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71.
Summary These guide-lines provide a framework for the local arrangement of near patient testing (NPT) services for haematology tests. The guidance may be applied to medical and surgical units within hospitals (e.g. ITU, renal dialysis units, casualty) as well as general practitioners' surgeries, for blood counts and coagulation testing. The professional head of the central laboratory must take responsibility for all aspects of the NPT service, although there should be full discussion with the clinical departments involved and joint ownership of the results. NPT operators must be trained and accredited by the central laboratory. Equipment selected should normally have received a satisfactory evaluation report from the Medical Devices Agency (MDA), and should generate results that are comparable with those of the central laboratory. If a full MDA operation evaluation has not been performed, the purchaser should perform a local assessment according to the protocol in this document. The suitability of the equipment, imprecision, and comparability must be studied. The NPT equipment must be properly maintained and calibrated, and a record of patient identity, date and time of testing, reagent lot numbers, and operator must be kept. The central laboratory must participate in a suitable external quality assessment programme (EQA), and provide systems for EQA and internal quality control (IQC) of the NPT site.  相似文献   
72.
Chan  WC; Link  S; Mawle  A; Check  I; Brynes  RK; Winton  EF 《Blood》1986,68(5):1142-1153
Two major types of lymphocytosis of large granular lymphocytes (LGLs) were observed. The proliferating LGLs in each type had distinct immunophenotypes, functional characteristics, and probably belonged to different cell lineages. The more common form (Type A) consisted of cells derived from the T cell lineage and had the T suppressor/cytotoxic phenotype (T11+, T3+, T8+). The expression of the Leu 7 and HLA-DR antigen was variable. These cells did not have natural killer (NK) function but showed a variable degree of antibody-dependent cell-mediated cytotoxic (ADCC) activity. Neutropenia was invariably present and rheumatoid arthritis and autoantibodies were frequent associations. These lymphocytes had many similarities to the major type of LGLs present in normal adult bone marrow. The other type of LGL lymphocytosis (Type B) consisted of cells lacking the antigens T3 and T8 but expressing M1 and NKH1. These cells possessed strong NK and ADCC activity but their cell lineage was not clear. Neutropenia and autoimmune phenomena were not detected. The cytochemical characteristics of the LGL granules from both types of patients were similar but differences in ultrastructure were observed. LGLs from Type B patients proliferated in the presence of Interleukin 2 (IL-2) and 12- O-tetradecanoyl-phorbol-13 acetate (TPA). Significant changes in their basic T11+, T3-, T8- phenotype were not observed. IL-2 and TPA, however, had profound influence on the NK function of the cells with enhancement in the case of IL-2 and marked suppression when stimulated by TPA.  相似文献   
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74.
Numerical simulations reveal a family of hierarchical and chiral multicontinuous network structures self-assembled from a melt blend of Y-shaped ABC and ABD three-miktoarm star terpolymers, constrained to have equal-sized A/B and C/D chains, respectively. The C and D majority domains within these patterns form a pair of chiral enantiomeric gyroid labyrinths (srs nets) over a broad range of compositions. The minority A and B components together define a hyperbolic film whose midsurface follows the gyroid minimal surface. A second level of assembly is found within the film, with the minority components also forming labyrinthine domains whose geometry and topology changes systematically as a function of composition. These smaller labyrinths are well described by a family of patterns that tile the hyperbolic plane by regular degree-three trees mapped onto the gyroid. The labyrinths within the gyroid film are densely packed and contain either graphitic hcb nets (chicken wire) or srs nets, forming convoluted intergrowths of multiple nets. Furthermore, each net is ideally a single chiral enantiomer, induced by the gyroid architecture. However, the numerical simulations result in defect-ridden achiral patterns, containing domains of either hand, due to the achiral terpolymeric starting molecules. These mesostructures are among the most topologically complex morphologies identified to date and represent an example of hierarchical ordering within a hyperbolic pattern, a unique mode of soft-matter self-assembly.Liquid crystals formed by molecular self-assembly provide fascinating examples of complicated space partitions in soft-material science. Relatively complex examples are the bicontinuous mesostructures found ubiquitously in both natural and synthetic soft matter, including lipid–water systems and block copolymer melts, namely the double diamond (symmetry ), the primitive , and, particularly, the gyroid mesophases. The structure of these mesophases can be described by a molecular membrane folded onto one of the three simplest triply periodic minimal surfaces (TPMS), namely the D, P, and G(yroid) surfaces, named by Schoen in the 1960s (1). From a 3D perspective, these structures are characterized by the nets describing the pair of mutually threaded labyrinths carved out of space by the convoluted hyperbolic architecture of the TPMS. For the gyroid, this is a racemic mixture of two chiral srs nets, one left- and the other right-handed [the three-letter nomenclature follows the Reticular Chemistry Structure Resource naming convention for 3D nets (2)]. This leads to an overall achiral structure when the two nets are chemically identical, which is the case in most experimentally identified gyroid liquid-crystal structures. One such structure recently reported is a gyroid assembly found in an ABC three-miktoarm star terpolymer melt (3). In this structure, the majority C component constitutes the two labyrinth nets while the A and B minority components together form the dividing membrane. Because of the connectivity of the star molecular architecture and because all components microphase separate, the A and B components segregate on the dividing hyperbolic interface. This structure is an experimental indication of a unique mode of self-assembly, namely “hierarchical assembly of a hyperbolic pattern.” Complementing this finding and further motivating our work reported here, a recent simulation study by one of us (J.J.K.K.) explored self-assembly of blends of equal amounts of two distinct three-miktoarm stars, namely ABC and ABD three-miktoarm star terpolymers (Fig. 1). Both molecules were assigned equal molecular weights, and the proportions of the equal volume C (green) and D (yellow) chains relative to the equal A (red) and B (blue) chains were varied (4). Despite these severe compositional constraints, a number of unique four-colored mesophases were revealed. The most striking feature of the predicted phase behavior in this system was the presence of interesting patterns whose general features are reminiscent of the gyroid, albeit far more complex in both geometric and topological aspects. In the system reported here, two ordering regimes form. At the larger length scale, ordering induces a gyroid-like membrane, which is itself also spontaneously ordered at a smaller length scale, giving unique microdomain patterning due to the membrane confinement to a hyperbolic curved interface. Each of these patterns contain distinct numbers and types of interwoven 2D and 3D A and B domains forming nets of equal hand, immersed within the hyperbolic interface between an enantiomeric pair of C and D srs nets. These structures are spectacularly convoluted in 3D space and correspond to special members of a sequence of chiral cubic patterns that emerge by local striping of the gyroid membrane. We demonstrate how this is performed systematically by mapping a particular family of tilings in the hyperbolic plane onto the gyroid in 3D euclidean space. Careful analysis of the morphologies formed in the simulations, described below, reveals the presence of up to three distinct chiral cubic mesophases within this striped gyroid region of the phase diagram. We explore the geometric and topological variety of these self-assemblies in detail and discuss how they emerge as a response to a hierarchy of frustrations imposed by the three-arm star molecular architecture, acting in both two and three dimensions.Open in a separate windowFig. 1.(A) Model ABC and ABD three-miktoarm star terpolymer molecules. All molecules contain equal-sized A (red) and B (blue) arms, and longer C (green) and D (yellow) arms, also of equal size. The parameter x (equal to in this image), corresponds to the number ratio of C to A beads. (B) C and D domain geometry, a pair of intertwined srs nets. (C–G) Single-unit cell snapshots illustrating the curved striped pattern formed by the minority components A and B for varying x. (C) x = 2, (D) x = 3.33, (E) x = 3.67, (F) x = 5, and (G) x = 6. Note the threefold branching of the stripes for all values of x.  相似文献   
75.
Typhoid fever affects an estimated 22 million people annually and causes 216,000 deaths worldwide. We conducted an investigation in August and September 2010 to examine the acceptability of typhoid vaccine in Neno District, Malawi where a typhoid outbreak was ongoing. We used qualitative methods, including freelisting exercises, key informant and in-depth interviews, and group discussions. Respondents associated illness with exposure to “bad wind,” and transmission was believed to be airborne. Typhoid was considered extremely dangerous because of its rapid spread, the debilitating conditions it produced, the number of related fatalities, and the perception that it was highly contagious. Respondents were skeptical about the effectiveness of water, sanitation, and hygiene (WaSH) interventions. The perceived severity of typhoid and fear of exposure, uncertainty about the effectiveness of WaSH measures, and widespread belief in the efficacy of vaccines in preventing disease resulted in an overwhelming interest in receiving typhoid vaccine during an outbreak.  相似文献   
76.

Aims/hypothesis  

Diagnosing MODY is difficult. To date, selection for molecular genetic testing for MODY has used discrete cut-offs of limited clinical characteristics with varying sensitivity and specificity. We aimed to use multiple, weighted, clinical criteria to determine an individual’s probability of having MODY, as a crucial tool for rational genetic testing.  相似文献   
77.
78.
ABSTRACT: BACKGROUND: According to the UK Adult Dental Health Survey (2009) 15% of adults aged 65-74, 30% aged 75-84 and 47% aged >85 years are edentulous and require complete dentures. Patients' quality of life and nutrition status are affected by poor dentures. The quality of the dental impression is the most important issue for improving the fit and comfort of new dentures. There is paucity of RCT evidence for which impression material is best for complete dentures construction. This study aims to compare two impression materials for effectiveness and cost effectiveness. METHODS: IMPROVDENT is a double-blind crossover trial comparing the use of alginate and silicone, two commonly used denture impression materials, in terms of patient preference and cost-effectiveness. Eighty five edentulous patients will be recruited and provided with two sets of dentures, similar in all aspects except for the impression material used (alginate or silicone). Patients will try both sets of dentures for a two-week period, unadjusted, to become accustomed to the feel of the new dentures (habituation period). Patients will then wear each set of dentures for a period of 8 weeks (in random order) during which time the dentures will be adjusted for optimum comfort. Finally, patients will be given both sets of dentures for a further two weeks to wear whichever denture they prefer (confirmation period). Patients will be asked about quality of life and to rate dentures on function and comfort at the end of each trial period and asked which set they prefer at the end of the habituation period (unadjusted denture preference) and confirmation period (adjusted denture preference). A health economic evaluation will estimate incremental cost-effectiveness ratios of producing dentures from the two materials. A qualitative study will investigate the impact of dentures on behaviour and quality of life. Funding: IMPROVDENT is funded by NIHR RfPB (PB-PG-0408-16300). DISCUSSION: This trial aims to provide evidence on the costs and quality of dentures cast from two different commonly used impression materials; the intention is to significantly impact on the quality of denture production within NHS dentistry. Trial Registration ISRCTN Register: ISRCTN01528038 UKCRN Portfolio ID: 8305.  相似文献   
79.
This case report illustrates the case of a patient who developed recurrent strokes after a pace maker lead was inserted into his left ventricle. It was removed successfully by the cardiothoracic surgeons but he remained very dependent functionally. This case highlights the importance of always reviewing the electrocardiogram and chest radiograph after the insertion of a pacemaker as late diagnosis of this complication can leave the patient with significant morbidity.  相似文献   
80.
Schistosomiasis control programs aim to reduce morbidity but are evaluated by infection prevalence and intensity reduction. We present baseline cross-sectional data from a nested cohort study comparing indicators of morbidity for measuring program impact. Eight hundred twenty-two schoolchildren 7–8 years of age from Nyanza Province, Kenya, contributed stool for diagnosis of Schistosoma mansoni and soil-transmitted helminths (STH) and blood smears for malaria, and were evaluated for anemia, quality of life, exercise tolerance, anthropometry, and ultrasound abnormalities. Schistosoma mansoni, STH, and malaria infection prevalence were 69%, 25%, and 8%, respectively. Only anemia and S. mansoni infection (adjusted odds ratio [aOR] = 1.70; confidence interval [CI] = 1.03–2.80), and hepatomegaly and heavy S. mansoni infection (aOR = 2.21; CI = 1.19–4.11) were associated. Though anemia and hepatomegaly appeared most useful at baseline, additional morbidity indicators may be sensitive longitudinal measures to evaluate schistosomiasis program health impact.  相似文献   
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