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1.
Little is known of the importance of mineral levels in buffalo semen or the relationship of the level of various elements to spermatozoan activity. To establish a basis upon which further studies could be conducted, the accessory glands (seminal vesicles, prostate and bulbo-urethrals) of 43 buffalo bulls (2-4 years old) with intact testes and eight steers (3-4 years old) were analysed for their content of bulk and trace elements. The ash obtained from known weights of various accessory glands was used to determine the concentrations of Na and K using emission flame photometry. P was determined chemically, whereas Ca, Mg, Cu, Fe and Zn were assayed by atomic absorption spectrophotometry. The accessory glands of intact bulls varied significantly in the concentration of all elements except Fe. Ca and Cu were relatively more concentrated in the seminal vesicles. The prostate had the highest concentration of Zn, while the highest concentrations of Na, K, Mg and P were found in the bulbo-urethral glands. Age of the bulls had no marked effect on any of the elements studied except Cu which appeared to decrease significantly in older bulls. Seasonal variation was significant for the levels of K, Ca and Zn. Castration appeared to result in a highly significant reduction of Zn concentration in all accessory glands. 相似文献
2.
H. Abdou H. Marichatou J.‐F. Beckers I. Dufrasne M. Issa J.‐L. Hornick 《Journal of animal physiology and animal nutrition》2014,98(5):845-852
The aim of this study is to evaluate the efficacy of frozen Azawak colostrum supplementation on body weight (BW), average daily gain (ADG), reproductive parameters (mean age at first parturition, fertility, fecundity, prolificacy) and mortality rate among red kids. The study was conducted at the goat farm secondary centre of Maradi in Niger from September 2010 to September 2011. The control animals (n = 20) were left with their mother, while the treatment animals (n = 20) received in addition 50 ml/animal/day of bovine colostrum at birth and 15 ml/animal/day from d2 to d15. Weight was measured weekly from birth to d365. Mortalities were also recorded over the same period. For reproductive parameters, observations began at weaning (d197). Growth rate was higher (p < 0.001) in supplemented animal, and the treatment effects on ADG were observed up to 150 day after the end of supplementation. A similar long‐lasting trend was also observed in relation to the mortality rate (25% for ColG vs. 55% for ConG; p = 0.05). The age at first kidding tended to be lower in the treated group (13.8 ± 0.7 vs. 14.1 ± 0.8 month; p < 0.1). In conclusion, mild bovine colostrum supplementation induces a long‐lasting positive impact on growth rate and to a lower extent on reproduction parameters and survival rate. 相似文献
3.
In an attempt to evaluate whether breeding and selection for high yielding capacity changed the P requirement of modem wheat cultivars. the response of two wheat cultivars to different levels of P supply was investigated. A traditional cultivar (‘Peragis’) and a modern spring-wheat cultivar (‘Cosir’) were cultivated in a C-loess low in available P and high in CaCO3 in 120 cm high PVC tubes. In addition and for comparison, nutrient solution experiments were also conducted. Shoot growth, root growth. P uptake. P translocation and P distribution within the shoot at different developmental stages were compared. The grain yield of the modern cultivar ‘Cosir’ was higher at limiting and non-limiting P supply and. therefore, this cultivar can be considered as more P-efficient than the traditional cultivar. Grain yield reduction at low P supply was mainly due to an inhibition of tillering and thus lower number of ears per plant, whereas the number of grains per ear was hardly affected. Reduced tillering at low P supply could not be related to P concentrations in the shoot meristematic tissues which were generally much higher than in other plant tissues and kept at an elevated level even at limiting P supply. Root branching (1st order laterals) was reduced at limiting P supply in ‘Cosir’ but not in ‘Peragis’ which, generally, had lower numbers of laterals at the beginning of tillering. From the results it can be concluded that the main factors contributing to the higher P efficiency of the modern cultivar ‘Cosir’ are (i) efficient use of assimilates for root-growth characteristics which enhance P acquisition: enhanced root branching and thus smaller mean root diameter and longer root hairs, (ii) an efficient P uptake system, (iii) efficient remobilization of P from vegetative plant organs to the grains, and most importantly (iv) lower P requirement for grain yield formation because of lower ear number per plant but higher grain number per ear. 相似文献
4.
Bone marrow: the bursa equivalent in man? 总被引:6,自引:0,他引:6
Human bone marrow lymphoid cells, particularly when enriched with plasma cells, as in multiple myeloma, respond to pokeweed mitogen and to antiserum to immunoglobulin but not to phytohemagglutinin. Cells of patients with X-linked agammaglobulinemia of the bursal deficient type failed to respond to either pokeweed or to the antiserum to immunoglobulin. Leukocytes of the agammaglobulinemia patients however responded in a normal fashion to phytohemagglutinin. Just as the in vitro response to phytohemagglutinin is taken as an index of the thymus-dependent system, the in vitro response to both antiserum to immunoglobulin and pokeweed may be considered an index for the bursaldependent system. Human bone marrow, therefore, contains bursal cells and probably very few or no thymus cells. 相似文献
5.
6.
Ploidy manipulations and interspecific crosses have allowed considerable genetic progress in Musa breeding, but estimation
of genetic parameters for parental selection remains a major challenge. This study aimed to determine the components of genetic
variance and the relative contribution of genetic effects to phenotypic variation of yield and phenological traits in secondary
triploid hybrids from tetraploid–diploid crosses. The hybrids were evaluated in two consecutive growth cycles on a tropical
forest site. Non-genetic effects accounted for a large fraction of the variation observed for most traits, except bunch weight.
Partitioning of genetic variance into additive and dominance components confirmed the predominant role of additive genetic
effects on the expression of bunch weight, fruit filling time, fruit length, plant height, and number of leaves while primarily
non-additive effects accounted for suckering behavior and fruit circumference. Maternal general combining ability (GCA) effects
accounted for the additive genetic variation in plant height and number of leaves, suggesting that selection for these traits
should be carried out in tetraploid clones. Conversely, paternal GCA effects were the primary causes of genetic variation
for fruit filling time, bunch weight, and fruit length, suggesting that these characters should be selected for in diploid
clones. Specific combining ability (SCA) effects were observed for all traits, except fruit filling time, suggesting that
additional genetic gain could be achieved through recombinative heterosis for these traits. 相似文献
7.
Awad Walid S. El-Sayed Amr A. Mohammed Faten F. Bakry Noha M. Abdou Nadra-Elwgoud M. I. Kamel Mohamed S. 《Tropical animal health and production》2020,52(6):3173-3185
Tropical Animal Health and Production - Escherichia coli field isolates from calves were characterized and categorized into the most significant diarrheagenic pathotypes using polymerase chain... 相似文献
8.
I. A. Abdou A. A. Abou-Zeid M. R. El-Sherbeeny Z. H. Abou-El-Gheat 《Plant foods for human nutrition (Dordrecht, Netherlands)》1972,22(1):29-35
The antimicrobial activities of the crude juices ofAllium sativum, Allium cepa, Raphanus sativus have been found to be strongly active onEscherichia coli, Pseudomonas pyocyaneus, Salmonella typhi andBacillus subtilis, while the crude juices ofCapsicum frutenscens andEruca sativa were active only onEscherichia coli, Salmonella typhi andBacillus subtilis. The crude juice ofAllium kurrat was active onEscherichia coli andBacillus subtilis. The active antibacterial substances were easily isolated by different organic solvents.
Zusammenfassung Die antimikrobiellen Aktivitäten der rohen Säfte vonAllium sativum undAllium cepa wurden als stark befunden gegenEscherichia coli, Pseudomonas pyocyaneus, Salmonella typhi undBacillus subtilis, während die rohen Säfte vonCapsicum frutescens undEruca sativa nur gegenEscherichia coli undBacillus subtilis aktiv waren. Der rohe Saft vonAllium kurrat erwies sich als aktiv gegenEscherichia coli undBacillus subtilis. Die aktiven antimikrobiellen Substanzen waren durch verschiedene organische Lösungsmittel leicht zu isolieren.
Résumé Les activités antimicrobiennes des jus crusd'Allium sativum, Allium cepa, Raphanus sativus ont été trouvées actives en affectantEscherichia coli, Pseudomonas pyocyaneus, Salmonella typhi etBacillus subtilis, mais les jus crus deCapsicum frutescens etEruca sativa affectent seulementEscherichia coli, Salmonella typhi etBacillus subtilis. Le jus crud'Allium kurrat affecteEscherichia coli etBacillus subtilis. L'active substance antibactérienne est isolée facilement par dissolvants organiques différents.相似文献
9.
Adel K. Soliman Abdou A.A. El-Horbeety Mohamed A.R. Essa Mohamed A. Kosba Ibrahim A. Kariony 《Aquaculture International》2000,8(4):315-326
Raising ducks on fish ponds (fish-duck culture) on a commercial scale is a new practice in Egypt, therefore, a study was undertaken to evaluate this practice from production, carcass composition and economic viewpoints.Five earthern ponds were used in the non-integrated system (no ducks) whereas four earthen ponds, in which each pond was supplied with 125 Pecking ducks per 0.42 ha, were used for the Integrated system. In both systems, each pond was stocked with four species of fish (common carp Cyprinus carpio, silver carp Hypophthalmichthys molitrix, Grey mullet Mugil cephalus and tilapias Oreochromis niloticusand O. aureus) at the same densities.There were no differences in temperature or pH in any of the ponds but dissolved oxygen levels were lower in integrated ponds concomitant with increasing levels of ammonia, phosphate and nitrate. Water in integrated ponds was richer in natural productivity (phytoplankton and zooplankton) either in species or density when compared with those variables in non-integrated ponds.Fish species reared in integrated ponds exhibited better body weight, food conversion and protein efficiency ratios compared with those of fish species in the non-integrated ponds. Fish yield per 0.42 ha produced from the integrated ponds was significantly higher than that obtained from non-integrated ones. Also, body composition of fish species was affected by the type of farming. Carcass crude protein of grey mullet, silver carp and tilapia was improved in the integrated system. The data on return on sales, return on costs, return on equity, pay-back period and break-even point showed that the integrated system was more profitable than the non-integrated system. 相似文献
10.