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排序方式: 共有213条查询结果,搜索用时 62 毫秒
91.
R Manjarin G Cassar DJ Sprecher RM Friendship JC Dominguez RN Kirkwood 《Reproduction in domestic animals》2009,44(3):411-413
To meet weekly breeding targets, it is occasionally necessary to inject exogenous gonadotrophins to induce oestrus in prepubertal gilts. However, the gilt oestrus response to equine chorionic gonadotrophin (eCG) either alone or in combination with human chorionic gonadotrophin (hCG) can be unpredictable. The objective of the present study was to examine possible reasons for this unpredictability. Prepubertal gilts (90 kg and 153 days of age, n = 109) received an injection of either 600 IU eCG or a combination of 400 IU eCG and 200 IU hCG (PG600), or were non-injected controls, and were then exposed to a mature boar for 15 min daily for 7 days for oestrus detection. At the time of injection, real-time ultrasound revealed that the gilt ovaries had primarily 1–2 mm follicles. Blood samples were obtained at time of hormone injection (day 0) and at days 3, 7 and 10 for assay of serum progesterone concentrations. The oestrus responses by 7 days were15.5%, 73.3% and 0%, for eCG, PG600, and control gilts, respectively (p < 0.001). The oestrus response improved (p < 0.05) with increasing body weight. Based on circulating progesterone levels, all oestrous gilts ovulated except for four of the PG600 gilts. Failure to express oestrus in PG600 gilts was not associated with a premature rise in progesterone. 相似文献
92.
93.
Luciana Lasry Benchimol Tatiana de Campos Sérgio Augusto Morais Carbonell Carlos Augusto Colombo Alisson Fernando Chioratto Eduardo Fernandes Formighieri Lígia Regina Lima Gouvêa Anete Pereira de Souza 《Genetic Resources and Crop Evolution》2007,54(8):1747-1762
A common bean genomic library was constructed using the ‘IAC-UNA’ variety enriched for (CT) and (GT) for microsatellite motifs. From 1,209 sequenced clones, 714 showed microsatellites distributed over 471 simple and 243 compound motifs. GA/CT and GT/CA were the most frequent motifs found among these sequences. A total of 123 microsatellites has been characterized. Out of these, 87 were polymorphic (73.7%), 33 monomorphic (26.8%), and 3 (2.4%) did not amplify at all. In a sample of 20 common bean materials selected from the Agronomic Institute Germplasm Bank, the number of alleles per locus varied 2–9, with an average of 2.82. The polymorphic information content (PIC) of each marker varied from 0.05 to 0.83, with a 0.45 average value. Cluster and principal coordinate analysis of the microsatellite data were consistent with the original assignment of the germplasm accessions into the Andean and Mesoamerican gene pools of common bean. Low polymorphism levels detected could be associated with the domestication process. These microsatellites could be a valuable resource for the bean community because of their use as new markers for genetic studies. 相似文献
94.
Fabiana Aparecida Santilli Brandão Kele Amaral Alves Danielle Cristina Calado de Brito Leda Maria Costa Pereira Glayciane Bezerra de Morais Lucy Vanessa Sulca Ñaupas Samara Silva de Souza Benner Geraldo Alves Ana Paula Ribeiro Rodrigues Dárcio Ítalo Alves Teixeira 《Reproduction in domestic animals》2021,56(8):1156-1161
The present study evaluated the effect of Ovarian Tissue Cryosystem (OTC) on follicular morphology and density, as well as on stromal cell density of vitrified canine ovarian tissue. Canine ovarian fragments collected from adult female dogs in stages of the random oestrous cycle were fixed (FC, fresh control) or vitrified (VIT) with an OTC device. After vitrification and warming, the fragments were fixed for histological analysis. Overall, the mean percentage of normal pre-antral follicles decreased after vitrification procedure (FC: 74.5% ± 1.6% vs. VIT: 52.05% ± 1.5%). Although the rates of normal primordial (71.1% ± 1.8%) and secondary (0.7% ± 0.4%) follicles vitrified showed a reduction (p < .05), vitrification using OTC showed considerable preservation of follicles, when compared to the fresh control (81.1% ± 1.5% and 2.3% ± 0.6%, respectively). The mean follicular density was maintained after vitrification (FC: 199.65 ± 12.8 vs. VIT: 199.68 ± 10.8), whereas the stromal cell density decreased in the VIT group. Based on the results, we recommend the use of OTC for vitrification of canine ovarian tissue. 相似文献
95.
PETR KLEMENT DVM CHRISTOPHER M. FEINDEL MD HUGH E. SCULLY MD EILEEN MESHER RN GIANNOULA KLEMENT BSc PEDRO DEL NIDO MD GREGORY J. WILSON MD 《Veterinary surgery : VS》1987,16(3):231-237
Although techniques for the perioperative management of patients undergoing mitral valve replacement have been well established in humans, the use of these techniques has not been widely accepted in veterinary practice. The purpose of this study is to demonstrate that low morbidity and mortality could be achieved in the dog undergoing mitral valve replacement. Nine mongrel dogs (25-45 kg body weight) were subject to left thoracotomy and mitral valve replacement using cardiopulmonary bypass (CPB). The average time on CPB was 1 hour with an aortic cross-clamping time of 40 minutes using chemically induced cardiac arrest. CPB was performed under conditions of moderate systemic hypothermia (28-30 degrees C) and hemodilution (hematocrit, 25-35%). Operative mortality was 22% (2/9) with one death from excessive bleeding and the other from cerebral air embolism. All other animals recovered and were clinically normal 3 weeks after surgery. The authors conclude that successful mitral valve replacement is possible in the large dog. 相似文献
96.
Vedovatto Marcelo da Silva Pereira Camila Cortada Neto Ibrahim Miranda Moriel Philipe Morais Maria da Graça Franco Gumercindo Loriano 《Tropical animal health and production》2020,52(2):881-886
Tropical Animal Health and Production - The objective of this study was to evaluate the effects of injectable trace minerals (ITM) at the time of weaning on growth, antioxidant, and immune response... 相似文献
97.
Gama Kallidiane Vaneska Mendes Fernandes Pereira Filho José Morais Soares Rafael Farias Cordão Maiza Araújo Cézar Marcílio Fontes Batista Ana Sancha Malveira de Azevedo Silva Aderbal Marcos Madruga Marta Suely Oliveira Ronaldo Lopes Bezerra Leilson Rocha 《Tropical animal health and production》2020,52(2):601-610
Tropical Animal Health and Production - To compare the fatty acid (FA) composition, and chemical and tissue composition of meat, 24 uncastrated males, 12 sheep of the Santa Inês breed, and 12... 相似文献
98.
Monteiro MV Bevilaqua CM Morais SM Machado LK Camurça-Vasconcelos AL Campello CC Ribeiro WL Mesquita Mde A 《Veterinary parasitology》2011,182(2-4):259-263
The aim of this study was to evaluate the anthelmintic activity of hexane (HE), ethyl acetate (EA) and ethanol (EE) extracts obtained from the seeds of Jatropha curcas using the egg hatch inhibition assay (EHA) and the artificial larval exsheathment inhibition assay (LEIA). For the egg hatch assay, HE, EA and EE were used in concentrations of 3.12, 6.25, 12.5, 25 and 50 mg ml(-1), accompanied by a negative control (5% Tween 80) and a positive control (0.025 g ml(-1) thiabendazole). In LEIA, the extracts were tested at a concentration of 1000 μg ml(-1), accompanied by a negative control (PBS). To evaluate the effect of tannins, the extract with the greatest effect was incubated with polyvinyl polypyrrolidone (PVPP). The EE (50 mg ml(-1)) inhibited 99.8% of egg hatching. After the addition of PVPP, the ovicidal effectiveness of EE was reduced to 91.9%. Using the HE and EA, inhibition of egg hatching was 15.3% and 32.2%, respectively. In the LEIA, 18.9% of L3 incubated with EE were exsheathed (p<0.01). The addition of PVPP to EE reversed the inhibitory effect on larval exsheathment. The percentage of exsheathment of L3 incubated with HE (99.6%) and EA (97.8%) did not differ from the control group (p>0.05). The results show that the effects of EE on eggs are not solely due to the tannins. However, these secondary metabolites are implicated in blocking the larval exsheathment. 相似文献
99.
Martins DA Engrola S Morais S Bandarra N Coutinho J Yúfera M Conceição LE 《Fish physiology and biochemistry》2011,37(4):733-743
An experiment was conducted in order to evaluate the effects of feeding frozen Artemia diets differing in arachidonic acid-to-eicosapentaenoic acid ratios (ARA/EPA) on growth, survival and stress coping ability
of Senegalese sole post-larvae (19–31 days after hatch). Two experimental diets presenting high (‘High’; 3.0) or low (‘Low’;
0.7) ARA/EPA ratios were tested under two rearing conditions: undisturbed (C) and stressed by a 2-min air exposure every two
days (S). Growth, survival and basal cortisol levels were similar between groups indicating that independently of dietary
ARA/EPA ratios, fish were able to cope with the repeated stress imposed. Also, cortisol levels at 3 h past air exposure were
determined in all groups at the end of the experiment. Among fish fed the ‘Low’ diet, C groups seemed to present a quicker
recovery from the acute stress (basal-like levels) than S groups. Repeated stress effects were not apparent in fish fed the
‘High’ diet and, relative to basal levels, twofold higher cortisol concentrations were detected at 3 h, in both C and S groups.
This study suggests the importance of ARA in steroidogenesis regulation and the modulatory role of EPA in this process. Despite
the tolerance to a wide range of dietary ARA/EPA as indicated by growth and survival results, acute stress coping response
may be more efficient in Senegalese sole post-larvae fed low ARA/EPA ratios and, under these particular conditions, a faster
recovery of cortisol to basal values could be indicative of rearing conditions (undisturbed vs. repeatedly stressed). 相似文献
100.
AIM: Using specified indices, to determine the nutritional and thermal status of calves between 1 and 4 days of age. METHODS: After birth, calves (n=106) were collected daily, according to farm practice. Over the following 4 days a jugular blood sample and rectal temperature were taken twice daily before feeding. Plasma concentrations of glucose, beta-hydroxybutyrate and urea, and gamma-glutamyl transferase (GGT) activities were determined. The significance of differences in plasma composition and rectal temperature between calves whose birth had been assisted or unassisted, and between calves with low and high plasma GGT activities 24 h after birth, was determined using repeated measures analysis of varianc RESULTS: There were no marked differences in plasma metabolite levels or body temperature of assisted and unassisted calves. Calves that had high plasma GGT activities 24 h after birth had higher plasma glucose concentrations over the 4 days than calves that had low plasma GGT activities (p<0.001). Overall, compared to published data on poorly-fed and hypothermic calves, calves in this study were normoglycaemic, their plasma beta-hydroxybutyrate and urea concentrations were low and their rectal temperatures were normal, indicating that they were well fed and did not become hypothermic. CONCLUSIONS: The nutritional and thermal status of at least 90% of the calves was compatible with good health and survival during the first 4 days after birth. 相似文献