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Journal of Neuro-Oncology - Patients diagnosed with primary central nervous system lymphoma (PCNSL) often face dismal outcomes due to the limited availability of therapeutic options. PCNSL cells...  相似文献   
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BackgroundThe evaluation of immune responses to RTS,S/AS01 has traditionally focused on immunoglobulin (Ig) G antibodies that are only moderately associated with protection. The role of other antibody isotypes that could also contribute to vaccine efficacy remains unclear. Here we investigated whether RTS,S/AS01E elicits antigen-specific serum IgA antibodies to the vaccine and other malaria antigens, and we explored their association with protection.MethodsNinety-five children (age 5–17 months old at first vaccination) from the RTS,S/AS01E phase 3 clinical trial who received 3 doses of RTS,S/AS01E or a comparator vaccine were selected for IgA quantification 1 month post primary immunization. Two sites with different malaria transmission intensities (MTI) and clinical malaria cases and controls, were included. Measurements of IgA against different constructs of the circumsporozoite protein (CSP) vaccine antigen and 16 vaccine-unrelated Plasmodium falciparum antigens were performed using a quantitative suspension array assay.ResultsRTS,S vaccination induced a 1.2 to 2-fold increase in levels of serum/plasma IgA antibodies to all CSP constructs, which was not observed upon immunization with a comparator vaccine. The IgA response against 13 out of 16 vaccine-unrelated P. falciparum antigens also increased after vaccination, and levels were higher in recipients of RTS,S than in comparators. IgA levels to malaria antigens before vaccination were more elevated in the high MTI than the low MTI site. No statistically significant association of IgA with protection was found in exploratory analyses.ConclusionsRTS,S/AS01E induces IgA responses in peripheral blood against CSP vaccine antigens and other P. falciparum vaccine-unrelated antigens, similar to what we previously showed for IgG responses. Collectively, data warrant further investigation of the potential contribution of vaccine-induced IgA responses to efficacy and any possible interplay, either synergistic or antagonistic, with protective IgG, as identifying mediators of protection by RTS,S/AS01E immunization is necessary for the design of improved second-generation vaccines.Clinical trial registration: ClinicalTrials.gov: NCT008666191.  相似文献   
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Parasitology Research - The article Green drugs in the fight against Anisakis simplex—larvicidal activity and acetylcholinesterase inhibition of Origanum compactum essential oil, written by...  相似文献   
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Heart disease is the leading cause of non-cancer death in childhood cancer survivors. to determine the prevalence of subclinical cardiac dysfunction using speckle tracking and compare its results with those obtained by classical methods of assessing left ventricular function and its relationship with different factors to identify the population at higher risk. Echocardiographic assessment of left ventricular function included ejection fraction, tissue Doppler, longitudinal/circumferential strains and biochemical parameters (troponin-T and Pro-BNP) in a cohort of 57 survivors of childhood acute leukaemia with at least 10 years since diagnosis. Ventricular dysfunction was found in 5.2% of patients in M-mode (ejection fraction—EF?<?53% with a reduction in the EF?≥?10%) and in 7% of patients with Simpson’s method, compared with 21.05 and 8.8% with suboptimal global longitudinal strain (GLS) and global circumferential strain, respectively. The GLS alteration was significantly correlated with lower values of left ventricular systolic function and was associated with high tumour risk (odds ratio [OR] 13.8), cumulative doses of anthracyclines?≥?250 mg/m2 (OR 7.6) and radiotherapy (OR 7.19). Biomarkers were not useful for the diagnosis of subclinical cardiomyopathy. Good reproducibility was obtained, with an intraobserver correlation of 93.6% and an interobserver correlation of 89.2% in the GLS. The alteration of the GLS was more prevalent than the alteration in the EF and was associated with the treatment received and high tumour risk. strain imaging seems to be a powerful tool to identify an increased number of survivor with an early myocardial injury.  相似文献   
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Structural characterization of biologically formed materials is essential for understanding biological phenomena and their enviro-nment, and for generating new bio-inspired engineering concepts. For example, nacre—the inner lining of some mollusk shells—encodes local environmental conditions throughout its formation and has exceptional strength due to its nanoscale brick-and-mortar structure. This layered structure, comprising alternating transparent aragonite (CaCO3) tablets and thinner organic polymer layers, also results in stunning interference colors. Existing methods of structural characterization of nacre rely on some form of cross-sectional analysis, such as scanning or transmission electron microscopy or polarization-dependent imaging contrast (PIC) mapping. However, these techniques are destructive and too time- and resource-intensive to analyze large sample areas. Here, we present an all-optical, rapid, and nondestructive imaging technique—hyperspectral interference tomography (HIT)—to spatially map the structural parameters of nacre and other disordered layered materials. We combined hyperspectral imaging with optical-interference modeling to infer the mean tablet thickness and its disorder in nacre across entire mollusk shells from red and rainbow abalone (Haliotis rufescens and Haliotis iris) at various stages of development. We observed that in red abalone, unexpectedly, nacre tablet thickness decreases with age of the mollusk, despite roughly similar appearance of nacre at all ages and positions in the shell. Our rapid, inexpensive, and nondestructive method can be readily applied to in-field studies.

Complex optical phenomena can emerge from a variety of biological or bio-inspired processes, from arrays of colors in peacocks (1) and other birds (2), butterflies (3), and opals (4), to the metal-like sheen of herring (5) and unique polarization-dependent properties of jewel beetles (6) and Pollia fruit (7). Nacre, or mother-of-pearl, is a prominent biologically formed mineral structure found throughout our oceans. It lines the inside of the shells formed by many mollusks, including bivalves, cephalopods, and gastropods. It features brilliant iridescent colors (Fig. 1) and is studied and emulated in part because of its outstanding mechanical performance (8, 9). The striking, colorful appearance of nacre has been a source of scientific curiosity since the days of Brewster (10), Rayleigh (11), and Raman (12, 13), and is the product of optical interference resulting from multiple interface reflections as light propagates through its stratified structure comprising stacks of transparent polygonal aragonite tablets (CaCO3) interspersed with organic polymer (chitin and proteins) layers (1416) (Fig. 1A). Nacre is one of seven mollusk shell structures (17). In the nacre structure, the aragonite tablets are typically 5 to 10 μm in diameter and hundreds of nanometers thick [200 to 1,100 nm across all shells, and 250 to 500 nm in red abalone (18)], while the organic sheets are an order of magnitude thinner (14, 16, 19). In columnar nacre formed by gastropods like abalone and snails (Fig. 1), co-oriented tablets are stacked on top of one another, while in sheet nacre formed by bivalves like pearl oysters and pen shells, co-oriented tablets are staggered diagonally (18) (see Movie S1 for an animation showing how co-oriented tablets are stacked in columnar nacre). Despite the significant structural and formation–mechanism differences, the thicknesses of tablets and organic layers are similar in columnar and sheet nacre, and so are the optical and mechanical behavior (20). The resulting palette of colors is primarily dependent on the nacre tablet thickness and the viewing angle, and the optical response that yields these colors can be understood as that of a Bragg reflector (21) with disorder in the layer thicknesses, where the optical band gaps are determined by the thicknesses of the transparent layers (5, 22, 23). Thus, the spectrum of light reflected from a nacre surface encodes information about its physical structure (Fig. 1 BD).Open in a separate windowFig. 1.(A) Nacre, the colorful iridescent inner lining of some mollusk shells. Here, the red abalone, or H. rufescens, shell features columnar nacre, which comprises thousands of layers of polygonal aragonite tablets interspersed with organic sheets. (B) A close-up photograph of the nacre surface shows a variety of colors and nonuniformities. (C and D) Given a broadband white light source illuminating nacre at a fixed angle of incidence, variations in color are observed due to the difference in average thickness of aragonite tablets comprising nacre. (E) Hyperspectral interference tomography (HIT) setup: A hyperspectral camera collects predominantly specular reflectance data across a sample illuminated by a collimated source at a fixed angle of incidence from the normal to the sample (θ). The reflected light is polarized using a wire-grid polarizer. (F) A color photograph of a region of nacre that was analyzed. (G) Map of the mean tablet thickness (MTT) obtained using HIT, overlaid on a grayscale rendering of the photograph in F. Highlighted in red is a 5 × 5-mm region used to analyze the ontogeny of nacre in Fig. 4. The region around this area was masked off using opaque tape, which is highlighted with the dashed white box.Understanding and characterizing the structure of nacre and other biomaterials have deep and surprising implications. For example, the average thickness of the tablets comprising ancient nacre can be used as a proxy for local ocean temperatures at the time of nacre formation, enabling paleoclimatology spanning hundreds of millions of years (18, 24, 25). The structure of nacre is also an inspiration for engineered materials thousands of times stronger than the constituent materials (15, 26, 27). To that end, new techniques have been developed to probe and understand the structure of nacre, such as polarization-dependent imaging contrast (PIC) mapping using X-ray absorption near-edge structure spectroscopy combined with photoemission electron spectromicroscopy (18, 28, 29), or X-ray nanotomography (30). However, these characterization techniques such as cross-sectional electron microscopy result in the destruction of the sample and are time-consuming and costly.Here, we present a method for rapid, nondestructive, and large-scale structural characterization of disordered and nonuniform stratified thin-film materials and apply it to the analysis of nacre. Our all-optical method employs hyperspectral imaging combined with thin-film modeling to extract nacre mean tablet thicknesses (MTTs) and tablet degree of disorder (σ)—defined as the standard deviation of the thicknesses—across large areas (Fig. 1 EG). This characterization method is designated as hyperspectral interference tomography (HIT). We used HIT to map the structure of mollusk shell nacre across many stages of development and identified a previously unexplored relationship between the age of the organism and the structure of the nacre layer. We investigated two particular species of nacre-forming mollusks, Haliotis rufescens (red abalone) and Haliotis iris (paua, or rainbow abalone; data only in SI Appendix), for which the aragonite tablet thicknesses lie within a range of 250 to 500 nm (18, 31); however, the method is applicable to any other transparent layered structure of animal, plant, geologic, or synthetic origin.  相似文献   
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