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41.
Carl Krüger Janine C. Sekutowski Heinz Hoberg Reinhild Krause-Göing 《Journal of organometallic chemistry》1977,141(2):141-148
The molecular conformations of a (pentaphenyl)aluminacyclopentadiene ligand (I) and its complex with 1,5-cycloactadienenickel (II) have been determined from single crystal X-ray data collected at room temperature with counter methods. The free ligand crystallizes in the monoclinic space group Cc with 4 molecules in a unit cell of dimensions a 10.5598(5), b 22.7089(12), c 13.3417(4) Å, β 98.064(3)°; its (COD)Ni complex Crystallizes in the monoclinic space group P21/n with 4 molecules in a unit cell of the dimensions a 11.9948(8), b 16.9758 (13), c 18.7721(14) Å. β 97.958(3)°. Both structures have been refined anisotropically to R values of 0.0577 and 0.0493, respectively. Upon complexation of I to the nickel atom the planarity of the ring system is distorted, with the aluminum being bent away from the nickel. A direct metal—metal interaction in II (NiAl: 2.748(1) Å) cannot be ruled out. 相似文献
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43.
Janine Dupre-Maquaire 《Journal of Molecular Spectroscopy》1983,101(2):319-324
A new analysis of the ν5 band of 12CD3H is presented using the ground state constants that were determined from the three fundamentals ν3, ν5, and ν6. New lines are assigned and the fit based on 1169 observed transitions including J′ and K′ values up to 23 leads to a set of 16 spectroscopic constants for v5 = 1, allowing the reproduction of experimental wavenumbers with a standard deviation of 0.0047 cm?1. 相似文献
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46.
High-content analysis in preclinical drug discovery 总被引:1,自引:0,他引:1
Denner P Schmalowsky J Prechtl S 《Combinatorial chemistry & high throughput screening》2008,11(3):216-230
High-Content Analysis (HCA) has developed into an established tool and is used in a wide range of academic laboratories and pharmaceutical research groups. HCA is now routinely proving to be effective in providing functionally relevant results. It is essential to select the appropriate HCA application with regard to the targeted compound's cellular function. The cellular impact and compound specificity as revealed by HCA analysis facilitates reaching definitive conclusions at an early stage in the drug discovery process. This technology therefore has the potential to substantially improve the efficiency of pharmaceutical research. Recent advances in fluorescent probes have significantly boosted the success of HCA. Auto-fluorescent proteins which minimally hinder the functioning of the living cell have been playing a decisive role in cell biology research. For companies the severely restricted license conditions regarding auto-fluorescent proteins hamper their general use in pharmaceutical research. This has opened the field for other solutions such as self-labeling protein technology, which could potentially replace the well established methods that utilize auto-fluorescent proteins. In addition, direct labeling techniques have improved considerably and may supersede many of the approaches based on fusion proteins. Following sample preparation, treated cells are imaged and the resulting multiple fluorescent signals are subjected to contextual and statistical analysis. The extraordinary advantage of HCA is that it enables the large-scale and simultaneous quantification and correlation of multiple phenotypic responses and physiological reactions using sophisticated software solutions that permit assay-specific image analysis. Hence, HCA once more has demonstrated its outstanding potential to significantly support establishing effective pharmaceutical research processes in order to both advance research projects and cut costs. 相似文献
47.
[2,3]-Wittig rearrangements of (E)-3-aza-allylic alcohol derivatives can provide access to syn or anti optically enriched 1,2-aminoalcohols by using a chirality transfer or a chiral auxiliary. 相似文献
48.
Janine Wolf Camino M. González Tanarro Michael Gütschow Joachim Sieler Bärbel Schulze 《Helvetica chimica acta》2008,91(1):35-45
The synthesis of novel triaryl‐substituted 4‐(isothiazol‐3‐yl)morpholines 7 and 8 , and 1‐(isothiazol‐3‐yl)piperazines 9 – 13 by reaction of the corresponding isothiazolium salts 5 and 6 with secondary amines in the presence of t‐BuOK in absolute THF is described. Some representatives of the isothiazoles were evaluated as inhibitors of acetylcholinesterase from Electrophorus electricus. 相似文献
49.
Janine N. Boodram Iain J. Mcgregor Peter M. Bruno Paul B. Cressey Dr. Michael T. Hemann Dr. Kogularamanan Suntharalingam 《Angewandte Chemie (International ed. in English)》2016,55(8):2845-2850
The breast cancer stem cell (CSC) potency of a series of copper(II)–phenanthroline complexes containing the nonsteroidal anti‐inflammatory drug (NSAID), indomethacin, is reported. The most effective copper(II) complex in this series, 4 , selectivity kills breast CSC‐enriched HMLER‐shEcad cells over breast CSC‐depleted HMLER cells. Furthermore, 4 reduces the formation, size, and viability of mammospheres, to a greater extent than salinomycin, a potassium ionophore known to selectively inhibit CSCs. Mechanistic studies revealed that the CSC‐specificity observed for 4 arises from its ability to generate intracellular reactive oxygen species (ROS) and inhibit cyclooxygenase‐2 (COX‐2), an enzyme that is overexpressed in breast CSCs. The former induces DNA damage, activates JNK and p38 pathways, and leads to apoptosis. 相似文献
50.
[structure: see text] Hsp90 has recently emerged as a promising biological target for treatment of cancer. Herbimycin A and other members of the benzoquinoid ansamycin class of natural products are known to inhibit Hsp90 activity. The total synthesis of herbimycin A was achieved from the commercially available Roche ester 1 by using allylmetals to control the stereogenic centers at C6, C7, C10, C11, and C12 and a ring-closing metathesis to control the (Z)-double bond of the (E,Z)-dienic moiety. 相似文献