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81.
Two questionnaires were undertaken to obtain improved knowledge of the signalment, incidence and risk factors of the condition termed 'kangaroo gait' (KG; a forelimb locomotor disorder of adult female sheep). The first survey was mailed to 221 veterinary surgeons in practices in northern Britain which provided veterinary care for sheep, and the second was mailed to 438 sheep-flock owners and managers located in the Scottish Borders, who were recruited via their veterinary surgeons. Responses of 84.7 and 30.7% were achieved, respectively. In total, 29.7% of veterinary practices and 24.1% of flock owners and managers had identified one or more cases of KG in their practice area or flocks since the first case was reported in 1976. Almost all respondents indicated that adult females were affected-usually during lactation (and less commonly during late gestation). KG was more common among commercial crossbreeds and less common among sheep grazing hill pasture (than sheep grazing upland or lowland pasture). Cases usually occurred between March and June while sheep were at grass, although it was unclear whether the temporal pattern was associated with grazing or lambing patterns. Stocking densities were significantly higher among affected flocks than among non-affected flocks. The annual number of individuals and flocks identified as being affected had increased since the condition first was identified. Most cases of locomotor disorders resembling KG were not reported to veterinary surgeons. 相似文献
82.
Standfast NF Bock RE Wiecek MM deVos AJ Jorgensen WK Kingston TG 《Veterinary parasitology》2003,115(3):213-222
Demand for live trivalent tick fever vaccine containing Babesia bovis, Babesia bigemina and Anaplasma centrale produced by the Department of Primary Industries, Queensland, has increased from less than 10,000 doses in 1988 to 500,000 doses in 2001. This paper describes a series of trials aimed at overcoming certain constraints to obtain B. bigemina parasitised erythrocytes (PEs) on a large enough scale from infected splenectomised calves to meet the demand. Passage through a series of splenectomised calves failed to increase the yield per calf but we showed that the dose rate of infected cells could be reduced from the long-time standard of 1x10(7) to 2.5x10(6) without affecting immunogenicity and still leaving a safety margin of at least 50-fold for infectivity. This change quadrupled the potential yield of doses per calf and allowed the DPI to meet the increased demand for B bigemina in vaccine. Due to the high cost and limited availability of suitable, health tested donors, calves previously infected with B. bovis or A. centrale were used to provide B. bigemina organisms but the practice resulted in red cell agglutination in some batches of prepared vaccine. A trial is described where B. bigemina-infected red cells were washed by centrifugation to remove agglutinating antibodies. Washing had no effect on parasite viability and this method is now in routine use in the production of trivalent vaccine. 相似文献
83.
84.
Jubb TF Fordyce G Bolam MJ Hadden DJ Cooper NJ Whyte TR Fitzpatrick LA Hill F D'Occhio MJ 《Australian veterinary journal》2003,81(1-2):66-70
OBJECTIVE: To compare the Willis dropped ovary technique with traditional spaying methods in extensive beef cattle herds in northern Australia. PROCEDURE: Three field trials were conducted simultaneously at different sites in northern Australia in 1996-97. Brahman and Brahman-Shorthorn cross heifers (n = 219, 2 years, 250 to 378 kg) and cows (n = 211, 3 to 16 years, 256 to 540 kg) were allocated by stratified randomisation to three treatments: spaying using the Willis dropped ovary technique (WDOT); spaying using traditional paralumbar and vaginal methods; and unspayed. Following these procedures, these nonpregnant, nonlactating cattle were then exposed to bulls (4 per 100 females) under extensive rangeland conditions for 12 months during which time weight, body condition, pregnancy and ovarian function were monitored and compared. RESULTS: Pregnancy rates varied from 60 to 90% for entire heifers and 80 to 100% for entire cows depending on site. The traditional spay methods were 100% successful in preventing pregnancy; the WDOT was 92 to 97% effective, depending on operator experience. The number of deaths was the same or higher in Willis spayed animals than other groups. Weight changes were similar in all groups at the three sites over the trial period. The time taken to spay using the WDOT was similar to or less than that required for the traditional methods. Uterine abnormalities were not observed in animals spayed with the WDOT, there were however 30 (12.4%) animals where excision of the ovary was incomplete; the still-attached ovarian remnant presumably accounting for the three pregnant animals in this group. CONCLUSION: The WDOT suffers from requiring a high degree of skill in transrectal ovarian manipulation. There were more deaths and more pregnancies than with traditional spay methods. More experienced operators can be expected to achieve lower mortalities, better contraception and higher processing rates. Pregnancy will occur as a consequence of ovarian remnants unless care is taken to ensure removal of the entire ovary. 相似文献
85.
86.
Prevalence of subclinical mastitis and associated risk factors in smallholder dairy cows in Tanzania 总被引:3,自引:0,他引:3
Karimuribo ED Fitzpatrick JL Swai ES Bell C Bryant MJ Ogden NH Kambarage DM French NP 《The Veterinary record》2008,163(1):16-21
A cross-sectional study was carried out on 200 randomly selected farms in each of the Iringa and Tanga regions of Tanzania to estimate the prevalence and risk factors for subclinical mastitis in dairy cows kept by smallholders. Subclinical mastitis was assessed using the California mastitis test (cmt), and by the bacteriological culture of 1500 milk samples collected from 434 clinically normal cows. The percentages of the cows (and quarters) with subclinical mastitis were 75.9 per cent (46.2 per cent) when assessed by the cmt and 43.8 per cent (24.3 per cent) when assessed by culture. Factors significantly associated with an increased risk of a cmt-positive quarter were Boran breed (odds radio [or]=3.51), a brought-in cow (rather than homebred) (or=2.39), peak milk yield, and age. The stripping method of hand milking was associated with a significantly lower prevalence of cmt-positive quarters (or=0.51). The cmt-positive cows were more likely to be culture positive (or=4.51), as were brought-in (or=2.10) and older cows. 相似文献
87.
Kyle W. Shertzer Erik H. Williams Joseph Kevin Craig Eric E. Fitzpatrick Nikolai Klibansky Katie I. Siegfried 《Fisheries Management and Ecology》2019,26(6):621-629
Recreational fishing is increasingly recognised as an important source of mortality for marine fish populations. In the United States, estimates of marine recreational catch and effort were recently revised for the time period 1981 and beyond, and for many species, the revised estimates were substantially higher than the original values. Here, the proportion of total landings that came from the recreational sector in the Southeast US Atlantic was quantified. The proportions for 22 oceanic species and for all species combined were computed, using a full time series of landings (1981–2016) and a more recent time series (1999–2016). For the full and recent time series, landings of most species (15/22 and 17/22, respectively) were dominated by the recreational sector. For all species combined, 71% of landings in the full time series were from the recreational sector, and 76% in the recent time series. Trend analysis indicated that most species had a stable or increasing proportion of landings from the recreational sector. In addition, stock assessments were conducted on four species, and the catch revisions increased the estimated scale of abundance and, in some cases, affected stock or fishery status. This work underscores the importance of recreational fishing for marine resource management. 相似文献
88.
Noel M. Lacerna II Cydee Marie V. Ramones Jose Miguel D. Robes Myra Ruth D. Picart Jortan O. Tun Bailey W. Miller Margo G. Haygood Eric W. Schmidt Lilibeth A. Salvador-Reyes Gisela P. Concepcion 《Marine drugs》2020,18(12)
The bioactivity-guided purification of the culture broth of the shipworm endosymbiont Teredinibacter turnerae strain 991H.S.0a.06 yielded a new fatty acid, turneroic acid (1), and two previously described oxylipins (2–3). Turneroic acid (1) is an 18-carbon fatty acid decorated by a hydroxy group and an epoxide ring. Compounds 1–3 inhibited bacterial biofilm formation in Staphylococcus epidermidis, while only 3 showed antimicrobial activity against planktonic S. epidermidis. Comparison of the bioactivity of 1–3 with structurally related compounds indicated the importance of the epoxide moiety for selective and potent biofilm inhibition. 相似文献
89.
R. L. Botham P. Cairns R. M. Faulks G. Livesey V. J. Morris T. R. Noel S. G. Ring 《Cereal Chemistry》1997,74(1):29-33
Physicochemical techniques, monosaccharide, and linkage analysis, have been used to investigate the digestibility of different forms of cooked barley starch in an ileostomist model. An ileostomate volunteer consumed a flapjack-type biscuit containing either barley flake, flour, or starch. Both starch and mucin were identified in the effluent and were found to make a significant contribution to the potentially fermentable substrate available to the large intestine. Chemical analysis of the effluents showed that the content of resistant starch in the effluent varied with presence and form of nonstarch polysaccharide and after consumption of barley flake and flour was 10.1 and 5.9% of the starch ingested, respectively. Wide-angle X-ray diffraction showed the excreted starch to be A-type only, indicating that the starch consumed in all three flapjack types was ungelatinized. These data demonstrate the potential of physicochemical techniques in the analysis of physiological samples. 相似文献
90.
Juvenile Australian freshwater crayfish ( Cherax tenuimanus ) were individually housed in an experimental battery system and fed HFX CRD 84 and BML 81 S, two proposed standard reference diets for studies of crustacean nutrition. The HFX CRD 84 diet was accepted more readily than the BML 81 S diet. After 100 days, mean weight gain of marron fed the HFX CRD 84 diet was significantly greater than that of those fed the BML 81 S diet. Growth rate, measured 118 percent weight pin per ecdysis, declined during three successive 50 day periods. Growth on the proposed reference diets ranged from 16 to 33% of that achieved with pond raised marron of similar age. Both diets may be useful in the development of species specific modifications relative to nutrient composition. 相似文献