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71.
A 5-year-old female cat with nonregenerative anemia and thrombocytopenia was diagnosed with myelodysplastic syndromes (MDS), since peripheral blood and bone marrow (BM) examination revealed various dysplasias and a blast ratio of 19%. Chemotherapy with azacytidine (AZA; 70–35 mg/m2, 3–5 days, three cycles) and treatment with prednisolone, antibiotics, and vitamin K2, and blood transfusion were performed. On day 106, blast cells and dysplasia had decreased in the BM, and the cat remained alive for at least 1,474 days. This report is the first on feline MDS treated with AZA, suggesting appropriate drug dosage, interval and effective combination should be investigated and the pharmacological and cell biological mechanisms needs to be elucidated in the future.  相似文献   
72.
A male Holstein-Friesian calf was born with multiple, cauliflower-like, pale pink cutaneous masses on the head and limbs. On histopathological examination, the cutaneous masses were diagnosed as congenital cutaneous fibropapillomatosis. Those lesions involved focal proliferation of sebaceous gland in the dermis. There were no histological findings to suggest bovine papillomavirus infection, such as the presence of intranuclear inclusion bodies, large keratohyalin granules, and koilocytosis. Furthermore, papillomaviral antigens and DNA were not detected by immunohistochemistry and polymerase chain reaction, respectively. These results suggested that there was no association between these cutaneous lesions and bovine papillomavirus infection, and the lesions were considered as harmartomatous changes.  相似文献   
73.
A variety of investigations into alternative systems and furnished cages for laying hens have been conducted, mainly in the European Union. However, comparative studies about the behavior of laying hens just after introduction to these housing systems are few. Therefore, this study aimed to investigate the changes of location and behavior of laying hens just after introduction to three housing systems. In total, 181 White Leghorns were used. Thirty‐six birds were allocated to 12 battery cages with three birds per cage (613 cm2/bird); 36 birds were allocated to nine furnished cages with four birds per cage (1170 cm2/bird); and 109 birds were allocated to an aviary (1130 cm2/bird). Direct observations using scanning techniques were conducted over 2 weeks for 4 h/day from the day following the introduction. Scan samples of location and behavior were taken at 10 min intervals. The proportion of birds that stayed at each location in the furnished cages was stable during the observation period. In the aviary, 78% of birds were observed on the floor on the first day, and thereafter the proportion linearly decreased (P < 0.01). The proportions of birds eating in both the battery and furnished cages were stable, indicating that the caged birds would adjust to these environments within a short period. Display of aggression was lower in both the cages (both 0.3 ± 0.1%) than in the aviary (3.5 ± 1.0%, P < 0.001), which indicates the early establishment of social order in both cage systems. In the aviary, the birds were observed eating less frequently than in both the cages on the first day, and the proportion thereafter linearly increased (P < 0.01), and the use of tiered wire floors with feeders accompanied this (P < 0.01). Comfort behaviors, including dust bathing, were noted less in the aviary than in the furnished cages throughout the observation period (both P < 0.05). These results suggest that adjustment of aviary birds to their new environment had been delayed compared with caged birds because of the prerearing conditions and the environmental complexity of the aviary.  相似文献   
74.
To evaluate the effects of environmental enrichment on behavioral, physiological and productive characteristics, 71 Japanese Black × Holstein steers (8 months of age; 299.5 ± 22.6 kg) were allocated to three pens in two repetitive experiments. Pen C (n = 11 and 12) consisted of a feeding alley for grain feed, a trough for dry hay, a water bowl and a resting space as a control pen. Pen D (n = 12 and 12) included a drum can (58 cm diameter × 90 cm height) containing hay. Pen GD (n = 12 and 12) included a drum can that was placed around artificial plastic turf (30 × 120 cm) for grooming. The drum cans were removed after 5 months of installation. Behavioral observations were made for 2 h at 10 min intervals after feeding on three successive days each month for 10 months. Agonistic interactions were also continuously observed for 1 h after feeding to assess the dominance order (DO). Sampling blood and measuring bodyweight were performed bimonthly. The steers used the drum can frequently for 3 months after installation (1st, 2nd, 3rd months vs 4 months, all P < 0.05). The frequency of total eating of grain feed and hay was higher in pen D and pen GD than in pen C (both P < 0.01), while it was lowest in pen GD after removal of the drum can (P < 0.05). Grooming at the drum can was observed more frequently in pen GD than in pen D (P < 0.05). After they finished eating the grain feed, they ate hay at the drum can that contained additional hay rather than at the trough for hay (P < 0.01). Plasma dopamine concentrations were higher in pen D than in pen C (P < 0.05), and serum triglyceride concentrations were higher in pen C than in pen GD (P < 0.05) during the installation of the drum can. After removal of the drum can, serum total cholesterol concentrations became higher in pen D and GD than in pen C (both P < 0.05). Average daily gain correlated positively with the frequency of eating hay at the drum can in pen D (rs = 0.52, P < 0.01). In pen GD, the frequency of using the drum can correlated negatively with DO (rs = ?0.59, P < 0.01). Carcass belly fat was thicker in pens D and GD than in pen C (both P < 0.01). In pen GD, the frequency of eating hay (rs = 0.79, P < 0.01) and grooming at the drum can (rs = 0.63, P < 0.05) correlated positively with the marbling score. Although social factor affected the steers using the drum can, installing it in the early fattening stage encouraged the steers to eat and groom there and resulted in better carcass characteristics through the prolonged physiological positive effects.  相似文献   
75.
To provide useful information on how to moderate post‐handling stress, Angus heifers (n = 157) were individually allowed to enter a choice area after 2 min of restraint in a crush and to choose between two pens. After the animal had chosen a pen, free access was given to both test pens and the choice area for a further 5 min. The behaviors during choice and after the first choosing were observed. In experiment 1, each heifer was given one of the following choices: pen with three familiar heifers (peers) versus pen with six sheep (sheep; n = 30); peers versus the bare pen (bare; n = 30); sheep versus bare (n = 30). When the choice combination was peers versus bare, more heifers than expected by chance chose the peers pen (χ2 = 4.80; P < 0.05). However, when one of the other choice combinations was given, there was no significant difference between the number choosing a pen and the expected value. After the first choice, more heifers entered the peers pen than the bare pen (P < 0.05) or the sheep pen (P < 0.10). In experiment 2, another 67 heifers were given one of the following choices: peers versus pen with a novel object (NO; n = 19); sheep versus NO (n = 22); bare versus NO (n = 26). There was no significant difference between the number of heifers choosing a pen and the expected value in any choice combination. However, more heifers entered the peers pen than the NO pen (P < 0.01). It is concluded that sheep were not as attractive as peers, but sheep were not fearful animals for cattle.  相似文献   
76.
Endogenous relationship to restraint and human handling were studied with growing–fattening steers. Thirty‐five crossbred (Japanese Black × Holstein) steers aged 6–10 months were randomly assigned to three pens. They had free access to an Italian ryegrass hay and a restricted amount of high‐concentrate diets (total digestible nutrients (TDN) 70.5%, digestible crude protein (DCP) 10.0%) for the first 6 months of trial. Then they had free access to an oat hay and another vitamin A‐restricted diet (TDN 72.0%, DCP 10.0%) until slaughter. The steers were individually driven into a restraint stall, and bodyweight was recorded. Blood samples were then collected under haltered conditions. These serial handling procedures started at 2 h after the morning feeding were conducted in months 1, 3, 5 (growing stage, GS) and in months 7, 9, 11 (fattening stage, FS) of the trial. Mean peripheral blood concentrations of epinephrine (A; GS, 117.4 ± 76.4 pg/mL; FS, 64.1 ± 34.2 pg/mL), norepinephrine (NA; GS, 257.7 ± 95.0 pg/mL; FS, 125.9 ± 44.1 pg/mL), cortisol (GS, 1.6 ± 0.8 µg/dL; FS, 1.2 ± 0.4 µg/dL), glucose (GS, 83.1 ± 7.5 mg/dL; FS, 71.9 ± 6.9 mg/dL), non‐esterified fatty acid (NEFA; GS, 0.13 ± 0.06 mEQ/L; FS, 0.10 ± 0.06 mEQ/L) and vitamin A (GS, 90.5 ± 24.6 IU/dL; FS, 37.2 ± 21.3 IU/dL) were higher (all P < 0.01) in the GS than in the FS, whereas those of insulin (GS, 1.06 ± 0.82 µU/mL; FS, 1.36 ± 0.61 µU/mL) and leptin (GS, 4.5 ± 1.8 ng/mL human equivalent (HE); FS, 6.8 ± 2.4 ng/mL HE) were lower (both P < 0.01). The metabolite that correlated with A and NA was glucose (A: r = 0.61, P < 0.001; NA: r = 0.53, P < 0.01) in the GS, and the metabolites correlating with A, NA and cortisol were NEFA (A: r = 0.31, P < 0.10; NA: r = 0.32, P < 0.10; cortisol: r = 0.41, P < 0.05) and triglyceride (A: r = ?0.37, P < 0.05; NA: r = ?0.39, P < 0.05) in the FS. Vitamin A was a mediator between A (r = ?0.38, P < 0.05) and NA (r = ?0.42, P < 0.05) and insulin (r = 0.31, P < 0.10) in the GS, and between NA (r = ?0.33, P < 0.10) and leptin (r = 0.38, P < 0.05) in the FS. In conclusion, when changing from the growing to the fattening stages, the stress of handling and restraint had caused the pathways to shift from carbohydrate metabolism to lipid metabolism. In addition, vitamin A seemed to be an important mediator in the endogenous pathways in both stages.  相似文献   
77.
This study aimed to investigate the effects of decreased light intensity and beak trimming on aggression prevention in laying hens. In total, 181 White Leghorns were used. At 17 weeks of age, 36 birds were allocated to battery cages (three birds/cage), 36 birds to furnished cages (four birds/cage), and 109 birds were transferred to an aviary. Since aggression increased in the birds from 23 weeks of age (from 0.3% to 6.0%) especially in the furnished cages, , the light intensity during the daytime was decreased to about one‐tenth (from 680 lux to 70 lux) at 28 weeks of age. The birds in the furnished cages then had their beaks re‐trimmed lightly by using a debeaker at 29 weeks of age. Behavioral observations using scanning techniques at 10 min intervals were conducted. Feed intake, bodyweight and feather score were also measured. There was no significant difference in aggression before and after decreasing the light in all three housing systems. On the other hand, the proportion of birds showing aggression decreased significantly just after trimming and four weeks after beak trimming in the furnished cages (P < 0.05 and P < 0.01, respectively). The aggression also became similar to the proportions observed in the battery cages and in the aviary. In proportion to the decreased aggression, the proportion of birds eating significantly decreased (P < 0.05). However, their feed intake and bodyweight did not decrease significantly. Against this decreased aggression, the proportion of birds preening significantly increased (P < 0.05). Aggression was observed more frequently at the dust bath in the furnished cages and at the litter floor in the aviary (both P < 0.001). The total feather score for all body parts in the birds in furnished cages increased significantly (P < 0.01) from 25 to 29 weeks of age (at beak trimming), but did not increase significantly from 29 to 33 weeks of age. The increments of neck, breast and tail feather scores in the furnished cages were smaller. In conclusion, there was no significant difference in aggression between just before and after decreasing the light in any housing system. However, aggression in the furnished cages was reduced not only by decreasing the light intensity, but by additional beak trimming. Aggravation of feather conditions – especially at the neck, breast and back – was prevented by the treatment.  相似文献   
78.
The antiradical function of sulfhydryl (SH) residue in dairy cattle plasma and the relationship of SH residue concentrations to other oxidative stress markers, ascorbic acid and thiobarbituric acid reactive substance (TBARS) in plasma were investigated. The concentration of reduced glutathione (GSH) in phosphate buffer solution (pH 7.6) and SH residues in dairy cattle plasma decreased significantly (P < 0.05) in vitro by the addition of peroxyradicals at 38°C, depending on incubation periods. The decrease of GSH concentration with the peroxyradical solution was partially protected by the addition of sodium ascorbate solution. A positive and significant correlation with SH residues and albumin concentration in the fresh plasma obtained from 15 dairy cattle was observed (P < 0.05). The SH residue concentration was not correlated with the TBARS concentration in plasma. The total ascorbic acid and SH residues concentration in the plasma correlated positively but not significantly (P < 0.10). These results suggested that SH residues in dairy cattle plasma play important part in the antiradical function.  相似文献   
79.
中性松香施胶剂的制备及施胶特性   总被引:6,自引:1,他引:5  
本研究制备了多种烃基松香酯-松香施胶剂及松香甘油酯-松香施胶剂,并对其在中、碱性造纸施胶中的应用进行了探讨。施胶结果表明,松香甘油酯-松香施胶剂能有效地用于中、碱性施胶,然而其它烃基松香酯-松香施胶剂在同样条件下却无施胶效果。这意味着中性松香胶施胶剂的制备及性能并非完全取决于松香羧基的改性而是松香酯的结构有关。虽然碱性填料碳酸钙的添加引起一定程度的施胶效果的下降,松香甘油酯-松香中性施胶剂在含有碳  相似文献   
80.
In 1998, rhus (Rhus javanica L.) yellows (RhY), caused by phytoplasma, was found in Miyagi Prefecture, Japan. In vector transmission tests, Hishimonus sellatus acquired RhY phytoplasma from diseased R. javanica and transmitted it to healthy R. javanica. Twenty-two species of herbaceous plants in 10 families were infected with RhY phytoplasma by H. sellatus. The host range and main symptoms on test plants of RhY phytoplasma differed from those of Macrosteles striifrons-transmitted phytoplasmas, which belong to the same 16Sr I group phytoplasma. Received 6 December 1999/ Accepted in revised form 14 May 2000  相似文献   
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