全文获取类型
收费全文 | 97282篇 |
免费 | 4783篇 |
国内免费 | 61篇 |
专业分类
林业 | 4387篇 |
农学 | 2957篇 |
基础科学 | 521篇 |
11134篇 | |
综合类 | 18396篇 |
农作物 | 3856篇 |
水产渔业 | 4542篇 |
畜牧兽医 | 49295篇 |
园艺 | 1136篇 |
植物保护 | 5902篇 |
出版年
2018年 | 1215篇 |
2017年 | 1357篇 |
2016年 | 1258篇 |
2015年 | 1056篇 |
2014年 | 1328篇 |
2013年 | 3429篇 |
2012年 | 2353篇 |
2011年 | 2855篇 |
2010年 | 1941篇 |
2009年 | 1867篇 |
2008年 | 2849篇 |
2007年 | 2866篇 |
2006年 | 2566篇 |
2005年 | 2432篇 |
2004年 | 2300篇 |
2003年 | 2377篇 |
2002年 | 2187篇 |
2001年 | 2829篇 |
2000年 | 2859篇 |
1999年 | 2352篇 |
1998年 | 928篇 |
1997年 | 936篇 |
1995年 | 1033篇 |
1993年 | 895篇 |
1992年 | 1829篇 |
1991年 | 1977篇 |
1990年 | 2012篇 |
1989年 | 1962篇 |
1988年 | 1845篇 |
1987年 | 1812篇 |
1986年 | 1813篇 |
1985年 | 1817篇 |
1984年 | 1519篇 |
1983年 | 1382篇 |
1982年 | 973篇 |
1981年 | 882篇 |
1979年 | 1595篇 |
1978年 | 1223篇 |
1977年 | 1092篇 |
1976年 | 1073篇 |
1975年 | 1208篇 |
1974年 | 1484篇 |
1973年 | 1491篇 |
1972年 | 1490篇 |
1971年 | 1379篇 |
1970年 | 1277篇 |
1969年 | 1262篇 |
1968年 | 1103篇 |
1967年 | 1197篇 |
1966年 | 1115篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
151.
On a property in the Nelson District, blood and urine samples were taken from red deer (Cervus elaphus) from which low (<1:100) antibody titres to serovar copenhageni and suspected leptospiral abortions had previously been reported. A total of 27 hinds were sampled. Microscopic agglutination test (MAT) titres in sera ranging from 1:32 to 1:128 were found in six animals. Thirteen leptospiral isolations were made from nine of the 27 urine samples. Four of these were typed as copenhageni and nine as hardjo. Two cultures were prepared from each urine sample and hardjo and copenhageni were both isolated from single urine samples from two animals. None of the 27 deer had serum MAT titres at 1:32 or above to copenhageni. 相似文献
152.
153.
154.
155.
156.
157.
Submitting canine blood for prothrombin time and partial thromboplastin time determinations 总被引:2,自引:1,他引:1
Smalko D Johnstone IB Crane S 《The Canadian veterinary journal. La revue veterinaire canadienne》1985,26(4):135-136,137
Practitioners commonly submit samples from dogs for partial thromboplastin time and prothrombin time determinations. Controversy exists as to the necessity for rapid separation of plasma and cells, and submission of the plasma on ice (or frozen). The purpose of this study was to address three questions. First, is it better to submit plasma or is whole blood satisfactory? Second, is it necessary to refrigerate the sample or is maintenance at room temperature (20° C) adequate? Third, does the sample have to arrive at the laboratory within a few hours of collection or can reliable partial thromboplastin time/prothrombin time determinations be made on samples up to 48 hours old?It has been shown by this study that reliable partial thromboplastin time and prothrombin time determinations can be carried out on canine plasma for up to 48 hours after collection regardless of whether or not the plasma is separated immediately; however the samples must be kept at 4°C. If the samples are maintained at room temperature, reliable prothrombin time determinations can be obtained for up to six hours after collection regardless of whether or not the plasma is separated immediately. Reliable partial thromboplastin time determinations can be made on plasma stored at 20°C for up to 24 hours after collection and possibly longer (up to 48 hours) if the plasma has been separated immediately. 相似文献
158.
Wobeser G Gajadhar AA Hunt HM 《The Canadian veterinary journal. La revue veterinaire canadienne》1985,26(8):241-244
Infection with Fascioloides magna, the large American liver fluke, was diagnosed in two moose (Alces alces) and six wapiti (Cervus elaphus) from central Saskatchewan. This is believed to be the first record of the parasite in the province. Fecal samples collected from wild wapiti at five sites in the commercial forest zone in Saskatchewan contained eggs believed to be those of F. magna. Trematode eggs were not found in feces from five captive herds of wapiti in the province, nor in samples from wild wapiti in Moose Mountain Provincial Park. Operculate eggs were found in feces of wild wapiti from Cypress Hills, but these were believed to be from trematodes other than F. magna. The distribution and significance of F. magna in Canada, based partially on responses to a mail questionnaire, are reviewed. 相似文献
159.
160.