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   172篇
  免费   4篇
林业   1篇
农学   3篇
  25篇
综合类   29篇
农作物   1篇
水产渔业   2篇
畜牧兽医   113篇
园艺   1篇
植物保护   1篇
  2024年   1篇
  2022年   1篇
  2021年   6篇
  2020年   7篇
  2019年   5篇
  2018年   3篇
  2017年   1篇
  2016年   5篇
  2015年   2篇
  2014年   8篇
  2013年   11篇
  2012年   5篇
  2011年   8篇
  2010年   6篇
  2009年   6篇
  2008年   6篇
  2007年   10篇
  2006年   7篇
  2005年   5篇
  2004年   3篇
  2003年   5篇
  2002年   8篇
  2001年   4篇
  2000年   2篇
  1999年   6篇
  1998年   2篇
  1997年   2篇
  1994年   4篇
  1993年   1篇
  1992年   5篇
  1991年   3篇
  1990年   1篇
  1989年   2篇
  1988年   4篇
  1987年   5篇
  1986年   3篇
  1985年   2篇
  1984年   1篇
  1982年   1篇
  1981年   1篇
  1980年   2篇
  1978年   1篇
  1976年   2篇
  1974年   1篇
  1972年   1篇
  1965年   1篇
排序方式: 共有176条查询结果,搜索用时 0 毫秒
51.
52.
A six-year-old, female Tibetan terrier was referred for investigation of a non-healing wound on the left caudal thorax. A subcutaneous swelling had initially developed on the chest wall, followed by a draining tract from which seropurulent fluid drained for two months. There had been no response to antibiotic treatment. Following radiographic and ultrasonographic examinations, a bone sequestrum from a fractured rib or a foreign body was suspected. Surgical exploration of the wound identified a sinus tract and a wooden foreign body (an ice-lolly stick) was located in subcutaneous tissues. Partial wound dehiscence of the surgical site occurred postoperatively, but healed after 10 days. One month later, fluid began to discharge from the area again. Further surgical exploration confirmed a gastrocutaneous fistula. Dissection of the fistula and surgical closure of the stomach, body wall and skin led to resolution of all signs.  相似文献   
53.
Hypothyroidism was diagnosed in 50 dogs and excluded in 86 dogs suspected of hypothyroidism, on the basis of the results of bovine thyrotropin response tests. Breed, pedigree, sex or neutering status did not significantly influence the likelihood of the dogs being hypothyroid. The hypothyroid dogs were significantly older than the non-hypothyroid dogs referred to the University of Glasgow during the same period. However, when dogs under two years of age were excluded from the statistical analyses there was no significant difference in age between the two groups. The most common clinical characteristics associated with hypothyroidism were metabolic signs (84 per cent of cases), particularly lethargy (76 per cent), obesity or weight gain (44 per cent), and exercise intolerance (24 per cent); and dermatological abnormalities (80 per cent), including alopecia (56 per cent), poor coat quality (30 per cent) and hyperpigmentation (20 per cent). When compared with the laboratory reference limits the most common biochemical and haematological abnormalities were increased concentrations of triglycerides (88 per cent), cholesterol (78 per cent), glucose (49 per cent), and fructosamine (43 per cent), and increased activities of creatine kinase (35 per cent), and decreased concentrations of inorganic phosphate (63 per cent), and a low red blood cell count (40 per cent). When compared with reference limits derived from the euthyroid dogs the most common abnormalities were increased concentrations of gamma-glutamyltransferase (21 per cent), cholesterol (18 per cent), and aspartate aminotransferase (15 per cent) and a decreased red blood cell count (29 per cent), and decreased neutrophils (18 per cent) and decreased activity of creatine kinase (15 per cent). Assessment of cholesterol, creatine kinase, aspartate aminotransferase, gamma-glutamyltransferase, and red blood cell and neutrophil counts may be particularly useful in distinguishing hypothyroid dogs from euthyroid animals with similar clinical signs.  相似文献   
54.
Abstract

CASE HISTORY AND CLINICAL FINDINGS: Two White Dorper lambs from the North Island of New Zealand, 2 and 4 weeks of age, were presented with large skin flaps hanging from the flanks, separation of skin from the subcutis over mobile joints, and de-gloving injuries of the limbs and tail. The lambs were subject to euthanasia on humane grounds.

PATHOLOGICAL FINDINGS: Large skin tears with associated haemorrhage, periarticular S/C oedema and generalised skin fragility were observed in both lambs at post-mortem examination. Histology of the affected skin revealed diffuse hyalinisation of dermal collagen compared with control lambs, protein-filled peri-adnexal clefts and areas of deep dermal and S/C granulation tissue consistent with previous separation of skin from the subcutis. Analysis of hair follicles, collected from one of the lambs, using a commercially available genetic test in Australia was consistent with the lamb being homozygous for the mutation responsible for ovine dermatosparaxis.

DIAGNOSIS: Likely dermatosparaxis.

CLINICAL RELEVANCE: These findings strongly suggest that the mutation responsible for dermatosparaxis in White Dorper sheep is present in New Zealand. Dermatosparaxis should be considered when investigating skin fragility in lambs with White Dorper genetics. Confirmation of the disorder is possible through genetic analysis of hair follicles.  相似文献   
55.
56.
: Tetanus with hiatal hernia was diagnosed in a four-month-old female sheepdog pup. The animal was treated with tetanus antitoxin, antibiotics, fluids and intensive nursing care for three weeks and subsequently made a full recovery.  相似文献   
57.
Soil systems are characterized by the spatial and temporal distribution of organic and mineral particles, water and air within a soil profile. Investigations into the complex interactions between soil constituents have greatly benefited from the advent of non‐invasive techniques for structural analysis. In this paper we present a review of the application of one such technique, X‐ray computed tomography (CT), for studies of undisturbed soil systems, focusing on research during the last 10 years in particular. The ability to undertake three‐dimensional imaging has provided valuable insights regarding the quantitative assessment of soil features, in a way previously unachievable because of the opaque nature of soil. A dynamic approach to the evaluation of soil pore networks, hydro‐physical characteristics and soil faunal behaviour has seen numerous scanning methodologies employed and a diverse range of image analysis protocols used. This has shed light on functional processes across multiple scales whilst also bringing its own challenges. In particular, much work has been carried out to link a soil's porous architecture with hydraulic function, although new technical improvements allowing the characterization of organic matter and the influence of soil biota on structural development are showing great promise. Here we summarize the development of X‐ray CT in soil science, highlight the major issues relating to its use, outline some of the applications for overcoming these challenges and describe the potential of future technological advances for non‐invasive soil characterization through integration with other complementary techniques.  相似文献   
58.
59.
60.
Land use change (LUC) alters soil structure and, consequently, the functions and services provided by these soils. Conversion from extensive pasture to sugarcane is one of the largest land transitions in Brazil as a result of the growth of the domestic and global demands of bioenergy. However, the impacts of sugarcane expansion on the soil structure under extensive pasture remains unclear, especially when considering changes at the microscale. We investigated whether LUC for sugarcane cultivation impacted soil microstructure quality. Undisturbed soil samples were taken from two soil layers (0–10 and 10–20 cm) under three contrasting land uses (native vegetation—NV, pasture—PA and sugarcane—SC) in three different locations in the central-southern Brazil. Oriented thin sections (30 μm) were used for micromorphological analysis. The total area of pores decreased following the LUC in the following order: NV > PA > SC in both soil layers. The area of large complex packing pores (>0.01 mm²) also decreased with the LUC sequence: NV>PA>SC. Qualitative and semi-quantitative micromorphological analysis confirmed porosity reduction was driven by the decrease in complex packing pores and that biological features decreased in the same LUC sequence as the quantitative parameters. Therefore, LUC for sugarcane expansion reduced microscale soil porosity, irrespectively of soil type and site-specific conditions, indicating that the adoption of more sustainable management practices is imperative to preserve soil structure and sustain soil functions in Brazilian sugarcane fields.  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