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Gonzalo A. Chávez Álvaro J. Opazo 《Journal of Veterinary Behavior: Clinical Applications and Research》2012,7(6):386-389
This article presents a clinical case of predatory aggression that represents a problem for public health. The patient was a 2-year-old male German shepherd referred to the behavior clinic at the School of Veterinary Medicine owing to its aggressive behavior toward people and other dogs. The dog tended to form a pack with the other dogs of the household and killed neighborhood dogs, cats, hens, and rabbits. The presumptive diagnosis was “predatory aggression” associated with “territorial and protective aggression.” The risk analysis determined that the dog should be euthanized. Nevertheless, the owner refused, and hence behavior modification and drug therapy were recommended. A year later, the dog killed again (another dog), indicating that despite the drug and behavioral treatment, it is likely that its predatory aggression will never be resolved. 相似文献
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Polizopoulou ZS Kazakos G Georgiadis G Soubasis N Koutinas Ch Koutinas AF 《Journal of Feline Medicine and Surgery》2002,4(4):209-212
In this report two cases of localised tetanus in two young (<1 year) intact male and outdoor DSH cats, which had been missing, are described. Clinical examination revealed severe muscular spasms on the right (case 1) or both thoracic limbs (case 2). In the latter cat, wrinkling of the forehead and mild trismus were also seen. The routine diagnostic workup (CBC, survey radiographs of the spine, CSF analysis) did not reveal any abnormalities in both cats. EMG testing on the affected muscles in the second animal showed persistent spontaneous motor unit potentials, strongly indicating tetanus. The treatment, that was symptomatic (diazepam, metronidazole) and supportive (physical therapy, assist feeding and intravenous fluid therapy) resulted in the progressive improvement of limb rigidity and the restoration of motor dysfunction in a period of 5- (case 1) and 2- (case 2) month duration. 相似文献
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In Tunisia both Psammomys obesus and P. vexillaris are found. These taxa have been the subject of taxonomic controversy for some time, due to variability in the classical morphological characters used for taxonomic recognition. In this study we investigated skull size and shape variation in the genus Psammomys by using geometric morphometrics to evaluate the extent of intra- and interspecific shape variation and explicitly tested for the impact of allometric shape variation on species discrimination. Eleven populations of the two species from 10 localities in Tunisia were studied. Statistical analyses of size and shape showed large size variation within P. obesus, but no shape differences were revealed among populations of this species. Interspecific analysis revealed that P. vexillaris had the smallest skull. Principal component analysis and Procrustes distances showed good discrimination between the two species after removal of the allometric component of shape variation. The results obtained show that allometric-related shape variation could mask discrimination between the two Psammomys species. This finding might explain the uncertainty in classification of these species in the past. The interspecific allometric-free phenotypic differences observed may be associated with adaptive processes linked to the different environmental and trophic preferences of the two species. 相似文献
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Spermatozoa are unique cells because of their morphological and physiological characteristics. They are produced during the process called spermatogenesis. Spermatogenesis consists of three phases: spermatocytogenesis, spermiogenesis and spermiation, during which spermatozoa undergo several changes. Spermatogenesis takes place within the seminiferous tubules containing two types of cells—the germ cells and the Sertoli cells—that alongside the Leydig cells, which play an important role when it comes to normal fertility. Everything is regulated by the hypothalamic–pituitary–gonadal axis and specific hormones due to multi-hormonal feedback systems. Spermatozoa possess morphological and physiological features, which are sometimes completely different from what is observed in various somatic cells. What is more, canine spermatozoa have specific characteristics making them special compared to the spermatozoa of other mammalian species. The metabolic energy production, which is crucial for the appropriate functioning of spermatozoa, can be fuelled by different metabolic pathways utilizing different chemical substrates. Inseparable from the oxidative phosphorylation process is the production of reactive oxygen species, which are both essential and toxic to spermatozoa. Furthermore, epididymis is a very important structure, responsible for the transport and maturation of spermatozoa, which are then stored in the last segment of epididymis—the epididymal cauda. Moreover, the retrieval of spermatozoa from the epididymides is crucial for the development of assisted reproduction techniques and sperm cryopreservation methods. The information gained from the research on domestic dogs might be transferred to their wild relatives, especially those species categorized as endangered. 相似文献
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J. Kittler H. Krüger D. Ulrich B. Zeiger W. Schütze Ch. Böttcher A. Krähmer G. Gudi U. Kästner H. Heuberger F. Marthe 《Genetic Resources and Crop Evolution》2018,65(5):1517-1527
Lemon balm (Melissa officinalis L.) is used since ancient times because of its sedative, spasmolytic and antiviral effects. Its therapeutic impact is due to the content of essential oil and rosmarinic acid. A set of 68 M. officinalis genotypes was evaluated for content and composition of essential oil and the content of rosmarinic acid. For all genotypes the level of ploidy was determined. The 68 genotypes were clone plants grown and evaluated for two years at Quedlinburg. For analysis of secondary metabolites distillation, gas chromatography and high performance liquid chromatography was used. The content of essential oil varied in this study in ranges from 0.03 to 0.33% for the second cut 2010 and 0.01–0.35% for the second cut 2011. The rosmarinic acid content ranged in the year 2010 from 3.67 to 7.55% and in the year 2011 from 4.92 to 8.07%. Via statistical analyses two chemotypes of essential oil were found: chemotype citral and chemotype β-caryophyllene oxide. Ploidy was determined for all genotypes and two cytotypes were found: diploid 2n = 2x = 32 (62 of 68 genotypes) and triploid 2n = 3x = 48 (6 of 68 genotypes). 相似文献