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201.
EOS Batista GG Macedo RV Sala MDDV Ortolan MF Sá Filho TA Del Valle EF Jesus RNVR Lopes FP Rennó PS Baruselli 《Reproduction in domestic animals》2014,49(3):448-452
In Bos taurus cattle, antimullerian hormone (AMH) has been demonstrated to have a high degree of correlation with ovarian antral follicle count and the number of healthy follicles and oocytes. To document the correlation between the plasma concentration of AMH and follicular number in Bos indicus and Bos taurus heifers, Nelore (Bos indicus, n = 16) and Holstein heifers (Bos taurus, n = 16) had their ovarian follicular waves synchronized. After synchronization, ovarian antral follicular population (AFP) was evaluated three times at 60‐day (d) intervals (T‐120 d, 120 days before plasma AMH determination; T‐60 d, 60 days before; and T0, at the time of plasma AMH determination). The plasma AMH concentration was positively correlated with the number of ovarian follicles on the day of the follicular wave emergence in Bos indicus (Nelore) and Bos taurus (Holstein) heifers at each evaluation time (p < 0.05). The AFP was higher in Bos indicus (Nelore) than in Bos taurus (Holstein) heifers (p < 0.05). Similarly, the AMH concentration was higher in Bos indicus (Nelore) than in Bos taurus (Holstein) heifers (p < 0.0001). When heifers were classified as to present high or low AFP according to the mean of the AFP within each genetic group, high‐AFP heifers presented a greater (p < 0.0001) AMH concentration than low‐AFP heifers, regardless of the genetic group. In conclusion, the AFP is positively correlated with plasma AMH concentration in both Bos indicus (Nelore) and Bos taurus (Holstein) heifers. Furthermore, Bos indicus (Nelore) heifers presented both greater plasma AMH concentrations and AFP than Bos taurus (Holstein) heifers. 相似文献
202.
F Gonzalez J Sulon Jm Garbayo M Batista F Cabrera Po Calero A Gracia Jf Beckers 《Reproduction in domestic animals》2000,35(2):79-82
Plasma concentrations of pregnancy‐associated glycoproteins (PAG) were determined in goats during pregnancy by two homologous radioimmunoassays that employed caprine PAG55+62 (caPAG55+62) and caprine PAG55+59 (caPAG55+59) and their specific antisera. The effects of fetal number on PAG concentrations were analysed. The concentrations of caPAG55+62 were higher than that of caPAG55+59 throughout pregnancy (p <0.05). Both caPAG55+62 and caPAG55+59 reached maximal levels in week 8 (48.6 ± 5.0 and 30.4 ± 4.3 ng/ml, respectively), decreased between weeks 12 and 14 (45.5 ± 2.5 to 31.9 ± 2.7 ng/ml and 30.6 ± 2.1 to 15.8 ± 2.8 ng/ml, respectively, p <0.01) and remained relatively constant until parturition. Twin‐bearing goats had higher PAG concentrations than single‐bearing animals, but the difference was only significant in week 4 (52.3 ± 3.7 versus 30.9 ± 3.9 ng/ml and 18.9 ± 1.7 versus 12.6 ± 2.0 ng/ml, for caPAG55+62 and caPAG55+59, respectively, p <.,0.05). This is the first study of PAG concentrations in goat throughout pregnancy by a homologous radioimmunoassay system. The profiles of caPAG55+62 and caPAG55+59 were closely parallel. Concentrations of PAG were lower than those obtained by a heterologous radioimmunoassay and their patterns were also different, due to a different specificity of the antisera used in heterologous system. Goats that delivered twins had higher PAG concentrations at the time of implantation than those that delivered a single fetus, indicating that PAG concentrations provide a useful measure of the trophoblast secretory activity. 相似文献
203.
Luiz F Dias Batista Aaron B Norris Jordan M Adams Thomas B Hairgrove Luis O Tedeschi 《Journal of animal science》2021,99(10)
Rumen acidosis is a common metabolic disorder occurring when organic acid production exceeds clearance capacity, reducing ruminal pH. The occurrence of acidosis has been directly correlated to the ratio of concentrate to forage in the diet. However, rates of substrate fermentation and acid absorption vary at different locations in the reticulo-rumen. The objective of this study was to determine the pH and redox potential (Eh) in different locations of the reticulo-rumen using 16 ruminally cannulated steers (309 ± 43 kg) receiving different supplementation levels of quebracho extract (QT; Schinopsis balansae) within a grower type diet (CP: 13.4%; total digestible nutrients [TDN]: 70.4%; and ME: 2.55 Mcal/kg, dry matter [DM] basis). Animals were randomly assigned to one of four dietary treatments: QT at 0%, 1%, 2%, and 3% of DM (QT0, QT1, QT2, and QT3, respectively), containing about 0%, 0.7%, 1.4%, and 2.1% of condensed tannins (CT), DM basis, respectively. Animals were adapted to the basal diet for 12 d before being introduced to predetermined treatments for 4 weeks (wk), with diets provided twice daily to allow ad libitum intake. Weekly measurements of ruminal fluid pH and Eh were taken 4 h post-feeding using a portable pH meter with two probes (pH and redox) in four locations of the reticulo-rumen (reticulum, cranial sac, dorsal sac, and ventral sac). Data were analyzed using a random coefficients model with the pen as a random effect and wk as repeated measures, with DM intake included as a covariate. There was no interaction among treatments, location, and wk (P ≥ 0.882) on reticulo-ruminal pH. Overall, ruminal pH was lower for QT0 and QT1 compared to QT3 (P < 0.001). The pH in the reticulum was greater than those of the ventral and dorsal sacs (6.05 vs. 5.94, 5.89, respectively; P ≤ 0.001) but similar to cranial sac (6.00). Reticular pH was positively correlated with the ruminal locations (≥0.78; P < 0.001). The linear equation to estimate ruminal mean pH using reticulum pH had an intercept and slope different from zero (P ≤ 0.04), but CT (% DM) was not different from zero (P = 0.15), root mean square error of 0.15, and R2 of 0.778: 0.723 (±0.36) + 0.857 (±0.059) × reticulum pH + 0.033 (±0.023) × CT. The Eh was lower for QT0 in week 1 than all other treatments (P < 0.001). We concluded that reticulo-ruminal pH differs among locations in the rumen regardless of QT supplementation level and days on feed, with reticular pH being the highest. 相似文献
204.
de Souza Farias Jos Williano Orella Jonathan Said Tejeda dos Santos Batista Edgar Cordeiro Rafael Cruz Passos Adriana Rodrigues Silva Luiz Cludio Costa 《Genetic Resources and Crop Evolution》2022,69(3):1365-1374
Genetic Resources and Crop Evolution - Physalis angulata L. is an American species with edible fruits that stands out for having high nutritional and pharmaceutical value. The species is found in... 相似文献