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91.
Morphohistological features of the tubular organs of the Myocastor coypus (coypu) female reproductive tract were studied. Specimens came from breeding farms with yard breeding systems. The analysis of the organs was made by histological methods and by macro and microscopic measurement techniques. The animals showed oviducts with macro and microscopically differentiable regions. Their mucosa showed primary branched folds in the ampullar sector. In the rest of the oviduct tract these folds were only of the primary type. The double uterus showed regional variations in the lumen, endometrial glands along the whole surface and a wide fibromuscular cervix with pseudoglands. The endocervical mucosa made clear a complex system of folds covered by a mucus-secreting epithelium. In the long vagina of the coypu a folded, rugose and irregular mucosa was observed. 相似文献
92.
93.
Veterinary Research Communications - The current study aimed at estimating the direct (condemned offal) and indirect (meat, milk, and fecundity losses) production losses due to cystic... 相似文献
94.
Campos FR Januário AH Rosas LV Nascimento SK Pereira PS França SC Cordeiro MS Toldo MP Albuquerque S 《Fitoterapia》2005,76(1):26-29
Crude extracts and fractions of Bertholletia excelsa stem barks were tested for trypanocidal activity. Acetone and methanol extracts showed significant in vitro trypanocidal activity against trypomastigote form of Trypanosoma cruzi since in the concentration of 500 microg/ml, the parasites were reduced in 100% and 90.3% respectively, whereas the triterpene betulinic acid pure isolated from hexane extract presented 75.4%. 相似文献
95.
Antibacterial activity of seed proteins of Robinia pseudoacacia 总被引:1,自引:0,他引:1
A low molecular weight cationic peptide was isolated from Robinia pseudoacacia seed and tested in vitro against seven bacteria (Corynebacterium michiganense, Staphylococcus aureus, Bacillus subtilis, Erwinia carotovora subsp. carotovora, Pseudomonas syringae pv syringae, Xanthomonas campestris pv campestris, and Escherichia coli). The peptide inhibited the growth of the tested strains. The effective concentrations required for 50% inhibition of bacterial growth ranged between 20 and 120 microg ml(-1) protein. S. aureus was found to be the most sensitive strain, however, E. coli was not affected much when compared with others. Reduction of antibacterial activity of the peptide with CaCl2 addition into the growth medium was also observed. 相似文献
96.
97.
Characteristics and decomposition rates of pruning residues from a shaded coffee system in Southeastern Brazil 总被引:1,自引:0,他引:1
In the Zona da Mata Mineira of Southeastern Brazil the development of sustainable land requires the integration of crops with trees. The objectives of this study then were to (i) characterize prunings from the main tree species in an agroforestry system; (ii) determine the effects of the physical and chemical characteristics of the prunings on their decomposition patterns in the laboratory; (iii) assess the effect of mixing leaves of different species on decomposition rates; and (iv) propose a decomposition index for the residues studied. The study was carried out with pruning residues from Cajanus cajan, Solanum variable, Cassia ferruginea, Piptadenia gonoacantha, Croton urucurana, and Melinis multiflora. The materials were characterized for total C, N, P, Ca, Mg and K contents; lignin, cellulose, hemicellulose and soluble polyphenols contents. The pruning residues had high polyphenols and lignin contents, high C:N and C:P ratios, and low contents of Ca, Mg, and K. The low decomposition rates of the prunings were related to the P, K, hemicellulose and polyphenol contents. The rates of N mineralization from most of the residues indicate that there is a potential to supply the needs of a crop of maize. The residues of some species, if decomposed alone, would not supply sufficient nutrients, and need to be mixed with leaves of other species.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
98.
Dr. A. Ş. Tunçbilek 《Journal of pest science》1995,68(2):37-38
The effect of gramma radiation on the rice weevil,Sitophilus oryzae (L.) was studied. Adults were subjected to 12 doses ranging from 0 to 180 Gy of gamma radiation from a60Co source. The time to onset of death and the duration of the period of mortality were investigated. Survival of the adults was decreased with increase of the doses. LD50 and LD99,9 values were calculated.With one figure and one table 相似文献
99.
The North American long-term soil productivity experiment: Findings from the first decade of research 总被引:1,自引:0,他引:1
Robert F. Powers D. Andrew Scott Felipe G. Sanchez Richard A. Voldseth Deborah Page-Dumroese John D. Elioff Douglas M. Stone 《Forest Ecology and Management》2005,220(1-3):31-50
First decade findings on the impacts of organic matter removal and soil compaction are reported for the 26 oldest installations in the nation-wide network of long-term soil productivity sites. Complete removal of surface organic matter led to declines in soil C concentration to 20 cm depth and to reduced nutrient availability. The effect is attributed mainly to the loss of the forest floor. Soil C storage seemed undiminished, but could be explained by bulk density changes following disturbance and to decomposition inputs of organic C from roots remaining from the harvested forest. Biomass removal during harvesting had no influence on forest growth through 10 years. Soil compaction effects depended upon initial bulk density. Soils with densities greater than 1.4 Mg m−3 resisted compaction. Density recovery was slow, particularly on soils with frigid temperature regimes. Forest productivity response to soil compaction depended both on soil texture and the degree of understory competition. Production declined on compacted clay soils, increased on sands, and generally was unaffected if an understory was absent. 相似文献
100.
Mathieu Jonard Frédéric André François Jonard Nicolas Mouton Pierre Procès Quentin Ponette 《Annals of Forest Science》2007,64(2):141-150
Total Soil Respiration (TSR) was measured in pure and mixed stands of oak and beech and was partitioned into two contributions using the forest floor removal technique: Mineral Soil Respiration (MSR) and Forest Floor Respiration (FFR). In addition, laboratory incubations of the forest floor and the Ah horizon were performed to evaluate the heterotrophic respiration and the DOC production of these horizons. The relationships between soil temperature and the various soil respiration contributions in the three stands were compared using Q 10 functions. In situ, significant differences (α = 0,05) between stands were observed for the R 10 parameter (respiration rate at 10 °C) of the TSR, MSR and FFR contributions, while only the temperature sensitivity (Q 10) of TSR was significantly affected by stand composition. The effect of soil water content was only significant on MSR and followed different patterns according to stand composition. Under controlled conditions, the R 10 of the forest floor and of the Ah horizon varied with stand composition and the Q 10 of the forest floor decreased in the order: oak (2.27) > mixture (2.01) > beech (1.71). 相似文献