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991.
The complex and rapid-paced development of international trade, coupled with increasing societal demands for the production not only of abundant and inexpensive food, but also of food that is safe and has been raised in a humane and environmentally friendly manner, demands immediate attention from the veterinary community. The new culture of global trade agreements, spurred by the development of the WTO, dictates massive changes and increasing integration of public and private sectors. This is a huge growth area for our profession and will require individuals with a skill set we do not yet provide in our educational framework. In North America, veterinary education is parochial and focused on specialization. This strong orientation toward companion animals fails to provide adequate training for those interested in acquiring the necessary skills for the emerging area of globalization and trade. In South America, curricula are less harmonized with one another and there is tremendous variation in degree programs, rendering it difficult to ascertain whether veterinarians are prepared to assume decision-making responsibilities regarding international transport of food. If we do not begin to prepare our graduates adequately for this emerging market demand, the positions will be filled by other professions. These other professions lack broad-based scientific knowledge about animal physiology and disease causation. Decisions made without adequate background could have devastating consequences for society, including incursions of unwelcome diseases, food safety problems, and public health issues. To prepare our new veterinary graduates for the future and this emerging market, it is important to nurture a global mindset within our academic communities and to promote communications, languages, and an interdependent team mentality. Areas of technical expertise that need a place, perhaps a parallel track, in the curriculum include production medicine, public health, food safety, and international veterinary medicine. The major trade corridors of the future regarding animal-based protein flow between North and South America. It is absolutely essential that we find areas of consensus and deficiencies so that we can harmonize our trade agreements and ensure adequate flow of safe food products from one continent to the other. 相似文献
992.
1. Two experiments were conducted to evaluate the use of date fibre as a partial replacement of maize as a source of energy for growing broiler chicken. In experiment 1, date fibre was given alone to determine apparent metabolisable energy (AME) and apparent ileal digestibility of amino acids and crude fibre. 2. Date fibre had lower AME content (8.7 vs 13.6 MJ/kg) and apparent ileal digestibility coefficients for dry matter (0.35 vs 0.83), crude fibre (0.20 vs 0.54) and amino acids. 3. Based on the results of experiment 1, a growth study was conducted to test the effect of exogenous enzymes on the nutritive value of date fibre (experiment 2). 4. Three date fibre contents (5, 10 and 15%) with and without enzyme supplementation were evaluated. Daily feed intake, body weight gain and feed conversion ratio were measured. At the end of experiment 2, 160 birds were randomly selected and slaughtered to evaluate carcase and meat quality traits as well as measuring ileal viscosity. 5. Substitution of maize by 10 and 15% date fibre significantly depressed AME. Enzyme supplementation did not improve crude fibre digestibility. The inclusion of date fibre in the diets except at 5% decreased average daily gains, feed intake and feed conversion ratio. 6. Addition of date fibre caused a significant increase in the weights of total digestive tract, pancreas and caecum. Addition of date fibre or the exogenous enzyme had no significant effect on carcase or meat quality characteristics. 7. Date fibre increased ileal digesta viscosity compared to the control. Addition of the exogenous enzyme decreased the viscosity of the basal diets but had no effect on the date fibre diets.8. This study indicated that date fibre can be included at levels of 5% in broiler diets without affecting performance. 相似文献
993.
Eysker M Bakker N van der Hall YA van Hecke I Kooyman FN van der Linden D Schrama C Ploeger HW 《Veterinary parasitology》2006,141(1-2):91-100
Two experiments were performed in 2002 and 2003 to evaluate the effect of biological control of gastrointestinal nematodes in sheep through the daily feeding of 500,000 chlamydospores of Duddingtonia flagrans/kg bodyweight to lactating ewes during the first 9 weeks with their young lambs on pasture. In both experiments four groups of eight ewes and their April-borne lambs were used. They were turned out on four separate plots (plots A) at the beginning of May, moved to similar separate plots after 3 (plots B) and 6 weeks (plots C), respectively, and weaning occurred after 9 weeks. In both experiments, two groups were fed spores daily while the two other groups served as controls. The effect of D. flagrans application was evaluated through faecal egg counts of ewes and lambs, the yield of faecal cultures in ewes, pasture larval counts and worm counts of lambs and tracer lambs. The results demonstrated no effect of D. flagrans application during the first 5 (2002) or 4 (2003) weeks. Subsequently, fungus application strongly reduced the yield in faecal cultures of the ewes. This was, however, not reflected in the pasture larval counts, but lower worm burdens were observed in tracer lambs of 'treated' plots C in 2002 than on those of 'control' plots. In 2003 worm burdens in 'treated' lambs returned to plots B were lower than those of 'control' lambs and a tendency for the same was observed for plots C. However, in all groups, lambs and tracer lambs developed severe haemonchosis. 相似文献
994.
An experiment was conducted to evaluate a novel procedure for estimating endogenous losses of P and for measuring the apparent total tract digestibility (ATTD) and true total tract digestibility (TTTD) of P in 5 inorganic P sources fed to growing pigs. The P sources were dicalcium phosphate (DCP), monocalcium phosphate (MCP) with 50% purity (MCP50), MCP with 70% purity (MCP70), MCP with 100% purity (MCP100), and monosodium phosphate (MSP). A gelatin-based, P-free basal diet was formulated and used to estimate endogenous losses of P. Five P-containing diets were formulated by adding 0.20% total P from each of the inorganic P sources to the basal diet. A seventh diet was formulated by adding 0.16% P from MCP70 to the basal diet. All diets were fed to 7 growing pigs in a 7 x 7 Latin square design, and urine and feces were collected during 5 d of each period. The endogenous loss of P was estimated as 139 +/- 18 mg/kg of DMI. The ATTD of P in MSP was greater (P < 0.05) than in DCP, MCP50, and MCP70 (91.9 vs. 81.5, 82.6, and 81.7%, respectively). In MSP, the TTTD of P was 98.2%. This value was greater (P < 0.05) than the TTTD of P in DCP, MCP50, and MCP70 (88.4, 89.5, and 88.6%, respectively). The ATTD and the TTTD for MCP70 were similar in diets formulated to contain 0.16 and 0.20% total P. Results from the current experiment demonstrate that a P-free diet may be used to measure endogenous losses of P in pigs. By adding inorganic P sources to this diet, the ATTD of P can be directly measured and the TTTD of P may be calculated for each source of P. 相似文献
995.
Fekete S Szakáll I Kósa E Andrásofszky E Fodor K Hidas A Tözsér J 《Acta veterinaria Hungarica》2001,49(4):385-398
A growth trial was carried out to test the effect of organic, trivalent chromium and L-carnitine on the body composition of growing rats. At the same time, an evaluation of different measurement methods (weight of epididymal fat pad, adipocyte morphometry, total body electrical conductivity) was performed. Outbred Wistar rats of 30 days of age were fed diets of different (0, 10 and 20%) protein level. The diets were supplemented with 4 mg/kg Cr as chromium nicotinate, and 100 mg/kg L-carnitine. The experimental feeding lasted 15 days, after a 5-day-long adjustment period. It was found that Cr addition increased feed intake. Both treatments caused changes in body composition, increasing fat and protein deposition. Organic chromium had no effect at either protein level, while L-carnitine improved the protein retention only at an optimum (20%) protein supply. No statistically significant correlation was found between total body electrical conductivity (TOBEC) and body composition, which could be attributed to the great individual differences. A close correlation was found among total body fat percentage, weight of epididymal fat pad and the adipocyte surface. The data suggest that there is an interaction between dietary protein supply and the effect of repartitioning agents. 相似文献
996.
S. Dänicke I. Halle E. Strobel E. Franke & H. Jeroch 《Journal of animal physiology and animal nutrition》2001,85(9-10):301-313
997.
Adherence to various host cell lines of Mycoplasma bovis strains differing in pathogenic and cultural features 总被引:1,自引:0,他引:1
Thomas A Sachse K Dizier I Grajetzki C Farnir F Mainil JG Linden A 《Veterinary microbiology》2003,91(2-3):101-113
Mycoplasma bovis is known to be responsible for pneumonia and arthritis in calves, as well as mastitis in dairy cows. Despite clear evidence of its pathogenic potential, little is known about mechanisms of cytadherence and the molecular factors involved. The purpose of this work was to compare adherence rates of M. bovis field strains to different host cell lines and study the effects of cloning and sub-culturing M. bovis strains on their adherence properties. Eighteen metabolically labeled M. bovis strains isolated from different pathological backgrounds were examined in adherence trials using four different host cell lines, i.e. embryonic bovine lung (EBL), embryonic bovine trachea (EBTr), Madin Darby bovine kidney (MDBK) and rabbit kidney (RK) cells. Although large interstrain variations in adherence rates (3.4-19.1%) were measured they could not be correlated to the pathological background (pneumonia, arthritis or mastitis). Adherence rates to the fibroblast cell line (EBTr) were significantly lower than those to the three epithelial cell lines (EBL, MDBK and RK). The only non-pathogenic strain (221/89) exhibited lower adherence rates than three isolates from clinical mastitis. Interestingly, adherence rates were significantly reduced after in vitro passaging. In contrast, no effect of single cloning of strains on adherence was observed. There was no general correlation between expression of variable surface proteins (Vsps) as monitored by immunoblotting and adherence rates, although alterations in Vsp expression profiles were seen as a consequence of passaging. As there is probably a large number of adhesins, variable and non-variable, on the surface of M. bovis cells the issue is very complex, and the most active components have yet to be identified. 相似文献
998.
999.
Radford AD Stockley P Taylor IR Turner R Gaskell CJ Kaney S Humphris G Magrath C 《The Veterinary record》2003,152(14):422-427
A course in communication skills has been developed specifically for veterinary students, based on those delivered at many medical schools, and making extensive use of professional actors as simulated clients. Its aim is to raise awareness of the importance of communication among veterinary undergraduates at all stages of the curriculum, and it allows them to role-play in acted-out scenarios. Facilitated small groups provide an environment in which students can receive feedback on their own performance and also give feedback to their colleagues. An independent evaluation suggests that the opportunity to role-play increased the students' confidence in communicating with others. They were able to identify their personal strengths as communicators and gain insights into the aspects of communication they could improve. Feedback and subsequent discussions were highly valued, with the actors playing a crucial role in providing feedback from the client's perspective. Students were able to use the knowledge they acquired when consulting with real clients. Most of the students suggested that the course should continue in its current format, but with more time provided for it in the curriculum. 相似文献
1000.
Chaves RN Lima-Verde IB Celestino JJ Duarte AB Alves AM Matos MH Campello CC Name KP Báo SN Buratini J Figueiredo JR 《Domestic animal endocrinology》2010,39(4):249-258
The aim of the present study was to investigate the effects of fibroblast growth factor-10 (FGF-10) on the survival, activation (transition from primordial to primary follicles), and growth of goat preantral follicles cultured in vitro. Pieces of ovarian cortex were cultured for 1 and 7 d in the absence or presence of FGF-10 (0, 1, 10, 50, 100, and 200 ng/mL). Noncultured and cultured tissues were processed and analyzed by histology, transmission electron microscopy, and viability testing. Results showed that after 7 d, a greater percentage (79.9%) of morphologically normal follicles (containing an oocyte with regular shape and uniform cytoplasm, and organized layers of granulosa cells without a pyknotic nucleus) was observed when cultured with 50 ng/mL of FGF-10 when compared with other concentrations of FGF-10 (0 ng/mL, 67.3%; 1 ng/mL, 68.2%; 10 ng/mL, 63.3%; 100 ng/mL, 64.4%; 200 ng/mL, 52.7%). Ultrastructural analyses and viability testing using fluorescent markers confirmed the follicular integrity of FGF-10 (50 ng/mL)-treated fragments after 7 d of culture. After 7 d, all FGF-10 concentrations reduced the percentage of primordial follicles and increased the percentage of developing follicles. In the presence of 50 ng/mL of FGF-10, follicles increased in diameter after 7 d of culture when compared with other concentrations tested. In conclusion, this study demonstrates that FGF-10 maintains the morphological integrity of goat preantral follicles and stimulates the growth of activated follicles in culture. The culture conditions identified here contribute to the understanding of the factors involved in goat early follicular development. 相似文献