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排序方式: 共有104条查询结果,搜索用时 343 毫秒
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Jean K. Frazho DVM John Graham MVB MSC DVR Diplomate ACVR & ECVDI Jeffrey N. Peck DVM Diplomate ACVS Jacek J. De Haan DVM Diplomate ACVS & ECVS 《Veterinary surgery : VS》2010,39(7):829-832
Objective: To determine if a secondary center of ossification (SCO) of the anconeal process is present in skeletally immature dogs that do not develop an ununited anconeal process (UAP). Study Design: Case series. Animals: Dogs 77–154 days of age with conditions other than developmental disease of the elbow (n=78 dogs; total elbows=100). Methods: Mediolateral radiographic projections of the elbow were reviewed for presence or absence of a SCO of the anconeal process. Results: A SCO was radiographically evident in 16% of elbows from breeds that have been reported to be affected by UAP. The appearance of the SCO was different to an UAP fragment. None of the elbows with SCO of the anconeal process developed UAP. A SCO was not present in any small breed dogs. Conclusions: A SCO of the anconeal process is uncommon in medium and large breed dogs and the presence of a SCO does not indicate that UAP will develop. Clinical Relevance: Because radiographic diagnosis of a SCO of the anconeal process and UAP lesions have distinct appearances, an earlier diagnosis of UAP is possible. 相似文献
23.
Monika Jamioł Jacek Wawrzykowski Wioleta Mojsym Martina Hoedemaker Marta Kankofer 《Reproduction in domestic animals》2020,55(9):1093-1102
The activity of glycosidases is crucial for the function and biological activity of proteins conjugated with sugar moieties, which play an important role in adhesion of cells during attachment and detachment of the foetal membranes. The aim of study was to describe the ability of bovine placental tissues to break down O-glycosidic bonds in different glycoproteins by the determination of activity of β-galactosidase, α-l-fucosidase, β-N-acetyl-hexosaminidase and sialidase in early–mid-pregnancy as well as at parturition with released and retained foetal membranes. Moreover, the availability of substrates for these glycosidases in placental homogenates was evaluated. Placental samples were collected from pregnant (2–4 months) cows in slaughterhouse (n = 8) as well as during Caesarean section and divided into released foetal membranes (n = 8) and retained foetal membranes (n = 8). Tissue homogenates were subjected to spectrofluorimetric and spectrophotometric determinations of enzyme activities as well as electrophoretic separations. Enzyme activities expressed changes within examined time with significant (p < .05) differences between pregnancy and physiological parturition in β-N-acetyl-hexosaminidase and α-l-fucosidase in foetal part of placenta while in maternal part only in the latter one. Decreasing tendency in enzyme activity was noticed in foetal part of retained samples in comparison with released ones with significant (p < .05) differences in α-l-fucosidase activity. The analysis of staining of sugar moieties attached to selected proteins depicted availability of sugar molecules in examined tissues, but their patterns differed between samples. In conclusion, sugar moieties in conjugated proteins express changes in the course of pregnancy which is reflected by the alterations in activities of placental glycosidases. 相似文献
24.
AbstractThe utilization of prebloom tissues to predict nutrition of apple (Malus domestica Borkh.) trees is limited. Therefore, the aim of this study was to assess the possible use of mineral analyses of the prebloom spur leaves and flowers to forecast the nutrition of ‘Idared’ apple trees in the mid-summer (based on the leaves from current-season shoots). The prebloom leaf concentrations of phosphorus, potassium, magnesium, boron and manganese were positively correlated with those in the summer leaves. The significant relationships between nitrogen, calcium, boron, and manganese in the flowers and those in the mid-summer leaves were also found. However, only the relationship between boron in the prebloom spur leaves and in the summer leaves was sufficiently strong. The calculated optimal range of boron in the prebloom spur leaves was 20–25?mg kg?1. 相似文献
25.
Jacek Wawrzykowski Anna Rapacz‐Leonard Dariusz Wicek Marta Kankofer Tomasz Janowski 《Reproduction in domestic animals》2019,54(12):1543-1551
Protein profile of the placenta expresses its function and maintenance. Any alterations can be reflected in qualitative and quantitative changes in this profile. The aim of the present study was the evaluation of protein profile in the placenta of mares suffering from the retention of foetal membranes (FMR) by two separation methods and the comparison with physiologically released tissues. Placentas from 14 healthy, heavy draft mares were collected immediately after the expulsion of newborn. Tissues after homogenization and staining with fluorescent dyes were subjected to electrophoretic as well as chromatographic separation. Electrophoretic gels were statistically analysed for the presence and abundance of examined proteins, while some proteins were identified in chromatographic fractions. Out of 248 spots detected in endometrium, 38 differed significantly between FMR and control animals, while in allantochorion, respective values reached 241 and 27 spots (p < .05). Among identified proteins that expressed higher abundance in endometrium of FMR mares than control animals were prostaglandin reductase, dehydrogenase/reductase SDR family, and placental growth factor. These proteins are involved in regulation of parturition. Additionally, the following proteins responsible for physiological activity of a cell—guanine methyl transferase, aspartyl/asparaginyl beta‐hydroxylase and GTP‐binding protein, were identified. These proteins expressed higher abundance in allantochorion of FMR mares than in controls. This preliminary study confirmed the disturbances in protein pattern between foetal membranes in FMR and healthy mares. Further qualitative and quantitative experiments are necessary to deepen our knowledge on the mechanisms of the retention of foetal membranes in mares. 相似文献
26.
Mapping Spatial Patterns with Morphological Image Processing 总被引:4,自引:3,他引:1
Peter Vogt Kurt H. Riitters Christine Estreguil Jacek Kozak Timothy G. Wade James D. Wickham 《Landscape Ecology》2007,22(2):171-177
We use morphological image processing for classifying spatial patterns at the pixel level on binary land-cover maps. Land-cover
pattern is classified as ‘perforated,’ ‘edge,’ ‘patch,’ and ‘core’ with higher spatial precision and thematic accuracy compared
to a previous approach based on image convolution, while retaining the capability to label these features at the pixel level
for any scale of observation. The implementation of morphological image processing is explained and then demonstrated, with
comparisons to results from image convolution, for a forest map of the Val Grande National Park in North Italy. 相似文献
27.
Frederick Cubbage Patricio Mac Donagh José Sawinski Júnior Rafael Rubilar Pablo Donoso Arnaldo Ferreira Vitor Hoeflich Virginia Morales Olmos Gustavo Ferreira Gustavo Balmelli Jacek Siry Mirta Noemi Báez José Alvarez 《New Forests》2007,33(3):237-255
Timber investment returns were estimated for the principal exotic and selected native species in the Southern Cone of Latin
America and in the Southern United States. Exotic eucalyptus plantations in South America were most profitable, with internal
rates of returns (IRRs) ranging from 13% to 23%, followed by exotic loblolly pine, with IRRs from 9% to 17%. Average loblolly
pine plantation returns in the US South were less profitable, with an IRR of about 9.5%, and natural forest management in
the South had IRRs of 4% to 8%. Subtropical native species plantations of the best araucaria and nothofagus species had reasonable
financial returns, with IRRs ranging from 5% to 13%. Subtropical or tropical native forests had fewer commercial timber species,
and had much lower growth rates and returns. Their IRRs were less than 4%, or even negative for unmanaged stands. State subsidy
payments for forest plantations or for timber stand improvements increased IRRs somewhat and reserving areas for environmental
protection reduced their IRRs slightly. Including land costs in the cash flows decreased these internal rates of return substantially.
Natural stand returns in Latin America were much less than those of plantations, but management of those stands offered better
rates of return than only holding the land. 相似文献
28.
We tested the effects of forest management type (managed vs. unmanaged) on the abundances of Ips typographus (L.) (Col., Curculionidae, Scolytinae) and related parasitoids and predators reared from spruce bolts exposed in Białowieża,
Poland. Habitat availability for these species differed between forest types mainly as a result of regular sanitary fellings
occurring in managed forests. Populations of the common polyphagous insect predators Paromalus paralellepipedus (Herbst) and Plegaderus vulneratus (Panz.) (Col., Histeridae) or parasitoids Rhopalicus tutela (Walk.), Dinotiscus eupterus (Walk.) and Roptrocerus xylophagorum Ratz. (Hym., Pteromalidae) related to I. typographus did not differ between managed and unmanaged forests. Only Thanasimus spp. (Col., Cleridae) was significantly more abundant in managed forest, possibly because it was favored by the more open,
sunny stands. However, the experiment was performed in stands where spruce is only a minor component and during the non-epidemic
phase of the bark beetle population, so further experiments may be necessary to determine if the effects of sanitary fellings
are greater in different forest types and at different stages of the population cycle. 相似文献
29.
Yano J Kern J Sauer K Latimer MJ Pushkar Y Biesiadka J Loll B Saenger W Messinger J Zouni A Yachandra VK 《Science (New York, N.Y.)》2006,314(5800):821-825
The oxidation of water to dioxygen is catalyzed within photosystem II (PSII) by a Mn(4)Ca cluster, the structure of which remains elusive. Polarized extended x-ray absorption fine structure (EXAFS) measurements on PSII single crystals constrain the Mn(4)Ca cluster geometry to a set of three similar high-resolution structures. Combining polarized EXAFS and x-ray diffraction data, the cluster was placed within PSII, taking into account the overall trend of the electron density of the metal site and the putative ligands. The structure of the cluster from the present study is unlike either the 3.0 or 3.5 angstrom-resolution x-ray structures or other previously proposed models. 相似文献
30.
Nawrotek P Czernomysy-Furowicz D Borkowski J Fijałkowski K Pobucewicz A 《Veterinary microbiology》2012,155(2-4):434-437
The aim of this study was to demonstrate the effect of auto-vaccine therapy on selected properties of Staphylococcus aureus strains, isolated from milk of cows with subclinical mastitis. The experiment was based on auto-vaccines which were prepared from S. aureus strains isolated from 16 cows. S. aureus strains isolated from cows on the 7th, 21st and 35th day following auto-vaccination, were analyzed phenotypically and genotypically. The isolated strains represented 17 biotypes all belonging to one clonal type. Increases of new biotypes of S. aureus were detected on the 35th day of therapy. Among 48 re-isolated strains, 18.75% (9/48) revealed single and 12.50% (6/48) multiple phenotypical changes. The present study demonstrated that during auto-vaccine therapy, S. aureus strains can change phenotypically, pointing out the necessity for using precise diagnostic methods, that would make possible a better assessment of the used therapy. 相似文献