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31.
Liu PT Stenger S Li H Wenzel L Tan BH Krutzik SR Ochoa MT Schauber J Wu K Meinken C Kamen DL Wagner M Bals R Steinmeyer A Zügel U Gallo RL Eisenberg D Hewison M Hollis BW Adams JS Bloom BR Modlin RL 《Science (New York, N.Y.)》2006,311(5768):1770-1773
In innate immune responses, activation of Toll-like receptors (TLRs) triggers direct antimicrobial activity against intracellular bacteria, which in murine, but not human, monocytes and macrophages is mediated principally by nitric oxide. We report here that TLR activation of human macrophages up-regulated expression of the vitamin D receptor and the vitamin D-1-hydroxylase genes, leading to induction of the antimicrobial peptide cathelicidin and killing of intracellular Mycobacterium tuberculosis. We also observed that sera from African-American individuals, known to have increased susceptibility to tuberculosis, had low 25-hydroxyvitamin D and were inefficient in supporting cathelicidin messenger RNA induction. These data support a link between TLRs and vitamin D-mediated innate immunity and suggest that differences in ability of human populations to produce vitamin D may contribute to susceptibility to microbial infection. 相似文献
32.
Differences in metabolism (enzyme activities, metabolites) between diploid and triploid Salmo trutta f. lacustris were investigated under acclimation and stress conditions. Under acclimation conditions enzyme activities differed for 35% of the 27 investigated key regulatory enzymes and temperature optima for 23%. Muscle and liver metabolites related to energy metabolism and diagnostic indices of blood serum were similar, with exception of acetyl‐CoA being increased in triploids. Metabolic rate was lower and gill ventilation rate higher in triploids in comparison with diploids. During the tested stress situations (24 hr endurance swimming, 3 hr exposure to hypoxia in water with 32% oxygen saturation) muscle and liver glycogen decreased and serum and muscle lactate increased in both ploidy levels. Specifically, for triploids muscle adenylate energy charge and phosphocreatine levels decreased after endurance swimming and muscle and liver adenylate energy charge after exposure to hypoxia. Acetyl‐CoA increased in triploids during both stress situations. In summary, there existed differences in metabolism between the two ploidy levels and the energy metabolism of triploids was less balanced under stress. 相似文献
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34.
Pichner R Sander A Steinrück H Gareis M 《Berliner und Münchener tier?rztliche Wochenschrift》2005,118(7-8):321-325
In order to assess the relevance of horses as a possible reservoir of Salmonella and Shigatoxin-producing Escherichia coli (STEC), 400 samples of horse faeces and 100 samples of horse meat products were examined by PCR-screening methods. Salmonella enterica was not found in any of the samples. One faeces-sample and one horse meat product were proved to be STEC positive. The STEC-strain from faecal origin belonged to the serotype 0113:H21 and had the stx 2c gene and the enterohemolysin gene. The STEC-strain isolated from a horse meat product had the serotype O87:H16 and the stx 2d gene. The results indicate a very low risk for human to get a Salmonella- or EHEC- infection from horses in Germany. 相似文献
35.
Van Sinh Nguyen Hung Manh Nguyen Anika Klotzbücher Doris Vetterlein Thimo Klotzbücher Reinhold Jahn Janina Schneiker Manfred Türke Oliver Fried Erwin Bergmeier Cornelia Sattler Josef Settele 《Paddy and Water Environment》2018,16(2):353-358
Two major human-made problems in rice production systems in the north of Vietnam concern the low plant-available silicon content of soils and the low biodiversity. The results of the LEGATO project suggest a change to an environmentally friendly rice production system that will help to recover biodiversity. We propose here a framework for a demonstration and dissemination model that will be exemplary for the farmers once it has been successfully realized. We advocate local-option models in different districts to demonstrate to farmers. The methods should be adapted to local and ecoregional differences in climate and land-use tradition, and they explicitly take into account soil care, organic fertilizer, manual weeding, native nectar-rich plant bunds, manual pest snail collection, hymenopteran nesting aids, and biodiversity and yield monitoring. 相似文献
36.
37.
Johannes Breidenbach Sonia M. Ortiz Manfred Reich 《European Journal of Forest Research》2010,129(5):813-823
Several TerraSAR-X satellite images acquired in high resolution spotlight mode with different polarisations for two study
sites in southern Germany were used to distinguish forest from other land cover classes (agriculture, built-up, water bodies)
using logistic regression models. In general, we observed that the mean and particularly the standard deviation of the backscatter
were viable measures to discriminate land cover classes. Both measures were lowest for water bodies and highest for built-up
areas, with agricultural areas and forest in intermediate positions. Trees outside forest were not differentiable from forest
with the applied method. The HH-polarised image was better suited for a classification of built-up areas, whereas the VV-polarised
image was more appropriate when classifying agricultural areas. Consequently, the combination of the two differently polarised
images leads to a significantly better model. Since forests in one study area were generally found on steeper slopes in comparison
to other land cover classes, the inclusion of terrain slope further improved the classification, which resulted in an overall
accuracy of 92–95%. Systematic differences in the parameter values of the explanatory variables for one class between the
study areas may be caused by differing class probabilities. Thus, transferring the model of one study area to the image of
another resulted in a 7–9% loss of accuracy. 相似文献
38.
Tzvetan Zlatanov Ivaylo Velichkov Manfred J. Lexer Tomislav Dubravac 《New Forests》2010,40(3):289-303
To study the regeneration dynamics in mature black pine (Pinus nigra Arn.) plantations in the Middle Balkan Range, Bulgaria, a total of 48 research plots (sized 0.1 ha) were established; 26
plots were established in the foothills of the mountains (foothill zone) and 22 in the main massive (mountainous zone). Pine
overstorey as well as advance regeneration in subplots were recorded. Analysis of variance and regression analysis showed
that in general relative stand basal area (RSBA) was the most important predictor of deciduous advance regeneration density,
top height as well as age span of the regeneration layer. In the mountainous zone soil depth (SD) and the presence of mature
deciduous trees (MDT) explained a significant amount of the variation in regeneration features. Lower RSBA induced by earlier
thinnings resulted in higher regeneration density, larger top heights and wider age span of deciduous species. Under the pine
canopy oak regeneration can persist longer compared to natural broadleaved canopies. In the studied plantations pine regeneration
was confined to few scattered seedlings and regeneration groups. Based on these findings silvicultural concepts for the further
management of black pine plantations in the Middle Balkan Range are discussed. 相似文献
39.
Buck BC Ulrich R Kuiper H Reinacher M Peters M Heimberg P Holsteg M Puff C Haas L Ganter M Distl O 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(7-8):329-336
Profiles of blood cell counts were evaluated for 15 calves from three different farms. These calves showed petechia in the mucous membranes and in the skin and prolonged secondary bleeding after puncture. The clinical course of the disease could be observed in eleven calves. With exception of one case, the blood cell counts indicated a severe anaemia, leukocytopenia and thrombocytopenia. Out of these 15 calves, six calves survived and the other nine calves died or had to be euthanized due to the severity of the disease. Necropsy of these nine calves revealed petechia in the skin, subcutis, muscles, in inner organs and all serous membranes. Pathohistological examination showed a depletion of the bone marrow and lymphatic tissue in eight calves. These findings confirmed the diagnosis of bovine neonatal pancytopenia (BNP) for eight of these nine calves. Bluetongue virus serotype 8 was tested negatively using PCR. Bovine virus diarrhoea virus (BVDV) was negatively tested using immunofluorescence and cell culture and salmonella species were negatively tested in seven dissected calves. A cluster of toxins was negatively tested in one of the dissected calves. All 15 calves had high antibody titres for BVDV. The BVDV-antibody titres from twelve dams with affected calves were positive in six cases and not detectable in the other six cases. In three of the six dams with not detectable BVDV-antibody titres, calves were fed with colostrum of a further dam with high BVDV-antibody titres. In the further three dams without detectable BVDV-antibody titres, we could not ascertain which colostrum has been fed to the calves. BVDV-specific antigen could not be detected in any of the samples from the calves and dams tested. Using the activity of the gamma-glutamyl-transferase, we assumed a sufficient supply with colostrum for the examined calves.The cause for the occurrence of these BNP cases was due to bone marrow depletion.The reason for the bone marrow depletion remained unclear. However, it was obvious that the BNP described here is highly likely caused by colostrum from cows with positive BVDV-antibody titres. 相似文献
40.
Manfred Kerschberger Günther Franke Werner Schuricht 《Archives of Agronomy and Soil Science》2013,59(1-2):147-164
Die Gehalte für die sechs Schwermetalle Cd, Cr, Cu, Ni, Pb und Zn in landwirtschaftlich relevanten Stoffgruppen (mineralische und organische Düngestoffe, Kulturpflanzen und tierische Produkte) wurden aus Literaturdaten für die beiden statistischen Maßzahlen Mittelwert und Spannweite der Mittelwerte in Übersichtstabellen zusammengefasst. 相似文献