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991.
Needles of the Ponderosa pine (Pinus ponderosa) induce premature parturition in cattle when ingested during late pregnancy, especially during the third trimester. The closer to term, the more likely that pine needles will induce parturition. Experiments were designed to describe the clinical signs and behavior associated with ingestion of pine needles. Pine needles adversely affected only pregnant cows and did not seem to affect nonpregnant, cycling cows, sheep, goats, or rabbits. Premature parturition was more likely if cows ingested the needles after the 8th mo of pregnancy, if they ingested pine needles over a period of 3 d or more, and if cows ate a relatively large amount of pine needles (about 2.2 to 2.7 kg/d). A synthetic progesterone, melangesterol acetate, and a prostaglandin inhibitor (ketoprofen) seemed to be of some prophylactic benefit; however, further research is required to assess the practicality of the approach and the magnitude of the benefit. Ponderosa pine bark and new-growth branch tips, which seem to be more potent inducers of premature parturition, may be useful in the extraction and identification of the parturifacient component(s).  相似文献   
992.
Inclusion of high-ionic strength buffers helped us to develop a sandwich ELISA to detect hemorrhagic septicemia virus (HSV) in cell culture and infected trout tissue extracts. For maximal sensitivity of 0.1 to 0.2 ng/well/100 microliters or about 10 to 50 TCID50/well/100 microliters, trout extracts were diluted 1:1 and assayed for the earliest synthesized nucleoprotein N. Simultaneous binding of the N protein from HSV in the sample to the wells coated with monoclonal antibody (2D5 against the N protein) and to the peroxidase-labeled monoclonal antibody (2C9 against the N protein) proceeded during a 2-hour incubation at 20 to 22 C (room temperature). The response was linear between 6 to 60 ng/well of purified virus. Monoclonal antibodies used were noncompetitive with each other and reacted with F1, F2, 23.75, and 5 Spanish isolates of HSV, but not with infectious hematopoietic necrosis or infectious pancreatic necrosis viruses. Tissue specimens with low content of HSV virus may now be assayed directly without use of cell culture, rapidly, and with high precision, during the acute phase of the disease in salmonid fishes.  相似文献   
993.
Physiologically based statements on the effectivity of lysine, methionine/cystine and threonine of protein sources as well as on the requirement of these amino acids depending on performance were derived on the basis of a total of 568 N balance measurings at growing female fattening pigs in the live weight range between 30 and 50 kg (Liebert, 1986) with the application of the N utilization model by Gebhardt (1963) as well as of particular further developments by the linking of N utilization and the utilization of the respective limiting amino acid. By means of combining protein sources with known amino acid effectivity, the additivity principle for content values of effective amino acid in the feed protein (c.k) suggested as criteria was verified. On the whole, it could thus be proved that the suggested method can decisively contribute to the elaboration of a closed system of quality assessment and requirement assessment depending on performance as well as of supply covering requirements of growing pigs. The advantages in particular over the 'slope ratio' method are emphasized.  相似文献   
994.
Poxvirus in farmed Nile crocodiles   总被引:1,自引:0,他引:1  
In an outbreak of wart-like skin lesions in nine-month-old farmed Nile crocodiles (Crocodylus niloticus) the lesions were especially common on the head and neck but occurred on all parts of the body except the tail. Eosinophilic intracytoplasmic inclusion bodies were present in epithelial cells and further examination of the lesions by transmission electron microscopy revealed the presence of a poxvirus. An autogenous vaccine was produced from material from the lesions and in six vaccinated crocodiles the lesions healed more quickly than in unvaccinated controls.  相似文献   
995.
A dog with chronic dirofilariasis (Dirofilaria immitis) was given 15 doses of 12 or 24 mg of levamisole/kg of body weight in 6 treatments within 96 days. Concentration of microfilariae in the blood was determined before and after treatment, and Aedes triseriatus mosquitoes were fed on the dog 1 to 5 days after each treatment and examined for D immitis larvae. Several adult worms were recovered from the dog 160 days after the end of the treatments.  相似文献   
996.
The genetic relationship among individuals at one locus is characterized by nine coefficients of identity. The coefficients of inbreeding, coancestry and dominance (or fraternity) are just linear functions of them. Here, it is shown how they can be estimated using biallelic and triallelic markers using the method of moments, and comparisons are made with other methods based on molecular coancestry or molecular covariance. It is concluded that in the general case of dominance and inbreeding with biallelic markers, only the coefficients of inbreeding and coancestry can be estimated, but neither the single coefficients of identity nor the coefficient of dominance can be estimated. More than two alleles are required for a full estimation as illustrated with the triallelic situation.  相似文献   
997.
Follistatin (FST) acts as a positive regulator of muscle development by inhibiting the activities and expression of myostatin. The recombinant duck FST protein was injected into hatching eggs and was also added to the medium of duck myoblast to study its role on duck embryonic muscle development and gene expressions. Duck embryo weight increased 3.49% (p > 0.05) in FST treatment group as compared with control group, but minor effects were found on leg or breast muscle weights of ducklings at 2 days post‐hatching (p > 0.05). Relative expression of Pax7 was upregulated in both leg and breast muscle tissues (p < 0.05), while MyoD was only upregulated in leg muscle (p < 0.05), and Myf5 was only upregulated in breast muscle (p < 0.05). Relative expression of myostatin was downregulated in both muscle tissues researched (p < 0.05). In vitro studies also showed some maker genes relevant to protein synthesis and degradation, cells’ proliferation and differentiation had significant changes in myoblasts after treated with FST. These results suggested that in ovo feeding of recombinant FST protein to duck hatching eggs had an effect on duck embryo development but have less roles on the duck embryonic muscle development.  相似文献   
998.
999.
1000.
RFamide‐related peptide‐3 (RFRP‐3), the mammalian ortholog of gonadotropin‐inhibiting hormone, has been implicated as a mediator between reproduction and energy balance. This study aimed to investigate the physiological effects of RFRP‐3 on the process of ovarian development in food‐restricted pre‐pubertal ewes. The results showed that food restriction significantly inhibited the ovarian development and follicular growth. The data of qPCR in the hypothalamic–pituitary–ovarian (HPO) axis showed that food restriction not only upregulated RFRP‐3 mRNA expression but also downregulated the mRNA expression of gonadotropin‐releasing‐hormone receptor, follicle‐stimulating hormone receptor and luteinizing hormone receptor (LHR). Immunohistochemistry of RFRP‐3 in the ovaries suggested that RFRP‐3 may regulate the follicular development. These results suggested that the changes of RFRP‐3 in response to food restriction might influence the HPO axis and inhibit ovarian development.  相似文献   
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