全文获取类型
收费全文 | 307篇 |
免费 | 13篇 |
出版年
2023年 | 3篇 |
2022年 | 7篇 |
2021年 | 16篇 |
2020年 | 9篇 |
2019年 | 17篇 |
2018年 | 14篇 |
2017年 | 7篇 |
2016年 | 15篇 |
2015年 | 21篇 |
2014年 | 29篇 |
2013年 | 18篇 |
2012年 | 22篇 |
2011年 | 10篇 |
2010年 | 7篇 |
2009年 | 12篇 |
2008年 | 17篇 |
2007年 | 12篇 |
2006年 | 6篇 |
2005年 | 5篇 |
2004年 | 7篇 |
2003年 | 10篇 |
2002年 | 3篇 |
2001年 | 6篇 |
1999年 | 3篇 |
1996年 | 1篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1973年 | 3篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1970年 | 4篇 |
1969年 | 3篇 |
1966年 | 2篇 |
1965年 | 1篇 |
1963年 | 1篇 |
1956年 | 1篇 |
排序方式: 共有320条查询结果,搜索用时 31 毫秒
311.
312.
Bie Jia Zheng Keren Gao Xiang Liu Boyang Ma Jun Hayat Muhammad Abid Xiao Jianhua Wang Hongbin 《EcoHealth》2021,18(1):3-12
EcoHealth - Chytridiomycosis, a leading cause for the global decline in the number of amphibians, is caused by the fungal pathogen Batrachochytrium dendrobatidis. In this study, global distribution... 相似文献
313.
Ceratapion basicorne (Coleoptera: Apionidae) is a prospective biological control agent of yellow starthistle (Centaurea solstitialis, Asteraceae: Cardueae), which is an important invasive alien weed in the western United States. Previous studies have shown that it is possible for this insect to oviposit on and complete development on safflower (Carthamus tinctorius) under no-choice laboratory conditions; however, it has never been reported as a pest of safflower. Field experiments were conducted at three sites in eastern Turkey during 3 years to evaluate the risk of attack on safflower by this insect in its native range. At two sites where C. basicorne was the only apionid observed, no safflower plants were attacked despite high attack rates on yellow starthistle test plants (48–98% of plants infested). At a third site, where C. basicorne and three other species in the same genus; C. scalptum, C. orientale, and C. onopordi were present, 8–26% of safflower plants were infested, but none of the insects reared from safflower during 3 years were C. basicorne. Other authors have reported rearing C. basicorne from field-collected plants of only Ce. solstitialis, Ce. cyanus, Ce. depressa, and Cnicus benedictus. Our results indicate that C. basicorne does not attack safflower under field conditions and that its introduction would not pose a risk to this crop. 相似文献
314.
Homogeneously glycosylated proteins are essential for analyzing the structure of N-glycans, studying their consequences inside cells, and developing therapeutic glycoproteins. However, the isolation of glycoproteins with homogeneous glycans from human is difficult since glycoforms slightly differ from each other with respect to molecular weight and charge. Microbial expression systems have numerous benefits in expression technology and have gained great attention, because they are more adaptable to the biotechnology industry. While selecting an expression host, the glycosylation pattern must be taken into account, because glycosylation strongly depends on cellular production system and selected production clone. This review discussed the technological developments in glycoengineering of microbial expression systems for humanizing the glycosylation profile and highlighted the expression potential of Leishmania expression system. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2752, 2019. 相似文献
315.
Xian B. Mardiros Ronni Park Bryan Clifton Gurman Grewal Amina K. Khizar Therese A. Markow 《Fly》2016,10(4):162-171
Speciation can occur through the presence of reproductive isolation barriers that impede mating, restrict cross-fertilization, or render inviable/sterile hybrid progeny. The D. willistoni subgroup is ideally suited for studies of speciation, with examples of both allopatry and sympatry, a range of isolation barriers, and the availability of one species complete genome sequence to facilitate genetic studies of divergence. D. w. willistoni has the largest geographic distribution among members of the Drosophila willistoni subgroup, spanning from Argentina to the southern United States, including the Caribbean islands. A subspecies of D. w. willistoni, D. w. quechua, is geographically separated by the Andes mountain range and has evolved unidirectional sterility, in that only male offspring of D. w. quechua females × D. w. willistoni males are sterile. Whether D. w. willistoni flies residing east of the Andes belong to one or more D. willistoni subspecies remains unresolved. Here we perform fecundity assays and show that F1 hybrid males produced from crosses between different strains found in Central America, North America, and northern Caribbean islands are reproductively isolated from South American and southern Caribbean island strains as a result of unidirectional hybrid male sterility. Our results show the existence of a reproductive isolation barrier between the northern and southern strains and suggest a subdivision of the previously identified D. willistoni willistoni species into 2 new subspecies. 相似文献
316.
An interactive effect of nitric oxide and 24-epibrassinolide (EBL) or 28-homobrassinolide (HBL) was investigated in Lycopersicon esculentum Mill. cv. K-21. Seeds prior to sowing were exposed to sodium nitroprusside (SNP) (0, 10−5 M or 1 M), a nitric oxide donor, for 8 h, and the resulting seedlings were subsequently sprayed with 10−8 M EBL or HBL at 30-day stage. The analysis of plant samples after 24 h of the EBL or HBL spray showed that the lower SNP
concentration (10−5 M) favored the growth, pigment content, photosynthetic and enzymatic activities, and also improved the antioxidant system.
However, 1 M SNP had inhibitory impact on most of the indices, except the antioxidant system. Brassinosteroids (EBL or HBL),
on the other hand, had a stimulatory impact on the aforementioned indices. The inhibitory effect of SNP (1 M) was neutralized
by the application of BRs, where EBL was more effective than HBL. 相似文献
317.
Zusammenfassung Im Pankreas ausgewachsener Ratten wurden nach Alloxanschädigung Regenerationsherde beobachtet und beschrieben. Sie bestehen in einem büschelförmigen Aussprossen kleiner Gänge an umschriebenen Stellen des Organes, die in ein retikuläres Bindegewebe eingebettet sind. In analoger Weise wie bei der ontogenetischen Entwicklung des Pankreas aus den primitiven Drüsenschläuchen, kommt es auch im Bereiche der Gangwucherungen zur Neubildung von Inselgewebe. 相似文献
318.
BioMetals - Copper (Cu) is an essential mineral nutrient for the proper growth and development of plants; it is involved in myriad morphological, physiological, and biochemical processes. Copper... 相似文献
319.
320.