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31.
Objective – To compare the incidence of seizures in dogs with intervertebral disk disease after iopamidol or iomeprol myelography, and to assess whether the incidence of seizures differed between the 2 agents when severity of neurological deficits, location of cord compression, duration of anesthesia, site of myelogram, volume of contrast, and concentration of contrast were evaluated. Design – Retrospective study. Setting – Veterinary teaching hospital. Animals – One hundred and sixty‐one client‐owned dogs with intervertebral disk disease. Interventions – Subarachnoid injection of contrast medium. Measurements and Main Results – One hundred and sixty‐one dogs with intervertebral disk disease were subjected to myelography using iopamidol (n=74) or iomeprol (n=87). Cranial myelography was performed in 31 dogs, caudal myelography in 125 and both cranial and caudal myelography in 5. Seizures occurred in 23 of 161 (14%) dogs. There was no significant difference overall between iopamidol and iomeprol myelography. However, in dogs with thoracolumbar disk extrusion and paraplegia, seizures occurred more frequently after caudal myelography using iopamidol compared with iomeprol. Conclusions – Both iomeprol and iopamidol are suitable for myelography in dogs. Iomeprol is recommended for caudal myelography in paraplegic dogs with thoracolumbar disk extrusion due to the higher incidence of seizures in this group when iopamidol was used.  相似文献   
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Two experiments were conducted to determine the efficacy of mannan oligosaccharides (MOS) fed at two levels of Cu on growth and feed efficiency of weanling and growing-finishing pigs, as well as the effect on the immunocompetence of weanling pigs. In Exp. 1, 216 barrows (6 kg of BW and 18 d of age) were penned in groups of six (9 pens/treatment). Dietary treatments were arranged as a 2 x 2 factorial consisting of two levels of Cu (basal level or 175 ppm supplemental Cu) with and without MOS (0.2%). Diets were fed from d 0 to 38 after weaning. Blood samples were obtained to determine lymphocyte proliferation in vitro. From d 0 to 10, ADG, ADFI, and gain:feed (G:F) increased when MOS was added to diets containing the basal level of Cu, but decreased when MOS was added to diets containing 175 ppm supplemental Cu (interaction, P < 0.01, P < 0.10, and P < 0.05, respectively). Pigs fed diets containing 175 ppm Cu from d 10 to 24 and d 24 to 38 had greater (P < 0.05) ADG and ADFI than those fed the basal level of Cu regardless of MOS addition. Pigs fed diets containing MOS from d 24 to 38 had greater ADG (P < 0.05) and G:F (P < 0.10) than those fed diets devoid of MOS. Lymphocyte proliferation was not altered by dietary treatment. In Exp. 2, 144 pigs were divided into six pigs/pen (six pens/treatment). Dietary treatments were fed throughout the starter (20 to 32 kg BW), grower (32 to 68 kg BW), and finisher (68 to 106 kg BW) phases. Diets consisted of two levels of Cu (basal level or basal diet + 175 ppm in starter and grower diets and 125 ppm in finisher diets) with and without MOS (0.2% in starter, 0.1% in grower, and 0.05% in finisher). Pigs fed supplemental Cu had greater (P < 0.05) ADG and G:F during the starter and grower phases compared to pigs fed the basal level of Cu. During the finisher phase, ADG increased when pigs were fed MOS in diets containing the basal level of Cu, but decreased when MOS was added to diets supplemented with 125 ppm Cu (interaction, P < 0.05). Results from this study indicate the response of weanling pigs fed MOS in phase 1 varied with level of dietary Cu. However, in phase 2 and phase 3, diets containing either MOS or 175 ppm Cu resulted in improved performance. Pharmacological Cu addition improved gain and efficiency during the starter and grower phases in growing-finishing pigs, while ADG response to the addition of MOS during the finisher phase seems to be dependent upon the level of Cu supplementation.  相似文献   
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Objectives To determine the patterns of work undertaken by veterinarians during the first 5 years after graduation, and to study the background to career decisions. Design Longitudinal study. Population Veterinarians (119) who started the veterinary course at The University of Queensland in 1985 and 1986, and who responded to a mailed questionnaire 5 years after they graduated. Procedure Questionnaires were completed in the first and fifth year of the veterinary course, and in the second and after the fifth year after graduation. The data were coded numerically and analysed using the SAS System for Windows. Results Most respondents (61%) planned to work in mixed practice and 61% entered mixed practice initially, but only 39% of these (26% of the total) remained in mixed practice after 5 years. Those who had grown up on a farm which derived primary income from animals were more likely to enter mixed practice, but half of this group had left mixed practice after 5 years. Most decisions to change career direction involved a move away from negative factors including inadequate private time and/or rewards, issues involving other people including the practice principal and sometimes clients, or aspects of the work itself. However, some cited positive reasons, including opportunities to learn, to help others or to travel. There were no significant differences between males and females in the numbers entering mixed practice or leaving it, or entering small animal practice, or in attitudes to many issues involving veterinarians. However, more females than males found their remuneration too small, and females did receive significantly smaller incomes than males. Conclusions Most graduating veterinarians, especially those from farms with animals, seek to enter mixed practice initially. Negative experiences are mainly responsible for moves to small animal practice. Gender does not affect the distribution of young veterinarians between mixed and small animal practice.  相似文献   
34.
Tumor ascites fluids from guinea pigs, hamsters, and mice contain activity that rapidly increases microvascular permeability. Similar activity is also secreted by these tumor cells and a variety of other tumor cell lines in vitro. The permeability-increasing activity purified from either the culture medium or ascites fluid of one tumor, the guinea pig line 10 hepatocarcinoma, is a 34,000- to 42,000-dalton protein distinct from other known permeability factors.  相似文献   
35.
Biological characterisation of Australian isolates of chicken anaemia agent   总被引:1,自引:0,他引:1  
Three Australian isolates of chicken anaemia agent (CAA) resisted treatment at 70 degrees C for 5 min and chloroform treatment. Although minor antigenic differences were detected using monoclonal antibodies to CAA, the Australian isolates were indistinguishable from the reference Cux-1 and Gifu-1 isolates in cross-immunofluorescence and cross-neutralisation tests employing polyclonal chicken antiserums. The Australian viruses were pathogenic for intramuscularly inoculated 1-day-old SPF chicks, but were less pathogenic for 7-day-old chicks. Thus the Australian isolates of CAA did not differ significantly in these properties from previously characterised CAA isolates from other continents.  相似文献   
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Hodge  G.R.  Dvorak  W.S. 《New Forests》2000,19(3):241-258
Seedlings from a wide array of 23 species, varieties,and geographic races were screened for resistance topitch canker using artificial inoculation in agreenhouse. Seed to represent these taxa weregenerally collected in natural stands. In addition,seedlings from 79 families of P. radiata fromcommercial populations from Chile and New Zealand werescreened in a separate experiment. There was littlevariation in resistance among the commercial P.radiata families, with over 98% mortality. Similarresults were obtained with native P. radiatapopulations. All close relatives of P. radiata(sub-section Patula) were very susceptible. However,a number of closed-cone pine species (specifically,from sub-section Oocarpa) were generally veryresistant, with survival approaching 100%. Inaddition, in P. oocarpa, P. jaliscana, and P. tecunumanii from low elevation provenances anextremely high frequency of trees suffered no apparentdamage from the pathogen (92%, 85% and 80%,respectively).  相似文献   
38.
Regulation of extravascular coagulation by microvascular permeability   总被引:18,自引:0,他引:18  
Extravascular coagulation is a prominent feature of such important pathological processes as cellular immunity and neoplasia and has been thought to result from procoagulants associated with the inflammatory or tumor cells peculiar to these entities. It was found that increased microvascular permeability alone is sufficient to induce equivalent extravascular coagulation in several normal tissues. The results indicate that saturating levels of procoagulant are present even in normal tissues and that microvascular permeability is a rate-limiting step in extravascular coagulation.  相似文献   
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