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71.
红火蚁的危害及其防治   总被引:2,自引:0,他引:2  
谭速进 《四川动物》2005,24(2):230-232,236,F003
一种非常危险的入侵性害虫——红火蚁近年在我国台湾和香港登陆,对中国大陆和亚洲其他地区构成严重威胁。本文介绍了红火蚁的危害以及对红火蚁的防治方法。  相似文献   
72.
The incidence of imported malaria has been increasing in Korea. We reviewed data retrospectively to evaluate the epidemiology, clinical features, and outcomes of imported malaria from 1995 to 2007 in a university hospital. All patients diagnosed with imported malaria were included. Imported malaria was defined as a positive smear for malaria that was acquired in a foreign country. A total of 49 patients (mean age, 35.7 year; M : F = 38 : 11) were enrolled. The predominant malarial species was Plasmodium falciparum (73.5%), and the most frequent area of acquisition was Africa (55.1%), followed by Southeast Asia (22.4%) and South Asia (18.4%). Fourteen-patients (30.6%) suffered from severe malaria caused by P. falciparum and 1 patient (2.0%) died of multiorgan failure. Most of the patients were treated with mefloquine (79.2%) or quinine (10.2%); other antimalarial agents had to be given in 13.2% treated with mefloquine and 44.4% with quinine due to adverse drug events (ADEs). P. falciparum was the most common cause of imported malaria, with the majority of cases acquired from Africa, and a significant number of patients had severe malaria. Alternative antimalarial agents with lower rates of ADEs might be considered for effective treatment instead of mefloquine and quinine.  相似文献   
73.
ABSTRACT Although nest predation is often the single largest source of mortality in avian populations, manipulative studies to determine predator impacts on nest survival are rare, particularly studies that examine impacts of mid-size mammalian predators (hereafter, mesopredators) on nest survival of shrub-nesting birds. We quantified nest survival and identified nest predators of shrub-nesting songbirds within 4 large (approx. 40-ha) exclosures and 4 control sites within a longleaf pine (Pinus palustris) ecosystem. During 2003–2006, we located and monitored 535 shrub nests (222 with videography) for 4,804 nest-days to quantify daily nest survival and document predation events. We found no support for a treatment effect, suggesting mesopredators had little impact on daily nest survival (0.9303 in controls and 0.9260 in exclosures) of shrub-nesting songbirds. For the 5 most commonly monitored species, daily nest survival within species was constant. Our analysis suggested that shrub nests were most vulnerable during the nestling stage and presence of cameras on nests increased survival with the increase in survival being more pronounced during the incubation stage. We filmed 107 nest predation events, identifying predators at 88 nests. Of these 88 nests, snakes caused 33%, red imported fire ants (hereafter fire ants, Solenopsis invicta) 28%, raptors 17%, corvids 8%, mesopredators 6%, and small mammals 8% of nest predations. Cause-specific nest predation in controls and exclosures did not differ from expectation, providing evidence that compensatory predation did not occur. Nest predators differed from expectation with regard to nest stage; fire ants and raptors only depredated nests during the nestling stage. Presence of cameras had no effect on nest abandonment. Fire ants were the most prevalent nest predator, and nest predation by fire ants was only observed on nestlings, potentially reducing likelihood of renesting. Magnitude and timing of fire ant predation suggests that fire ants may be the most influential nest predator of shrub-nesting birds within the longleaf pine ecosystem. Our data suggest that controlling mesopredators will have no effect on nest success of shrub-nesting birds within longleaf pine forests.  相似文献   
74.
The red imported fire ants, Solenopsis invicta (Buren), are generally considered pests. They have also been viewed as beneficial predators feeding on other insect pests of various agroecosystems. This study documents the foraging habits of fire ants in a sweetpotato field in Mississippi. Fire ant foraging trails connecting outside colonies to a sweetpotato field were exposed and foraging ants moving out of the field toward the direction of the colony were collected along with the solid food particles they were carrying. The food material was classified as arthropod or plant in origin. The arthropod particles were identified to orders. Fire ant foragers carried more arthropods than plant material. Coleoptera and Homoptera were the most abundant groups preyed upon. These insect orders contain various economically important pests of sweetpotato. Other major hexapod groups included the orders Hemiptera, Diptera and Collembola. The quantity of foraged material varied over the season. No damage to sweetpotato roots could be attributed to fire ant feeding. Imported fire ant foraging may reduce the number of insect pests in sweetpotato fields.  相似文献   
75.

Displays of the pukeko, Porphyrio porphyrio melanotus Temminck (Gruiformes: Rallidae) are described and analysed quantitatively. Aggressive displays centre around the beak, which is presented to the opponent in a position from which a peck can be given. Submissive or escape displays centre around the white undertail coverts, which appear to have evolved as a distinct submissive signal since they are in sharp contrast to the aggressive releaser, both in location and colour. Raising the wings serves to expose the undertail and to provide a contrasting frame. The development of the white undertail as a submissive signal may have paralleled the development of the large frontal shield, which serves to maximise the aggressive releaser. Most displays are ambivalent, signalling both aggression and escape. With increasing escape tendency the bill and frontal shield are so placed that pecking is decreasingly likely, and the wings are increasingly raised. In postures with high escape tendency the beak is placed on the ground or removed from the opponent's view, but only in pure escape postures are the white undertail coverts prominent. Displays which involve rapid removal of the beak and shield from the opponent's view are more common in close contact situations, such as hierarchical interactions between pukeko of the same group. A brief comparison is made with other published reports on gallinules.  相似文献   
76.
对辽宁省2019年的3例境外输入性三日疟疟疾病例进行了实验室检测与诊断分析。 收集并进行流行病学调查与资料汇总。根据疟疾实验室现有最新执行诊断标准《疟疾的诊断》(WS259-2015)的要求,对临床诊断的疑似三日疟患者采集抗凝血制作血涂片镜检、进行疟疾快速诊断检测(RDT),上送全血到辽宁省疾病预防控制中心进行病例复核,巢氏PCR检测并进行测序比对。3份病例患者外周血血涂片镜检薄厚血膜,虫体分期主要为环状体期、大滋养体期、配子体期和成熟裂殖体期,其中大滋养体期中疟色素呈深棕色、较大、沿边缘分布,发现寄生的红细胞通常不胀大甚至会缩小,配子体小而圆,根据镜下特点初步判定为三日疟原虫;RDT结果提示为感染除恶性疟以外的其他3种疟疾(三日疟、卵形疟、间日疟)的单一感染,省级参比实验室对于上送全血利用巢氏PCR检测技术进行复核检测;将扩增出的三日疟的目的片段产物序列送至上海维基基因测序公司进行序列分析比对,基因序列同源性达到了100%。 同时使用血涂片镜检、进行疟疾快速诊断检测(RDT)和PCR进行检测,实验结果均鉴定为三日疟,根据病例的流行病学调查和临床表现确定为境外输入性三日疟病例。  相似文献   
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