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31.
32.
33.
J. Stephen Lansing 《American anthropologist》1998,100(4):1017-1018
Sight Unseen. 1996. 27 minutes, color. film by Nicholas Kurzon. For more information contact Documentary Educational Resources, 101 Morse St., Watertown, MA 02172. 相似文献
34.
Bias of some commonly-used time series estimates 总被引:3,自引:0,他引:3
35.
James D. Myers Thomas C. Allison Sandra Bittner Brett Didier Michael Frenklach William H. Green Jr. Yen-Ling Ho John Hewson Wendy Koegler Carina Lansing David Leahy Michael Lee Renata McCoy Michael Minkoff Sandeep Nijsure Gregor von Laszewski David Montoya Luwi Oluwole Carmen Pancerella Reinhardt Pinzon William Pitz Larry A. Rahn Branko Ruscic Karen Schuchardt Eric Stephan A. Wagner Theresa Windus Christine Yang 《Cluster computing》2005,8(4):243-253
The Collaboratory for Multi-scale Chemical Science (CMCS) is developing a powerful informatics-based approach to synthesizing
multi-scale information in support of systems-based research and is applying it within combustion science. An open source
multi-scale informatics toolkit is being developed that addresses a number of issues core to the emerging concept of knowledge
grids including provenance tracking and lightweight federation of data and application resources into cross-scale information
flows. The CMCS portal is currently in use by a number of high-profile pilot groups and is playing a significant role in enabling
their efforts to improve and extend community maintained chemical reference information.
James D. Myers received his B.A. in Physics from Cornell University in 1985 and his Ph.D. in Chemistry from the University of California
at Berkeley in 1993. He is currently the Associate Director for Collaborative Technologies at the National Center for Supercomputing
Applications (NCSA) at the University of Illinois, Urbana Champaign. Dr. Myers is the lead investigator on the U.S. Department
of Energy (DOE) sponsored Scientific Annotation Middleware project (http://www.scidac.org/SAM/) (scientific content management,
semantic annotation, and records functionality) and is serving as the Chief Technical Officer for the DOE-sponsored Collaboratory
for Multiscale Chemical Science (CMCS) project. His is also the lead architect for the Mid-America Earthquake Center's MAEViz
hazard risk management collaboratory and co-lead of NCSA's Collaborative Large-scale Engineering Analysis Network for Environmental
Research (CLEANER) related cybercollaboratory effort. Open source software developed by Dr. Myers and his colleagues including
the electronic laboratory notebook (ELN) and the Collaborative Research Environment (CORE) real-time collaboration environment
have been downloaded from the Pacific Northwest National Laboratory (PNNL) Collaboratory website (http://collaboratory.pnl.gov)
by thousands of researchers and educators. Due to space limitations, individual bios for all 28 authors are not shown. The
CMCS project is led by Dr. Larry Rahn (rahn@sandia.gov) at Sandia National Laboratories. The team includes combustion researchers
and computer science researchers and developers at five DOE National Laboratories (Argonne, Lawrence Livermore, Los Alamos,
Pacific Northwest, and Sandia National Laboratories), the National Institute of Standards and Technology, Massachusetts Institute
of Technology, and the University of California, Berkeley. Current contact information and biographic information for team
members is available at http://cmcs.org/team.php. 相似文献
36.
Sequence variations in small-subunit ribosomal RNAs of Hartmannella vermiformis and their phylogenetic implications 总被引:1,自引:0,他引:1
Evidence of associations between free-living amoebas and human disease has
been increasing in recent years. Knowledge about phylogenetic relationships
that may be important for the understanding of pathogenicity in the genera
involved is very limited at present. Consequently, we have begun to study
these relationships and report here on the phylogeny of Hartmannella
vermiformis, a free-living amoeba that can harbor the etiologic agent of
Legionnaires' disease. Our analysis is based on studies of small-subunit
ribosomal RNA genes (srDNA). Nucleotide sequences were determined for
nuclear srDNA from three strains of H. vermiformis isolated from the United
Kingdom, Germany, and the United States. These sequences then were compared
with a sequence previously obtained for a North American isolate by J. H.
Gunderson and M. L. Sogin. The four genes are 1,840 bp long, with an
average GC content of 49.6%. Sequence differences among the strains range
are 0.38%-0.76%. Variation occurs at 19 positions and includes 2
single-base indels plus 14 monotypic and 3 ditypic single-base
substitutions. Variation is limited to eight helix/loop structures
according to a current model for srRNA secondary structure. Parsimony,
distance, and bootstrap analyses used to examine phylogenetic relationships
between the srDNA sequences of H. vermiformis and other eukaryotes
indicated that Hartmannella sequences were most closely related to those of
Acanthamoeba and the alga Cryptomonas. All ditypic sites were consistent
with a separation between European and North American strains of
Hartmannella, but results of other tests of this relationship were
statistically inconclusive.
相似文献
37.
The Tapora Landcare Group, operating on the Okahukura Peninsula, has the long-term goal of making this region predator fenced. The aim of this study was to obtain information on the current status of avian biodiversity and the bird community across the band of coastal wetlands on the Okahukura Peninsula. Bird counts were conducted and playback lures used to detect three cryptic wetland species: fernbirds (Bowdleria punctata); spotless crakes (Porzana tabuensis); and banded rails (Gallirallus philippensis). Fernbirds and banded rails were detected at seven of the eight wetland sites sampled whereas spotless crakes were detected at two sites. The native species with the highest relative abundance across the eight sites were silvereyes (Zosterops lateralis) and South Island pied oystercatchers (Haematopus finschi). Changes in avian biodiversity over time in the region can now be monitored, and comprehensive long-term data on the status of avian biodiversity over time obtained. 相似文献
38.
R S English J S Lampel TJ Vanden Boom 《Journal of industrial microbiology & biotechnology》1998,21(4-5):219-224
The introduction of plasmid DNA into germinating spores of an industrially improved strain of Saccharopolyspora erythraea was accomplished by electroporation. Various parameters affecting the efficiency of electroporation were examined. The most
critical factor was the extent of spore germination. Electrocompetence was limited to a 4-h period following the initial emergence
of the germ tube. Electroporation efficiencies as high as 2 × 105 CFU μg−1 of plasmid DNA were obtained using electrocompetent germlings. The optimal field strength was 12–14 kV cm−1 with a pulse duration of 15–20 ms. Electrocompetent germlings were stored at −80°C without a significant decrease in transformation
efficiency. The utility of this protocol was demonstrated by isolating a propionyl-CoA carboxylase mutant through targeted
gene disruption and replacement.
Received 3 April 1998/ Accepted in revised form 28 September 1998 相似文献
39.
Nina Senutovitch Lawrence Vernetti Robert Boltz Richard DeBiasio Albert Gough D Lansing Taylor 《Experimental biology and medicine (Maywood, N.J.)》2015,240(6):795-808
This mini-review discusses the evolution of fluorescence as a tool to study living cells and tissues in vitro and the present role of fluorescent protein biosensors (FPBs) in microphysiological systems (MPSs). FPBs allow the measurement of temporal and spatial dynamics of targeted cellular events involved in normal and perturbed cellular assay systems and MPSs in real time. FPBs evolved from fluorescent analog cytochemistry (FAC) that permitted the measurement of the dynamics of purified proteins covalently labeled with environmentally insensitive fluorescent dyes and then incorporated into living cells, as well as a large list of diffusible fluorescent probes engineered to measure environmental changes in living cells. In parallel, a wide range of fluorescence microscopy methods were developed to measure the chemical and molecular activities of the labeled cells, including ratio imaging, fluorescence lifetime, total internal reflection, 3D imaging, including super-resolution, as well as high-content screening. FPBs evolved from FAC by combining environmentally sensitive fluorescent dyes with proteins in order to monitor specific physiological events such as post-translational modifications, production of metabolites, changes in various ion concentrations, and the dynamic interaction of proteins with defined macromolecules in time and space within cells. Original FPBs involved the engineering of fluorescent dyes to sense specific activities when covalently attached to particular domains of the targeted protein. The subsequent development of fluorescent proteins (FPs), such as the green fluorescent protein, dramatically accelerated the adoption of studying living cells, since the genetic “labeling” of proteins became a relatively simple method that permitted the analysis of temporal–spatial dynamics of a wide range of proteins. Investigators subsequently engineered the fluorescence properties of the FPs for environmental sensitivity that, when combined with targeted proteins/peptides, created a new generation of FPBs. Examples of FPBs that are useful in MPS are presented, including the design, testing, and application in a liver MPS. 相似文献
40.
Reini W Bretveld Chris MG Thomas Paul TJ Scheepers Gerhard A Zielhuis Nel Roeleveld 《Reproductive biology and endocrinology : RB&E》2006,4(1):30
Some pesticides may interfere with the female hormonal function, which may lead to negative effects on the reproductive system
through disruption of the hormonal balance necessary for proper functioning. Previous studies primarily focused on interference
with the estrogen and/or androgen receptor, but the hormonal function may be disrupted in many more ways through pesticide
exposure. The aim of this review is to give an overview of the various ways in which pesticides may disrupt the hormonal function
of the female reproductive system and in particular the ovarian cycle. Disruption can occur in all stages of hormonal regulation:
1. hormone synthesis; 2. hormone release and storage; 3. hormone transport and clearance; 4. hormone receptor recognition
and binding; 5. hormone postreceptor activation; 6. the thyroid function; and 7. the central nervous system. These mechanisms
are described for effects of pesticide exposure in vitro and on experimental animals in vivo. For the latter, potential effects of endocrine disrupting pesticides on the female reproductive system, i.e. modulation
of hormone concentrations, ovarian cycle irregularities, and impaired fertility, are also reviewed. In epidemiological studies,
exposure to pesticides has been associated with menstrual cycle disturbances, reduced fertility, prolonged time-to-pregnancy,
spontaneous abortion, stillbirths, and developmental defects, which may or may not be due to disruption of the female hormonal
function. Because pesticides comprise a large number of distinct substances with dissimilar structures and diverse toxicity,
it is most likely that several of the above-mentioned mechanisms are involved in the pathophysiological pathways explaining
the role of pesticide exposure in ovarian cycle disturbances, ultimately leading to fertility problems and other reproductive
effects. In future research, information on the ways in which pesticides may disrupt the hormonal function as described in
this review, can be used to generate specific hypotheses for studies on the effects of pesticides on the ovarian cycle, both
in toxicological and epidemiological settings. 相似文献