全文获取类型
收费全文 | 850篇 |
免费 | 20篇 |
专业分类
林业 | 134篇 |
农学 | 11篇 |
基础科学 | 1篇 |
124篇 | |
综合类 | 58篇 |
农作物 | 4篇 |
水产渔业 | 22篇 |
畜牧兽医 | 471篇 |
园艺 | 20篇 |
植物保护 | 25篇 |
出版年
2023年 | 5篇 |
2021年 | 10篇 |
2020年 | 12篇 |
2019年 | 18篇 |
2018年 | 21篇 |
2017年 | 10篇 |
2016年 | 14篇 |
2015年 | 17篇 |
2014年 | 25篇 |
2013年 | 35篇 |
2012年 | 41篇 |
2011年 | 49篇 |
2010年 | 22篇 |
2009年 | 31篇 |
2008年 | 40篇 |
2007年 | 54篇 |
2006年 | 37篇 |
2005年 | 36篇 |
2004年 | 36篇 |
2003年 | 33篇 |
2002年 | 21篇 |
2001年 | 11篇 |
2000年 | 16篇 |
1999年 | 6篇 |
1998年 | 7篇 |
1995年 | 5篇 |
1992年 | 7篇 |
1991年 | 13篇 |
1990年 | 10篇 |
1989年 | 10篇 |
1988年 | 7篇 |
1986年 | 9篇 |
1984年 | 7篇 |
1982年 | 5篇 |
1981年 | 9篇 |
1979年 | 14篇 |
1978年 | 7篇 |
1973年 | 6篇 |
1972年 | 20篇 |
1971年 | 13篇 |
1970年 | 5篇 |
1969年 | 5篇 |
1968年 | 7篇 |
1966年 | 8篇 |
1905年 | 5篇 |
1902年 | 7篇 |
1901年 | 4篇 |
1897年 | 12篇 |
1896年 | 13篇 |
1895年 | 5篇 |
排序方式: 共有870条查询结果,搜索用时 562 毫秒
21.
Haemangiosarcomas of dogs were analysed by molecular genetic techniques. Regions of the tumour suppressor gene p53, including the well-known tumour hot spots (codons 175, 245, 248, 249, 273 and 282) were screened. A 24 bp deletion was detected in exon 5 of the gene. 相似文献
22.
Using a system for motion analysis, linear correlation of speed and forelimb lameness was measured in 16 horses trotting on a treadmill at a minimum of three different trotting speeds. Forelimb lameness was determined as asymmetry of vertical head motion during left and right forelimb stance.In seven horses with a moderate forelimb lameness (head motion asymmetry >40%), lameness increased significantly with trotting speed. In a further seven horses with mild or subclinical forelimb lameness (head motion asymmetry <40%) and in two horses with a moderate forelimb lameness, no significant correlation between speed and motion asymmetry was found.The results indicate that moderate forelimb lameness measured as head motion asymmetry depends on the speed at which the measurements are taken. If head motion asymmetry is measured at two trotting speeds, it can be standardized to any speed within the trotting speed range. 相似文献
23.
A case of basal cell carcinoma in a 10-year-old spaniel dog was analysed cytogenetically. A reciprocal translocation t(10;35) was detectable. 相似文献
24.
Twenty feline neoplasms were sequenced in the region from exons 5 to 8 for the presence of tumour suppressor gene p53 mutations. In a spindle cell sarcoma of the bladder, a missense mutation (codon 164 AAGGAG, lysineglutamic acid) in exon 5 was detected. In a pleomorphic sarcoma, a 23 bp deletion involving the splicing junction between intron 5 and exon 6 was observed. In a fibrosarcoma, a 6 bp deletion of p53 covering 2 bp of exon 7 and 4 bp of intron 7, including the splicing junction, was found. The study demonstrates three new p53 mutations in different types of sarcomas in cats. 相似文献
25.
Four mesenchymal neoplasms (two malignant fibroblastic histiocytomas, one fibrosarcoma, one fibroma) were investigated cytogenetically. Although no specific alterations were present, the frequent nonrandom involvement of chromosome E1 became clearly evident. Karyotypic alterations involving unrelated clonal changes were also present in the fibroma. 相似文献
26.
Ohne Zusammenfassung 相似文献
27.
28.
29.
Mayr und F. 《Forstwissenschaftliches Centralblatt》1896,18(6):353-359
Ohne Zusammenfassung 相似文献
30.
Ohne Zusammenfassung 相似文献