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21.
Mirosław Cieśla Robert Jończyk Dariusz Gozdowski Jerzy Śliwiński Jacek Rechulicz Wojciech Andrzejewski 《Aquaculture International》2014,22(1):77-88
Three groups (wild—WS, semi-pond—SPS, and pond-cultured—PS) of ide Leuciscus idus (L.) were examined. Each group consisted of 30 females and 10 males, aged 5–8 years. All groups were stimulated with two agents: carp pituitary homogenate (CPH) and a synthetic hormonal preparation Ovopel. The amount of ovulating females decreased in conjunction with females’ domestication level, mainly because of very low efficacy of CPH for pond-reared ide stimulation. The percentage of ovulating females stimulated with Ovopel (97.0 %) was significantly higher comparing to CPH (63.0 %). No significant differences were found in latency time between the groups but spawning synchronization increased in conjunction with ide domestication. The positive correlation between domestication level and latency time, i.e., the higher the domestication level, the higher the latency time, was stated. No significant differences were found in PGSI as well as in total volume of obtained eggs, but groups differed significantly in the number of dry eggs and in number of swollen egg. Significant negative correlation between domestication level and number of swollen eggs, i.e., the higher the domestication level, the lower the number of eggs, was detected. The survival rate at the eyed stage was the highest in WS group (60.4 %) and PS group (57.7 %), and was significantly higher than in SPS group (51.8 %). Eggs obtained after CPH stimulation had higher survival rate at the eyed-egg stage (60.3 %) than eggs obtained from the fish stimulated with Ovopel (53.0 %). The data suggest that some form of domestication appeared in ide cultivated for several generations in carp pond. 相似文献
22.
Joanna Mucha Andrzej M. Jagodziński Bartosz Bułaj Piotr Łakomy Adrian M. Talaśka Jacek Oleksyn Marcin Zadworny 《Annals of Forest Science》2018,75(1):22
Key message
Quercus robur seedling mass was affected more by planting density than by taproot pruning. Root pruning enhanced stem biomass at the expense of roots in later growth stages. Alteration of biomass allocation due to nursery practices may result in greater susceptibility to injury and death of the seedlings under unfavorable environmental conditions.Context
Plants adjust their growth and modulate the resource allocation in response to applied treatments and environmental conditions.Aims
The aim was to examine how taproot pruning in seedlings grown at different densities affected long-term growth of Quercus robur.Methods
Seedlings, sown as acorns at two planting densities, with or without pruned roots were harvested in the second, fourth, and fifth years of growth. The effect of root pruning on biomass allocation was determined by measuring leaf, stem, and root mass fractions; carbohydrate concentrations in the roots; and C/N ratios. Specific leaf area and root length were also determined to assess morphological adaptations to growth conditions.Results
Total seedling mass was affected more by planting density than by taproot pruning. After 4 years of growth, root mass fractions were lower and stem mass fractions were greater in seedlings planted at a higher density. Five-year old root-pruned seedlings also had a lower root mass fraction and higher stem mass fractions than unpruned seedlings. Specific root length was not affected by root pruning or planting density.Conclusion
Decrease of relative root biomass with simultaneous increase of stem biomass may be a long-term consequence of taproot pruning of Q. robur, and the effects may manifest years after the seedling stage.23.
24.
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
25.
M Ugliano JB Dieval TE Siebert M Kwiatkowski O Aagaard S Vidal EJ Waters 《Journal of agricultural and food chemistry》2012,60(35):8561-8570
The evolution of different volatile sulfur compounds (VSCs) during bottle maturation of two Shiraz wines submitted to controlled oxygen exposure prior to bottling (through micro-oxygenation, MOX) and postbottling (through the closure) was investigated. H(2)S, methyl mercaptan (MeSH), and dimethyl sulfide (DMS) were found to increase during aging. Lower postbottling oxygen exposure, as obtained by different degrees of oxygen ingress through the closure, resulted in increased H(2)S and methyl mercaptan. In one wine MOX increased the concentration of H(2)S and methyl mercaptan during maturation. Dimethyl disulfide and DMS were not affected by any form of oxygen exposure. Overall, postbottling oxygen had a stronger influence than MOX on the evolution of VSCs. Data suggest that dimethyl disulfide was not a precursor to methyl mercaptan during bottle maturation. For the two wines studied, a consumption of oxygen of 5 mg/L over 12 months was the most effective oxygen exposure regimen to decrease accumulation of MeSH and H(2)S during bottle aging. 相似文献
26.
C. R. Brown S. Kwiatkowski M. W. Martin P. E. Thomas 《American Journal of Potato Research》1988,65(11):633-638
In vitro shoot tips from PVS-infected potato breeding clones and cultivars were exposed to a constant temperature of 34 C and 8,100 lux light. Meristems were excised from heat-treated shoot tips after 3 to 7 weeks of heat therapy. Serological tests were performed on shoot tips derived from meristems excised from heat-treated shoot tips. Additional serological tests, combined with bioassays, applied to six-week-old pot-grown cuttings derived from these shoot tips, did not detect PVS in 19 out of 21 clones given heat therapy. A 90% rate of eradication was achieved. 相似文献
27.
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
28.
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
29.
30.
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