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101.
Molecular typing of Mycobacterium bovis isolates from south-east Brazil by spoligotyping and RFLP 总被引:2,自引:0,他引:2
Zanini MS Moreira EC Salas CE Lopes MT Barouni AS Roxo E Telles MA Zumarraga MJ 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2005,52(3):129-133
The identification of 163 strains of Mycobacterium bovis by polymerase chain reaction (PCR) and microbiological tests was carried out on 252 tuberculous-like lesions (TLLs) collected from slaughtered cattle in south-east Brazil. This study compared the usefulness of three genotyping techniques, IS6110-restriction fragment length polymorphism (RFLP), polymorphic guanine-cytosine-rich sequence (PGRS)-RFLP and direct repeat (DR)-spoligotyping, as applied to M. bovis isolates. Based on IS6110-RFLP genotyping we selected a group of 23 isolates containing more than one IS6110 copy, along with 16 samples containing one IS6110 copy from different geographical areas, evenly distributed among dairy (eight) and beef cattle (eight). These selected isolates were analysed by PGRS-RFLP and DR-spoligotyping genotyping. Dairy cattle (17%) display a higher frequency of multiple IS6110 copies than beef cattle (10%). A comparison between the genotype data obtained fails to show a correlation between the main clusters found by the three techniques. However, the clustering of each genotyping procedure revealed that the majority of strains are closely related. The RFLP-PGRS patterns showed a sizable group (20.5%) containing a 5.5 kb fragment and the predominant spoligotype is similar to that from the BCG vaccine strain. Unexpectedly, four strains (2.4%) showed drug resistance to 0.2 microg/ml isoniazid and 20 microg/ml ethionamide, but none of them was resistant to rifampicin or other antibiotics tested. 相似文献
102.
Eichhornia crassipes (water hyacinth), a major aquatic weed in India, is one of the targets in a biological weed control research programme in India. A fungal pathogen, Alternaria alternata, is being evaluated as a biological control agent for this weed. The feasibility of solid substrate for the mass production of A. alternata has been examined. Conidia production and virulence of A. alternata were affected by temperature, light and incubation period. The highest number of conidia were produced on rice seed followed by wheat, sorghum, maize seeds and cornmeal at 20°C when exposed to near‐ultraviolet than on the other substrates, while the least conidia were observed on these substrates under light conditions. At 20°C, large numbers of virulent conidia were produced on rice seeds after 4 weeks of incubation under constant dark conditions. Henceforth, the use of rice seeds as a solid substrate for production of A. alternata could be a feasible method to produce conidia in a village co‐operative scenario in India. 相似文献
103.
M. S. Zanini E. C. Moreira C. E. Salas M. T. P. Lopes A. S. Barouni E. Roxo M. A. Telles M. J. Zumarraga 《Zoonoses and public health》2005,52(3):129-133
The identification of 163 strains of Mycobacterium bovis by polymerase chain reaction (PCR) and microbiological tests was carried out on 252 tuberculous‐like lesions (TLLs) collected from slaughtered cattle in south‐east Brazil. This study compared the usefulness of three genotyping techniques, IS6110‐restriction fragment length polymorphism (RFLP), polymorphic guanine‐cytosine‐rich sequence (PGRS)‐RFLP and direct repeat (DR)‐spoligotyping, as applied to M. bovis isolates. Based on IS6110‐RFLP genotyping we selected a group of 23 isolates containing more than one IS6110 copy, along with 16 samples containing one IS6110 copy from different geographical areas, evenly distributed among dairy (eight) and beef cattle (eight). These selected isolates were analysed by PGRS‐RFLP and DR‐spoligotyping genotyping. Dairy cattle (17%) display a higher frequency of multiple IS6110 copies than beef cattle (10%). A comparison between the genotype data obtained fails to show a correlation between the main clusters found by the three techniques. However, the clustering of each genotyping procedure revealed that the majority of strains are closely related. The RFLP‐PGRS patterns showed a sizable group (20.5%) containing a 5.5 kb fragment and the predominant spoligotype is similar to that from the BCG vaccine strain. Unexpectedly, four strains (2.4%) showed drug resistance to 0.2 μg/ml isoniazid and 20 μg/ml ethionamide, but none of them was resistant to rifampicin or other antibiotics tested. 相似文献
104.
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106.
Barros Lílian Moreira Prochnow Daiane de Oliveira Victoria Freitas da Silva Airton Rosa de Oliveira Antonio Costa da Maia Luciano Carlos 《Journal of Crop Science and Biotechnology》2019,22(1):31-36
Journal of Crop Science and Biotechnology - The morphological characterization allows one to estimate and evaluate the genetic distance among different varieties, identifying heterotrophic groups... 相似文献
107.
R. M. Honji A. M. Narcizo M. I. Borella E. Romagosa R. G. Moreira 《Fish physiology and biochemistry》2009,35(1):109-123
Fecundity and oocyte development in Salminus hilarii female brood stock were analyzed with the aim of investigating the impact of migration impediment on oogenesis. Histological
analyses of the ovaries were performed in adult females caught in two different environments—the Tietê River (natural) and
captivity—and the gonadossomatic index, oocyte diameter and fecundity determined. Five germ cell development stages (oogonium,
perinucleolar, cortical alveoli, vitellogenic, ripe) and two other structures (postovulatory follicles and atretic oocytes)
were observed in females caught in the river. Captive animals lacked the ripe oocytes and postovulatory follicles and had
a relatively higher number of atretic oocytes. Females in captivity are known to produce larger oocytes, and they release
fewer eggs in each spawn (absolute fecundity) when compared with animals that are able to migrate. Our results suggest that
the Tietê River is undergoing alterations which are being reflected in the reproductive performance of S. hilarii, mainly due to the presence of atretic oocytes in females caught in the river. The lack of postovulatory follicles and ripe
oocytes in captive animals reveals that migratory impediment negatively impacts final oocyte maturation. However, the stage
of maturation reached is adequate for ovulation induction with hormone manipulation. 相似文献
108.
Ana R. Linde Jorge I. Izquierdo Josino Costa Moreira Eva Garcia‐Vazquez 《水产资源保护:海洋与淡水生态系统》2008,18(6):891-895
- 1. Invasions are a main concern for conservationists. Identification of causes that raise or promote an invader's success is one of the first steps for preventing and/or fighting against invasions.
- 2. In the Brazilian River Paraiba do Sul, juveniles of invasive tilapia Oreochromis niloticus were detected associated with degraded habitats (mainly pollution from various sources). The relative abundance of juveniles of the competitor native species pearl cichlid Geophagus brasiliensis, morphologically and ecologically very similar, was negatively associated with habitat degradation.
- 3. A species‐specific molecular marker was employed to permit unambiguous identification of these small juveniles (2–3 cm long), which represent the most vulnerable life stage of both species.
- 4. It is suggested that adaptation to degraded habitats is one of the characteristics of invasive species, and consequently habitat conservation and restoration may help to prevent fish invasions.
109.
110.
Modelling the impact of agricultural abandonment and wildfires on vertebrate diversity in Mediterranean Europe 总被引:1,自引:0,他引:1
Agricultural land abandonment, widespread in the Mediterranean, is leading to a recovery of scrubland and forests which are
replacing open habitats and increasing wildfire events. Using published data, we modelled the global and regional impact of
abandonment and wildfires on 554 species of terrestrial vertebrates occurring in Mediterranean Europe. For all groups except
amphibians, open habitats or farmland sustained higher species richness. Open habitats showed regional differences in their
conservation value, western areas being particularly important for birds and amphibians and eastern areas for reptiles. Scrublands
hosted fewer species than open habitats, farmland and forest, but sustained several endemic birds and mammals. The greater
species richness of forests was mostly due to species widespread in Europe. Wildfires promote scrubland expansion in detriment
of forest; because more species are associated to eastern forests, fire is predicted to affect more seriously this region.
Scrubland conservation value was found to be highest in the west, where fire might have a positive impact. Fire regime, however,
plays a crucial role. Although large fires have a negative impact, small-scale fires may favour biodiversity in abandoned
areas. Due to the intrinsic difficulty in managing abandoned land to preserve the original Mediterranean vertebrate diversity,
the best option to achieve this goal is the development of policies designed to make farmers and traditional farmland survive. 相似文献