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1.
克瓦厚厉螨(Pachylaelaps kievati Davydova,1971),在所查到的献中仅描述了雌螨(KoponeBa,1977),本描述其雄螨及后若螨。  相似文献   

2.
3.
乳突寄螨雌螨描述(蜱螨亚纲: 革螨股: 寄螨科)   总被引:2,自引:1,他引:1  
乳突寄螨 Parasitus mammillatus ( Berlese,1 90 4 )雌螨 ,在所查到的文献中 ,仅记载有生殖区、头盖和螯钳的形状 [1 ,2 ] ,无其它描述。国内根据丹东标本曾描述该螨雄螨和后若螨 [3] 。本文根据朝鲜标本详细描述其雌螨。文中测量单位为 μm,括号内为测量均值。图 1- 7 乳突寄螨 Parasitus mammillatus (Berlese)1.背面 ;2 .腹面 ;3.头盖 ;4 .螯钳 ;5 .颚角 ;6 .须肢 ;7.跗节 乳突寄螨 Parasitus mammillatus ( Berlese,1 90 4 )雌螨 (图 1 - 7)体黄色 ,卵圆形 ,长 71 2 - 793( 758) ,宽 4 0 2 - 483( 4 50 )。背板覆盖整个背面 ,前背…  相似文献   

4.
东北常革螨过去仅描述雌螨和雄螨,本描述后若螨。中测量单位为μm。  相似文献   

5.
峰革赛螨幼若螨描述(蜱螨亚纲:革螨股:胭螨科)   总被引:1,自引:0,他引:1  
在所查到的献中,峰革赛螨Gamasellus montanus(Willmann,1936)仅描述了雌和雄螨(BpereToBa和Щep5aK,1977),本描述其后若螨、前若螨和幼螨。中测量单位为μm,括号内为测量均值。  相似文献   

6.
单角新革螨雌雄螨描述(蜱螨亚纲:革螨股:寄螨科)   总被引:2,自引:0,他引:2  
单角新革螨 Neogamasus unicornutus ( Ewing,1 90 9)同物异名为岛屿新革螨 Neogamasusislandicus( Sellnick,1 94 0 ) ,其后若螨 [1 ]、前若螨及幼螨 [2 ]已有较详细描述 ,但雌螨和雄螨在所查到的文献中只记载有个别特征 ,没有完整描述 [1 ,3- 6] 。本文根据采自集安的标本 ,描述其雌螨和雄螨。文中测量单位为 μm,括号内为测量均值。单角新革螨 Neogamasusunicornutus(Ewing,190 9)雌螨 (图 1 - 7)体黄色 ,卵圆形 ,长 6 78- 70 1 ( 6 89) ,宽 36 8- 41 4 ( 394 )。背板几乎覆盖整个背面 ,后部留狭窄裸露区。前背板长 345- 356 ( 349) ,…  相似文献   

7.
萎缩巨螯螨 Macrocheles reductus Petrova,1 96 6在所查到的文献中仅见雌螨描述(Брегетова,1 977)。本文描述其雄螨与后若螨 ,并补充雌螨特征。萎缩巨螯螨 Macrochelesreductus Petrova,1966雌螨形态补充描述 (图 1 - 2 ) 形态与原描述所绘图 ( Брегетова,1 977)比较 ,中国标本胸板后缘凹陷较深 ;腹肛板较狭长 ,长宽为 2 53- 31 0× 1 1 5- 1 4 9(平均 2 81× 1 30 )μm,呈有变异。图 1 萎缩巨螯螨 Macrocheles reductus Petrova♀1.胸板 ;2 .腹肛板变异雄螨 (图 1 - 4) 体黄色 ,椭圆形。背板 885× 575μm,后部明…  相似文献   

8.
记述革螨股Gamasina1新种,神农架枝厉螨Dendrolaelaps shennongjiaensis Ma et Liu,sp.nov,和角螨股Antennophorina1新种;新疆黑面螨Celaenopsis xinjiangensis Ma et Yc,sp.nov,角螨股在中国为首次记录。  相似文献   

9.
力氏广厉螨雄螨与后若螨描述(蜱螨亚纲:革螨股:厉螨科)   总被引:1,自引:0,他引:1  
马立名 《四川动物》2005,24(4):535-536
描述力氏广厉螨Cosmolaelaps hrdyi Sam(s)iň(a)k,1961 雄螨和后若螨.  相似文献   

10.
记述常革螨属1新种:湖北常革螨Vulgarogamasus huberensis Ma et Liu,sp.nov.和下盾螨属1新种:类刺下盾螨Hypoaspis spinaperaffinis Ma et Cui,sp.nov.。  相似文献   

11.
The present study investigated whether the increase of apoptosis in the placenta is associated with intrauterine fetal death in prostaglandin F receptor-deficient mice. Apoptosis was demonstrated within placental and decidual tissue by the TUNEL method. The majority of apoptosis was found in syncytiotrophoblast tissues. Enhanced TUNEL-positive staining in the syncytiotrophoblast layer was scattered in the placental tissues in clusters of apoptotic cells in the death group. Marked TUNEL-positive cells were identified in decidua of both groups. The rate of apoptosis in the placenta and decidua in the death group was higher than that in the survival group (P < 0.05). Immunohistochemical analysis showed that the level of active caspase-3 protein expression in the placenta in the death group was much higher than that in the survival group. The level of Bcl-2 protein expression in the placenta in the death group was much lower than that in the survival group. Western blot analysis demonstrated that increased expression of the active form of caspase-3 was detected in the placenta and decidua in the death group compared with that in the survival group. In contrast, a decrease in the expression of Bcl-2 was detected in the placenta and decidua in the death group compared with that in the survival group. Enhanced expression of Bax:Bcl-2 ratio was detected in placenta and decidua in the death group compared with that in the survival group. Thus, significantly increased apoptosis in the mouse placenta and decidua might be involved in the pathophysiologic mechanism of intrauterine fetal death.  相似文献   

12.
The latent periods of saccadic eye movements in response to peripheral visual stimuli were measured in 8 right-handed healthy subjects using Posner's paradigm "COST-BENEFIT". In 6 subjects, the saccade latency in response to visual target presented in expected location in valid condition was shorter than that in neutral condition ("benefit"). Increase in saccade latency in response to the visual target presented in unexpected location in valid condition versus neutral condition took place only in 4 subjects ("cost"). A decrease in left-directed saccade latency in response to expected target presented in the left hemifield and increase in saccade latency in response to unexpected left target in comparison with analogous right-directed saccades were observed in valid condition. This phenomenon can be explained by the dominance of the right hemisphere in the processes of spatial orientation and "disengage" of attention.  相似文献   

13.
Phytoplankton, submerged macrophytes, zoobenthos and zooplankton communities were studied concurrently in three lochs which progressively increased in trophic state. The phytoplankton showed a change in dominance from Bacillariophyceae (Pennales) and Desmidaceae in the mesotrophic Loch of the Lowes to Bacillariophyceae (Pennales) and Cyanobacteria in eutrophic Balgavies Loch and to Bacillariophyceae (Centrales) and Chlorophyceae in hypertrophic Forfar Loch. The Nygaard Compound phytoplankton quotient rose from 1.2 in the Lowes to 12 in Forfar. There was a decrease in number of species of submerged macrophytes, and in depth of colonisation from 5 m in the Lowes to 2 m in Forfar which was proportional to the decrease in mean transparency. Macrophyte biomass, however, increased in proportion to the concentration of total phosphorus in the lochs. There was a decrease in species of littoral zoobenthos, but an increase in density of profundal benthos from the Lowes to Forfar. Zooplankton also showed an increase in density with enrichment, accompanied by changes in dominance. Calanoida were dominant in the Lowes; Cladocera in Balgavies and Cyclopoda in Forfar. The importance of these differences in understanding the effects of progressive enrichment and to the management of the lochs is discussed.  相似文献   

14.
The density of 23 macroinvertebrate species and the total macroinvertebrate biomass were compared between rice-fields treated with lindane and diazinon in June and alphamethine in August and untreated controls. The macroinvertebrates could be divided into four groups: (1) Taxa, in which the densities were lower in the insecticide treatment in July and August than in the non-insecticide treatment. (2) The Culicidae which occurred in the insecticide treatment in significantly lower density in July, but in significantly higher density in August. (3) Ischnura elegans (Vander L.) which was found in July after the lindane application in significantly higher numbers in the insecticide treatments, but in significantly lower numbers in the insecticide treatment in August after the application of the pyrethroid. In these three groups, we assumed that direct effects due to the insecticides toxicity were the reason for the differences in density. (4) The fourth group included three taxa in which the densities were significantly higher in the insecticide treatment in July and August than in the control. For this, indirect effects due to reduced biotic interactions may be responsible. The biomass was higher in the insecticide treatments in July, mainly because of a high increase in gastropod density, during the rest of the season it was similar between treatments and controls.  相似文献   

15.
In the rat, changes in dietary protein intake give rise to changes in the levels of ornithine transcarbamylase (OTC) in liver and small intestine--an increase in liver and decrease in small intestine. The changes in enzyme level are accompanied by similar changes in levels of specific mRNA. Thus in liver, there is an increase in the level of specific mRNA when protein intake is increased, whereas in small intestine there is a small decrease. Comparison of changes in specific mRNA with total poly-A-containing RNA showed that the change in OTC mRNA in liver paralleled the change in total RNA levels. In contrast, in small intestine the small decrease in OTC mRNA levels when protein intake was increased was in the face of an increase in the level of total mRNA. Whereas the level of OTC is 20-fold higher in liver than in small intestine, the mRNA level for the enzyme differs by only 2.5-fold.  相似文献   

16.
Variation in male lifetime breeding success (LBS) is central to understanding selection, yet it has rarely been measured in natural populations of large mammals. Here, we first describe variation in the opportunity for selection in cohorts of Soay rams (Ovis aries) on the archipelago of St. Kilda, Scotland, that were born during years of varying population density. Variation in LBS is closely coupled with demography, as rams born in years of low density following population crashes enjoy greater LBS than do those born in high-density years. Paradoxically, the opportunity for selection was greatest in the largest cohorts, those born in years of high population density, owing to low juvenile breeding success and overwinter survival. Variation in longevity and the contribution of nonbreeders were the most important components of the total variance in LBS in cohorts born in years of high density, while variation in fecundity was more important in cohorts born in low-density years. The opportunity for sexual selection is thus stronger in cohorts born in low-density years, as many rams in these cohorts survive to compete for mates as adults in subsequent ruts. Variation in population density in the year of birth also influenced the intensity of selection. Individuals born in years of high population density underwent strong natural selection in favor of longer hindlimbs over their first winter. In contrast, in cohorts born in low-density years, there was no natural selection on hindlimb in the first year of life. Longer hindlimbs were associated with increased fecundity over the entire lifetime of individuals born in low-density years. Natural and sexual selection thus act on the same trait in the same direction at different life-history stages in Soay rams, depending on the population density experienced in the year of birth.  相似文献   

17.
OBJECTIVES--To evaluate the success of the south Powys hydatid control programme by analysis of trends in cystic disease in humans and sheep and dog infestation. DESIGN--A review of hospital admissions for human hydatid disease in 1984-90, abattoir prevalence surveys of hydatid cysts in adult sheep, arecoline acetarsol and coproantigen surveys of prevalence of Echinococcus infestation in dogs. SETTING--All hospitals in England and Wales, three abattoirs, and dog populations in mid ands south east Wales. SUBJECTS--Residents of England and Wales admitted to hospital between 1984 and 1990 with a new diagnosis of human hydatid disease (International Classification of Diseases (ICD), ninth revision, code 122) acquired in the United Kingdom. RESULTS--The average annual incidence of human hydatid disease in Powys, mid-Wales, fell from 3.9x10(-5) in 1974-83 to 2.3x10(-5) in 1984-90. Age specific incidence rates in Wales declined over this period only in children, and no cases occurred in children (<15 years) in Powys. Two Welsh children who lived in Gwent and mid-Glamorgan were infected. Prevalence of hydatid cysts in old sheep from south Wales declined during the control period, but in 1993 prevalence of cysts was 13%. Prevalence of E granulosus infestation was zero in the control area in 1993, but it was 2.4% in Powys dogs outside the control area in 1989 and 9.2% in dogs in Gwent in 1991. CONCLUSIONS--Human hydatid disease has been successfully controlled in south Powys but cystic echinococcosis is still endemic in sheep in mid-Wales, and there is a focus of infection in humans, sheep, and dogs in the bordering areas of Gwent and mid-Glamorgan. There is considerable potential for an upsurge in human cases if control measures are relaxed.  相似文献   

18.
Serum thyroid hormone levels were determined in adult Atlantic salmon ( Salmo salar ) of both sexes caught in the ocean and at a sequence of locations on their return migration to spawn. Tri-iodothyronine (T3) levels were greatest in fish caught in coastal or estuarine waters or in a river near head-of-tide. T3 levels were lower in fish caught in rivers throughout the angling season and lowest in those captured entering a tributary near spawning. Thyroxine (T4) levels were lowest in immature fish captured in the ocean in winter but raised in fish captured in spring; many of the latter group showed endocrine evidence of their becoming sexually mature. T4 levels were greatest in fish captured in coastal waters and progressively lower in fish captured in an estuary, near head-of-tide and in rivers. T4 levels in fish captured at tributary entry near spawning exceeded those in fish caught in rivers earlier in the year. In general, these data support the hypothesis that motor activity level in migrant fish is a determinant of thyroid status.  相似文献   

19.
Temperature changes were recorded continuously in eleven nests of Formica polyctena located in Southern Finland and the Czech Republic. Nest temperatures were recorded in the Czech site from 2003 to 2005 and in Finland during 2004 – 2005. Seasonal changes in nest temperature were very similar in both locations. During summer, the ants maintained a relatively high and constant temperature in their nest in both locations. Summer nest temperatures in Finland were higher than those in Czech during 2004 –2005 but did not differ from those in Czech during 2003– 2004. This indicated that the geographical differences were less important than difference between seasons. Nest temperature peaked in June. During summer, daily temperature fluctuations were significantly lower in Finland than in Czechia probably due to shorter nights in Finland. Apparent differences in daily temperature patterns were found in nests with different moisture in both locations. In dry nests, temperature peaked in the evening and decreased overnight, whereas the apparent increase was delayed to the night in wet nests. The spring increase in temperature in wet nests was much steeper that that in the dry ones when whole spring period is considered. During one day, temperatures fluctuated much more in dry nests than in wet ones. These differences seem to be caused by differences in thermal capacity between dry and wet nests. Received 24 July 2006; revised 19 February 2007; accepted 19 May 2007.  相似文献   

20.
Villar R  Held AA  Merino J 《Plant physiology》1995,107(2):421-427
Dark respiration in light as well as in dark was estimated for attached leaves of an evergreen (Heteromeles arbutifolia Ait.) and a deciduous (Lepechinia fragans Greene) shrub species using an open gas-exchange system. Dark respiration in light was estimated by the Laisk method. Respiration rates in the dark were always higher than in the light, indicating that light inhibited respiration in both species. The rates of respiration in the dark were higher in the leaves of the deciduous species than in the evergreen species. However, there were no significant differences in respiration rates in light between the species. Thus, the degree of inhibition of respiration by light was greater in the deciduous species (62%) than in the evergreen species (51%). Respiration in both the light and darkness decreased with increasing leaf age. However, because respiration in the light decreased faster with leaf age than respiration in darkness, the degree of inhibition of respiration by light increased with leaf age (from 36% in the youngest leaves to 81% in the mature leaves). This suggests that the rate of dark respiration in the light is related to the rate of biosynthetic processes. Dark respiration in the light decreased with increasing light intensity. Respiration both in the light and in the dark was dependent on leaf temperature. We concluded that respiration in light and respiration in darkness are tightly coupled, with variation in respiration in darkness accounting for more than 60% of the variation in respiration in light. Care must be taken when the relation between respiration in light and respiration in darkness is studied, because the relation varies with species, leaf age, and light intensity.  相似文献   

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