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Mesenchymal hamartoma of the liver is a cystic benign liver mass occurring in children. Diagnostic confusion with hepatoblastoma may arise when alpha-feto-protein (AFP) level is elevated. We report an extremely rare case of mesenchymal hamartoma in an 11-month-old boy. Serum AFP was elevated and fine-needle aspiration biopsy suggested the lesion as hepatoblastoma, so he received preoperative chemotherapy. At the end of the preoperative chemotherapy, the tumor size and AFP level decreased. A right hepatectomy was performed. The pathologic examination of the specimen revealed mesenchymal hamartoma. Mesenchymal hamartoma of the liver with increased serum AFP levels may mimic hepatoblastoma if a cytological examination samples only the hepatocellular component of mesenchymal hamartoma. According to our knowledge, this is the first case of the mesenchymal hamartoma of the liver, which showed reduction in serum levels of AFP and involution of the tumor size by preoperative chemotherapy.  相似文献   
107.

Introduction  

The posterior reversible encephalopathy syndrome (PRES) is a recently proposed cliniconeuroradiological entity. The most common causes of PRES are hypertensive encephalopathy, eclampsia, cyclosporin A neurotoxicity, and the uremic encephalopathy. On magnetic resonance imaging (MRI) studies, edema has been reported in a relatively symmetrical pattern, typically in the subcortical white matter and occasionally in the cortex of the posterior circulation area of the cerebrum.  相似文献   
108.
Phenylketonuria is a genetic metabolic disorder resulting in phenylalanine accumulation in blood. Phenylacetate, which is an abnormal phenylalanine metabolities, was hypothesized to have anticancer activity. Two-years-old boy was diagnosed with classical phenylketonuria because of mental motor retardation. When the patient was 9-year-old, he developed acute myeloblastic leukemia. Here, we present the case with phenylketonuria and acute myeloblastic leukemia because of its extreme rarity.  相似文献   
109.

PURPOSE

We aimed to evaluate the efficacy of multidetector computed tomography (CT) imaging in diagnosis of pleural exudates and transudates using attenuation values.

MATERIALS AND METHODS

This retrospective study included 106 patients who were diagnosed with pleural effusion between January 2010 and June 2012. After the patients underwent chest CT, thoracentesis was performed in the first week. The attenuation values of the pleural effusions were measured in all patients.

RESULTS

According to Light’s criteria, 30 of 106 patients with pleural effusions had transudates, and the remaining patients had exudates. The Hounsfield unit (HU) value of the exudates (median, 12.5; range, 4–33) was significantly higher than that of the transudates (median, 5; range, 2–15) (P = 0.001). Additionally, when evaluated by disease subgroups, congestive heart failure and empyema were predictable in terms of median HU values of the pleural effusions with high and moderate sensitivity and specificity values (84.6% and 81.2%, respectively; 76.9% and 66.7%, respectively). Compared with other patients, the empyema patients had significantly more loculation and pleural thickening.

CONCLUSION

CT attenuation values may be useful in differentiating exu-dates from transudates. Although there is an overlap in most effusions, exudate can be considered when the CT attenuation values are >15 HU. Because of overlapping HU values, close correlation with clinical findings is essential. Additional signs, such as fluid loculation and pleural thickness, should be considered and may provide further information for the differentiation.Pleural effusion is a common clinical problem; indeed, it can arise from many diseases (1, 2). The first step in assessing a pleural effusion is to decide whether the pleural fluid is a transudate or an exudate (3). Transudate is caused by imbalances in hydrostatic and oncotic forces. It results from diseases such as heart failure, kidney failure, and cirrhosis. However, an exudate occurs when local factors influencing the accumulation of pleural fluid are altered. Exudates can be caused by clinical conditions such as pneumonia, malignancy, and thromboembolism (4).Although clinical and radiological findings may provide significant evidence about the cause(s) of pleural effusion(s), it may still be necessary to evaluate some cases with diagnostic thoracentesis (4, 5). Clinically, exudative effusion can be successfully separated from transudative effusion using Light’s criteria. The nature of the pleural effusion is based on diagnostic thoracentesis (1, 2). However, computed tomography (CT) can be used to evaluate the nature of pleural effusions to avoid the complications of thoracentesis (6, 7). Features such as pleural nodules, pleural thickening, loculation, extrapleural fat tissue thickness, and effusion density can be evaluated by CT to discriminate between exudates and transudates (8). Only two reported studies have examined CT attenuation values in patients with pleural effusions (9, 10); these showed different attenuation values for evaluation of pleural effusions.The aim of the present study was to evaluate the efficacy of multidetector CT (MDCT) images in diagnosing pleural exudates and transudates using attenuation values.  相似文献   
110.

Objective.

Urotensin II is a potent vasoactive peptide that has been implicated in the pathophysiology of many diseases. There is no study reporting the role and level of this peptide in recipients of kidney transplant. So we aimed to study the plasma levels of urotensin II in this group of patients.

Methods.

Plasma urotensin II levels were analyzed in 110 subjects, who were divided into three groups: group 1 (35 kidney transplant recipients), group 2 (36 patients with chronic kidney disease), and group 3 (39 healthy controls).

Results.

Analysis of logarithmic transformation of urotensin II, i.e. log (urotensin II × 1000) levels, with a one-way analysis of variance yielded a P value of 0.001. Post-hoc analysis showed significantly higher log (urotensin II × 1000) levels in group 1 than groups 2 and 3 (P = 0.001 and 0.017, respectively). One of the important features of the subjects of this group was that they were taking immunosuppressive drugs because of renal transplantation.

Conclusions.

High urotensin II levels in recipients of kidney transplants could be drug-related (immunosuppressive drugs) and may be of practical importance that may be used to improve the long-term outcome of the patients.  相似文献   
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