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1.
ACS Cent Sci ; 10(3): 529-542, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38559307

RESUMO

Photoredox catalytic processes offer the potential for precise chemical reactions using light and materials. The central determinant is identified as interfacial charge transfer, which simultaneously engenders distinctive behavior in the overall reaction. An in-depth elucidation of the main mechanism and highlighting of the complexity of interfacial charge transfer can occur through both diffusive and direct transfer models, revealing its potential for sophisticated design in complex transformations. The fundamental photophysics uncover these comprehensive applications and offer a clue for future development. This research contributes to the growing body of knowledge on interfacial charge transfer in photoredox catalysis and sets the stage for further exploration of this fascinating area of research.

2.
Soft Matter ; 18(29): 5518-5523, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35848897

RESUMO

Developing a facile strategy to construct low-cost and efficient proton-conductive electrolytes is pivotal in the practical application of proton exchange membrane (PEM) fuel cells. Herein, a polyamide with in-built -SO3H moieties, PA(PhSO3H)2, was synthesized via a simple one-pot polymeric acylation process. Investigations via electrochemical impedance spectroscopy (EIS) measurements revealed that the fabricated PA(PhSO3H)2 displays a proton conductivity of up to 5.54 × 10-2 S cm-1 at 353 K under 98% relative humidity (RH), which is more than 2 orders of magnitude higher than that of its -SO3H-free analogue PA(Ph)2 (2.38 × 10-4 S cm-1) under the same conditions. Therefore, after mixing with polyacrylonitrile (PAN) at different ratios, PA(PhSO3H)2-based matrix-mixed membranes were subsequently made and the analysis results revealed that the proton conductivity can reach up to 5.82 × 10-2 S cm-1 at 353 K and 98% RH when the weight ratio of PA(PhSO3H)2 : PAN is in 3 : 1 (labeled as PA(PhSO3H)2-PAN(3 : 1)), the value of which is comparable even to those of commercially available electrolytes that are used in PEM fuel cells. In addition, continuous testing shows that PA(PhSO3H)2-PAN(3 : 1) possesses long-life reusability. This work demonstrates that, utilizing the simple reaction of polymeric acylation with a sulfonated module as a precursor, highly effective proton-conductive membranes for PEM fuel cells can be achieved in a facile manner.

3.
Front Plant Sci ; 13: 924154, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35865291

RESUMO

Plants adjust root morphological and/or exudation traits in response to phosphorus (P) mobilization mediated by microorganisms. We hypothesized that straw application coupled with P fertilization would influence microbial P and then root nutrient-acquisition strategies related to crop growth. Root morphological (length and average diameter) and exudation traits (acid phosphatase and carboxylates) of Brassica chinensis, Solanum lycopersicum, Lactuca sativa, and Vigna unguiculata in response to microbial P dynamics were characterized in no-P and P-fertilized soil with/without straw addition. Straw addition increased the growth of fungi and bacteria, stimulating microbial P immobilization at day 24. The high microbial abundance was associated with four tested crops having short roots in straw-amended compared with no-straw soil at day 24. In straw-amended soil, B. chinensis and S. lycopersicum shifted toward root P-acquisition strategies based on fast elongation and strong carboxylate exudation from days 24 to 40. Such effective root P-acquisition strategies together with microbial P release increased shoot P content in S. lycopersicum in straw-amended compared with those without straw at day 40. Conversely, L. sativa and V. unguiculata produced short roots in response to the stable (or even increased) microbial P after straw addition till day 40. In straw-amended soil, high P application stimulated root elongation and carboxylate exudation in L. sativa and V. unguiculata, whereas carboxylate exudation by S. lycopersicum was decreased compared with the straw-amended but non-fertilized treatment at day 40. In summary, root P-acquisition strategies in response to microbial P differed among the tested crop species. Phosphorus fertilization needs to be highlighted when returning straw to enhance P-use efficiency in vegetable cropping systems.

4.
Artigo em Inglês | MEDLINE | ID: mdl-35537034

RESUMO

On account of their inherent reactive properties, radical reactions play an important role in organic syntheses. The booming photochemistry provides a feasible approach to trigger the generation of radical intermediates in organic reaction processes. Thus, developing effective photocatalysts becomes the key step in radical reactions. In this work, the triphenylamine moiety with photoactivity is successfully embedded in a highly porous and stable metal-organic framework (MOF), and the obtained MOF, namely, Zr-TCA, naturally displays a photoactive property derived from the triphenylamine-based ligand. In photocatalytic studies, the triphenylamine-based Zr-TCA not only exhibits a high catalytic activity on the aerobic oxidation of sulfides via the generation of the superoxide radical anion (O2•-) under light irradiation but also shows good efficiency in the trifluoromethylation of arenes and heteroarenes by the formation of the trifluoromethyl radical (CF3•) as an intermediate. Moreover, the high performance of Zr-TCA can be well maintained over a wide range of substrates in these radical reactions, and the recycled Zr-TCA still retains its excellent photocatalytic activity. The high recyclability and catalytic efficiency to various substrates make the constructed triphenylamine-based Zr-TCA a promising photocatalyst in diverse radical reactions.

5.
Inorg Chem ; 60(14): 10089-10094, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34180672

RESUMO

Taking a robust zirconium-based metal-organic framework, UiO-66, as a prototype, functional postmodification via the versatile Cu(I)-catalyzed azide-alkyne "click" reaction was carried out, and sulfonic acid groups were successfully grafted into its skeleton. Characterizations revealed that the MOF network was still well maintained after being treated by "clicked" modification. Investigations by electrochemical impedance spectroscopy measurements revealed that its proton conductivity increases exponentially up to 8.8 × 10-3 S cm-1 at 80 °C and 98% RH, while those of the UiO-66 and UiO-66-NH2 are only 6.3 × 10-6 and 3.5 × 10-6 S cm-1, respectively, at the same condition. Additionally, the continuous test shows it possesses long-life reusability. Such a remarkable enhancement on the proton conductivities and high performance in long-life reusability of the resultant MOF demonstrated that the "click" reaction is a facile reaction in postmodification of robust porous materials toward targeted applications, with which highly promising candidates of proton-conductive electrolytes for applying in proton-exchange-membrane (PEM) fuel cell can be achieved.

6.
ACS Appl Mater Interfaces ; 13(17): 20137-20144, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33886272

RESUMO

A zirconium-based metal-organic framework (MOF) was successfully constructed via solvothermal assembly of a triphenylamine-based tricarboxylate ligand and Zr(IV) salt, the structure simulation of which revealed that it possesses a two-dimensional layered framework with a relatively rare dodecnuclear Zr12 cluster as the inorganic building unit. The inherent photo-responsive property derived from the incorporated photochromic triphenylamine groups combined with its high stability makes the constructed MOF an efficient heterogeneous photocatalyst for the oxidation of sulfides, which is a fundamentally important reaction type in both environmental and pharmaceutical industries. The photocatalytic activity of the constructed MOF was first investigated under various conditions with thioanisole as a representative sulfide substrate. The MOF exhibited both high efficiency and selectivity on aerobic oxidation of thioanisole in methanol utilizing molecular oxygen in air as the oxidant under blue light irradiation for 10 h. Its high photocatalytic performance was also observed when extending the sulfide substrate to diverse thioanisole derivatives and even a sulfur-containing nerve agent simulant (2-chloroethyl ethyl sulfide). The high photocatalytic efficiency and selectivity to a broad set of sulfide substrates make the triphenylamine-incorporating zirconium-based MOF a highly promising heterogeneous photocatalyst.

7.
New Phytol ; 226(1): 244-253, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31536638

RESUMO

Nutrient distribution and neighbours can impact plant growth, but how neighbours shape root-foraging strategy for nutrients is unclear. Here, we explore new patterns of plant foraging for nutrients as affected by neighbours to improve nutrient acquisition. Maize (Zea mays) was grown alone (maize), or with maize (maize/maize) or faba bean (Vicia faba) (maize/faba bean) as a neighbour on one side and with or without a phosphorus (P)-rich zone on the other in a rhizo-box experiment. Maize demonstrated root avoidance in maize/maize, with reduced root growth in 'shared' soil, and increased growth away from its neighbours. Conversely, maize proliferated roots in the proximity of neighbouring faba bean roots that had greater P availability in the rhizosphere (as a result of citrate and acid phosphatase exudation) compared with maize roots. Maize proliferated more roots, but spent less time to reach, and grow out of, the P patches away from neighbours in the maize/maize than in the maize/faba bean experiment. Maize shoot biomass and P uptake were greater in the heterogeneous P treatment with maize/faba bean than with maize/maize system. The foraging strategy of maize roots is an integrated function of heterogeneous distribution of nutrients and neighbouring plants, thus improving nutrient acquisition and maize growth. Understanding the foraging patterns is critical for optimizing nutrient management in crops.


Assuntos
Fósforo , Raízes de Plantas , Zea mays , Nutrientes , Fósforo/metabolismo , Solo
8.
Chemistry ; 26(3): 721-728, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31633255

RESUMO

Dehydration of (S,S)-1,2-bis(1H-benzo[d]imidazol-2-yl)ethane-1,2-diol (H4 L) to (Z)-1,2-bis(1H-benzo[d]imidazol-2-yl)ethenol) (H3 L') was found to be metal-assisted, occurs under solvothermal conditions (H2 O/CH3 OH), and leads to [MnII 4 (H3 L)4 Cl2 ]Cl2 ⋅5 H2 O⋅5 CH3 OH (Mn4 L4 ) and [MnII 4 (H2 L')6 (µ3 -OH)]Cl⋅4 CH3 OH⋅H2 O (Mn4 L'6 ), respectively. Their structures were determined by single-crystal XRD. Extensive ESI-MS studies on solutions and solids of the reaction led to the proposal consisting of an initial stepwise assembly of Mn4 L4 from the reactants via [MnL] and [Mn2 L2 ] below 80 °C, and then disassembly to [MnL] and [MnL2 ] followed by ligand modification before reassembly to Mn4 L'6 via [MnL'], [MnL'2 ], and [Mn2 L'3 ] with increasing solvothermal temperature up to 140 °C. Identification of intermediates [Mn4 Lx L'6-x ] (x=5, 4, 3, 2, 1) in the process further suggested an assembly/disassembly/in situ reaction/reassembly transformation mechanism. These results not only reveal that multiple phase transformations are possible even though they were not realized in the crystalline state, but also help to better understand the complex transformation process between coordination clusters during "black-box" reactions.

9.
Sci Rep ; 9(1): 16188, 2019 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-31700035

RESUMO

Rice-fish mutualistic production systems rationalise the use of water and soil resources in an improved approach to sustainable food production. However, drivers of fungi community structure in paddy soil, including effects of nitrogen (N) application rate, are unclear in these systems. Here, we assessed soil fungi community and soil physicochemical responses in paddy soil to contrasting rates of N application in a rice-fish system. To clarify the mutualistic effects, the rice-fish system was compared with a standard rice monoculture under a 325.5 kg ha-1 N application rate. The results showed that N application rate affected abundance of paddy soil fungi (P < 0.05). Alpha diversity and richness of fungi were lower in the rice-fish system, but evenness increased with a decrease in N application rate, while the rate of N determined diversity of soil fungi in the rice-fish system. Dominant genera in the two systems differed, and soil physicochemical properties were more important drivers of soil fungi community structure in the rice-fish mutualistic system than in rice monoculture. Total N, available N and P regulated the abundance of dominant fungi. Our results indicate that management of soil fungi may contribute to sustainable agricultural production.


Assuntos
Peixes/fisiologia , Fungos , Micobioma/fisiologia , Oryza/crescimento & desenvolvimento , Microbiologia do Solo , Animais , Fungos/classificação , Fungos/crescimento & desenvolvimento , Solo
10.
AoB Plants ; 11(4): plz033, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31285818

RESUMO

Neighbouring plants can affect plant growth through altering root morphological and physiological traits, but how exactly root systems respond to neighbouring plants with varied density, determining nutrient uptake and shoot growth is poorly understood. In a pot-based experiment, rapeseed was grown alone (single rapeseed), or mixed with 3, 6, or 15 Chinese milk vetch plants. As controls, monocropped Chinese milk vetch was grown at the same planting density, 3, 6, or 15 plants per pot. Root interaction between rapeseed and Chinese milk vetch facilitated phosphorus (P) uptake in rapeseed grown with 3 plants of Chinese milk vetch. As the planting density of Chinese milk vetch in mixture increased, there was a decrease in citrate concentration and acid phosphatase activity but an increase in the total root length of Chinese milk vetch per pot, resulting in decreases in rapeseed root biomass, total root length and P uptake when rapeseed was grown with 6 or 15 Chinese milk vetch plants relative to rapeseed grown with 3 plants. These results demonstrate that the enhanced nutrient utilization induced by root interaction at low planting densities was eliminated by the increased planting density of the legume species in rapeseed/Chinese milk vetch mixed cropping system, suggesting that root/rhizosphere management through optimizing legume planting density is important for improving crop productivity and nutrient-use efficiency.

11.
Chemistry ; 25(20): 5177-5185, 2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30740800

RESUMO

For ethene derivatives with large groups the cis-isomer is often quite unstable and unavailable. Herein, we report an exception of two stable coordination complexes, (cis-L)ZnCl2 , starting from trans-1,2-bis(1-R-benzo[d]imidazol-2-yl)ethene (R=H, L1; R=CH3 , L2) ligands under solvothermal condition (T ≥140 °C). Using the intensity of the absorption and luminescence spectra as probes we proposed its progressive cis-to-trans reversal upon irradiation with UV light, which was confirmed by powder X-ray diffraction (PXRD). Similar results observed in the series of (cis-L2)MII Cl2 [M=Fe (4), Co (5), Ni (6)] demonstrate the universal strategy. The results of PXRD, NMR spectroscopy, ESI-MS and DFT calculations support the above conclusion. NMR spectroscopy indicates that irradiation of 1 converts an optimized 71 % of the cis-isomer to trans, whereas the free trans-L1 ligand transforms to only 15 % cis-isomer under similar conditions.

12.
Sci Rep ; 7(1): 10006, 2017 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-28855645

RESUMO

Meteorological factors have been shown to affect the physiology, distribution, and amounts of inhaled allergens. The aim of this study was to develop a model to predict the trends for onset of allergic rhinitis (AR) patients. A total of 10,914 consecutive AR outpatients were assessed for the number of daily patient visits over a period of 4 years. Meteorological data were used to assess the relationship between meteorological factors and AR incidence by time-series data and regression analysis. Predictive models for incidence of AR were established in pollen-, dust mite- and mould-sensitive groups of patients, and the predictive performances of meteorological factors on the incidence of AR were estimated using root mean squared errors (RMSEs). The incidence of pollen-, dust mites- and mould-sensitive AR patients was significantly correlated with minimum temperature, vapour pressure, and sea-level pressure, respectively. The correlation between comprehensive meteorological parametric (CMP) and incidence of AR was higher than the correlation between the individual meteorological parameters and AR incidence. CMP had higher performance than individual meteorological parameters for predicting the incidence of AR patients. These findings suggest that the incidence of pollen-, dust mites- and mould-sensitive AR can be predicted employing models based on prevailing meteorological conditions.


Assuntos
Exposição Ambiental , Conceitos Meteorológicos , Modelos Estatísticos , Rinite Alérgica/epidemiologia , Adulto , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Adulto Jovem
13.
Chin J Integr Med ; 2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-27329149

RESUMO

OBJECTIVE: To analyze the correlations between the incidence of allergic rhinitis (AR) and meteorological variables of previous periods, so as to establish non-linear prediction equations of AR in Beijing area. METHODS: AR patients (10,478 cases) collected from Beijing Tongren Hospital during 2007-2010 and meteorological data (including daily average temperature, daily maximum temperature, daily minimum temperature, daily relative humidity, daily average vapor pressure, daily dew point temperature, daily precipitation, daily average wind speed, sea level pressure, and degree of comfort) collected from Beijing Municipal Meteorological Observatory in the same periods were used for the analysis. Non-linear correlation and regression were adopted to analyze the relationship between AR incidence and meteorological variables of former six-qi stage which was defined according to Yunqi theory of Chinese medicine. Comprehensive meteorological parameter was introduced to establish the predictive model. RESULTS: The high incidence of AR appeared in the 4th qi stage (from the Beginning of Autumn to Autumn Equinox), while the changes of meteorological variables appeared in the 3rd qi stage (from Grain in Beard to Greater Heat), which advanced one phase. The incidence of AR was closely associated with vapor pressure. The correlation coeffifi cients of two predictive models were between 0.8931-0.9176 and all of them have passed signififi cant statistical tests, which showed a satisfactory fifi tting effect. CONCLUSION: Comprehensive meteorological parameters can be used to forecast AR incidence, which is benefifi cial to AR prevention.

14.
New Phytol ; 209(2): 823-31, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26313736

RESUMO

Root growth is influenced by soil nutrients and neighbouring plants, but how these two drivers affect root interactions and regulate plant growth dynamics is poorly understood. Here, interactions between the roots of maize (Zea mays) and faba bean (Vicia faba) are characterized. Maize was grown alone (maize) or with maize (maize/maize) or faba bean (maize/faba bean) as competitors under five levels of phosphorus (P) supply, and with homogeneous or heterogeneous P distribution. Maize had longer root length and greater shoot biomass and P content when grown with faba bean than with maize. At each P supply rate, faba bean had a smaller root system than maize but greater exudation of citrate and acid phosphatase, suggesting a greater capacity to mobilize P in the rhizosphere. Heterogeneous P availability enhanced the root-length density of maize but not faba bean. Maize root proliferation in the P-rich patches was associated with increased shoot P uptake. Increased P availability by localized P application or by the presence of faba bean exudation stimulated root morphological plasticity and increased shoot growth in maize in the maize/faba bean mixture, suggesting that root interactions of neighbouring plants can be modified by increased P availability.


Assuntos
Fósforo/farmacocinética , Raízes de Plantas/crescimento & desenvolvimento , Solo/química , Vicia faba/fisiologia , Zea mays/metabolismo , Agricultura/métodos , Disponibilidade Biológica , Fósforo/metabolismo , Exsudatos de Plantas/metabolismo , Exsudatos de Plantas/farmacologia , Zea mays/efeitos dos fármacos , Zea mays/crescimento & desenvolvimento
15.
Environ Sci Pollut Res Int ; 22(5): 3920-5, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25292298

RESUMO

Haze is an atmospheric phenomenon in which dry particulate pollutants obscure the sky. Haze has been associated with chronic diseases, but its relationship with acute diseases is less clear. We aimed to determine the association between haze and acute cardiovascular, cerebrovascular, and respiratory diseases, in order to determine the influence of haze on human health. We compared the number of cases of acute cardiovascular, cerebrovascular, and respiratory diseases in Beijing Emergency Center between 2006 and 2013, with haze data from Beijing Observatory. The relationship between the number of hazy days and the number of cases of the above types of diseases was analyzed using univariate analyses. Both the number of cases and the number of hazy days showed a rising trend. The average number of cases per day for all three diseases was higher on hazy days than on non-hazy days. There was a positive correlation between the number of hazy days and the number of cases, and this correlation showed a hysteretic quality. Haze has an influence on acute cardiovascular (CVDs), cerebrovascular (CBDs), and respiratory system (RSDs) diseases. Haze seems to have an additive effect, since the associations between haze and number of cases were stronger in the following month than in the preceding month. The increasing trend in the number of hazy days might worsen the problem of haze-related diseases.


Assuntos
Poluição do Ar/efeitos adversos , Material Particulado/efeitos adversos , Transtornos Respiratórios/epidemiologia , Doenças Respiratórias/epidemiologia , China/epidemiologia , Cidades/estatística & dados numéricos , Humanos , Transtornos Respiratórios/etiologia , Doenças Respiratórias/etiologia
16.
Artigo em Chinês | MEDLINE | ID: mdl-24313200

RESUMO

OBJECTIVE: To analyze the correlation between meteorological factors and onset of allergic rhinitis (AR), and to establish the prediction of AR epideminlogical trend. METHODS: According to skin prick test (SPT) data of AR from Beijing Tongren Hospital and meteorological data of Beijing Observatory (2007 -2010) , analyzed the relationship between meteorological factors and onset in patients with AR. To analyze the probability distribution of onset in AR patients, and establish the grade of AR epideminlogical trend index. SPSS 16. O software was used to analyze the data. RESULTS: The peak of onset in patients with AR appeared in 15 - 30 th August. There was significant correlation between the onset of AR patients and air temperature and vapor pressure(r = 0. 7473, F = 206. 13; r =0. 8465, F = 321. 04; all P < 0. 001) , and the peak of air temperature and vapor pressure were one month earlier than the peak of onset AR patients in 4 years. According to the above correlation, nonlinear prediction models of AR were established; used probability grading method, onset index of AR was divided into 4 grades. CONCLUSION: Index grade forecast of AR onset has important guiding significance for AR diagnosis and prophylaxis, offers objective reference information for health departments.


Assuntos
Conceitos Meteorológicos , Rinite Alérgica/epidemiologia , Previsões , Humanos , Pesquisa , Testes Cutâneos , Temperatura
17.
Artigo em Chinês | MEDLINE | ID: mdl-23141390

RESUMO

OBJECTIVE: To analyze the correlation between airborne pollen concentrations and symptoms in patients with pollen allergic rhinitis. METHODS: Durhum sampler was used to collect the pollen concentration and species from June to September in 2011. The clinical skin prick test (SPT) data were analyzed. The patients with pollen allergic rhinitis were divided into pure pollen allergic rhinitis group (pollen group) and pollen combined perennial allergens allergic rhinitis group (combined group). Symptom scores of patients were assessed, and correlation between pollen concentration and onset of symptoms of patients were analyzed. SPSS 16.0 software was used to analyse the data. RESULTS: While the peak of Summer-Autumn pollen concentration appeared from August 20 to September 15, the major pollen included Artemisia L, Chenopodium album and Humulus scandens. The peak of pollen concentration in one day reached 638/1000 mm(2). The patients taken SPT from June to September accounted for 51.9% of the patients in whole year, among which SPT pollen positive patients were 1509, 60.7% of all SPT positive patients. The amount and rate of SPT positive patients showed significant correlation with pollen concentration(r value were 0.90 and 0.99, both P < 0.05). Onset of symptoms in two groups was correlated with pollen concentration in Summer-Autumn. Symptoms of cough in combined group showed more severe compared with patients with pollen group (t = 2.36, P < 0.05). CONCLUSIONS: Pollen concentration has a major effect on onset of symptoms of allergic rhinitis. Airborne pollen monitoring has important preventive and therapeutic significance on patients with allergic rhinitis.


Assuntos
Alérgenos , Pólen , Rinite Alérgica Sazonal/epidemiologia , Estações do Ano , Adolescente , Adulto , Ar/análise , Alérgenos/imunologia , Criança , Monitoramento Ambiental , Humanos , Pessoa de Meia-Idade , Pólen/imunologia , Rinite Alérgica Sazonal/diagnóstico , Testes Cutâneos , Adulto Jovem
18.
Sci Total Environ ; 417-418: 39-44, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22261403

RESUMO

To investigate the effects of aerosol pollen on human health, we carried out a time-series analysis of daily general practitioner consultations for allergic rhinitis (AR) in Beijing. The objective of this study was to assess the possible effects of pollen on clinic visits for allergic rhinitis in Beijing during the pollen season. We found a strong association between the concentration of pollen in ambient air and the number of consultations for allergic rhinitis. Females had significantly more outpatient visits than males when the levels of pollen increased. Young people (20-60 years old) had had significantly more outpatient visits than older people (over 60 years old) when the levels of pollen increased. After adjusting for air pollutants, the relative risks of pollen on daily number of outpatient for AR were increased.


Assuntos
Pólen/imunologia , Rinite Alérgica Sazonal/imunologia , Adulto , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Visita a Consultório Médico/estatística & dados numéricos , Pacientes Ambulatoriais/estatística & dados numéricos , Rinite Alérgica Sazonal/epidemiologia , Estações do Ano , Adulto Jovem
19.
Chin J Integr Med ; 17(8): 600-6, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21826594

RESUMO

OBJECTIVE: To investigate the relationship between respiratory diseases onset and the meteorological factors in the same period and in a specific environment. METHODS METHODS: By using the data of daily incidence of respiratory diseases obtained from Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine from January 1, 1998 to December 31, 2007, and the data of 16 items of meteorological factors (such as the average, maximum, and minimum temperatures, etc., including meteorological factors derived) obtained from the Beijing Municipal Meteorological Observatory, mathematical statistical methods were applied to achieve the non-linear correlation analysis, or the correlation test, between the incidence of respiratory diseases and the time-related meteorological factors. RESULTS: The simple correlation coefficients of the relationship between the incidence of respiratory diseases and 9 meteorological elements, including the average values of temperature, maximum temperature, minimum temperature, degree of comfort, precipitation, vapor pressure, low cloud cover, change of vapor pressure, and change of wind speed, were all greater than 0.8286, in which one of the relationship between the incidence of respiratory diseases and the maximum temperature is as high as 0.9670. Statistical tests showed R>Rα=0.05 and F>Fα=0.05. CONCLUSIONS: The incidence of respiratory diseases was closely correlated to meteorological factors, such as air temperature, vapor pressure, precipitation, wind speed, etc. To a certain extent, this conclusion confirmed the scientificity and objectivity of the theory of five evolutive phases and six climatic factors (Wu Yun Liu Qi ) in Huang Di Nei Jing (The Yellow Emperor's Canon of Internal Medicine).


Assuntos
Conceitos Meteorológicos , Doenças Respiratórias/epidemiologia , Doenças Respiratórias/etiologia , Estatística como Assunto , Ar , China/epidemiologia , Humanos , Umidade , Incidência , Medicina Tradicional Chinesa , Vapor , Fatores de Tempo , Vento
20.
Zhongguo Zhong Yao Za Zhi ; 30(13): 1001-5, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16161429

RESUMO

OBJECTIVE: To study the effect of Hongjingtian (Gadol) injection on cardiac hemodynamics and myocardial oxygen consumption for analyzing its underlying mechanism in the treatment of coronary heart disease. METHOD: A total of 20 dogs anesthetized with pentobarbital sodium (30 mg x kg(-1), i.v.) were evenly randomized into control group, low-dose Gadol (LDG) group, high-dose Gadol (HDG) group and Herbesser Injection group. The blood flow volume (BFV) of the left coronary artery and cardiac output (CO), left ventricular pressure (LVP), maximum ascending rate (dp/dtmax) of LVP, mean arterial pressure (MAP) of the femoral artery, oxygen contents of the coronary artery and coronary vein (venous sinus), oxygen consumption index (OCI), cardiac index (CI), coronary artery resistance (CAR) and total peripheral resistance (TPR) as well as oxygen utilization rate (OUR) were detected respectively. RESULT: After venous injection of Gadol, CAR, MAP, TPR, OCI, myocardial oxygen consumption and heart rate lowered significantly (P < 0.05-0.01), while BFV and blood oxygen content of the venous sinus increased considerably (P < 0.05-0.01) in comparison with pre-injection. No significant differences were found in LVP and myocardial contractivity between control group and LDG, and between control and HDG groups respectively. CONCLUSION: It showed dilation of the coronary artery and reduction of the cardiac afterload after injection of Gadol. Besides, CO and stroke volume increased considerably and the cardiac effective work was raised without any significant simultaneous increase of both myocardial contractility and LVP. A decrease in the myocardial oxygen consumption and reduction of OCI indicates an improvement of the oxygen supply of the myocardium, and a favorable regulation of the compliance of the cardiac vessels. As a result, the cardiovascular performance was ameliorated. The abovementioned improvement of these indexes may contribute to the therapeutic effect of Gadol in the treatment of coronary heart disease in clinic.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Hemodinâmica/efeitos dos fármacos , Miocárdio/metabolismo , Rhodiola , Animais , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Cães , Medicamentos de Ervas Chinesas/isolamento & purificação , Feminino , Frequência Cardíaca/efeitos dos fármacos , Injeções Intravenosas , Masculino , Oxigênio/metabolismo , Plantas Medicinais/química , Distribuição Aleatória , Rhodiola/química , Resistência Vascular/efeitos dos fármacos
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