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91.
92.
Sacral osteochondrosis in two German Shepherd Dogs 总被引:1,自引:1,他引:0
KR Mathis M Havlicek JB Beck RD Eaton-Wells FM Park 《Australian veterinary journal》2009,87(6):249-252
Two young adult male castrated German Shepherd Dogs were referred for evaluation of intermittent episodes of hindlimb pain. Physical examination suggested lumbosacral stenosis, and plain radiographs and computed tomography revealed lesions consistent with sacral osteochondrosis. One dog had osteochondral fragments removed surgically; the other was managed conservatively. The surgically treated dog had complete resolution of clinical signs whereas the dog managed conservatively had repeated episodes of mild pain and received one short course of non-steroidal anti-inflammatory medication in 18 months. Sacral osteochondrosis has not been previously reported in Australia. 相似文献
93.
American chestnut trees once dominated vast areas of deciduous forest in eastern North America, but the exotic chestnut blight almost eliminated the species from the region. Introduction of blight-resistant American chestnut hybrids will probably start in the next decade after many years of tree breeding. What were the historic effects of chestnut on forest soils, and what changes may follow reintroduction of hybrid chestnuts? A site in southern Wisconsin provided an opportunity to examine the effect of chestnut trees on soil properties. At this site, 600 km northwest of chestnut's historic distribution, naturalized chestnuts have spread throughout an intact mixed-species forest from nine planted trees. The site contains soil developed on a silty loess-mantled ridge that abuts sandier hillslopes, allowing the effects of individual chestnuts to be examined on two soil types. I sampled and analyzed forest floor and mineral soils beneath canopies of individual American chestnuts and the surrounding mixed-species deciduous forest on fine-silt and sandy-loam soil types. On sandy loam soils, total soil carbon (C) and nitrogen (N), inorganic N and net mineralization and nitrification rates were 10–17% higher beneath chestnut canopies compared to soils beneath mixed-species deciduous forest. The pool of total soil N beneath chestnut canopies was positively related to the silt content of the sandy loam soils. In contrast, there were no differences between properties of chestnut canopy and mixed-species deciduous forest soils on the fine silt texture class. On sandy loam soil conditions common throughout the pre-blight distribution of American chestnut, soil biogeochemical processes differ beneath individual chestnut trees relative to a diverse mixture of deciduous species. These findings suggest that widespread chestnut reintroduction has the potential to alter both stand- and watershed-scale processes. 相似文献
94.
An epornitic of fowl cholera involving turkey flocks of several farms within a 15-mile radius in Utah was studied. Pasteurella multocida strains isolated from birds in affected flocks were antigenically characterized as A:1, A:3, and B:4, based on capsular sero-grouping and somatic serotyping results. Experimental exposure of poults with each of two strains representing the rarely reported capsular group B indicated that both were virulent. 相似文献
95.
Sialomucin Complex (Muc4) Expression in Porcine Endometrium During the Oestrous Cycle and Early Pregnancy 总被引:1,自引:0,他引:1
The non‐invasive type of implantation in the pig is characterized by the maintenance of a thick glycocalyx coating on the uterine epithelial surface microvilli. Present study investigated the alteration in the sialomucin complex (Muc4) expression during the oestrous cycle and early pregnancy in the pig. Endometrial tissue samples were immunostained with the primary antibody to the Muc4 transmembrane subunit ASGP‐2. Muc4 immunostaining increased in the surface and glandular epithelia between days 5 and 10 of oestrous cycle. Immunostaining continued to increase on day 12 with the greatest intensity of uterine Muc4 immunostaining detected on day 15 of the oestrous cycle and early pregnancy. Endometrial Muc4 expression in cyclic gilts decreased dramatically during early proestrous but continued to remain abundant in the surface and glandular epithelium of pregnant gilts during the period of conceptus attachment to the uterine surface. 相似文献
96.
Tomographic imaging indicates that slabs of subducted lithosphere can sink deep into Earth's lower mantle. The view that convective flow is stratified at 660-kilometer depth and preserves a relatively pristine lower mantle is therefore not tenable. However, a range of geophysical evidence indicates that compositionally distinct, hence convectively isolated, mantle domains may exist in the bottom 1000 kilometers of the mantle. Survival of these domains, which are perhaps related to local iron enrichment and silicate-to-oxide transformations, implies that mantle convection is more complex than envisaged by conventional end-member flow models. 相似文献
97.
98.
Abstract Extract Among the puzzling aspects of the recently described autosomal recessive polycystic kidney disease (ARPKD) of sheep (Johnstone et al 2005) is the multiplicity of organ systems affected and the phenotypic variations that occur between the various animal species. It has been shown in studies of other inherited polycystic kidney disease syndromes that the normal gene products of a mutant are likely to be involved in ciliary structure and function. The studies that have led to this recognition can be expected to eventually provide the basis for a better understanding of the functioning of this organelle, and the pathogenesis of lesions in the related diseases. It is well known that cilia are important in the perception of light, olfactory stimuli and sound and that motile cilia provide cell motility (e.g. sperm) and transport of mucus and other fluids. Recent research has indicated that the involvement of the primary cili-um/basal body complex is of central importance in the detection and cellular response to extracellular movement of fluid, critical phases of embryonic development, cell cycle regulation and maintenance of cell polarity. Confocal microscopic studies of renal cyst epithelium in ovine ARPKD have shown that only 30% of cells have a cilium and that these are often truncated (McGlashan et al 2005). The observation, although preliminary, strongly supports the argument that the mutant gene in this disease of sheep normally encodes for a protein essential for primary ciliary function. 相似文献
99.
100.
Paul R. Rhoades Jonathan B. Koch Lisette P. Waits James P. Strange Sanford D. Eigenbrode 《Journal of insect science (Online)》2016,16(1)
Since the mid-1990s, Bombus occidentalis (Green) has declined from being one of the most common to one of the rarest bumble bee species in the Pacific Northwest of the United States. Although its conservation status is unresolved, a petition to list this species as endangered or threatened was recently submitted to the U.S. Fish and Wildlife Service. To shed light on the conservation situation and inform the U.S. Fish and Wildlife Service decision, we report on the detection and abundance of B. occidentalis following bumble bee collection between 2012 and 2014 across the Pacific Northwest. Collection occurred from the San Juan Islands and Olympic peninsula east to northern Idaho and northeastern Oregon, excluding the arid region in central Washington. B. occidentalis was observed at 23 collection sites out of a total of 234. With the exception of three sites on the Olympic peninsula, all of these were in the southeastern portion of the collection range. 相似文献