全文获取类型
收费全文 | 92篇 |
免费 | 3篇 |
专业分类
化学工业 | 17篇 |
机械仪表 | 1篇 |
建筑科学 | 10篇 |
矿业工程 | 1篇 |
能源动力 | 2篇 |
轻工业 | 19篇 |
水利工程 | 1篇 |
无线电 | 15篇 |
一般工业技术 | 11篇 |
冶金工业 | 6篇 |
自动化技术 | 12篇 |
出版年
2023年 | 2篇 |
2022年 | 7篇 |
2021年 | 3篇 |
2019年 | 3篇 |
2017年 | 2篇 |
2016年 | 1篇 |
2015年 | 2篇 |
2014年 | 8篇 |
2013年 | 10篇 |
2012年 | 6篇 |
2011年 | 4篇 |
2010年 | 5篇 |
2009年 | 6篇 |
2008年 | 8篇 |
2007年 | 8篇 |
2006年 | 4篇 |
2005年 | 4篇 |
2003年 | 4篇 |
2002年 | 1篇 |
2000年 | 1篇 |
1999年 | 3篇 |
1996年 | 2篇 |
1992年 | 1篇 |
排序方式: 共有95条查询结果,搜索用时 148 毫秒
51.
52.
Jeffrey W. Schubert Dr. Scott T. Harrison James Mulhearn Robert Gomez Robert Tynebor Kristen Jones Jaime Bunda Barbara Hanney Jenny Miu-Chen Wai Dr. Chris Cox Dr. John A. McCauley Dr. John M. Sanders Brian Magliaro Julie O'Brien Dr. Natasa Pajkovic Sarah L. Huszar Agrapides Anne Taylor Dr. Anthony Gotter Dr. Sean M. Smith Dr. Jason Uslaner Dr. Susan Browne Dr. Stefania Risso Dr. Melissa Egbertson 《ChemMedChem》2019,14(9):943-951
Herein we describe the discovery and optimization of a new series of 2,3-disubstituted and 2,3,6-trisubstituted muscarinic acetylcholine receptor 4 (M4) positive allosteric modulators (PAMs). Iterative libraries enabled rapid exploration of one-dimensional structure–activity relationships (SAR) and identification of potency-enhancing heterocycle and N-alkyl pyrazole substituents. Further optimization led to identification of the potent, receptor-subtype-selective, brain-penetrant tool compound 24 (7-[3-[1-[(1-fluorocyclopentyl)methyl]pyrazol-4-yl]-6-methyl-2-pyridyl]-3-methoxycinnoline). It is efficacious in preclinical assays that are predictive of antipsychotic effects, producing dose-dependent reversal of amphetamine-induced hyperlocomotion in rats and mice, but not in M4 knockout mice. Cholinergic-related adverse effects observed in rats treated with 24 at unbound plasma concentrations more than 3-fold higher than an efficacious dose in the hyperlocomotion assay were fewer and less severe than those observed in rats treated with the nonselective M4 agonist xanomeline, suggesting a receptor-subtype-selective PAM has the potential for an improved safety profile. 相似文献
53.
Dewey G. Hudait M.K. Kangho Lee Pillarisetty R. Rachmady W. Radosavljevic M. Rakshit T. Chau R. 《Electron Device Letters, IEEE》2008,29(10):1094-1097
DC and high-frequency device characteristics of In0.7Ga0.3As and InSb quantum-well field-effect transistors (QWFETs) are measured and benchmarked against state-of- the-art strained silicon (Si) nMOSFET devices, all measured on the same test bench. Saturation current (Ion) gam of 20% is observed in the In0.7Ga0.3As QWFET over the strained Si nMOSFET at (Vg - Vt) = 0.3 V, Vds = 0.5 V, and matched Ioff, despite higher external resistance and large gate-to-channel thickness. To understand the gain in Ion, the effective carrier velocities (veff) near the source-end are extracted and it is observed that at constant (Vg - Vt) = 0.3 V and Vds = 0.5 V, the veff of In0.7Ga0.3As and InSb QWFETs are 4-5times higher than that of strained silicon (Si) nMOSFETs due to the lower effective carrier mass in the QWFETs. The product of veff and charge density (ns), which is a measure of "intrinsic" device characteristics, for the QWFETs is 50%-70% higher than strained Si at low-voltage operation despite lower ns in QWFETs. Calibrated simulations of In0.7Ga0.3As QWFETs with reduced gate-to-channel thickness and external resistance matched to the strained Si nMOSFET suggest that the higher veff will result in more than 80% Ion increase over strained Si nMOSFETs at Vds = 0.5 V, (Vg - Vt) = 0.3 V, and matched Ioff, thus showing promise for future high-speed and low-power logic applications. 相似文献
54.
Quantitative analysis of lycopene isomers in human plasma using high-performance liquid chromatography-tandem mass spectrometry 总被引:2,自引:0,他引:2
An analytical method for the determination of the concentrations of total lycopene and its cis and all-trans isomers in human plasma has been developed using high-performance liquid chromatography-tandem mass spectrometry (LC-MS-MS). This method was based on the observation that, during negative ion atmospheric pressure chemical ionization with collision-induced dissociation, a unique fragment of m/z 467 was formed from the molecular ion of m/z 536 by elimination of a terminal isoprene group. The use of multiple reaction monitoring facilitated the selective detection of lycopene isomers and an internal standard without interference from the isobaric carotenoids a-carotene and beta-carotene, which are also abundant in human plasma. Measurement of total lycopene was carried out using a C18 high-performance liquid chromatography (HPLC) column and an isocratic mobile phase consisting of acetonitrile/methyl tert-butyl ether (95:5) so that all lycopene isomers eluted as a single chromatographic peak. all-trans-Lycopene was separated from its various cis isomers by using a C30 carotenoid column and a gradient solvent system from methanol to methyl tert-butyl ether. The effects of sample preparation and handling parameters on the stability of lycopene were evaluated such as the stability of lycopene in the HPLC autosampler and the effect of saponification upon lycopene isomerization. For example, the half-life of all-trans-lycopene in the HPLC mobile phase in the autosampler at 4 degrees C was determined to be approximately 16 h. Also, saponification of plasma samples was determined to cause lycopene degradation and isomerization so that lycopene recovery was reduced. The accuracy and interassay precision of this LC-MS-MS assay for lycopene showed a standard deviation of less than 10% over the range of 5-500 pmol injected on-column. The limit of detection was 11.2 fmol injected on-column, and the limit of quantitation was 22.8 fmol. 相似文献
55.
Marija Stankovic Katarina Veljovic Nikola Popovic Snezana Kojic Sofija Dunjic Manevski Dragica Radojkovic Natasa Golic 《International journal of molecular sciences》2022,23(10)
Bronchial epithelial cells are exposed to environmental influences, microbiota, and pathogens and also serve as a powerful effector that initiate and propagate inflammation by the release of pro-inflammatory mediators. Recent studies suggested that lung microbiota differ between inflammatory lung diseases and healthy lungs implicating their contribution in the modulation of lung immunity. Lactic acid bacteria (LAB) are natural inhabitants of healthy human lungs and also possess immunomodulatory effects, but so far, there are no studies investigating their anti-inflammatory potential in respiratory cells. In this study, we investigated immunomodulatory features of 21 natural LAB strains in lipopolysaccharide (LPS)-stimulated human bronchial epithelial cells (BEAS-2B). Our results show that several LAB strains reduced the expression of pro-inflammatory cytokine and chemokine genes. We also demonstrated that two LAB strains, Lactobacillus brevis BGZLS10-17 and Lb. plantarum BGPKM22, effectively attenuated LPS-induced nuclear factor-κB (NF-κB) nuclear translocation. Moreover, BGZLS10-17 and BGPKM22 reduced the activation of p38, extracellular signal-related kinase (ERK), and c-Jun amino-terminal kinase (JNK) signaling cascade resulting in a reduction of pro-inflammatory mediator expressions in BEAS-2B cells. Collectively, the LAB strains BGZLS10-17 and BGPKM22 exhibited anti-inflammatory effects in BEAS-2B cells and could be employed to balance immune response in lungs and replenish diminished lung microbiota in chronic lung diseases. 相似文献
56.
57.
Dino Jordanoski Damjana Drobne Nea Repar Iztok Dogsa Polona Mrak Romana Cerc-Koroec Andrijana Sever kapin Peter Nadrah Natasa Poklar Ulrih 《International journal of molecular sciences》2022,23(13)
Tetraethyl-orthosilicate (TEOS)-based nanoparticles are most extensively used as a silica-based hemoglobin carrier system. However, TEOS-based nanoparticles induce adverse effects on the hemoglobin structure. Therefore, a heulandite-calcium-based carrier was investigated as a novel silica-based hemoglobin carrier system. The heulandite-calcium mesoporous aluminosilicate particles (MSPs) were fabricated by a patented tribo-mechanical activation process, according to the manufacturer, and its structure was assessed by X-ray diffraction analysis. Upon hemoglobin encapsulation, alternation in the secondary and tertiary structure was observed. The hemoglobin-particle interactions do not cause heme degradation or decreased activity. Once encapsulated inside the particle pores, the hemoglobin shows increased thermal stability, and higher loading capacity per gram of particles (by a factor of >1.4) when compared to TEOS-based nanoparticles. Futhermore, we introduced a PEGlyted lipid bilayer which significantly decreases the premature hemoglobin release and increases the colloidal stability. The newly developed hemoglobin carrier shows no cytotoxicity to human umbilical vein endothelial cells (HUVEC). 相似文献
58.
Zana Besser Silconi Vesna Rosic Sasa Benazic Gordana Radosavljevic Marina Mijajlovic Jelena Pantic Zoran R. Ratkovic Gordana Radic Aleksandar Arsenijevic Marija Milovanovic Nebojsa Arsenijevic Jelena Milovanovic 《International journal of molecular sciences》2022,23(15)
B cell malignancies are, despite the development of targeted therapy in a certain percentage of the patients still a chronic disease with relapses, requiring multiple lines of therapy. Regimens that include platinum-based drugs provide high response rates in different B cell lymphomas, high-risk chronic lymphocytic leukemia (CLL), and devastating complication of CLL, Richter’s syndrome. The aim of this study was to explore the potential antitumor activity of previously synthetized platinum(IV) complex with alkyl derivatives of thyosalicilc acid, PtCl2(S-pr-thiosal)2, toward murine BCL1 cells and to delineate possible mechanisms of action. The PtCl2(S-pr-thiosal)2 reduced the viability of BCL1 cells in vitro but also reduced the growth of metastases in the leukemia lymphoma model in BALB/c mice. PtCl2(S-pr-thiosal)2 induced apoptosis, inhibited proliferation of BCL1 cells, and induced cell cycle disturbance. Treatment of BCL1 cells with PtCl2(S-pr-thiosal)2 inhibited expression of cyclin D3 and cyclin E and enhanced expression of cyclin-dependent kinase inhibitors p16, p21, and p27 resulting in cell cycle arrest in the G1 phase, reduced the percentage of BCL1 cells in the S phase, and decreased expression of Ki-67. PtCl2(S-pr-thiosal)2 treatment reduced expression of phosphorylated STAT3 and downstream-regulated molecules associated with cancer stemness and proliferation, NANOG, cyclin D3, and c-Myc, and expression of phosphorylated NFκB in vitro and in vivo. In conclusion, PtCl2(S-pr-thiosal)2 reduces STAT3 and NFκB phosphorylation resulting in inhibition of BCL1 cell proliferation and the triggering of apoptotic cell death. 相似文献
59.
Natasa P. Kalogiouri Lambros E. Kokokiris Stephania Doulgeraki Athanasios N. Papadopoulos Victoria F. Samanidou 《International Journal of Food Science & Technology》2021,56(8):4091-4097
Canned tuna was fortified with a mixture of brine and hydrosols of aromatic plants (i.e. oregano, laurel, sage and lemon balm). An HPLC-DAD method was developed and validated for the simultaneous determination of thirteen antioxidants in tuna fillets, including phenolic acids (gallic acid, vanillic acid, syringic acid and rosmarinic acid), flavonoids (catechin, epicatechin, vanillin, myricetin, rutin, quercetin, luteolin and apigenin) and one hydroxybenzaldehyde (syringaldehyde). The analytes showed satisfying recovery efficiency (82.1–92.1%), and the method presented excellent linearity (r2 > 0.99). The precision limit was ≤5.6% RSDr for intra-day and ≤7.2% RSDR for inter-day experiments. The determined analytes ranged between 8.86 mg (quercetin) and 512 mg (rosmarinic acid) per 100g tuna flesh (n = 10), verifying that the hydrosols fortified the tuna fillets. 相似文献
60.
Shinya Kikuchi Natasa Vukadinović Said M. Easa 《Civil Engineering and Environmental Systems》2013,30(3):134-144
The fuzzy linear programming (FLP) transportation problem is a useful tool for some civil engineering problems. It can deal with problems whose objective and constraints are not well-defined, or information on them is not precise. It considers that the objective and constraints are fuzzy sets in the space of alternatives and defines the decision set as the intersection of the two sets. The solution is the element of the decision set which has the maximum membership grade. This paper addresses the type of problems which are suited for fuzzy LP transportation modeling; examines the formulation of the model and characteristics of the solution; and presents an example of FLP transportation formulation for the earth moving problem during highway construction. The solution's sensitivity to the fuzziness of objective and information on the quantities of supply and demand is also analysed. 相似文献