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291.
Vasconcellos ML Silva TM Camara CA Martins RM Lacerda KM Lopes HM Pereira VL de Souza RO Crespo LT 《Pest management science》2006,62(3):288-292
The molluscicidal activities of ten Baylis-Hillman adducts against Biomphalaria glabrata (Say) snails, the intermediate host of schistosomiasis, have been determined. Nine of these compounds showed significant molluscicidal activity against B. glabrata, falling below the threshold of 100 microg ml(-1) set for potential molluscicidal activity by the World Health Organisation. Among these compounds, 3-hydroxy-2-methylene-3-(4-nitrophenyl)propanenitrile had the highest activity, with LC(50) = 6.64 microg ml(-1). 相似文献
292.
Kimberly M. Webb Epifania Garcia Casiana M. Vera Cruz Jan E. Leach 《European journal of plant pathology / European Foundation for Plant Pathology》2010,128(3):399-407
Disease resistance genes most commonly used in breeding programs are single, dominant genes with relative effectiveness that
is sometimes influenced by plant developmental stage. Knowing the developmental stages at which a resistance gene is functional
is important for disease management. In rice, resistance at the seedling stage is crucial, because wounding during transplanting
increases the potential for bacterial blight disease, and not all bacterial blight resistance genes are effective at the seedling
stage. Effectiveness of the bacterial blight resistance genes Xa4, xa5, and Xa7, all in a common genetic background, was evaluated at different developmental stages by measuring lesion length and bacterial
numbers after inoculation with the bacterial pathogen, Xanthomonas oryzae pv. oryzae. The Xa4 and xa5 genes controlled disease at all growth stages. In contrast, Xa7 was not fully functional in very young seedlings, but was completely effective by 21 days after sowing (das). The effects
of plant developmental stage on interactions of the Xa7 gene with X. oryzae pv. oryzae strains carrying different mutant avrXa7 alleles were also tested. If a partial or fully functional avrXa7 allele was present, Xa7 resistance was effective at all growth stages tested after the transplant stage (>21 das). 相似文献
293.
294.
Cesar Rodriguez-Saona Vera Kyryczenko-Roth Daniel Schiffhauer Nicolas Firbas 《Journal of insect science (Online)》2020,20(6)
Due to changes in pest management practices, farmers’ reports of severe feeding injury to cranberries, Vaccinium macrocarpon Aiton Ericales: Ericaceae, caused by the cranberry toad-bug, Phylloscelis rubra Ball, have increased in recent years in New Jersey (United States). Currently, however, limited information is available on the effects of P. rubra feeding or density of individuals needed to cause injury to cranberry vines and fruit. In 2015‒2017, we conducted studies to characterize injury to cranberry at a range of P. rubra densities by using cages in a screen-house and field, to establish a correlation between P. rubra density and crop injury in an open field experiment, and to measure the effects of P. rubra injury on the nutritional content (i.e., amounts of macro- and microelements) of cranberry vines. Phylloscelis rubra feeding on cranberry vines produced typical injury symptoms at relatively low densities (i.e., 2 individuals per vine in field cages or <10 individuals per sweep net sample in open fields), which included discolored (yellowish or reddish) or dead (brown) vines. This vine injury could lead to reductions in fruit mass and total fruit number. However, P. rubra injury to cranberry vines did not alter their nutritional composition. In general, this study highlights the ability of P. rubra to cause substantial injury to cranberry vines even when population densities were relatively low, which could result in declines in fruit production (quality and quantity). Therefore, infestations by P. rubra in cranberries must be considered when making pest management decisions in regions where this insect is present. 相似文献
295.
296.
Yossi Tal Ari Ayalon Agnesa Sharaev Zoya Kazir Vera Brekhman Tamar Lotan 《Marine drugs》2014,12(2):734-745
Transdermal delivery is an attractive option for drug delivery. Nevertheless, the skin is a tough barrier and only a limited number of drugs can be delivered through it. The most difficult to deliver are hydrophilic drugs. The stinging mechanism of the cnidarians is a sophisticated injection system consisting of microcapsular nematocysts, which utilize built-in high osmotic pressures to inject a submicron tubule that penetrates and delivers their contents to the prey. Here we show, for the first time, that the nematocysts of the starlet sea anemone Nematostella vectensis can be isolated and incorporated into a topical formulation for continuous drug delivery. We demonstrate quantitative delivery of nicotinamide and lidocaine hydrochloride as a function of microcapsular dose or drug exposure. We also show how the released submicron tubules can be exploited as a skin penetration enhancer prior to and independently of drug application. The microcapsules are non-irritant and may offer an attractive alternative for hydrophilic transdermal drug delivery. 相似文献
297.
Maritza Leonardi Jeanett Vera Eduardo Tarifeño Marcia Puchi Violeta Morín 《Fish physiology and biochemistry》2010,36(3):757-765
We sought to provide a useful indicator of the presence of endocrine-disrupting contaminants along the marine coast of the
South Pacific using Chilean flounder (Paralichthys adspersus). In light of the lack of information on vitellogenin for this species, we induced, purified, and identified the plasma vitellogenin
of Chilean flounder inhabiting the Chilean coast. Vitellogenin (Vg) from Chilean flounder was purified by size exclusion and
ion-exchange chromatography using plasma from juvenile males induced by injecting 17β-estradiol. The Vg was detected by SDS–PAGE and Western blot analyses using an antibody against turbot (Scophthalmus maximus) vitellogenin. These analyses revealed a protein band of 205 kDa and three minor bands of 120, 90, and 68 kDa. These proteins
were identified as Vg by means of mass spectrometry (LCQ Duo ESI-IT-MS), matching sequences of tryptic peptides to known sequences
for several other fish species. The matches showed the presence of vitellogenin (VgI, VgII, Vg A and Vg B) in Chilean flounder,
similar to species such as mummichog (Fundulus heteroclitus), Japanese medaka (Oryzias latipes), and white perch (Morone americana). These results are discussed in terms of identifying Vg in Paralichthys adspersus with the antibody to turbot Vg. Moreover, we compare the molecular size of Vg from Chilean flounder (large) with that of
other flatfish species. Finally, we discuss the potential use of this molecule as a biomarker for the presence of xeno-estrogenic
compounds along the Chilean coastline. 相似文献
298.
Sofía Jones Rodrigo Calvo Melisa Celia Jazmin Rolón Germán Tettamanti David Gustavo Vera Laura Prosdocimi 《水产资源保护:海洋与淡水生态系统》2024,34(4):e4157
1. The Northern Argentine continental shelf is a sea turtle feeding ground that overlaps with important fisheries. Few studies assessed bycatch impact, especially on commercial vessels. 2. This work documents sea turtles' bycatch, fishery involved, species captured and crew actions. 3. Bycatch in four fisheries were registered at the 107 interviews to fishers conducted between 2021 and 2023, showing the urgency to research bottom trawling for demersal multi-species. Fishers frequently recognize Caretta caretta, and positive and negative practices towards animals have been documented on-board. 4. These results will help focus researches on fisheries with the greatest impact on sea turtles in the region. They also underscore the necessity for implementing commercial vessel monitoring programmes and improving on-board handling practices. 相似文献
299.
Carla Pires Irineu Batista Vera Godinho Maria Leonor Nunes 《Journal Of Aquatic Food Product Technology》2013,22(1):60-72
ABSTRACT The resulting supernatant from the isoelectric precipitation of “sawdust” from Cape hake portioning and blue whiting muscle was concentrated by ultrafiltration and the retentate spray-dried. Two main peaks corresponding to molecular weights of 15 kDa and 65 kDa were detected in the supernatant from both raw materials; in the retentate the main proteins had approximately 18 kDa and 73 kDa, and some proteins with 59 kDa were detected in the permeate. The protein content was 74.0% and 70.0% for hake by-products and blue whiting, respectively. Dried proteins had relatively low emulsifying and foaming capacity but high foaming stability and were whitish in color. Hydrophobicity and sulphydryl content were similar to those from other protein sources. 相似文献
300.
OBJECTIVE: To compare prothrombin time (PT), activated partial thromboplastin time (APTT), and fibrinogen concentration in canine blood samples collected via an indwelling IV catheter and direct venipuncture. ANIMALS: 35 dogs admitted to an intensive care unit that required placement of an IV catheter for treatment. PROCEDURES: Blood samples were collected via IV catheter and direct venipuncture at the time of catheter placement and 24 hours after catheter placement. Prothrombin time, APTT, and fibrinogen concentration were measured. RESULTS: 5 dogs were excluded from the study; results were obtained for the remaining 30 dogs. Agreement (bias) for PT was -0.327 seconds (limits of agreement, -1.350 to 0.696 seconds) and 0.003 seconds (limits of agreement, -1.120 to 1.127 seconds) for the 0- and 24-hour time points, respectively. Agreement for APTT was -0.423 seconds (limits of agreement, -3.123 to 2.276 seconds) and 0.677 seconds (limits of agreement, -3.854 to 5.207 seconds) for the 0- and 24-hour time points, respectively. Agreement for fibrinogen concentration was -2.333 mg/dL (limits of agreement, -80.639 to 75.973 mg/dL) and -1.767 mg/dL (limits of agreement, -50.056 to 46.523 mg/dL) for the 0- and 24-hour time points, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Agreement between the 2 techniques for sample collection was clinically acceptable for PT, APTT, and fibrinogen concentration at time 0 and 24 hours. It is often difficult or undesirable to perform multiple direct venipunctures in critically ill patients. Use of samples collected via an IV catheter to monitor PT and APTT can eliminate additional venous trauma and patient discomfort and reduce the volume of blood collected from these compromised patients. 相似文献