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61.
This study was carried out to evaluate the effects of the sperm cell dose and semen backflow on the pregnancy rate and number of embryos of sows inseminated once at 0-24 h before ovulation, using an intrauterine technique. The results were analysed from a total of 211 sows assigned to three groups inseminated with doses of 0.25 x 10(9) (T1), 0.5 x 10(9) (T2) and 1.0 x 10(9) (T3) spermatozoa. Semen backflow was observed in 95% of the females (143/151) evaluated for this purpose. The percentage of semen backflow is close to two-third of the volume and the percentage of sperm is around 15% of the infused sperm dose. Intrauterine insemination can be successfully performed provided that at least 0.5 billion of sperm cell dose is infused at an interval of 0-24 h before ovulation.  相似文献   
62.
Six new pesticide metal complexes were synthesised, characterised and evaluated for controlled release by chemical and bioassay methods. Chemical assay and bioassay data demonstrate the increased persistence and increased shelf life of the pesticides upon complexation.  相似文献   
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64.
The presentation, treatment and outcomes of 33 ingluvial fibrous foreign bodies in cockatiels (Nymphicus hollandicus) are described. Vomiting, lethargy and weight loss were the most common presenting signs. Diagnosis was made on palpation of a mass in the crop (ingluvies). Both surgical and non‐surgical treatment regimens were evaluated. The overall mortality rate was 33%, suggesting fibrous materials are not safe for cockatiels to groom or ingest and should not be offered as cage accessories.  相似文献   
65.
Sorghum head bug, Calocoris angustatus Lethiery is one of the most important pests of grain sorghum in India. Head bug damage increases the severity of grain molds, which renders the grain unfit for human consumption. Therefore, we studied the gene action for resistance to head bugs and grain molds in a diverse array of male-sterile lines and testers in a line × tester mating design under natural infestation. Mean squares for parents, parents vs crosses, lines, testers, and lines × testers were significant for head bug damage and grain mold severity. General combining ability (GCA) effects were significant and negative for ICSA 88019 for head bug damage, and ICSA 88019 and ICSA 88020 for grain molds (except for ICSA 88020 in 1993). General combining ability effects were positive for ICSA 42 and 296 A. GCA effects of lines and testers for head bug damage and grain mold severity were in the same direction (+ve or −ve). Head bug damage in the grain was significantly correlated with grain mold severity. Testers IS 8891, IS 15107, and TAM 2566 (with colored grain and less susceptibility to molds) produced mold-resistant hybrids in combination with all the male-sterile lines, while the reverse was true in the case of Swarna and ICSV 112. Resistance to head bugs showed dominance to partial dominance type of gene action, while in the case of grain molds, it showed dominance to over dominance. Resistance to these pests is governed by both additive and nonadditive types of gene action. The implications of these results are discussed in relation to need for crop improvement in sorghum. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
66.
Reddy  M. Sudhakara  Satyanarayana  T. 《New Forests》1998,16(3):273-279
Micropropagated plantlets of Eucalyptus tereticornis at the root initiation stage were inoculated in vitro with Amanita murina, Hysterangium incarceratum, Laccaria laccata, Pisolithus tinctorius (3 isolates), Scleroderma cepa and S. flavidum in order to select the most compatible ectomycorrhizal partner. H. incarceratum and the two Scleroderma species did not form mycorrhizas with E. tereticornis. Two local isolates of P. tinctorius formed significantly more mycorrhizas than the other isolates tested. Plantlets with mycorrhizas formed by one of the local isolates of P. tinctorius were transplanted to the nursery where their growth significantly exceeded that of non-mycorrhizal plants.  相似文献   
67.
Central Greenland ice cores provide evidence of abrupt changes in climate over the past 100,000 years. Many of these changes have also been identified in sedimentary and geochemical signatures in deep-sea sediment cores from the North Atlantic, confirming the link between millennial-scale climate variability and ocean thermohaline circulation. It is shown here that two of the most prominent North Atlantic events-the rapid warming that marks the end of the last glacial period and the Bolling/Allerod-Younger Dryas oscillation-are also recorded in an ice core from Taylor Dome, in the western Ross Sea sector of Antarctica. This result contrasts with evidence from ice cores in other regions of Antarctica, which show an asynchronous response between the Northern and Southern Hemispheres.  相似文献   
68.
Summary

IBA-treated cuttings rooted only when prepared fom bark-ringed shoots. The response to ringing declined with increasing age of the tree. However, on marcotting, the ringed shoots of four year old trees showed more and earlier rooting.  相似文献   
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70.
Subsurface pipe and open drainage systems were installed in 8 and 5 ha area, respectively in farmers fields at Konanki pilot area in Nagarjuna Sagar project right canal command in India in the year 1999 to combat the problems of waterlogging (depth to water table, 0–3.7 m), salinity and sodicity (ECe, 1.3–18.6 dS/m; pH, 7.2–10.0 and ESP, 14.1–54.6). Two types of envelope materials, nylon mesh and geo-textile were used and two spacings of 30 m (design spacing) and 60 m (double the design spacing) were adopted for the pipe drainage system. The analysis of discharge data from the individual pipe drains revealed that among both the spacings, the drains enveloped with geo-textile performed better (0.45–1.85 mm/day), when compared with those enveloped with nylon mesh (0.25–0.86 mm/day). The effectiveness of drainage systems in the control of waterlogging at the pilot area has been monitored through a network of 61 observation wells. The groundwater table, which used to be almost at the ground surface during the main crop season (October–February) before installation of drainage systems, could be lowered by 0.2–0.35 m due to the installation of drainage systems. A total of 50.4 (@ 6.3 tons/ha) and 115.6 tons (@ 23.1 tons/ha) of salts have been disposed through pipe and open drainage systems, respectively during the period of 3 years (1999–2002).  相似文献   
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