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61.
E. R. Campagnolo L. R. Lind J. M. Long M. E. Moll J. T. Rankin K. F. Martin M. P. Deasy V. M. Dato S. M. Ostroff 《Zoonoses and public health》2014,61(5):346-355
Rabid free‐ranging cats have been a public health concern in Pennsylvania since raccoon variant rabies first was recognized in the state in the early 1980s. Over the last decade, between 1.5 and 2.5% of cats submitted to Pennsylvania's state laboratories for rabies testing have been positive. In this report, we describe the extent of rabies in free‐ranging cats in Pennsylvania. We also present two examples of human exposure to rabid free‐ranging cats that occurred in Pennsylvania during 2010–2011 and the public health actions taken to address rabies exposure in the humans and animals. We then describe the concerns surrounding the unvaccinated and free‐ranging cat population in Pennsylvania and possible options in managing this public and animal health problem. 相似文献
62.
农药地下水暴露模型China-PEARL已开始在我国农药地下水风险评估中应用。本文利用China-PEARL潍坊市场景数据,为PRZM-GW构建了潍坊市场景。在潍坊市场景下,利用2个模型计算了56种农药在5种作物上共计145种施用方式下的预测环境浓度(PEC)值,利用商值法(RQ)进行风险评估。结果显示有8种农药共13种施用方式在潍坊市场景下存在不可接受的地下水风险。其中,2个模型均显示有不可接受风险的农药是多菌灵和氟磺胺草醚。2个模型PEC值比较结果显示,PRZM-GW的农药风险评估趋势与China-PEARL一致性高,从而验证了China-PEARL的可信性。模型PEC值影响因素分析显示,土壤有机碳分配系数(Koc)对2个模型输出影响最大,可将Koc>400L·kg-1作为判断某种农药预测浓度<0.1μg·L-1经验性指标。2个模型的PEC值和土壤好氧半衰期的对数呈线性关系,当土壤好氧半衰期>10d时,模型的PEC值随土壤好氧半衰期的增大而迅速增高。水解半衰期为PRZM-GW模型输入项,决定了PRZM-GW模型模拟的农药浓度随年变化趋势。水中溶解度是China-PEARL的输入项,但对模型PEC值影响很小。 相似文献
63.
F.?Ishiguri S.?Maruyama K.?Takahashi Z.?Abe S.?Yokota M.?Andoh N.?YoshizawaEmail author 《Journal of Wood Science》2003,49(2):135-139
Sugi green logs with red or black heartwood were smoke-heated, and the changes in the color of the heartwood after ultraviolet
(UV) (λ = 365 nm) radiation exposure were then observed. After UV radiation exposure, the redness and yellowness increased in both
the red and black heartwoods, whereas the brightness decreased. In the black heartwood, the resulting color turned from yellowish
white to reddish brown. Reddening in black heartwood after exposure to a combination of smoke heating and UV radiation is
thought to be due to a decrease in brightness and an increase in both redness and yellowness. However, the degree of change
in heartwood color by UV radiation exposure was not greatly affected by smoke-heating treatments of various lengths. When
methanol extracts were fractionated and exposed to UV radiation, the yellowness increased in the n-hexane-soluble portion and the redness increased in the acetone-soluble fractions from the n-hexane-insoluble portion. These results suggest that the n-hexane-soluble fraction contains the substances that allow heartwood color to change to yellow after UV radiation exposure,
and the acetone-soluble-fraction from the n-hexane-insoluble portion contains the substances that allow it to change to red.
Received: November 14, 2001 / Accepted: June 3, 2002
Acknowledgment This research was supported in part by a Grant-in-Aid for Scientific Research from the Japan Society for the Promotion of
Science.
This study was presented in part at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001
Correspondence to:N. Yoshizawa 相似文献
64.
There is growing interest in urban green space exposure estimated dynamically by accounting for individuals’ mobility during daily life. We aimed to explore if daily green space exposure estimates based on individuals’ mobility substantially differ from static home-based exposure estimates, and to examine potential effect modification by personal (sex and work status) and temporal (weekends versus weekdays) characteristics. To assess the association between daily exposure to urban green space, we used home address and time-activity data collected from 1911 participants in western New York, US, using their GPS-enabled mobile phones. We abstracted both individuals’ home address based (home-based) and daily time activity based (mobility-based) green space exposures from the Normalized Difference Vegetation Index (NDVI). Then, we assessed the association between mobility-based and home-based exposure estimates using linear mixed effect regression models with subject-specific random effects. We also explored whether this effect was modified by individual-level characteristics, including work status and sex, as well as whether assessments took place on weekdays versus weekends. We found that daily dynamic exposure to urban green space based on individuals’ mobility was not substantially different from static exposure estimates based on one’s residence, but that there were statistically significant effect modifiers. Specifically, the correspondence between mobility-based and home-based exposure to green space was relatively lower for employed compared to unemployed participants, whereas their correspondence during weekends increased compared to weekdays. Our findings suggest that there is a strong correspondence between mobility-based and home-based exposure to urban green space, but that their associations are modified by personal and temporal characteristics. Further research is needed to confirm our finding for general population in other settings, such as different seasons and other regions. 相似文献
65.
岩石裸露与水土流失关系研究现状及石漠化因子研究存在的问题 总被引:3,自引:2,他引:1
基岩裸露是喀斯特地区的常见现象,形成了类似荒漠景观的石漠化,而石漠化的发生发展影响了区域土壤侵蚀机理和结果,故需加大石漠化因子(D)与水土流失定量关系研究,以便修正土壤流失方程.因此,在中外文献查阅的基础上,总结了岩石裸露对坡面水土流失的影响相关研究现状.结果表明,岩石裸露对坡面水土流失的影响研究结论较为离散,主要... 相似文献
66.
The idea has been popular for a long time that Th1/Th2 imbalance is the major cause of many diseases. However, the Th1/Th2 paradigm has encountered increasing challenge since the discovery of a novel subset of Th cells, Th17. Th17 cells secrete a series of cytokines (IL-17A~F, IL-21 and IL-22), which is quite different from those produced by Th1 and Th2 cells. It is now generally accepted that Th17/IL-17A plays a pivotal role in autoimmune and host defense. Although first discovered in autoimmune diseases, emerging studies begin to explore the way in which Th17/IL-17A acts in chronic inflammatory airway diseases, such as asthma and chronic obstructive pulmanary disease. In this review, we will summarize the differentiation and function of Th17, and introduce the progress in the correlation between Th17/IL-17A and chronic inflammatory airway diseases. Further elucidating the mechanism of Th17/IL-17A-related pathophysiological changes will contribute to prevention and treatment of chronic inflammatory airway diseases. 相似文献
67.
奶牛慢性子宫内膜炎的治疗试验 总被引:7,自引:0,他引:7
选用乳酸环丙沙星、中药“孕宝”制剂两种药物对134头患有慢性子宫内膜炎的奶牛进行治疗对比试验。结果表明,乳酸环丙沙星治疗慢性卡他性子宫内膜炎、慢性卡他性脓性子宫内膜炎、隐性子宫内膜炎的治愈率分别为79.17%、72.73%、71.43%;“孕宝”治疗此3种慢性子宫内膜炎的治愈率分别为93.10%、72.73%、83.33%。乳酸环丙沙星治疗慢性卡他性脓性子宫内膜炎的效果优于“孕宝”,“孕宝”治疗慢性卡他性子宫内膜炎和隐性子宫内膜炎的效果则高于乳酸环丙沙星。 相似文献
68.
实验性慢性氟中毒家兔肝、肾动态超微病理学研究 总被引:1,自引:0,他引:1
24只20~30日龄体重0.7~1.2kg新西兰白兔随机分为实验组15只(每日每只随饮水摄取NaF45mg/kg体重)及健康对照组9只(饮用自来水).两组在相同饲养管理条件下实验观察.分别在实验第30,60.90d时迫杀,对肝和肾进行超微病理学研究.结果表明,肝和肾实质细胞膜系统损伤明显,胶原原纤维再生增多,且有再生障碍及再生后的损伤性变化. 相似文献
69.
LORRIE GASCHEN ALEXANDRE LEROUX JESSICA TRICHEL LAURA RIGGS HERMAN H. BRAGULLA NATHALIE RADEMACHER DANIEL RODRIGUEZ 《Veterinary radiology & ultrasound》2011,52(6):627-633
The magnetic resonance (MR) imaging findings of foals with infectious and noninfectious arthritis are described. Six foals with infectious arthritis and three foals with noninfectious arthritis were grouped based on synovial fluid analysis results and examined with radiography and MR imaging. Four out of six foals with infectious arthritis had osseous lesions in MR images indicative of osteomyelitis and only 4/19 lesions were detected on digital radiographs. The three foals with noninfectious arthritis had no osseous lesions in MR images or radiographically. Of the six joints that had osseous lesions detected with MR imaging, three had at least one lytic lesion detected radiographically. Osseous lesions in the epiphysis, metaphysis, and physis appeared in MR images as T2W, short tau inversion recovery, and proton density hyperintense foci with a hypointense halo. The same lesions appeared hyperintense in the 3D RSSG water excitation pulse sequence but lacked a surrounding hypointense halo. Most joints of foals with infectious arthritis had heterogenous signals within the synovial fluid whereas all of the nonseptic joints had homogenous synovial fluid signals. MR imaging appears to be better than radiography in the detection of osseous lesions in foals diagnosed with infectious arthritis and may be a valuable screening test for the presence of osteomyelitis. 相似文献
70.
Background, Aims and Scope Contaminated land is a high priority environmental problem in most of Europe and North-America. Sweden is no exception and
generic guideline values have been developed for the initial assessment, but site-specific assessments are also needed. The
generic guideline values are not applicable when the exposure conditions are different from the typical Swedish conditions
or when the site contains a particularly sensitive ecosystem. The Swedish guideline values have, like in many other countries,
been set by using deterministic point estimates for all variables and constants in the used multimedia model. The same approach
is common also for site-specific assessments, and a limitation is that it fails to quantify variability and uncertainty. Probabilistic
risk assessment provided a method to deal with this problem. Variability and uncertainty in the input parameters (variables
or constants) are described by probability distributions, and likewise the output (risk or exposure) is presented as a probability
distribution. A substantial number of probabilistic risk assessments for contaminated land at sites in North America, Europe
and Asia have been published. However, an extensive review of the literature did not identify any study where probabilistic
risk assessment was applied to a site contaminated by an iron or steel industry. Here we will describe such a case, where
we have compared a deterministic point estimate with a probabilistic risk assessment for six elements and benzo[a]pyrene.
Methods The site had different metallurgical plants in operation for more than 100 years. Most parts of the steel mill were closed
by the mid 1980s, and today the site is used by small-sized enterprises. The soil is contaminated with metals from the previous
industrial operations. The present owner plans to develop the site and has therefore initiated extensive investigations of
soil contamination. Sixty-two soil samples collected between 1997 and 2000 provided a good coverage of the whole site, and
were analyzed for the content of different elements and polycyclic aromatic hydrocarbons (PAH). The exposure assessments were
focused on six elements with high concentrations compared to the generic guideline values; arsenic (As), lead (Pb), cadmium
(Cd), chromium (Cr), copper (Cu) and zinc (Zn). In addition, benzo[a]pyrene was included due to the high toxicity and comparatively
high concentrations. Variability and uncertainty were characterized in a Monte Carlo simulation of exposures (10 000 iterations),
and the exposures were evaluated with two land use scenarios; less sensitive use and sensitive use.
Results and Discussion The deterministic point estimates and the probabilistic estimates of the 95th percentile are in approximately the same ranges
in the scenario of less sensitive land use. It is only the exposure for arsenic that is slightly above the toxicological reference
value (TRV) in the deterministic assessment. In the probabilistic assessment, the exposure for all elements is below the TRV.
The results for sensitive land use are applicable to a scenario where the site is developed for general housing. The deterministic
point estimates and the probabilistic estimates of the 95th percentile are also here in approximately the same ranges, but
the exposure exceeds the TRV for arsenic, cadmium and lead. Drinking water, vegetables grown on site and soil ingestion are
the major exposure pathways for this scenario. In this assessment, the estimated intake distributions are applicable to a
randomly selected individual. The probability distributions used here to characterize the different soil parameters are typically
representing both variability and uncertainty, and the same is true the majority of the exposure variables. We therefore decided
not to attempt to separate variability and uncertainty at this stage, but with additional data from a more in-depth site investigation
it might be possible to achieve this.
Conclusions and Outlook To the best of our knowledge, this study is the first report on a probabilistic risk assessment on a former iron and steel
works site. The materials handled by this industry were less toxic than for many other metallurgical operations, but contaminants
may still severely limit the options for future land use. This case study shows that probabilistic exposure estimates for
a set of soil contaminants can be quite similar to deterministic point estimates. The main difference is instead to be found
in the additional information obtained with the probabilistic assessment. The sensitivity analyses show pathways and input
variables that contribute most to variations in the total intake of each contaminant, e.g. dermal contact and ingestion of
soil, vegetables and drinking water. This information can be used both in the planning of future land use and for active measures
to reduce current exposure. The probabilistic assessment also provides information on the magnitude of exposure and the margin
of safety. This information may facilitate risk communication between decision-makers and stakeholders. The presentation of
results from probabilistic risk assessments is only briefly discussed in the literature and here we see a need for research
and opportunities for enhancement. The choice of data analytical tools may then be of importance, since more complex multimedia
models are rather difficult to decipher when implemented within traditional spreadsheet software. Some of the research needs
are identified here and in a previous review article in this journal. 相似文献