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91.
Jana Brabcová Robert Hanus Richard Tykva Věra Vlasáková Bohuslav ?erný Zdeněk Wimmer Marie Zarevúcka 《Pesticide biochemistry and physiology》2011,101(2):103-108
Considering a potential application of selected biochemically activated insect hormonogen substances (juvenogens) against pest termite species, we aimed this study to describe the metabolism of these compounds by termites and soil bacteria and to evaluate the potential impact of their metabolites on the environment. Radiolabelled derivatives of the juvenogens cis- and trans-isomers of ethyl N-{2-[4-(2-butanoyloxycyclohexyl)methyl]phenoxy}ethyl carbamate were metabolized by the termite Reticulitermes flavipes and the bacteria Bacillus simplex and Bacillus sp., strain 05 (GenBank EU399813) giving rise to different numbers of metabolites. The trans-isomer of the juvenogen was metabolized by both Bacillus species into its parent synthetic structure, ethyl trans-N-{2-[4-(2-hydroxycyclohexyl)methyl]phenoxy}ethyl carbamate, while the cis-isomer was metabolized into further products. Both racemic juvenogens were metabolized bytermites, affording mainly the parent juvenoids. In terms of ecotoxicity, the trans-juvenogen shows a significantly lower toxicity than the cis-juvenogen. In contrast, the toxicity of the cis-juvenoid (main degradation product of cis-juvenogen) is higher than the toxicity of trans-juvenoid (main degradation product of trans- juvenogen). The precursors of the two juvenogens cis- and trans-2-(4-hydroxybenzyl)cyclohexanol were also tested but exhibited a low toxicity. The results demonstrate that bacteria can metabolize the juvenogen in liquid media culture and have implications for the development of a strategy for bioremediation of soil. Moreover, the products of the biodegradation exhibited low toxicity. Both juvenogens have a high juvenilizing effect, cause low mortality and are stable within a period of two weeks. 相似文献
92.
Lee JC Bruck DJ Dreves AJ Ioriatti C Vogt H Baufeld P 《Pest management science》2011,67(11):1349-1351
In August 2008, the first detection of the spotted wing drosophila, Drosophila suzukii, to the North America mainland in California caused great concern, as the fly was found infesting a variety of commercial fruits. Subsequent detections followed in Oregon, Washington, Florida and British Columbia in 2009; in Utah, North Carolina, South Carolina, Michigan, and Louisiana in 2010; and in Virginia, Montana, Wisconsin, Pennsylvania, New Jersey, Maryland and Mexico in 2011. In Europe, it has been detected in Italy and Spain in 2009 and in France in 2010. Economic costs to the grower from D. suzukii include the increased cost of production (increased labor and materials for chemical inputs, monitoring and other management tools) and crop loss. An effective response to the invasion of D. suzukii requires proper taxonomic identification at the initial phase, understanding basic biology and phenology, developing management tools, transferring information and technology quickly to user groups, and evaluating the impact of the research and extension program on an economic, social, and environmental level. As D. suzukii continues to expand its range, steps must be initiated in each new region to educate and inform the public as well as formulate management tactics suitable for the crops and growing conditions in each. 相似文献
93.
Haladová E Mojžišová J Smrčo P Ondrejková A Vojtek B Prokeš M Petrovová E 《Acta veterinaria Hungarica》2011,59(1):77-86
The objective of the study was to determine the immunostimulatory effect of β-(1,3/1,6)-D-glucan in puppies. The effect exerted on the efficacy of vaccination, especially against canine parvovirus and rabies infection, was studied. The application of vaccine and glucan leads to significant increases in the nonspecific immunological parameters (phagocytic ability of leukocytes, blastogenic response of lymphocytes, metabolic and chemotactic activity of polymorphonuclear cells). The level of antibodies against canine parvovirus (Ab CPV) and rabies infection reached the most statistically significant values on the 28th day after the application of vaccine and a syrup containing β-(1,3/1,6)-D-glucan (Group GV) as compared to the control group (Group V, puppies receiving only vaccine). Dogs without glucan supplementation did not produce such significant levels of antibodies. We can conclude that glucan has relevant immunostimulatory effects in dogs with altered immunity. The glucan product tested in this study (PleraSAN V, PLEURAN, Bratislava, Slovakia) could be used in the small animal clinical practice. 相似文献
94.
Marianna V??tkov?? Katar??na Dercov?? Jana Moln??rov?? L??via T??thov?? Bystr??k Polek Jana Godo???kov?? 《Water, air, and soil pollution》2011,218(1-4):145-155
Biodegradation of pentachlorophenol (PCP) in soil by autochthonous microflora and in soil bioaugmented by the bacterial strain Comamonas testosteroni CCM 7530 was studied. Subsequent addition of lignite, an abundant source of humic acids, has also been investigated as possible sorbent for PCP immobilization. Biodegradation of PCP and number of colony-forming units were determined in the three types of soil, haplic chernozem, haplic fluvisol, and haplic arenosol, freshly spiked with PCP and amended with tested sorbent. The enhancing effect of sorbent addition and bioaugmentation on PCP biodegradation depended mainly on the soil type and the initial PCP concentration. Microbial activity resulted in biotransformation of PCP into certain potentially toxic substances, probably lower chlorinated phenols that are more soluble than PCP, and therefore more toxic toward present biota. Therefore, it was necessary to monitor soil ecotoxicity during biodegradation. Addition of lignite resulted in a significant improvement of PCP biodegradation and led to a considerable decrease of soil toxicity especially in bioaugmented soils. The method could potentially serve as a promising technique in remediation technology for reducing high initial PCP content in contaminated soils. 相似文献
95.
Koszykowska M Calka J Szwajca P Jana B 《The Journal of reproduction and development》2011,57(1):62-71
The effect of estradiol-17β (E(2)) on the number and distribution of neurons in the caudal mesenteric ganglion (CaMG) supplying the ovary of adult pigs was investigated. Also, the numbers of ovarian dopamine-β-hydroxylase (DβH-), neuropeptide Y (NPY-), somatostatin (SOM-), galanin (GAL-) and estrogen receptor (ER)-immunoreactive perikarya as well as the density of the intraganglionic nerve fibers containing DβH and/or NPY, SOM, GAL were determined. E(2) was administered i.m. from day 4 of the first studied estrous cycle to the expected day 20 of the second studied cycle. Injections of E(2) (1) increased the E(2) level in the peripheral blood approximately 4-5 fold, (2) decreased the number of small-sized Fast Blue-positive postganglionic neurons in the CaMG, (3) decreased the number of small perikarya in the ventral, dorsal and central regions of the CaMG, (4) decreased the number of large perikarya in the dorsal and central regions, (5) decreased the number of small and large perikarya in the CaMG that were DβH(+)/NPY(+), (6) decreased the number of small DβH(+) but NPY(-) perikarya, (7) decreased the number of small perikarya coded DβH(+)/SOM(+) and DβH(+)/SOM(-), (8) decreased the number of small DβH(+)/GAL(-) perikarya, (9) decreased the number of small and large perikarya expressing ER subtypes α and β and (10) decreased the total number of nerve fibers in the CaMG containing DβH and/or NPY and DβH and/or GAL. These results show that long-term E(2) treatment of adult gilts downregulates the populations of both noradrenergic and ERs expressing ovarian neurons in the CaMG. Our findings suggest also that elevated E(2) levels that occur during pathological states may regulate gonadal function(s) by affecting ovary supplying neurons. 相似文献
96.
97.
Pikula J Adam V Bandouchova H Beklova M Horakova J Horakova H Kizek R Krizkova S Skocovska B Supalkova V Svoboda M Tremi F Vitula F 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2007,36(4):361-363
Background: Many causes of mortality in the European brown hare, such as bacterial and viral infections, anticoagulant poisoning, and trauma, may result in hemorrhage. There are, however, no reference values concerning blood clotting in this species. Objectives: The aim of this study was to determine reference values for blood coagulation times and related parameters in healthy European brown hares. Methods: Blood samples from 30 clinically healthy adult hares (15 males and 15 females) were obtained. Hares were physically restrained for blood collection from the cephalic vein into tubes containing citrate and EDTA. Results: Mean ± SD were obtained for thrombin time (TT) (13.97 ± 1.37 seconds), prothrombin time (PT) (13.32 ± 2.15 seconds), activated partial thromboplastin time (APTT) (16.73 ± 1.86 seconds), fibrinogen concentration (2.98 ± 1.06 g/L), and platelet count (355.28 ± 128.73 × 109 /L). Conclusions: Reference values for blood coagulation times and other parameters associated with blood clotting will be useful in the laboratory evaluation of hemorrhage in the European brown hare. 相似文献
98.
BACKGROUND
Combining different biocontrol agents, particularly micro- and macroorganisms, can contribute to new and sustainable pest control approaches. Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is one of the most destructive pests of solanaceous crops. An emerging management strategy consists of biological control using microbial insecticides such as baculoviruses, but with limited efficacy. Thanks to their high target specificity, baculoviruses can be used simultaneously with natural enemies such as parasitoids for improved control of T. absoluta. However, potential indirect nontarget effects of baculoviruses on parasitoids can result from overlapping resource requirements. We assessed whether ovipositing parasitoid females discriminated against virus-treated hosts and examined the outcome of within-host competition between the hymenopteran parasitoids Necremnus tutae (Reuter) (Eulophidae) and Dolichogenidea gelechiidivoris Marsch (Braconidae), and the Phthorimaea operculella granulovirus (PhopGV, Baculoviridae) that infects T. absoluta larvae.RESULTS
Female D. gelechiidivoris discriminated against virus-treated hosts, whereas N. tutae did not. We found few indirect virus-related effects depending on the species, the sex, and the time of virus treatment. Effects were ambivalent for D. gelechiidivoris offspring and ranged from increased male longevity when infection occurred before parasitization to reduced emergence and male longevity when infection occurred after parasitization. N. tutae offspring showed a longer development time and shorter male longevity when they developed in virus-treated hosts.CONCLUSION
The virus had a low impact on parasitoid offspring. In rare cases, adverse effects were detected; however, the low magnitude of these effects is unlikely to reduce the fitness of parasitoid offspring, therefore both parasitoids seem compatible with the baculovirus for control of T. absoluta. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献99.