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91.
Breton C Claux D Metton I Skorski G Bervillé A 《Journal of agricultural and food chemistry》2004,52(3):531-537
Virgin olive oil is made from diverse cultivars either mixed or single. Those ensure different tastes and typicity, and these may be also enhanced by the region of production of cultivars. The different olive oil labels correspond to their chemical composition and acidity. Labels also may correspond to a protected origin indication, and thus, such oils contain a given composition in cultivars. To verify the main cultivars used at the source of an olive oil sample, our method is based on DNA technology. DNA is present in all olive oil samples and even in refined oil, but the quantity may depend on the oil processing technology and oil conservation conditions. Thus, several supports were used to retain DNA checking different techniques (silica extraction, hydroxyapatite, magnetic beads, and spun column) to prepare DNA from variable amounts of oil. At this stage, it was usable for amplification through PCR technology and especially with the magnetic beads, and further purification processes were checked. Finally, the final method used magnetic beads. DNA is released from beads in a buffer. Once purified, we showed that it did not contain compounds inhibiting PCR amplification using SSR primers. Aliquot dilution fractions of this solution were successfully routinely used through PCR with different SSR primer sets. This enables confident detection of eventual alien alleles in oil samples. First applied to virgin oil samples of known composition, either single cultivars or mixtures of them, the method was verified working on commercial virgin oil samples using bottles bought in supermarkets. Last, we defined a protocol starting from 2 x 40 mL virgin olive oil, and DNA was prepared routinely in about 5 h. It was convenient to genotype together several loci per sample to check whether alleles were in accordance with those of expected cultivars. Thus, forensic applications of our method are expected. However, the method needs further improvement to work on all oil samples. 相似文献
92.
F. van Knapen J.H. Franchimont E.J. Ruitenberg P. André B. Baldelli T.E. Gibson C. Gottal S.A. Henriksen G. Kohler O. Ronéus N. Skovgaard C. Soulé K.L. Strickland S.M. Taylor 《Veterinary parasitology》1981,9(2):117-123
Four methods employed in the diagnosis of experimental porcine trichinellosis (trichinoscopy, digestion method, immunofluorescence and enzyme linked immunosorbent assay (ELISA)) were compared by eleven laboratories in the countries of the European Economic Community and Sweden. The aim of this study was to test the reliability of ELISA during the onset of T. spiralis infection. Material from conventionally raised pigs infected with 1500 or 10000 larvae was compared to uninfected controls at Day 17 and Day 21 post infection.The serological techniques gave higher percentages of positive results than the direct techniques. Specific antobodies could be demonstrated with ELISA at an earlier stage and at higher percentages than with the other methods. ELISA micro-assay was the most sensitive procedure. 相似文献
93.
André Brassard 《Canadian journal of veterinary research》1965,29(10):253-258
During the period 1945-1962, percentage deaths of anserine birds (ducks, geese and swans) did not vary remarkably from year to year even though the population has more than quadrupled during the same period. The number of deaths with amyloidosis has increased significantly even though the death rate did not change. The number of deaths due to tuberculosis, mould, renal diseases, hepatitis and infection accompanied by amyloidosis also increased, especially during the second half the study period. Cases of known secondary amyloidosis accounted for 71.4% whereas 28.6% of the remaining cases were classified as ”doubtfully” primary. Sites of deposition amyloid in the two categories were the same and it has never been observed in the heart. The amyloid deposits in the birds did not differ from those in man when examined by number of histochemical methods. 相似文献
94.
Francoz D Desrochers A Fecteau G Desautels C Latouche JS Fortin M 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(3):336-343
The objective was to develop an experimental model of septic arthritis in calves and to evaluate the effect of treatment on cytologic and bacteriologic variables of synovial fluid. The right tarsus of 7 healthy Holstein bull calves were inoculated with 10(8) colony-forming units of viable Escherichia coli of a pap-positive strain (day 1). On day 2, joint lavage was performed and antibiotic treatment was instituted. Cytologic examinations, bacterial cultures, and pap factor determinations by polymerase chain reaction (PCR) were performed on synovial fluid samples that were collected daily until day 4, then every 4 days until day 24. Results of physical examination, the severity of lameness, and swelling were recorded. Clinical signs of septic arthritis appeared on day 2 and persisted until day 9 for all calves. Bacterial cultures from all calves were positive for E. coli on day 2, and remained positive until day 3 for 1 calf and until day 4 for 5 calves. In addition, PCR results were positive for all calves, with 6 positive through day 3 and 1 positive through day 4, after which a positive result was again obtained on day 24. Synovial fluid neutrophil counts and white blood cell counts were significantly increased on days 2-4; however, synovial total protein concentrations were increased (P < .05) throughout the experiment in comparison to day 1. Results of all bacterial cultures were negative on day 8, although clinicopathologic signs of inflammation persisted until day 20. This model successfully induced acute septic arthritis in calves. Rapid recovery occurred within 1 week when an appropriate treatment was instituted early in the course of the disease. 相似文献
95.
Roy MA Vrins A Beauchamp G Doucet MY 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(5):744-750
This study was performed to determine the prevalence of ulcers in the gastric squamous mucosa in Standardbred racehorses. Observations were performed at monthly intervals between the beginning of their training season and their 1st qualifying race. This study also identified risk factors at different levels of race training. Forty-eight Standardbred racehorses from 3 training stables in Quebec, Canada, were studied. Baseline historical information and gastroscopic findings were recorded at the beginning of the trial, and once a month thereafter, between December 2001 and June 2002, until the horse's 1st qualifying race or the end of the training. Intensity of training ranged from jogging to intensive training just before the 1st race and was assigned an ordinal score. Location of squamous ulcers and their appearance were observed on gastroscopy, and an ordinal score was assigned. Prevalence of squamous ulcers from the 2nd through the 4th month (72-88%) of training remained at a significantly higher level (P = .002 to .04) than at the onset of the study (38%) and was also higher in intensely trained horses than in joggers (93% versus 56%). Moderate or more intensive training increased the odds (odds ratio [OR], 3.39; confidence interval [CI], 1.34-8.56; and OR, 11.4; CI, 3.21-40.5, respectively) of detecting ulcers with higher scores. These odds were also higher in trotters (OR, 2.17; CI, 1.07-4.43) than in pacers and generally increased with the duration of training. Duration of training, training level, and gait type also influenced the number of sites with ulcers in the same way. Ulcers had higher scores along the lesser curvature (LC) and the margo plicatus (MP) areas of the stomach. It was concluded that squamous ulcers appeared early in the training of Standardbred racehorses, that the number of sites affected and the ulcer score are related to the intensity of training, and that trotters are more prone to squamous ulcers than pacers. 相似文献
96.
Diagnostic tests for small ruminant lentiviruses 总被引:1,自引:0,他引:1
de Andrés D Klein D Watt NJ Berriatua E Torsteinsdottir S Blacklaws BA Harkiss GD 《Veterinary microbiology》2005,107(1-2):49-62
Maedi visna virus and caprine arthritis encephalitis virus are closely related retroviruses that cause chronic inflammatory disease in small ruminants. The infections are characterised by insidious onset and slow progression. Diagnosis of infection is usually by serological testing. A variety of assays are available for this purpose, though the relative sensitivity and specificity of these assays has not been compared systematically. Here we review recent developments in laboratory diagnostic methods and their use in field diagnosis. The results suggest that a combination of ELISA and PCR might afford optimal detection of SRLV infection. 相似文献
97.
Spatial association between forest heterogeneity and breeding territory boundaries of two forest songbirds 总被引:1,自引:1,他引:0
Human activities and natural disturbances create spatial heterogeneity within forested landscapes, leading to both sharp and gradual boundaries in vegetation and abiotic attributes, such as rocks. Those boundaries may affect the detailed delineation of avian territories (independently of their general location), but their role is largely unknown. We tested, using a spatial analysis approach, whether spatial heterogeneity of vegetation and abiotic attributes were associated with territory boundaries of ten black-throated blue warblers (Dendroica caerulescens) and 14 ovenbirds (Seiurus aurocapillus). The study was conducted during summer 1999 in a mature deciduous forest near Québec City, Canada. Singing males were mapped from repeated surveys at 756 points, 25 m apart, on a 49 ha grid. Spatial heterogeneity was obtained from 27 attributes measured at each point. Boundaries of bird territories, vegetation, and abiotic attributes were delineated using the lattice-wombling boundary detection algorithm. The spatial association between territory and microhabitat boundaries was computed using the spatial overlap statistics. There was significant spatial overlap between territory boundaries and those of 15 and 17 attributes for black-throated blue warbler and ovenbird, respectively. The attributes most strongly associated with territory boundaries were conifer seedling cover, grass and total vegetation cover between 0-2 m high for black-throated blue warbler and fern cover, vegetation-covered rocks and shrub diversity for ovenbird. Complementary to this, a redundancy analysis (RDA) was used to compare attributes associated with the general occurrence of males to those whose boundaries were associated specifically with territory boundaries. Most attributes whose boundaries were associated with territory boundaries did not correspond to resource attributes, i.e., those where birds were detected most frequently. We conclude that soft boundaries associated with spatial heterogeneity may help shape forest bird territories by providing landmarks not necessarily related to resources used within territories. 相似文献
98.
99.
De Champlain AF 《Journal of veterinary medical education》2004,31(1):61-65
Determining whether or not an examinee has met an adequate standard of performance constitutes a central task for licensure and certification bodies. Consequently, standard setting is a key activity for all certification and licensing testing programs. The purpose of this article is to provide an overview of methods that have been proposed for set a passing standard on an examination. First, the distinction between norm-referenced and criterion-referenced methods for setting a standard will be outlined. Then, both test-centered and examinee-centered methods for setting a passing standard will be explicated. The importance of factoring in the consequences of adopting a standard will also be illustrated via the Hofstee method. In the concluding section, important issues pertaining to the selection of panelists as well as the validation of the standard will be addressed briefly. 相似文献
100.
Inhibitory and excitatory neurotransmitters in the cerebrospinal fluid of epileptic dogs 总被引:3,自引:0,他引:3
Ellenberger C Mevissen M Doherr M Scholtysik G Jaggy A 《American journal of veterinary research》2004,65(8):1108-1113
OBJECTIVE: To determine concentrations of excitatory and inhibitory amino acids in CSF of a large number of dogs with idiopathic epilepsy or genetic epilepsy and to evaluate changes in CSF amino acid concentration with regard to drug treatment and sex. ANIMALS: 35 Labrador Retrievers with genetic epilepsy (20 male and 15 female), 94 non-Labrador Retrievers with idiopathic epilepsy (71 male and 23 female), and 20 control dogs (10 male and 10 female). PROCEDURE: Collection of CSF was performed > 72 hours after the occurrence of seizures. Cerebrospinal fluid concentrations of gamma-aminobutyric acid (GABA), glutamate (GLU), aspartate (ASP), serine, and glycine were determined by use of high performance liquid chromatography with electrochemical detection. RESULTS: CSF concentrations of GABA and GLU were significantly lower in Labrador Retrievers with genetic epilepsy (LR-group dogs) than in control-group dogs or in non-Labrador Retrievers with idiopathic epilepsy (non-LR-group dogs). The GLU-to-GABA ratio was significantly higher in LR-group dogs than in non-LR-group dogs. CSF concentrations of GLU and ASP were significantly lower when all dogs with epilepsy (non-LR- and LR-group dogs combined) were compared with control-group dogs. CONCLUSIONS AND CLINICAL RELEVANCE: A decrease in CSF concentrations of GABA appears to play a role in the pathogenesis of genetically determined epilepsy in Labrador Retrievers. However, this decrease in CSF concentrations of GABA may also be a consequence of seizure activity. The GLU-to-GABA ratio may prove to be a useful indicator of genetic epilepsy in Labrador Retrievers. 相似文献