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51.
52.
The leaf essential oils (six samples) from three clones of Eucalyptus camaldulensis Dehnh. were characterized by gas chromatography-mass spectrometry. Radical scavenging and antioxidant properties were investigated by the 1,1-diphenyl-2-picylhydrazyl (DPPH) assay and the β-carotene bleaching test. It was found that the whole essential oil and its fractions had significant antioxidant effects when they were tested by each method. In the DPPH assay, the E. camaldulensis leaf oils showed IC50 inhibitory concentrations in the range of 1.75–12.62 mg/ml. In the β-carotene bleaching test, the IC50 valued were in the range of 14.30–118.55 μg/ml. Part of this report was presented at the 18th meeting of the Chugoku-Shikoku Branch of the Japan Wood Research Society, November 2006  相似文献   
53.
Sulfate-reducing bacteria, widely distributed in natural environments, have a specific ability to reduce sulfate and to form hydrogen sulfide, which reacts with iron or/and manganese present in the environments and forms a black precipitate of iron or/and manganese sulfide. This specific reaction is useful for the simple and selective detection of sulfate-reducing bacteria in mixed bacterial populations as in soil.  相似文献   
54.
Two 2-month-old kittens presented with a loud cardiac murmur. One cat showed severe signs of heart failure such as respiratory effort and exercise intolerance. Echocardiography revealed left ventricular concentric hypertrophy and severe left ventricular outflow obstruction. They died at 5 and 12 months of age, respectively. Necropsy and histopathology confirmed hypertrophic cardiomyopathy.  相似文献   
55.
Forest‐grazing enables the intake of high total antioxidant capacity (TAC) plants that might be beneficial for the TAC status of cattle. This study evaluated the relation between the seasonal foraging patterns of forest‐grazing Japanese Black (JB) heifers or the TAC levels in shrubs and trees and the changes of plasma TAC. We examined 12 JB heifers, four each of which were allocated to forest‐grazing (F), pasture‐grazing, and pen‐housed groups. The plasma TAC level in F heifers on July 26, August 13, 30 and September 17 were significantly higher than those on April 27 and June 4 (P < 0.05). In F group, the mean rates of foraging frequency (FF) of shrubs and trees during July 5–8 and September 13–16 were much higher than that during May 31–June 3 (P < 0.05). The rate of FF of grass significantly decreased later in the season (P < 0.05). The mean TAC levels in these shrubs and trees were higher than those in grasses, concentrates, and timothy hay. Results suggest that an important factor in the increase of plasma TAC in forest‐grazing cattle might be the increased foraging of TAC‐rich shrubs and trees during summer–fall.  相似文献   
56.
Antimicrobial therapy is a useful tool to control bovine mastitis caused by Staphylococcus aureus, as consequence an increase in staphylococci resistant cases has been registered. Alternative strategies are desirable and bacteriocins represent attractive control agents to prevent bovine mastitis. The aim of this work was to evaluate the activity of five bacteriocins synthesized by Bacillus thuringiensis against S. aureus isolates associated to bovine mastitis. Fifty S. aureus isolates were recovered from milk composite samples of 26 Holstein lactating cows from one herd during September 2007 to February 2008 in México and susceptibility of those isolates to 12 antibiotics and 5 bacteriocins from B. thuringiensis was evaluated. S. aureus isolates were mainly resistant to penicillin (92%), dicloxacillin (86%), ampicillin (74%) and erythromycin (74%); whereas susceptibility to gentamicin, trimethoprim and tetracycline was detected at, respectively, 92%, 88%, and 72%. All S. aureus isolates showed susceptibility to the five bacteriocins synthesized by B. thuringiensis, mainly to morricin 269 and kurstacin 287 followed by kenyacin 404, entomocin 420 and tolworthcin 524. Our results showed that S. aureus isolates had differences in the antimicrobial resistance patterns and were susceptible to bacteriocins produced by B. thuringiensis, which could be useful as an alternative method to control bovine mastitis.  相似文献   
57.
  • 1. The change in fish fauna was monitored in ponds within irrigation systems in Iwate prefecture, north‐eastern Japan to evaluate the effectiveness of eradicating the invasive piscivorous largemouth bass, Micropterus salmoides.
  • 2. Eleven study ponds were categorized into three pond groups: bass‐dwelling (n=3), bass‐eradicated (n=3) and non‐invaded ponds (n=5).
  • 3. Species richness and diversity, which temporally decreased in bass‐dwelling ponds, increased in bass‐eradicated ponds. Furthermore, in bass‐eradicated ponds, the mean numbers of topmouth minnow and freshwater goby were gradually restored, but in bass‐dwelling ponds the numbers decreased and both species eventually disappeared.
  • 4. Although the eradication of piscivorous invaders is helpful for restoring fish species diversity in ponds, its effectiveness varies among species, and other alien fish such as the rose bitterling (Rhodeus ocellatus ocellatus) often invade and proliferate in the bass‐eradicated ponds.
  • 5. To ensure successful restoration of native biota and avoid undesirable results, it is necessary to plan and implement continuous monitoring and adaptive management after eradication of alien predators. Copyright © 2010 John Wiley & Sons, Ltd.
  相似文献   
58.
The water‐holding capacity (WHC), and toughness (shear force) of chicken gizzard were evaluated during postmortem storage for 4.5, 7, 12, 24, 48, 72 and 96 h at 4°C. Degradation of the cytoskeletal proteins desmin, talin and vinculin were monitored by sodium dodecyl sulfate – polyacrylamide gel electrophoresis and Western blotting during the same designated storage period. The WHC of the gizzards decreased significantly from 12 h to 72 h of storage, but by 96 h the WHC was restored to the level measured after storage for 12 h. The shear force value of the gizzards increased rapidly until 12 h and then decreased until 24 h, with a further slight decrease by 48 h. Degradation products of desmin, talin and vinculin appeared at 96 h, 12 h and 48 h postmortem, respectively. The intensity of immunolabeling for desmin, talin and vinculin after storage for 96 h decreased to 51%, 25% and 52% of the initial value. The appearance of desmin degradation products was accompanied by an increase in WHC. This suggests that the postmortem degradation of desmin is involved in the increase of WHC in chicken gizzard during storage at 4°C, and talin and vinculin may be involved.  相似文献   
59.
It was reported in previous papers (1, 2) that suifate-reducing bacteria were not uniformly distributed throughout a paddy-field soil. They appeared to grow in small contiguous clumps scattered throughout the soil and this suggests the heterogeneous distribution of minute loci with different growth conditions for sulfate-reducmg bacteria in the soil; i.e., the scattering of organic matter, the association of other microorganisms, the availability of soil water and air, the oxidation-reduction potential and so on. In marine sediments, the distribution and activity of suifate-reducing bactena were reported to be influenced mainly by organic matter therein (3). In a paddy-field soil, we have often observed that organic matter, such as plant debns and rotted roots, was present in the center of the dark black soil mass. In the experiment desenbed m this paper, an attempt was made to elucidate the influence of organic matter on the distribution pattern of suifate-reducing bacteria in the soil.  相似文献   
60.
In October 2007, a 15-year-old Japanese Black cow on Ishigaki Island, Okinawa, Japan, was diagnosed with Anaplasma marginale infection based on clinical symptoms, blood examination, smear observation, 16S rRNA and groEL gene sequence analysis, and the result of a CF test. The cow was introduced into the farm from mainland Japan as a calf in 1993, one year before the eradication of Rhipicephalus (Boophilus) microplus, the main vector of A. marginale in Okinawa Prefecture. It is possible that the cow was first infected with A. marginale as a calf in Ishigaki Island and had been persistently infected since then. This is the first reported clinical case of A. marginale infection of cattle since the eradication of R. microplus in Okinawa Prefecture. Additional analysis of major surface protein 1α amino acid sequences revealed that the A. marginale Okinawa strain presented four new repeat forms which were not seen in other strains. This indicates that the Okinawa strain may be a unique geographical variant of A. marginale.  相似文献   
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