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81.
Participatory approaches in agroforestry combine land, labor, and knowledge, by blending local experience with external expert support for sloping land restoration. We describe and analyze over a decade of bottom-up agroforestry development processes that today are influencing national policies. In the 1990s, after economic upheaval following the collapse of trade with the USSR (Soviet Union) rapid conversion of sloping lands to agriculture, in association with heavy rainfall events, caused widespread erosion and landslides. In response, pilot scale ??user groups?? obtained rights-to-use, rights-to-harvest and rights-to-plan or access to sloping lands for tree products and food. All three rights were novel in the DPR Korea and jointly contributed to success, together with active research support. Innovations in double-cropping annual food crops together with non-competitive contour strips of valuable fruits (aronia berry: Aronia melanocarpa) and/or high-value timber (larch: Larix leptolepis) emerged as preferred local agroforestry systems. Broad support for agroforestry practices has now emerged within the Ministry of Land and Environmental Protection as well as a number of universities and research centres. Further development will require increased engagement with agricultural and horticultural agencies, while the social dimensions of participatory agroforestry continue to provide rich learning.  相似文献   
82.
Oliet  Juan A.  Artero  Francisco  Cuadros  Simón  Puértolas  Jaime  Luna  Lourdes  Grau  Jose M. 《New Forests》2012,43(5-6):925-939
New Forests - Increasing plant size has been considered a way to improve survival and growth of planted containerized stock under dry conditions. Additionally, deep planting provides advantages to...  相似文献   
83.
The aim of this study was to determine the prevalence and risk factors associated with infection due to Neospora caninum in serum samples from 488 sheep originating from 63 farms in 63 municipalities distributed across eight of the twelve mesoregions of the state Minas Gerais, southeastern Brazil. For detection of N. caninum the sheep serum samples were subjected to the indirect fluorescence antibody test (IFAT ≥ 50). To identify the risk factors associated with infection due to N. caninum a questionnaire was filled out for each herd by interviewing, the individual responsible for the herd, demanding information on the general characteristics of the property. Sixty-four sheep sera (13.1%; 95% CI=10.3-16.4) presented IgG-specific anti-N. caninum antibodies with the following titers: 50 (49; 76.6%), 100 (7; 10.9%), 200 (4; 6.2%), 400 (3; 4.7%) and 800 (1; 1.6%). The prevalence of infected sheep per mesoregion ranged from 0 to 28.1%. Out of the 63 farms sampled, 31 (49.2%; 95% CI=36.4-62.1) presented at least one seropositive sheep. No significant association was found between the presence of anti-N. caninum antibodies and the risk factors evaluated on the farms, except for the mesoregion variable (p=0.004; OR=0.429; CI95%=0.182-1.008). These results indicate that there is a need for additional research to define the epidemiological importance of this parasite as a cause of reproductive problems in sheep herds in Minas Gerais.  相似文献   
84.
85.
The ultrastructure of the spermatozoa of the domestic duck (Anas platyrhynchos sp.) was analysed by transmission and scanning electron microscopies and compared with the results obtained in preliminary studies involving other non-passerine birds. The spermatozoa were characterised by the presence of a short head, short midpiece and long principal piece. The head consisted of a reduced acrosome that contained moderately electron-dense homogenous material. The implantation fossa was observed between the base of the nucleus and the proximal centriole. The midpiece contained electron-dense material associated with the proximal centriole and nuclear membrane, and a long distal centriole surrounded throughout its length by 11-12 elliptical mitochondria. A dense annulus separating the midpiece from the principal piece was visible. Posterior to the annulus, the axoneme was formed surrounded by a dense fibrous sheath, representing the principal piece or flagellum, which was a long segment with a smooth surface and a smaller diameter than the midpiece. The spermatozoon of the domestic duck resembles that of other non-passerine birds, corresponding to a basic type of spermatozoon similar to that of reptiles, called sauropsid type.  相似文献   
86.
Hematological and coagulation profiles were studied in crossbred dogs experimentally infected with Angiostrongylus vasorum. Two groups of five dogs were experimentally inoculated with 50 and 100 third stage infective larvae (L(3)) of A. vasorum per kilogram of body weight. A third group of five uninfected animals was used as control. One sample of 10 ml of blood was collected from each animal on the 10, 20, 30, and 45 days after inoculation (dai) and at 30-day intervals thereafter for the remainder of the 210-day experimental period. The blood sample was used for the complete hemogram and platelet count, as well as measurements of prothrombin time, partial thromboplastin time and factors V and VIII. Anemia was observed in infected dogs, 6 weeks after the infection. The eosinophils presented peaks in four periods after infection. Thrombocytopenia became accentuated on the 72 dai. Decreased prothrombin time activity and increased partial thromboplastin time were observed at the 6 and 9 weeks after infection and decreased of factors VIII and V activities occurred from 4 to 6 weeks after infection. It may be conclude that infection by A. vasorum in dogs may cause a discrete anemia during the acute phase which is probably regenerative. In addition, important hemostatic alterations due to the infection suggest a chronic intravascular consumption coagulopathy.  相似文献   
87.
Melamine-urea-formaldehyde resin production has increased in the last years due to low formaldehyde emissions and improved moisture resistance when applied on wood-based panels. Melamine is a relatively high-cost raw material in the resin formulation and has a significant effect on wood-based panel properties. It is important for industry to implement efficient quality control methods to determine melamine content in resins. The main objective of this work was to develop chemometric techniques for off-line monitoring of melamine content using near-infrared spectroscopy. The use of interval partial least squares regression allowed identifying the most interesting spectral ranges for analysis (4,400–4,800 and 5,200–5,600 cm?1) and the best preprocessing methods to use in the determination of this property. When the appropriate spectral range and preprocessing methods are selected, it is possible to obtain calibration models with high correlation coefficients.  相似文献   
88.
The objectives of this study were to evaluate the dry matter intake (DMI), digestibility, average daily gain (ADG), microbial efficiency, empty body weight (EBW) gain, and body composition of Nellore bulls. Additionally, Nellore bull maturity was estimated, and the prediction equation for DMI, suggested by the Brazilian nutrient requirements system (BR CORTE; Azevêdo et al. 2010), was evaluated. Thirty-three Nellore bulls, with a mean initial weight of 259?±?25 kg and age of 14?±?1 months, were used in this study. Five animals were slaughtered at the beginning of the experiment (control group), and the remaining 28 were divided into 4 groups, each slaughtered at 42-day intervals. Their diet was composed of corn silage and concentrate (55:45). The power model was used to estimate muscle tissue, bone tissue, crude protein (CP), mineral matter (MM), and water present in the empty body, while the exponential model was used to estimate adipose tissue and ether extract (EE) present in the empty body. When expressed in kilograms per day, differences were observed (P?<?0.05) only for the intake of EE and neutral detergent fiber as a function of feedlot time periods. Although there was a difference in relation to nutrient intake, it did not affect (P?>?0.05) digestibility, with the exception of EE digestibility. The equation suggested by BR CORTE correctly estimates the DMI of Nellore bulls. ADG was not affected (P?>?0.05) by time spent in the feedlot. No differences were observed (P?>?0.05) for microbial efficiency; a mean value of 142 g microbial crude protein/kg total digestible nutrients was achieved. The muscle and bone tissues, CP, MM, and water present in the empty body increased as the animal grew, although at a lower rate. The adipose tissue and EE present in the empty body increased their deposition rate when the animal reached its mature weight. Maturity is defined as when an animal reaches 22 % EE in the empty body, which corresponds to 456 kg of EBW in Nellore bulls. Therefore, this study can conclude that the feedlot time period does not affect DMI, nutrient intake, ADG, or microbial efficiency. The equation proposed by BR CORTE (Azevêdo et al. 2010) correctly estimates the DMI of Nellore bulls, which reach maturity when an EBW of 456 kg is attained.  相似文献   
89.
90.
The n-butanol fraction (BF) obtained from the crude extract of the marine sponge Petromica citrina, the halistanol-enriched fraction (TSH fraction), and the isolated compounds halistanol sulfate (1) and halistanol sulfate C (2), were evaluated for their inhibitory effects on the replication of the Herpes Simplex Virus type 1 (HSV-1, KOS strain) by the viral plaque number reduction assay. The TSH fraction was the most effective against HSV-1 replication (SI = 15.33), whereas compounds 1 (SI = 2.46) and 2 (SI = 1.95) were less active. The most active fraction and these compounds were also assayed to determine the viral multiplication step(s) upon which they act as well as their potential synergistic effects. The anti-HSV-1 activity detected was mediated by the inhibition of virus attachment and by the penetration into Vero cells, the virucidal effect on virus particles, and by the impairment in levels of ICP27 and gD proteins of HSV-1. In summary, these results suggest that the anti-HSV-1 activity of TSH fraction detected is possibly related to the synergic effects of compounds 1 and 2.  相似文献   
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