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91.
Jingwen Zhou Montserrat Fuentes Jerry Davis 《Journal of Agricultural, Biological & Environmental Statistics》2011,16(4):531-553
The evaluation of physically based computer models for air quality applications is crucial to assist in control strategy selection.
Selecting the wrong control strategy has costly economic and social consequences. The objective comparison of the means and
variances of modeled air pollution concentrations with the ones obtained from observed field data is the common approach for
the assessment of model performance. One drawback of this strategy is that it fails to calibrate properly the tails of the
modeled air pollution distribution. Improving the ability of these numerical models to characterize high pollution events
is of critical interest for air quality management. 相似文献
92.
Two sizes of rainbow trout [170 (4), 91 (3) g] were progressively transferred to seawater in January 1995 using three steps of 9, 20 and 28. Na+-K+-ATPase activity in gills, intestine and kidney, and plasma sodium and magnesium levels were assessed in response to changed external salinity. Gradual transfer to seawater had a stimulatory effect on gill and intestinal Na+-K+-ATPase activities after the transfer to 28, while its activity remained unchanged in the kidney. Plasma sodium content was not modified, while magnesium levels increased in response to increased external salinity. The size-dependent response to seawater transfer described by other authors was not detected in our experiments. The results are discussed in terms of long-term adaptation to seawater. 相似文献
93.
J. Iglesias L. Fuentes J. Sánchez J.J. Otero C. Moxica M.J. Lago 《Aquaculture (Amsterdam, Netherlands)》2006,261(2):817-822
Different assays related to the first feeding of Octopus vulgaris Cuvier, 1797 are compiled in this paper. They include: age at initial feeding age, prey size selection and optimal density, attack timing after feeding, and effect of dose number on the number of captures. Prey capture and ingestion processes were also analysed. Food supplied was cultured Artemia sp. Each assay lasted 15 min.Although paralarvae already start to feed on the hatching day (day 0), it is during day 2 when a greater number of attacks is recorded (81.7 ± 14.7% paralarvae attack). They mainly prefer (significance level α = 0.05) large Artemia, 1.4 ± 0.4 mm (77.0 ± 5.6% of the total attacks) than small Artemia, 0.8 ± 0.1 mm (23.0 ± 5.6%). There is also a slight predilection for the lowest Artemia concentration (33.3 ±12.6% paralarvae attack in a 0.1 Artemia ml− 1 density, opposite 16.7 ± 7.6 and 18.3 ± 7.6% in densities of 0.5 and 1 Artemia ml− 1 respectively). The greatest predatory activity is recorded during the first 5 min after food is supplied (72.2 ± 25.5%). An increase in the predatory activity was also observed when food was distributed in several doses instead of a single dose (75.0 ± 10.0% and 46.7 ± 17.6% respectively). It was proved for the first time that paralarvae completely ingest their preys (including their exoskeletons), in this case Artemia. Time needed for their total ingestion ranges between 4 and 10 min. 相似文献
94.
J. Iglesias J.J. Otero C. Moxica L. Fuentes F.J. Sánchez 《Aquaculture International》2004,12(4-5):481-487
This paper shows innovating results on Octopus vulgaris Cuvier 1797 growth under culture conditions during the whole life cycle. Experiments were conducted at the Spanish Institute of Oceanography of Vigo (Spain). Using mean water temperature of 22.5°C, salinity of 35‰ and adult Artemia (1–4 mm of total length) along with a diet complement of Maja squinado zoeae as living prey, it was possible to obtain a 31.5% paralarval survival at day 40 after hatching. At this age, paralarvae had reached a dry weight of 9.5 mg, 23 suckers per arm, and they began the settlement process. First results on juvenile growth showed that they reached 0.5–0.6 kg at the age of 6 months after hatching, and 2 months later, they attained weights ranging between 1.4 and 1.8 kg. Mean temperature of the ongrowing process was 18°C. 相似文献
95.
Drinking in freshwater juvenile salmon was investigated in response to vasodilation by sodium nitroprusside (SNP), a nitric oxide donor, which significantly increased blood vessel diameter in Atlantic salmon alevins. Atlantic salmon fry (1–3 g), as previously shown, drank at a significant rate in fresh water which doubled to about 1.2 ml kg–1 h–1 following injection of SNP (100 mol kg–1), through dilation of body vasculature and activation of a vasoconstrictive mechanism, the endogenous renin angiotensin system (RAS). This response was 50% inhibited by injection of about 100 mg kg–1 enalapril. Fry increased drinking in response to SNP administered in the water, though the concentration required for maximal response, 1.6 mmol l–1, was much greater than for injected SNP; this response was also inhibited by enalapril injection. Possible involvement of the gill vasculature and branchial osmoreceptors or baroreceptors in control of the drinking response is discussed. 相似文献
96.
97.
J. E. Castillo L. López-Bellido E. J. Fernández M. Fuentes F. J. López 《The Journal of Horticultural Science and Biotechnology》2013,88(6):867-879
SummaryThe establishment of the optimum plant population has been shown to be one of the most crucial determinants of the marketable yield of bulbous crops. This study was conducted to determine the best plant arrangements for maximum yields and maximum bulb quality in rainfed garlic (Allium sativum L.) grown under Mediterranean conditions. The effects of row width and plant spacing on the yield and quality of the two cvs. Morado de Pedroneras and Germidour, were investigated on Córdoba, Spain, in Vertisol Chromoxerert soil. In 1987–1988, a wet growing season, higher yields and higher bulb quality were obtained than in 1988–1989; cv. Germidour yielded more per unit of land area of higher quality bulbs during both seasons. Narrow row width and/or narrow plant spacing resulted in higher values of dry matter, LAI, LAD, CGR and yield, whereas wide row spacing and/or wide plant spacing resulted in higher ware-sized bulb yield. LAD was closely related to yield (r2 = 0.96**) and total dry matter (r2 = 0.90**). Mean leaf surface was affected by plant density and climatic conditions and showed a high positive relationship (r2 = 0.90**) with the percentage of Extra grade of bulbs (>50 mm). As a result of this study, a row width of 45–60 cm with plant spacing of 12–16 cm is recommended for cv. Germidour and 45 × 16 cm for cv. Morado, to maximize the proportion of high-quality yield under Mediterranean rainfed cropping systems. 相似文献
98.
99.
As there was no consensus on the presence or absence of Aphis (Toxoptera) citricidus (Kirkaldy) in Chile, a meticulous literature survey has been carried out to clarify the issue. From this survey, it can be concluded that A. (T.) citricidus is not present in Chile, that it has never been cited as present from first‐hand information/observations in this country, and that all available Chilean records of this species are due to old (and now abandoned) taxonomic interpretations or poor transmission of information. 相似文献
100.
Marta Fuentes Roberto Baigorri Gustavo González-Gaitano José María García-Mina 《Journal of Soils and Sediments》2018,18(4):1389-1399