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81.
Cardiac lipomas are benign neoplasms of the heart and accounts for 8.4% of all primary tumors. They can occur sporadically at any age with no sex preference. The tumor originates mostly in the subendocardium and subepicardium but very rarely within the myocardium. Clinically this tumor is asymptomatic and found incidentally in the vast majority of cases. On occasion large lesions can lead to mechanical obstruction and pericardial effusions if located in the epicardium. Although lipomas can occur at different atrial or ventricular locations, it was never reported at the level of the left atrial appendage (LAA). Usually a mass in the LAA represents a thrombus, however there are few case reports of LAA tumors mainly representing fibroelastomas, myxomas, hemangiomas, and malignant tumors. To our knowledge there are no reported cases of left atrial appendage lipomas (LAAL) in the medical literature. We report the first case of LAAL discovered incidentally on transesophageal echocardiogram during off pump coronary artery bypass grafting.  相似文献   
82.
Even though tumor progression under neoadjuvant chemotherapy is uncommon, its locoregional management remains absolutely unclear. What is the best time for radical surgery or radiotherapy? "Rescue" chemo-radiotherapy could be a suitable radiosensitizing strategy to further reduce tumor progression and allow curative surgery while maintaining systemic therapy.  相似文献   
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Purpose

Our aim was to evaluate in anaplastic thyroid carcinoma (ATC) patients the value of 18F-FDG PET/CT compared with total body computed tomography (CT) using intravenous contrast material for initial staging, prognostic assessment, therapeutic monitoring and follow-up.

Methods

Twenty consecutive ATC patients underwent PET/CT for initial staging. PET/CT was performed again during follow-up. The gold standard was progression on imaging follow-up (CT or PET/CT) or confirmation with another imaging modality.

Results

A total of 265 lesions in 63 organs were depicted in 18 patients. Thirty-five per cent of involved organs were demonstrated only with PET/CT and one involved organ only with CT. In three patients, the extent of disease was significantly changed with PET/CT that demonstrated unknown metastases. Initial treatment modalities were modified by PET/CT findings in 25% of cases. The volume of FDG uptake (≥300 ml) and the intensity of FDG uptake (SUVmax ≥18) were significant prognostic factors for survival. PET/CT permitted an earlier assessment of tumour response to treatment than CT in 4 of the 11 patients in whom both examinations were performed. After treatment with combined radiotherapy and chemotherapy, only the two patients with a negative control PET/CT had a confirmed complete remission at 14 and 38 months; all eight patients who had persistent FDG uptake during treatment had a clinical recurrence and died.

Conclusion

FDG PET/CT appears to be the reference imaging modality for ATC at initial staging and seems promising in the early evaluation of treatment response and follow-up.  相似文献   
85.
Malignant peripheral nerve sheath tumor (MPNST) is an uncommon sarcoma which arises from pluripotent stem cells of the neural crest and differentiates predominantly towards Schwann cells. Low grade spinal MPNST with skeletal muscle differentiation (malignant triton tumor) is vanishingly rare. In this study, we report a case of a 53-year-old female with a homogenously enhancing C2-C4 extradural lesion. The lesion demonstrated a biphasic histologic pattern with a diffusely infiltrating, atypical spindle cell component strongly positive for vimentin and focally positive for S-100. The second component consisted of diffusely scattered clusters of mature skeletal muscle cells which were positive for desmin, fast myosin and muscle specific actin but negative for Myogenin and MyoD-1. The Ki-67 labeling index was low (< 1%) and no necrosis was identified. The present case is remarkable because of its rare location, low grade histology and unusual immunophenotype of the skeletal muscle component, which were not previously described.  相似文献   
86.
Interferon-alpha (IFN-alpha) is recommended in neuroendocrine tumors (NET). Malignant pheochromocytoma and paragangliomas (MPPGLs) constitute a rare subgroup of NET with few treatment options. IFN-alpha efficacy in patients with MPPGLs was evaluated in a single-center retrospective study. Progression-free survival (PFS) was the primary endpoint according to RECIST 1.1 and/or PERCIST 1.0, and response rate, safety, and symptomatic efficacy were secondary endpoints. Fourteen patients received peginterferon alfa-2a (90 to 180 μg/week) or interferon alfa-2b (1.5 to 3 million units × 3/week) at our institution between December 2005 and February 2014 as the first (n = 7), second (n = 3), or subsequent line (n = 4) of treatment. Most of the patients had a slowly progressive disease before IFN-alpha initiation. Eight patients were men (57%); the median age was 44. At the beginning of treatment, 12 patients had progressive disease demonstrated by FDG-PET (n = 9), MIBG (n = 1), or CT scan (n = 2). Most of the patients treated (64%) had metastatic disease limited to or predominantly located in the bones. During IFN-alpha therapy, bone-directed loco-regional treatments were performed in 9 patients (range 1–4). Median PFS was 17.2 months (95% CI [12.1–58.3]). We observed 3 partial metabolic responses, 9 stable diseases, and 2 progressive diseases. No partial response according to RECIST 1.1 was observed. Symptomatic relief of pain, headaches, diarrhea, or sweating occurred in 6 out of 10 symptomatic pts. Most frequent all grade IFN-α-related toxicities were asthenia (n = 10), lymphopenia (n = 7), thrombopenia (n = 6), and anemia (n = 5). Median overall survival was 7.5 years (95% CI [4–NR]). This study suggests symptomatic response and tumor control effect with interferon-alpha in progressive MPPGLs.  相似文献   
87.
Medullary thyroid carcinoma (MTC) is rare in children. MTC is almost always inherited and occurs as part of a multiple endocrine neoplasia type 2A and B, due to germline mutation in the RET proto-oncogene. MTC in the pediatric population is most often diagnosed in the course of a familial genetic investigation. But when the child is the proband, a de novo mutation is most often founded. The main aim is to treat MTC before extrathyroidal extension occurs because when distant metastases are present, it is rarely curable. Treatment is based on total thyroidectomy with cervical lymph node dissection.  相似文献   
88.
The developmentally regulated hemodynamic effects of vasoactive medications have not been well characterized. We used traditional and near-infrared spectroscopy monitoring technologies and investigated the changes in heart rate, blood pressure, common carotid artery (CCA) blood flow (BF), cerebral, renal, intestinal, and muscle regional tissue O2 saturation, and acid-base and electrolyte status in response to escalating doses of vasoactive medications in normotensive anesthetized neonatal piglets. We used regional tissue O2 saturation and CCA BF as surrogates of organ and systemic BF, respectively, and controlled minute ventilation and oxygenation. Low to medium doses of dopamine, epinephrine, dobutamine, and norepinephrine increased blood pressure and systemic and regional BF in a drug-specific manner, whereas milrinone exerted minimal effects. At higher doses, dopamine, epinephrine, and norepinephrine but not dobutamine decreased systemic, renal, intestinal, and muscle BF, while cerebral BF remained unchanged. Epinephrine induced significant increases in muscle BF and serum glucose and lactate concentrations. The findings reveal novel drug- and dose-specific differences in the hemodynamic response to escalating doses of vasoactive medications in the neonatal cardiovascular system and provide information for future clinical studies investigating the use of vasoactive medications for the treatment of neonatal cardiovascular compromise.  相似文献   
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