全文获取类型
收费全文 | 178篇 |
免费 | 17篇 |
国内免费 | 1篇 |
专业分类
林业 | 6篇 |
基础科学 | 2篇 |
9篇 | |
综合类 | 24篇 |
农作物 | 1篇 |
水产渔业 | 18篇 |
畜牧兽医 | 121篇 |
园艺 | 1篇 |
植物保护 | 14篇 |
出版年
2020年 | 3篇 |
2019年 | 2篇 |
2018年 | 4篇 |
2017年 | 3篇 |
2016年 | 4篇 |
2015年 | 2篇 |
2014年 | 5篇 |
2013年 | 9篇 |
2012年 | 6篇 |
2011年 | 3篇 |
2010年 | 4篇 |
2009年 | 3篇 |
2008年 | 4篇 |
2006年 | 7篇 |
2005年 | 3篇 |
2004年 | 6篇 |
2002年 | 7篇 |
2001年 | 8篇 |
2000年 | 4篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1992年 | 6篇 |
1991年 | 6篇 |
1990年 | 12篇 |
1989年 | 8篇 |
1988年 | 7篇 |
1986年 | 5篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1979年 | 2篇 |
1976年 | 4篇 |
1975年 | 1篇 |
1974年 | 2篇 |
1973年 | 4篇 |
1972年 | 4篇 |
1971年 | 4篇 |
1969年 | 2篇 |
1968年 | 4篇 |
1967年 | 2篇 |
1966年 | 7篇 |
1961年 | 1篇 |
1960年 | 1篇 |
1952年 | 1篇 |
1945年 | 1篇 |
1942年 | 1篇 |
1939年 | 1篇 |
1935年 | 1篇 |
1928年 | 1篇 |
1881年 | 1篇 |
排序方式: 共有196条查询结果,搜索用时 109 毫秒
91.
Eric R Pope 《Veterinary Clinics of North America: Small Animal Practice》2006,36(4):793-817
Injuries to the head and facial area are common in small animal surgery. Although many of the injuries at first may seem formidable, most can be repaired using basic reconstructive surgery procedures. The excel-lent blood supply in this area and the availability of local tissues provide many options for repairing most wounds. This article describes the indications and techniques for reconstructing wounds in this area. 相似文献
92.
93.
Reproductive tracts or tissues from five male black rhinoceroses (Diceros bicornis), two male white rhinoceroses (Ceratotherium simum), two male one-horned Asian rhinoceroses (Rhinoceros unicornis), seven female black rhinoceroses, and six female white rhinoceroses from multiple institutions were examined to characterize their anatomy and histology. Some observations and measurements were obtained from in situ tracts of intact animals before or during necropsy. Formalin-fixed tissues were dissected and examined histologically. Retrospective reproductive data from each rhinoceros was obtained from the institutions of origin. Reproductive histology of these species was similar to that of other mammals. Male accessory gland structure varied among species, and the Asian rhinoceros epididymis was more loosely attached and had larger duct diameters than did the epididymides of the African species. Although histology was typically mammalian, rhinoceros reproductive morphology combined characteristics of several different mammals. Defining this unique morphology of rhinoceroses may help in understanding their reproductive physiology and will effect the development of appropriate reproductive techniques. 相似文献
94.
E R Pope 《American journal of veterinary research》1985,46(12):2530-2535
The effects of 4 skin grafting techniques and graft survival on the secondary contraction of full-thickness skin grafts were evaluated. A total of 48 skin grafts were done on 12 dogs, with 2 skin grafts placed on both sides of the thorax of each dog. The grafting techniques included the sheet graft, sheet graft with continuous low-level suction provided by a butterfly catheter and evacuated glass tube, pie-crust graft, and nonexpanded mesh graft. Graft viability was assessed by visual inspection 10 days after surgical operation. Thirty skin grafts (64%) had a viability of 90% or greater. The final area of these grafts ranged from 73% to 119% of the original area. The secondary graft contraction followed a similar pattern for all graft types. During the first 10 days after surgical operation, the grafts contracted to 83% of their original area. Enlargement of the grafts began between 10 and 21 days after surgical operation. By 12 weeks, the grafts had attained a mean value of 96% of the original area. A significant difference in final area was not observed among graft types. Grafts with a high percentage of viability generally contracted less than those with larger areas of necrosis, but statistical relationship between viability and degree of contraction could not be proven. The results of the present study indicate that full-thickness skin grafts may be successfully done in dogs and that the grafts can be expected to undergo minimal postoperative contraction when graft survival is nearly complete. 相似文献
95.
Single-chain antigen-binding proteins 总被引:82,自引:0,他引:82
R E Bird K D Hardman J W Jacobson S Johnson B M Kaufman S M Lee T Lee S H Pope G S Riordan M Whitlow 《Science (New York, N.Y.)》1988,242(4877):423-426
Single-chain antigen-binding proteins are novel recombinant polypeptides, composed of an antibody variable light-chain amino acid sequence (VL) tethered to a variable heavy-chain sequence (VH) by a designed peptide that links the carboxyl terminus of the VL sequence to the amino terminus of the VH sequence. These proteins have the same specificities and affinities for their antigens as the monoclonal antibodies whose VL and VH sequences were used to construct the recombinant genes that were expressed in Escherichia coli. Three of these proteins, one derived from the sequence for a monoclonal antibody to growth hormone and two derived from the sequences of two different monoclonal antibodies to fluorescein, were designed, constructed, synthesized, purified, and assayed. These proteins are expected to have significant advantages over monoclonal antibodies in a number of applications. 相似文献
96.
Pope KO Pohl ME Jones JG Lentz DL von Nagy C Vega FJ Quitmyer IR 《Science (New York, N.Y.)》2001,292(5520):1370-1373
Archaeological research in the Gulf Coast of Tabasco reveals the earliest record of maize cultivation in Mexico. The first farmers settled along beach ridges and lagoons of the Grijalva River delta. Pollen from cultivated Zea appears with evidence of forest clearing about 5100 calendar years B.C. (yr B.C.) [6200 (14)C years before the present (yr B.P.)]. Large Zea sp. pollen, typical of domesticated maize (Zea mays), appears about 5000 calendar yr B.C. (6000 yr B.P.). A Manihot sp. pollen grain dated to 4600 calendar yr B.C. (5800 yr B.P.) may be from domesticated manioc. About 2500 calendar yr B.C. (4000 yr B.P.), domesticated sunflower seeds and cotton pollen appear as farming expanded. 相似文献
97.
98.
Abstract AIMS: To estimate the seroprevalence of antibodies to Erysipelothrix rhusiopathiae in chickens in New Zealand, and to estimate the effect of housing type, geographical location and age on seroprevalence. METHODS: A cross-sectional serological survey of a convenience sample of 545 broiler, breeder, and layer chickens in 55 flocks was conducted in 2010–2011. Birds were aged 5–83 weeks; housing types were free-range, shed, caged, and unknown; and flocks were located in the Auckland, Manawatu, North Canterbury, Otago, Taranaki, Waikato, and Wairarapa regions of New Zealand. An ELISA was used to measure antibodies to E. rhusiopathiae. Samples with an optical density reading ≥1.50 were considered to be positive. Logistic regression analysis was used to model the effect of housing type, geographical location and flock age on the prevalence of samples positive for antibodies to E. rhusiopathiae. RESULTS: The overall prevalence of samples with antibodies to E. rhusiopathiae was 39.8 (95% CI=35.68–44.06)% for the 545 samples, and 46/55 (84%) farms that were tested had at least one positive sample. Mean seroprevalence for types of housing was 44.2 (95% CI=37.79–50.70)% for free-range (n=240 birds), 23.7 (95% CI=17.83–30.38)% for shed (n=190), 73 (95% CI=56–86)% for caged (n=37) and 50 (95% CI=38–62)% for unknown (n=78). The disease was present in all seven geographical locations from which samples were obtained for this study. Seroprevalence increased with increasing age of birds (p<0.001); for birds ≤12 weeks of age it was 2 (95% CI=0.3–8)% (n=91), 13–24 weeks 29.1 (95% CI=23.34–35.46)% (n=230), 25–36 weeks 47 (95% CI=32–64)% (n=40), 37–48 weeks 75 (95% CI=51–91)% (n=20), >48 weeks 63.8 (95% CI=54.78–72.12)% (n=127). Neither housing type nor geographical location had a significant effect on the likelihood of samples being positive for antibodies to E. rhusiopathiae. CONCLUSIONS: The results of this study suggest the prevalence of erysipelas under New Zealand field conditions may be higher than expected and that the disease is significantly associated with increasing age. Housing type and geographical location appear to be unrelated to seroprevalence. CLINICAL RELEVANCE: Further study of the epidemiology of E. rhusiopathiae in chickens in New Zealand should be considered in order to minimise the extent of birds' exposure to the organism. These findings will assist in the design of further studies. 相似文献
99.
Replacement of the European wheat yellow rust population by new races from the centre of diversity in the near‐Himalayan region
下载免费PDF全文
![点击此处可从《Plant pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
M. S. Hovmøller S. Walter R. A. Bayles A. Hubbard K. Flath N. Sommerfeldt M. Leconte P. Czembor J. Rodriguez‐Algaba T. Thach J. G. Hansen P. Lassen A. F. Justesen S. Ali C. de Vallavieille‐Pope 《Plant pathology》2016,65(3):402-411
Isolates of recently spreading races of yellow rust from wheat and triticale in Europe were analysed using virulence phenotypic data of 2605 isolates sampled in 12 countries between 2000 and 2014. A subset of 239 isolates was investigated by microsatellite markers. At least three races of non‐European origin, termed ‘Warrior’, ‘Kranich’ and ‘Triticale aggressive’, were identified in the post‐2011 population. The Warrior race was already present in high frequencies in the first year of detection in most European countries and to a large extent it replaced the pre‐2011 European population. In contrast, the two other exotic races were localized to certain regions and/or crop type. The presence already of at least six multilocus genotypes of the Warrior race and five genotypes of the Kranich race in the first year of detection and across large areas is consistent with a hypothesis of aerial spread from genetically diverse source populations. A comparison with reference isolates sampled from six continents suggested that the Warrior and Kranich races originated from sexually recombining populations in the centre of diversity of the yellow rust fungus in the near‐Himalayan region of Asia. However, the Triticale aggressive race was most similar to populations in the Middle East/Central Asia. The study illustrated the potential role of sexual Puccinia striiformis populations as a reservoir for new races replacing distant clonal populations. 相似文献
100.
Although several studies have focused on how well anglers identify species using replicas and pictures, there has been no study assessing the confidence that can be placed in angler's ability to identify recreationally important fish. Understanding factors associated with low self‐confidence will be useful in tailoring education programmes to improve self‐confidence in identifying common species. The purposes of this assessment were to quantify the confidence of recreational anglers to identify 13 commonly encountered warm water fish species and to relate self‐confidence to species availability and angler experience. Significant variation was observed in anglers self‐confidence among species and levels of self‐declared skill, with greater confidence associated with greater skill and with greater exposure. This study of angler self‐confidence strongly highlights the need for educational programmes that target lower skilled anglers and the importance of teaching all anglers about less common species, regardless of skill level. 相似文献