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531.
Moyà-Solà S Köhler M Alba DM Casanovas-Vilar I Galindo J 《Science (New York, N.Y.)》2004,306(5700):1339-1344
We describe a partial skeleton with facial cranium of Pierolapithecus catalaunicus gen. et sp. nov., a new Middle Miocene (12.5 to 13 million years ago) ape from Barranc de Can Vila 1 (Barcelona, Spain). It is the first known individual of this age that combines well-preserved cranial, dental, and postcranial material. The thorax, lumbar region, and wrist provide evidence of modern ape-like orthograde body design, and the facial morphology includes the basic derived great ape features. The new skeleton reveals that early great apes retained primitive monkeylike characters associated with a derived body structure that permits upright postures of the trunk. Pierolapithecus, hence, does not fit the theoretical model that predicts that all characters shared by extant great apes were present in their last common ancestor, but instead points to a large amount of homoplasy in ape evolution. The overall pattern suggests that Pierolapithecus is probably close to the last common ancestor of great apes and humans. 相似文献
532.
Oró J Updegrove WS Gibert J McReynolds J Gil-Av E Ibanez J Zlatkis A Flory DA Levy RL Wolf C 《Science (New York, N.Y.)》1970,167(3918):765-767
Organogenic elements, mainly carbon, nitrogen, phosphorus, and sulfur are present in the particulate material and in a breccia rock from Tranquillity Base in amounts ranging from 5 to 4200 parts per million. The major compounds of carbon released by heating are carbon monoxide and carbon dioxide; the former predominates. Small amounts of other compounds of carbon have also been observed. Sulfur can be released as hydrogen sulfide by treatment with acid. The carbon isotopic delta(13L)C values are definitely nonterrestrial (+ 13 to + 18.5 per mil). 相似文献
533.
Dopico-García MS López-Vilariñó JM Gonzalez-Rodríguez MV 《Journal of agricultural and food chemistry》2007,55(8):3225-3231
Antioxidants commonly used in polyolefins were studied in commercial food packages made of low- and high-density polyethylene (LDPE and HDPE), polypropylene (PP), polyvinylchloride (PVC), and polyethylene terephtalate (PET) and in a LDPE film extruded at the laboratory. The phenolic antioxidants BHA, BHT, AO 2246, AO 425, Ethanox 330, Irganox 1010, and Irganox 1076 were studied together with the phosphite Irgafos 168 and their two degradation products, phosphate and DBP. Antioxidants were extracted from polyolefins using microwave energy and analyzed using high-performance liquid chromatography (HPLC) to determine the antioxidant content in the diverse commercial films. Irganox 1010 and Irganox 1076 were found in the majority of the samples generally together with the phosphite Irgafos 168 and its oxidized product (phosphate). Specific migration levels of each antioxidant were determined by HPLC after pretreatment with solid-phase extraction (SPE) in aqueous food simulants and after their dilution with tetrahydrofuran (THF) in fatty food simulant. These levels were much lower than limits allowed by legislation. 相似文献
534.
Corro M Rubio I Castillo E Galindo L Aluja A Galina CS Murcia C 《Preventive veterinary medicine》1999,38(2-3):101-117
Research was conducted on typical smallholder farms with dual-purpose cattle (DPC) (Bos indicus x B. taurus) in the coastal north-central area of Veracruz, Mexico. The study was divided into two phases. The aim of the first phase was to investigate the effect of blood metabolities, body condition and pasture management on milk yield and postpartum intervals, in order to investigate if the former are suitable indicators of the reproductive and nutritional status of DPC. One hundred and sixty-five calvings of crossbred cows were recorded from January 1992 to November 1994 on 12 small farms. Milk samples were collected twice a week for progesterone analysis. Blood samples and BCS were taken once a month. However, in Phase II emphasis was placed on the effect of pasture management upon reproductive and productive performance of DPC. Records of four farms were obtained from June 1995 to November 1996. Stocking rates were 0.40, 0.87, 0.35 and 1.5 cows/ha for farms A, B, C and D, respectively. Farms A and C used a slow rotation while B and D used a rapid rotation. In Phase I, the changes in BCS during the last month of pregnancy and first month postpartum did not correlate (p > 0.05) with milk yield or reproductive performance. Blood the metabolite profiles were not consistently related to productive or reproductive variables. The effect of farm and season was significant (p < 0.05) on most of the response variables and low productivity on overstocked farms lead to the conclusion that the low reproductive performance of DPC was linked to poor pasture management. During Phase II, farms A (FA) and D (FD) produce more milk than the others. Days to first service, days open, and calving interval were similar for farms B (FB) and C (FC), highest for Farm A, and lowest for Farm D. The forage availability mean was above the critical range of 6-8 kg of dry matter per 100 kg of liveweight (kg DM/100 kg LW) in all farms (range from 6.1 +/- 5.0 to 21.1 +/- 11.2 kg DM/100 kg LW). Farm D had the highest stocking rate (1.5 cows/ha), a rapid rotation (10 paddocks), a good forage availability (7.1 +/- 3.9 kg DM/100 kg LW) with a good quality for a tropical pasture (11.6 +/- 2.4% crude protein), and an economic energy supplementation. These results suggest this type of management could be more widely employed to improve the productivity of DPC on smallholder farms in the Mexican tropics. 相似文献
535.
Gullón B Garrote G Alonso JL Parajó JC 《Journal of agricultural and food chemistry》2007,55(14):5580-5587
The potential of apple pomace for lactic acid production by simultaneous saccharification and fermentation (SSF) was evaluated. The effects of the cellulase to solid ratio (CSR), the liquor to solid ratio (LSR), and the beta-glucosidase to cellulase ratio (BCR) on the kinetics of lactic acid generation were assessed, and a set of mathematical models was developed to reproduce and predict the lactic acid concentration of fermentation broths. Operating at low cellulase and cellobiase charges (1 FPU/g and 0.25 IU/FPU, respectively) and short reaction times (10 h), SSF media containing 27.8 g of lactic acid/L were obtained with a volumetric productivity of 2.78 g/Lh. Material balances showed that the SSF processing of 100 kg of dry apple pomace results in the production of 36.6 kg of lactic acid, 18.3 kg of oligomeric carbohydrates (which can be used as ingredients for functional foods), 8.4 kg of microbial biomass, and 8 kg uronic acids. 相似文献
536.
Luis E. C. Conceição Cláudia Aragão Nadège Richard Sofia Engrola Paulo Gavaia Sara Mira Jorge Dias 《Fish physiology and biochemistry》2010,36(1):1-16
Major gaps in knowledge on fish larval nutritional requirements still remain. Small larval size, and difficulties in acceptance
of inert microdiets, makes progress slow and cumbersome. This lack of knowledge in fish larval nutritional requirements is
one of the causes of high mortalities and quality problems commonly observed in marine larviculture. In recent years, several
novel methodologies have contributed to significant progress in fish larval nutrition. Others are emerging and are likely
to bring further insight into larval nutritional physiology and requirements. This paper reviews a range of new tools and
some examples of their present use, as well as potential future applications in the study of fish larvae nutrition. Tube-feeding
and incorporation into Artemia of 14C-amino acids and lipids allowed studying Artemia intake, digestion and absorption and utilisation of these nutrients. Diet selection by fish larvae has been studied with
diets containing different natural stable isotope signatures or diets where different rare metal oxides were added. Mechanistic
modelling has been used as a tool to integrate existing knowledge and reveal gaps, and also to better understand results obtained
in tracer studies. Population genomics may assist in assessing genotype effects on nutritional requirements, by using progeny
testing in fish reared in the same tanks, and also in identifying QTLs for larval stages. Functional genomics and proteomics
enable the study of gene and protein expression under various dietary conditions, and thereby identify the metabolic pathways
which are affected by a given nutrient. Promising results were obtained using the metabolic programming concept in early life
to facilitate utilisation of certain nutrients at later stages. All together, these methodologies have made decisive contributions,
and are expected to do even more in the near future, to build a knowledge basis for development of optimised diets and feeding
regimes for different species of larval fish. 相似文献
537.
Zsigmond Jeney Tímea Rácz Kim D. Thompson Saravanane Poobalane László Ardó Alexandra Adams Galina Jeney 《Fish physiology and biochemistry》2009,35(4):677-682
Males of two strains of carp, wild Duna (D), and inbred Szarvas 22 (22), were selected for high and low stress response. Two
purebreds of D and 22, from randomly chosen parents and four crosses, 22 × 22-L (low stress response), 22 × 22-H (high stress
response), 22 × D-L (low stress response) and 22 × D-H (high stress response) from selected stress response parents were produced
and vaccinated with a commercial Aeromonas salmonicida/Aeromonas hydrophila vaccine and their circulating antibody response evaluated 1, 3, 5, and 7 weeks post-vaccination by ELISA. Significantly higher
titres of circulatory antibodies against A. hydrophila were found in the families 22 and cross 22 × 22-L compared to other groups. The development of circulatory antibodies against
A. hydrophila in all crosses having at least one D parent was low and remained low throughout the experiment. The level of circulatory
antibodies against atypical A. salmonicida in the inbred strain increased following a booster vaccination with the highest values measured in inbred strain 22 and cross
22 × 22 L. The different varieties of carp had different levels of survival against experimental challenge with A. hydrophila. The greatest survival was obtained in strain 22 and cross 22 × 22-L, while ~90% of D wild carp and cross 22 × D (independent
of their stress response) died. Survival results correlated well with the antibody response of the different groups: 22 and
22 × 22-L had the highest antibody titres against A. hydrophila and the greatest level of survival. 相似文献