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Environmental factors influencing the distribution of total and fecal coliform bacteria in six water storage reservoirs in the Pearl River Delta Region,China 被引量:9
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作者 Huachang Hong Jianwen Qiu Yan Liang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第5期663-668,共6页
The Pearl River Delta (PRD) is one of the most developed and densely populated regions in China.Quantifying the amount of pathogens in the source of drinking water is important for improving water quality.We collect... The Pearl River Delta (PRD) is one of the most developed and densely populated regions in China.Quantifying the amount of pathogens in the source of drinking water is important for improving water quality.We collected water samples from six major water storage reservoirs in the PRD region in both wet and dry seasons in 2006.Results showed that external environmental factors,such as precipitation,location,as well as the internal environmental factors,i.e.,physicochemical properties of the water,were closely related with the distribution of coliforms.Seasonally,the coliform bacterial concentrations in wet season were one to two orders of magnitude greater than those in dry season.Spatially,coliform bacterial levels in reservoirs near urban and industrial areas were significantly higher (p 〈 0.05) than those in remote areas.Correlation analyses showed that the levels of coliforms had close relationships with pH,temperature,suspended solid,organic and inorganic nutrients in water.Principal components analysis further demonstrated that total coliforms in the reservoirs were closely related with water physicochemical properties,while fecal coliforms were more associated with external input brought in by seasonal runoff. 展开更多
关键词 coliform bacteria location RAINFALL physicochemical parameters RESERVOIR
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DNA Damage after Ozone-Photodynamic Therapy in Cancer Animals: Experimental Research 被引量:1
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作者 Shcherbatyuk Tatiana,G Chemigina Irina,A +1 位作者 Plekhanova Evgeniya,S Shakhov Boris, E. 《Journal of Pharmacy and Pharmacology》 2017年第8期497-505,共9页
Objectives: To assess the genotoxic effect of a new antitumor ozone-photodynamic therapy using the improvedmodification of the COMET assay. Methods: Xenograft cancer models on 58 rats were used. The sarcoma RA was t... Objectives: To assess the genotoxic effect of a new antitumor ozone-photodynamic therapy using the improvedmodification of the COMET assay. Methods: Xenograft cancer models on 58 rats were used. The sarcoma RA was transplantedsubcutaneously, and after increasing of tumor volume from 0.5 to 4.2 cm3, rats were divided into the four groups: "Intact"--healthy,"Control"--with xenografted tumors and no treatment, "PDT"--the rats treated with the photodynamic therapy, "PDT +ozone"--the rats were treated with both photodynamic therapy and injections of ozonated saline solution. The toxicity of treatmentwas assessed by DNA damage in leukocytes using the new modification of the COMET assay. The analysis of the "COMETs" wasperformed following the percentage of DNA in the tail of the "COMET" (% TDNA). Results: A combination of PDT and ozonemakes the strongest negative impact on tumor growth. The tumor growth inhibition is associated with low genotoxic exposure ofozone-photodynamic therapy on whole blood leukocytes of cancer rats. Conclusions: A new modification of the COMET assay canprovide the assessment of the genotoxic effect of the antitumor therapy in experimental neoplasia. 展开更多
关键词 COMET assay DNA damage ozonetherapy photodynamic therapy experimental neoplasia.
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Do Really Close Stomata by Soil Drying ABA Produced in the Roots and Transported in Transpiration Stream?
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作者 Joon Sang Lee 《American Journal of Plant Sciences》 2013年第1期169-173,共5页
Stomatal aperture responses of Commelina communis L. between well watered plants and water stressed plants were investigated. To see the very rapid response to water stress, the plants were directly rooted out from th... Stomatal aperture responses of Commelina communis L. between well watered plants and water stressed plants were investigated. To see the very rapid response to water stress, the plants were directly rooted out from the soil and exposed to the air immediately. Stomata, rooted out from the soil, were totally closed within 10 minutes without any detention time while the stomata of the plants in the soil had been kept opening. These results suggest that stomatal response to the abrupt water stress is very rapid indicating that guard cell itself or leaves could sense water status in the plants. 展开更多
关键词 Abscisic Acid COMMELINA communis L. Signal TRANSDUCTION Pathway Water Stress
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Infant Cry Language Analysis and Recognition:An Experimental Approach 被引量:2
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作者 Lichuan Liu Wei Li +1 位作者 Xianwen Wu Benjamin X.Zhou 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第3期778-788,共11页
Recently, lots of research has been directed towards natural language processing. However, the baby's cry, which serves as the primary means of communication for infants, has not yet been extensively explored, bec... Recently, lots of research has been directed towards natural language processing. However, the baby's cry, which serves as the primary means of communication for infants, has not yet been extensively explored, because it is not a language that can be easily understood. Since cry signals carry information about a babies' wellbeing and can be understood by experienced parents and experts to an extent, recognition and analysis of an infant's cry is not only possible, but also has profound medical and societal applications. In this paper, we obtain and analyze audio features of infant cry signals in time and frequency domains.Based on the related features, we can classify given cry signals to specific cry meanings for cry language recognition. Features extracted from audio feature space include linear predictive coding(LPC), linear predictive cepstral coefficients(LPCC),Bark frequency cepstral coefficients(BFCC), and Mel frequency cepstral coefficients(MFCC). Compressed sensing technique was used for classification and practical data were used to design and verify the proposed approaches. Experiments show that the proposed infant cry recognition approaches offer accurate and promising results. 展开更多
关键词 Compressed sensing FEATURE extraction INFANT CRY signal LANGUAGE RECOGNITION
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Double-stranded DNA breaks and gene functions in recombination and meiosis 被引量:1
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作者 Wuxing Li Hong Ma 《Cell Research》 SCIE CAS CSCD 2006年第5期402-412,共11页
Meiotic prophase I is a long and complex phase. Homologous recombination is an important process that occurs between homologous chromosomes during meiotic prophase I. Formation of chiasmata, which hold homologous chro... Meiotic prophase I is a long and complex phase. Homologous recombination is an important process that occurs between homologous chromosomes during meiotic prophase I. Formation of chiasmata, which hold homologous chromosomes together until the metaphase I to anaphase I transition, is critical for proper chromosome segregation. Recent studies have suggested that the SPO 11 proteins have conserved functions in a number of organisms in generating sites of double-stranded DNA breaks (DSBs) that are thought to be the starting points of homologous recombination. Processing of these sites of DSBs requires the function of RecA homologs, such as RAD5 1, DMC 1, and others, as suggested by mutant studies; thus the failure to repair these meiotic DSBs results in abnormal chromosomal alternations, leading to disrupted meiosis. Recent discoveries on the functions of these RecA homologs have improved the understanding of the mechanisms underlying meiotic homologous recombination. 展开更多
关键词 MEIOSIS homologous recombination double-stranded DNA breaks SPO11 RAD51 DMC 1
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Multiple Sclerosis and Treatment: Drug Management and Nutrition with Exercise
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作者 Hector Melissinos 《Journal of Pharmacy and Pharmacology》 2017年第12期921-927,共7页
MS (multiple sclerosis) is a chronic inflammatory disease of the CNS (central nervous system), characterized by the degeneration of the insulating caps of the brain and spinal nerve cells. Most axons are surrounde... MS (multiple sclerosis) is a chronic inflammatory disease of the CNS (central nervous system), characterized by the degeneration of the insulating caps of the brain and spinal nerve cells. Most axons are surrounded by an insulating lipoprotein, myelin, which helps in the transmission of nerve impulses. Myelin destruction disrupts the ability of parts of the nervous system to communicate, resulting in a wide range of symptoms, including physical, mental, and sometimes psychiatric problems. Multiple sclerosis affects more than 2.1 million people worldwide, but its incidence has increased in the last five decades among young people and women, with a 3:1 ratio compared to men. Latitude is associated with a variety of environmental factors, most notably exposure to solar radiation. The risk of developing MS is inversely proportional to solar exposure and vitamin D, particularly the 1,25-(OH)2D3 derivative that has anti-inflammatory and immunomodulatory activity, is probably the responsible protective agent. There are various therapies that are targeting the treatment of the disease, yet MS is considered an uncurable disease. Available medicines are aimed at relieving symptoms and improving the progression of the disease. In the present study, we will present the disease with reference to the pathogenesis and epidemiology of the disease. We will analyze the environmental factors that influence the development by reference to the etiology and pathophysiology, as well as reference to existing therapies. The ultimate aim of this study is to examine to what extent physical exercise and nutrition, in conjunction with pharmaceutical treatments and mainly intake of vitamin D, can contribute drastically to the fight against the disease and at the same time improve areas that make up the quality of life of the patient. 展开更多
关键词 MS CNS MYELIN etiology and pathophysiology of MS vitamin D and MS.
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Adaptive hearing in the vocal plainfin midshipman fish:getting in tune for the breeding season and implications for acoustic communication
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作者 Joseph A.SISNEROS 《Integrative Zoology》 SCIE CSCD 2009年第1期33-42,共10页
The plainfin midshipman fish(Porichthys notatus Girard,1854)is a vocal species of batrachoidid fish that gen-erates acoustic signals for intraspecific communication during social and reproductive activity and has beco... The plainfin midshipman fish(Porichthys notatus Girard,1854)is a vocal species of batrachoidid fish that gen-erates acoustic signals for intraspecific communication during social and reproductive activity and has become a good model for investigating the neural and endocrine mechanisms of vocal-acoustic communication.Reproduc-tively active female plainfin midshipman fish use their auditory sense to detect and locate“singing”males,which produce a multiharmonic advertisement call to attract females for spawning.The seasonal onset of male adver-tisement calling in the midshipman fish coincides with an increase in the range of frequency sensitivity of the female’s inner ear saccule,the main organ of hearing,thus leading to enhanced encoding of the dominant frequency components of male advertisement calls.Non-reproductive females treated with either testosterone or 17β-estradiol exhibit a dramatic increase in the inner ear’s frequency sensitivity that mimics the reproductive fe-male’s auditory phenotype and leads to an increased detection of the male’s advertisement call.This novel form of auditory plasticity provides an adaptable mechanism that enhances coupling between sender and receiver in vocal communication.This review focuses on recent evidence for seasonal reproductive-state and steroid-dependent plasticity of auditory frequency sensitivity in the peripheral auditory system of the midshipman fish.The potential steroid-dependent mechanism(s)that lead to this novel form of auditory and behavioral plasticity are also dis-cussed. 展开更多
关键词 auditory plasticity hair cells SACCULE sex steroids tuning.
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