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1.
The DNA damaging effects of the carbamate pesticide carbofuran and its four metabolites (carbofuranphenol, 3-ketocarbofuran, 3-hydrocarbofuran and nitrosocarbofuran) on mice were evaluated by single cell gel electrophoresis (SCGE) assay and micronucleus test. KM mice were exposed to test compounds with different doses of 0.1, 0.2 and 0.4mg/kg through in-traperitoneal injection two times with an internal of 24 h, and then killed by cervical dislocation 6 h after the second injection. In SCGE assay, isolated mice peripheral blood lymphocytes were employed to determine DNA damaging degree after a 1 h treatment by test compounds and a following electrophoresis. Carbofuran and carbofuranphenol showed negative results in both test and had no obvious toxicity. 3-hydrocarbofuran and nitrosocarbofuran were positive. 3-ketocarbofuran could not induce micronucleus formation but caused significant DNA migration in SCGE test. These tests revealed that 3-ketocarbofuran, 3-hydrocarbofuran and nitrosocarbofuran are pote  相似文献   

2.
Pollution of the aquatic environment is an ever-growing problem, as waters are the ultimate sink for the large number of xenobiotics from multiple sources. DNA damaging agents have a significant ecological relevance since they are implicated in many pathological processes and exert effects beyond that of individual being active through following generations. A large number of methods have been applied to evaluate genotoxic damage in different aquatic species. Comet assay, as method for de- tecting DNA alterations, and micronucleus test, as an index of chromosomal damage are the most widely applied and validated methods in field studies. These methods were applied in different vertebrate and invertebrate aquatic species, but only mollusk and fish species have been employed in routine biomonitoring programs. Mussels, due to their widely geographical distribution and the suitability for caging represent the bioindicator of choice in field studies. Mytilus species is the most used marine mussel. The use of fish is limited to specific geographic areas. The present review mainly focuses on the application of comet assay and micronucleus test in mussels. A number of biomonitoring studies in mussels, using comet assay or micronucleus test, revealed exposure to different classes of genotoxic compounds with a good discrimination power. The different evidence from the two as- says, reflects different biological mechanisms for the two genetic endpoints, DNA damage and chromosomal damage, suggesting their combined application in the field. Different endogenous and exogenous factors have been shown to modulate the genotoxic responses in mussels, acting as confounding factors in environmental monitoring. The use of standardized protocol for caging, sampling and genotoxity evaluation is critical in biomonitoring studies. The use of a multimarker approach coupling genotoxicity biomarkers with physiological and biochemical factors allows to have a complete picture of the environmental pollution [Current Zoology 60 (2): 273-284, 2014].  相似文献   

3.
Habitat quality can directly affect population abundance and distribution of the Yangtze finless porpoise. This study investigated habitat status of both south and north banks of the main stem of the Yangtze River by taking high-resolution digital photos systematically during the 2017 Yangtze Freshwater Dolphin Expedition from 10th November to 17th December, 2017. The survey area covered the entire middle and lower reaches of the Yangtze River from Yichang to Shanghai (1669 km in length) and a total of 794 photo samples were collected. We recorded 318 sightings with 631 individuals of the Yangtze finless porpoise. The Chi-squared goodness of fit test revealed that proportions of observed frequency are significantly higher than the expected frequency in natural river banks (χ2=69.81, P<0.001). Whereas the result is opposite in the semi-natural and solidified river banks (χ2=39.26, P<0.001; χ2=12.15, P<0.001), indicating that the natural river banks were the preferred habitat of the Yangtze finless porpoise. The length of the semi-natural river and solidified banks accounted for 45.47% of the total length of the river bank, which intermingled with the patches of the natural river banks, demonstrating that the natural habitat was severely degraded and highly fragmented to impact the distribution of the Yangtze finless porpoise. Our study suggested that habitat degradation and fragmentation pose a significant threat to the survival of the Yangtze finless porpoise. Future conservation research and practice should focus on habitat restoration of the solidified river banks to reestablish and enhance habitat connectivity. © 2019, Institute of Hydrobiology, Chinese Academy of Sciences. All rights reserved.  相似文献   

4.
In this paper, the author described the larvae of Chinese Chrysomyine flies. All larval specimens of the seven species studied in this paper were reared in the laboratory. The 7 species of Chrysomyinae are as follows: Chrysomya megacephala (Fab., 1794). Fig.1. Ch. pinguis (Wlk., 1858). Ch. bezziana Vill., 1914, Fig.2. Ch. defixa (Wlk., 1857), Fig.3. Achaetandrus rufifacies (Macq., 1842). Fig. 4a.b. Ach. villeneuvii (Patton. 1922). Fig. 4b. (right 5, 8.) Ceylonomyia nigripes (Aubt., 1932). Fig. 5. The larvae of following species are described for the first time.  相似文献   

5.
The distributions of many plant taxa in China at the present day indicate centres of floristic importance which may be ancient,and have evolutionary significance,or which may be only their latest locations in a Cenozoic history of migrations.This paper summarizes the present and Cenozoic distributions in China of the following taxa:Nitraria,Ephedra,Carya,Liquidamber,Pterocarya,Betulaceae.It is concluded that the centres of importance of the named genera are different now from what they were at some time in the Cenozoic past;each has accomplished major migrations and suffered significant extinctions during that period.The history of the Betulaceae is less clear but in principle soluble.  相似文献   

6.
Diet quality influences organismal fitness within and across generations.For herbivorous insects,the transgenerational effecets of diet remain relatively underexplored.Usinga3×3×2 factorial experiment,we evaluated how N enrichment in parental diets of Neolemd abbreviata(Larcordaire)(C oleoptera:Chrysomelidae),a biological control agent for Tradescantia fluminensis Vell.(Commelinaceae),may influence life history and performance of Fi and F2 offspring under reciprocal experiments.We found limited transgenerational effects of foliar nitrogen variability among life-history traits in both larvae and adults.Larval weight gain and mortality were responsive to parental diet contrary to feeding damage,pupal weight and duration taken to pupate.There were significant parental diet x test interactions in larval feeding damage,weight gain,pupal weight and time to pupation.Generally,offspring from parents under high N plants performed better even under low N test plants.Adult traits including oviposition selection,feeding weight and longevity did not respond to the efects of parental diet nor its interaction with test diet as was the case in the larval stage.However,the main efects of test diet were more important in determining adult performance in both generations suggesting limited sensitivity to parental diet in the adult stage.Our results show conflicting responses to parental diet between larvae and adults ofthe same generation among an insec species with both actively feeding larual and adult life stagee These tranegeneratinonal efferte,or lack thereof,may have implications on the field performance of N.abbrevita under heterogencous nutritional landscapes.  相似文献   

7.
To evaluate the role of bacterial symbionts ( Buchnera spp. ) in the black bean aphids ( Aphis craccivora Koch), the aphids were treated with the antibiotic, rifampicin, to eliminate their intracellular symbiotic bacteria. Analysis of protein and amino acid concentration in 7-day-old of aposymbiotic aphids showed that the total protein content per mg fresh weight was significantly reduced by 29 %, but free amino acid titers were increased by 17% . The ratio of the essential amino acids was in general only around 20% essential amino acids in phloem sap of broad bean, whereas it was 44% and 37% in symbiotic and aposymbiotic aphids, respectively,suggesting that the composition of the free amino acids was unbalanced. For example, the essential amino acid,threonine represented 21. 6% of essential amino acids in symbiotic aphids, but it was only 16.7% in aposymbiotic aphids. Likewise, two nonessential amino acids, tyrosine and serine, represented 8.9% and 5.6% of total amino acids in symbiontic aphids, respectively, but they enhanced to 21.1% and 13.6% in aposymbiotic aphids. It seems likely that the elevated free amino acid concentration in aposymbiotic aphids was caused by the limited protein anabolism as the result of the unbalanced amino acid composition.  相似文献   

8.
Three Gorges Reservoir (TGR) is the key project for the governance and development of the Yangtze River. TGR is an important region for the ecological and environmental protection in the Yangtze River economic belt. The hydrology and water environment have taken fundamental changes since the impoundment of TGR with some negative ecological and environmental problems. To address whether the aquatic ecosystem of TGR is healthy or not, the phytoplankton community index (PhyCoI) was used to assess the ecosystem health of TGR. Field survey was carried out on April 2015 in the whole region of TGR, including 23 tributary bays and 18 sections in the main channel of TGR with 173 sampling sites. A total of 61 phytoplankton taxa were identified, belonging to Cyanophyta, Chlorophyta, Bacillariophyta, Cryptophyta, Pyrrophyta, Euglenophyta, and Chrysophyta. Based on the scores of PhyCoI, the overall health status of TGR is good, with 68% sites in the status of very healthy (4≤PhyCoI<5) or healthy (3≤PhyCoI<4), 26% sites in sub-healthy (2≤PhyCoI<3), and 6% sites in general sick condition (1≤PhyCoI<2). Specifically, 96% sites in the main channel of TGR are healthy, and other 4% sites are in the status of sub-healthy. In the tributary bays, the ratios for the status of very healthy, healthy, sub-healthy, and general sick are 2%, 53%, 35%, and 9%, respectively. From the view of spatial distribution, overall health status of the main channel of TGR is good, and the health status of the main channel in Hubei Province is better than that in the Chongqing Province. In addition, the health status of sites in the Xiangxi Bay, Meixi Bay, and Xiaojiang Bay were highly variable. And in general, the health status of the bays near the dam of TGR is better than the bays far away from the dam. These results provide science and technology support for ecological and environmental protection of TGR. © 2019, Institute of Hydrobiology, Chinese Academy of Sciences. All rights reserved.  相似文献   

9.
To better understand zooplankton distribution and its relationship with the physical-chemical factors in middle Yangtze River, we collected 20 zooplankton samples from segments at Yichang, Jingzhou, Yueyang, Wuhan and Hukou in October, 2016. A total of 23 species that belong to 13 families and 14 genera were identified, among which 16 species belong to Rotifera, 4 to Copepoda and 3 to Cladocera. Among the five segments, the highest number of zooplankton species was detected at Hukou (9 species), while the lowest was at Yueyang (5 species). The average density at Wuhan (10.94±5.81) ind./L was higher than that at Hukou and the other segments. Rotifers (3.41±0.21) ind./L were dominant in the zooplanktonic community, and Keratella valga, Synchacta atylata and Keratella cochlearis were the dominant species. The average density of copepods (mainly nauplius) was (0.75±0.07) ind./L. Cladocera had the lowest average density. Similarly, the zooplankton biomass at Wuhan was also higher than that at Hukou and the other three segments. Comparing with studies at other segments of Yangtze River, we detected lower zooplankton diversity in our investigation. Spearman correlations indicated that the biomass and diversity of zooplankton were significantly and positively correlated (P<0.05) to chlorophyll a. © 2019, Institute of Hydrobiology, Chinese Academy of Sciences. All rights reserved.  相似文献   

10.
Before summing up the essential points brought forward in the present paper,it seems desirable at the outset to circumscribe briefly the geographical boundary of the Himalaya.We all know that the Himalaya is an extraordinarily gigantic upheaval of the landmass in the world,yet,up to the present,geologists and geographers are still divided in the concept of its geographical boundary.It has so far unequivocally been recognized that the mountain range west of the great bend of the famous Tsangpo Gorge in southeastern Tibet running  相似文献   

11.
Euhamitermes is a small genus of the termites subfamily Amitermitinae(family Termitidae).It was established by Dr.N.Holmgren in 1912.It istropical and subtropical,and is confined to be the Indo-Malayan Region.Onlyseven species are hitherto known more than seventy years.In China,Dr.Tsaiet Chen reported first E.hamatus from Yunnan in nieteen sixty,a newspecies E.zhejiangensis was described by Dr.He et Xia in 1982—83.Wedescribe here two new species,namely,Euhamitermes yuntaishanensis and  相似文献   

12.
The genus Shelfordia is discovered in China for the first time, and one new species of this genus ( S. chinensis sp. nov. ) is fully described and illustrated in the present paper. The type specimen is deposited in the Parasitic Hymenoptera Collection, Zhejiang University, Hangzhou, China.  相似文献   

13.
A zoological expedition was made from March to June, 1975, in Northeastern Yunnan at Southeast of Yangtze River (27°30′—28°40′ N., 103°15′—104°25′E.). 450 specimens of birds were collected. Orders and families treated in this paper are listed below:  相似文献   

14.
A total of 3 genera and 26 species of the Chinese Oretinae are represented in this paper; among them 13 species are described as new to science. All the type specimens are deposited in the Institute of Zoology. An account of the geographic distribution is given in accompanying with a distribution map. From the distribution of 23 species,of Oreta, the richest areas are ap-  相似文献   

15.
<正> The Cenozoic deposits of Jingle area was first explored by Teilhard de Chardin & Young in 1929, and six species of mammals: Hipparion houfenense, Gazella blacki Antilospira licenti, Elephas sp., Cervus sp., and Rhinocerotidae gen. indet, were found from the Red Clay in Loc. 1 (Hefeng). Based on the Jingle Fauna, Teilhard de Chardin & Young concluded that the fossil-bearing layer was situated between the typical Hipparion richthofeni Red Clay (Pontian) and the Sanmenian deposits (Polycene) (Teilhard de Chardin & Young, 1930, 1931) and called it "Upper Pontian". Since then, Jingle Formation (or Jingle Red Clay) has been widely used in the stratigraphic generalization of North China (Pei et al., 1963) although its definition and age assignment have never been cleared up. "Jinglean" was put into use for the first time as a stage name by Li et al. (1984, in Chinese) to represent Early Pliocene tentatively: "It may be equivalent to Early Pliocene, more plausibly, it is later ...... Jinglean was temporarily used here to represent Early Pliocene by tradition." In order to make clear the age of Jingle Red Clay and enrich the Hefeng Fauna, a field survey was made in the Summer of 1986 by Chen Xiaofeng and the author. An assemblage of fossil micromammals was unearthed by means of wet-sieving techniques. About 1 ton of sediments from Hefeng (Loc. 86007, or Loc. 1) and Xiagaoai (Loc. 86008, or Loc. 2) in Jingle county (see fig. 1), yielded over 1000 specimens of small mammals. The specimens are from four layers (see table 1), and the present paper only deals with the micromammals from the sand layer and the Red Clay at Hefeng (fig. 2).  相似文献   

16.
PAEs have been proved to be one of the major organic pollutants. The present study determined the level of PAEs using surface water samples from the upper reaches of the Yangtze River. The results showed that DEHP contributed the most to PAEs pollution, followed by DBP. Risk Quotients of PAEs were used for preliminary screening, and DEHP and BBP were identified as potential risk factors with RQ of 310 and 70.7. The MOS10 of DEHP and BBP were 1.40 and 1.32×105, respectively, indicating that BBP may pose little risk to aquatic organisms. The potential risk of DEHP was further analyzed with joint probabilistic curves. Among different biological groups, fish and zoobenthos were two major groups sensitive to DEHP-induced damage under current concentrations with 99.4% and 98.3% for 5% species of each group. While among the toxicity endpoints, reproduction may be more sensitive than others. The 5% and 10% aquatic species were suffered from reproductive damages by 100% and 97.8%, respectively. Overall, our results indicated that DEHP in the surface water of the upper Yangtze River may pose potential risk to aquatic organisms, especially on their reproduction. Therefore, more concerns should be paid in species protection and environmental management. © 2019, Institute of Hydrobiology, Chinese Academy of Sciences. All rights reserved.  相似文献   

17.
卢欣 《兽类学报》2001,21(3):231-233
Body condition is one of the indicators of wildlife population status. Kidney fat index[1] and weight-length index (body weight against cube body length)[2] are two common indicators for species of lagomorph. The latter is more convenient to measure in game management practice. This paper analyzed relative fatness (RF) of the cape hare( Lepus capensis) one of the most important game animals in China.  相似文献   

18.
Tianjinia, Shaozengia and Bohaicythere, the three new types of early Tertiarl non-marine ostracodes found in the Bohai Gulf, belong to Tianjininae Gong (subfam. nov.), Phacocyprinae Hou et Cai, 1978 and Limnocytherinae Klie,1938  相似文献   

19.
Nineteen kinds of spiro enol ether analogues were screened with larvae of Pieris rapae for antifeedant activity. The results showed that the antifeedant activity of compounds No.20 and No.12 was higher than others. In non-choice test, AFC50 values within 24 h of compounds No.20 and No.12 against 3rd instar larvae of P. rapae were 226.93ug/mL and 370.00ug/mL, and that in choice test against 4th larvae were 280.54 ug/mL and 398.88 ug/mL, respectively. Compd. No.20 could prolong the eggs hatch time and reduce the haemolymph content and the protein content in haemolymph of 4th instar larvae obviously. Compd. No.20 could protect tested leaves and control larvae of P. rapae effectively.  相似文献   

20.
ON THE EVOLUTION OF MEGACERINES   总被引:1,自引:1,他引:0  
<正> The megacerine deer (the tribe Megacerini of the subfamily Cervinae) is a rather ancient extinct group, known from the end of the Miocene, The tribe comprises 8 genera: Megaceros Owen, 1844, Sinomegaceros Dietrich, 1933, Praemegaceros Portis, 1920, Praedama Portis, 1920, Arvernoceros Heintz, 1970, Neomegaloceros Korotkevitch, 1971, Orchonoceros Vislobokova, 1979 and Praesinomegaceros Vislobokova, 1983. The Pleistocene history of megacerines is much studied regarding the evolutionary stage of these deer. Almost all students recognize the existence of two branches of megacerines in the Pleistocene of Europe: one of these connected with Megaceros giganteus (Blumenbach, 1803) and the other with Praemegaceros verticornis (Dawkins, 1872), although the estimations of the systematic range of these cervids are different (Azzaroli,  相似文献   

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