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181.
We evaluated fungal decay and mold resistance, leaching, and water absorption of nano-compounds and Paraloid B72® (PB72) in treated wood specimens to develop new methods of consolidation by combining nano-particles and consolidants. Scots pine wood specimens were treated with dispersions of nano-CuO, nano-ZnO, nano-B2O3, nano-TiO2, and nano-CeO2. PB72 treatments of nano-particle-treated wood specimens were then carried out by either vacuum or immersion for 24 h. Previously, decayed wood specimens were also consolidated with the nano-compounds and PB72. PB72 treatments reduced element release from treated wood specimens. Nearly all nano-compounds + PB72 treatments increased the biological performance of treated wood specimens against decay fungi tested. PB72-only treated wood specimens had the highest weight losses in decay tests. No improvements were obtained in mold resistance tests when the nano-compounds and PB72 were combined. In nano-compound-only treatments, unleached specimens showed slightly lower water absorption values compared to untreated control specimens. Incorporation of PB72 into nano-compound-treated wood specimens resulted in considerably lower water absorption and volumetric swell. In previously decayed specimens treated with the nano-compounds and PB72 solution, water absorption after 2-h immersion declined compared to control specimens. 相似文献
182.
183.
Ten normal equine isolated limbs were imaged using a knee coil in a 1.5 Tesla magnetic field, with short echo time sequences (TE < 15 ms). Magnetic resonance imaging was performed on each isolated limb in different positions, with and without extension of the metacarpophalangeal joint. Deep digital flexor tendon orientation ranged from 20 to 60 degrees in relation to the static magnetic field. Increased intratendinous signal intensity was observed when the angle between the deep digital flexor tendon and the constant magnetic field approached 55 degrees ("magic angle"). The increased signal intensity was independent from extension of the metacarpophalangeal joint. Recognition of the magic angle phenomenon is essential for proper evaluation of magnetic resonance imaging studies of the equine foot. 相似文献
184.
Virginie De Busscher DVM Denis Verwilghen DVM Graldine Bolen DVM Didier Serteyn DVM PhD dipECVA Valeria Busoni DVM PhD dipECVDI 《Journal of Equine Veterinary Science》2006,26(10):453-461
This retrospective study reports diagnostic findings in 74 horses with ultrasonographic diagnosis of femorotibial joint damage; it describes the ultrasonographic features of meniscal tears and determines the prevalence of medial or lateral meniscal involvement and of associated synovial effusions. Horses were classified into four groups: with medial meniscal damage, with lateral meniscal damage, with lesions in both menisci, and with no ultrasonographic evidence of meniscal damage. After ultrasonographic appearance, meniscal lesions were described as central degeneration, horizontal tear, partial oblique tear of the distal angle, combined horizontal and oblique tears, or complex tear. Meniscal protrusion or other associated ultrasonographic or radiographic abnormalities were recorded. Of the 74 horses, 54 (73%) had medial meniscal damage, 5 (6.75%) had lateral meniscal damage, 5 (6.75%) had lesions in both menisci, and 10 (13.5%) had no meniscal lesion. Meniscal protrusion occurred in 20 cases (27%). Horizontal tears were the most frequent type of meniscal lesion (26 horses). Complex lesions were found in 6 lateral menisci and 14 medial menisci. Lesions of the cranial meniscal ligaments were seen in 10 horses. Synovial effusion of one or several joint compartments was found in 51 cases (68.9%).This study demonstrates the high prevalence of meniscal tears and synovitis in horses with ultrasonographic evidence of femorotibial derangement. Based on this series of clinical cases, horizontal tears of the medial meniscus appear to be the most frequent soft tissue injury of the equine stifle. 相似文献
185.
Raffaella Tudisco Federico Infascelli Monica Isabella Cutrignelli Fulvia Bovera Caterina Morcia Primetta Faccioli Valeria Terzi 《Livestock Science》2006,105(1-3):12-18
The effect of the digestion process in the gastro-intestinal tract (GIT) of animal models on the fate and integrity of plant DNA has been widely evaluated since DNA availability and integrity is a key factor for hypothetical horizontal gene transfer of recombinant DNA from GM crop-derived feeds to animal and human gut microflora. In this study, plant DNA sequences from high and low copy number genes were monitored in GIT and tissues of buffaloes and rabbits. Using a real-time PCR approach to track plant DNA in animal samples, we demonstrated the persistence of fragmented plant DNA blood and tissues of buffaloes and rabbits raised with conventional feeding. 相似文献
186.
The fragment of the cytochrome b (cyt b) gene responsible for the binding site of QoI fungicides was sequenced for different Puccinia species by using DNA and RNA as template for PCR and RT-PCR, respectively. Degenerated primers for the cyt b gene amplified in P. recondita f.sp. tritici a 450 bp fragment, which was cloned and sequenced. At cDNA level, several Thermal Asymmetric InterLaced (TAIL)-PCR cycles were needed to produce a 996 bp long fragment, which corresponded to almost the whole cyt b gene (about 1160-1180 bp, without introns). This fragment was sequenced and specific primers were designed. Amplification with cyt b specific primers using genomic DNA as template revealed the presence of an intron of about 1500 bp length after the codon for glycine at amino acid position 143. By using the same primer pair, the cyt b gene fragment was amplified and sequenced both at cDNA and genomic DNA level also for other rust species, including P. graminis f.sp. tritici (length: 506 bp), P. striiformis f.sp. tritici (755 bp), P. coronata f.sp. avenae (644 bp), P. hordei (660 bp), P. recondita f.sp. secalis (687 bp), P. sorghi (709 bp), and P. horiana (478 bp). At the same position as for P. recondita f.sp. tritici, an intron of about 1500-1600 bp length was detected also in all other Puccinia species. High homologies were observed among all Puccinia species for both the exonic and intronic fragments of the cyt b gene. Specific primers for the cyt b gene of all eight Puccinia species were developed, which easily amplified the fragment of the gene including all possible mutations known to confer resistance to QoIs in several plant pathogens. However, in all tested isolates of the Puccinia species included in this study, the sequence of cyt b gene fragment did not contain any point mutations. 相似文献
187.
Elena Riccardi Valeria Grieco Valeria Greco Sara Verganti Mario Finazzi 《Journal of veterinary diagnostic investigation》2007,19(4):431-435
In humans and canines, the morphology of granulosa cell tumors is extremely variable and causes diagnostic difficulties. In human pathology, immunohistochemistry has been widely used for the diagnosis of granulosa cell tumors, whereas, limited studies are present in canine species. The aim of this study was to investigate the expression of cytokeratins, vimentin, and inhibin-alpha in canine normal ovaries, epithelial ovarian tumors, and granulosa cell tumors to establish an immunohistochemical panel for the differential diagnosis of ovarian tumors. Formalin-fixed, paraffin-embedded tissue sections from 4 normal ovaries, 8 granulosa cell tumors, and 6 epithelial ovarian tumors (2 adenomas and 4 adenocarcinomas) sections were obtained and stained with hematoxylin and eosin and immunohistochemically for cytokeratin AE1/AE3, cytokeratin 7, vimentin, and inhibin-alpha. In normal ovaries, cytokeratin 7, cytokeratin AE1/AE3, and vimentin were expressed in the surface epithelium. Granulosa cells were negative for cytokeratin 7 and displayed variable expression of vimentin, cytokeratin AE1/AE3, and inhibin-alpha toward follicular maturation. Granulosa cell tumors were negative for cytokeratin 7 and positive for inhibin-alpha. Conversely, ovarian epithelial cells tumors were positive for cytokeratin 7 and negative for inhibin-alpha. Both granulosa and epithelial cell tumors displayed variable expression of vimentin. Cytokeratin AE1/AE3 was expressed by all epithelial-derived tumors and 6 of 8 granulosa cell tumors. The results of this study suggest that useful immunohistochemical markers to distinguish epithelial ovarian tumors from granulosa cell tumors are cytokeratin 7 and inhibin-alpha. 相似文献
188.
Tiziana Amoriello Valeria Turfani Vincenzo Galli Francesco Mellara Marina Carcea 《Cereal Chemistry》2016,93(4):364-368
Gluten aggregation properties were investigated by means of the GlutoPeak device, a viscometer recently proposed as a rapid and sensitive test for measurement of wheat flour technological performance. In this study, 62 soft wheat flour samples of different quality and end use were utilized to evaluate if the GlutoPeak parameters could adequately predict chemical and rheological characteristics of soft wheat flour dough, that is, protein content measured by the Kjeldahl method, dough strength measured by a Chopin alveograph, and dough stability and water absorption measured by a Brabender farinograph. Linear correlation analysis showed that most GlutoPeak curve parameters were strongly correlated with protein content, dough strength, and water absorption. The statistical models, obtained by a stepwise multiple regression method, showed the GlutoPeak device to be a promising tool to characterize wheat flour (Radj2 = 0.84 for protein content, Radj2 = 0.71 for dough strength, and Radj2 = 0.67 for water absorption). The rather high accuracy of the prediction models for the three mentioned parameters confirmed that GlutoPeak parameters are well correlated with other frequently used flour quality parameters and are able to describe flour technological performance. 相似文献
189.
Chiara Bergamino Anne‐Laure Etienne Valeria Busoni 《Veterinary radiology & ultrasound》2015,56(4):456-461
An accurate method for guiding injections into the canine hip would facilitate diagnostic localization of lameness and targeted treatments. Ultrasound‐guided hip injections are commonly used in humans and large animals. Aims of this prospective study were to describe ultrasound (US) anatomy of the adult canine hip and determine the feasibility and accuracy of intra‐articular placement of injectate using US‐guidance. Seven adult dogs were used to describe US anatomy, five dog cadavers were used to assess the feasibility of the injection technique and 11 dog cadavers were used to assess accuracy of injections. For the accuracy test, 22 joints were injected with iodinated contrast medium by three operators with different experience. With dogs in lateral recumbency, the hyperechoic femoral head surface was identified by following the femoral neck from the greater trochanter or the acetabular rim was localized by following caudally the ilium from the iliac wing. An anechoic gap between the femoral head and acetabular surface represented the joint. The capsule was visible as a triangular echoic structure and the femoral head articular cartilage appeared as an anechoic band. The needle was inserted axial to the greater trochanter and directed in a dorsolateral–ventromedial direction toward the joint space and then pushed through the capsule. Based on postinjection radiography, accuracy was 81.8% at first attempt and 100% at second attempt. This study indicated that US‐guided injection is a feasible and accurate technique for injecting the adult canine hip. Future studies in live dogs are needed to assess safety and efficacy. 相似文献
190.
First detection of canine parvovirus type 2c in South America 总被引:8,自引:0,他引:8
Pérez R Francia L Romero V Maya L López I Hernández M 《Veterinary microbiology》2007,124(1-2):147-152
Since its sudden emergence in the early 1970s, canine parvovirus type-2 (CPV-2) has been evolving through the generation of novel genetic and antigenic variants (CPV-2a/b/c and a number of additional mutations) that are unevenly distributed throughout the world. In order to develop strategies to control the spread of these variants and to understand virus evolution is fundamental to genotype field isolates from different geographic locations. In the present paper we have examined 25 isolates of CPV from clinical samples of Uruguayan dogs collected during year 2006. A fragment of the VP2 gene of the virus was analyzed using polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP) and DNA sequence analysis. Out of the 25 isolates analyzed, only one was characterized as CPV-2a and 24 were characterized as CPV-2c, indicating that this type is currently the prevalent field CPV circulating in Uruguay. This is the first report of CPV-2c in the American continent and it also represents the highest frequency of this type observed in a dog population so far. Its presence in South American supports the assumption that CPV-2c is reaching a worldwide distribution as occurred with 2a/2b antigenic types. 相似文献