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1.
Ultrasound Med Biol ; 50(6): 946-953, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38514364

RESUMO

OBJECTIVE: Acute lung injury (ALI) has become a research hotspot due to its significant public health impact. To explore the value of the use of modified lung ultrasound (MLUS) scoring system for evaluating ALI using a rabbit model of ALI induced by hydrochloric acid (HCl) and investigate its correlation with high-resolution computed tomography (HRCT) and histopathological scores. METHODS: Twenty New Zealand laboratory rabbits were randomly assigned to control group (N = 5) and 3 experimental groups (N = 5 each). The control group received instillation of physiological saline, while the 3 experimental groups received 2 mL/kg of different doses of HCl instillation (mild group: pH 1.5, moderate group: pH 1.2, and severe group: pH 1.0) through the trachea under ultrasound guidance. Pulmonary ultrasound (using Mindray Reason9 linear array probes with frequency of 6-15 mHz) and HRCT examinations were performed before modeling (0H) and at 1H, 2H, 4H, 8H, 12H after modeling. The experimental rabbits were sacrificed at 12H for examination of gross lung morphology and hematoxylin-eosin-stained histopathological sections. The correlation of MLUS scores with HRCT/histopathological scores was assessed. RESULTS: All rabbits in the experimental groups showed oxygenation index PaO2/FiO2<300. Successful establishment of ALI model was proven by autopsy (successful modeling rate: 100%). The pathological damage increased with increase in HCl dosage. MLUS scores showed a positive correlation with HRCT scores/pathological severity. There was a strong positive correlation between MLUS scores and histopathological scores (r = 0.963, p < 0.05) as well as between HRCT scores and histopathological scores (r = 0.932, p < 0.05). CONCLUSION: Transtracheal injection of different dosages of HCl under ultrasound guidance induced different degrees of ALI. The MLUS scoring system can be used for semiquantitative evaluation of ALI, and is suitable as a screening tool.


Assuntos
Lesão Pulmonar Aguda , Modelos Animais de Doenças , Ácido Clorídrico , Pulmão , Tomografia Computadorizada por Raios X , Ultrassonografia , Animais , Coelhos , Ultrassonografia/métodos , Lesão Pulmonar Aguda/diagnóstico por imagem , Lesão Pulmonar Aguda/induzido quimicamente , Tomografia Computadorizada por Raios X/métodos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Reprodutibilidade dos Testes
2.
Front Plant Sci ; 14: 1136347, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36866379

RESUMO

Climate warming affects rice growth at different phenological stages, thereby increasing rice chalkiness and protein content and reducing eating and cooking quality (ECQ). The structural and physicochemical properties of rice starch played important roles in determining rice quality. However, differences in their response to high temperature during the reproductive stage have been rarely studied. In the present study, they were evaluated and compared between two contrasting natural temperature field conditions, namely, high seasonal temperature (HST) and low seasonal temperature (LST), during the reproductive stage of rice in 2017 and 2018. Compared with LST, HST significantly deteriorated rice quality, including increased grain chalkiness, setback, consistence, and pasting temperature and reduced taste values. HST considerably reduced the total starch and increased the protein content. Likewise, HST significantly reduced the short amylopectin chains [degree of polymerization (DP) <12] and increased the long amylopectin chains (DP > 12) and relative crystallinity. The starch structure, total starch content, and protein content explained 91.4%, 90.4%, and 89.2% of the total variations in pasting properties, taste value, and grain chalkiness degree, respectively. In conclusion, we suggested that rice quality variations were closely associated with the changes in chemical composition content (total starch and protein content) and starch structure in response to HST. These results indicated that we should improve the resistance of rice to high temperature during the reproductive stage to improve the fine structure of rice starch in further breeding and practice.

3.
Front Plant Sci ; 13: 911181, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35865292

RESUMO

Global warming greatly affects the development of rice at different growth stages, thereby deteriorating rice quality. However, the effect of high natural field temperature during reproductive stages on rice quality is unclear. Thus, grain filling dynamics, source-sink characteristics and quality-related traits were compared between two contrasting natural field temperature conditions namely normal (low temperature) (LRT) and hot (high temperature) growth season (HRT) during reproductive stage. Compared with LRT, HRT significantly increased chalky grain rate (about 1.6-3.1%), chalkiness level (about 4.7-22.4%), protein content (about 0.93-1.07%), pasting temperature, setback, and consistence, and decreased total starch content (about 4.6-6.2%). Moreover, HRT significantly reduced the leaf area index (LAI, about 0.54-1.11 m2 m-2), specific leaf weight (SLW, about 1.27-1.44 mg cm-2) and source-sink ratio (leaf-sink ratio and/or stem-sink ratio), shortened the active grain filling period by 3.1-3.2 days, and reduced the rations of dry matter translocation to grain (RDMs). In conclusion, we suggested that significant reduction in assimilate translocation after flowering, resulting in the reduced active grain-filling duration and the poor rice quality (high chalkiness and the poor eating and cooking quality), modulated by source-sink characteristics in response to high natural field temperature during reproductive stage. These results enriched the study of high temperature-stressed rice and served as an important reference for selecting high-quality, heat-tolerant varieties and protecting rice quality under high-temperature conditions.

4.
Environ Pollut ; 306: 119365, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35489537

RESUMO

Rice paddy fields are major sources of atmospheric methane (CH4) and nitrous oxide (N2O). Rice variety is an important factor affecting CH4 and N2O emissions. However, the interactive effects of rice metabolites and microorganisms on CH4 and N2O emissions in paddy fields are not clearly understood. In this study, a high greenhouse gas-emitting cultivar (YL 6) and a low greenhouse gas-emitting cultivar (YY 1540) were used as experimental materials. Metabolomics was used to examine the roots, root exudates, and bulk soil metabolites. High-throughput sequencing was used to determine the microbial community composition. YY 1540 had more secondary metabolites (flavonoids and isoflavonoids) in root exudates than YL 6. It was enriched with the uncultured members of the families Gemmatimonadanceae and Rhizobiales_Incertae_Sedis in bulk soil, and genera Burkholderia-Caballeronia-Paraburkholderia, Magnetospirillum, Aeromonas, and Anaeromyxobacter in roots, contributing to increased expression of pmoA and nosZ genes and reducing CH4 and N2O emissions. YL 6 roots and root exudates contained higher contents of carbohydrates [e.g., 6-O- acetylarbutin and 2-(3- hydroxyphenyl) ethanol 1'-glucoside] than those of YY 1540. They were enriched with genera RBG-16-58-14 in bulk soil and Exiguobacterium, and uncultured member of the Kineosporiaceae family in roots, which contributed to increased expression of mcrA, ammonia-oxidizing archaea, ammonia-oxidizing bacteria, nirS, and nirK genes and greenhouse gas emissions. In general, these results established a link between metabolites, microorganisms, microbial functional genes, and greenhouse gas emissions. The metabolites of root exudates and roots regulated CH4 and N2O emissions by influencing the microbial community composition in bulk soil and roots.


Assuntos
Gases de Efeito Estufa , Microbiota , Oryza , Agricultura , Amônia , Humanos , Metano/análise , Óxido Nitroso/análise , Solo/química
5.
Food Res Int ; 150(Pt A): 110764, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34865781

RESUMO

A field experiment was conducted to explore the impact on rice quality using high-quality (HH) or drought-resistant (HY) cultivars under flooding irrigation (F) or dry cultivation (D) in ratooning rice system by evaluating the metabolism or physicochemical traits of starch, fatty acids, and amino acids affecting grain quality. Compared to FHY and DHY in the main or ratoon season, DHH in ratoon season (DHHR) exhibited a higher appearance and processing quality but lower cooking quality. DHHR mainly synthesized long branch chain amylopectin to construct the crystalline regions with increased crystallinity, crystallites size, interplanar spacing, dislocation density, Asp and Thr in brown and head rice. Also, it accumulated more of C16:0, C18:0, C18:1, C18:2, and C18:3 but reduced glutelin in head rice. An increase in functional groups and diversity was seen in brown and head rice, respectively. Overall, these traits improved the processing, appearance, and pasting quality of DHHR.


Assuntos
Oryza , Aminoácidos , Amilopectina , Farinha , Amido
6.
Foods ; 10(11)2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34829163

RESUMO

Rice quality is a complex indicator, and people are paying more and more attention to the quality of rice. Therefore, we used seven rice varieties for twelve nitrogen fertilizer treatments and obtained eighty-four rice types with seventeen qualities. It was found that 17 quality traits had different coefficients of variation. Among them, the coefficient of variation of chalkiness and protein content was the largest, 44.60% and 17.89% respectively. The cluster analysis method was used to define four categories of different rice qualities. The principal component analysis method was used to comprehensively evaluate 17 qualities of 84 rice. It was found that rice quality was better under low nitrogen conditions, Huanghuazhan and Lvyinzhan were easier to obtain better comprehensive rice quality during cultivation. Future rice research should focus on reducing protein content and increasing peak viscosity.

7.
Carbohydr Polym ; 269: 118336, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34294346

RESUMO

A pot experiment was conducted to explore the effects of high-quality (Huanghuazhan, HH), drought-resistant (IR, IRAT109) and drought-susceptible cultivars (ZS, Zhenshan97) under flooding irrigation and dry cultivation (D) on the starch accumulation and synthesis, physicochemical traits of starch granules and rice grain quality at the upper (U) and lower panicle. Under D treatment, IR and ZS had lower rice quality, especially the appearance and cooking quality. DHH-U had the highest appearance, nutritional and cooking quality among all cultivars under D treatment, which could be ascribed to the synthesis of more short-branch chain amylopectin and correspondingly higher starch granule tightness. DHH-U also maintained ordered carbohydrate structure, crystalline regions, and many hydrophilic and hydrophobic functional groups in starch granules before pasting. It could prevent the polymerization of small molecules to avoid the formation of macromolecules after pasting. Overall, these findings may facilitate the improvement of grain quality in rice dry cultivation.


Assuntos
Grão Comestível/crescimento & desenvolvimento , Oryza/crescimento & desenvolvimento , Amido/biossíntese , Irrigação Agrícola/métodos , Secas , Grão Comestível/metabolismo , Farinha , Qualidade dos Alimentos , Inflorescência/crescimento & desenvolvimento , Inflorescência/metabolismo , Oryza/metabolismo , Amido/química
8.
Front Nutr ; 8: 758547, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35096925

RESUMO

Taste quality of rice is the key to its value. However, it is greatly affected by rice types and the environment. It is a complex but necessary factor to accurately evaluate the taste quality of various types of rice in different environments. In this study, 7 different types of rice with different taste values were used as materials, and 12 nitrogen fertilizer treatments were applied to obtain 84 different rice taste values. We used protein content, amylose content, and RVA to evaluate changes in the taste value of rice. Rice with high taste value tended to have higher amylose content, peak viscosity, hold viscosity, final viscosity, and breakdown, as well as lower protein content, pasting temperature, and peak time. Protein and amylose contents affected the taste value of rice by affecting the RVA profiles except for setback. For high and low taste-value rice types, protein content could explain 66.8 and 42.9% of the variation in taste value, respectively. In the case of medium taste-value type, protein content was not enough to evaluate the taste quality of rice. Stickiness could explain 59.6% of the variation in taste value. When the protein content of rice was less than 6.61% or greater than 9.34%, it could be used to reflect the taste quality of rice. When the protein content was in between the two, protein content was not enough to reflect the taste quality of rice. Our results suggested that protein content could better reflect the taste quality change for rice, which provided a theoretical and technical basis for the accurate evaluation of the taste value of various types of rice.

9.
Ultrasound Med Biol ; 47(1): 114-124, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33239154

RESUMO

The aim of the work described here was to evaluate the diagnostic performance of ultrasound thyroid computer-aided diagnosis (CAD) software. This multicenter prospective study included 494 patients (565 thyroid nodules) who underwent surgery or biopsy after ultrasonography at four hospitals from January 2019 to September 2019. The diagnostic performance metrics of different readers were calculated and compared with the pathologic results. The sensitivity of CAD was outstanding and was equivalent to that of a senior radiologist (90.51% vs. 88.47%, p > 0.05). The area under the curve of CAD was equivalent to that of a junior radiologist (0.748 vs. 0.739, p > 0.05). However, the specificity was only 49.63%, which was lower than those of the three radiologists (75.56%, 85.93% and 90.37% for the junior, intermediate and senior radiologists, respectively). The diagnostic performance of the junior radiologist was significantly improved with the aid of CAD (junior + CAD). The sensitivity and area under the curve of junior + CAD were improved from 72.20% to 89.93% and from 0.739 to 0.816, respectively (both p values <0.05), and the positive predictive value, negative predictive value and κ coefficient improved from 76.3% to 78.6%, 82.0% to 86.8% and 0.394 to 0.511, respectively. Though specificity slightly decreased from 75.56% to 73.33%, the difference was not statistically significant (p > 0.05). In general, the clinical application value of CAD is promising, and its instrumental value for junior radiologists is significant.


Assuntos
Competência Clínica , Diagnóstico por Computador , Radiologia , Software , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Ultrassonografia
10.
J Sci Food Agric ; 100(2): 595-606, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31591721

RESUMO

BACKGROUND: Climate change has posed great challenges to rice production. Temperature and solar radiation show significant variations in central China. This study aims to analyze the responses of different rice genotypes to the variations of temperature and solar radiation in central China, and to find the way of identifying the optimal sowing date to improve and stabilize rice production. For this end, four rice genotypes (two Indica and two Japonica cultivars) were cultivated at two locations under irrigation conditions in 2 years with six sowing dates. RESULTS: We investigated variations of rice grain yield, resource use efficiency, average daily temperature and solar radiation during different phenological stages. Rice grain yield could increase by about 2-17% in central China. Compared with solar radiation, temperature was a more important factor affecting rice grain yield in central China. The grain yield showed great correlation with the means temperature during different phenological stages, especially during the first 20 days after heading (GT20). Besides our results demonstrated that the grain yield displayed slender variations when the GT20 was within 24.9-26.4 °C. However, GT20 was higher than 26.4 °C in most cases, which became more frequent due to climate changes. Analysis of climate change during the last 25 years revealed that the frequency of GT20 within 24.9-26.4 °C was increased by the delay of sowing date. CONCLUSION: We propose that delaying sowing date to achieve the optimal GT20 (24.9 °C-26.4 °C) can be an effective strategy to stabilize and improve rice grain yield and resource use efficiency in central China. © 2019 Society of Chemical Industry.


Assuntos
Produção Agrícola/métodos , Oryza/crescimento & desenvolvimento , Irrigação Agrícola , China , Mudança Climática , Genótipo , Oryza/genética , Oryza/metabolismo , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Temperatura , Água/análise , Água/metabolismo
11.
ACS Appl Mater Interfaces ; 11(38): 35030-35038, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31487146

RESUMO

Garnet-type solid-state electrolytes (SSEs) show a promising application in solid-state Li batteries. Poor interfacial contact with lithium causing large interfacial impedance and dendrite penetration is a problem. Inspired by unique H+/Li+ exchange of garnet electrolyte, we used an AgNO3 aqueous solution induced strategy to construct a lithiophilic layer in situ on the garnet surface without any specific apparatus. Experimental analysis reveals the uniform distribution of Ag nanoparticles and significantly enhanced affinity between the solid state electrolyte (SSE) and Li anode for the Li-Ag alloying. As expected, the interfacial area specific resistance (ASR) is greatly reduced to ∼4.5 Ω cm2, accompanying with long-cycling stability for ∼3500 h at 0.2 mA cm-2 and high critical current density of 0.75 mA cm-2. With modified SSEs, quasi-solid-state batteries with a LiFePO4 or LiNi0.5Co0.2Mn0.3O2 cathode operate well at room temperature and an all-solid-state LiFePO4/garnet/Li battery displays good cycling stability for over 200 cycles at 60 °C.

12.
Sci Rep ; 9(1): 5351, 2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30926826

RESUMO

Nitrogen (N) and carbon(C) metabolisms in plants were investigated to assess different responses of Bt and non-Bt rice to different N treatments. T2A-1 (Bt rice variety) inserted with Cry2A* protein to resist Lepidoptera and its parental line MH63 was adopted in this study. The total N accumulation presented no statistical difference. But nitrogen contents in different parts of rice plant were significantly different between the two lines, especially on leaf and spike part. This study revealed that the nitrogen in leaf of T2A-1 was far more than that of MH63; however, the nitrogen in spike of T2A-1 was less than that of MH63. In addition, MH63 assimilated more carbon than T2A-1. However, the distribution proportion of carbon in leaf, stem and spike of T2A-1 and MH63 were both 1:1:1. What's more, our study of the difference in metabolism pathway based on proteomics analysis provided more insights on the responses of two lines of Bt and non-Bt rice to different N treatments. And amino acid metabolism, energy metabolism, and carbohydrate metabolism presented significant difference between two lines. In addition, the number of differentially expressed proteins with N deficiency treatment was almost twice as many as that with normal N treatment. It could be inferred that the insertion of Cry2A* in T2A-1 may bring about effects on carbon and nitrogen allocation and related metabolisms, especially under N deficiency environment.


Assuntos
Carbono/metabolismo , Nitrogênio/metabolismo , Oryza/genética , Oryza/metabolismo , Biomassa , Carbono/química , Regulação da Expressão Gênica de Plantas , Nitrogênio/química , Oryza/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas
13.
Ying Yong Sheng Tai Xue Bao ; 21(8): 2010-6, 2010 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-21043109

RESUMO

A field experiment was conducted to study the dynamics of dissolved organic carbon (DOC), readily oxidizable organic carbon (ROC), and microbial biomass carbon (MBC) in a paddy soil under integrated rice-duck farming (RD), intermittent irrigation (RW), and conventional flooded irrigation (CK), the three rice farming modes typical in southern China. Under these three farming modes, the soil DOC and MBC contents reached the highest during the period from rice booting to heading, while the soil ROC content had less change during the whole rice growth period. Two-factor variance analysis showed that soil MBC was greatly affected by rice growth stage, soil DOC was greatly affected by rice growth stage and farming mode, and soil ROC was mainly affected by farming mode. Comparing with CK, RD significantly increased the soil DOC and ROC contents and their availability, while RW significantly decreased the soil DOC content and its availability but increased the soil ROC content and its availability. No significant differences were observed in the soil MBC and microbial quotient among RD, RW, and CK.


Assuntos
Agricultura/métodos , Carbono/análise , Compostos Orgânicos/análise , Oryza/crescimento & desenvolvimento , Solo/análise , Microbiologia do Solo
14.
Ying Yong Sheng Tai Xue Bao ; 20(6): 1375-82, 2009 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-19795647

RESUMO

By using quadratic orthogonal rotation combinatorial design, and taking aluminum (Al), selenium (Se), silicon (Si), and phosphorus (P) as test factors, the regression models of test factors and the survival rate (SR), shoot mass per hundred plants (SMHP), root mass per one hundred plant seedlings (RMHP), and proline contents (PC) of rice seedlings were established, with the individual and interactive effects of the factors analyzed. The individual effects of test factors on the SR, SMHP, RMHP, and PC of rice seedlings decreased in the order of Al > P > Se > Si. Al showed negative effect, while Se, Si, and P showed positive effect. There were no significant interactive effects between the factors, except between Al and Si. Simulated optimization test showed that rice seedlings could grow better in an Al-containing solution when the Al was within the range of 0.587-0.913 mmol L(-1), Se was of 0.478-0.564 mg x L(-1), Si was of 0.613-1.069 mmol x L(-1), and P was of 2.252-2.657 mmol L(-1).


Assuntos
Alumínio/toxicidade , Oryza/crescimento & desenvolvimento , Fósforo/farmacologia , Plântula/crescimento & desenvolvimento , Selênio/farmacologia , Alumínio/farmacologia , Interações Medicamentosas , Modelos Teóricos , Oryza/efeitos dos fármacos , Plântula/efeitos dos fármacos , Silício/farmacologia
15.
Ying Yong Sheng Tai Xue Bao ; 17(10): 1859-65, 2006 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-17209383

RESUMO

With hybrid rice cultivar Liangyou Peijiu as test material, this paper studied its biological characteristics and water use efficiency under effects of four irrigation modes. Compared with continuous flooding irrigation, intermittent irrigation increased the leaf area index, photosynthetic rate and water use efficiency, and decreased the leaf transpiration rate. Semi-dry cultivation increased the leaf water use efficiency, while dry cultivation decreased the leaf area index, photosynthetic rate, and water use efficiency, and induced the leaf senescence in later growth period. Under intermittent irrigation, semi-dry cultivation and dry cultivation, the water consumption of paddy rice was 8. 75% , 17. 96% and 29. 69% lower, and its grain yield was 24. 02% higher but 5. 07% and 38. 93% lower than that under continuous flooding irrigation, respectively. The water use efficiency was the highest under intermittent irrigation, relatively high under semi-dry cultivation, but relatively low under continuous flooding irrigation and dry cultivation. Compared with other irrigation modes, intermittent irrigation increased the milled rice rate, head rice rate and grain length, while decreased the chalky rice and chalkiness. With the reduction of water consumption, the amylose content of rice grain decreased, but the gel consistency and protein content increased. Intermittent irrigation could be a favorable irrigation mode for the paddy rice planting in Southern China.


Assuntos
Agricultura/métodos , Oryza/fisiologia , Transpiração Vegetal/fisiologia , Cruzamentos Genéticos , Hibridização Genética , Oryza/genética , Oryza/metabolismo , Fotossíntese/fisiologia , Água/metabolismo
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