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151.
Ewa M. Nowosielska Aneta Cheda Mateusz Pociegiel Lukasz Cheda Pawe Szymaski Antoni Wiedlocha 《International journal of molecular sciences》2021,22(12)
Non-small cell lung cancer (NSCLC) continues to be the leading cause of cancer death worldwide. Recently, targeting molecules whose functions are associated with tumorigenesis has become a game changing adjunct to standard anti-cancer therapy. As evidenced by the results of preclinical and clinical investigations, whole-body irradiations (WBI) with X-rays at less than 0.1–0.2 Gy per fraction can induce remissions of various neoplasms without inciting adverse side effects of conventional chemo- and radiotherapy. In the present study, a murine model of human NSCLC was employed to evaluate for the first time the anti-neoplastic efficacy of WBI combined with inactivation of CTLA-4, PD-1, and/or HSP90. The results indicate that WBI alone and in conjunction with the inhibition of the function of the cytotoxic T-lymphocyte antigen-4 (CTLA-4) and the programmed death-1 (PD-1) receptor immune checkpoints (ICs) and/or heat shock protein 90 (HSP90) markedly reduced tumorigenesis in mice implanted by three different routes with the syngeneic Lewis lung cancer cells and suppressed clonogenic potential of Lewis lung carcinoma (LLC1) cells in vitro. These results were associated with the relevant changes in the profile of pro- and anti-neoplastic immune cells recruited to the growing tumors and the circulating anti- and pro-inflammatory cytokines. In contrast, inhibition of the tested molecular targets used either separately or in combination with each other did not exert notable anti-neoplastic effects. Moreover, no significant synergistic effects were detected when the inhibitors were applied concurrently with WBI. The obtained results supplemented with further mechanistic explanations provided by future investigations will help design the effective strategies of treatment of lung and other cancers based on inactivation of the immune checkpoint and/or heat shock molecules combined with low-dose radiotherapy. 相似文献
152.
Wojciech Radzki Marta Ziaja-Sołtys Jakub Nowak Jolanta Topolska Anna Bogucka-Kocka Aneta Sławińska Monika Michalak-Majewska Ewa Jabłońska-Ryś Andrzej Kuczumow 《International Journal of Food Science & Technology》2019,54(4):1405-1412
Agaricus bisporus fruiting bodies were subjected to processing: blanching, boiling in water and blanching followed by lactic acid fermentation. Water soluble polysaccharides were obtained from fruiting bodies, quantified and analysed in terms of chemical composition, antioxidant capacity and antiproliferative activity towards cancer cell lines (MCF-7 and T-47D). The content of water soluble polysaccharides ranged from 7.35 ± 0.12 to 6.90 ± 0.17 mg g−1 fresh weight of sample. Boiling in water and blanching followed by fermenting caused minor decrease in the content. Fourier Transform Infrared spectroscopy of the extracted polysaccharides showed that both α- and β-linkages are present in the samples. Size exclusion chromatography confirmed the presence of 163.3 and 1.9 kDa molecules. The processing caused changes in chemical composition (protein and phenolics content decreased). The isolated polysaccharides exerted antioxidant and antiproliferative activities. Both the activities were slightly lowered as the result of the processing. 相似文献
153.
154.
Edyta Kordialik-Bogacka Paulina Bogdan Aneta Ciosek 《International Journal of Food Science & Technology》2019,54(5):1706-1712
Pseudocereals such as quinoa and amaranth can be used as partial replacements for malt in the production of new beers. Quinoa and amaranth are of interest due to their high levels of nutrients and micronutrients, including minerals which can significantly improve the performance of brewing yeast and the fermentation rate. In this study, we investigated whether the use of quinoa or amaranth as partial replacements for malt affected the concentration of ions such as zinc and magnesium in beer wort. The use of amaranth, and in particular quinoa, increased the content of both zinc and magnesium ions substantially, even when only 10% of the barley malt was replaced. With 10% quinoa, Zn2+ and Mg2+ content increased by 41% and 49%, respectively, while the ratio of Mg2+ to Ca2+ rose from 1.4:1 to 1.9:1. Use of unmalted quinoa and amaranth appears a good way of enriching wort with essential metal ions. 相似文献
155.
156.
Tobias Heck Dipl. Biol. Artur Reimer Dieter Seebach Prof. Dr. James Gardiner Dr. Gildas Deniau Dr. Aneta Lukaszuk Dr. Hans‐Peter E. Kohler Dr. Birgit Geueke Dr. 《Chembiochem : a European journal of chemical biology》2010,11(8):1129-1136
We have previously shown that the β‐aminopeptidases BapA from Sphingosinicella xenopeptidilytica and DmpA from Ochrobactrum anthropi can catalyze reactions with non‐natural β3‐peptides and β3‐amino acid amides. Here we report that these exceptional enzymes are also able to utilize synthetic dipeptides with N‐terminal β2‐amino acid residues as substrates under aqueous conditions. The suitability of a β2‐peptide as a substrate for BapA or DmpA was strongly dependent on the size of the Cα substituent of the N‐terminal β2‐amino acid. BapA was shown to convert a diastereomeric mixture of the β2‐peptide H‐β2hPhe‐β2hAla‐OH, but did not act on diastereomerically pure β2,β3‐dipeptides containing an N‐terminal β2‐homoalanine. In contrast, DmpA was only active with the latter dipeptides as substrates. BapA‐catalyzed transformation of the diastereomeric mixture of H‐β2hPhe‐β2hAla‐OH proceeded along two highly S‐enantioselective reaction routes, one leading to substrate hydrolysis and the other to the synthesis of coupling products. The synthetic route predominated even at neutral pH. A rise in pH of three log units shifted the synthesis‐to‐hydrolysis ratio (vS/vH) further towards peptide formation. Because the equilibrium of the reaction lies on the side of hydrolysis, prolonged incubation resulted in the cleavage of all peptides that carried an N‐terminal β‐amino acid of S configuration. After completion of the enzymatic reaction, only the S enantiomer of β2‐homophenylalanine was detected (ee>99 % for H‐(S)‐β2‐hPhe‐OH, E>500); this confirmed the high enantioselectivity of the reaction. Our findings suggest interesting new applications of the enzymes BapA and DmpA for the production of enantiopure β2‐amino acids and the enantioselective coupling of N‐terminal β2‐amino acids to peptides. 相似文献
157.
158.
The stability of phenolic compounds of three strawberry cultivars was evaluated for changes during prefreezing treatments, storage and various freezing and thawing conditions. Polyphenol content was determined by HPLC-DAD-FL. The sum of assayed polyphenolic (proanthocyanidin and monomeric flavan-3-ols, anthocyanins, ellagic acid, p-coumaric acid) represented 2858.4 mg/kg in Kent, 2893.1 mg/kg in Elkat, and 2438.0 mg/kg in Senga Sengana. After freezing, 4.5-33.6% of polyphenols were lost; protective effects of prefreezing treatments were seen on anthocyanidins and proanthocyanidins: ascorbic acid was the most effective pretreatment, allowing retention of 3.9-27.5% of anthocyanins, and almost total recovery (3.9-23.9%) when associated with liquid nitrogen freezing. Pectin and sugar only allowed retention of 3.0-25.1% and 5.5-25.4% of the antocyanins, respectively. Thawing of the strawberries in a microwave oven (instead of 20 h at 20 °C) had a further positive effect on retention of anthocyanins, proanthocyanins, (+)-catechin and ellagic acid. 相似文献
159.
Aneta Jastrzębska 《European Food Research and Technology》2012,235(3):563-572
The selected biogenic amines, BAs (putrescine, cadaverine, histamine, tyramine, spermidine and spermine), in pork, beef, and poultry meat samples were determined by two simple procedures without derivatization using isotachophoretic technique. Two electrolyte systems were proposed for their separation and determination with satisfactory separation parameters. The linearity of the proposed procedures was between 2–10 mg L?1 and 5–50 or 10–60 mg L?1, whereas average recoveries for the standard solutions of amines and their mixture varied between 99–100 % and 95–105 %, respectively. Average recoveries for standard addition method (96–99 %) indicated satisfactory accuracy of proposed electrolyte systems. The obtained coefficient of variation values for standard solutions and meat samples ranged from 0.62 to 4.54 % and from 0.56 to 6.03 %, respectively, which confirmed good repeatability. Except for spermidine and spermine, BAs levels in fresh meat samples were generally low. The effect of storage time on the content of biogenic amines in meat was also studied indicating the increase of BAs levels (excluding Spermine and Spermidine). 相似文献