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1.
Ying Yong Sheng Tai Xue Bao ; 34(6): 1541-1546, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37694416

RESUMO

The development of precise climate risk zoning for chilling injury of Morchella esculenta can provide scientific basis for agricultural cultivation planning, dynamic assessment of chilling injury, and disaster prevention strategies. Based on meteorological data from 17 counties (cities) that located below the altitude of 3000 m in the Western Sichuan Plateau from 2011 to 2020, we analyzed the critical meteorological conditions for M. esculenta disasters in typical years. With the average yearly cold accumulation and cold injury frequency during the first day when the temperature remained stable between 5 ℃ and 10 ℃ during mushroom emergence as zoning indicators, we established a geographical spatial distribution model of the cold injury index, and then divided the risk level of M. esculenta cold injury in the Western Sichuan Plateau, evaluated the risk of cold injury. The results showed that the temperature index for chilling injury risk of M. esculenta in the study area was the daily minimum temperature ≤2.0 ℃. The daily average temperature <6.0 ℃ would cause slow growth or the cessation of growth, which was set as a warning indicator for chilling injury risk. Along the Dadu River and Minjiang River basins, the frequency of chilling injury on M. esculenta increased from south to north. Wenchuan, Maoxian, and Lixian had the fewest overall chilling injuries during the study period, whereas Jiulong, Yajiang, and Batang had the most. The duration for cold injury was mainly 1-3 d, followed by 4-5 d, and rarely for >5 d. The frequency of chilling injury lasting for more than 5 d in Xiangcheng, Batang, Jiulong, Yajiang, and Xiaojin was more than that lasting for 4-5 d. The annual average days of chilling injury of was 3.0-27.4 d, the daily average minimum temperature was -0.84-1.36 ℃, the extreme lowest temperature was -5.8-0.1 ℃, and the average accumulated cold was 0.16-9.64 ℃·d during the period of chilling injury. With the increases of elevation and latitude, the average days of chilling injury and the average accumulated cold increased. The largest duration of chilling injury was 3-20 d, the maximum accumulated cold was 0.44-13.34 ℃·d. The risk of chilling injury to M. esculenta increased from south to north and from low elevation to high elevation. The suitable planting areas were distributed in strips and branches along the direction of mountains and rivers, mainly in the flat areas of low mountains and valleys below the altitude of 2200 m, including Kangding, Luding, Danba, Wenchuan, Lixian, Maoxian, Jiuzhaigou, and Songpan.


Assuntos
Lesão por Frio , Temperatura Baixa , Humanos , China , Medição de Risco
2.
Polymers (Basel) ; 14(7)2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35406346

RESUMO

To study the behavior of square concrete-filled CFRP (carbon fiber polymer) steel tubular under bending-torsional load, nine square section concrete-filled CFRP steel tubular specimens are designed. The T-θ curve and failure mode of square concrete-filled CFRP steel tubular are studied under a bending-torsional load. Based on the test results, a finite element modeling method is proposed by using the finite element software ABAQUS, and the simulation results are compared with the experimental results. The results show that the simulation is in good agreement with the experimental results. On the basis of verifying the reliability of the model, the whole stress process and parameter analysis of the component are studied, and the calculation expression of bearing capacity of square concrete-filled CFRP steel tubular under bending-torsion load is proposed. The predicted specimen-bearing capacity of the proposed calculation expression of the bearing capacity of square concrete-filled CFRP steel tubular under bending-torsion load is basically consistent with the test results.

3.
Zhongguo Zhong Yao Za Zhi ; 47(23): 6529-6532, 2022 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-36604900

RESUMO

According to Provisions for Drug Registration and Categories and Requirements of Application Dossiers for Traditional Chinese Medicine(TCM), non-clinical safety research/toxicology research should be conducted for classical compound Chinese medicine prescriptions(Categories 3.1 and 3.2), and the data should be submitted at the application for the marketing authorization. Based on the requirements of toxicology research in Categories and Requirements of Application Dossiers for Traditional Chinese Medicine, this study further refined and clarified the requirements of toxicology research on classical compound Chinese medicine preparations(Categories 3.1 and 3.2).


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Medicamentos de Ervas Chinesas/toxicidade , Prescrições , Prescrições de Medicamentos
4.
Ying Yong Sheng Tai Xue Bao ; 32(7): 2525-2533, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34313071

RESUMO

Based on the distribution data of Tricholoma matsutake obtained from field investigation and literature, the ecological-niche factor analysis (ENFA) and the maximum entropy model (MaxEnt) were used to simulate the distribution law and suitable area of T. matsutake in the western Sichuan Plateau. The prediction was made for the future changes in the suitable area of T. matsutake by analyzing the relationship between climate factors and dynamic distribution. The results showed that the area under curve (AUC) values of both the model training set and validation set were greater than 0.90, indicating that the model prediction results were extremely accurate. The environmental variables affecting the potential distribution of T. matsutake were mainly the lowest temperature in the coldest month, the coldest season precipitation, annual temperature difference and soil type, with accumulative contribution of 90.3%. The niche parameters of suitable distribution areas of T. matsutake were as follows: the lowest temperature in the coldest month was -18.5--5.4 ℃, the coldest season precipitation was less than 15.7 mm, the annual temperature difference was 39.5-45 ℃, and soil type was semi-leached soil, including dry red soil, cinnamon soil, gray cinnamon soil, black soil and grey forest soil. The suitable areas of T. matsutake were distributed in the southwest, south, central and east of the plateau at an altitude range of 1900-3600 m. The highly suita-ble areas were mainly distributed in some towns of Yajiang, Xiangcheng, Kangding, Jiulong, Daocheng, Litang, Batang, Danba, Maerkang, Xiaojin, Jinchuan, Lixian, Maoxian, etc. The moderately and lowly suitable areas were located in some towns of Derong, Daofu, Xinlong, Luhuo, Baiyu, Luding, Rangtang, Wenchuan, Heishui, Jiuzhaigou. The highly suitable areas were discontinuously distributed according to the direction of rivers and mountains. The moderately suitable areas were connected with the highly suitable areas, while the lowly suitable areas were the extension of the highly and moderately suitable areas. Future climate change would be beneficial to the growth of T. matsutake on the western Sichuan Plateau, while the climate-suitable areas would show an overall increasing trend. Suitable areas in the low-altitude Minjiang River Basin would be more affected by climate change than those located in high-altitude areas.


Assuntos
Tricholoma , Agaricales , China , Mudança Climática , Ecossistema
5.
Artigo em Inglês | MEDLINE | ID: mdl-31677481

RESUMO

Amino acids play key roles in cellular protein biosynthesis and energy metabolism pathways. In this study, a simple, rapid and sensitive method was developed for the simultaneous determination of 24 free amino acids in cell samples using hydrophilic interaction liquid chromatography coupled to tandem mass spectrometry (HILIC-MS/MS). Cell samples were deproteinized with methanol/H2O (80:20, v/v) without intricate derivatization process. The analytes were separated on a Waters BEH Amide column (2.1 mm × 100 mm, 1.7 µm), and accomplished within 5 min at a flow rate of 0.2 mL/min. The good linearity was obtained for all analytes (r2 > 0.99) with the limits of quantification from 0.1 to 25 ng/mL. The intra- and inter-day precision ranged from 0.35 to 10.36% and from 2.22 to 9.93%, respectively. The recoveries of most analytes were between 80% and 120% with RSD less than 10.0%. The developed method was then applied to the direct analysis of 24 underivatized amino acids in human gastric cancer cell line MGC803 treated with the antitumor candidate drug J3, and significant differences in the concentration levels of amino acids were also assessed.


Assuntos
Aminoácidos/análise , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Linhagem Celular Tumoral , Humanos , Interações Hidrofóbicas e Hidrofílicas , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Ying Yong Sheng Tai Xue Bao ; 30(7): 2137-2144, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31418215

RESUMO

Based on the biological characteristics of Cordyceps sinensis, combined with the spatial and temporal distribution characteristics of local agro-climatic resources and the investigation data of C. sinensis resources, we investigated the ecological climate suitability regionalization and the spatial distribution of C. sinensis in Shiqu County using mathematical statistics analysis, optimization method and GIS spatial analysis. We used altitude, mean annual temperature, mean annual precipitation, vegetation, and soil as the leading indicators and topographic gradient as the auxiliary indicators, as the main basis for the suitability zoning of C. sinensis resources. The results showed that C. sinensis grew in most of the townships in Shiqu County, with their distribution areas being fragmented and scattered, showing sporadic patches and blocks. They were mainly distributed in east and west parts of the county and in the Zhaqu River basin in the central part. The suitable distribution area for C. sinensis in Shiqu was 4000-4700 m above sea level, with mean annual temperature of -2.5-3 ℃ and mean annual precipitation of 550-850 mm. The growth environment was generally alpine mea-dow and subalpine meadow with good hydrophobicity and slope of 15°-50°. The suitable growth environment and meteorological conditions were beneficial to the growth and development of feeding plants and bat moths. The unsuitable area was in the high mountain area above the river wide valley area, pastoral area, wetland, or snowline.


Assuntos
Cordyceps , Sistemas de Informação Geográfica , China , Clima , Ecologia , Solo
7.
J Asian Nat Prod Res ; 21(5): 476-493, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-29322879

RESUMO

Diabetic cardiomyopathy (DCM) is one of the chief diabetes mellitus complications. Inflammation factors may be one reason for the damage from DM. The purpose of this research is to study the potential protective effects of puerarin on DM and the possible mechanisms of action related to NF-κB signal pathway. Following administration of puerarin to the disease model rat, several changes were observed including the changes of serum biochemical index, improved diastolic dysfunction, and enhanced endogenous antioxidant enzymes activities, further NF-κB signaling activation. Puerarin showed cardio-protective effects on DCM by inhibiting inflammation, and it might be a potential candidate for the treatment of DCM.


Assuntos
Diabetes Mellitus Experimental/complicações , Cardiomiopatias Diabéticas/prevenção & controle , Inflamação/tratamento farmacológico , Isoflavonas/farmacologia , Animais , Linhagem Celular , Células Cultivadas , Glucose/toxicidade , Isoflavonas/química , Estrutura Molecular , Mioblastos Cardíacos/efeitos dos fármacos , Miocárdio/citologia , NF-kappa B , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
8.
Pediatr Neurol ; 61: 63-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27265460

RESUMO

BACKGROUND: Congenital insensitivity to pain with anhidrosis is an extremely rare hereditary disorder linked to variants in NTRK1. Our goal was to characterize the clinical features and the genetic basis of the disorder in Chinese patients. METHODS: Patients were enrolled via social networking. Clinical features were investigated by interview, chart review, and physical examination. DNA was extracted from peripheral blood to genotype NTRK1 in patients and their parents. Variants identified were checked against a control cohort by high-throughput sequencing, and the effects of these variants were assessed in silico. RESULTS: Clinical features in five patients were cataloged, and six loss-of-function NTRK1 variants were identified, including a frameshift variant c.963delG, a nonsense variant c.1804C>T, an intron variant c.851-33T>A, and three missense variants c.1802T>G, c.2074C>T, and c.2311C>T. CONCLUSIONS: The results expand the spectrum of clinical and genetic features of congenital insensitivity to pain with anhidrosis and will help facilitate analysis of genotype-phenotype association in the future.


Assuntos
Neuropatias Hereditárias Sensoriais e Autônomas/genética , Neuropatias Hereditárias Sensoriais e Autônomas/fisiopatologia , Receptor trkA/genética , Criança , Pré-Escolar , Feminino , Genótipo , Humanos , Mutação com Perda de Função , Masculino , Fenótipo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Adulto Jovem
9.
Biomed Res Int ; 2016: 9025643, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28044138

RESUMO

Background. Patients' and family's satisfaction data from the Asian intensive care units (ICUs) is lacking. Objective. Domains between patient and family satisfaction and contribution of each domain to the general satisfaction were studied. Method. Over 3 months, adult patients across 4 ICUs staying for more than 48 hours with abbreviated mental test score of 7 or above and able to understand English and immediate family members were surveyed by separate validated satisfaction questionnaires. Results. Two hundred patients and 194 families were included in the final analysis. Significant difference in the satisfaction scores was observed between the ICUs. Patients were most and least satisfied in the communication (4.2 out of 5) and decision-making (2.9 out of 5) domains, respectively. Families were most and least satisfied in the relationship with doctors (3.9 out of 5) and family's involvement domains (3.3 out of 5), respectively. Domains contributing most to the general satisfaction were the illness management domain for patients (ß coefficient = 0.44) and characteristics of doctors and nurses domain for family (ß coefficient = 0.45). Discussion. In an Asian ICU community, patients and families differ in their expectations and valuations of health care processes. Health care providers have difficult tasks in attending to these different domains.


Assuntos
Cuidados Críticos/psicologia , Família/psicologia , Unidades de Terapia Intensiva/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Comunicação , Estudos Transversais , Tomada de Decisões/fisiologia , Feminino , Pessoal de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Enfermeiras e Enfermeiros , Satisfação Pessoal , Médicos , Inquéritos e Questionários , Adulto Jovem
10.
Yao Xue Xue Bao ; 51(8): 1185-95, 2016 08.
Artigo em Chinês | MEDLINE | ID: mdl-29897711

RESUMO

Alzheimer's disease(AD) is a chronic progressive neurodegenerative disease. The pathogenesis of AD is unclear, and it is presently incurable. Medicines currently available for AD treatment are only for improving the cognitive symptoms, but not able to stop or delay disease progression. Here, we summarized the interventions in early phases of AD in clinical trial. As a complex disease, AD is difficult to be restored through a treatment on a single target. Multi-target and cocktail drugs might be a strategy for development of AD therapies. In addition, AD is characterized by progressive neuronal loss in the cortex and hippocampus. The induction of neurogenesis by small molecule compounds has drawn attention in the AD field. The study of natural products in China is leading the way in the AD world. Numerous natural products have been identified for pharmacological effects on multi-targets in the regulation of neurogenic activity, which may open up a new avenue for AD treatments.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Produtos Biológicos/uso terapêutico , China , Ensaios Clínicos como Assunto , Progressão da Doença , Humanos , Neurogênese
11.
Int J Clin Exp Med ; 8(4): 6103-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26131211

RESUMO

AIM: The aim of this study is to assess the effects of hydrosalpinx on ultrasonographic parameters for endometrial receptivity during the window of implantation, as measured by power color Doppler ultrasound. METHODS: The women recruited to this study included sixty with unilateral or bilateral hydrosalpinx and fifty-seven prior to in vitro fertilization-embryo transfer (IVF-ET) or artificial insemination (AI) performed due to male infertility. Ultrasonographic parameters for endometrial receptivity were measured during the window of implantation by power color Doppler ultrasound. RESULTS: The proportion of triple-line endometrial pattern and uterine contractions from the cervix to the fundus were significantly lower in the hydrosalpinx group than in the control group. In addition, patients in the hydrosalpinx group had a significantly lower pulsatility index (PI) of uterine spiral arteries. There were no significant differences in endometrial thickness, subendometrial blood flow distribution pattern, uterine artery PI, uterine artery resistance index (RI), or uterine spiral artery RI between the two groups. CONCLUSIONS: Hydrosalpinx may be involved in the regulation of endometrial receptivity through its influence on endometrial pattern, uterine contractions, and PI of the uterine spiral arteries.

12.
Ying Yong Sheng Tai Xue Bao ; 24(1): 10-6, 2013 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-23717984

RESUMO

A sampling plot investigation was conducted to study the soil organic carbon (SOC) storage in 0-40 cm layer in 10-, 15-, 26- and 61 years old Larix gmelinii plantations in Great Xing' an Mountains of Northeast China as well as the temporal variation pattern of the SOC source/sink during the plantation management after the clear cutting of primary L. gmelinii forest. With the increasing age of the plantations, the SOC storage increased after an initial decrease, and the inflection point was at a stand age between 15- and 26-years old. Compared with that of primary forest, the SOC storage of the plantations played a role of carbon source at early stage (10-26 years old), but gradually transformed into carbon sink then, with a SOC storage of 158.91 t x hm(-2) in 61-year-old plantation. The SOC storage of the plantations increased with soil depth initially, but was higher in upper soil layer than in deeper soil layer after the stand age being 26, which implied that human disturbance had strong effects on the vertical distribution of SOC. It was considered that the appropriate cutting age for the L. gmelinii plantations in Great Xing' an Mountains could be at least 60 years old.


Assuntos
Carbono/análise , Larix/crescimento & desenvolvimento , Compostos Orgânicos/análise , Solo/química , China , Ecossistema , Fatores de Tempo
13.
Artigo em Chinês | MEDLINE | ID: mdl-23072146

RESUMO

The killing effect of different concentrations of garlic extract solution on Schistosoma japonicum cercariae and Oncomelania snails was observed under dissecting microscope. Mice were infected by cercariae through the abdominal skin daubed by garlic solution or by deionized water as control. The results showed that the cercariae were killed in (77.33 +/- 25.01) s in average, it needed (73.00 +/- 1.73)- (299.67 +/- 18.96) s under the garlic solution concentrations of 50.00%-0.79% respectively, while the cercariae kept alive in 600 s in the control. The snails were killed in 1 d by 100% garlic solution but no death in the control in 2 d. No mouse daubed with different concentrations of garlic solution was found infected by schistosomes while 100% of the control mice got infected. It is concluded that the garlic shows satisfactory effect in killing cercariae and Oncomelania snails, and may prevent schistosome infection by daubing the skin.


Assuntos
Cercárias/efeitos dos fármacos , Alho/química , Extratos Vegetais/farmacologia , Schistosoma japonicum/efeitos dos fármacos , Caramujos/efeitos dos fármacos , Animais , Camundongos , Esquistossomose Japônica
14.
Naunyn Schmiedebergs Arch Pharmacol ; 385(6): 579-85, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22447151

RESUMO

The aim of this study was to investigate the protective effects of N-[2-(4-hydroxy-phenyl)-ethyl]-2-(2,5-dimethoxy-phenyl)-3-(3-methoxy-4-hydroxy-phenyl)-acrylamide (FLZ), a synthetic squamosamide cyclic derivative, on senescent mice induced by D: -galactose/NaNO(2) (120/90 mg/kg, i.p.) once daily for 60 days. FLZ (75 and 150 mg/kg) was orally administered once daily for 30 days after D: -galactose/NaNO(2) treatment for 30 days. The cognitive function of mice was evaluated with step-down task. The brain biomarkers including monoamine oxidase B (MAO-B), glutathione peroxidase (GSH-px), and malondialdehyde (MDA) were determined according to the manufacturer's instructions. The expression of acetylcholinesterase (ACh-E) and choline acetyltransferase (ChAT) protein in the CA1 region of hippocampus were counted by immunohistochemical staining. The results showed that the cognitive function, GSH-px activity in the brain, and the expression of ACh-E and ChAT in the CA1 region of hippocampus were significantly decreased, while MAO-B activity and MDA level in the brain were increased in senescent mice compared with the control mice. FLZ treatment prolonged the step-down latency and decreased the number of step-down errors in the senescent mice. In addition, FLZ treatment increased the GSH-px activity and the expression of ACh-E and ChAT in the hippocampus and decreased the MDA level and MAO-B activity compared with the senescent mice without drug administration. These findings suggested that FLZ improves the performance in the step-down task and the pathological alternations in senescent mice.


Assuntos
Envelhecimento/fisiologia , Benzenoacetamidas/uso terapêutico , Transtornos da Memória/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Fenóis/uso terapêutico , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Benzenoacetamidas/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Galactose , Glutationa Peroxidase/metabolismo , Masculino , Malondialdeído/metabolismo , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/fisiopatologia , Camundongos , Camundongos Endogâmicos ICR , Monoaminoxidase/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , Fenóis/farmacologia , Nitrito de Sódio
15.
Ying Yong Sheng Tai Xue Bao ; 22(2): 273-9, 2011 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-21608236

RESUMO

Through sampling site investigation, this paper studied the carbon storage of arbor, herb, and whole vegetation in 10-, 12-, 15-, 26-, and 61-year old Larix gmelinii plantations in Huzhong Forestry Bureau of Great Xing' an Mountains, Northeast China, and 'temporal for spatial' method was employed to approach the variations of the vegetation carbon storage during the growth of the plantations. The results revealed that the vegetation carbon storage in the plantations increased with stand age, and reached 105.69 t x hm(-2) at age of 61 years, representing a marked role as a carbon sink. The L. gmelinii plantations at the ages from 15 to 26 years had the strongest capability in carbon sequestration, in which, the carbon storage in trunk occupied 54.3% -73.9% of the total carbon storage of arbor, and, with the increase of stand age, the trunk's carbon storage to the total carbon storage of arbor as well as the trunk's carbon density increased. As for the other organs, the rate of their carbon storage to the total carbon storage of arbor decreased with stand age, while their carbon density increased first but eventually leveled off or had a slight decrease till at age of 61 years. Based on these results, the rotation age for the L. gmelinii plantations in Great Xing' an Mountains would properly be lengthened to at least 60 years.


Assuntos
Dióxido de Carbono/metabolismo , Carbono/análise , Larix/crescimento & desenvolvimento , Larix/metabolismo , Caules de Planta/metabolismo , Biomassa , China
16.
Ying Yong Sheng Tai Xue Bao ; 19(1): 20-4, 2008 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-18419066

RESUMO

Based on Digital Elevation Models (DEM) and satellite SPOT-5 data, and by using the spatial analysis function in Geographic Information System, a hierachical Ecological Classification System of forest landscape was developed for the eastern mountainous region of Liaoning Province, and the two lowest layers in the hierachical framework, Ecological Land Types (ELTs) and Ecological Land Type Phases (ELTPs), were mapped. The results indicated that there were 5 ELTs and 34 ELTPs. The boundaries of ELTs, which presented the potential vegetation distribution and potential forestry ecosystem productivity, were determined by environmental conditions quantified by DEM. ELTPs were classified by overlaying ELTs with forest vegetation data layers which were obtained from remotely sensed data, forest inventory data, and ground data. The ELTPs represented the divisions of land in terms of both natural and human-induced forest conditions, and therefore, were reliable units for forest inventories and management. ELTPs could function as conventional forest inventory sub-compartments. By this means, forestry departments could adjust forest management planning and forest management measures from the viewpoint of forest landscape scale to realize forest ecosystem management.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Planejamento Ambiental , Árvores/crescimento & desenvolvimento , Altitude , China , Ecologia/métodos , Monitoramento Ambiental , Sistemas de Informação Geográfica , Geografia , Comunicações Via Satélite , Árvores/classificação
17.
World J Gastroenterol ; 12(14): 2284-7, 2006 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-16610038

RESUMO

AIM: To investigate the effect of firing noise on gastrointestinal transit and probe its mechanism by measuring the levels of plasma polypeptide hormones. METHODS: A total of 64 SD rats were randomly divided into a control group and three stimulating groups. Firing noise of different intensity by sub-machine guns was used as inflicting factor. The effect of firing noise on liquid substance gastrointestinal transit and solid substance gastrointestinal transit was observed by measuring the ratio of carbon powder suspension transmitting and barium sticks transmitting respectively. Plasma levels of polypeptide hormones were measured by radio-immunoassay. RESULTS: The noise accelerated gastrointestinal transit of solid food by more than 80 db;and accelerated gastrointestinal transit of liquid food significantly by more than 120 db. Meantime, plasma levels of plasma motilin (MTL)(157.47+/-16.08; 151.90+/-17.08), somatostatin (SS)(513.97+/-88.77; 458.25+/-104.30), substance P (SP)(115.52+/-20.70; 110.28+/-19.96) and vasoactive intestinal peptide (VIP) (214.21+/-63.17; 251.76+/-97.24) remarkably changed also. CONCLUSION: Within a certain intensity range, the firing noise changes the levels of rat plasma gastrointestinal hormones, but the gastrointestinal transit is still normal. Beyond the range, the noise induces plasma hormone levels disturbance and gastrointestinal transit disorder.


Assuntos
Hormônios Gastrointestinais/sangue , Trânsito Gastrointestinal , Ruído , Hormônios Peptídicos/sangue , Animais , Explosões , Ratos , Ratos Sprague-Dawley
18.
J Environ Sci (China) ; 15(2): 182-6, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12765259

RESUMO

Boundaries between different forest types in Changbai Mountain Eastern China are results from complex interactions between forest ecosystems, topography, and geomorphology. Detecting and quantifying the transitional zones are highly important since high environmental heterogeneity and biodiversity are often found within these zones. In this study, we used GIS and multivariate statistics techniques (PCA and MSWA) to analyze data from Landsat TM satellite imageries and quantitatively determined the positions and widths of the landscape boundary between mountain birch and evergreen coniferous forests in the northern slope of Changbai Mountain. The results showed that the widths of the landscape boundary ranges from 30-50 m while using the MSWA or/and PC method. Such detected widths are consistent with field transect data that suggests a 50 m transitional zone width. The results further suggest that TM data can be used in combination with GIS and statistical techniques in determining forest landscape boundaries; MSWA is more reliable than PCA, while PCA can also be used to determine the landscape boundary when transects are properly located.


Assuntos
Betula/fisiologia , Ecossistema , Traqueófitas/fisiologia , Árvores/fisiologia , Altitude , China , Geografia , Humanos , Modelos Estatísticos , Comunicações Via Satélite
20.
World J Gastroenterol ; 4(6): 519-523, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11819360

RESUMO

AIM:To establish an experimental model of stress ulcer produced by explosive noise, and to probe into its mechanism and protection.METHODS:The country standard Wistar white rats were randomly divided into control group(n =8), which were neither stimulated nor protected, and stimulating group (divided into subgroups A, B and C, including 8 rats each which were decapitated to draw blood for test immediately, 12 hours and 24 hours after stimulation) and prevention group (divided into subgroups A, B and C, having 8 rats each, subgroup A was given cimetidine, B anisodamine and C both drugs). Firing noises of submachine guns were used as inflicting factor. The rats were fasted for 24 hours and stimulated by firing noise for 12 hours. The change of ulcer index, gastric mucosal and related serum hormones were observed.RESULTS:Stress ulcer was significant in the stimulating group, and its ulcer index (8.6 ± 0.6) was remarkably higher than that in both the control group and prevention group (0.3 ± 0.1, P < 0.01).Its serum gastrin (Gas ng/L, 294 ± 163 vs 63 ± 40,P< 0.01) and endothelin (ET ng/L, 181 ± 57 vs 135 ± 42, P < 0.1) were apparently higher than those in the control group, and its serum nitric oxide (NO) level was conspicuously lower than that in the control group (ng/L, 0.3 ± 0.1 vs 0.8 ± 0.5 P <0.5), while the serum gastrin level (ng/L, 556 ± 225) in prevention group was distinctly higher than that in both the control (P<0.1) and stimulating group (P < 0.5). There were no significant differences in the changes of ET and NO between the control and the stimulating groups.CONCLUSION:Stress ulcer model of rats can be successfully established by the stimulation of explosive noise. Gas, ET and NO are related to the formation of stress ulcer, and play an important role in its mechanism. Hepatic function affected by noise is observed in this experiment.

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