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571.
PurposeThis study aimed to evaluate iron levels in cardiac and hepatic tissues using magnetic resonance imaging (MRI) T2?.MethodsCardiac and hepatic MRI was performed for 93 patients with β-thalassemia major.ResultsCardiac T2? was in the range of 2.9–56.6 ms. Myocardial siderosis was detected in 44% of patients; 25 patients had moderate and severe siderosis with serum ferritin level (SFL) of 576–10,284 ng/ml. There was a significant correlation between SFL and cardiac T2? (p<.001).ConclusionsThe effective role of MRI as a noninvasive producible method in measurement of iron concentration in tissues is not accessible with conventional techniques.  相似文献   
572.
Wound healing is a dynamic and complex biological process, which requires coordinated events including haemostasis, inflammation, proliferation, revascularisation and remodelling. Impaired wound healing is a common problem that occurs in both community and hospital settings. Various experimental and clinical studies have evaluated different modalities for the treatment of topical wounds, such as sugar, antibiotics, honey and phytotherapies; also statins have diverse pleiotropic effects that have been suggested to be useful to improve wound healing. Data derived from both animal and human studies showed that statins especially atorvastatin, simvastatin and pravastatin can accelerate the wound-healing process. However, further high-quality and evidence-based studies are needed to address the best statin drug, appropriate dose, the best administration route, duration of treatment and to determine correlation between pleiotropic effects of statins and their probable clinical benefits.  相似文献   
573.
Traditional methods of reconstruction of the hair-bearing scalp can provide incorrect directional hair growth and may require secondary procedures to complete. We present a case of reconstruction of the anterior hairline after tumour resection in an infant. Lessons learned from the case have led to a novel method for a single stage reconstruction of the anterior hairline using pedicled superficial artery flaps.  相似文献   
574.
575.

Purpose

X-ray imaging is widely used for guiding minimally invasive surgeries. Despite ongoing efforts in particular toward advanced visualization incorporating mixed reality concepts, correct depth perception from X-ray imaging is still hampered due to its projective nature.

Methods

In this paper, we introduce a new concept for predicting depth information from single-view X-ray images. Patient-specific training data for depth and corresponding X-ray attenuation information are constructed using readily available preoperative 3D image information. The corresponding depth model is learned employing a novel label-consistent dictionary learning method incorporating atlas and spatial prior constraints to allow for efficient reconstruction performance.

Results

We have validated our algorithm on patient data acquired for different anatomy focus (abdomen and thorax). Of 100 image pairs per each of 6 experimental instances, 80 images have been used for training and 20 for testing. Depth estimation results have been compared to ground truth depth values.

Conclusion

We have achieved around \(4.40\,\%\,\pm \,2.04\) and \(11.47\,\%\,\pm \,2.27\) mean squared error on abdomen and thorax datasets, respectively, and visual results of our proposed method are very promising. We have therefore presented a new concept for enhancing depth perception for image-guided interventions.
  相似文献   
576.
Background: Intravenous thrombolysis improves outcomes of stroke patients. The immediate response to thrombolysis is variable and few studies attempted to identify predictors of major neurological improvement (MNI) 24 h following thrombolysis. Our objective is to determine predictors of MNI 24 h following thrombolysis. Methods: We reviewed the prospective database of patients treated through our telestroke network and at our institution between November 2008 and June 2012. We included all patients who received IV t-PA and had a 24-h NIHSS score available. Similar to previous studies, we defined MNI as a reduction in NIHSS score by ≥8 points, or a score of 0 or 1 at 24 h. Demographics, risk factors, time to treatment, and clinical and laboratory data, were compared between MNI present or absent. Baseline predictors were compared using t- and Fisher's exact tests, and outcomes using multivariate logistic regression analysis. Results: Out of 316 patients, 306 had 24-h NIHSS scores and 38% of them experienced MNI. Patients with MNI were less likely to be older than 80 years (16% vs. 29%, p = 0.008) and to have atrial fibrillation (9% vs. 24%, p = 0.001) compared to those without; we found no other predictors of MNI. After adjusting for baseline demographics and risk factors, age less than 80 years (OR = 1.9, 95% CI 1.1–3.6) and absence of atrial fibrillation (OR = 3.0, 95% CI: 1.4–6.2) predicted MNI. Conclusion: Major neurological improvement within 24 h after thrombolysis is more likely in younger patients and those without atrial fibrillation.  相似文献   
577.
Glucocorticoids have a major effect on food intake that is underappreciated, although the effects of glucocorticoids on metabolism and abdominal obesity are quite well understood. Physiologically appropriate concentrations of naturally secreted corticosteroids (cortisol in humans, corticosterone in rats) have major stimulatory effects on caloric intake and, in the presence of insulin, preference. We first address the close relationship between glucocorticoids and energy balance under both normal and abnormal conditions. Because excess caloric intake is stored in different fat depots, we also address the systemic effects of glucocorticoids on redistribution of stored energy preponderantly into intraabdominal fat depots. We provide strong evidence that glucocorticoids modify feeding and then discuss the role of insulin on the choice of ingested calories, as well as suggesting some central neural pathways that may be involved in these actions of glucocorticoids and insulin. Finally, we discuss the evolutionary utility of these actions of the stress hormones, and how dysregulatory effects of chronically elevated glucocorticoids may occur in our modern, rich societies.  相似文献   
578.
579.
Wang  Peiqi  Hu  Jun  Ghadermarzi  Shadi  Raza  Ali  O’Connell  Douglas  Xiao  Amy  Ayyaz  Faraz  Zhi  Min  Zhang  Yuanqi  Parekh  Nimisha K.  Lazarev  Mark  Parian  Alyssa  Brant  Steven R.  Bedine  Marshall  Truta  Brindusa  Hu  Pinjin  Banerjee  Rupa  Hutfless  Susan M. 《Digestive diseases and sciences》2018,63(10):2703-2713
Digestive Diseases and Sciences - Cigarette smoking is thought to increase the risk of Crohn’s disease (CD) and exacerbate the disease course, with opposite roles in ulcerative colitis (UC)....  相似文献   
580.
Atrial fibrillation (AF) is the most common supraventricular arrhythmia, and it corresponds highly with exercise intensity. Here, we induced AF in mice using acetylcholine (ACh)-CaCl2 for 7 days and aimed to determine the appropriate exercise intensity (no, low, moderate, high) to protect against AF by running the mice at different intensities for 4 weeks before the AF induction by ACh-CaCl2. We examined the AF-induced atrial remodeling using electrocardiogram, patch-clamp, and immunohistochemistry. After the AF induction, heart rate, % increase of heart rate, and heart weight/body weight ratio were significantly higher in all the four AF groups than in the normal control; highest in the high-ex AF and lowest in the low-ex (lower than the no-ex AF), which indicates that low-ex treated the AF. Consistent with these changes, G protein-gated inwardly rectifying K+ currents, which were induced by ACh, increased in an exercise intensity-dependent manner and were lower in the low-ex AF than the no-ex AF. The peak level of Ca2+ current (at 0 mV) increased also in an exercise intensity-dependent manner and the inactivation time constants were shorter in all AF groups except for the low-ex AF group, in which the time constant was similar to that of the control. Finally, action potential duration was shorter in all the four AF groups than in the normal control; shortest in the high-ex AF and longest in the low-ex AF. Taken together, we conclude that low-intensity exercise protects the heart from AF, whereas high-intensity exercise might exacerbate AF.  相似文献   
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