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791.
There are a variety of ways to diminish the negative impacts of forest management for timber on biodiversity. A pilot project using a uniform spacing method of selective cutting was recently implemented in the 5340 ha Guarani Reserve, Misiones, Argentina, to design adequate management schemes for the subtropical forests of the region. Uniform spacing involves moderate timber harvesting and careful selection of remnant trees. In this article we compare tree regeneration in forests experimentally cut by diameter limit and uniform spacing methods. Seedlings of five size classes from 10 cm to 3 m in height were sampled using rectangular nested plots. Three years after cutting, an average of 54,330 and 22,270 seedling/ha (all height classes combined) of commercial and non-commercial species were found in the forest cut by uniform spacing and by minimum diameter, respectively. In an adjacent uncut forest there were 34,900 seedlings/ha, and in another forest cut by minimum diameters 30 years ago there were 50,000 seedlings/ha, The forest cut by uniform spacing had the highest number of commercial seedlings/ha, with three times as many as the forest cut by minimum diameter three years ago and twice as many as the forest treated by minimum diameters 30 years ago. The forest cut by uniform spacing and the forest treated by minimum diameters 30 years ago had the highest diversity of understory plants other than trees, as well as heterogeneous canopy cover, while the other two forests had a predominance of bamboo in the understory and more open canopy conditions. Although lack of site replication limits interpretation of the results, these early findings suggest that the uniform spacing method can be an ecologically sound forest management option for the region. 相似文献
792.
Santos Ana Nunes Jesus Ronald Ferreira Macedo Lilian Cristina Santos Jeannie Nascimento Vasconcelos Melo Francisco Tiago 《Systematic parasitology》2022,99(4):437-445
Systematic Parasitology - Parapharyngodon spp. are nematodes parasites of amphibian and reptiles worldwide distributed. Of 55 valid species, only 11 are known for the Neotropical realm, and six... 相似文献
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A Comparison of the Distribution of Intestinal Bacteria in British and East African Water Sources 总被引:4,自引:4,他引:0
S ummary . Various workers have suggested that there are marked regional variations in the distribution of intestinal bacteria used as indicators of pollution in water supplies. This paper presents the results of investigations into the distribution of some intestinal indicators (coliforms, * Escherichia coli , faecal streptococci and anaerobic lactobacilli) in water sources in the United Kingdom and in Kenya. The surveys showed that the differences in distribution were not significant except for some coliforms ( Citrobacter and Klebsiella spp.), but that survival subsequent to excretion was affected by ambient temperature. 相似文献
795.
Fred Monje Daniel Kadobera Deo Birungi Ndumu Lilian Bulage Alex Riolexus Ario 《PLoS neglected tropical diseases》2021,15(4)
Rabies is a vaccine-preventable fatal zoonotic disease. Uganda, through the veterinary surveillance system at National Animal Disease Diagnostics and Epidemiology Centre (NADDEC), captures animal bites (a proxy for rabies) on a monthly basis from districts. We established trends of incidence of animal bites and corresponding post-exposure prophylactic anti-rabies vaccination in humans (PEP), associated mortality rates in humans, spatial distribution of animal bites, and pets vaccinated during 2013–2017. We reviewed rabies surveillance data at NADDEC from 2013–2017. The surveillance system captures persons reporting bites by a suspected rabid dog/cat/wild animal, human deaths due to suspected rabies, humans vaccinated against rabies, and pets vaccinated. Number of total pets was obtained from the Uganda Bureau of Statistics. We computed incidence of animal bites and corresponding PEP in humans, and analyzed overall trends, 2013–2017. We also examined human mortality rates and spatial distribution of animal bites/rabies and pets vaccinated against rabies. We identified 8,240 persons reporting animal bites in Uganda during 2013–2017; overall incidence of 25 bites/ 100,000population. The incidence significantly decreased from 9.2/100,000 in 2013 to 1.3/100,000 in 2017 (OR = 0.62, p = 0.0046). Of the 8,240 persons with animal bites, 6,799 (82.5%) received PEP, decreasing from 94% in 2013 to 71% in 2017 (OR = 0.65, p<0.001). Among 1441 victims, who reportedly never received PEP, 156 (11%) died. Western region had a higher incidence of animal bites (37/100,000) compared to other regions. Only 5.6% (124,555/2,240,000) of all pets in Uganda were vaccinated. There was a decline in the reporting rate (percentage of annual district veterinary surveillance reports submitted monthly to Commissioner Animal Health by districts) of animal bites. While reported animal bites by districts decreased in Uganda, so did PEP among humans. Very few pets received anti-rabies vaccine. Evaluation of barriers to complete reporting may facilitate interventions to enhance surveillance quality. We recommended improved vaccination of pets against rabies, and immediate administration of exposed humans with PEP. 相似文献
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Astrid Reubsaet Liesbeth A.D.M. van Osch Hein de Vries Maaike R. Op de Coul Lilian Lechner 《Cancer epidemiology》2009,33(3-4):194-200
Background: The present study examined the effects of the campaign “early detection of cancer” on knowledge, attitudes, awareness, and intention to perform passive detection and timely seeking medical help. Further, the campaign was evaluated on recall and recognition and the various campaign components were evaluated. Methods: A longitudinal study using a Solomon four-group design among 784 Dutch adults aged 55 years and older was conducted. Data was gathered by means of telephone interviews. Results: The results showed moderate levels of campaign awareness. After the campaign, solely respondents who received a pre-test questionnaire and were aware of the campaign had significant higher cancer knowledge levels regarding passive detection. Respondents who were only aware of the campaign were significantly more willing to perform passive detection behavior and to timely seek medical help in the future. Further, they were more aware that paying attention to cancer warning signs can lead to early detection of cancer. Conclusions: It can be concluded that solely the combination of the pre-test questionnaire and exposure to the campaign had a significant positive impact on respondents’ cancer knowledge levels. The effects of the campaign on intention and awareness are indistinct and could be a consequence of (the results of) a self-selection bias. It seems that the dose, frequency, and duration of the campaign should be increased in order to substantiate the effects of the campaign. 相似文献