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A new anthropometric landmark of the face, called the maxillozygion (mz; right, left) is presented. The bilateral landmark is the most prominent point of the maxillozygomatic suture line, identified by palpation of the most anterior protruding contours on the frontal aspect of the face, located below the lateral third of the right and left bony orbits. The reliability of locating the landmark on both sides of the face by palpation is discussed. Preliminary data determining the position of the maxillozygion in the vertical, sagittal, and horizontal planes in white and Asian sample populations is presented. In general, the Asian face tends to be the same width (zygion [zy]-zy) as the white face; however, the maxillozygion is located more laterally on the Asian face compared with the white face. 相似文献
14.
Observed the sexual behavior of 10 male rhesus monkeys before and after castration and during replacement therapy with testosterone propionate. In 10 tests before castration, all of the Ss ejaculated at least once, and in Weeks 21-25 and 51-55 after castration, 50 and 30%, respectively, ejaculated at least once. In the 35 postcastration tests given over a 55-wk period, 2 males did not ejaculate. 50% of the Ss achieved intromission 1 yr after castration. The percentage of castrated Ss showing intromission and ejaculation and the frequency of these responses were higher than those reported for most nonprimate species but did not differ greatly from those reported for the dog. Within 1 wk testosterone propionate restored whatever aspects of behavior were affected to precastration levels. (22 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
15.
M Blázquez PT Bosma EJ Fraser KJ Van Look VL Trudeau 《Canadian Metallurgical Quarterly》1998,119(3):345-364
Models are essential for the full understanding of neuroendocrine control processes. In this regard fish offer a rich source of biological material. They have diverse growth and reproductive strategies, inhabiting most of the Earth's aquatic ecological niches. Fish possess many of the common vertebrate features but also offer several unique aspects to allow the biologist easy access to the study of hypothalamic and pituitary function. Several key examples of how teleosts, or the bony fish, can offer insight into fundamental mechanisms of vertebrate sex differentiation, growth and reproduction are reviewed. 相似文献
16.
BACKGROUND: In amphibians, the Nieuwkoop center--a primary inducing region--has a central role in the induction of dorsal mesodermal cells to form the Spemann organizer. In teleosts, such as the zebrafish, Danio rerio, the functional equivalent of the amphibian Spemann organizer is the dorsal shield. Historically, a small region of the teleost yolk syncytial layer (YSL), an extraembryonic tissue that underlies the entire blastoderm, has been implicated in dorsal shield specification. Difficulties in transplanting discrete regions of the YSL and the previous lack of localized expression patterns unique to the YSL have, however, hindered efforts to prove definitively that the YSL possesses Nieuwkoop-center-like activities. RESULTS: Here, we describe the isolation and analysis of a new homeobox gene, called nieuwkoid, which is first expressed immediately following the mid-blastula transition on the dorsal side of the zebrafish pregastrula embryo. We found that, by the onset of gastrulation, nieuwkoid expression becomes localized to a restricted region of the YSL, directly underlying the future dorsal shield. Mis-expression of nieuwkoid in early zebrafish embryos was found to be sufficient for the induction of ectopic organizer regions and secondary axes. Mis-expression of nieuwkoid by cell transplantation or by direct injection into the YSL led to the non-autonomous induction of ectopic organizer gene expression. CONCLUSIONS: The dynamic and restricted expression of the nieuwkoid gene, combined with its potent dorsalizing activity, suggests that nieuwkoid is an important component in the regionalization of the gastrula organizer, possibly characterizing and mediating an organizer-inducing/Nieuwkoop-center-like activity. 相似文献
17.
F. C. Magne R. R. Mod G. Sumrell W. E. Parker R. E. Koos 《Journal of the American Oil Chemists' Society》1974,51(3):93-100
A number of N-mono and N,N-disubstituted amides of substituted and unsubstituted C18 fatty acids have been prepared and evaluated as base lubricants and lubricant additives. The neat epithioamides possess extreme
pressure lubricant characteristics and are noncorrosive at normal temperatures. The epithioamides also frequently function
as extreme pressure additives and antiwear agents for paraffinic or diester base oils, sometimes in both capacities for both
base oils. The intensiveness of these properties correlated directly with the degree of thiirane substitution in the compound.
Performance in both these capacities at the same levels of epithioation was dependent upon the N- or N,N-substituent groups
present.
One of 12 papers presented in the symposium “Novel Uses of Agricultural Oils” at the AOCS Spring Meeting, New Orleans, April
1973.
ARS, USDA. 相似文献
18.
Xin Zhao Antal A. Koos Bryan T.T. Chu Colin Johnston Nicole Grobert Patrick S. Grant 《Carbon》2009,47(3):561-569
High performance perfluoro alkoxy (PFA) and chemical vapor deposition-grown multi-walled carbon nanotube (MWCNT) composite films with thicknesses of 30 μm were prepared using a scalable spray deposition technique. A homogeneous distribution of MWCNTs within the PFA matrix was confirmed by electron and optical microscopy. Dielectric and AC conductivity measurements showed a significant enhancement of dielectric permittivity for PFA/MWCNT films at low frequencies, and a very weak dependence of dielectric permittivity on temperature in the range 25-230 °C. Very low percolation threshold volume fractions of ca. 0.0043 and 0.0017 were attained for MWCNTs with two different aspect ratios, which have been explained by an inherent feature of spray route, a microcapacitor model and percolation theory. The combination of PFA/MWCNT composites and the spray deposition route provides a promising approach for the fabrication of industrial scale composite films with well-controlled dielectric properties for micro-electronic and high temperature applications. 相似文献
19.
Dr. Tjibbe Bosma Dr. Rick Rink Dr. Markus A. Moosmeier Prof. Dr. Gert N. Moll 《Chembiochem : a European journal of chemical biology》2019,20(14):1754-1758
Many therapeutic peptides can still be improved with respect to target specificity, target affinity, resistance to peptidases/proteases, physical stability, and capacity to pass through membranes required for oral delivery. Several modifications can improve the peptides’ properties, in particular those that impose (a) conformational constraint(s). Screening of constrained peptides and the identification of hits is greatly facilitated by the generation of genetically encoded libraries. Recent breakthrough bacterial, phage, and yeast display screening systems of ribosomally synthesized post-translationally constrained peptides, particularly those of lanthipeptides, are earning special attention. Here we provide an overview of display systems for constrained, genetically encoded peptides and indicate prospects of constrained peptide-displaying phage and bacterial systems as such in vivo. 相似文献
20.
Minten IJ Wilke KD Hendriks LJ van Hest JC Nolte RJ Cornelissen JJ 《Small (Weinheim an der Bergstrasse, Germany)》2011,7(7):911-919
The cowpea chlorotic mottle virus (CCMV) is a versatile building block for the construction of nanoreactors and functional materials. Upon RNA removal, the capsid can be reversibly assembled and disassembed by adjusting the pH. At pH 5.0 the capsid is in the native assembled conformation, while at pH 7.5 it disassembles into 90 capsid protein dimers. This special property enables the encapsulation of various molecules, such as protein and enzymes, but only at low pH. It is possible to stabilize the capsid at pH 7.5 by addition of negatively charged polyelectrolytes or negatively charged particles, but these methods all fill the interior of the capsid, leaving little or no space for other cargo molecules. This pH restriction therefore severely limits the range of enzymes that can be encapsulated, and hampers the investigation of the CCMV capsid as a nanoreactor for the study of enzymes in confined spaces. Herein, the interaction of N-terminal histidine-tag-modified capsid proteins with several metal ions is reported. Depending on the conditions used, nanometer-sized protein particles or capsidlike architectures are formed that are stable at pH 7.5. This metal-mediated stabilization methodology is employed to form stable capsids containing multiple proteins at pH 7.5, thereby greatly expanding the scope of the CCMV capsid as a nanoreactor. 相似文献