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181.
Agnieszka Czylkowska Bartomiej Rogalewicz Magorzata Szczesio Anita Raducka Katarzyna Gobis Pawe Szymaski Kamila Czarnecka Bruno Cury Camargo Jacek Szczytko Alexey Babich Sergey Dubkov Petr Lazarenko 《International journal of molecular sciences》2022,23(6)
A novel biologically active organic ligand L (N’-benzylidenepyrazine-2-carbohydrazonamide) and its three coordination compounds have been synthesized and structurally described. Their physicochemical and biological properties have been thoroughly studied. Cu(II), Zn(II), and Cd(II) complexes have been analyzed by F-AAS spectrometry and elemental analysis. The way of metal–ligand coordination was discussed based on FTIR spectroscopy and UV-VIS-NIR spectrophotometry. The thermal behavior of investigated compounds was studied in the temperature range 25–800 °C. All compounds are stable at room temperature. The complexes decompose in several stages. Magnetic studies revealed strong antiferromagnetic interaction. Their cytotoxic activity against A549 lung cancer cells have been studied with promising results. We have also investigated the biological effect of coating studied complexes with silver nanoparticles. The morphology of the surface was studied using SEM imaging. 相似文献
182.
Joanna Depciuch Justyna Miszczyk Alexey Maximenko Piotr M. Zielinski Kamila Rawoj Agnieszka Panek Pawel Olko Magdalena Parlinska-Wojtan 《International journal of molecular sciences》2020,21(23)
Herein, we propose newly designed and synthesized gold nanopeanuts (Au NPes) as supports for cisplatin (cPt) immobilization, dedicated to combined glioblastoma nano-chemo-radiotherapy. Au NPes offer a large active surface, which can be used for drugs immobilization. Transmission electron microscopy (TEM) revealed that the size of the synthesized Au NPes along the longitudinal axis is ~60 nm, while along the transverse axis ~20 nm. Raman, thermogravimetric analysis (TGA) and differential scanning calorimetry (DCS) measurements showed, that the created nanosystem is stable up to a temperature of 110 °C. MTT assay revealed, that the highest cell mortality was observed for cell lines subjected to nano-chemo-radiotherapy (20–55%). Hence, Au NPes with immobilized cPt (cPt@AuNPes) are a promising nanosystem to improve the therapeutic efficiency of combined nano-chemo-radiotherapy. 相似文献
183.
Natalia Wojciechowska Shirin Alipour Ewelina Stolarska Karolina Bilska Pascal Rey Ewa M. Kalemba 《International journal of molecular sciences》2020,21(23)
The levels of methionine sulfoxide (MetO) and the abundances of methionine sulfoxide reductases (Msrs) were reported as important for the desiccation tolerance of Acer seeds. To determine whether the MetO/Msrs system is related to reactive oxygen species (ROS) and involved in the regulation of germination in orthodox and recalcitrant seeds, Norway maple and sycamore were investigated. Changes in water content, MetO content, the abundance of MsrB1 and MsrB2 in relation to ROS content and the activity of reductases depending on nicotinamide adenine dinucleotides were monitored. Acer seeds differed in germination speed—substantially higher in sycamore—hydration dynamics, levels of hydrogen peroxide, superoxide anion radicals (O2•−) and hydroxyl radicals (•OH), which exhibited peaks at different stages of germination. The MetO level dynamically changed, particularly in sycamore embryonic axes, where it was positively correlated with the levels of O2•− and the abundance of MsrB1 and negatively with the levels of •OH and the abundance of MsrB2. The MsrB2 abundance increased upon sycamore germination; in contrast, it markedly decreased in Norway maple. We propose that the ROS–MetO–Msr redox system, allowing balanced Met redox homeostasis, participates in the germination process in sycamore, which is characterized by a much higher speed compared to Norway maple. 相似文献
184.
Patrycja Paluszkiewicz Adrian Martuszewski Natalia Zarba Kamila Wala Mirosaw Banasik Marta Kepinska 《International journal of molecular sciences》2022,23(1)
Nanomedicine is currently showing great promise for new methods of diagnosing and treating many diseases, particularly in kidney disease and transplantation. The unique properties of nanoparticles arise from the diversity of size effects, used to design targeted nanoparticles for specific cells or tissues, taking renal clearance and tubular secretion mechanisms into account. The design of surface particles on nanoparticles offers a wide range of possibilities, among which antibodies play an important role. Nanoparticles find applications in encapsulated drug delivery systems containing immunosuppressants and other drugs, in imaging, gene therapies and many other branches of medicine. They have the potential to revolutionize kidney transplantation by reducing and preventing ischemia–reperfusion injury, more efficiently delivering drugs to the graft site while avoiding systemic effects, accurately localizing and visualising the diseased site and enabling continuous monitoring of graft function. So far, there are known nanoparticles with no toxic effects on human tissue, although further studies are still needed to confirm their safety. 相似文献
185.
186.
Kamila Rzd Ewa Paluszkiewicz Damian Neubauer Mateusz Olszewski Katarzyna Kozowska-Tylingo Wojciech Kamysz Iwona Gabriel 《International journal of molecular sciences》2021,22(24)
Acridine cell-penetrating peptide conjugates are an extremely important family of compounds in antitumor chemotherapy. These conjugates are not so widely analysed in antimicrobial therapy, although bioactive peptides could be used as nanocarriers to smuggle antimicrobial compounds. An octaarginine conjugate of an imidazoacridinone derivative (Compound 1-R8) synthetized by us exhibited high antifungal activity against reference and fluconazole-resistant clinical strains (MICs ≤ 4 μg mL−1). Our results clearly demonstrate the qualitative difference in accumulation of the mother compound and Compound 1-R8 conjugate into fungal cells. Only the latter was transported and accumulated effectively. Microscopic and flow cytometry analysis provide some evidence that the killing activity of Compound 1-R8 may be associated with a change in the permeability of the fungal cell membrane. The conjugate exhibited low cytotoxicity against human embryonic kidney (HEK-293) and human liver (HEPG2) cancer cell lines. Nevertheless, the selectivity index value of the conjugate for human pathogenic strains remained favourable and no hemolytic activity was observed. The inhibitory effect of the analysed compound on yeast topoisomerase II activity suggested its molecular target. In summary, conjugation with R8 effectively increased imidazoacridinone derivative ability to enter the fungal cell and achieve a concentration inside the cell that resulted in a high antifungal effect. 相似文献
187.
Kamila Dilimulati Misaki Orita Yoshiki Yonahara Fabiana Lica Imai Naoto Yonezawa 《International journal of molecular sciences》2022,23(2)
The species-selective interaction between sperm and egg at the beginning of mammalian fertilisation is partly mediated by a transparent envelope called the zona pellucida (ZP). The ZP is composed of three or four glycoproteins (ZP1–ZP4). The functions of the three proteins present in mice (ZP1–ZP3) have been extensively studied. However, the biological role of ZP4, which was found in all other mammals studied so far, has remained largely unknown. Previously, by developing a solid support assay system, we showed that ZP4 exhibits sperm-binding activity in bovines and the N-terminal domain of bovine ZP4 (bZP4 ZP-N1 domain) is a sperm-binding region. Here, we show that bovine sperm bind to the bZP4 ZP-N1 domain in a species-selective manner and that N-glycosylation is not required for sperm-binding activity. Moreover, we identified three sites involved in sperm binding (site I: from Gln-41 to Pro-46, site II: from Leu-65 to Ser-68 and site III: from Thr-108 to Ile-123) in the bZP4 ZP-N1 domain using chimeric bovine/porcine and bovine/human ZP4 recombinant proteins. These results provide in vitro experimental evidence for the role of the bZP4 ZP-N1 domain in mediating sperm binding to the ZP. 相似文献
188.
Bania J Dabrowska A Bystron J Korzekwa K Chrzanowska J Molenda J 《International journal of food microbiology》2006,108(1):36-41
Extensive analysis of the Staphylococcus aureus genome has allowed the identification of new genes encoding enterotoxin-like superantigens (SEls). Some of these are thought to be involved in staphylococcal food poisoning, while others do not elicit any emetic effect. The potential impact of these members of the enterotoxin-like family on the human organism seems to rely mainly on their superantigenic activity. In this paper the distribution of the genes coding for enterotoxin-like superantigens in S. aureus isolated from food was studied. Fifty isolates of S. aureus were examined and 27 were shown to be enterotoxigenic. Only 9 of the 27 strains carried genes encoding enterotoxins SEA-SEE. In 18 SEA-SEE-negative strains the presence of newly described enterotoxin genes was detected. All SEA-SEE-positive strains simultaneously carried genes of new SEls. We show that the gene encoding SElH (staphylococcal enterotoxin-like enterotoxin H) was the most frequently detected (n=14), while genes encoding SElI together with SElG accompanied by the other genes of the egc locus were detected in three strains. We also detected the presence of three less investigated genes: sep, sel, and sek. These genes were present in eight, two, and one isolate, respectively. In one strain, sep was accompanied by genes of other SEls, while in the remaining seven it was the only enterotoxin-like gene detected. The high prevalence of newly discovered enterotoxin genes, including the genes encoding emetic toxins, was demonstrated in food-derived strains. This supports the need for additional work on its role in food poisoning and, alternatively, to monitor its presence in S. aureus isolated from food. Our results suggest that yet unknown genetic elements encoding enterotoxin genes may exist. 相似文献
189.
Structure and catalytic activity of double copper–manganese oxide catalysts supported on MgF2 and Al2O3 have been studied. All samples were calcined at 400 °C and those supported on Al2O3 also at 550 and 950 °C. The properties of surface species have been characterized by low temperature adsorption of nitrogen,
XRD and TPR-H2. The catalytic activities have been tested in low-temperature CO oxidation and in NO reduction by propene. The supported
oxides react with each other during calcination to form CuMn2O4 spinel. The spinel seems to be responsible for the catalytic activity of the double copper–manganese catalysts. The temperature
of calcination changes the strength of interaction between the active phase and the supports influencing the catalytic activity. 相似文献
190.
Maria Wojciechowska Mariusz Pietrowski Bogdan Czajka Sławomir Łomnicki 《Catalysis Letters》2003,85(3-4):153-157
The effect of water and reductants (CO and H2) on the decomposition of NO
x
stored on BaO/Al2O3 at 300 °C has been investigated. Water eliminates the initial rapid total uptake of NO2 but has little effect on the subsequent formation of nitrates that is accompanied by evolution of NO. Water hinders liberation of NO2 and NO during temperature-programmed decomposition of stored NO
x
. Both CO and H2 lower the temperatures required for decomposition through reduction of NO2 to NO and N2 thus restricting NO2 readsorption. The rate of reduction is lower with H2 than with CO. 相似文献