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91.
Anders Eklund Gunnar Ågren 《Plant foods for human nutrition (Dordrecht, Netherlands)》1970,19(4):313-332
A protein concentrate has been prepared from nigerseed (Guizotia abyssinica Cass.) by a method involving extraction of the protein with NaCl-solution.The protein concentrate contains about 65% of protein (N×5.5) calculated from the dry weight, and the amino acid pattern is fairly well balanced. The chemical score is 82 calculated from the A/E values.The nutritional value of the product has been tested on young rats. These tests revealed the presence of antinutritional factors in the protein concentrate. The PER was only 1.5.It was also found that the rate of digestion by pancreatin was much slower for the protein concentrate than for casein, possibly due to enzyme resistent linkages.The protein concentrate seems to be devoid of hemagglutinin activity. Antibodies against the nug extracts could not be found.
CNU Report No. 34. 相似文献
Zusammenfassung Ein Proteinkonzentrat wurde aus Nug-Samen (Guizotia abyssinica Cass.) durch eine Methode gewonnen, die eine Extraktion des Proteins mit NaCl-Lösung einschließt.Das Proteinkonzentrat enthalt etwa 65% Protein (N x 5,5), berechnet auf das Trockengewicht. Das Aminosäuregleichgewicht ist relativ gut balanziert. Die chemical score nach den A/E Werten berechnet, beträgt 82.Der Nährwert des Produktes ist an jungen Ratten getestet worden. Diese Tests zeigten das Vorhandensein von Antinähr-Faktoren im Proteinkonzentrat. Die PER (protein efficiency ratio) betrug nur 1,5.Es wurde außerdem festgestellt, daß die Geschwindigkeit der enzymatischen Verdauung (mit Pankreatin) für das Proteinkonzentrat viel langsamer abläuft als für Casein. Dieses ist vielleicht bedingt durch Enzymresistente Bindungen.Das Proteinkonzentrat scheint von Hämagglutininaktivität frei zu sein. Es wurden keine Antikörper gegen Nug-Extrakte gefunden.
Résumé Une solution concentrée de protéine a été préparée de grains de nug (Guizotia abyssinica Cass.) par une méthode contenant l'extraction de la protéine avec la solution NaCl.La solution concentrée contient environ 65% de protéine (N X 5,5) calculée du poids sec, et le modèle des aminoacides est assez bien balancé. Le chemical score est 82 calculé des valeurs A/E. La valeur nutritive du produit a été éprouvé à de jeunes rats. Ces épreuves ont révélé la présence d'éléments antinutritives dans la solution concentrée de protéine. La PER (protein efficiency ratio) était seulement 1,5.On a aussi trouvé que la rapidité de digestion enzymatique (avec la pancréatine) pour la solution concentrée de protéine était beaucoup plus lente que pour le casein. Ceci est peut-être du à des liaisons qui résistent aux enzymes.Il semble que la solution concentrée de protéine manque d'activité hemagglutinine. On n'a pas pu trouver des anticorps dirigés contre les extraits de nug.
CNU Report No. 34. 相似文献
92.
Newquist G 《Science (New York, N.Y.)》2010,330(6004):585-7; author reply 587
93.
Thea M. Edwards Hilary D. Miller Gunnar Toft Louis J. Guillette Jr. 《Fish physiology and biochemistry》2013,39(5):1165-1180
Sixteen monthly collections of adult male Gambusia holbrooki (eastern mosquitofish) were obtained from two lakes in central Florida, USA. Lake Woodruff and Lake Apopka are 36 miles apart, but differ in several environmental parameters. Compared with Lake Woodruff, Lake Apopka is warmer, more shallow in sampling areas (particularly during drought conditions; approximately 15–90 cm in Lake Apopka versus 60–120 cm in Lake Woodruff), more turbid, and more heavily contaminated with nutrients and industrial and agricultural chemicals. Here, we present detailed information on seasonal reproduction patterns in mosquitofish in their native range and compare patterns between fish from the two lakes. Male mosquitofish were reproductively active from spring through fall. Spermatogenesis, which is regulated in part by 11-ketotestosterone, ceased in October, and fish stored spermatozoa through the winter for immediate fertilization of offspring in the spring. Compared with Lake Woodruff, fish from Lake Apopka tended to be larger and have longer gonopodia and greater gonado- and hepato-somatic indices (GSI and HSI). High GSI in Apopka fish correlated with greater spermatid production, but fewer mature spermatozoa and either the same or lower sperm counts and sperm viability. Taken together, these observations suggest that differentiation of spermatids to spermatozoa is disrupted in Apopka fish, leading to reductions in fertility in some months. Delivery of sperm to females could also be affected in Apopka fish, which exhibit lower prevalence of efferent duct tissue in the testes during the summer. 相似文献
94.
Jonsson?AndersEmail author Marzec-Schmidt?Katarzyna B?rjesson?Gunnar Wallenhammar?Ann-Charlotte 《European journal of plant pathology / European Foundation for Plant Pathology》2016,145(3):573-581
Clubroot (Plasmodiophora brassicae) is a serious soil-borne disease in brassica crops world-wide. We report on a time series of soil samples from Swedish long-term fertility trials started in 1957, 1963 and 1966, which were analyzed for the amount of P. brassicae DNA. The crop rotations included a brassica crop every 4 or 6 years. All experimental sites with a 4-year rotation of oilseed rape, except one with calcium carbonate in the soil profile, showed high (>1000 fg DNA g?1 soil) levels of P. brassicae DNA after 9, 11 and 12 rotations. In contrast, detectable levels (>5 fg DNA g?1 soil) of P. brassicae were found only at one of five sites with a 6-year rotation of spring oilseed rape. In years with high levels of P. brassicae DNA, low yield was reported and a subsequent decline in P. brassicae DNA in soil was observed. Different NPK (nitrogen/phosphorus/potassium) fertiliser regimes resulted in similar P. brassicae DNA levels. The robustness and reliability of the method applied was verified by analyses of soil from individual plots compared with a mixture of plots and by repeated analyses of selected samples, which showed that P. brassicae DNA remained stable during dry storage. 相似文献
95.
Gunnar Jacks 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2019,69(5):405-410
Land drainage in Sweden has been regulated in various laws since the Middle Ages. The lowering of lake surfaces and the ditching of wetlands has been considered a valuable task to gain cultivable land, and more recently, to promote forest growth. However, in recent years the debate surrounding drainage in forests has been a matter of considerable discussion. The dry and hot summer of 2018 has awakened new views on the subject. Monitoring has shown an exceptionally low groundwater levels countrywide. Especially the islands of Öland and Gotland have faced groundwater shortages and the groundwater levels are still low in both small and large aquifers. Drainage within forest land has lacked any scientific basis until rather recently. Still, it has been a supported activity during the twentieth century. However, this has gradually as knowledge on the activity has increased and the ecology of downstream water bodies has been considered. Today, only the rinsing of existing drainage is actively practised, and it is surrounded by a number of recommendations which are still under discussion. 相似文献
96.
Janneche Utne Skaare Gunnar Berge Stig
degaard Kari Grave 《Acta veterinaria Scandinavica》1982,23(1):16
The concentrations of methoxychlor in cow milk and plasma were determined following a cutaneous application of a non-commercial emulsion and an intravenous injection of a solution containing 5 and 1 g methoxychlor, respectively. Furthermore, some pharmacokinetic parameters were estimated and the results were evaluated toxicologically by comparison with the acceptable daily intake.Maximum concentration of methoxychlor in milk, found 2 days after dermal administration, was 0.062 ppm, decreasing to around 0.005 ppm 30 days later.From the results, a distribution volume greater than 200 times the body volume, a dermal absorption of around 1/5 of the topically applicated dose, and a half-life of 8–10 days were estimated.It was concluded that the levels in cow milk, following dermal application with an emulsion of methoxychlor did not represent any threat to human health and methoxychlor was recommended as a pesticide of choice for use on dairy cows. 相似文献
97.
Tore Sivertsen Jan T. Karlsen Gunnar Norheim Arne Frslie 《Acta veterinaria Scandinavica》1978,19(3):472
Copper absorption, liver accumulation and development of copper toxicosis in sheep are influenced by a variety of other elements, in particular molybdenum, sulphur and zinc (Underwood 1977). In a previous study on liver concentrations of copper, molybdenum and zinc in normal and copper-poisoned sheep, no direct correlation was found between the concentrations of the three metals, but molybdenum was significantly lower in the livers from sheep dead from chronic copper poisoning than in normal animals (Frøslie & Norheim 1976). 相似文献
98.
The objective of this pilot study was to compare the cytokine profile as well as cell-mediated and antibody responses of foals infected with a low inoculum of virulent Rhodococcus equi resulting in subclinical pneumonia to that of foals infected with a high inoculum resulting in severe clinical pneumonia. The mean (±SD) ratio of post-infection to pre-infection anti-R. equi IgG(T) concentration was significantly (P = 0.002) higher in foals infected with the high inoculum (195 ± 145; range 62–328) compared to foals infected with the low inoculum (3.9 ± 4.5; range 0.5–11). Similarly, mean (±SD) ratio of post-infection to pre-infection IgM concentration was significantly (P = 0.002) higher in foals infected with the high inoculum (12 ± 4.0; range 7.4–14) compared to foals infected with the low inoculum (2.5 ± 1.5; range 1.2–4.7). Proliferative responses to R. equi antigens as well as expression of mRNA for IL-2, IL-4, IL-10, and IFN-γ in BLN were not significantly different between the two groups. There was a tendency (P = 0.073) towards a higher IFN-γ/IL-4 ratio in the low inoculum group. This study demonstrates that the size of inoculum modulates the IgG subisotype response and possibly the cytokine profile of foals. 相似文献
99.
100.
Nestor R. Bottino Joseph Gennity Martha L. Lilly Eugenia Simmons Gunnar Finne 《Aquaculture (Amsterdam, Netherlands)》1980,19(2):139-148
The fatty acids of three species of shrimp from the Gulf of Mexico, white (Penaeus setiferus), brown (P. aztecus), and pink (P. duorarum), were analyzed periodically for 1 year. The fatty acid patterns of varied species of shrimp collected at the same time of the year differed very little from each other. On the other hand, a slight but distinctive seasonal variation of the fatty acid composition, irrespective of Penaeus species, was observed. Saturated fatty acids increased during the warm seasons and decreased during the cold months, while the opposite behavior was exhibited by monoenoic and polyenoic fatty acids. When the variations in fatty acid levels were compared to the temperature of the water, there was a 2-month lag period between a change in water temperature and the corresponding variation in fatty acid composition. This slow alteration of the shrimp fatty acids suggests that the changes are effected through the food chain rather than by endogenous adjustment to an alteration in water temperature.Further studies were performed in which the fatty acid patterns of pond- and laboratory-reared shrimp were compared with those of their food. Evidence was obtained confirming the significant effect of diet on the fatty acids of shrimp lipids. Shrimp incorporated certain dietary fatty acids readily but showed little ability for the conversion of C18 polyunsaturated fatty acids into C20 and C22 fatty acids of higher unsaturation. Thus, the C20 and C22 fatty acids which are essential for shrimp growth cannot be substituted in the diet by C18 precursors.Considered in toto, these experiments suggest that diet exerts a strong influence on the composition of shrimp body lipids and that, contrarily, endogenous synthesis or modification occurs to a low degree. 相似文献