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991.
Aubree Boulet-Craig MSc Philippe Robaey MD PhD Fanny Barlaam PhD Julie Laniel BSc Victor Oswald MSc Karim Jerbi PhD Serge Sultan PhD Laurence Affret-Bertout MSc Simon Drouin PhD Maja Krajinovic PhD Caroline Laverdière MD PhD Daniel Sinnett PhD Pierre Jolicoeur PhD Sarah Lippé PhD 《Cancer》2019,125(20):3639-3648
992.
Scott V. Adams Brian Barrick Emily P. Christopher Martin M. Shafer Xiaoling Song Hugo Vilchis 《Archives of environmental & occupational health》2016,71(6):338-346
Exposure to As, Cd, Pb, and U among older Hispanic adults residing in underserved communities in southern New Mexico was investigated. Personal information was obtained by standardized interview from 188 adults aged 40–85 years. Urinary metal concentrations were measured and compared to results from the National Health and Nutritional Examination Survey (NHANES). Urinary As and U in study participants significantly (p < .05) exceeded NHANES reference values. Elevated urinary As concentration was significantly associated with older age, Latin American birthplace, clinic site, private-well drinking water, higher self-rated health, and diabetes. Higher urinary Cd was significantly associated with older age, clinic site, female sex, agricultural work, and current cigarette smoking. No personal characteristics were significantly associated with urinary Pb or U. Our results suggest elevated levels of As and U in this population. 相似文献
993.
Mokhlesur M. Rahman Mohd Adil Alias M. Yusof Yunus B. Kamaruzzaman Rezaul H. Ansary 《Materials》2014,7(5):3634-3650
In this work, batch adsorption experiments were carried out to investigate the suitability of prepared acid activated carbons in removing heavy metal ions such as nickel(II), lead(II) and chromium(VI). Acid activated carbons were obtained from oil palm and coconut shells using phosphoric acid under similar activation process while the differences lie either in impregnation condition or in both pretreatment and impregnation conditions. Prepared activated carbons were modified by dispersing hydrated iron oxide. The adsorption equilibrium data for nickel(II) and lead(II) were obtained from adsorption by the prepared and commercial activated carbons. Langmuir and Freundlich models fit the data well. Prepared activated carbons showed higher adsorption capacity for nickel(II) and lead(II). The removal of chromium(VI) was studied by the prepared acid activated, modified and commercial activated carbons at different pH. The isotherms studies reveal that the prepared activated carbon performs better in low concentration region while the commercial ones in the high concentration region. Thus, a complete adsorption is expected in low concentration by the prepared activated carbon. The kinetics data for Ni(II), Pb(II) and Cr(VI) by the best selected activated carbon fitted very well to the pseudo-second-order kinetic model. 相似文献
994.
995.
Immune protection of the gut in early life depends on provision of maternal antibodies, particularly that of IgA. In precocial birds (in this study Gallus gallus domesticus) the egg provides the only source of maternal antibodies, IgA inclusive. The gut-life of IgA in hatchlings is expected to be brief due to antigen binding and intestinal washout, and maternal IgA is likely to be depleted prior to immune independence at 7–10 days of age in the domestic fowl. We followed the track of maternal IgA in mucosal surfaces of the fowl and describe for the first time a mechanism that might provide the means to extend the active period of maternal IgA in the gut. Maternal IgA was located in the gut, lung, and cloacal bursa in embryos and hatchlings prior to the appearance of endogenic IgA positive plasma cells (D3 in the bursa or D7 in the gut and lung); the source of IgA was most probably the yolk, as the plasma was devoid of IgA till D7 post-hatch. The levels of maternal IgA decreased with time, but were still easily determined at the onset of endogenous IgA production following maturation of the adaptive immune system. Persistence of maternal IgA in the gut was enabled by goblet cell up-take by a yet un-described mechanism, and its consequent release in a mucin-like layer on enterocyte apical surfaces. 相似文献
996.
This study examines the significance (between-groups comparisons) and frequency (within-group analyses) of deficits in developmental dyslexia (DD, mainly deficits in decoding and phonemic awareness), specific language impairment (SLI, mainly deficits in listening comprehension), or both (mainly deficits in phonological short-term memory [STM]). Participants included two groups of children who had received a diagnosis of either SLI (N = 15) or DD (N = 15). For the between-groups comparison, the groups were matched pairwise on nonverbal IQ to 30 chronological age controls (CAC) and 30 reading level controls (RLC). For the within-group analyses, the participants were compared to 91 CACs and 63 RLCs. We developed tasks not used for the diagnoses to assess phonological skills (decoding, phonemic awareness, phonological STM) and non-phonological skills (listening and reading comprehension). SLI children scored lower than both DD children and RLCs on tasks assessing listening and reading comprehension, and lower than RLCs on phonological STM and phonemic awareness. Within-group comparisons showed that a higher proportion of SLI than DD children presented severe deficits in the same four domains. The opposite pattern was found for decoding skills (7 SLI children with a severe deficit, versus 13 in the DD group). These findings are discussed in the light of models explaining the overlap between SLI and DD. They highlight the need to assess both phonological and non-phonological skills in SLI and DD children, using both between- and within-groups designs. 相似文献
997.
《International journal of radiation biology》2013,89(3):194-204
Purpose:?The DNA double-strand break (DSB) damage response induced by high energy charged particles on lung fibroblast cells embedded in a 3-dimensional (3-D) collagen tissue equivalents was investigated using antibodies to the DNA damage response proteins gamma-histone 2AX (γ-H2AX) and phosphorylated DNA-PKcs (p-DNA-PKcs).Materials and methods:?3-D tissue equivalents were irradiated in positions across the linear distribution of the Bragg curve profiles of 307.7 MeV/nucleon, 556.9 MeV/nucleon, or 967.0 MeV/nucleon 56Fe ions at a dose of 0.30 Gy.Results:?Patterns of discrete DNA damage streaks across nuclei or saturated nuclear damage were observed, with saturated nuclear damage being more predominant as samples were positioned closer to the physical Bragg peak. Quantification of the DNA damage signal intensities at each distance for each of the examined energies revealed a biological Bragg curve profile with a pattern of DNA damage intensity similar to the physical Bragg curve for the particular energy. Deconvolution microscopy of nuclei with streaked or saturated nuclear damage pattern revealed more details of the damage, with evidence of double-strand breaks radially distributed from the main particle track as well as multiple discrete tracks within saturated damage nuclei.Conclusions:?These 3-D culture systems can be used as a biological substrate to better understand the interaction of heavy charged particles of different energies with tissue and could serve as a basis to model space-radiation-induced cancer initiation and progression. 相似文献
998.
目的 制备两种EDTA键合硅胶(SG-EDTA)并对其Cu2+吸附性能进行研究.方法 采用均相法和异相法制备SG-EDTA.结果 均相法制备SG-EDTA的收率比异相法制备SG-EDTA高;SG-EDTA在pH2时对Cu2+表现出了最大吸附量;从动力学吸附曲线来看,异相法与均相法制备的SG-EDTA对铜离子的吸附行为无明显差异.SG-EDTA在吸附动力学机制方面属于液膜扩散且符合拟二级动力学吸附;热力学吸附过程可用Freundlich热力学模型描述.结论 两种方法制备的SG-EDTA吸附量分别为1.413、1.457 mmol·g-1.吸附重金属离子后,均相法制备的EDTA键合硅胶较异相法制备的更易洗脱. 相似文献
999.
S. U. Kamath B. Pemiah K. S. Rajan S. Krishnaswamy S. Sethuraman U. M. Krishnan 《Indian journal of pharmaceutical sciences》2014,76(6):495-503
Rasasindura is a mercury-based nanopowder synthesized using natural products through mechanothermal processing. It has been used in the Ayurvedic system of medicine since time immemorial for various therapeutic purposes such as rejuvenation, treatment of syphilis and in genital disorders. Rasasindura is said to be composed of mercury, sulphur and organic moieties derived from the decoction of plant extracts used during its synthesis. There is little scientific understanding of the preparation process so far. Though metallic mercury is incorporated deliberately for therapeutic purposes, it certainly raises toxicity concerns. The lack of gold standards in manufacturing of such drugs leads to a variation in the chemical composition of the final product. The objective of the present study was to assess the physicochemical properties of Rasasindura samples of different batches purchased from different manufacturers and assess the extent of deviation and gauge its impact on human health. Modern characterization techniques were employed to analyze particle size and morphology, surface area, zeta potential, elemental composition, crystallinity, thermal stability and degradation. Average particle size of the samples observed through scanning electron microscope ranged from 5-100 nm. Mercury content was found to be between 84 and 89% from elemental analysis. Despite batch-to-batch and manufacturer-to-manufacturer variations in the physicochemical properties, all the samples contained mercury in the form of HgS. These differences in the physicochemical properties may ultimately impact its biological outcome. 相似文献
1000.
《Revue neurologique》2022,178(3):196-205
Primary Lateral Sclerosis (PLS) is an uncommon motor neuron disorder. Despite the well-recognisable constellation of clinical manifestations, the initial diagnosis can be challenging and therapeutic options are currently limited. There have been no recent clinical trials of disease-modifying therapies dedicated to this patient cohort and awareness of recent research developments is limited. The recent consensus diagnostic criteria introduced the category ‘probable’ PLS which is likely to curtail the diagnostic journey of patients. Extra-motor clinical manifestations are increasingly recognised, challenging the view of PLS as a 'pure' upper motor neuron condition. The post mortem literature of PLS has been expanded by seminal TDP-43 reports and recent PLS studies increasingly avail of meticulous genetic profiling. Research in PLS has gained unprecedented momentum in recent years generating novel academic insights, which may have important clinical ramifications. 相似文献