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We examine and refine the Fagerström Tolerance Questionnaire (FTQ; Fagerström, 1978). The relation between each FTQ item and biochemical measures of heaviness of smoking was examined in 254 smokers. We found that the nicotine rating item and the inhalation item were unrelated to any of our biochemical measures and these two items were primary contributors to psychometric deficiencies in the FTQ. We also found that a revised scoring of time to the first cigarette of the day (TTF) and number of cigarettes smoked per day (CPD) improved the scale. We present a revision of the FTQ: the Fagerström Test for Nicotine Dependence (FTND).  相似文献   
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Current antitachycardia systems such as the automatic implantable cardioverter/defibrillator (AICD), detect tachyarrhythmias primarily by sensing rate and thereby perform inadequately in differentiating hemodynamically stable from unstable arrhythmias. As a result, these devices may discharge during stable tachycardias (such as sinus tachycardia), causing discomfort to the patient and depleting the device's limited energy supply. If a parameter which could reflect the particular hemodynamic state of a tachycardia were incorporated into the sensing algorithm of these systems, function may be more hemodynamically precise and discharge specificity may be improved.  相似文献   
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BackgroundThe incidence of peripartum cardiomyopathy (PPCM) is known through referral center databases that may be affected by referral, misclassification, and other biases. We sought to determine the community-based incidence and natural history of PPCM using the Rochester Epidemiology Project.Methods and ResultsIncident cases of PPCM occurring between January 1, 1970, and December 31, 2014, were identified in Olmsted County, Minnesota. A total of 15 PPCM cases were confirmed yielding an incidence of 20.3 cases per 100,000 live births in Olmsted County, Minnesota. Clinical information, disease characteristics, and outcomes were extracted from medical records in a 27-county region of the Rochester Epidemiology Project including Olmsted County and matched in a 1:2 ratio with pregnant women without PPCM. A total of 48 women were identified with PPCM in the expanded 27-county region. There was 1 death and no transplants over a median of 7.3 years of follow-up. Six of the 23 women with subsequent pregnancies developed recurrent PPCM, all of whom recovered. Migraine and anxiety were identified as novel possible risk factors for PPCM.ConclusionsThe population-based incidence of PPCM was 20.3 cases per 100,000 live births in Olmsted County, Minnesota. Cardiovascular outcomes were generally excellent in this community cohort.  相似文献   
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The United States Environmental Protection Agency's Integrated Risk Information System (IRIS) includes hazard identification and dose-response assessment values developed by Agency scientists. Uncertainty factors (UFs) are used in the development of IRIS values to address the lack of information in five main areas. The standard UFs account for interspecies uncertainty (UFA) and intraspecies variability (UFH). The UFA addresses uncertainty related to the extrapolation of data from animals to humans, whereas the UFH addresses variability amongst individuals (i.e., intrahuman). Additional UFs have been employed to account for database incompleteness, extrapolations from a lowest-observed-adverse-effect level in the absence of a no-observed-adverse-effect level (UFL), and subchronic-to-chronic extrapolation (UFS). A sixth UF designated as “other uncertainty factors” (UFO) has also been applied in place of the UFL to account for uncertainty with the adversity of points of departure obtained using benchmark dose modeling. This review will discuss how UFL, UFS, and UFO have been applied in IRIS assessments, along with the rationale used to describe the choice of UF values that deviate from the standard default of 10.  相似文献   
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The hemodynamic responses to rapid atrial and ventricular pacing were examined in 10 closed-chest anesthetized dogs in an attempt to distinguish hemodynamically stable from unstable tachycardias. Pressure monitoring catheters were placed in the femoral artery, right atrium, and right ventricle to measure mean arterial pressure, mean right atrial pressure, and mean right ventricular pressure at baseline heart rate and after rapid high right atrial and right ventricular apex pacing. Pressures recorded during rapid pacing (average of the pressures at 30 and 60 seconds of pacing) at pacing rates of 180, 250, and 280/minute were compared to those recorded initially at baseline heart rates. Rapid right ventricular apex pacing resulted in significant increases in mean right atrial pressure (from 6 ± 1 mmHg (mean ± standard error) to 12 ± 1 mmHg, a 100% increase, P < 0.001) and mean right ventricular pressure (from 11 ±1 mmHg to 16 ± 1 mmHg, a 45% increase, p < 0.02) with marked hemodynamic compromise (mean arterial pressure decreased from 85 ± 6 mmHg to 50 ± 6 mmHg, a 41% decrease, P < 0.01). These parameters remained stable (no statistically significant difference from baseline) during high right atrial pacing. In half of the dogs high right atrial pacing at rates 250 resulted in atrioventricular Wenckebach. Thus, it is concluded that mean right atrial pressure and mean right ventricular pressure may be useful in distinguishing hemodynamically significant tachycardias, and in the future design of antitachycardia devices.  相似文献   
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Objective: To monitor key processes and outcomes in joint health and social services community psychogeriatric teams. Design: Six month follow-up of new referrals to 4 teams in Cambridge. Data collected from structured clinical assessment forms at baseline and interviews with keyworkers at follow-up. Data for groups with and without dementia were compared. Setting: Two rural and two urban teams in area with relatively large long stay inpatient facility but low independent sector provision. All were routine service teams, rather than run for research purposes. Main outcome measures: The main outcome measures were survival, institutionalisation, key worker assessments of avoidable admissions, appropriateness of placement, unmet needs, carer stress and global outcome for patient and carers. Results: Rates of referral to urban teams were double rural rates. Around forty percent of the dementia group had a social worker as assessor and keyworker. The dementia group was significantly more dependent and received more informal and formal care. After six months, only 54% of the dementia group were alive and living outside institutional care, compared to 79% in the functionally ill group. Unplanned admissions to hospitals or homes were rarely judged avoidable by keyworkers. Outcomes for carers were judged poor in 15% of both groups, and 13% and 11% of carers respectively were judged to be under severe stress. Unmet needs were more common in the dementia group, and related principally to residential care and carer respite. A number of measures, including evidence of geographical inequity and identification of unmet needs, provided an important contribution to local policy development. Further work is needed on the validity of keyworker assessments of carer stress, given the findings of the carer interview sub-study.  相似文献   
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我们克隆了大白鼠D1多巴胺基因。序列分析表明,表型克隆的5’端与Monsma等报告的大鼠纹状体D1多巴胺受体的cDNA克隆有所不同。我们又应用聚合酶链反应(PCR)法检查了这种差别是否系由于D1受体基因的不同剪接所造成,但实验结果并不支持这种设想。因此可以认为,Monsma等克隆的D1受体5’端序列值得进一步研究。  相似文献   
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