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291.
Sanderson WT Madsen MD Rautiainen R Kelly KM Zwerling C Taylor CD Reynolds SJ Stromquist AM Burmeister LF Merchant JA 《Journal of agricultural safety and health》2006,12(1):71-81
Agriculture remains one of the most hazardous industries in the U.S., with tractor overturns producing the greatest number of agricultural machinery-related fatalities. Rollover protective structures (ROPS) and seatbelts effectively reduce tractor overturn deaths. However, a large proportion of tractors in use in American agriculture are older tractors without ROPS and seatbelts. This article describes the tractor-related responses from participants in a population-based study conducted in Keokuk County, Iowa. This study was designed to measure rural and agricultural adverse health and injury outcomes and their respective risk factors. Questionnaires were partially developed from well-documented national surveys. Questions about agricultural machinery use, presence of safety equipment on the machinery, work practices, and attitudes about farm safety were included. Study participants on farms who owned tractors had an average of 3.1 tractors with an average age of 27 years. Only 39% of the 665 tractors had ROPS. Tractor age was associated with the presence of ROPS; 84% of tractors manufactured after 1984 were ROPS-equipped, whereas only 3% of tractors manufactured before 1960 were ROPS-equipped. ROPS-equipped tractors were significantly more common on larger farms and households with higher income. Only 4% of the farmers reported that their tractors had seatbelts and they wore them when operating their tractors. The results of this study support the findings of other studies, which indicate that many older tractors without ROPS and seatbelts remain in use in American agriculture. Until a dramatic reduction in the number of tractors in the U.S. operated without ROPS and seatbelts is achieved, the annual incidence of 120 to 130 deaths associated with tractor overturns will persist. 相似文献
292.
Between April 1999 and March 2004, metabolic profile analyses were performed on individual blood samples from 35,506 dairy cattle in the UK. Assessment of the cows' energy status by the analysis of plasma samples for beta-hydroxybutyrate, glucose and non-esterified fatty acids showed that 70.4 per cent of the cows in early lactation (10 to 20 days calved), 57.1 per cent of the cows in mid-lactation (51 to 120 days calved) and 57.7 per cent of the dry cows within 10 days of their predicted calving date had one or more energy metabolites outside the optimum range; in addition, 16 per cent of the cows in early lactation, 5.6 per cent of those in mid-lactation and 20.5 per cent of the dry cows within 10 days of their predicted calving date had a low plasma urea nitrogen concentration, indicating poor intakes of effective rumen-degradable protein. Abnormalities in the concentrations of magnesium, inorganic phosphate, copper, selenium and iodine were relatively uncommon. The transitional period, particularly in late pregnancy, was commonly identified as a constraint on productivity. Nutritional problems were most commonly associated with poor feed intakes and poor feed management, rather than with the formulation of the rations. 相似文献
293.
The objective of this study was to evaluate the effects of in utero and postnatal exposure of a high‐protein (HP; n = 9) or moderate‐protein (MP; n = 16) diet on growth, and serum metabolite, ghrelin and leptin concentrations during the first 4 months of life in kittens. It was hypothesized that blood indices would be modified due to diet. Blood samples were collected from kittens at 4, 8, 12 and 16 weeks of age. Kittens were weaned at 8 weeks of age onto the same diet as the dam. Body weight was measured weekly from birth and daily food intake for each litter was recorded post‐weaning. Serum concentrations of urea nitrogen, total protein and triglycerides were greater (P < 0.05) in kittens fed the HP diet. Serum cholesterol concentrations were greater (P < 0.05) in MP‐fed kittens at 4 weeks of age. Moderate‐protein fed kittens tended to have greater (P < 0.10) serum ghrelin concentrations. Leptin concentrations were not affected by diet, but changed over time (P < 0.05). Our data indicate that diet and age of kittens affect circulating concentrations of peptides important in appetite regulation. Further research testing the effects of in utero and early postnatal nutrient exposure on feline obesity risk in adulthood is needed. 相似文献
294.
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296.
Kelly P O'Sullivan K Berry D More S Meaney W O'Callaghan E O'Brien B 《Irish veterinary journal》2009,62(1):36-42
Research has shown that total bacterial count (TBC), which is the bacterial growth per ml of milk over a fixed period of time, can be decreased by good hygiene and farm management practices. The objective of the current study was to quantify the associations between herd management factors and bulk tank TBC in Irish spring calving, grass-based dairy herds. The relationship between bulk tank TBC and farm management and infrastructure was examined using data from 400 randomly selected Irish dairy farms where the basal diet was grazed grass. Herd management factors associated with bulk tank TBC were identified using linear models with herd annual total bacterial score (i.e., arithmetic mean of the natural logarithm of bulk tank TBC) included as the dependent variable. All herd management factors were individually analysed in a separate regression model, that included an adjustment for geographical location of the farm. A multiple stepwise regression model was subsequently developed. Median bulk tank TBC for the sample herds was 18,483 cells/ml ranging from 10,441 to 130,458 cells/ml. Results from the multivariate analysis indicated that the following management practices were associated with low TBC; use of heated water in the milking parlour; participation in a milk recording scheme; and tail clipping of cows at a frequency greater than once per year. Increased level of hygiene of the parlour and cubicles were also associated with lower TBC. Herd management factors associated with bulk tank TBC in Irish grazing herds were generally in agreement with most previous studies from confinement systems of milk production. 相似文献
297.
J Li K Villemoes Y Zhang Y Du PM Kragh S Purup Q Xue AM Pedersen AL Jørgensen JE Jakobsen L Bolund H Yang G Vajta 《Reproduction in domestic animals》2009,44(1):122-127
The purpose of our work was to establish an efficient-oriented enucleation method to produce transgenic embryos with handmade cloning (HMC). After 41–42 h oocytes maturation, the oocytes were further cultured with or without 0.4 μg/ml demecolcine for 45 min [chemically assisted handmade enucleation (CAHE) group vs polar body (PB) oriented handmade enucleation (OHE) group respectively]. After removal of the cumulus cells and partial digestion of the zona pellucida, oocytes with visible extrusion cones and/or polar bodies attached to the surface were subjected to oriented bisection. Putative cytoplasts without extrusion cones or PB were selected as recipients. Two cytoplasts were electrofused with one transgenic fibroblasts expressing green fluorescent protein (GFP), while non-transgenic fibroblasts were used as controls. Reconstructed embryos were cultured in Well of Wells (WOWs) with porcine zygote medium 3 (PZM-3) after activation. Cleavage and blastocyst rates were registered on day 2 and day 7 of in vitro culture respectively. Meanwhile, the total blastocyst cell number was counted on day 7. We found that the difference was only observed between blastocyst rates (38.6 ± 2% vs 48.1 ± 3%) of cloned embryos with GFP transgenic fibroblast cells after CAHE vs OHE. With adjusted time-lapse for zonae-free cloned embryos cultured in WOWs with PZM-3, it was obvious that in vitro developmental competence after CAHE was compromised when compared with the OHE method. OHE enucleation method seems to be a potential superior alternative method used for somatic cell nuclear transfer (SCNT) with transgenic fibroblast cells. 相似文献
298.
Stacey R. Byers Julie A. Cary Kelly D. Farnsworth 《The Canadian veterinary journal. La revue veterinaire canadienne》2009,50(7):745-749
This study evaluated a retrograde orotracheal intubation technique and compared
it to the traditional normograde intubation technique used in llamas. Oral
anatomical features, which can impair visualization of the epiglottis and
laryngeal structures, and the production of excessive salivary secretions make
it difficult to establish an airway under emergency conditions. Normograde
intubation involves placing a stylet through the mouth into the trachea and
advancing the endotracheal tube over the stylet into the trachea. For retrograde
intubation, a nested trochar with cannula is placed into the cervical trachea
and a stylet is advanced through the cannula and out the mouth. The endotracheal
tube is advanced over the stylet back into the trachea. Our evaluation of both
techniques found no statistical difference in time to place the stylet or
endotracheal tube; however, fewer attempts were needed to place the tube using
the retrograde technique. We found the retrograde technique to be a viable
option for intubating llamas. 相似文献
299.
Lori Lavigne-Brunette Marc-Andr Joly Susan Kelly Chantal J. Frgeau Rmy A. Aubin 《Research in veterinary science》2009,87(2):245-248
Cynomolgus macaques (also known as longtail or crab-eating macaques) Macaca fascicularis, are an important non-human primate model for biomedical research. Using a case study involving a suspected occurrence of twin birth, we demonstrate that the highly polymorphic human variable-number tandem repeat (VNTR) mini-satellite probes D1S7, D2S44, D3S42 and D4S184 can be successfully employed as a rapid screening strategy to complement husbandry records in order to establish genetic relatedness in a captive colony. 相似文献
300.