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41.
The objective of this study was to optimize recovery and cryopreservation of epididymal sperm from plains bison, as a model for wood bison. In Phase 1, cauda epididymides were recovered from bison (n = 14) immediately after slaughter, minced and incubated in Sp-TALPH buffer for 3 h at 36°C. The resulting sperm suspensions were cryopreserved in Triladyl® , using a protocol for bovine semen. In Phase 2, epididymal sperm were cryopreserved in either Triladyl® or Andromed® . The mean (±SD) estimated number of sperm recovered was 468 ± 207 × 106 . There was an increase (p < 0.05) in the proportion of sperm with normal morphology between initial recovery and after extension (52.4 ± 4.6 vs 69.7 ± 2.4%), with a concurrent decrease (p < 0.05) in the proportion of sperm with distal droplets. Median values for progressively motile sperm in post-thaw samples (60%) were lower (p < 0.05) than that after extension or after chilling (70% for both). The mean percentages of viable sperm and of sperm with an intact acrosome were lower (p < 0.05) for frozen-thawed samples (38.7 ± 2.8 and 85.2 ± 1.1) compared with extended (66.2 ± 2.2 and 92.4 ± 0.9) or chilled (63.7 ± 2.5 and 90.0 ± 1.0) samples. Rates of cleavage, morulae and blastocyst production were not significantly different for chilled (70.9, 38.7 and 8.0%) vs post-thaw sperm (73.0, 46.0 and 6.3%). There was no significant difference between extenders for most sperm characteristics. In conclusion, we developed a functional protocol for the recovery and cryopreservation of epididymal sperm from plains bison, which may have implications for the genetic preservation of wood bison. 相似文献
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LC Padilha PPM Teixeira EA Pires‐Buttler M Apparício TF Motheo PAP Savi EYO Nakaghi AE Alves WRR Vicente 《Reproduction in domestic animals》2014,49(2):243-248
The success of embryo production in vitro depends upon the use of an efficient oocyte retrieval technique, and the best results have been obtained by laparoscopic aspiration. The aim of this study was to evaluate the effect of consecutive sessions of follicular aspiration on the quantity, quality and in vitro maturation competence of oocytes obtained from ewes subjected to hormonal stimulation. Six Santa Ines ewes underwent nine sessions of follicular aspiration by laparoscopy with a 7‐day interval between sessions, totalling 56 aspirations. After 24 h of culture, oocytes were stained and classified according to the stage of nuclear and cytoplasmic maturation. Oocyte retrieval rate was 61.4 ± 2%, resulting in a total of 249 oocytes. No significant variation was observed between sessions (p > 0.05). The average number of oocytes retrieved from each ewe was 6.4 ± 2 per session and 42 ± 4 in total. No significant difference was observed between the frequencies of the different stages of nuclear maturation: 32.72% mature, 40.74% immature and 26.54% degenerated/indeterminate oocytes; however, a significant difference was observed between the frequencies of the different stages of cytoplasmic maturation: 10.7% mature, 73.25% immature and 16.05% degenerated/indeterminate oocytes. No significant difference was observed in nuclear or cytoplasmic maturation between the weeks of procedure. We conclude that after nine consecutive sessions of follicular aspiration, the quantity and quality of retrieved oocytes remained unchanged as well as the levels of nuclear and cytoplasmic maturation obtained, demonstrating the viability of this technique for repetitive follicular aspirations on the same donor. 相似文献
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Getchell RG Groocock GH Schumacher VL Grimmett SG Wooster GA Bowser PR 《Journal of aquatic animal health》2007,19(4):226-233
The use of quantitative polymerase chain reaction (QPCR) to test for largemouth bass virus (LMBV) was evaluated during a challenge experiment in which largemouth bass Micropterus salmoides were immersed in the type strain of LMBV. The real-time PCR and cell culture methods were both used to measure LMBV present in the inoculum. Additional samples tested by QPCR included gill, gonad, kidney, liver, mucus, spleen, and swim bladder. A plasmid clone containing a 248-base pair (bp) fragment of the major capsid protein gene (MCP*) was serially diluted and used as a standard to quantify the number of LMBV DNA copies present in the samples tested. A 62-bp fragment of DNA located in MCP* was amplified in the real-time PCR assay. This work has demonstrated the value of the QPCR assay in LMBV surveys. 相似文献
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Kosoff RE Chen CY Wooster GA Getchell RG Clifford A Craigmill AL Bowser PR 《Journal of aquatic animal health》2007,19(2):109-115
Nile tilapia Oreochromis niloticus, summer flounder Paralichthys dentatus, and walleyes Sander vitreus were treated with Romet-30 (PHARMAQ AS, Oslo, Norway) via a medicated ration at 50 mg Romet-30 kg fish body weight(- 1) d(-1) for 10 d to compare the elimination kinetics of the test substance. This study was part of a larger effort to develop a species grouping concept for the labeling of therapeutic compounds for cultured fishes. The fish tests were conducted at the ideal water temperature for each species and at 5 degrees C lower than the ideal temperature except for summer flounder, which would not feed at the lower temperature of 15 degrees C. Test temperatures were 30 degrees C and 25 degrees C for Nile tilapia, 20 degrees C and 17 degrees C for summer flounder, and 25 degrees C and 20 degrees C for walleyes. Neither component of Romet-30 (sulfadimethoxine and ormetoprim) could be detected in samples of the edible portion of walleyes (muscle plus skin) collected at day 10 posttreatment or thereafter. In studies with summer flounder, only one fish had a detectable concentration of either component on day 21 or thereafter. Elimination of Romet-30 by Nile tilapia was extremely rapid. The limited number of Nile tilapia with detectable sulfadimethoxine or ormetoprim during the posttreatment period prevented the determination of elimination half-life or elimination in this species. 相似文献
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LC Venema JWG Wildoer JW Janssen SJ Tans HLJT Tuinstra LP Kouwenhoven C Dekker 《Science (New York, N.Y.)》1999,283(5398):52-55
Carbon nanotubes provide a unique system for studying one-dimensional quantization phenomena. Scanning tunneling microscopy was used to observe the electronic wave functions that correspond to quantized energy levels in short metallic carbon nanotubes. Discrete electron waves were apparent from periodic oscillations in the differential conductance as a function of the position along the tube axis, with a period that differed from that of the atomic lattice. Wave functions could be observed for several electron states at adjacent discrete energies. The measured wavelengths are in good agreement with the calculated Fermi wavelength for armchair nanotubes. 相似文献
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