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991.
Association between clinical characteristics and types of the tau gene mutation has been observed in frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17). P301L mutation seldom causes parkinsonism as a leading symptom; instead it usually causes personality changes with aggressiveness and disinhibition. We experienced two patients of FTDP-17 from separate families (designated as patient 1 from family 1 and patient 2 from family 2). They had P301L mutation in common. However, their phenotypes were distinct from each other. Aggressive behaviors and disinhibition were the main symptoms in patient 1, whereas parkinsonism was the most prominent feature in patient 2. Their genotypes of the tau gene were different at three sites, i. e. in exon 6, in intron segment before exon 10, and in exon 13, though they do not bring amino acid change. Patient 1 had more prevalent C/C, C/C, and rare T/C respectively. Patient 2 had less prevalent T/T, A/A, and more prevalent T/T respectively. These findings suggest two things. Firstly, they do not share a common founder for P301L mutation. Secondly, either of the two less prevalent genotypes observed in patient 2 may be the factor to modify the phenotype of P301L mutation into those unusual clinical features with prominent parkinsonism. Accumulation of information as to phenotype-genotype association will settle this hypothesis. Received: 7 May 2001, Received in revised form: 23 October 2001, Accepted: 22 November 2001  相似文献   
992.
A simple collagen binding assay (CBA) for measuring activity of the von Willebrand factor cleaving protease in clinical samples is described, and results of fifty masked plasmapheresis samples rom patients with TTP/HUS and other diseases are presented. There was 97.5% concordance between the CBA and a multimer gel assay. The CBA identified low protease activity in 78% of patients who had a clinical syndrome consistent with TTP/HUS and in 2 of 10 sick controls, giving it a positive predictive value of 0.94. The heterogeneity regarding the presence or absence of vWF protease activity in patients with TTP/HUS was confirmed by finding a low negative predictive value of 0.50 with the CBA. The CBA detected inhibitors of the protease in 26 of 29 patients (90%) with TTP/HUS and low protease activity levels. The CBA is a useful clinical assay for examining von Willebrand factor protease activity and detecting inhibitors against the protease.  相似文献   
993.
A major issue that has long dogged federal human services demonstration programs is the perception that when federal dollars end, the programs end—regardless of any proven successes. Access to Community Care and Effective Services and Supports (ACCESS) was a 5-year federal demonstration project to foster partnerships between service providers for homeless people with serious mental illness and co-occurring substance abuse disorders; and to identify effective, replicable systems integration strategies. After federal funding ended, research teams visited the ACCESS sites to determine which project elements remained and which strategies were used by the sites to continue ACCESS. This article describes ACCESS services and systems integration activities retained by the sites, new funding streams, and strategies used to obtain continued funding.  相似文献   
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996.
Davidson R  O'Leary D 《Modern healthcare》2002,32(22):front cover, 6-front cov7, 14
The heads of the American Hospital Association and the Joint Commission on Accreditation of Healthcare Organizations waged a war of words this spring. At issue was the JCAHO's plan to seek a contract that the AHA contended would push the commission into the role of a regulator. Modern Healthcare broke the story about the disagreement. Now, Richard Davidson and Dennis O'Leary tell Modern Healthcare in an exclusive interview that they have patched up their differences.  相似文献   
997.
Airway irritation involves a variety of reflex mechanisms. Tracheal and bronchial C fibres and rapidly adapting fibres mediate cough, bronchoconstriction, and mucosal vasodilation. Workplace respiratory irritants can have a variety of effects in relation to asthma. Very high exposures can cause new-onset asthma, clinically presenting as reactive airways dysfunction syndrome or irritant-induced asthma. Symptoms after exposure to irritants depend on aggregate characteristics, water solubility and dose. Measurement of pulmonary function in response to irritants includes baseline spirometry, monitoring of across-shift changes and changes in non-specific bronchial responsiveness as well as bronchial responsiveness to inhaled allergens. Following irritant exposure, inflammatory changes within the airways are monitored by bronchoalveolar lavage or - less invasively - by sputum markers. A completely non-invasive approach not limited in repeatability is the investigation of inflammatory markers in exhaled air. However, the diagnostic and prognostic values of these novel markers have still to be demonstrated.  相似文献   
998.
999.
An index to benchmark pesticide mobility relevant to surface water runoff and soil erosion (surface water mobility index, or SWMI) was derived based on two key environmental fate parameters: degradation half-life and organic carbon-normalized soil/water sorption coefficient (Koc). Values assigned with the index of each individual compound correlate well with the concentration trend of 13 pesticides monitored in six Lake Erie, USA, tributaries from 1983 to 1991. Regression using a power function of SWMI fits concentration data well at various percentiles in the database for each tributary and all six tributaries combined, with r2 ranging from 0.71 to 0.94 for the concentrations at the 95th percentile. Good agreement was also obtained between SWMI and the time-weighted annual mean concentrations (r2 = 0.67-0.87). Although concentrations at or near peaks tend to be driven by rare hydrological events (intense precipitation immediately after application), SWMI explains the peak concentration data generally well (r2 = 0.53-0.86). The SWMI-concentration relationship was further evaluated with two other pesticide monitoring databases: the U.S. Geological Survey National Water Quality Assessment Program White River Study Unit (1991-1996) at Hazelton, Indiana, USA, and the Syngenta (previously Novartis) Voluntary Monitoring Program with Community Water Systems at the Higginsville City Lake, Missouri, USA (1995-1997). The ability of the proposed SWMI to discriminate pesticide runoff mobility and its correlation with surface water monitoring data can be significant in the development of screening methodologies and data-based models for government agencies and/or practitioners in general facing increasing pressure to assess pesticide occurrence in aquatic environments.  相似文献   
1000.
AIMS: This study asks if repeated Pavlovian pairings of a sipper tube (conditioned stimulus, CS) with food (unconditioned stimulus, US) will induce Pavlovian autoshaping conditioned responses (CRs), consisting of drinking of either 6% ethanol or water from the sipper CS. This study also tests predictions derived from the autoshaping model by asking if sipper CS-directed drinking will be retained, despite the absence of training for several weeks, and, in addition, if drinking rate is a negative function of sipper CS duration. METHODS: Autoshaping procedures, conducted in two daily sessions, consisted of the brief insertion of the sipper tube CS followed by the response-independent presentation of food US. For the Ethanol group (n = 8), the sipper CS contained 6% ethanol, whereas for the Water group (n = 8), the sipper CS contained tap water. Saccharin fading procedures were employed, whereas for both groups, during days 1-19, the sipper CS contained 0.1% saccharin, and thereafter across training days the concentration of saccharin was gradually reduced (0.07, 0.035, 0.0%). Following elimination of saccharin, both groups were maintained in their home cages during a 27-day retention interval, and then re-evaluated for autoshaping of drinking of unsweetened ethanol and water. Thereafter, across days, the duration of access to the sipper CS (5.0, 7.5, 10.0, 15.0 s) during each autoshaping trial was increased. RESULTS: Both groups increased drinking across the first 19 days of training with sipper CS-food US pairings, and, at 0.0% saccharin, the Ethanol group consumed 14.76 ml of 6% ethanol per day, resulting in a daily ethanol consumption of 2.77 g/kg. For both groups, daily levels of drinking before and after the 27-day retention interval were comparable, attesting to the durability of the acquired drinking effects. At each CS duration, the Ethanol group consumed more millilitres of fluid per day than did the Water group, and for the Ethanol group, peak drinking of 24.0 ml of 6% ethanol per day was observed at the 10 s CS duration. For both groups, drinking rate (millilitres of fluid consumed per second of CS duration), was a declining monotonic function of CS duration, resulting in a daily ethanol consumption of approximately 4.2 g/kg for the Ethanol group. CONCLUSIONS: These data reveal that these sipper CS-food US autoshaping procedures induce drinking in rats that is durable and negatively related to increasing CS duration. The effects of both variables are consistent with the hypothesis that drinking from the sipper CS is a Pavlovian autoshaping CR. Autoshaping of drinking in the Water group is observed despite the absence of water deprivation, and even more fluid is consumed by the Ethanol group than by the Water group. The high volumes of ethanol consumed during brief daily sessions suggest that Pavlovian autoshaping procedures may provide an animal learning model of binge drinking.  相似文献   
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