全文获取类型
收费全文 | 149篇 |
免费 | 3篇 |
专业分类
电工技术 | 5篇 |
化学工业 | 45篇 |
金属工艺 | 1篇 |
机械仪表 | 4篇 |
建筑科学 | 2篇 |
矿业工程 | 1篇 |
能源动力 | 2篇 |
轻工业 | 17篇 |
水利工程 | 2篇 |
石油天然气 | 1篇 |
无线电 | 18篇 |
一般工业技术 | 6篇 |
冶金工业 | 31篇 |
原子能技术 | 4篇 |
自动化技术 | 13篇 |
出版年
2023年 | 2篇 |
2022年 | 5篇 |
2021年 | 2篇 |
2020年 | 1篇 |
2018年 | 2篇 |
2017年 | 1篇 |
2016年 | 2篇 |
2015年 | 2篇 |
2014年 | 4篇 |
2013年 | 5篇 |
2012年 | 4篇 |
2011年 | 11篇 |
2010年 | 4篇 |
2009年 | 1篇 |
2008年 | 9篇 |
2007年 | 3篇 |
2006年 | 6篇 |
2005年 | 3篇 |
2004年 | 7篇 |
2003年 | 4篇 |
2002年 | 7篇 |
2001年 | 5篇 |
2000年 | 4篇 |
1999年 | 8篇 |
1998年 | 5篇 |
1997年 | 7篇 |
1996年 | 10篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1992年 | 3篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1986年 | 1篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1977年 | 3篇 |
1976年 | 2篇 |
1968年 | 1篇 |
排序方式: 共有152条查询结果,搜索用时 500 毫秒
101.
M Olivero M Rizzo R Madeddu C Casadio S Pennacchietti MR Nicotra M Prat G Maggi N Arena PG Natali PM Comoglio MF Di Renzo 《Canadian Metallurgical Quarterly》1996,74(12):1862-1868
Hepatocyte growth factor/scatter factor (HGF/SF) stimulates the invasive growth of epithelial cells via the c-MET oncogene-encoded receptor. In normal lung, both the receptor and the ligand are detected, and the latter is known to be a mitogenic and a motogenic factor for both cultured bronchial epithelial cells and non-small-cell carcinoma lines. Here, ligand and receptor expression was examined in 42 samples of primary human non-small-cell lung carcinoma of different histotype. Each carcinoma sample was compared with adjacent normal lung tissue. The Met/HGF receptor was found to be 2 to 10-fold increased in 25% of carcinoma samples (P = 0.0113). The ligand, HGF/SF, was found to be 10 to 100-fold overexpressed in carcinoma samples (P < 0.0001). Notably, while HGF/SF was occasionally detectable and found exclusively as a single-chain inactive precursor in normal tissues, it was constantly in the biologically-active heterodimeric form in carcinomas. Immunohistochemical staining showed homogeneous expression of both the receptor and the ligand in carcinoma samples, whereas staining was barely detectable in their normal counterparts. These data show that HGF/SF is overexpressed and consistently activated in non-small-cell lung carcinomas and may contribute to the invasive growth of lung cancer. 相似文献
102.
Peptide Materials Obtained by Aggregation of Polyphenylalanine Conjugates as Gadolinium‐Based Magnetic Resonance Imaging Contrast Agents
下载免费PDF全文
![点击此处可从《Advanced functional materials》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Carlo Diaferia Eliana Gianolio Pasquale Palladino Francesca Arena Cinzia Boffa Giancarlo Morelli Antonella Accardo 《Advanced functional materials》2015,25(45):7003-7016
Peptide materials based on the aggregation of polyphenylalanine conjugates containing gadolinium complexes and acting as potential contrast agents (CAs) in magnetic resonance imaging (MRI) are described. Monomers contain two (F2) or four (F4) phenylalanine residues for self‐assembly, a chelating agent, 1,4,7,10‐tetraazacyclododecane‐N,N,N,N‐tetraacetic acid (DOTA) or diethylenetriaminepentaacetic acid (DTPA), for achieving gadolinium coordination, and ethoxylic linkers at two (L2) or six (L6) poly(ethylene glycol) (PEG) units between the chelating group and the peptide region. Both DOTA and DTPA tetraphenylalanine derivatives, and their gadolinium complexes DOTA(Gd)‐L6‐F4 and DTPA(Gd)‐L6‐F4, are able to self‐aggregate at very low concentration. Structural characterization, obtained by circular dichroism and infrared measurements, confirms the amyloid type fibril formation in which an antiparallel peptide alignment is preferred. Amyloid type fibril formation is also observed, in solid state, by transmission electron microscopy images and X‐ray diffraction patterns. The relaxivity values of DOTA(Gd)‐L6‐F4 and DTPA(Gd)‐L6‐F4 and their ability to enhance the MRI cellular response on the J774A.1 mouse macrophages cell line indicate that these peptide materials are promising candidate as a new class of supramolecular gadolinium based MRI contrast agents. 相似文献
103.
Ana Lidia Apás Javier Dupraz Romina Ross Silvia Nelina González Mario Eduardo Arena 《Journal of Bioscience and Bioengineering》2010,110(5):537-540
The application of potentially beneficial microorganisms to increase host defense is a new trend to increase health benefits. In this paper the first specific host probiotics for goats from a mixture isolated from healthy animals (Lactobacillus reuteri DDL 19, Lactobacillus alimentarius DDL 48, Enterococcus faecium DDE 39 and Bifidobacterium bifidum DDBA) was assayed. The effect of probiotic oral administration on goats' weight, gut microbiota, as well as on the production of mutagen compounds and their indicator (putrescine), were evaluated. The probiotic supplement was able to modify microflora balance by reducing Enterobacteria like Salmonella/Shigella (1.09 and 1.21 log CFU/g feces, respectively) and increasing lactic acid bacteria and Bifidobacteria (1.67 and 2.34 log CFU/g feces, respectively). The probiotics administration was correlated with a ten time diminution of fecal putrescine (cancer and bacterial disease marker) and a decrease of 60% mutagen fecal concentration, indicating the protective effect of the treatment. Additionally, a significant increase in ruminant weight was observed after probiotic administration. These results are encouraging towards the use of probiotic mixtures as functional food for goats. 相似文献
104.
Spencer Stacie M.; Lehman Jessica M.; Wynings Christina; Arena Patricia; Carver Charles S.; Antoni Michael H.; Derhagopian Robert P.; Ironson Gail; Love Neil 《Canadian Metallurgical Quarterly》1999,18(2):159
Much work on psychosocial sequelae of breast cancer has been guided by the assumption that body image and partner reaction issues are focal. In a tri-ethnic sample of 223 women treated for early-stage breast cancer within the prior year, the authors assessed a wider range of concerns and relations to well-being. Strongest concerns were recurrence, pain, death, harm from adjuvant treatment, and bills. Body-image concerns were moderate; concern about rejection was minimal. Younger women had stronger sexual and partner-related concerns than older women. Hispanic women had many stronger concerns and more disruption than other women. Life and pain concerns and sexuality concerns contributed uniquely to predicting emotional and psychosexual disruption; life and pain concerns and rejection concerns contributed to predicting social disruption. In sum, adaptation to breast cancer is a process bearing on several aspects of the patient's life space. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
Paolo Arena Sebastiano De Fiore Luigi Fortuna Mattia Frasca Luca Patané Guido Vagliasindi 《Autonomous Robots》2008,25(1-2):123-146
In this paper a new reactive layer for multi-sensory integration applied to robot navigation is proposed. The new robot navigation technique exploits the use of a chaotic system able to be controlled in real-time towards less complex orbits, like periodic orbits or equilibrium points, considered as perceptive orbits. These are subject to real-time modifications on the basis of environment changes acquired through a distributed sensory system. The strategy is inspired to the olfactory bulb neural activity observed in rabbits subject to external stimuli. The mathematical details of the approach are given including simulation results in a virtual environment. Furthermore the proposed strategy has been tested on an experimental environment consisting of an FPGA-based hardware driving an autonomous roving robot. The obtained results demonstrate the capability to perform a real-time navigation control. 相似文献
106.
Livatino S. Muscato G. Sessa S. Koffel C. Arena C. Pennisi A. Di Mauro D. Malkondu E. 《Robotics & Automation Magazine, IEEE》2008,15(4):58-67
Robot teleoperation is inherently related to sensor data transmission. Sensor data can be interpreted by the robotic system before being transmitted and presented to a user. This typically happens with sonar and laser sensors. In other cases, sensor data can directly be presented to a user to let him or her interpret the transmitted information. This happens, for example, with visual data. 相似文献
107.
Ten-year risk of false positive screening mammograms and clinical breast examinations 总被引:1,自引:0,他引:1
JG Elmore MB Barton VM Moceri S Polk PJ Arena SW Fletcher 《Canadian Metallurgical Quarterly》1998,338(16):1089-1096
BACKGROUND: The cumulative risk of a false positive result from a breast-cancer screening test is unknown. METHODS: We performed a 10-year retrospective cohort study of breast-cancer screening and diagnostic evaluations among 2400 women who were 40 to 69 years old at study entry. Mammograms or clinical breast examinations that were interpreted as indeterminate, aroused a suspicion of cancer, or prompted recommendations for additional workup in women in whom breast cancer was not diagnosed within the next year were considered to be false positive tests. RESULTS: A total of 9762 screening mammograms and 10,905 screening clinical breast examinations were performed, for a median of 4 mammograms and 5 clinical breast examinations per woman over the 10-year period. Of the women who were screened, 23.8 percent had at least one false positive mammogram, 13.4 percent had at least one false positive breast examination, and 31.7 percent had at least one false positive result for either test. The estimated cumulative risk of a false positive result was 49.1 percent (95 percent confidence interval, 40.3 to 64.1 percent) after 10 mammograms and 22.3 percent (95 percent confidence interval, 19.2 to 27.5 percent) after 10 clinical breast examinations. The false positive tests led to 870 outpatient appointments, 539 diagnostic mammograms, 186 ultrasound examinations, 188 biopsies, and 1 hospitalization. We estimate that among women who do not have breast cancer, 18.6 percent (95 percent confidence interval, 9.8 to 41.2 percent) will undergo a biopsy after 10 mammograms, and 6.2 percent (95 percent confidence interval, 3.7 to 11.2 percent) after 10 clinical breast examinations. For every 100 dollars spent for screening, an additional 33 dollars was spent to evaluate the false positive results. CONCLUSIONS: Over 10 years, one third of women screened had an abnormal test result that required additional evaluation, even though no breast cancer was present. Techniques are needed to decrease false positive results while maintaining high sensitivity. Physicians should educate women about the risk of a false positive result from a screening test for breast cancer. 相似文献
108.
Douglas Gouvea Agnès Smith David Stanley Smith Jean Pierre Bonnet Jose Arena Varela 《Journal of the American Ceramic Society》1997,80(10):2735-2736
Dense SnO2 -based ceramics (relative density >95%) have been obtained by natural sintering at a moderate temperature (≤ 1300°C) with the help of a small amount of manganese. Further thermal treatments above 1500°C result in grain growth and transport of manganese toward the sample surface. If the ceramic is embedded inside alumina powder, the diffusion of Mn out of the sample and into alumina during such heat treatments leads to a manganese-free body (<40 ppm) which is translucent. The transmission in the visible region depends on sample thickness; 61% was achieved for a 0.05 mm thick sample. 相似文献
109.
110.
Blanchard Edward B.; Andrasik Frank; Neff Debra F.; Arena John G.; Ahles Tim A.; Jurish Susan E.; Pallmeyer Thomas P.; Saunders Nancy L.; Teders Steven J.; Barron Kevin D.; Rodichok Lawrence D. 《Canadian Metallurgical Quarterly》1982,50(4):562
After a 4-wk baseline period during which daily ratings of headache activity were made and all participants took several psychological tests, 91 18–68 yr old patients with chronic headache (tension, migraine, and combined tension and migraine) were given a 10-session relaxation-training regimen. Ss who did not show substantial reductions in headache activity from the relaxation therapy were given a 12-session regimen of biofeedback (thermal biofeedback for vascular headaches and frontal EMG biofeedback for tension headaches). Relaxation therapy alone led to significant improvement for all groups, with a trend for the tension headache group to respond the most favorably. Biofeedback therapy led to further significant reduction in headache activity for all who received it, with a trend for combined migraine and tension headache patients to respond the most favorably. Multiple regression analyses revealed that approximately 32% of the variance in end-of-treatment headache diary scores could be predicted after relaxation and that 44% of the variance after biofeedback could be predicted using standard psychological tests. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献