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101.
Temperament, as indicated by Cloninger's psychobiological model predicts coronary heart disease risk, but its association with autonomic cardiac regulation, a potential mediating mechanism, is unclear. We examined the associations between temperament traits and autonomic cardiac regulation in a resting situation in 798 women and 580 men derived from a population-based sample. After adjustment for age and sex, harm avoidance was associated with lower level of high-frequency (HF) variation, root mean square successive differences (RMSSDs), the percentage of successive R–R intervals >50 ms (pNN50) and higher heart rate (HR) (all p ≤ 0.005), suggesting that harm avoidance is related to low parasympathetic activity. Additional adjustments for behavioral factors attenuated these associations more than the adjustment for biological risk factors. Novelty seeking was associated with higher RMSSD (p = 0.007) and pNN50 (p = 0.012) and lower heart rate (p < 0.001). With adjustment for behavioral risk factors, the associations with RMSSD (p = 0.136) and pNN50 (p = 0.236) attenuated to the null, but adjustment for biological risk factors had little effect. Reward dependence and persistence were unrelated to indices of cardiac regulation.  相似文献   
102.
Renal transplantation is the treatment of choice for many patients with end-stage renal disease. There are a few generally accepted contraindications to transplantation: active infection, malignancy, substance abuse or non-adherence to therapy, chronic illness with life expectancy of less than one year, and poorly controlled psychosis. Potential renal transplant candidates must undergo thorough screening for exclusion of malignant diseases, with an individual approach to each patient. Patients with a history of malignancy might be placed on the waiting list for renal transplantation after a waiting period, which depends on the type of tumor and individual patient characteristics, and there are no signs of tumor. This group of patients require careful surveillance during the waiting time, as well as after transplantation.  相似文献   
103.
104.

Purpose

The psychosocial determinants of prediabetes are poorly understood. The aims of our study were (1) to analyse the association between perceived social support in young adulthood and fasting glucose levels and prediabetes in mid-adulthood in a cohort of healthy Finns, (2) to explore whether body mass index (BMI), inflammation or depression mediate this relationship, (3) and to examine the association between social support trajectory groups and fasting glucose.

Method

A prospective design was used with an analytic sample of 1250 participants aged 3–18 years at baseline (1980) and aged 12–39 years when social support was measured. Fasting glucose and prediabetes were assessed 32 years after baseline. Linear and logistic regression was used to examine the association between social support and the outcome measures. A bootstrapping technique was used to examine mediation effects.

Results

Social support was associated with future glucose levels in women after adjusting for childhood socioeconomic status (SES) and youth depression (β = ?0.136, p = 0.001) and also predicted prediabetes in women after adjusting for childhood SES (β = 1.31, 95 % CI 1.02 to 1.69, p = 0.031). Both associations were attenuated after adjusting for BMI in mid-adulthood. BMI was found to mediate the relationship between social support and prediabetes in women (β for indirect effect β = 0.09, SE = 0.03, CI = 0.03 to 0.16).

Conclusion

Low perceived social support in young adulthood is associated with high fasting glucose and prediabetes in mid-adulthood in women but not men. The association between social support and prediabetes in women can be partly explained by BMI.
  相似文献   
105.
Background: Work stress indicated by effort—reward imbalance is hypothesized to cause autonomic arousal, which, if prolonged or frequent, could contribute to cardiovascular pathology. However, only limited empirical evidence on this mechanism is available. Purpose: This study examined associations between effort-reward imbalance, heart rate (HR), and heart rate variability (HRV). Method: The participants were 457 women and 406 men (mean age 32.3 years) derived from the population-based Young Finns Study. Effort—reward imbalance was defined as the ratio between effort and reward, higher efforts compared to rewards indicating greater imbalance. Results: In age-adjusted regression models, higher effort-reward imbalance was associated with lower HRV, and lower reward was associated with higher HR among women. These associations were not attenuated after additional adjustments for demographic characteristics and coronary risk factors. No significant associations of effort—reward imbalance or its components with HR and HRV were found in men. Conclusion: Our finding of lower HRV and higher HR in young healthy women with high effort—reward imbalance and low rewards provides evidence of a potential mechanism that may link effort-reward imbalance to the development of coronary heart disease (CHD) in women.  相似文献   
106.
107.
The aim of this work is to reproduce the experimentally measured linear dependence of cardiac muscle oxygen consumption on stress–strain area using a model, composed of a three-state Huxley-type model for cross-bridge interaction and a phenomenological model of Ca2+-induced activation. By selecting particular cross-bridge cycling rate constants and modifying the cross-bridge activation model, we replicated the linear dependence between oxygen consumption and stress–strain area together with other important mechanical properties of cardiac muscle such as developed stress dependence on the sarcomere length and force-velocity relationship. The model predicts that (1) the amount of the passenger cross bridges, i.e., cross bridges that detach without hydrolyzing ATP molecule, is relatively small and (2) ATP consumption rate profile within a beat and the amount of the passenger cross bridges depend on the contraction protocol. © 2000 Biomedical Engineering Society. PAC00: 8719Rr, 8719Ff, 8710+e, 8719Hh  相似文献   
108.
The aim here was to employ color tissue velocity imaging (TVI), to test the hypothesis that highly trained endurance athletes exhibit enhanced systolic function of the left ventricular (LV) myocardium both at rest and during combined arm-and-leg exercise in comparison with untrained subjects. For each of the ten elite male (EG) and ten matched control participants (CG), LV dimensions and systolic function were assessed at rest using echocardiography. Subsequently, these subjects exercised continuously on a combined arm-and-leg cycle ergometer for 3 min each at 50, 60, 70, 80, 90 and 100% of VO2max. Oxygen uptake, heart rate, systolic blood pressure (SBP) and peak contraction systolic velocities of the LV myocardium (PSV) were recorded in the end of each level. At rest, the trained and untrained groups differed with respect to LV dimensions, but not systolic function. At 60–100% VO2max, the EG group demonstrated both higher PSV and SBP. The observation that the EG athletes had higher PSV than CG during exercise at 60–100% VO2max, but not at rest or at 50% of VO2max, suggested an enhanced systolic capacity. This improvement is likely to be due to an enhanced inotropic contractility, which only becomes apparent during exercise.  相似文献   
109.
BACKGROUND: There has been rapid growth in the technical and physiologic demands made on skaters who perform more and more difficult jumps, spins, lifts, throws, and free skating movements. PURPOSE: To investigate the frequency of injuries and overuse syndromes in elite junior skaters. STUDY DESIGN: Questionnaire. METHODS: During four consecutive Junior World Figure Skating Championships and the Croatia Cup, we interviewed 236 female and 233 male skaters by questionnaire to determine the frequency of injuries and overuse syndromes. RESULTS: Fifty-nine of the female skaters (25%) and 65 of the male skaters (27.9%) reported sustaining acute injuries; 101 female (42.8%) and 106 male (45.5%) skaters reported overuse syndromes. Low back pain was reported by 19 female and 23 male skaters. The most frequent acute injury was ankle sprain. In singles female skaters, the most frequent overuse injury was stress fracture (19.8%), followed by jumper's knee (14.9%). In singles male skaters, jumper's knee (16.1%) was the most frequent injury, followed by Osgood-Schlatter disease (14.2%). More than 50% of injuries in young singles figure skaters involved overuse syndromes. Pairs skaters and ice dance skaters had a higher risk of acute injury than overuse syndrome because of falls from lifts and throw jumps. CONCLUSIONS: Programs to improve postural alignment, flexibility, and strength, especially during the asynchronous period of bone and soft tissue development, should be instituted to prevent and reduce overuse syndromes.  相似文献   
110.

Context

The European Association of Urology (EAU) Guidelines Panel on Upper Urinary Tract Urothelial Carcinoma (UTUC) has prepared updated guidelines to aid clinicians in the current evidence-based management of UTUC and to incorporate recommendations into clinical practice.

Objective

To provide an overview of the EAU guidelines on UTUC as an aid to clinicians.

Evidence acquisition

The recommendations provided in the current guidelines are based on a thorough review of available UTUC guidelines and articles identified following a systematic search of Medline. Data on urothelial malignancies and UTUC were searched using the following keywords: urinary tract cancer; urothelial carcinomas; upper urinary tract, carcinoma; renal pelvis; ureter; bladder cancer; chemotherapy; ureteroscopy; nephroureterectomy; adjuvant treatment; instillation; recurrence; risk factors; and survival. References were weighted by a panel of experts.

Evidence synthesis

Owing to the rarity of UTUC, there are insufficient data to provide strong recommendations (ie, grade A). However, the results of recent multicentre studies are now available, and there is a growing number of retrospective articles in UTUC. The 2017 tumour, node, metastasis (TNM) classification is recommended. Recommendations are given for diagnosis and risk stratification, as well as for radical and conservative treatment; prognostic factors are also discussed. A single postoperative dose of intravesical mitomycin after radical nephroureterectomy reduces the risk of bladder tumour recurrence. Kidney-sparing management should be offered as a primary treatment option to patients with low-risk tumours and two functional kidneys.

Conclusions

These guidelines contain information on the management of individual patients according to a current standardised approach. Urologists should take into account the specific clinical characteristics of each patient when determining the optimal treatment regimen, based on the proposed risk stratification of these tumours.

Patient summary

Urothelial carcinoma of the upper urinary tract is rare, but because 60% of these tumours are invasive at diagnosis; appropriate diagnosis and management is most important. We present recommendations based on current evidence for optimal management.  相似文献   
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