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排序方式: 共有167条查询结果,搜索用时 31 毫秒
81.
82.
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
83.
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
84.
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
85.
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
86.
A Brabon R Labens A Ramachandran AJ Dart BA Dowling 《Australian veterinary journal》2023,101(8):302-307
Four adult horses with histories of moderate abdominal pain and inappetence were diagnosed with delayed gastric emptying and gastric impaction attributed to pyloroduodenal obstruction (three cases) or duodenitis (one case). A stapled side-to-side gastrojejunostomy was performed on all horses. Two horses returned to work and survived ≥3 years. One horse was euthanased 6 months post-surgery due to recurrent abdominal pain, and one was found dead 5 months postsurgery after an unattended foaling. 相似文献
87.
88.
Raphael Mainiero Marian Kazda Iris Schmid 《European Journal of Forest Research》2010,129(6):1001-1009
Fine root dynamics in mono-specific stands of mature Fagus sylvatica L. and Picea abies Karst. was studied from December 2003 to December 2004 in a stand in Southern Germany. Minirhizotrons were used to draw between
species comparisons concerning fine root (≤1 mm) longevity and temporal patterns of fine root dynamics (growth and mortality)
as related to seasonal changes in soil water content and soil temperature. In F. sylvatica, median fine root longevity from early seasonal to late-seasonal cohorts was low (77 days). Fine root dynamics scaled positively
with seasonal changes in soil water and temperature indicating accelerated fine root turnover during favourable soil conditions.
In contrast, fine root longevity in P. abies (273 days) was significantly higher when compared to F. sylvatica and increased from early seasonal to late-seasonal cohorts. Fine root dynamics in P. abies did not correlate with soil environmental conditions. Rather a large proportion of new fine roots occurred during the dry
season in superficial soil layers. The data suggest species inherent patterns of fine root longevity and temporal patterns
of fine root dynamics. 相似文献
89.
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
90.