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排序方式: 共有163条查询结果,搜索用时 15 毫秒
81.
Wagner Rodrigo de Souza Nelson Geraldo de Oliveira Felipe Vinecky Ana Paula Ribeiro Marcos Fernando Basso Raphael Augusto das Chagas Noqueli Casari Brbara Andrade Dias Brito da Cunha Karoline Estefani Duarte Thaís Ribeiro Santiago Polyana Kelly Martins Carlos Eduardo Aucique‐Perez Sílvio Carlos Cristofoletti Júnior Alexandre Lima Nepomuceno Carlos Antnio Ferreira de Sousa Adilson Kenji Kobayashi Kazuo Nakashima Kazuko Yamaguchi‐Shinozaki Hugo Bruno Correa Molinari 《Journal of Agronomy and Crop Science》2019,205(6):545-553
82.
AFC de Andrade RP de Arruda ECC Celeghini J Nascimento SMMK Martins CF Raphael AS Moretti 《Reproduction in domestic animals》2007,42(2):190-194
The purpose of this study was to validate a technique for simultaneous evaluation of the plasma, acrosomal and mitochondrial membranes in boar spermatozoa, using an association of fluorescent probes: Propidium iodide (PI), fluorescein isothiocyanate-conjugated Pisum sativum agglutinin (FITC-PSA) and JC-1. Three ejaculates from each of four different boars, all showing motility >or=80% and abnormal morphology 相似文献
83.
This short report summarises data on the prevalence of high psychological distress in horse industry participants during the 2007 Australian equine influenza (EI) outbreak and the statistical analysis undertaken to identify the factors associated with this high psychological distress. In addition, follow-up data collected 1 year later are reported briefly. 相似文献
84.
S. A. Cushman M. G. Raphael L. F. Ruggiero A. S. Shirk T. N. Wasserman E. C. O’Doherty 《Landscape Ecology》2011,26(8):1137-1149
In mobile animals, movement behavior can maximize fitness by optimizing access to critical resources and minimizing risk of
predation. We sought to evaluate several hypotheses regarding the effects of landscape structure on American marten foraging
path selection in a landscape experiencing forest perforation by patchcut logging. We hypothesized that in the uncut pre-treatment
landscape marten would choose foraging paths to maximize access to cover types that support the highest density of prey. In
contrast, in the post-treatment landscapes we hypothesized marten would choose paths primarily to avoid crossing openings,
and that this would limit their ability to optimally select paths to maximize foraging success. Our limiting factor analysis
shows that different resistant models may be supported under changing landscape conditions due to threshold effects, even
when a species’ response to landscape variables is constant. Our results support previous work showing forest harvest strongly
affects marten movement behavior. The most important result of our study, however, is that the influence of these features
changes dramatically depending on the degree to which timber harvest limits available movement paths. Marten choose foraging
paths in uncut landscapes to maximize time spent in cover types providing the highest density of prey species. In contrast,
following landscape perforation by patchcuts, marten strongly select paths to avoid crossing unforested areas. This strong
response to patch cutting reduces their ability to optimize foraging paths to vegetation type. Marten likely avoid non-forested
areas in fragmented landscapes to reduce risk of predation and to benefit thermoregulation in winter, but in doing so they
may suffer a secondary cost of decreased foraging efficiency. 相似文献
85.
Meghann Lustgarten W. Rich Redding Raphael Labens Michel Morgan Weston Davis Gabriela S. Seiler 《Veterinary radiology & ultrasound》2014,55(1):92-101
Tendon and ligament injuries are common causes of impaired performance in equine athletes. Gray‐scale ultrasonography is the current standard method for diagnosing and monitoring these injuries, however this modality only provides morphologic information. Elastography is an ultrasound technique that allows detection and measurement of tissue strain, and may provide valuable mechanical information about equine tendon and ligament injuries. The purpose of this study was to determine the feasibility, reproducibility, and repeatability of elastography; and to describe elastographic characteristics of metacarpal tendons in sound horses. Nineteen legs for 17 clinically sound horses without evidence of musculoskeletal pathology were included. Elastographic images of the superficial and deep digital flexor tendons and the branches of the suspensory ligament (tendon of the interosseous muscle) were described quantitatively and qualitatively. There was no statistically significant difference between operators (P = 0.86) nor within operators (P = 0.93). For qualitative assessments, reproducibility (0.46) was moderate and repeatability (0.78) was good. Similar to human Achilles tendons, equine tendons were classified as predominantly hard using elastography. There was no statistically significant difference in stiffness of the flexor tendons (P = 0.96). No significant difference in stiffness was found with altered leg position during standing (P = 0.84) and while nonweight bearing (P = 0.61). The flexor tendons were softer when imaged in longitudinal versus transverse planes (P < 0.01) however, the suspensory branches were not (P = 0.67). Findings supported future clinical application of elastography as a noninvasive “stall‐side” imaging modality for evaluation of the tendons and ligaments of the distal forelimb in horses. 相似文献
86.
Coale KH Johnson KS Chavez FP Buesseler KO Barber RT Brzezinski MA Cochlan WP Millero FJ Falkowski PG Bauer JE Wanninkhof RH Kudela RM Altabet MA Hales BE Takahashi T Landry MR Bidigare RR Wang X Chase Z Strutton PG Friederich GE Gorbunov MY Lance VP Hilting AK Hiscock MR Demarest M Hiscock WT Sullivan KF Tanner SJ Gordon RM Hunter CN Elrod VA Fitzwater SE Jones JL Tozzi S Koblizek M Roberts AE Herndon J Brewster J Ladizinsky N Smith G Cooper D Timothy D Brown SL Selph KE Sheridan CC Twining BS 《Science (New York, N.Y.)》2004,304(5669):408-414
The availability of iron is known to exert a controlling influence on biological productivity in surface waters over large areas of the ocean and may have been an important factor in the variation of the concentration of atmospheric carbon dioxide over glacial cycles. The effect of iron in the Southern Ocean is particularly important because of its large area and abundant nitrate, yet iron-enhanced growth of phytoplankton may be differentially expressed between waters with high silicic acid in the south and low silicic acid in the north, where diatom growth may be limited by both silicic acid and iron. Two mesoscale experiments, designed to investigate the effects of iron enrichment in regions with high and low concentrations of silicic acid, were performed in the Southern Ocean. These experiments demonstrate iron's pivotal role in controlling carbon uptake and regulating atmospheric partial pressure of carbon dioxide. 相似文献
87.
Mari Yotsu-Yamashita Yuka Abe Yuta Kudo Raphael Ritson-Williams Valerie J. Paul Keiichi Konoki Yuko Cho Masaatsu Adachi Takuya Imazu Toshio Nishikawa Minoru Isobe 《Marine drugs》2013,11(8):2799-2813
Even though tetrodotoxin (TTX) is a widespread toxin in marine and terrestrial organisms, very little is known about the biosynthetic pathway used to produce it. By describing chemical structures of natural analogs of TTX, we can start to identify some of the precursors that might be important for TTX biosynthesis. In the present study, an analog of TTX, 5,11-dideoxyTTX, was identified for the first time in natural sources, the ovary of the pufferfish and the pharynx of a flatworm (planocerid sp. 1), by comparison with totally synthesized (−)-5,11-dideoxyTTX, using high resolution ESI-LC-MS. Based on the presence of 5,11-dideoxyTTX together with a series of known deoxy analogs, 5,6,11-trideoxyTTX, 6,11-dideoxyTTX, 11-deoxyTTX, and 5-deoxyTTX, in these animals, we predicted two routes of stepwise oxidation pathways in the late stages of biosynthesis of TTX. Furthermore, high resolution masses of the major fragment ions of TTX, 6,11-dideoxyTTX, and 5,6,11-trideoxyTTX were also measured, and their molecular formulas and structures were predicted to compare them with each other. Although both TTX and 5,6,11-trideoxyTTX give major fragment ions that are very close, m/z 162.0660 and 162.1020, respectively, they are distinguishable and predicted to be different molecular formulas. These data will be useful for identification of TTXs using high resolution LC-MS/MS. 相似文献
88.
A. Raphael Stern Ruth Ben-Arie 《The Journal of Horticultural Science and Biotechnology》2013,88(6):943-948
Summary‘Red Delicious’, the main apple cultivar grown in Israel, and ‘Jonathan’, grown on a smaller scale, are prone to substantial pre-harvest drop. Spraying both cultivars with the synthetic auxin 3,5,6-trichloro-2-pyridyl-oxyacetic acid (3,5,6-TPA) reduced pre-harvest fruit drop and increased yield. Application of 40 mg l–1 3,5,6-TPA 2 weeks before anticipated harvest (WBH), or 30 mg l–1 3,5,6-TPA at 4 and 2 WBH gave the best results, and were as effective as 2,4,5-trichloro-phenoxypropionic acid (2,4,5-TP) which was the commercial product commonly in use until being withdrawn. There were no negative effects on fruit quality at harvest, or during 8 months of storage. Therefore 3,5,6-TPA can be recommended for routine use on ‘Red Delicious’ and ‘Jonathan’ apples in Israel. 相似文献
89.
90.
Rabelo L Monteiro N Serquiz R Santos P Oliveira R Oliveira A Rocha H Morais AH Uchoa A Santos E 《Marine drugs》2012,10(4):727-743
Cancer represents a set of more than 100 diseases, including malignant tumors from different locations. Strategies inducing differentiation have had limited success in the treatment of established cancers. Marine sponges are a biological reservoir of bioactive molecules, especially lectins. Several animal and plant lectins were purified with antitumor activity, mitogenic, anti-inflammatory and antiviral, but there are few reports in the literature describing the mechanism of action of lectins purified from marine sponges to induce apoptosis in human tumor cells. In this work, a lectin purified from the marine sponge Cinachyrella apion (CaL) was evaluated with respect to its hemolytic, cytotoxic and antiproliferative properties, besides the ability to induce cell death in tumor cells. The antiproliferative activity of CaL was tested against HeLa, PC3 and 3T3 cell lines, with highest growth inhibition for HeLa, reducing cell growth at a dose dependent manner (0.5-10 μg/mL). Hemolytic activity and toxicity against peripheral blood cells were tested using the concentration of IC(50) (10 μg/mL) for both trials and twice the IC(50) for analysis in flow cytometry, indicating that CaL is not toxic to these cells. To assess the mechanism of cell death caused by CaL in HeLa cells, we performed flow cytometry and western blotting. Results showed that lectin probably induces cell death by apoptosis activation by pro-apoptotic protein Bax, promoting mitochondrial membrane permeabilization, cell cycle arrest in S phase and acting as both dependent and/or independent of caspases pathway. These results indicate the potential of CaL in studies of medicine for treating cancer. 相似文献