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   48篇
  免费   0篇
轻工业   2篇
无线电   3篇
一般工业技术   9篇
冶金工业   26篇
原子能技术   1篇
自动化技术   7篇
  2013年   2篇
  2011年   1篇
  2010年   1篇
  2008年   1篇
  2006年   1篇
  2005年   1篇
  2004年   1篇
  2001年   1篇
  2000年   1篇
  1999年   1篇
  1998年   5篇
  1997年   7篇
  1996年   1篇
  1995年   2篇
  1994年   1篇
  1993年   4篇
  1989年   1篇
  1987年   2篇
  1986年   1篇
  1985年   1篇
  1984年   2篇
  1982年   1篇
  1980年   1篇
  1979年   1篇
  1977年   2篇
  1976年   3篇
  1975年   1篇
  1971年   1篇
排序方式: 共有48条查询结果,搜索用时 31 毫秒
1.
A central assumption in the goal theory literature is that the degree of commitment to the assigned goal moderates the effectiveness of the goal-setting procedure. However, attempts to empirically verify commitment's moderating role have generally met with failure, calling into question either widely used measures of goal commitment, the moderating assumption itself, or both. Three studies are described that address this issue. Results indicate that the moderation assumption is valid but is only relevant to 1 of 3 closely related motivational concepts that are commonly discussed under the heading of commitment: prechoice attitudes, the subsequent choice of a personal goal, and the maintenance of that choice. It is suggested that a view of commitment that more clearly distinguishes these concepts can provide a better guide for future empirical research than can existing viewpoints. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
3.
A high-throughput (HT) comprehensive analysis approach was developed for assaying proteins directly from human plasma. Proteins were selectively retrieved, by utilizing antibodies immobilized within affinity pipet tips, and eluted onto enzymatically active mass spectrometer targets for subsequent digestion and structural characterization. Several parameters, including uniform parallel protein elution from 96 affinity pipet tips, proper buffering for on-target digestion, termination of the digestion, and MALDI matrix (re)introduction, were evaluated and optimized. The approach was validated via parallel, high-throughput analysis of transthyretin (TTR) and transferrin (TRFE) from 96 identical plasma samples. The 96 parallel analyses for each protein were completed in less than 90 min, measured from protein extraction to insertion in the mass spectrometer. Virtually identical mass spectra were obtained from the 96 TTR analyses, characterized by the presence of 14 tryptic fragments that allowed TTR sequence mapping with 100% coverage. Database search returned TTR as the best match for all 96 data sets. In regard to the TRFE analyses, database searching using data from the 96 spectra returned TRFE as the best match for all but 1 of the spectra. TRFE was mapped with 47-69% sequence coverage, with gaps in the sequence coverage corresponding to the carbohydrate-containing peptide fragments and large and small trypsin fragments that fell outside the window of mass analysis. Overall, the combined high-throughput affinity capture-protein digestion approach showed high reproducibility and speed and yielded an exceptional level of protein characterization, suggesting its use in future population proteomics endeavors.  相似文献   
4.
A high-throughput mass spectrometric immunoassay (MSIA) system for the analysis of proteins directly from biological fluids is reported. A 96-well-format robotic workstation equipped with antibody-derivatized affinity pipet tips was used for the parallel extraction of specific proteins from samples and subsequent deposition onto 96-well arrayed matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) targets. Interferences from nonspecifically bound proteins were minimized through choice of appropriate affinity pipet tip derivatization chemistries. Sample preparation for MALDI-TOFMS was enhanced through the use of hydrophobic/hydrophilic contrasting targets, which also presented functionalities found to promote matrix/analyte crystal growth. Automated mass spectrometry was used in the unattended acquisition of data, resulting in an analysis rate of approximately 100 samples/h (biological fluid-->data). The quantitative MSIA of beta2m levels present in human plasma samples is given as illustration.  相似文献   
5.
A note on parametric image enhancement   总被引:5,自引:0,他引:5  
A method for defining image enhancement operators based upon a parametric family is considered. This family of operators can be used for either context-free or context-sensitive enhancement that can be used either locally or globally. A modification of this procedure is suggested whereby the estimation of the parameters is performed using statistics which allow for efficient use of cellular or neighborhood image processors rather than those computed using the usual arithmetic operations.  相似文献   
6.
Since the NIH received a request to investigate the high degree of hearing loss in a fire department in 1980, hearing loss among firefighters has become an area of increased investigation. The author identifies the sources of occupational noise in firefighting, looks at audiometric testing and recent research in firefighting noise, and presents guidelines for implementing hearing conservation programs.  相似文献   
7.
Rearrangements or loss of chromosome 17 are frequent events in breast tumors. Chromosome 17 contains at least four genes implicated in breast cancer (TP53, ERBB2 (Her2/neu), BRCA1, and NM23), as well as other putative tumor suppressor genes and oncogenes implicated in loss of heterozygosity or allelic imbalance studies. Allelic imbalance represents the addition or loss of genetic material in tumor samples, providing circumstantial evidence for the location of cancer related genes. We have analyzed a panel of 85 breast tumor/normal tissue pairs with 21 PCR-based short tandem repeat (STR) markers located at 17q12-qter to more precisely define regions of allelic imbalance and to determine their relation to clinical parameters. Our analysis revealed at least four common regions of allelic imbalance: proximal to BRCA1, including D17S800 (17q12); distal to NM23 around D17S787 (17q22); near the growth hormone (GH) locus, at D17S948 (17q23-24); and between markers D17S937 and D17S802 (17q25). These data also reveal that loss (or gain) of 17q genetic material correlates with poorly differentiated (grade III) tumors (P = < 0.001), high S phase fraction (P = 0.034), and positive TP53 immunohistochemical staining (P = 0.011). However steroid receptor status, ERBB2 (Her2/neu) staining, and aneuploidy do not correlate with allelic imbalance at 17q.  相似文献   
8.
9.
10.
The problem of deciding whether or not a classification of a Landsat agricultural scene is acceptable when no ground truth is available was addressed. The approach taken was to examine temporal trends of the Landsat mean vectors of crops. A procedure for agricultural crop classification was developed using a time series (multitemporal) of Landsat mean vectors for selected agricultural fields in Montana and Kansas for which ground truth was known. This procedure using the temporal trend of mean vectors (the temporal trend procedure) was then applied to the individual Landsat pixels in more than one hundred multitemporal data sets collected throughout the wheat growing regions of the United States. The resulting classifications have compared favorably to ground truth estimates for proportion of wheat in those cases where ground truth was available. This temporal trend procedure has been found to give estimates of the wheat proportion that are comparable to the best results obtained using maximum likelihood classification with photointerpreter defined training fields. This classification scheme utilizing a temporal trend procedure is referred to as the “Delta Classifier”. It is currently being used as an independent, end-of-the-growing-season check on the reasonableness of maximum likelihood results in a quasi-operational Large Scale experiment (MacDonald et al., 1975).  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