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71.
Genomewide profiling of copy‐number alteration in monoclonal gammopathy of undetermined significance 下载免费PDF全文
Aneta Mikulasova Jan Smetana Marketa Wayhelova Helena Janyskova Viera Sandecka Zuzana Kufova Martina Almasi Jiri Jarkovsky Evzen Gregora Petr Kessler Marek Wrobel Brian A. Walker Christopher P. Wardell Gareth J. Morgan Roman Hajek Petr Kuglik 《European journal of haematology》2016,97(6):568-575
Monoclonal gammopathy of undetermined significance (MGUS) is a benign condition with an approximate 1% annual risk of symptomatic plasma cell disorder development, mostly to multiple myeloma (MM). We performed genomewide screening of copy‐number alterations (CNAs) in 90 MGUS and 33 MM patients using high‐density DNA microarrays. We identified CNAs in a smaller proportion of MGUS (65.6%) than in MM (100.0%, P = 1.31 × 10?5) and showed median number of CNAs is lower in MGUS (3, range 0–22) than in MM (13, range 4–38, P = 1.82 × 10?10). In the MGUS cohort, the most frequent losses were located at 1p (5.6%), 6q (6.7%), 13q (30.0%), 14q (14.4%), 16q (8.9%), 21q (5.6%), and gains at 1q (23.3%), 2p (6.7%), 6p (13.3%), and Xq (7.8%). Hyperdiploidy was detected in 38.9% of MGUS cases, and the most frequent whole chromosome gains were 3 (25.6%), 5 (23.3%), 9 (37.8%), 15 (23.3%), and 19 (32.2%). We also identified CNAs such as 1p, 6q, 8p, 12p, 13q, 16q losses, 1q gain and hypodiploidy, which are potentially associated with an adverse prognosis in MGUS. In summary, we showed that MGUS is similar to MM in that it is a genetically heterogeneous disorder, but overall cytogenetic instability is lower than in MM, which confirms that genetic abnormalities play important role in monoclonal gammopathies. 相似文献
72.
Dorota Kida Aneta Zakrzewska Jacek Zborowski Magorzata Szulc Boena Karolewicz 《Materials》2021,14(14)
Polymers in drug formulation technology and the engineering of biomaterials for the treatment of oral diseases constitute a group of excipients that often possess additional properties in addition to their primary function, i.e., biological activity, sensitivity to stimuli, mucoadhesive properties, improved penetration of the active pharmaceutical ingredient (API) across biological barriers, and effects on wound healing or gingival and bone tissue regeneration. Through the use of multifunctional polymers, it has become possible to design carriers and materials tailored to the specific conditions and site of application, to deliver the active substance directly to the affected tissue, including intra-periodontal pocket delivery, and to release the active substance in a timed manner, allowing for the improvement of the form of application and further development of therapeutic strategies. The scope of this review is polymeric drug carriers and materials developed from selected multifunctional groups of natural, semi-synthetic, and synthetic polymers for topical therapeutic applications. Moreover, the characteristics of the topical application and the needs for the properties of carriers for topical administration of an active substance in the treatment of oral diseases are presented to more understand the difficulties associated with the design of optimal active substance carriers and materials for the treatment of lesions located in the oral cavity. 相似文献
73.
The key goal of this study was to characterize surface properties of chosen dental materials on the base on the contact angle measurements and surface free energy calculations. Tested materials were incubated in the simulated oral environment and drinks to estimate an influence of conditions similar to those in the oral cavity on wetting and energetic state of the surface. Types of materials were as follows: denture acrylic resins, composite and PET-G dental retainer to compare basic materials used in a prosthetics, restorative dentistry and orthodontics. The sessile drop method was used to measure the contact angle with the use of several liquids. Values of the surface free energies were estimated based on the Owens–Wendt, van Oss–Chaudhury–Good and Zisman’s methods. The research showed that surface wetting depends on the material composition and storage conditions. The most significance changes of CA were observed for acrylic resins (84.7° ± 3.8° to 65.5° ± 3.5°) and composites (58.8° ± 4.1° to 49.1° ± 5.7°) stored in orange juice, and for retainers (81.9° ± 1.8° to 99.6° ± 4.5°) incubated in the saline solution. An analysis of the critical surface energy showed that acrylic materials are in the zone of good adhesion (values above 40 mJ/m2), while BIS-GMA composites are in the zone of poor adhesion (values below 30 mJ/m2). Study of the surface energy of different dental materials may contribute to the development of the thermodynamic model of bacterial adhesion, based on the surface free energies, and accelerate the investigation of biomaterial interaction in the biological environment. 相似文献
74.
Karen Khachatryan Lusine Khachatryan Marcel Krzan Magdalena Krystyjan Lidia Krzemiska-Fiedorowicz Anna Lenart-Boro Aneta Koronowicz Mariola Drozdowska Gohar Khachatryan 《Materials》2021,14(12)
Natural polysaccharides, including hyaluronic acid, find a wide range of applications in biomedical sciences. There is a growing interest in nanocomposites containing hyaluronic acid and nanoparticles such as nanometals or graphene. In this study, we prepared foils of pure sodium hyaluronate and sodium hyaluronate containing nanosilver, graphene oxide, nanosilver/graphene oxide and characterized their properties. UV-vis spectroscopy and scanning electron microscopy (SEM) confirmed the formation of 10–20 nm silver nanoparticles. The structural changes were investigated using Fourier transforms infrared (FTIR) spectra and size exclusion chromatography. The obtained results suggest changes in molecular weights in the samples containing nanoparticles, which was highest in a sample containing nanosilver/graphene oxide. We also assessed the mechanical properties of the foils (thickness, tensile strength and elongation at break) and their wettability. The foils containing nanosilver and nanosilver/graphene oxide presented bacteriostatic activity against E. coli, Staphylococcus spp. and Bacillus spp., which was not observed in the control and sample containing graphene oxide. The composites containing graphene oxide and nanosilver/graphene oxide exhibited a cytotoxic effect on human melanoma WM266-4 cell lines (ATCC, Manassas, VA, USA). 相似文献
75.
Aneta Bartkowska 《Materials》2021,14(10)
The paper presents the results of a study of the microstructure, chemical composition, microhardness and corrosion resistance of Cr-B coatings produced on Vanadis 6 tool steel. In this study, chromium and boron were added to the steel surface using a laser alloying process. The main purpose of the study was to determine the impact of those chemical elements on surface properties. Chromium and boron as well as their mixtures were prepared in various proportions and then were applied on steel substrate in the form of precoat of 100 µm thickness. Depending on the type of precoat used and laser processing parameters, changes in microstructure and properties were observed. Coatings produced using precoat containing chromium and boron mixture were characterized by high microhardness (900 HV0.05–1300 HV0.005) while maintaining good corrosion resistance. It was also found that too low laser beam power contributed to the formation of cracks and porosity. 相似文献
76.
77.
Y-STR variation among Slavs: evidence for the Slavic homeland in the middle Dnieper basin 总被引:1,自引:0,他引:1
Rebała K Mikulich AI Tsybovsky IS Siváková D Dzupinková Z Szczerkowska-Dobosz A Szczerkowska Z 《Journal of human genetics》2007,52(5):406-414
A set of 18 Y-chromosomal microsatellite loci was analysed in 568 males from Poland, Slovakia and three regions of Belarus.
The results were compared to data available for 2,937 Y chromosome samples from 20 other Slavic populations. Lack of relationship
between linguistic, geographic and historical relations between Slavic populations and Y-short tandem repeat (STR) haplotype
distribution was observed. Two genetically distant groups of Slavic populations were revealed: one encompassing all Western-Slavic,
Eastern-Slavic, and two Southern-Slavic populations, and one encompassing all remaining Southern Slavs. An analysis of molecular
variance (AMOVA) based on Y-chromosomal STRs showed that the variation observed between the two population groups was 4.3%,
and was higher than the level of genetic variance among populations within the groups (1.2%). Homogeneity of northern Slavic
paternal lineages in Europe was shown to stretch from the Alps to the upper Volga and involve ethnicities speaking completely
different branches of Slavic languages. The central position of the population of Ukraine in the network of insignificant
AMOVA comparisons, and the lack of traces of significant contribution of ancient tribes inhabiting present-day Poland to the
gene pool of Eastern and Southern Slavs, support hypothesis placing the earliest known homeland of Slavs in the middle Dnieper
basin. 相似文献
78.
79.