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61.
《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):843-847
Expression of MDR1 and MRP genes in patients with low‐grade and high‐grade non‐Hodgkin's lymphomas with primary bone marrow involvement before and after chemotherapy was investigated. The data demonstrate that overexpression of MDR1 and MRP genes in hematological malignancies elevates in patients after chemotherapy and correlates with poor clinic prognosis and more frequent recurrences of the malignancies. 相似文献
62.
Andreas Wagner Mirko Platzgummer Günther Kreismayr Heribert Quendler Gabriela Stiegler Boris Ferko 《Journal of liposome research》2013,23(3):311-319
A new scalable liposome production system is presented, which is based on the ethanol injection technique. The system permits liposome manufacture regardless of production scale, as scale is determined only by free disposable vessel volumes. Once the parameters are defined, an easy scale up can be performed by just changing the process vessels. These vessels are fully sterilizeable and all raw materials are transferred into the sanitized and sterilized system via 0.2 μm filters to guarantee an aseptic production.Liposome size can be controlled by the local lipid concentration at the injection point depending on process parameters like injection pressure, lipid concentration and injection rate. These defined process parameters are furthermore responsible for highly reproducible results with respect to vesicle diameters and encapsulation rates Compared to other technologies like the film method which is normally followed by size reduction through high pressure homogenization, ultrasonication or extrusion, no mechanical forces are needed to generate homogeneous and narrow distributed liposomes.Another important advantage of this method is the suitability for the entrapment of many different drug substances such as large hydrophilic proteins by passive encapsulation, small amphiphilic drugs by a one step remote loading technique or membrane association of antigens for vaccination approaches 相似文献
63.
64.
Patrycja Ledwoń Fosca Errante Anna Maria Papini Paolo Rovero Rafal Latajka 《化学与生物多样性》2021,18(2):e2000833
Cosmeceutical field, which merges cosmetics and pharmaceuticals, is nowadays a highly investigated research area, because a scientific demonstration of the claimed bioactivity of new cosmeceutical ingredients is increasingly requested. In fact, an aspect differentiating traditional cosmetics from cosmeceuticals is the identification and characterization of the active ingredients and demonstrating its efficacy in the claimed activity. An interesting group of bioactive cosmeceutical ingredients are peptides, which due to their particular properties, meets most of the requirements presented by the cosmeceutical industry when composing new formulas. In this context, beside bioactivity, two additional aspects have been recently considered, when dealing with peptides as cosmeceutical ingredients: bioavailability and stability. We describe herein novel methods applied in order to enhance peptides skin-penetration and stability, reviewing both scientific articles and patents, issued in the cosmeceutical arena. 相似文献
65.
《Journal of biological dynamics》2013,7(2):645-662
Vancomycin-resistant enterococci (VRE) infections have been linked to increased mortality and costs. A new model of a VRE-infested intensive care unit (ICU) is introduced. It incorporates critical features including the difference between colonization and infection, the role of special preventive care treatment cycles, fitness cost, and antibiotic use. Five patient stages are considered: susceptible, colonized with and without special preventive care, and infected with and without treatment. Parameter ranges are determined representing different ICUs and incorporated to numerically simulate the model. Basic reproductive number of the infection is derived and the impacts of the parameters are analysed. Strategies to minimize VRE infections and outbreak risk are explored with a focus on efficient and simultaneous control of critical parameters. In particular, threshold values of the level of special preventive care and ICU compliance rate are given to achieve desired goals under various constraints. 相似文献
66.
《Cell cycle (Georgetown, Tex.)》2013,12(8):1479-1480
Comment on: Vicente-Dueñas C, et al. Oncotarget 2012; Epub ahead of print; PMID:22408137. 相似文献
67.
《Expert review of proteomics》2013,10(6):653-655
The structure of prothrombin has eluded investigators for decades but recent efforts have succeeded in revealing the architecture of this important clotting factor. Unanticipated features have emerged outlining the significant flexibility of the zymogen due to linker regions connecting the γ carboxyglutamic domain, kringles and protease domain. A new, structure-based framework helps in defining a molecular mechanism of prothrombin activation, rationalizes the severe bleeding phenotypes of several naturally occurring mutations and identifies targets for drug design. 相似文献
68.
钠离子通道阻断剂河鲀毒素(TTX)是致命的毒素之一,却是极具价值的神经生物学和生理学等生命科学研究领域的工具药.近年来,越来越多的研究指出,TTX具有强大的局部麻醉潜能,有望成为替代氨基酯类和氨基酰胺类局部麻醉药、避免阿片类药物滥用的新型麻醉药物.本文综述TTX局部麻醉应用的辅助药物、TTX缓释及控释给药系统等相关研究,旨在为局部麻醉新药研发提供参考并探讨新的思路. 相似文献
69.
《Bioorganic & medicinal chemistry》2016,24(2):294-303
New cyclic RGD peptide-anticancer agent conjugates, with different chemical functionalities attached to the parent peptide were synthesized in order to evaluate their biological activities and to provide a comparative study of their drug release profiles. The Integrin binding c(RGDfK) penta-peptide was used for the synthesis of Camptothecin (CPT) carbamate and Chlorambucil (CLB) amide conjugates. Substitution of the amino acid Lys with Ser resulted in a modified c(RGDfS) with a new attachment site, which enabled the synthesis of an ester CLB conjugate. Functional versatility of the conjugates was reflected in the variability of their drug release profiles, while the conserved RGD sequence of a selective binding to the αv integrin family, likely preserved their recognition by the Integrin and consequently their favorable toxicity towards targeted cancer cells. This hypothesis was supported by a computational analysis suggesting that all conjugates occupy conformational spaces similar to that of the Integrin bound bio-active parent peptide. 相似文献
70.
Prasert Akkaramongkolporn Tanasait Ngawhirunpat Praneet Opanasopit 《AAPS PharmSciTech》2009,10(2):641-648
The differently sulfonated styrene–divinylbenzene cross-linked copolymer cationic exchange resins were prepared by oil-in-water
polymerization and varied degrees of sulfonation. Several characteristics of the obtained resins were evaluated, i.e., Fourier
transform infrared spectra, the ion-exchange capacity, microscopic morphology, size, and swelling. The resin characteristics
were altered in relation to the degree of sulfonation, proving that differently sulfonated resins could be prepared. The behavior
of chlorpheniramine (CPM) loading and in vitro release in the USP simulated gastric (SGF) and intestinal fluids (SIF) of the obtained resins were also evaluated. The CPM
loaded in the resinates (drug-loaded resins) increased with the increasing degree of sulfonic group and hence the drug binding
site in the employed resins. The CPM release was lower from the resins with the higher degree of sulfonic group due to the
increase in the diffusive path depth. The CPM release was obviously lower in SGF than SIF because CPM, a weak base drug, ionized
to a greater extent in SGF and then preferred binding with rather than releasing from the resins. In conclusion, the differently
sulfonated resins could be utilized as novel carriers for drug delivery. 相似文献