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921.
目的 了解洞庭湖区垸内钉螺面积分布现状及分布特点,提出防治对策,为进一步有效消灭垸内钉螺面积工作提供依据.方法 收集2007~2011年湖南省血防工作统计年报表及2011年湖南省垸内钉螺面积核查结果进行统计分析.结果 洞庭湖区垸内有螺单元环境类型以沟渠为主,新发钉螺面积60.5hm2,复发钉螺面积546.1hm2,现有钉螺总面积2 754.6hm2,2011年达灭净标准垸内钉螺面积398.6hm2,占总面积的14.47%.采取的主要措施是药物灭螺和沟渠硬化.结论 洞庭湖区垸内虽有新发、复发钉螺面积,但有螺总面积呈下降趋势.可以采取药物灭螺和沟渠硬化、精养鱼池等防治措施相结合的办法,有效减少垸内钉螺面积和促进当地经济发展.  相似文献   
922.
目的探讨复方甘草酸苷在防治原发性肝癌(PLC)三维适形放疗(3DCRT)后肝损伤的作用。方法 113例PLC患者被随机分为治疗组62例和对照组51例,两组均采用3DCRT治疗,分割剂量为2.6~3.2Gy/次,总剂量为48~60Gy;治疗组同时给予复方甘草酸苷注射液60~100 ml/日,静脉滴注,疗程4周,再改为片剂口服,共2~3个月。结果两组患者放疗后ALT和AST较放疗前均有所升高,但治疗组ALT(51.6±12.6 U/L)和AST(48.3±14.4 U/L)升高程度明显低于对照组(分别为85.2±19.9 U/L和73.8±17.8 U/L,P〈0.01);治疗组发生放射性肝病(RILD)4例(6.5%),而对照组发生10例(19.6%),治疗组明显低于对照组(P〈0.05)。结论复方甘草酸苷能预防和改善PLC患者在3DCRT治疗后的肝损伤,降低RILD的发生率。  相似文献   
923.
AIM: To evaluate therapeutic outcomes of human umbilical cord-derived mesenchymal stem cells (HUC-MSCs) treatment in patients with refractory uveitis. METHODS: A retrospective and noncomparative review was performed on four patients with refractory uveitis from December 2013 to December 2017. HUC-MSCs were administered intravenously at a dose of 1×106 cells/kg. Clinical response, relapse rate, change of visual acuity, and other metrics were evaluated. RESULTS: All four patients presented with responses to HUC-MSCs treatment, with three males and one female. The numbers of uveitis attacks per year after the HUC-MSCs treatment (0, 2, 0, 0 respectively) all decreased compared with the numbers before the treatment (3, 6, 4, 4 respectively). The oral steroid and immunosuppressive agents were tapered in all patients without recrudescence of ocular inflammation, and three patients discontinued their oral medicine at the last visit. The best corrected visual acuity (BCVA) of 3 patients was improved to varying degrees, and the BCVA of 1 patient remained at 20/20 (Snellen chart) from the first to the last consultation. CONCLUSION: The study provides an effective therapy of HUC-MSCs in maintaining remission in patients affected by uveitis refractory to previous immunosuppressant treatments.  相似文献   
924.
A high monosaccharide conversion rate of hemicellulose in a green solvent and under moderate reaction conditions for industrialization is one of the most important keys in a lignocellulosic biorefinery. The behavior of Populus tomentosa hemicellulose polysaccharides, crystallinity and the furfural formation in the autohydrolysis process under moderate subcritical water conditions (160–180 °C, 0.618–1.002 MPa) were studied. The results have shown that the hemicellulose was converted to corresponding monosaccharides at an ultra-high hydrolysis rate. Factor analysis indicates that the temperature is the most important factor affecting hemicellulose autohydrolysis. When the autohydrolysis temperature increased from 160 to 180 °C for 2 h, the hydrolysis rate of xylose, rhamnose, galactose, mannose, and glucose from hemicellulose increased from 70% to 91%, 71% to 100%, 82% to 95%, 42% to 58%, and 34% to 37%, respectively. Arabinose was completely dissolved in 30 min. The xylose, rhamnose, galactose, and arabinose from hemicellulose could be almost completely removed under the conditions. The hemicellulose removal rate obtained herein exceeded the values reported for most acid, alkali, ionic liquid, or deep eutectic solvent treatments. It is notable that almost all glucose in hemicellulose was dissolved and the glucose in cellulose was partially hydrolyzed. An analysis of the sugar composition and the crystallinity change in the process at 180 °C demonstrate that hydrolysis reaction started to shift from amorphous regions to crystalline regions, due to the partial hydrolysis of crystalline cellulose after 90 min at 180 °C. Overall, these results show that the moderate subcritical water autohydrolysis of hemicellulose in Populus tomentosa may be a potential bio-refinery process.

A high monosaccharide conversion rate of hemicellulose in a green solvent and under moderate reaction conditions for industrialization is one of the most important keys in a lignocellulosic biorefinery.  相似文献   
925.
To develop new, more effective and lower toxicity antitumor dihydroartemisinin (DHA) nanocomplexes, a DHA prodrug synthesized in this study was used to prepare DHA prodrug self-assembled nanocomplexes (DHANPs) by molecular self-assembly technology. The optimization, pharmacokinetics and in vitro and in vivo antitumor efficiency of DHANPs were assessed. The results showed that the entrapment efficiency, drug loading, particle size and zeta potential of the optimized formulation were 92.37 ± 3.68%, 76.98 ± 3.07%, 145.9 ± 2.11 nm and −16.0 ± 0.52 mV, respectively. DHANPs had a uniform size distribution and good stability during storage. The release of DHA prodrugs from DHANPs was slow in a PBS solution (pH 7.4). The pharmacokinetic study indicated that DHANPs could significantly improve the blood concentration of DHA. DHANPs exhibited lower cytotoxicity to 4T1 cells. More importantly, DHANPs could increase the quality life of mice in comparison with that of the DHA solution in 4T1 tumor-bearing mice. In short, the optimized DHA prodrug nanocomplexes show good long-term stability during the experimental time, extend the life-cycle of DHA in rats and can act as a prospective nano-drug delivery system for future artemisinin-based anti-tumor drugs.

To develop new, more effective and lower toxicity antitumor dihydroartemisinin (DHA) nanocomplexes, a DHA prodrug synthesized in this study was used to prepare DHA prodrug self-assembled nanocomplexes (DHANPs) by molecular self-assembly technology.  相似文献   
926.
A composite catalyst, Pd/C-SO3H, has been prepared to depolymerize plant-derived polymeric proanthocyanidins (PPC). Different reaction conditions were explored and the catalyst was shown to have good performance and recyclability, as well as good thermal and acid–base stability. UV, FTIR and 1H NMR analyses showed that the depolymerization products (oligomeric proanthocyanidins, OPC) retained a condensed flavanol polyphenol structure and that the basic structural units of the polymers had not been destroyed. The antioxidant activity of the OPC was better than that of the PPC, and also better than that of 2,6-di-tert-butyl-4-methylphenol, which is widely used in industry, including as a food additive. OPC could, therefore, be developed as a commercially useful radical chain-breaking antioxidant. The preparation of Pd/C-SO3H provides an example of the design and development of a new composite catalyst that has high practical value. The study also provides a new technical route for the depolymerization of PPC and thus makes a useful contribution to the high-value utilization of renewable plant resources.

A composite catalyst, Pd/C-SO3H, has been prepared to depolymerize plant-derived polymeric proanthocyanidins (PPC).  相似文献   
927.
Diffusion and sorption of five gases (H2, N2, O2, CO2, CH4) in hydrogenated nitrile butadiene rubber (HNBR) and ethylene–propylene–diene rubber (EPDM) have been investigated by molecular dynamics (MD) and grand canonical Monte Carlo (GCMC) simulations. The diffusion coefficients of gas molecules in HNBR and EPDM are well correlated with the effective penetrant diameter except for CO2. CO2 shows a lower diffusion coefficient due to its linear shape. Additionally, the favorable interaction between CO2 and HNBR is another factor for its lower diffusion coefficient in HNBR. HNBR shows lower diffusion coefficients than EPDM. This is because the polar –CN groups in HNBR chains increase interchain cohesion and result in tight intermolecular packing, low free volume and poor chain mobility, which decreases the diffusion coefficients of HNBR. The solubility coefficients of CH4, O2, N2 and H2 in HNBR are lower than those in EPDM, which is a result of the weak HNBR–penetrant interactions and low free volume of HNBR. However, the solubility coefficient of CO2 in HNBR is higher than in EPDM. This is attributed to the strong interaction between CO2 and HNBR. H2, O2, N2 and CH4 show lower permeability coefficients in HNBR than in EPDM, while CO2 has higher permeability coefficients in HNBR. These molecular details provide critical information for the understanding of structures and gas transport between HNBR and EPDM.

Diffusion and sorption of five gases (H2, N2, O2, CO2, CH4) in HNBR and EPDM were explored by MD and GCMC simulations.  相似文献   
928.
Thermoelectric materials with a large Seebeck coefficient (S) and electrical conductivity (σ) are required to efficiently convert waste heat into electricity, but their interdependence makes simultaneously improving these variables immensely challenging. To address this problem, bilayers (BL) of poly(diallyldimethylammonium chloride) (PDDA) and double-walled carbon nanotubes (DWNT), stabilized by KBr-doped poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) were deposited using layer-by-layer (LbL) assembly. Doping PEDOT:PSS with KBr, prior to DWNT dispersion and LbL assembly, results in a six-fold improvement in electrical conductivity with little change in the Seebeck coefficient. A maximum power factor (PF = S2σ) of 626 ± 39 μW m−1 K−2 is obtained from a 20 BL PDDA/PEDOT:PSS–DWNT film (∼46 nm thick), where PEDOT:PSS was doped with 3 mmol KBr. This large PF is due to the formation of a denser film containing a greater proportion of DWNT, which was influenced by the charge-screening effects imparted by the salt dopant that separates PSS from PEDOT. This study demonstrates a relatively simple strategy to significantly increase the thermoelectric performance of fully organic nanocomposites that are useful for low temperature thermoelectric devices.

Thermoelectric power factor of a polymer nanocomposite film, deposited using layer-by-layer assembly, was increased by doping with KBr.  相似文献   
929.
The highly efficient treatment of azo dye contaminated wastewater from the textile industry is an important but challenging problem. Herein, polydimethylsiloxane (PDMS) microparticles, incorporating multiple-walled carbon nanotubes/titanium dioxide (MWCNTs/TiO2) nanocomposites, were successfully synthesized to treat wastewater containing Rhodamine B (RhB) dyes in a synergetic approach, by combining sorption and photocatalytic degradation. The surfactant wrapping sol–gel method was applied to synthesize MWCNTs/TiO2 nanocomposites with TiO2 nanoparticles evenly distributed on the surface of the MWCNTs. The PDMS microparticles were fabricated with an oil-in-water (O/W) single emulsion template, using needle-based microfluidic devices. MWCNTs/TiO2 nanocomposites (at a weight ratio of 1%, and 2%, respectively) were mixed with the PDMS precursor as the dispersed phase, and an aqueous solution of polyvinyl alcohol (PVA) was used as the continuous phase. Highly monodispersed microparticles, with average diameters of 692.7 μm (Coefficient of Variation, CV = 0.74%) and 678.3 μm (CV = 1.04%), were formed at an applied flow rate of the dispersed and continuous phase of 30 and 200 μL min−1, respectively. The fabricated hybrid microparticles were employed for the treatment of RhB, involving a dark equilibrium for 5 hours and UV irradiation for 3 hours. The experimental conditions of applied PDMS type, mass loading amount, treatment duration, photodegradation kinetics, initial concentration of pollutants and environmental pH values were investigated in this work. The PDMS microparticles with 2 wt% MWCNTs/TiO2 nanocomposites can exhibit a removal efficiency of 85%. Remarkably, an efficiency of 70% can be retained after the microparticles have been recycled and reused for 3 cycles. The PDMS–MWCNTs/TiO2 microparticles possess a superior performance over conventional treatment approaches for dye contaminated wastewater, especially in recyclability and the prevention of secondary pollution. This work provides a feasible and eco-friendly route for developing an efficient and low-cost microfluidic method for treating complicated water environmental systems.

PDMS–MWCNTs/TiO2 microparticles made by microfluidics can achieve 85% removal efficiency of RhB pollutant in wastewater via synergetic treatment.  相似文献   
930.

Introduction and hypothesis

This study evaluated whether bladder trabeculations are associated with advanced prolapse, urinary urgency, or detrusor overactivity among women undergoing office cystoscopy. It is well established that bladder trabeculations are associated with bladder outlet obstruction (BOO) in men; however, the clinical significance of trabeculations in women is unclear. Whereas an analogous relationship has been proposed between prostatic obstruction in men and advanced pelvic organ prolapse (POP) in women, little data in the medical literature supports this theory.

Methods

A retrospective cohort study was conducted using Current Procedural Terminology (CPT) codes (52000, 52204) to identify all women who underwent office cystoscopy at our urogynecology center between January 2008 and May 2011. The 551 women identified were grouped by the presence or absence of bladder trabeculations. Multivariable logistic regression was used to estimate the association between trabeculations and the primary aim, increasing stage of prolapse, and the secondary aims: bladder outlet obstruction, detrusor overactivity, or urge urinary incontinence (UUI).

Results

Of the 551 women meeting inclusion criteria, 86 had trabeculations. Controlling for age, the odds of bladder trabeculations were eightfold greater for women with stage IV POP when compared with women with stage 0 prolapse [odds ratio (OR) 8.2, 95 % confidence interval (CI) 1.6–43.1]. The odds of bladder trabeculations were twofold greater for women with detrusor overactivity (OR 2.3, 95 % CI 1.3–4.0) found on urodynamic study and also as reflected subjectively by answers to Pelvic Floor Distress Inventory (PFDI) item number 16 (OR 4.2, 95 % CI 1.3–14.5).

Conclusion

In this study, bladder trabeculations were associated with stage IV prolapse in the anterior compartment as well as with detrusor overactivity and UUI.  相似文献   
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