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151.
Dr. Claudia Herrera León Noel Angelo Kalacas Dr. Alejandra Mier Dr. Peyman Sakhaii Dr. Franck Merlier Elise Prost Dr. Irene Maffucci Dr. Valentina Montagna Dr. Helena Mora-Radó Dr. Pradeep K. Dhal Dr. Bernadette Tse Sum Bui Prof. Dr. Karsten Haupt 《Angewandte Chemie (International ed. in English)》2023,62(34):e202306274
Tumor Necrosis Factor-α (TNF-α) is a cytokine that is normally produced by immune cells when fighting an infection. But, when too much TNF-α is produced as in autoimmune diseases, this leads to unwanted and persistent inflammation. Anti-TNF-α monoclonal antibodies have revolutionized the therapy of these disorders by blocking TNF-α and preventing its binding to TNF-α receptors, thus suppressing the inflammation. Herein, we propose an alternative in the form of molecularly imprinted polymer nanogels (MIP-NGs). MIP-NGs are synthetic antibodies obtained by nanomoulding the 3-dimensional shape and chemical functionalities of a desired target in a synthetic polymer. Using an in-house developed in silico rational approach, epitope peptides of TNF-α were generated and ‘synthetic peptide antibodies’ were prepared. The resultant MIP-NGs bind the template peptide and recombinant TNF-α with high affinity and selectivity, and can block the binding of TNF-α to its receptor. Consequently they were applied to neutralize pro-inflammatory TNF-α in the supernatant of human THP-1 macrophages, leading to a downregulation of the secretion of pro-inflammatory cytokines. Our results suggest that MIP-NGs, which are thermally and biochemically more stable and easier to manufacture than antibodies, and cost-effective, are very promising as next generation TNF-α inhibitors for the treatment of inflammatory diseases. 相似文献
152.
The aggregation state of several lithium enolates were calculated in the gas phase and in THF solution by the B3LYP DFT and MP2 methods. The gas phase free energies of aggregate formation were underestimated by the DFT calculations, compared to those obtained by the G3MP2 method, although DFT did correctly predict the hexamer to be the major gas phase species. The DFT calculations correctly predicted the tetramer to be the major species in THF, while MP2 underestimated the stability of the tetramer relative to the dimer. 相似文献
153.
Let Γ be a graph endowed with a reversible Markov kernel p, whose associated operator P is defined by \(Pf(x) = {\sum }_{y} p(x, y)f(y)\). We assume that the kernels pn(x, y) associated to Pn satisfy Gaussian upper bounds but do not assume they satisfy the Hölder continuity property and the temporal regularity. Denote by L = I ? P the discrete Laplacian on Γ. This article shows the weighted weak type (1, 1) estimates and the weighted Lp norm inequalities for the spectral multipliers of L. We also obtain the weighted Lp norm inequalities for the commutators of the spectral multipliers of L with BMO functions which are new even for the unweighted case. 相似文献
154.
Plastic Antibodies for Cosmetics: Molecularly Imprinted Polymers Scavenge Precursors of Malodors 下载免费PDF全文
Sofia Nestora Franck Merlier Dr. Selim Beyazit Elise Prost Dr. Luminita Duma Bérangère Baril Dr. Andrew Greaves Prof. Karsten Haupt Dr. Bernadette Tse Sum Bui 《Angewandte Chemie (International ed. in English)》2016,55(21):6252-6256
Molecularly imprinted polymers (MIPs) are synthetic antibody mimics capable of specific molecular recognition. Advantageously, they are more stable, easy to tailor for a given application and less expensive than antibodies. These plastic antibodies are raising increasing interest and one relatively unexplored domain in which they could outplay these advantages particularly well is cosmetics. Here, we present the use of a MIP as an active ingredient of a cosmetic product, for suppressing body odors. In a dermo‐cosmetic formulation, the MIP captures selectively the precursors of malodorous compounds, amidst a multitude of other molecules present in human sweat. These results pave the way to the fabrication of a novel generation of MIPs with improved selectivities in highly complex aqueous environments, and should be applicable to biotechnological and biomedical areas as well. 相似文献
155.
Iron-sulfur proteins are very versatile biological entities for which many new functions are continuously being unravelled. This review focus on their role in the initiation of radical chemistry, with special emphasis on radical-SAM enzymes, since several members of the family catalyse key steps in the biosynthetic pathways of cofactors such as biotin, lipoate, thiamine, heme and the molybdenum cofactor. It will also include other examples to show the chemical logic which is emerging from the presently available data on this family of enzymes. The common step in all the (quite different) reactions described here is the monoelectronic reductive cleavage of SAM by a reduced [4Fe-4S](1+) cluster, producing methionine and a highly oxidising deoxyadenosyl radical, which can initiate chemically difficult reactions. This set of enzymes, which represent a means to perform oxidation under reductive conditions, are often present in anaerobic organisms. Some other, non-SAM-dependent, radical reactions obeying the same chemical logic are also covered. 相似文献
156.
Thuy Bui Thi Phuong My Tran Thi Ai Hai Nguyen Thi Thanh Loan Huynh Thi Phuong Hieu Le Trung Hoa Tran Thai Bui Thanh Q. Tuong Ho Nhat Thuy Nguyen Thi Thu Dung Doan Kim Van Tat Pham Quy Phan Tu Nhung Nguyen Thi Ai 《Structural chemistry》2021,32(1):135-148
Structural Chemistry - Rice, well known as the most important staple food source worldwide, is highly susceptible to many infectious diseases, especially rice sheath blight caused by fungus... 相似文献
157.
Minh-Tri Le Viet-Nham Hoang Dac-Nhan Nguyen Thi-Hoang-Linh Bui Thien-Vy Phan Phuong Nguyen-Hoai Huynh Thanh-Dao Tran Khac-Minh Thai 《Molecules (Basel, Switzerland)》2021,26(11)
ABCG2 is an ABC membrane protein reverse transport pump, which removes toxic substances such as medicines out of cells. As a result, drug bioavailability is an unexpected change and negatively influences the ADMET (absorption, distribution, metabolism, excretion, and toxicity), leading to multi-drug resistance (MDR). Currently, in spite of promising studies, screening for ABCG2 inhibitors showed modest results. The aim of this study was to search for small molecules that could inhibit the ABCG2 pump. We first used the WISS MODEL automatic server to build up ABCG2 homology protein from 655 amino acids. Pharmacophore models, which were con-structed based on strong ABCG2 inhibitors (IC50 < 1 μM), consist of two hydrophobic (Hyd) groups, two hydrogen bonding acceptors (Acc2), and an aromatic or conjugated ring (Aro|PiR). Using molecular docking method, 714 substances from the DrugBank and 837 substances from the TCM with potential to inhibit the ABCG2 were obtained. These chemicals maybe favor synthesized or extracted and bioactivity testing. 相似文献
158.
Duong Van-Hao Nguyen Thanh Duong Bui Loat Van Kim Thanh Tien Duong Thang Duc Hoang Duc Huu Musthafa M. Saiyad Nguyen Quyet Huu Kovacs Tibor Tran Hoai-Nam 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(2):805-814
Journal of Radioanalytical and Nuclear Chemistry - Understanding concentration and mobility behavior of radionuclides in soil and plant plays an important role and application. In this study,... 相似文献
159.
The?Anh?Bui Xuan?Thinh?DuongEmail author 《Calculus of Variations and Partial Differential Equations》2017,56(6):177
The main aim of this paper is to prove the Calderón–Zygmund estimates for a general nonlinear parabolic equation of p(x, t)-Laplacian type in the weighted Lorentz spaces. Note that we only require some mild conditions on the nonlinearity of coefficients and the underlying domain. The result for these nonlinear parabolic equations is new even in the particular case when the growth p(x, t) is a constant. 相似文献
160.
Thi Hoai Nguyen Viet Duc Ho Thi Thao Do Huu Tai Bui Van Kiem Phan Katrin Sak 《Natural product research》2015,29(3):247-252
Chemical investigation of the aerial parts of Uvaria rufa (Dunal) Blume collected from Vietnam yielded one new lignan glycoside, ufaside (1), along with six known compounds, oxoanolobine (2), ergosta-4,6,8(14),22-tetraen-3-one (3), catechin (4), epicatechin (5), daucosterol (6) and glutin-5-en-3-one (7). Their chemical structures were determined by using NMR, HR-MS spectroscopic analyses and in comparison with the reported data. A cytotoxic analysis of U. rufa herb extracts was performed for the first time using nine human cancer cell lines (MCF-7, MDA-MB-231, LNCaP, MKN7, SW480, KB, LU-1, HepG2 and HL-60) derived from different tumour types. Of these seven constituents, compounds 2 and 3 displayed moderate cytotoxicity against the human lung adenocarcinoma cell line (LU-1) with IC50 values of 9.22 ± 1.02 μg/mL and 10.21 ± 1.16 μg/mL, respectively. 相似文献