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   50篇
  免费   1篇
  3篇
综合类   16篇
农作物   2篇
水产渔业   5篇
畜牧兽医   22篇
园艺   2篇
植物保护   1篇
  2021年   1篇
  2020年   1篇
  2019年   1篇
  2018年   2篇
  2016年   1篇
  2014年   1篇
  2012年   1篇
  2011年   2篇
  2010年   4篇
  2009年   2篇
  2008年   3篇
  2007年   3篇
  2006年   2篇
  2004年   2篇
  2003年   1篇
  2002年   1篇
  2001年   2篇
  2000年   1篇
  1999年   1篇
  1998年   1篇
  1995年   1篇
  1992年   2篇
  1991年   1篇
  1988年   1篇
  1986年   1篇
  1985年   2篇
  1983年   1篇
  1981年   1篇
  1980年   3篇
  1979年   2篇
  1977年   1篇
  1971年   2篇
排序方式: 共有51条查询结果,搜索用时 15 毫秒
21.
Background: Transitional cell carcinoma (TCC) is the most common cancer of the urinary tract in dogs. The most frequent cause of death is urinary obstruction from the primary tumor. Standard medical therapy for TCC is only partially effective. Hypothesis/Objectives: Intravesical administration of mitomycin C (MMC) in dogs with invasive TCC will result in antitumor activity against the primary tumor and minimal systemic drug absorption. Animals: Thirteen privately owned dogs with naturally occurring, histopathologically diagnosed TCC of the urinary bladder. Methods: A prospective phase I trial was performed. MMC was given intravesically (600 μg/mL initial concentration) for 1 h/d for 2 consecutive days each month. The MMC concentration was escalated to a maximum of 800 μg/mL in groups of 3 dogs until the maximum tolerated dose (MTD) was determined. Serum assays for MMC were performed to determine the extent of systemic absorption of the MMC. Results: The MTD of MMC based on local toxicoses was 700 μg/mL (1‐h dwell time, 2 consecutive days). In addition, 2 dogs had severe myelosuppression and appeared to have systemic absorption of MMC. Five dogs had partial remission, and 7 dogs had stable disease. Conclusions: Intravesical MMC has antitumor activity in dogs with invasive TCC. Further study is needed to determine the cause of the myelosuppression associated with MMC administration, and to develop strategies to minimize this risk.  相似文献   
22.
Growth regulator herbicides, such as 2,4-D, dicamba, picloram, and aminopyralid, are commonly used to control broadleaf weeds in rangelands, noncroplands, and cereal crops. If applied to cereals at late growth stages, while the grasses are developing reproductive parts, the herbicides often reduce cereal seed production. We are researching methods for using this injury response to control invasive annual grasses in rangelands by depleting their short-lived seed banks. In a previous greenhouse study, we found picloram and dicamba reduced seed production of the invasive annual grass Japanese brome (Bromus japonicus Thunb.) by nearly 100%. However, this promising greenhouse finding needs to be corroborated in the field before growth regulators can be confidently recommended for invasive annual grass control. This research note describes a study conducted in eastern Montana suggesting growth regulators may provide excellent control of invasive annual grasses. Specifically, we found typical use rates of aminopyralid and picloram reduced Japanese brome seed production by more than 95% (based on sample means) when applied at three different plant growth stages. This promising result contributes to the accumulating body of evidence suggesting growth regulators may control invasive annual grasses.  相似文献   
23.
OBJECTIVE: To characterise Australian domestic dogkeeping practices relevant to canine health and welfare. PROCEDURE: A quantitative questionnaire was distributed nationally through Dog's Life magazine. Data on management practices, household and dog demographics from 690 Australian dogs in 485 self-selected respondent households were analysed using ordinal and binary regression. RESULTS: Several variables, relating to dog, owner and environment were associated with management practices. The size of the dog correlated positively with being fed outdoors (P < 0.001), gameplaying (P = 0.016) and being trained (P = 0.001) and negatively with time spent indoors (P < 0.001). Neutered dogs were more likely to be walked every day (P = 0.027) and have had prior treatment for unwelcome behaviours (P < 0.001) but less likely to be fed outdoors (P < 0.013). The number of children in the household correlated with the dog being fed outdoors (P < 0.001). The number of adult female humans in the household correlated with dog being neutered (P < 0.001) whereas the reverse was linked to number of adult male humans in the household (P < 0.013). Larger numbers of adult female humans in the household were associated with a higher incidence of prior treatment for unwelcome behaviours (P = 0.020). The number of dogs in the household correlated negatively with dogs being walked every day (P < 0.004) and gameplaying (P = 0.001). Pure bred dogs were more likely to have attended puppy preschool than cross breeds (P = 0.002). CONCLUSION: Reference to previous studies of Australian dog owners suggests that the current data are representative in terms of location of households, sex and age of dogs, however, the proportion of pure bred dogs in the current survey was surprisingly high. This was perhaps because respondents were from a particular sector of the Australian dog-owning population. It must be acknowledged that Dog's Life magazine readers may be atypical of Australian dog owners, nevertheless, the study demonstrates that variables relating to the dog, owner or environment can be used to characterise management styles.  相似文献   
24.
Old man saltbush ( Atriplex nummularia ) and river saltbush ( A. amnicola ) are widely used in commercial grazing systems on saline land in south-western Australia. Three hypotheses were tested during a 3-year study aimed at understanding the performance of weaner Merino sheep grazing saltbush-based pastures. The first hypothesis, that young Merino sheep grazing river saltbush would be better able to maintain live weight, body condition and would grow more wool than sheep grazing old man saltbush, was not supported by the data. Across the 3 years of the study, sheep grazing old man saltbush lost significantly less live weight and grew more wool (proportionately 0·06) than sheep grazing river saltbush. Differences in animal performance were considered to be associated with differences between the plant species in in vitro digestibility, concentrations of fibre, sulphur and crude protein in the herbage and the architecture of the Atriplex plants. The second and third hypotheses concerned supplementation strategies for sheep grazing saltbush. Three supplements were offered, namely barley grain, cereal straw or cereal hay, at a rate that approximated to one-third of the daily metabolizable energy requirements for maintenance of live weight. The performance of the sheep was higher when the grain supplement was offered but there was no effect of feeding roughage supplements compared to no supplementation. The findings suggested that the practice of feeding saltbush with adjacent crop stubbles is unlikely to be beneficial once any fallen grain has been consumed.  相似文献   
25.
Objective To summarize the medical knowledge surrounding aardvarks to date, to describe the ophthalmic examination of a specimen with a chronic history of an upper eyelid lesion, of an assumed blind left eye, and to detail the anesthesia procedure performed. Procedure A 23‐year‐old aardvark was examined under general anesthesia and multiple ocular abnormalities were detected in the left eye (globe deviation, corneal opacities, iridodonesis, and aphakia). A thickening of the palpebral conjunctiva affecting the medial upper eyelid with erosion of the normal eyelid margin anatomy was identified. The adnexal lesion was resected by a wedge resection and histopathology was performed. Suture breakdown 3 days postoperatively required a second surgery, where buried sutures were used. The surgical techniques and postoperative care are discussed. Results The histopathology revealed mucosal hyperplasia and moderate neutrophilic and lymphoplasmacytic blepharitis. No causal organisms were identified. Following initial wound dehiscence and a modified surgical technique, the upper eyelid healed without complication and retained complete function. Conclusions The eyelid lesion involved a benign inflammatory and hyperplastic pathology of unknown etiology. Adjusting routine ophthalmic surgical techniques to wildlife and zoo animals can be challenging and complicated. It is important to understand the nature of the animals being managed, their circadian cycle, and habitat, to adjust and individualize the surgical approach, instrumentation, suture material, and perioperative treatment.  相似文献   
26.
Swine may be examined to evaluate a disease state or a lowered economic performance or as a herd health consultation. As much of the examination as possible should be performed without handling the animal. A thorough history, evaluation of herd records, environmental examination, and herd examination should be performed prior to the evaluation of an individual animal. All necessary equipment should be available when starting the individual examination. The animals is then restrained and examined, and necessary samples are taken. Post-mortem examinations or slaughter house evaluations are a very frequent part of a health examination on swine. All samples taken should be in accordance with the standards of the laboratory that you use. You should work closely with the laboratory to obtain the best results. Physical examination of swine can be rewarding for the veterinarian as well as the producer. The most important aspect to remember is to have enough information and the proper equipment available to handle the animals for the minimal amount of time to gain the maximum benefits. Vietnamese pot-bellied pigs are similar to domestic swine in terms of their diseases and health but are dissimilar in management; pot-bellied pigs are frequently brought to the veterinarian for individual examinations. History is the most valuable part of the examination, followed by observation. Pot-bellied pigs prefer to be held securely with a hand under the chin and rump. The examination is conducted similarly to the examination of any companion animal. Chemical restraint often is necessary for sampling or minor surgical procedures. Owners should be consulted prior to the use of any restraint. This will help win their approval and confidence when working on their pets. While performing the physical examination, look at the pig's overall health as well as specific breed characteristics. Try to stay abreast of swine vaccination recommendations; you may be consulted in this regard. Most importantly, never forget even though they are pigs, pot-bellied pigs are companion animals and should be handled as such.  相似文献   
27.
After 3 years and 31 close flybys of Titan by the Cassini Orbiter, Titan was finally observed in the shocked solar wind, outside of Saturn's magnetosphere. These observations revealed that Titan's flow-induced magnetosphere was populated by "fossil" fields originating from Saturn, to which the satellite was exposed before its excursion through the magnetopause. In addition, strong magnetic shear observed at the edge of Titan's induced magnetosphere suggests that reconnection may have been involved in the replacement of the fossil fields by the interplanetary magnetic field.  相似文献   
28.
29.
30.
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