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   2765篇
  免费   251篇
  2023年   16篇
  2022年   15篇
  2021年   61篇
  2020年   31篇
  2019年   35篇
  2018年   48篇
  2017年   50篇
  2016年   88篇
  2015年   147篇
  2014年   157篇
  2013年   187篇
  2012年   231篇
  2011年   207篇
  2010年   141篇
  2009年   128篇
  2008年   183篇
  2007年   156篇
  2006年   156篇
  2005年   169篇
  2004年   170篇
  2003年   145篇
  2002年   137篇
  2001年   48篇
  2000年   27篇
  1999年   29篇
  1998年   31篇
  1997年   20篇
  1996年   10篇
  1995年   16篇
  1994年   15篇
  1993年   16篇
  1992年   16篇
  1991年   12篇
  1990年   12篇
  1989年   8篇
  1988年   15篇
  1987年   8篇
  1986年   5篇
  1985年   8篇
  1984年   4篇
  1983年   5篇
  1982年   9篇
  1980年   4篇
  1979年   7篇
  1978年   5篇
  1977年   5篇
  1976年   6篇
  1973年   3篇
  1972年   4篇
  1971年   2篇
排序方式: 共有3016条查询结果,搜索用时 15 毫秒
81.
We use chloroplast DNA sequencing to examine aspects of the pre-European Māori cultivation of an endemic New Zealand root crop, Arthropodium cirratum (rengarenga). Researching the early stages of domestication is not possible for the majority of crops, because their cultivation began many thousands of years ago and/or they have been substantially altered by modern breeding methods. We found high levels of genetic variation and structuring characterised the natural distribution of A. cirratum, while the translocated populations only retained low levels of this diversity, indicating a strong bottleneck even at the early stages of this species’ cultivation. The high structuring detected at four chloroplast loci within the natural A. cirratum range enabled the putative source(s) of the translocated populations to be identified as most likely located in the eastern Bay of Plenty/East Cape region. The high structuring within A. cirratum also has implications for the conservation of genetic diversity within this species, which has undergone recent declines in both its natural and translocated ranges.  相似文献   
82.
Peter Nick 《Protoplasma》2016,253(4):965-966
  相似文献   
83.
If we are to make meaningful and measurable progress in restoring New Zealand's biological heritage by 2050, a range of fundamental issues need to be addressed. These relate not just to restoration science but also to building ecosystem resilience in the wider socio‐economic and cultural context within which restoration occurs.  相似文献   
84.
85.
86.
Flow cytometry is an automated, laser- or impedance-based, high throughput method that allows very rapid analysis of multiple chemical and physical characteristics of single cells within a cell population. It is an extremely powerful technology that has been used for over four decades with filamentous fungi. Although single cells within a cell population are normally analysed rapidly on a cell-by-cell basis using the technique, flow cytometry can also be used to analyse cell (e.g. spore) aggregates or entire microcolonies. Living or fixed cells can be stained with a wide range of fluorescent reporters to label different cell components or measure different physiological processes. Flow cytometry is also suited for measurements of cell size, interaction, aggregation or shape using non-labelled cells by means of analysing their light scattering characteristics. Fluorescence-activated cell sorting (FACS) is a specialized form of flow cytometry that provides a method for sorting a heterogeneous mixture of cells into two or more containers based upon the fluorescence and/or light scattering properties of each cell. The major advantage of analysing cells by flow cytometry over microscopy is the speed of analysis: thousands of cells can be analysed per second or sorted in minutes. Drawbacks of flow cytometry are that specific cells cannot be followed in time and normally spatial information relating to individual cells is lacking. A big advantage over microscopy is when using FACS, cells with desired characteristics can be sorted for downstream experimentation (e.g. for growth, infection, enzyme production, gene expression assays or ‘omics’ approaches). In this review, we explain the basic concepts of flow cytometry and FACS, define its advantages and disadvantages in comparison with microscopy, and describe the wide range of applications in which these powerful technologies have been used with filamentous fungi.  相似文献   
87.
Opportunistic viruses are a major problem for immunosuppressed individuals, particularly following organ or stem cell transplantation. Current treatments are non-existent or suffer from problems such as high toxicity or development of resistant strains. We previously published that a trafficking inhibitor that targets a host protein greatly reduces the replication of human cytomegalovirus. This inhibitor was also shown to be moderately effective against polyomaviruses, another family of opportunistic viruses. We have developed a panel of analogues for this inhibitor and have shown that these analogues maintain their high efficacy against HCMV, while substantially lowering the concentration required to inhibit polyomavirus replication. By targeting a host protein these compounds are able to inhibit the replication of two very different viruses. These observations open up the possibility of pan-viral inhibitors for immunosuppressed individuals that are effective against multiple, diverse opportunistic viruses.  相似文献   
88.
89.
90.
A new black yeast species, Exophiala macquariensis is described that is a member of the ascomycete family Herpotrichiellaceae, order Chaetothyriales. The genus Exophiala is comprised of opportunistic pathogens isolated from clinical specimens as well as species recovered from hydrocarbon contaminated environments. Several species have been reported to be able to degrade benzene, toluene, ethylbenzene and xylenes. Here, a novel species of Exophiala (CZ06) previously isolated from a Sub-Antarctic, Macquarie Island soil that was spiked with Special Antarctic Blend diesel fuel (SAB) is described. This isolate has the capacity of toluene biodegradation at cold temperatures. Multilocus sequence typing showed that this fungus was closely related to the pathogenic species Exophiala salmonis and Exophiala equina. With the capacity to utilise hydrocarbons as a sole carbon source at 10 °C, this fungus has great potential for future bioremediation applications.  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