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991.
An estimated 25–60% of adults with sickle cell disease (SCD) are unemployed. Factors contributing to the high unemployment rate in this population are not well studied. With the known risk of cognitive deficits associated with SCD, we tested the hypothesis that unemployment is related to decrements in intellectual functioning. We conducted a retrospective chart review of 50 adults with sickle cell anemia who completed cognitive testing, including the Wechsler Adult Intelligence Scale–IV, as part of standard care. Employment status was recorded at the time of testing. Medical variables examined as possible risk factors for unemployment included disease phenotype, cerebral infarction, and pain frequency. The mean age of the sample was 30.7 years (range = 19–59); 56% were women. Almost half of the cohort (44%) were unemployed. In a multivariate logistic regression model, lower IQ scores (odds ratio = 0.88; p = .002, 95% confidence interval, CI [0.82, 0.96]) and lower educational attainment (odds ratio = 0.13; p = .012, 95% CI [0.03, 0.65]) were associated with increasing odds of unemployment. The results suggest that cognitive impairment in adults with sickle cell anemia may contribute to the risk of unemployment. Helping these individuals access vocational rehabilitation services may be an important component of multidisciplinary care.  相似文献   
992.
Bulletin of Environmental Contamination and Toxicology - Neonicotinoid insecticides are highly water soluble with relatively long half-lives, which allows them to move into and persist in aquatic...  相似文献   
993.
Fructose-fed rats are protected against ischemia/reperfusion injury   总被引:1,自引:0,他引:1  
This study examines the relationship between insulin resistance (IR) induced by fructose feeding (FF) and susceptibility to myocardial ischemia/reperfusion injury (MI/R). Six-week-old male Sprague-Dawley rats were randomized into control (CON; n = 59) or FF (n = 58) groups. After 4 weeks, rats were further randomized into one of the following groups: placebo, ischemic preconditioning (IPC), 5-hydroxydecanoic acid (5-HD) (10 mg/kg), or 5-HD + IPC. Moreover, to determine the role of fructose, a second model of IR (Zucker obese) and rats fed fructose diet for 3 days (FF-3) were also subjected to MI/R. In all experiments, rats were subjected to 30 min of myocardial ischemia and 4 h of reperfusion. In rats randomized to placebo, infarct size was significantly reduced by FF (24 +/- 5%) compared with CON (54 +/- 1%, p < 0.05). Pretreatment with 5-HD did not alter the infarct size in CON (45 +/- 5%) but inhibited the protection afforded by FF (53 +/- 7%). IPC reduced the infarct size to an equivalent level in both groups, whereas 5-HD administration prior to IPC blunted the IPC effect. In Zucker obese rats, infarct size was significantly larger (57 +/- 4%) compared with lean controls (37 +/- 4%, p < 0.05). In FF-3 rats, infarct size was also decreased (20 +/- 2%, p < 0.01) compared with CON. This study suggests that fructose feeding affords protection against MI/R that is related to or mimics preconditioning. This protection is not consistent with other models of IR and is likely related to the fructose diet itself.  相似文献   
994.
995.

Background

Intermittent claudication is the most common symptom of peripheral arterial disease. Previous research has suggested that extracorporeal shockwave therapy (ESWT) may induce angiogenesis in treated tissue. The objective of this feasibility pilot trial was to assess the safety, tolerability, and efficacy of ESWT as a novel treatment.

Methods

Patients with unilateral claudication were randomized to receive ESWT or sham treatment to the calf muscle three times per week for 3 weeks. Primary outcomes were pain-free walking distance (PFWD) and maximum walking distance (MWD). Secondary outcomes included safety and tolerability of ESWT treatment, ankle-brachial index before and after exercise, and quality of life assessed using generic (36-Item Short Form Health Survey, EuroQol-5 Dimension 3-Level) and disease-specific (Vascular Quality of Life) instruments. Participants were assessed at baseline and 4, 8, and 12 weeks after treatment. Feasibility outcomes included recruitment and attendance rates for treatment and follow-up.

Results

Thirty patients were recruited in total. Statistically significant (P < .05) improvements at all time points were observed in the active treatment group for both MWD and PFWD compared with the sham treatment group. PFWD improved by 276% in the active group and MWD improved by 167% in the active group at 12 weeks after treatment. There were no immediate or delayed treatment safety concerns or documented adverse effects of treatment with ESWT in this trial.

Conclusions

ESWT is safe and well tolerated when it is applied to the calf and demonstrated significant improvements in walking distances. Current conservative management of intermittent claudication includes supervised exercise. The early results with ESWT as an alternative, noninvasive treatment option show great potential. The mechanism of action, durability of the clinical effect, and cost-effectiveness of ESWT for claudication require further investigation.  相似文献   
996.
997.
Intravascular ultrasound has emerged as the preferred imaging modality for the characterization of atherosclerotic plaque within the coronary arteries. Ultrasonic imaging reveals the presence of more extensive atheroma than suggested by conventional angiography in patients with coronary artery disease. The ability to precisely quantify atheroma volume in an arterial segment at different time points provides the unique opportunity to investigate the factors that influence the natural history of atheroma progression. Accordingly, serial intravascular ultrasound has been incorporated into a number of clinical trials that have evaluated the impact of medical therapies that modify established risk factors and novel pathological targets. This article will review the increasing role of imaging modalities in the assessment of atherosclerosis and factors that influence its natural history.  相似文献   
998.
999.
This strategic plan translates the HCHP vision statement into a working plan for one major clinical condition--asthma in children. It is a working plan for clinicians and managers across specialties and levels. The results of the projects will improve in a measurable way significant clinical practice and outcomes, in keeping with the FY 1993 strategic goals.  相似文献   
1000.
Isocapnic dry gas hyperventilation provokes hyperpnea-induced bronchoconstriction in guinea pigs by releasing tachykinins from airway sensory C-fiber neurons. It is unknown whether dry gas hyperpnea directly stimulates C-fibers to release tachykinins, or whether this physical stimulus initiates a mediator cascade that indirectly stimulates C-fiber tachykinin release. We tested the hypotheses that mucosal hypothermia and/or hyperosmolarity--physical consequences of airway heat and water loss imposed by dry gas hyperpnea--can directly stimulate C-fiber tachykinin release. Neurons isolated from neonatal rat dorsal root ganglia were maintained in primary culture for 1 wk. Cells were then exposed for 30 min at 37 degrees C to graded concentrations of NaCl, mannitol, sucrose, or glycerol (0-600 mOsm) added to isotonic medium, or to isotonic medium at 25 degrees C without or with 462 mOsm mannitol added. Fractional release of substance P (SP) was calculated from supernatant and intracellular SP contents following exposure. Hyperosmolar solutions containing excess NaCl, mannitol, or sucrose all increased fractional SP release equivalently, in an osmolarity-dependent fashion. In marked contrast, hypothermia had no effect on fractional SP release under isotonic or hypertonic conditions. Thus, hyperosmolarity, but not hypothermia, can directly stimulate tachykinin release from cultured rat sensory C-fibers. The lack of effect of glycerol, a solute which quickly crosses cell membranes, suggests that neuronal volume change represents the physical stimulus transduced by C-fibers during hyperosmolar exposure.  相似文献   
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