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91.
First morphological characterization of 'Candidatus Mycoplasma turicensis' using electron microscopy
Willi B Museux K Novacco M Schraner EM Wild P Groebel K Ziegler U Wolf-Jäckel GA Kessler Y Geret C Tasker S Lutz H Hofmann-Lehmann R 《Veterinary microbiology》2011,149(3-4):367-373
At least three haemotropic mycoplasmas have been recognized in cats: Mycoplasma haemofelis (Mhf), 'Candidatus Mycoplasma haemominutum' (CMhm) and 'Candidatus M. turicensis' (CMt). The latter was originally identified in a Swiss pet cat with haemolytic anaemia and shown to be prevalent in domestic cats and wild felids worldwide using molecular methods. So far, there has been no confirmatory morphological evidence of the existence of CMt presumably due to low blood loads during infection while CMhm has only been characterized by light microscopy with discrepant results. This study aimed to provide for the first time electron microscopic characteristics of CMt and CMhm and to compare them to Mhf. Blood samples from cats experimentally infected with CMt, CMhm and Mhf were used to determine copy numbers in blood by real-time PCR and for transmission and scanning electron microscopy. High resolution scanning electron microscopy revealed CMt and CMhm to be discoid-shaped organisms of 0.3 μm in diameter attached to red blood cells (RBCs). In transmission electron microscopy of CMt, an oval organism of about 0.25 μm with several intracellular electron dense structures was identified close to the surface of a RBC. CMhm and CMt exhibited similar morphology to Mhf but had a smaller diameter. This is the first study to provide morphological evidence of CMt thereby confirming its status as a distinct haemoplasma species, and to present electron microscopic features of CMhm. 相似文献
92.
93.
Elisabeth V. Moore DVM Robert Weeren DVM MS DACVS Matthew Paek VMD MS DACVR 《Veterinary surgery : VS》2020,49(1):146-154
94.
Teodora Todorcic Vekic Shahid Nadeem Lars Molstad Vegard Martinsen Elisabeth Gautefall Hiis Lars Bakken Tobias Rütting Leif Klemedtsson Peter Dörsch 《Soil Use and Management》2023,39(3):1082-1095
Liming of acidic agricultural soils has been proposed as a strategy to mitigate nitrous oxide (N2O) emissions, as increased soil pH reduces the N2O/N2 product ratio of denitrification. The capacity of different calcareous (calcite and dolomite) and siliceous minerals to increase soil pH and reduce N2O emissions was assessed in a 2-year grassland field experiment. An associated pot experiment was conducted using homogenized field soils for controlling spatial soil variability. Nitrous oxide emissions were highly episodic with emission peaks in response to freezing–thawing and application of NPK fertilizer. Liming with dolomite caused a pH increase from 5.1 to 6.2 and reduced N2O emissions by 30% and 60% after application of NPK fertilizer and freezing–thawing events, respectively. Over the course of the 2-year field trial, N2O emissions were significantly lower in dolomite-limed than non-limed soil (p < .05), although this effect was variable over time. Unexpectedly, no significant reduction of N2O emission was found in the calcite treatment, despite the largest pH increase in all tested minerals. We tentatively attribute this to increased N2O production by overall increase in nitrogen turnover rates (both nitrification and denitrification) following rapid pH increase in the first year after liming. Siliceous materials showed little pH effect and had no significant effect on N2O emissions probably because of their lower buffering capacity and lower cation content. In the pot experiment using soils taken from the field plots 3 years after liming and exposing them to natural freezing–thawing, both calcite (p < .01) and dolomite (p < .05) significantly reduced cumulative N2O emission by 50% and 30%, respectively, relative to the non-limed control. These results demonstrate that the overall effect of liming is to reduce N2O emission, although high lime doses may lead to a transiently enhanced emission. 相似文献
95.
96.
Dipl. Ing. Elisabeth Schiessendoppler 《Potato Research》1987,30(2):349-360
Ohne Zusammenfassung 相似文献
97.
Wolfgang Henninger DR MED VET E. Mairi Frame BVMS DVR MRCVS Michael Willmann DR MED VET Hubert Simhofer DR MET VET Dieter Malleczek MAG MED VET Sibylle M. Kneissl DR MED VET Elisabeth Mayrhofer PROF DR MED VET 《Veterinary radiology & ultrasound》2003,44(3):269-276
Sinusitis is a common disorder in horses and may result from trauma, dental diseases, or space-occupying lesions. Radiography can only provide a limited amount of information. Computed tomography (CT) has been documented as an alternative imaging method. Eighteen horses (mostly Warmblood) with signs of chronic sinusitis were examined preoperatively with CT to assist in diagnosis of the underlying cause. There was a group of common CT features in horses with dental disease and sinusitis. The first molar was the most frequently affected maxillary cheek tooth. Hypoattenuation of the cementum, destruction of the enamel, and filling of the infundibular cavity with gas were the most frequent CT findings associated with caries. Gas bubbles within the bulging root area or fragmentation of the root in combination with swelling of the adjacent sinus lining were the most important CT features of dental decay. CT findings associated with sinusitis included excessive thickening of the respiratory epithelium in the rostral maxillary sinus; the caudal maxillary sinus was less often involved. The infraorbital canal, the nasomaxillary duct, and the frontomaxillary aperture were usually involved. The maxillary bone, however, especially the facial crest, was involved in nearly every horse, being characterized by endosteal sclerosis, thickening, periosteal reaction, and deformation leading to facial swelling in chronic infections. CT images allowed identification of involvement of individual teeth more clearly to reveal the diseased one for treatment. Three-dimensional imaging allowed improved understanding of the extent and severity of the pathologic change. 相似文献
98.
Andreas Spornberger Elisabeth Schüller Edina Vidéki György Végvári 《Erwerbs-Obstbau》2018,60(3):231-238
In autumn 2008, in the research orchard of the University of Natural Resources and Life Sciences in Vienna, the apple cultivar ‘Topaz’ was planted on the rootstocks M9 (clone T337) with and without ‘Rubinola’ as interstem, M26, M7 grafted at 25?cm and at 55?cm respectively, M111 and ‘Bittenfelder seedling’, trained as spindles and tested for eight years according to organic production rules. The trees on seeding grew very vigorously, followed by MM111 and M7 normally grafted; the M7 highly grafted trees showed less vigor, comparable with M26, while the trees on M9 with and without interstem grew very weakly. Tree losses were only observed on M9 without interstem. The highest yields per hectare were found on M7 normally grafted, followed by M26, M7 highly grafted and M9 without interstem. M7 highly grafted showed the highest single fruit weights, followed by MM111, at the other end were M9 with and without interstem, and M26. The rootstock M7 grafted at 55?cm combines a medium growth with high yield and good fruit quality and therefore can be recommended for dry areas like our site. M9 without interstem showed a higher specific yield and fruit firmness after storage compared to the variant with interstem. Whether these advantages for ‘Topaz’ on M9 can be combined with a higher grafting height as effective preventive method to control Phytophthora cactorum, has to be examined in further research. 相似文献
99.
Elisabeth Simone-Freilicher 《Veterinary Clinics of North America: Exotic Animal Practice》2008,11(1):125-37, vii
Adrenal gland disease in ferrets is unique to this species, with clinical signs and pathophysiology different from those seen in the dog. Its prevalence is increasing; 70% of pet ferrets in the United States were affected in 2003. The exact causes of the adrenal gland changes that lead to the disease are not known. Early oophorohysterectomies and neutering, combined with the artificially prolonged photoperiod experienced by indoor pet ferrets, and a possible genetic component, may be contributing factors. Signs of adrenal gland disease include progressive hair loss, pruritis, lethargy, atrophy, and, in female ferrets, vulvar swelling. An understanding of the signs and physiologic changes is necessary for diagnosis and treatment. A review of anatomy, physiology, and current surgical and medical options is presented. 相似文献
100.
Evaluation of the in vitro efficacy of hemodialysis,hemoperfusion, and the combined approach on the removal of metaldehyde from canine plasma 下载免费PDF全文