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The aim of the study was to describe the bronchial responsiveness to inhaled histamine and exercise in a randomly selected group of 527 children and adolescents from Copenhagen, aged between 7 to 16 years. The distribution of the bronchial responsiveness was described as (1) the provoking concentration that causes a 20% reduction in FEV1 (2) the dose-response slope (DRS), that is, the linear slope of the dose-response curve, and (3) reduction in FEV1 after 6 minutes of exercise on a treadmill. The distribution of the concentration that causes a 20% reduction in FEV1 in the responsive range was not significantly different from a unimodal distribution, although the findings were skewed toward the less responsive end of the range (p greater than 0.05). The subjects with asthma represented a subgroup within the responsive distribution tail rather than a separate distribution peak. In asymptomatic individuals, the values of DRS were distributed symmetrically on a logarithmic scale. The deviation from normal was such that the standard deviation only slightly underestimated the "normal" range. The distribution of the bronchial response to exercise was found to be significantly different from a normal distribution. However, a significant relationship was found between the bronchial response to inhaled histamine and exercise (p less than 0.0001). We conclude that there is a log-normal distribution of the bronchial response to inhaled histamine in a random sample of children and adolescents.  相似文献   
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Host cell proteases such as TMPRSS2 are critical determinants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) tropism and pathogenesis. Here, we show that antithrombin (AT), an endogenous serine protease inhibitor regulating coagulation, is a broad-spectrum inhibitor of coronavirus infection. Molecular docking and enzyme activity assays demonstrate that AT binds and inhibits TMPRSS2, a serine protease that primes the Spike proteins of coronaviruses for subsequent fusion. Consequently, AT blocks entry driven by the Spikes of SARS-CoV, MERS-CoV, hCoV-229E, SARS-CoV-2 and its variants of concern including Omicron, and suppresses lung cell infection with genuine SARS-CoV-2. Thus, AT is an endogenous inhibitor of SARS-CoV-2 that may be involved in COVID-19 pathogenesis. We further demonstrate that activation of AT by anticoagulants, such as heparin or fondaparinux, increases the anti-TMPRSS2 and anti-SARS-CoV-2 activity of AT, suggesting that repurposing of native and activated AT for COVID-19 treatment should be explored.  相似文献   
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Since specular microscopy of the cornea offers the opportunity to observe and measure cells in vivo without any outside interference this method forms an unrivalled basis for estimation of tissue shrinkage during various preparatory methods. Therefore a study was performed with the purpose of evaluating the degree of artifacts in each preparatory step from the living tissue in vivo to the final SEM specimen.The study was performed on rabbit corneas, the endothelium serving as measuring target. The in vivo state was recorded by specular microscopy. Unfixed corneas were studied by light microscopy unstained and stained by alizarin red S or silver nitrate. Fixation was performed intracamerally with 1.5% glutaraldehyde (Gla) by a pH, osmolarity, viscosity and intraocular pressure identical with the physiological values of rabbit eyes. Fixation was completed by immersion in 2.5% Gla for 1/2 h. Gla-fixed corneas were evaluated as above before osmification.Dehydration was performed either by graded acetone, by acetone in a gradient-free system, both followed by critical point drying (CPD).At all steps cells were counted using the same reference frame. The number of cells/mm2 was estimated and statistical analysis showed a shrinkage of 22 per cent (area) in unfixed tissue, 26 per cent (area) in normally dehydrated tissue and 37 per cent (area) in gradient free dehydrated tissue processed for SEM.This paper was presented in part at the Eighth Annual Meeting of the European Club for Ophthalmic Fine Structure in West Berlin on 28th, 29th March, 1980  相似文献   
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Objective: To compare the quality of semen in 1,055 Danish men born between 1950 and 1970 who are assumed to represent a random sample of the Danish male population of fertile age.Design: Retrospective review of data on semen quality at the time of the female partner's first IVF treatment.Setting: The Fertility Clinic, Odense University Hospital, Odense, Denmark.Patient(s): One thousand fifty-five male partners of women with tubal infertility who were referred for IVF treatment consecutively during the period 1990–1996.Intervention(s): Analysis of the semen samples delivered and used in connection with the couples' first IVF treatment.Main Outcome Measure(s): Year of birth, age at time of sample collection, sperm concentration, and semen volume.Result(s): The mean sperm concentration (±SD) was 183.7 x 106 mL and the mean semen volume (±SD) was 3.9 mL. A considerable variation in both parameters was found from year to year, but no significant change occurred in either parameter throughout the entire period. When four birth cohorts were compared, a later year of birth was not associated with any change in sperm concentration or semen volume.Conclusion(s): Sperm concentration and semen volume were not related to year of birth, indicating that sperm quality has not changed in the Danish male population during the last 20–30 years.  相似文献   
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Ultraviolet (UV) light has been associated with the development of human non-melanoma skin cancers (NMSC). Such cancers often exhibit mutations in the p53 tumour suppressor gene. In order to determine the UV-induced p53 mutation spectrum, a yeast expression vector that harbours a human wild-type p53 cDNA was UV-irradiated in vitro and transfected into a yeast strain that contained the ADE2 gene regulated by a p53-responsive promoter. Forty-five mutant clones contained 51 mutations. Seven mutations were tandem base pair substitutions, four of which being CC-->TT, hallmark mutations of UV mutagenesis. Eighty percent (41/51) of the mutations were single or non-tandem base pair substitutions, the majority of which (27/41) were C-->T transitions. Ninety-five percent of such mutations occurred at dipyrimidine sites. Through a rigorous statistical test, the UV-induced p53 mutation spectrum appears to differ significantly (P < 0.008) from the one induced by the antineoplastic drug chloroethyl-cyclohexyl-nitrosourea, and to be indistinguishable from the one observed in NMSC (P = 0.4). These results demonstrate that the assay allows the determination of carcinogen-specific p53 mutation fingerprints and represents a new tool for molecular epidemiology.   相似文献   
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Aim The Pro Children consortium consists of the following partners: Knut-Inge Klepp (Coordinator), Department of Nutrition, University of Oslo, Norway; Carmen Perez Rodrigo, Unidad de Nutricion Comunitaria, Bilbao, Spain; Inga Thorsdottir, Unit for Nutrition Research, Landspitali University Hospital, Reykjavik, Iceland; Pernille Due, Department of Social Medicine, University of Copenhagen, Denmark; Maria Daniel Vaz de Almeida, Faculdade de Ciências da Nutrição e Alimentação da Universidade do Porto, Portugal; Ibrahim Elmadfa and Alexandra Wolf, Institute of Nutrition, University of Vienna, Austria; Jóhanna Haraldsdóttir, Research Department of Human Nutrition, Royal Veterinary and Agricultural University, Copenhagen, Denmark; Johannes Brug, Erasmus Medical Center Rotterdam, Department of Public Health, The Netherlands; Michael Sjöström and Agneta Yngve, Unit for Preventive Nutrition, Karolinska Institutet, Stockholm, Sweden; Ilse De Bourdeaudhuij, Department of Movement and Sport Sciences, Ghent University, Belgium.The Pro Children study is designed to assess vegetable and fruit consumption and determinants of the consumption patterns among European school children and their parents. A second objective is to develop and test strategies for promoting increased consumption of vegetables and fruits among school children and their parents.Subjects and methods Surveys of national, representative samples of 11-year-old school children and their parents were conducted in nine countries during October–November 2003, i.e. in Austria, Belgium, Denmark, Iceland, The Netherlands, Norway, Portugal, Spain and Sweden. Comprehensive school-based educational programmes were developed and tested in three settings, i.e. in the Bilbao region, Spain, in Rotterdam, The Netherlands, and in Buskerud county of Norway. A 24-h recall format and frequency items assessing regular intake were used to assess vegetable and fruit consumption. Determinants were assessed employing the theoretical framework of the ASE model (Attitudes, Social Influences and Self-Efficacy), including cognitive factors, normative influences, skills and environmental barriers related to vegetable and fruit consumption. The intervention programmes were tested employing a group-randomized trial design where schools were randomly allocated to an intervention arm and a delayed intervention arm. Surveys among all participating children and their parents were conducted prior to the initiation of the intervention (September 2003; month 0), immediately after the end of the intervention (at month 8) and at the end of the subsequent school year (month 20).Results Preliminary data from the project indicate that girls eat vegetables and fruit significantly more often than do boys across all participating countries. There are no sex differences, however, with respect to perceived availability of vegetables and fruit at home and outside the home setting. In all countries, perceived availability appears to be significantly associated with reported frequency of both vegetable and fruit consumption.Conclusion Experience so far indicates that the Pro Children Project will succeed in producing valid and reliable research instruments for assessing vegetable and fruit consumption among school children and their parents and that comparable, comprehensive intervention programmes can be implemented across geographic and cultural settings within Europe.  相似文献   
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Extensive studies have been performed to evaluate different factors that may affect on spinal interbody fusion, but the role of intervertebral disc tissue in the fusion process remains unclear. To study the influence of intervertebral disc tissue on osteoblast metabolism, we harvested disc tissue from patients who had undergone spinal surgery. The nucleus pulposus and annulus fibrosus were separately co-cultured with osteoblast-like cells SaOS-2 by means of culture inserts or organ culture. We assayed alkaline phosphoatase activity, 3H-thymidine incorporation into the DNA, and production of collagen type I, IL-1beta, IL-6, IL-10, and TNF-alpha. Exposure of the nucleus pulposus (NP) to osteoblast-like cells revealed stimulation of alkaline phosphatase production, 3H-thymidine incorporation and collagen type I production. Exposure of the annulus fibrosus (AF) stimulated 3H-thymidine incorporation and collagen type I production, but did not affect ALP activity. IL-6 was detected after application of NP and AF. Interleukin IL-10, IL-1beta and TNF-alpha were all below detection levels after application of disc tissue. Our findings show that frozen disc tissue stimulates the metabolism of osteoblast-like cells in vitro.  相似文献   
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PURPOSE Positron emission tomography (PET) has been used in grading of CNS tumors in adults, whereas studies of children have been limited. PATIENTS AND METHODS Nineteen boys and 19 girls (median age, 8 years) with primary CNS tumors were studied prospectively by fluorine-18 2-fluoro-2-deoxy-D-glucose (FDG) PET with (n = 16) or without (n = 22) H(2)(15)O-PET before therapy. Image processing included coregistration to magnetic resonance imaging (MRI) in all patients. The FDG uptake in tumors was semiquantitatively calculated by a region-of-interest-based tumor hotspot/brain index. Eight tumors without histologic confirmation were classified as WHO grade 1 based on location, MRI, and clinical course (22 to 42 months). Results Four grade 4 tumors had a mean index of 4.27 +/- 0.5, four grade 3 tumors had a mean index of 2.47 +/- 1.07, 10 grade 2 tumors had a mean index of 1.34 +/- 0.73, and eight of 12 grade 1 tumors had a mean index of -0.31 +/- 0.59. Eight patients with no histologic confirmation had a mean index of 1.04. For these 34 tumors, FDG uptake was positively correlated with malignancy grading (n = 34; r = 0.72; P < .01), as for the 26 histologically classified tumors (n = 26; r = 0.89; P < .01). The choroid plexus papilloma (n = 1) and the pilocytic astrocytomas (n = 3) had a mean index of 3.26 (n = 38; r = 0.57; P < .01). H(2)(15)O-uptake showed no correlation with malignancy. Digitally performed PET/MRI coregistration increased information on tumor characterization in 90% of cases. CONCLUSION FDG PET of the brain with MRI coregistration can be used to obtain a more specific diagnosis with respect to malignancy grading. Improved PET/MRI imaging of the benign hypermetabolic tumors is needed to optimize clinical use.  相似文献   
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