全文获取类型
收费全文 | 174篇 |
免费 | 4篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 15篇 |
金属工艺 | 2篇 |
机械仪表 | 2篇 |
建筑科学 | 14篇 |
能源动力 | 1篇 |
轻工业 | 17篇 |
无线电 | 10篇 |
一般工业技术 | 9篇 |
冶金工业 | 89篇 |
自动化技术 | 18篇 |
出版年
2024年 | 1篇 |
2022年 | 1篇 |
2021年 | 3篇 |
2020年 | 4篇 |
2019年 | 3篇 |
2018年 | 3篇 |
2017年 | 1篇 |
2016年 | 6篇 |
2013年 | 4篇 |
2012年 | 3篇 |
2011年 | 8篇 |
2010年 | 15篇 |
2009年 | 5篇 |
2008年 | 5篇 |
2007年 | 4篇 |
2006年 | 3篇 |
2005年 | 3篇 |
2004年 | 8篇 |
2003年 | 5篇 |
2002年 | 4篇 |
2001年 | 2篇 |
2000年 | 5篇 |
1999年 | 2篇 |
1998年 | 20篇 |
1997年 | 9篇 |
1996年 | 10篇 |
1995年 | 5篇 |
1994年 | 2篇 |
1993年 | 6篇 |
1992年 | 5篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1983年 | 2篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1976年 | 2篇 |
1972年 | 1篇 |
1966年 | 2篇 |
排序方式: 共有178条查询结果,搜索用时 15 毫秒
1.
2.
GA Storch RS Buller TC Bailey NA Ettinger T Langlois M Gaudreault-Keener PL Welby 《Canadian Metallurgical Quarterly》1994,32(4):997-1003
This study compared PCR and an assay for cytomegalovirus (CMV) pp65 antigenemia (CMV-vue; INCSTAR Corp.) with a quantitative shell vial culture (QSVC) technique for the detection of CMV in serial blood specimens from 46 solid-organ transplant recipients. In a comparison based on 535 specimens tested by PCR and QSVC, CMV was detected by PCR in 41 and by QSVC in 37 of 43 recipients at risk of CMV infection. The mean number of days after transplantation of initial detection of CMV was 29.9 for PCR and 34.0 for QSVC (P = 0.01). The antigenemia assay was performed on 395 specimens, including 304 of those also tested by PCR. In these specimens, CMV was detected by the antigenemia assay, QSVC, and PCR in 30, 32, and 35 (respectively) of 38 patients at risk, with no statistically significant difference in the time to detection. Each of the assays detected CMV in similar proportions of patients with and without clinically significant CMV infection. PCR stayed positive longer after transplantation than the other assays but frequently returned to negative when more than 6 months had elapsed after transplantation. The antigenemia assay and PCR stayed positive longer after institution of antiviral therapy than QSVC. PCR can provide highly sensitive detection of CMV viremia, but a PCR assay for CMV is not yet available in kit form. The pp65 antigenemia assay and shell vial culture are quantifiable and comparable in sensitivity. Either is recommended for rapid detection of CMV in blood specimens from solid-organ transplant recipients. 相似文献
3.
Hannah R. Hall Cressida Mahung Julia L. M. Dunn Laurel M. Kartchner Roland F. Seim Bruce A. Cairns Shannon M. Wallet Robert Maile 《International journal of molecular sciences》2022,23(15)
Severe burn injury leads to a cascade of local and systemic immune responses that trigger an extreme state of immune dysfunction, leaving the patient highly susceptible to acute and chronic infection. When combined with inhalation injury, burn patients have higher mortality and a greater chance of developing secondary respiratory complications including infection. No animal model of combined burn and inhalation injury (B+I) exists that accurately mirrors the human clinical picture, nor are there any effective immunotherapies or predictive models of the risk of immune dysfunction. Our earlier work showed that the mechanistic/mammalian target of rapamycin (mTOR) pathway is activated early after burn injury, and its chemical blockade at injury reduced subsequent chronic bacterial susceptibility. It is unclear if mTOR plays a role in the exacerbated immune dysfunction seen after B+I injury. We aimed to: (1) characterize a novel murine model of B+I injury, and (2) investigate the role of mTOR in the immune response after B+I injury. Pulmonary and systemic immune responses to B+I were characterized in the absence or presence of mTOR inhibition at the time of injury. Data describe a murine model of B+I with inhalation-specific immune phenotypes and implicate mTOR in the acute immune dysfunction observed. 相似文献
4.
GP Kalemkerian M Jiroutek DS Ettinger JA Dorighi DH Johnson M Mabry 《Canadian Metallurgical Quarterly》1998,83(6):1102-1108
BACKGROUND: The dysregulation of both myc gene expression and retinoid signaling pathways commonly occurs in small cell lung carcinoma (SCLC). Because preclinical data showed that all-trans-retinoic acid (RA) inhibited SCLC growth, altered myc expression, and blocked transition to a treatment-resistant phenotype, a Phase II trial was designed to determine the effects of the combination of RA, cisplatin, and etoposide in patients with SCLC. METHODS: Patients with untreated, extensive stage SCLC were treated with up to 8 cycles of cisplatin, 60 mg/m2, intravenously (i.v.) on Day 1 and etoposide, 120 mg/m2, i.v. on Days 1-3 in addition to up to 1 year of oral RA, 150 mg/m2/day. RESULTS: Of 22 assessable patients 1 had a complete response and 9 had a partial response, for an overall response rate of 45% (95% confidence interval, 24-68%). The median survival was 10.9 months and the 1-year survival was 41%. The median duration of chemotherapy was 6 cycles and the median duration of RA treatment was 2.8 months. Thirteen patients discontinued RA prematurely due to toxicity and only 4 responders were receiving RA at the time of recurrence. Toxicity-limiting RA treatment mainly was comprised of mucocutaneous changes and headaches. CONCLUSIONS: RA at a dose of 150 mg/m2/day was tolerated poorly in combination with cisplatin plus etoposide, leading to early discontinuation of RA in the majority of patients. The hematologic toxicity, response rate, and survival were similar to those associated with cisplatin and etoposide in prior trials. Further studies with more active and less toxic agents will be required to determine the role of retinoids in the treatment of SCLC. 相似文献
5.
Three variable microsatellite loci have been isolated from the American lobster, Homarus americanus. In a population sample from the Gulf of Maine, the effective numbers of alleles (Ne) for the two most variable loci were 16.33 and 13.19, respectively. Reduced variability at all three loci was seen in the European lobster, H. gammarus, for which the maximum Ne was 4.00. The reduction in variability in H. gammarus is consistent with a bottleneck event. Inheritance analysis using H. americanus demonstrated segregation of codominant alleles and the absence of linkage. Null alleles were observed at two loci in inheritance studies. This study demonstrates that microsatellite loci should be useful in studying the population structure of clawed lobsters. 相似文献
6.
28 adults and 48 8-mo-old infants listened to repeated transpositions of a 10-note melody exemplifying the rules of Western tonal music. They were tested for their detection of 2 types of changes to that melody: (1) a 4-semitone change in 1 note that remained within the key and implied dominant harmony (diatonic change) or (2) a 1-semitone change in the same note that went outside the key (nondiatonic change). Adults easily detected the nondiatonic change but had difficulty with the diatonic change. Infants detected both changes equally well, performing better than adults in some circumstances. These findings imply that there are qualitative differences in infants' and adults' processing of musical information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
Antivirulence Isoquinolone Mannosides: Optimization of the Biaryl Aglycone for FimH Lectin Binding Affinity and Efficacy in the Treatment of Chronic UTI 下载免费PDF全文
Cassie Jarvis Dr. Zhenfu Han Vasilios Kalas Roger Klein Jerome S. Pinkner Dr. Bradley Ford Jana Binkley Dr. Corinne K. Cusumano Dr. Zachary Cusumano Dr. Laurel Mydock‐McGrane Prof. Scott J. Hultgren Prof. James W. Janetka 《ChemMedChem》2016,11(4):367-373
Uropathogenic E. coli (UPEC) employ the mannose‐binding adhesin FimH to colonize the bladder epithelium during urinary tract infection (UTI). Previously reported FimH antagonists exhibit good potency and efficacy, but low bioavailability and a short half‐life in vivo. In a rational design strategy, we obtained an X‐ray structure of lead mannosides and then designed mannosides with improved drug‐like properties. We show that cyclizing the carboxamide onto the biphenyl B‐ring aglycone of biphenyl mannosides into a fused heterocyclic ring, generates new biaryl mannosides such as isoquinolone 22 (2‐methyl‐4‐(1‐oxo‐1,2‐dihydroisoquinolin‐7‐yl)phenyl α‐d ‐mannopyranoside) with enhanced potency and in vivo efficacy resulting from increased oral bioavailability. N‐Substitution of the isoquinolone aglycone with various functionalities produced a new potent subseries of FimH antagonists. All analogues of the subseries have higher FimH binding affinity than unsubstituted lead 22 , as determined by thermal shift differential scanning fluorimetry assay. Mannosides with pyridyl substitution on the isoquinolone group inhibit bacteria‐mediated hemagglutination and prevent biofilm formation by UPEC with single‐digit nanomolar potency, which is unprecedented for any FimH antagonists or any other antivirulence compounds reported to date. 相似文献
8.
9.
McDonald LA Barbieri LR Carter GT Kruppa G Feng X Lotvin JA Siegel MM 《Analytical chemistry》2003,75(11):2730-2739
The molecular formulas for the structures and substructures of muraymycin antibiotics A1 (C52H90N14O19, MW 1214) and B1 (C49H83N11O18, MW 1113) were determined using electrospray ionization (ESI) Fourier transform mass spectrometry (FTMS). The muraymycin A1 and B1 structures were elucidated by utilizing capillary-skimmer fragmentation with up to five stages of mass spectrometry (MS5). Multi-CHEF, a multiple ion isolation method, was used at each stage of MS(n) to isolate a parent ion and up to four reference ions, for exact-mass calibration. The parent ions were fragmented by SORI-CID and the product ions internally calibrated with average absolute mass errors less than 1 ppm at each stage in the fragmentation processes. Using the top-down/bottom-up approach, the molecular formulas for the antibiotics were determined by summing the elemental formulas of the neutral losses, obtained by measuring the mass differences (<500 Da) between the genetically related sequential parent ion masses in the MS(n) spectra, with the unique elemental formula of the lowest parent ion mass (<500 Da). The structures of 12 additional compounds in the muraymycin complex were elucidated using HPLC ESI capillary-skimmer CID FTMS by correlating their fragmentation patterns with those of muraymycins A1 and B1. Sequential neutral losses of an aminosugar, a valine, a uridine, and an ester fatty acid from the muraymycin parent ions provided diagnostic fragments for characterization. 相似文献
10.
Beyth-Marom Ruth; Austin Laurel; Fischhoff Baruch; Palmgren Claire; Jacobs-Quadrel Marilyn 《Canadian Metallurgical Quarterly》1993,29(3):549
Adult and adolescent Ss were asked to list possible consequences of either accepting or declining opportunities to engage in various potentially risky behaviors (e.g., drinking and driving, skipping school to go to a mall). Response patterns were quite similar for these adults and adolescents, indicating shared beliefs about the possibilities. Although taking and avoiding a risk are logically complementary actions, they did not prove to be psychologically complementary. Other comparisons showed systematic differences in the consequences produced for 1-time and regular (or repeated) versions of the same behaviors, as well as open-ended and closed-ended response modes. These results are discussed in terms of their methodological implications for studying risk perceptions, their practical implications for influencing adolescents' risk behaviors, and their theoretical implications for understanding intellectual development. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献