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Sakamoto K Yano T Kobayashi T Hagino A Aso H Obara Y 《Domestic animal endocrinology》2007,32(4):260-272
Growth hormone (GH) plays a specific role to inhibit apoptosis in the bovine mammary gland through the insulin-like growth factor (IGF)-I system, however, the mechanism of GH action is poorly understood. In this study, we show that GH dramatically inhibits the expression of IGFBP-5, and GH along with IGF-I enhanced the phosphorylation of Akt through the reduction of IGF binding protein (IGFBP)-5. To determine how GH affects Akt through IGF-I in bovine mammary epithelial cells (BMECs), we examined the phosphorylation of Akt in GH treated BMECs and found that IGF-I induced phosphorylation of Akt was significantly enhanced by the treatment with GH. We demonstrated that GH reduces mRNA and protein expression of IGFBP-5 in BMECs, but it does not affect the expression of IGFBP-3. To determine that the enhanced effect of the Akt phosphorylation by the treatment of GH is due to the inhibition of the expression of IGFBP-5, we examined the effect of IGFBP-3 and -5 on the phosphorylation of Akt through IGF-I in the GH-treated BMECs. The phosphorylation of Akt was inhibited in a dose-dependent manner when IGFBP-5 was added at varying concentrations and was also inhibited in the presence of IGFBP-3. The results of this study suggest that GH plays an important role on mammary gland involution in bovine mammary epithelial cells. 相似文献
4.
RN Zadoks E Scholz SM Rowe JM Norris HB Pooley J House 《Australian veterinary journal》2023,101(4):142-152
Numerous culture-based diagnostics are available on the Australian and international markets for on-farm detection of bacterial pathogens in milk. Use of such diagnostics may provide an opportunity to improve the prudent use of antimicrobials in udder health management. Farms are low-resource settings in terms of diagnostic microbiology capacity. The World Health Organisation has identified criteria for the evaluation of diagnostic tests in low resource settings based on Accuracy, Sensitivity, Specificity, User-friendliness, being Rapid or Robust, Equipment-free and being Deliverable (ASSURED). Here, we review how those criteria can be interpreted in the context of microbiological diagnosis of mastitis pathogens, and how on-farm diagnostics that are currently available in Australia perform relative to ASSURED criteria. This evaluation identifies multiple trade-offs, both with regard to scientific criteria and with regards to convenience criteria. More importantly, the purpose of testing may differ between farms, and test performance should be evaluated relative to its intended use. The ability of on-farm mastitis diagnostics to inform mastitis treatment decision-making in a timely and cost-effective manner depends not just on test characteristics but also on farm-specific pathogen prevalence, and on the farm enterprise's priorities and the farm manager's potential courses of action. With most assay evaluations to date conducted in professional laboratories, there is a surprising dearth of information on how well any of the diagnostic tests perform on-farm and, indeed, of the on-farm decision-making processes that they aim to inform. 相似文献
5.
We investigated the turnover time of microbial biomass-C in Japanese upland soils with various textures and examined the soil physicochemical properties influencing their turnover time. Samples from five different soil types (sand-dune regosol, light-colored Andosol, humic Andosol, brown forest soil, and dark red soil) were taken from upland concrete-frame plots in the experimental field of Chiba University. Each soil amended with [U -13C] glucose was incubated for 80 d at 25°C. Microbial biomass-C and -13C in soil were periodically determined by the fumigation-extraction method. The longest turnover time of microbial biomass-C was observed in the dark red soil (215 d) followed by the humic Andosol (134 d), brown forest soil (97 d), and light-colored Andosol (83 d) and the shortest in the sand-dune regosol (45 d). The turnover time of microbial biomass-C was significantly correlated with the value of soil clay (R: 0.917*), CEC (R: 0.921*), and macroaggregate (R: 0.907*) contents, but not with the total-C content. The amount of microbial biomass-C showed a close correlation with the turnover time of microbial biomass-C, suggesting that the turnover time of microbial biomass-C is an important factor influencing the accumulation of microbial biomass-C in soil. 相似文献
6.
Konomi Sakamoto Wataru Honto Masaharu Iguchi Nobuhiro Ogawa Kazuhiro Ura Yasuaki Takagi 《Fisheries Science》2009,75(1):91-98
This study examines the following in the Japanese mitten crab: (1) the structure of the exoskeleton with special reference
to its calcification; (2) the progression of post-molt cuticle formation and calcification. In the crab, the structure and
calcification state of the exoskeleton at the molt and during the inter-molt stage were similar to those of other crustaceans.
During the inter-molt, the exoskeleton consisted of four cuticle layers; the outermost epicuticle, the exocuticle, the endocuticle
and the innermost membrane layer. Intense calcification was observed in the exo- and endocuticle. At the molt, the synthesis
of the epi- and exocuticle was already complete, and the addition of the endocuticle began after the molt. Calcification of
the exocuticle initiated soon after the molt, but there was a delay between endocuticle matrix synthesis and calcification.
Histology showed that the process of calcification was similar to that in other crustaceans. However, calcium concentrations
within the exoskeleton continued to increase and never reached the levels of the inter-molt stage at the end of the experiment.
This suggests that the Japanese mitten crab is relatively slow to calcify compared to other crustaceans. 相似文献
7.
PJ Waller G Bernes SM Thamsborg A Sukura SH Richter K Ingebrigtsen J H?glund 《Acta veterinaria Scandinavica》2001,42(1):31-44
Preparations derived from plants were the original therapeutic interventions used by man to control diseases (including parasites), both within humans and livestock. Development of herbal products depended upon local botanical flora with the result that different remedies tended to develop in different parts of the world. Nevertheless, in some instances, the same or related plants were used over wide geographic regions, which also was the result of communication and/or the importation of plant material of high repute. Thus, the Nordic countries have an ancient, rich and diverse history of plant derived anthelmintic medications for human and animal use. Although some of the more commonly used herbal de-wormers were derived from imported plants, or their products, many are from endemic plants or those that thrive in the Scandinavian environment. With the advent of the modern chemotherapeutic era, and the discovery, development and marketing of a seemingly unlimited variety of highly efficacious, safe synthetic chemicals with very wide spectra of activities, herbal remedies virtually disappeared from the consciousness--at least in the Western world. This attitude is now rapidly changing. There is a widespread resurgence in natural product medication, driven by major threats posed by multi-resistant pest, or disease, organisms and the diminishing public perceptions that synthetic chemicals are the panacea to health and disease control. This review attempts to provide a comprehensive account of the depth of historical Nordic information available on herbal de-wormers, with emphasis on livestock and to provide some insights on potentially rewarding areas of "re-discovery" and scientific evaluation in this field. 相似文献
8.
Sakamoto K Lewbart GA Smith TM 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2001,30(2):50-52
Abstract: Blood samples were collected from 29 juvenile red pacu ( Piaractus brachypomus ), ornamental freshwater fish, to establish baseline blood chemistry values. Mean (minimum-maximum) values, obtained by automated bichromatic analysis and ion selective electrode analysis, were as follows: sodium, 150.4 (146–159) mmol/L; potassium, 3.93 (2.7–5.0) mmol/L; chloride, 138.7 (128–150) mmol/L; total CO2 , 7.5 (6–10) mmol/L; albumin, 0.86 (0.5–1.0) g/dL; lactate dehydrogenase, 237.8 (65–692) IU/L; aspartate aminotransferase, 49.1 (0–125) IU/L; creatinine, 0.31 (0.2–0.4) mg/dL; calcium, 10.80 (9.5–12.5) mg/dL; anion gap, 6.89 (1.2–12.5) mmol/L; and phosphorus, 7.29 (4.1–8.9) mg/dL. 相似文献
9.
SM Rhind 《Reproduction in domestic animals》2005,40(4):282-290
Contents The sources and characteristics of endocrine disrupting compounds (EDCs) are reviewed and discussed with respect to their potential effects on farm animal health, welfare and productivity. The importance of certain properties of these compounds in relation to the expression of their biological effects is addressed together with potential routes of exposure. It is concluded that little is known of factors affecting the tissue concentrations of EDCs in farm animals, the concentrations that are required to perturb physiological function in these species, the effects of prolonged exposure to low doses, the effect of cocktails of EDCs and other pollutants or the responses of specific organs and physiological systems that are affected by EDCs. Much of the available information pertaining to EDCs is derived from epidemiological studies of wildlife species and from laboratory animal studies and while these studies have significant limitations, they are considered to be valuable indicators of potential effects in farm animal species. The results of such studies, together with the small amounts of data from studies of ruminants, indicate that there may be significant effects of exposure to environmental levels of EDCs on farm animal health, even although effects are not generally apparent in practice, at this time. 相似文献
10.
Ishikawa A Sakamoto H Katagiri S Takahashi Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(1):99-102
The longitudinal changes in fecal steroid hormone concentrations and sexual behavior in 2 mated/pregnant and 3 non-mated female Hokkaido brown bears were investigated during the breeding season. Behavioral estrus (standing) lasted for 14 and 32 days in the mated females and for 25 to 36 days in the non-mated females. In non-mated females, sexual behavior, such as female-female mounting and masturbation, was observed for several days before and after the estrous period. In mated females, mean fecal estradiol-17beta concentrations were higher in the estrous period than in the post-estrous period, while fecal progesterone concentrations were higher in the post-estrous period than in the estrous period. The similar trends of steroid hormone changes were observed in the non-mated females. 相似文献