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861.
Leiomyosarcomas are uncommon malignant neoplasms that account for less than 1 % of all cancers. A primary retropharyngeal leiomyosarcoma is an extremely rare neoplasm that has not been reported in the English-language literature. Herein, we report a case of a 46-year-old male patient with leiomyosarcoma showing focal rhabdomyosarcomatous differentiation arising from the retropharynx and describe the radiological imaging findings and pathological features.  相似文献   
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864.
OBJECTIVE: The myocardial performance index (MPI) enables noninvasive estimation of combined systolic and diastolic function. The only diastolic function parameter used in the index is the isovolumic relaxation time (IRT). We assessed the impact of shortened IRT in restrictive filling pattern on MPI. METHODS: The MPI was defined as the sum of the isovolumic contraction time (ICT) and the IRT divided by the ejection time (ET), and was calculated in 13 controls (group 1), and 39 patients with ischemic heart disease with left ventricular systolic dysfunction (ejection fraction<50%). The patients were classified into two groups according to mitral early filling deceleration time (DT): group 2 with DT>140 ms (n = 20), and group 3 with DT < or =140 ms (n = 19). RESULTS: The ICT was longer and the ET was shorter in group 2 and group 3 than in group 1. The ICT and ET were not different in group 2 and group 3. The IRT was longer in group 2 (130+/-23 ms) compared to group 1 (82+/-10 ms, p<0.001) and group 3 (85+/-19 ms, p<0.001), but did not differ between group 1 and group 3. The MPI was higher in group 2 and group 3 compared to group 1 (0.79+/-0.25 and 0.65+/-0.19 vs 0.42+/-0.08, p<0.001 and p<0.001; respectively). However, it was lower in group 3 than in group 2 (p=0.03) due to significantly shortened IRT. CONCLUSION: Shortened IRT in patients with restrictive filling pattern results in reduction of the MPI. Therefore, the MPI may not reflect true level of ventricular dysfunction in these patients.  相似文献   
865.

Introduction

Discrimination of stroke and stroke mimics is problematic in young patients. The aim of the study was to determine whether arterial ischemic stroke and stroke mimics can be differentiated via the red cell distribution width (RDW) value in young patients.

Material and methods

In this retrospective cross-sectional study, a total of 236 patients hospitalized at the neurology ward were investigated. The patients were divided into 3 groups: the 1st group included young stroke patients, the 2nd group included patients with epilepsy, and the 3rd group included patients with multiple sclerosis (MS). Complete blood count and computed tomographic brain imaging tests were performed in all patients, and magnetic resonance imaging was done when necessary.

Results

A total of 236 patients were included in this study. Ninety-five (40%) patients were young stroke patients, 71 (30%) had epilepsy and 70 (30%) had MS. The mean RDW values of young patients with stroke were significantly higher than patients with epilepsy or MS (14.9 ±1.2, 13.3 ±1.2, 13.4 ±0.6, p < 0.0001, respectively). The diagnostic power of RDW in the differentiation of patients with stroke is good (area under the curve (AUC) = 0.89). When an RDW cut-off value of 14.05% is accepted for differentiating young patients with stroke from other disorders, the sensitivity, specificity, positive predictive and negative predictive values were 73.7%, 87.9%, 6.1 and 0.043, respectively.

Conclusions

Red cell distribution width is a promising, rapid, easy and inexpensive parameter to distinguish young stroke from stroke mimics (such as epilepsy and MS) in young patients.  相似文献   
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867.
Although there are many studies demonstrating increased trunk activation under unstable conditions, it is not known whether this increased activation would translate into meaningful trunk strength with a prolonged training program. Additionally, while balance-training programs have been shown to improve stability, their effect on specific joint proprioception is not clear. Thus the objective of this study was to examine training adaptations associated with a 10-week instability-training program. Participants were tested pre- and post-training for trunk extension and flexion strength and knee proprioception. Forty-three participants participated in either a 10-week (3 days per week) instability-training program using Swiss balls and body weight as resistance or a control group (n = 17). The trained group increased (p < 0. 05) trunk extension peak torque/body weight (23.6%) and total work output (20.1%) from pre- to post-training while the control group decreased by 6.8% and 6.7% respectively. The exercise group increased their trunk flexion peak torque/body weight ratios by 18.1% while the control group decreased by 0.4%. Knee proprioception (combined right and left joint repositioning) improved 44.7% from pre- to post-training (p = 0.0006) and persisted (21.5%) for 9 months post-training. In addition there was a side interaction with the position sense of the right knee at 9 months showing 32.1% (p = 0.03) less deviation from the reference angle than the right knee during pre-testing. An instability-training program using Swiss balls with body weight as resistance can provide prolonged improvements in joint proprioception and core strength in previously untrained individuals performing this novel training stress which would contribute to general health.

Key points

  • Although traditional free weight resistance exercises have been recommended as most beneficial for improving strength and power in athletes (Behm et al., 2010b), an IT program using Swiss balls and body weight as a resistance may provide an alternative starting point for the sedentary untrained population.
  • As it is well documented that force or strength is decreased when unbalanced (Behm et al., 2010b) and balance-training programs improve balance (Behm and Kean 2006), this type of instability RT program can provide significant adaptations to improve trunk strength especially with the untrained.
  • This type of training should also be incorporated into a new program as the improvements in joint proprioception may help protect from joint injuries over a protracted period.
  • The finding that improved joint proprioception persists for months after training should be emphasized to those individuals whose training is regularly or inconsistently interrupted.
Key words: Instability resistance training, stability, back, abdominals  相似文献   
868.
There is a lack of information about the role of poultry, specifically chicken, in transmission of Escherichia coli (E. coli) O157 and subsequent human illnesses. This study was therefore aimed at investigating the presence of E. coli O157 and its virulence genes in various samples collected from broiler chickens and humans in Eastern Turkey by culture, immunomagnetic separation (IMS), and polymerase chain reaction (PCR). The genetic relationship between broiler and human isolates was also examined by pulsed-field gel electrophoresis (PFGE). In the PCR analysis of sorbitol-negative isolates, E. coli O157 was identified in 0.1% (1/1000) and 0.4% (4/1000) of the liver and cecum samples of broiler chickens, respectively. On the other hand, none of the carcass samples were determined to be positive for E. coli O157. Overall, the results indicated that 12% (3/25) of the flocks were positive for E. coli O157. The differences between the flocks in terms of the positivity were determined to be statistically significant (p<0.001). Ten (2.7%) of 367 human stool samples were also positive for E. coli O157 in the PCR examination. None of the broiler and human E. coli O157 isolates possessed H7, shigatoxins 1-2, or enterohemolysin genes, whereas all the broiler isolates and one of the human isolates were positive for intimin gene. In the PFGE analysis, a total of eight different profiles (four from broiler and four from human isolates) were observed. However, there were no genetic relationships between broiler and human E. coli O157 isolates. It can be concluded that more detailed studies are needed in poultry to better understand the role of these species in the epidemiology of E. coli 0157 infections in humans.  相似文献   
869.

Purpose

The objective of this study was to investigate perinatal outcome in cases of increased nuchal translucency (NT) with or without cystic hygroma (CH), and to determine whether first-trimester CH engenders a greater risk than simple increased NT.

Methods

In this retrospective study, data from singleton pregnancies in which fetal NT was found to be 3 mm or more at the 11 + 0 to 13 + 6 weeks scan were reviewed. Cases were classified into two groups, namely ‘CH’ and ‘increased NT’.

Results

Of the 76 cases with increased NT, 30 (39.4 %) presented with CH. NT measurement was significantly higher in the CH group (7.25 vs. 3.5 mm, p < 0.001). Abnormal fetal karyotype, major chromosomal anomalies in chromosomally normal fetuses, and adverse outcome were significantly more frequent in the CH group as compared with the increased NT group (p = 0.019, p = 0.021, and p = 0.001, respectively). Regression analysis revealed that NT thickness was the only significant variable in the prediction of chromosomal defect and/or major congenital anomaly (OR 2.05, 95 % CI 1.23–3.42, p = 0.005).

Conclusion

Cystic hygroma results in poorer outcome due to higher NT measurement, and the thickness of NT rather than the presence of septa should be the mainstay of prenatal counseling in cases of increased NT in the first trimester.  相似文献   
870.
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