapse upon silanol protonation. TTMAPP release is enhanced from 13% at pH 7.5 to 80% at pH 2.3, as determined spectrophotometrically through dialysis membranes. Fluorescence emission of TTMAPP encapsulated in the dry film of liposomes was reduced to half at pH 8.6 when compared to that at pH 5.4, while the production of singlet oxygen was quintupled at pH 5.0 compared to pH 7.6. Upon treatment of human prostate cancer cells with liposomes containing 6.7 μM, 13 μM, 17 μM and 20 μM TTMAPP, the cell viabilities were determined to be 60%, 18%, 20% and 5% at pH 5.4; 58%, 30%, 25% and 10% at pH 6.3; and 90%, 82%, 68% and 35% at pH 7.4, respectively. Light-induced apoptosis in cancerous cells was only observed in the presence of liposomes at pH 6.3 and pH 5.4 but not at pH 7.4, as indicated by chromatin condensation.

Nanocomposite liposomes are relatively stable in weak basic solutions but effectively release porphyrins at acidic pH, as indicated by the difference in fluorescence.  相似文献   
999.
Based on the fluorescence quenching phenomenon, a smart fluorescent microsensor was synthesized. The bifenthrin (BI) microsensor inherited the high selectivity of molecular imprinted polymers (MIPs) and the excellent fluorescence properties of aqueous CdTe quantum dots (QDs). Aqueous CdTe QDs are functionalized by octadecyl-4-vinylbenzyl-dimethyl-ammonium chloride (OVDAC). A type of functional monomer, 4-vinylphenylboronic acid (VPBA), was used and its boronic acid groups could covalently combine with a cis-diol compound for direct imprinting polymerization. The OVDAC-functionalized aqueous CdTe QDs were used as solid supports and auxiliary monomers. Under optimal conditions, experimentation showed that BI had a linear detection range of 10 to 300 μmol L−1 with a correlation coefficient of 0.9968 and a high imprinting factor (IF) of 4.53. In addition, the prepared MIP-OVDAC/CdTe QDs were successfully used to detect BI in water samples. Therefore, this work provided a highly selective and sensitive fluorescence probe for the detection of BI. In addition, the fluorescence probe could be used to detect other targets by changing the functional monomers.

Based on the fluorescence quenching phenomenon, a smart fluorescent microsensor was synthesized.  相似文献   
1000.
Paper-based sensing platforms hold promise in human physiological health monitoring, soft robots, and indoor environment monitoring, owing to their cost effectiveness, flexibility, disposability, and biodegradability. However, most of the existing paper-based sensors require complex fabrication procedures which are also associated with high-cost. Herein, we report a simple yet effective manufacturing process of paper-based carbonaceous sensors based on a laser direct writing (LDW) method. Specifically, carbonaceous pressure, temperature, and humidity sensors on cardboard are developed for human physiological signal monitoring and indoor environment monitoring. Due to the external force induced compaction of the layered carbon flakes, the LDW pressure sensor array has a sensitivity of ∼−0.563 kPa−1, a broad sensing range (0.009–50 kPa), and a high mechanical durability (over 11 000 cycles), all of which are promising for human health monitoring. The LDW-temperature and humidity devices have sensitivities of −0.002/°C and 36.75 fF per %RH, respectively. A prototype is developed using cardboard integrated with temperature and humidity sensors, which not only serves as an ornament to decorate homes but also works as a sensor platform for indoor environment monitoring. Systematic investigation of the LDW manufacturing process, sensing mechanisms, and sensor design and evaluation illustrates the key aspects of carbonaceous sensors.

Carbonaceous sensors on cardboard can be used for human health and indoor environment monitoring.  相似文献   
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