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61.
Jakab C Rusvai M Szabó Z Gálfi P Marosán M Kulka J Gál J 《Acta veterinaria Hungarica》2011,59(1):99-112
In this study, synchronous spontaneous, independent liver and gallbladder tumours were detected in a Bearded dragon (Pogona vitticeps). The multiple tumours consisted of intrahepatic cholangiocarcinoma as well as in situ adenocarcinoma and two adenomas of the gallbladder. The biliary epithelial cells and the cholangiocarcinoma showed membranous cross-immunoreactivity for claudin-7. The gallbladder epithelial cells, its adenoma and adenocarcinoma showed basolateral cross-reactivity for claudin-7. We think that the humanised anti-claudin-7 antibody is a good marker for the detection of different primary cholangiocellular and gallbladder tumours in Bearded dragons. The cholangiocytes, the cholangiocarcinoma, the endothelial cells of the liver and the epithelial cells and gallbladder tumours all showed claudin-5 cross-reactivity. The humanised anti-cytokeratin AE1-AE3 antibody showed cross-reactivity in the biliary epithelial cells, cholangiocarcinoma cells, epithelial cells and tumour cells of the gallbladder. It seems that this humanised antibody is a useful epithelial marker for the different neoplastic lesions of epithelial cells in reptiles. The humanised anti-α-smooth muscle actin (α-SMA) antibody showed intense cross-reactivity in the smooth muscle cells of the hepatic vessels and in the muscle layer of the gallbladder. The portal myofibroblasts, the endothelial cells of the sinusoids and the stromal cells of the cholangiocarcinoma and gallbladder tumours were positive for α-SMA. The antibovine anti-vimentin and humanised anti-Ki-67 antibodies did not show crossreactivity in the different samples from the Bearded dragon. 相似文献
62.
The course of the Maillard reaction between α-lactalbumin and various mono- and oligosaccharides in the solid state was studied using UPLC-ESI-TOF-MS. Individual reaction products were monitored for their degree of substitution per protein molecule (DSP). The Maillard reaction rate depended on the saccharide type and decreased when the saccharide size increased. Conjugation with charged saccharides was hindered when a specific average DSP was reached, probably resulting from electrostatic repulsion. The DSP varied between 0 and 15, and the standard deviation of the average DSP, which is a measure for product dispersity, increased to 1.9. Similar experiments were performed with a dipeptide. Relative reaction rates in these experiments were 1 for glucose, 0.28 for maltose, and 0.16 for maltotriose. Comparison of the results obtained using α-lactalbumin and the dipeptide made clear that the Maillard reaction rate is determined by a number of factors, including saccharide reactivity and lysine accessibility. 相似文献
63.
64.
Redesigning IT systems for specific user groups encompasses a lot of effort with respect to analysing and understanding user behaviour. The goal of this paper is to provide insights into patterns of behaviour of agricultural users, during the usage of a decision support system called OPTIRas™. This system aids agricultural users in their cultivar selection activities. We analyse logs resulting from OPTIRas™, and we get insights into user’s navigational patterns. We claim that the results of our analysis can be used to support the redesign of decision support systems in order to address specific agricultural users’ characteristics. 相似文献
65.
The adoption of precision farming (PF) was studied on the basis of personal interviews conducted at several agricultural exhibitions
in Germany. Between 6.65% and 11% of the interviewed farmers used PF. The majority used data collection techniques such as
GPS-based area measurement and soil sampling rather than variable rate application techniques such as site-specific sowing
and fertilising. Roughly half the farmers interviewed knew about PF. About 7–10% of them intended to start using PF in the
future. The results indicated that a large number of farmers did not even know what PF meant. In order to get more insight
into this situation, several interviews were conducted with farmers already using PF techniques. A further study in 2005 of
PF education in Germany indicated that, especially at vocational and technical schools, the subject was only covered to a
small extent although the aim was to give a better coverage in future. At higher education levels, such as at universities
and technical colleges, the teaching of PF was clearly better established. In order to promote awareness of PF among farmers,
information and teaching materials adapted to the relevant educational levels were developed and tried out at training events.
The main topics addressed were parallel tracking systems, site-specific nitrogen fertilising, yield mapping in grain production
and the use of PDAs in crop farming. Finally, preliminary survey results are presented showing how knowledge about PF can
best lead to its adoption and transfer into daily practice. 相似文献
66.
Dr. F. Hüter 《Journal of pest science》1950,23(4):49-51
Ohne Zusammenfassung 相似文献
67.
Mystery swine disease in The Netherlands: the isolation of Lelystad virus. 总被引:115,自引:0,他引:115
G Wensvoort C Terpstra J M Pol E A ter Laak M Bloemraad E P de Kluyver C Kragten L van Buiten A den Besten F Wagenaar 《The Veterinary quarterly》1991,13(3):121-130
In early 1991, the Dutch pig-industry was struck by the so-called mystery swine disease. Large-scale laboratory investigations were undertaken to search for the etiological agent. We focused on isolating viruses and mycoplasmas, and we tested paired sera of affected sows for antibodies against ten known pig viruses. The mycoplasmas M. hyosynoviae, M. hyopneumoniae, and Acholeplasma laidlawii, and the viruses encephalomyocarditis virus and porcine enterovirus types 2 and 7 were isolated from individual pigs. An unknown agent, however, was isolated from 16 of 20 piglets and from 41 of 63 sows. This agent was characterised as a virus and designated Lelystad virus. No relationship between this virus and other viruses has yet been established. Of 165 sows reportedly afflicted by the disease, 123 (75 per cent) seroconverted to Lelystad virus, whereas less than 10 per cent seroconverted to any of the other virus isolates or to the known viral pathogens. Antibodies directed against Lelystad virus were also found in pigs with mystery swine disease in England, Germany, and in the United States. We conclude that infection with Lelystad virus is the likely cause of mystery swine disease. 相似文献
68.
在一个正在寻找小公猪去势替代方法的尝试中,研究者已经提出了多项新的初步方法,绝对不会产生小公猪可能是其中一种最具创造性的方法。受孕前的性别选择正在英国和丹麦实施,不过仍有一些工作必须要做。 相似文献
69.
70.
J. J. F. M. Corten A. A. H. M. ter Huurne P. D. S. Moorhouse R. C. de Rooij 《Tropical animal health and production》1988,20(2):78-84
Summary A trypanosomiasis survey was conducted in South-West Zambia. From a total of 3,346 cattle sampled 342 cattle showed a positive trypanosomiasis parasitaemia. During the survey trypanosome species and PCV values were also recorded. With simple statistical analysis populations with higher and lower prevalence rates were differentiated. The results indicated that the Kwando River Basin Tsetse Fly Belt and the Kafue River Basin Tsetse Fly Belt infested a larger area than originally assumed and that a link-up between both belts occurred or will occur in the near future.
Prevalencia De Tripanosomiasis En Ganado En El Sudoccidente De Zambia
Resumen Se llevó a cabo una encuesta sobre la prevalencia de tripanosomiasis en el Sudoccidente de Zambia. De 3.346 animales examinados, 342 mostraron parasitémia. Durante le encuesta, se diferenciaron las especies de tripanosomas encontrados y se estimaron los hematocritos. Se diferenciaron también, mediante análisis estadísticos sensillos, las poblaciones de gando con tasas de prevalencia mayores y menores. Los resultados indican, que la cuenca del río Kwando y la del río Kafue, en donde existe la mosca tsetse, tienen una influencia mayor sobre la prevalencia de la enfermedad, que lo que originalmente se pensó y que la unión de las dos hoyas se producirá en un futuro cercano.
Prevalence De La Trypanosomose Bovine En Zambie Du Sud-Ouest
Résumé Une enquête sur la trypanosomose a été conduite dans le sud-ouest de la zambie. Sur un total de 3346 bovins examinés, 342 ont montré une parasitémie à trypanosomes. Au cours de cette enquête, on a noté les espèces de trypanosomes et les valeurs de l'hématocrite. On a pu différencier, par une méthode statistique simple, les populations à haute et basse prévalence. Les résultats indiquent que les ceintures glossiniennes des bassins, des rivières Kwando et Kafue étaient plus étendues qu'on ne le pensait antérieurement, et qu'une liaison entre les deux ceintures se produisait ou se produirait dans le futur proche.相似文献