首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   148篇
  免费   15篇
林业   2篇
农学   3篇
  18篇
综合类   10篇
水产渔业   10篇
畜牧兽医   113篇
园艺   4篇
植物保护   3篇
  2021年   1篇
  2020年   8篇
  2019年   5篇
  2018年   3篇
  2017年   6篇
  2016年   5篇
  2015年   6篇
  2014年   1篇
  2013年   9篇
  2012年   6篇
  2011年   9篇
  2010年   7篇
  2009年   5篇
  2008年   12篇
  2007年   12篇
  2006年   7篇
  2005年   9篇
  2004年   8篇
  2003年   13篇
  2002年   15篇
  2001年   2篇
  2000年   1篇
  1997年   1篇
  1996年   1篇
  1992年   1篇
  1991年   2篇
  1990年   2篇
  1989年   1篇
  1986年   2篇
  1985年   1篇
  1980年   1篇
  1976年   1篇
排序方式: 共有163条查询结果,搜索用时 15 毫秒
1.
Testing all the cattle in an entire state with a uniform procedure for each animal affords an opportunity to relate human injury data to a known number of animals handled while carrying out a standardized procedure. Our objective was to describe the type and incidence density of injuries associated with TB-testing a large number of cattle herds, and to delineate the various factors associated with the risk of injury. A survey was mailed to all veterinarians (N = 259) who had completed at least five official bovine TB (bTB) herd tests in Michigan in 2001. We collected data regarding basic demographics and health status, work experience, veterinary specialty, and practice information. Each veterinarian was also requested to complete a separate injury questionnaire for each injury received while TB testing livestock in 2001. Accurate addresses were found for 247 eligible veterinarians, 175 (71%) of whom returned the survey. Thirty-six veterinarians reported a total of 53 injuries (10 major, 12 minor and 31 self-treated). Hands (29%) and legs (21%) were the anatomic locations most frequently injured, with sprains/strains (30%) and abrasion/contusion (30%) the most common types of injuries sustained. The overall incidence density of injuries was 1.9 per 10,000 animals tested. Female gender (RR = 3.3), being employed by the government (RR = 4.5), and smoking (RR = 6.0) were significantly associated with a higher rate of injury. Significant colliniearities were found between some risk factors associated with an increased rate of injury and participants thought 81% of their injuries could have been prevented. These results are explained by the administrative structure of the bTB testing program in Michigan, and the changing demographics of the veterinary workforce.  相似文献   
2.
Objective: To characterize the impact of age, gender, location and individual animal variation on the composition of articular cartilage from the metacarpophalangeal joint of horses. Design: Cartilage specimens were obtained from the metacarpophalangeal joints of 28 male, female and castrated male horses ranging in age from one day to 27 years of age. Cartilage samples from the distal metacarpus, proximal first phalanx and proximal sesamoids were analyzed separately. Chondrocyte number, DNA content, proteoglycan concentration and total collagen content were determined for each animal and joint location. Results: Age and joint location had a significant effect on chondrocyte number and DNA content with higher cell counts and DNA content detected in cartilage from the youngest age groups and in cartilage from the metacarpus and proximal sesamoids. The influence of age on chondrocyte numbers was not significant in horses over two years of age. Both age and joint location also influenced total proteoglycan and collagen content. Lower proteoglycan and collagen concentrations were detected in younger horses, and cartilage from the metacarpus had lower proteoglycan and collagen concentrations than that from other joint locations. Gender did not appear to influence chondrocyte number or matrix content of equine articular cartilage. However, there was significant residual variation in cellularity, proteoglycan levels and collagen content between individual animals that could not be explained by the signalment factors considered in this study. Conclusions: Future studies examining equine articular cartilage should avoid direct morphologic comparisons between animals of different ages, and any comparisons made between individuals should be interpreted cautiously. In addition, in vitro tissue culture models should avoid the use of cartilage pooled from different animals or from different locations within the same joint.  相似文献   
3.
Fourteen dogs with perianal fistulas were entered into a prospective clinical study to investigate the effects of long-term azathioprine on clinical outcome and to determine if the clinical results correlated with lymphocyte blastogenesis tests. Complete remission of perianal fistulas was seen in eight (57%) of 14 dogs; partial remission occurred in one (7%) dog; and no response was detected in five (36%) dogs. The results of lymphocyte blastogenesis assays did not correlate with therapeutic response.  相似文献   
4.
The presence and numbers of bovine herpesvirus 4 (BoHV-4) infected CD11b+ leukocytes were investigated during experimental infections of New Zealand White rabbits by Fluorescence Activated Cell Sorter (FACS) analysis. Peripheral blood leukocytes (PBL) were collected every second day, and the cells were stained with phycoerythrin-labelled CD11b-specific mouse monoclonal antibody and fluorescein-conjugated bovine herpesvirus 4-specific mouse monoclonal antibody. The numbers of double-stained cells from PBLs of the control and inoculated groups were measured and compared in FACSTREK analyser. Double-stained cells were detected in the virus-inoculated group on postinoculation days (PID) 2-5 and 9-12. The results indicated that CD11b+ PBLs were permissive for BoHV-4 infection, and are probably the main reservoir of the virus during the latent period. The data did not indicate production of infectious viral particles, but virus-specific proteins were expressed on the surface of CD11b+ cells. The two waves of double-stained cells gave similar results to the PCR assays from serum samples, which showed the presence of viral DNA in the serum on the same days when virus-infected CD11b cells were also present. Productive BoHV-4 infection of mast cells or undifferentiated leukocytes in the bone marrow and the antiviral immune response might be responsible for this periodic appearance of the virus in CD11b+ PBLs and in the serum. The paper provides evidence that CD11b+ PBLs are the main target cell populations in the blood for BoHV-4.  相似文献   
5.
6.
The next generation of biotechnology-derived products with the combined benefit of herbicide tolerance and insect protection (MON 88017) was developed to withstand feeding damage caused by the coleopteran pest corn rootworm and over-the-top applications of glyphosate, the active ingredient in Roundup herbicides. As a part of a larger safety and characterization assessment, MON 88017 was grown under field conditions at geographically diverse locations within the United States and Argentina during the 2002 and 2003-2004 field seasons, respectively, along with a near-isogenic control and other conventional corn hybrids for compositional assessment. Field trials were conducted using a randomized complete block design with three replication blocks at each site. Corn forage samples were harvested at the late dough/early dent stage, ground, and analyzed for the concentration of proximate constituents, fibers, and minerals. Samples of mature grain were harvested, ground, and analyzed for the concentration of proximate constituents, fiber, minerals, amino acids, fatty acids, vitamins, antinutrients, and secondary metabolites. The results showed that the forage and grain from MON 88017 are compositionally equivalent to forage and grain from control and conventional corn hybrids.  相似文献   
7.
The use of electron microscopy to assist in the rapid diagnosis of virus diseases of veterinary importance is reviewed. Electron microscopy can be used to assist the laboratory diagnosis of a virus disease at two stages during the investigation; either by demonstrating virus in clinical material or by identifying isolates from tissue culture or similar systems. Direct electron microscopy and immunoelectron microscopy are particularly useful for rapid diagnosis. The advantages of electron microscopy lie in speed and flexibility, and the disadvantages in the high particle concentration needed and the presumptive nature of a diagnosis.  相似文献   
8.
OBJECTIVE: To measure apolipoproteins in cerebrospinal fluid (CSF) from healthy mares and to determine whether CSF concentrations of apolipoproteins change during pregnancy and lactation. ANIMALS: 5 healthy pregnant mares. PROCEDURE: 2 sets of CSF samples were obtained; initial samples were obtained 10 to 30 days before parturition (mean, 18 days; median, 17 days), and second samples were obtained 19 to 26 days after parturition (mean, 23 days; median, 23 days). Cerebrospinal fluid was collected from the lumbosacral subarachnoid space of standing horses by use of routine collection techniques. Cerebrospinal fluid cholesterol concentrations were measured by use of a sensitive enzymatic assay. Ultracentrifugal fractions of CSF lipoproteins were characterized by determining the distribution of apolipoproteins, using polyacrylamide gel electrophoresis. RESULTS: Analyses of isolated ultracentrifugal fractions by polyacrylamide gel electrophoresis revealed 2 apolipoproteins, with the expected molecular weights for apolipoprotein E and apolipoprotein A-I. No significant differences were observed between pre- and postpartum values in mares. The concentration of cholesterol in CSF fluid of mares was comparable to values reported in other mammals. CONCLUSIONS AND CLINICAL RELEVANCE: Apolipoprotein E in CSF of horses is a major apolipoprotein associated with high-density lipoproteins, which is similar to findings in other mammals. Additional characterization of the role of apolipoproteins in mammalian CSF may provide critical insight into various degenerative neurologic disease processes.  相似文献   
9.
OBJECTIVE: To describe the ultrasonographic and quantitative histologic effect of injecting 2% iodine in almond oil (IAO) and ethanolamine oleate (EO) in the medial and middle patellar ligaments of horses and to determine whether a difference in response exists between IAO and EO treatment. ANIMALS: 10 healthy horses. PROCEDURE: In 5 horses, the medial and middle patellar ligaments of 1 limb were injected with EO, whereas IAO was injected in the medial and middle patellar ligaments of another 5 horses. Ultrasonographic evaluation was performed on the experimental and control limb before injection of IAO and EO and prior to euthanasia to determine cross-sectional area and evaluate fiber pattern. The patellar ligaments were harvested 2 weeks after injection and examined histologically to evaluate the inflammatory response, fibroplasia, and chondroid metaplasia. RESULTS: Injection of the patellar ligaments with IAO resulted in a greater increase in cross-sectional area on ultrasonography than EO. Both agents caused a decrease in echogenicity of the ligament. Histologically, significantly greater infiltration of inflammatory cells and fibroplasia developed after injection with IAO, compared with EO. Both agents resulted in significantly greater fibroplasia relative to control specimens. CONCLUSIONS AND CLINICAL RELEVANCE: Injection of the medial and middle patellar ligaments with IAO induces more severe inflammation and fibroplasia than EO. Maturation of the inflammatory and fibrous response may contribute to resolution or attenuation of upward fixation of the patella by subsequent stiffening of the ligaments.  相似文献   
10.
The use of flow cytometry in veterinary diagnostics is becoming a valuable clinical tool with a broad range of applications. Physical characteristics of cells can be determined by the flow cytometer laser and electronics through the measurement of changes in light scatter properties. Other components and functions of cells can be defined through the application of fluorochrome dyes that have an affinity for cellular components. Traditionally, common clinical applications are immunophenotyping of cells of the hematopoietic system with fluorescent-labeled antibodies raised against specific cell surface proteins. Other approaches have been used to elucidate changes in cell function and DNA content. This review is intended to provide the reader with the fundamental uses of flow cytometry. Examples of clinical applications in equine patients include immune-mediated hemolytic anemia, immune-mediated thrombocytopenia (IMT), chronic inflammatory disease, and neoplasia.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号