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51.
BACKGROUND: Ipsilateral salivary gland tumors of different histologic types are rare and make up less than 0.3% of all salivary gland neoplasms. Only nine cases of synchronous benign and malignant ipsilateral parotid gland tumors have been described in the literature. METHODS: Two additional cases of synchronous benign and malignant neoplasms in the parotid gland are reported and discussed with a review of literature. RESULTS: Our first case describes a pleomorphic adenoma and a salivary duct carcinoma, an entity not previously reported in the literature. The second case documents the most common benign and malignant ipsilateral parotid gland neoplasm reported in this case series, a Warthin's tumor and a mucoepidermoid carcinoma. CONCLUSIONS: Synchronous salivary gland tumors exhibiting both benign and malignant components are uncommonly observed, with only nine cases published to date. We describe two additional cases of a synchronous benign and malignant ipsilateral parotid gland tumor.  相似文献   
52.
We report a case of primary splenic T-cell lymphoma that posed difficult problems in differential diagnosis with erythrophagocytic T-gamma lymphoma and inflammatory pseudotumor of the spleen. The need for immunophenotypic and molecular studies for establishing the correct diagnosis and the importance of early detection and treatment, is emphasized in the light of the relatively good prognosis of splenic lymphoma, diagnosed in the early stages of disease.  相似文献   
53.
A 15-year-old “asthmatic” found to have a pleomorphic adenoma of the trachea was treated by staged CO2 laser excision Primary tracheal tumors, the clinicopathologic features of mixed tumor in this rare location, and therapeutic options are briefly reviewed Immunohistochemical stains for cytokeratin, S-100 protein, and glial fibrillary acidic protein are reliable methods of evaluating component cell types in pleomorphic adenoma, but immunohistochemical evidence has not resolved the issue of tumor histogenesis.  相似文献   
54.
A case of a 72-year-old man with multiple mixed tumor (pleomorphic adenoma) with its clinicopathological study was reported. In this patient, the first tumor appeared in the right parotid gland area of his right maxillary region at the age of 20. After resection of the primary tumor, the tumor recurred at the same site; he was operated on 2 more times at the ages of 21 and 45. Additionally, other new tumors appeared on the skin of the right ear lobe at the age of 48 and on the right temporal region at the age of 51. The most recent tumor reappeared in his right parotid gland area at the age of 60. All the tumors were examined by light microscope and electron microscope and the diagnosis of multiple mixed tumor (pleomorphic adenoma) was established.  相似文献   
55.
Recurrent pleomorphic adenoma of the parotid gland   总被引:1,自引:0,他引:1  
BACKGROUND: Surgery of recurrent pleomorphic adenoma presents an increased risk of facial nerve injury and a considerable re-recurrence rate. METHODS: A series of 33 patients with first recurrence of pleomorphic adenoma of the parotid gland was analyzed. The data were derived from medical records as well as from interviews and clinical examinations of all living patients. Histologic material of the initial and recurrent tumor were reviewed. RESULTS: Multifocal recurrence and carcinoma in pleomorphic adenoma were observed in 73% and 9% of patients, respectively. The incidence of permanent partial facial nerve injury after surgery was 23% in patients with initial enucleation and 14% in those with initial superficial parotidectomy (including 1 patient with facial nerve resection and 1 patient with a partial facial paresis before recurrence surgery). A subsequent recurrence occurred in 6 patients, all with initial enucleation after a mean time interval of 9 years. CONCLUSIONS: The preservation of the facial nerve was possible in all but 1 patient treated for the first recurrence with a relatively low rate of permanent partial facial paresis because of the use of the operating microscope and facial nerve monitor. To evaluate the re-recurrence rate, a follow-up of at least 10 years is necessary.  相似文献   
56.
OBJECTIVES: Surgery of recurrent pleomorphic adenoma (RPA) is known to lead to a high facial nerve complication rate. The efficacy of the continuous facial nerve monitoring (CFNM) technique remains to be proven in RPA surgery. The goal was thus to evaluate facial nerve palsy rates and the recovery period after parotidectomy for RPA using CFNM by way of continuous electromyography and to compare these rates and the operation time with those of patients who had undergone surgery without facial nerve monitoring. DESIGN: Cohort study. PATIENTS: Forty-seven patients were referred for RPA (1981-2003). Among them, 32 (18 unmonitored and 14 monitored) patients displayed no preoperative facial palsy, and histologic analyses revealed evidence of recurrence. The operation time and the extent and duration of postoperative facial nerve palsy were examined in both groups (monitored vs. unmonitored). Both groups had a similar clinical appearance distribution. RESULTS: Facial nerve paralysis was estimated using the House-Brackmann grading scale. CFNM reduced the intensity of facial nerve paralysis independently of the kind of surgery performed. The complete deficit rates were 0% for the monitored group and 5.6% for the unmonitored group. Postoperative facial nerve paralysis was significantly lower (P = .01) in the monitored group than in the unmonitored group. CFNM improved the duration of facial paralysis (P = .001) in the monitored group. The operation time was significantly lower in the monitored group than in the unmonitored group (P = .001). CONCLUSIONS: Routine use of CFNM during RPA surgery improves the surgical outcome. The facial nerve deficit can be reduced, and the recovery of facial nerve function is faster.  相似文献   
57.
The molecular genetic basis and the tumorigenic mechanism of pleomorphic xanthoastrocytoma (PXA) still remain to be elucidated. The amplification of the mdm2 gene and accumulation of the MDM2 protein, which is considered to be one of the major cellular regulators of p53-mediated cell growth control, were studied in eight specimens of PXA obtained from five patients. All of the PXA samples showed at least focal immunopositivity for MDM2. However, none of the samples showed mdm2 gene amplification. These results suggest that accumulation of MDM2 without gene amplification may be one of the major molecular events occurring in the tumorigenesis of PXA.  相似文献   
58.
OBJECTIVES: To present the clinical presentation, workup, surgical approach, and pathological findings of the first case report of a patient with adenocarcinoma ex-pleomorphic adenoma of the lacrimal sac and nasolacrimal duct. STUDY DESIGN: Retrospective review of the records of a case of adenocarcinoma ex-pleomorphic adenoma of the lacrimal sac and nasolacrimal duct. METHODS: The clinical presentation, workup, surgical approach, and pathological findings were reviewed. RESULTS: A 51-year-old man presented with a 10-year history of recurrent epiphora of the right eye. At dacryocystorhinostomy a small lesion was visualized within the lumen of the lacrimal sac. A biopsy specimen was consistent with adenocarcinoma. En bloc resection was accomplished using a lateral rhinotomy and medial maxillectomy. The final specimen showed adenocarcinoma ex-pleomorphic adenoma. The patient was given postoperative radiation therapy. He was free of disease 16 months after treatment. CONCLUSIONS: Lacrimal sac tumors should be considered in the differential diagnosis of chronic epiphora. Management of nasolacrimal adenocarcinoma requires complete surgical resection. Radiation treatment in and of itself is not curative but may be useful as adjuvant therapy. Carcinoma ex-pleomorphic adenoma can develop in the lacrimal sac and nasolacrimal duct.  相似文献   
59.
Pleomorphic xanthoastrocytomas (PXAs) are characterized as a well-delineated tumor entity with clear peculiarities in clinico-radiological picture, pathological appearance and biological behavior. Usually the PXAs are associated with relatively good prognosis. Nevertheless, up to 35% of patients die following one and more recurrence with or without tumor malignant transformation. Till now, there is no agreement on what histopathological features constitute to objective and reliable signs of PXAs malignancy and clinical outcome. Thirty-four PXAs were subdivided on three subsets: typical (Grade I) – tumors without mitoses per 20 high power fields, proliferating (Grade II) – tumors with mitoses but without necroses, and malignant (Grade III) – tumors with elevated mitotic index and necrotic foci. Also, immunohistochemical investigation with various tumor-associated antigens was performed. All PXAs subtypes showed differences in clinical outcomes. There were no recurrences and death among the tumors Grade I. Five out of 14 (36%) Grade II PXAs have recurred and one of them died. All 5 patients with PXAs Grade III have rapidly recurred and four of them died. Immunohistochemical variables, such as Ki-S1, p27/Kip1, vascular endothelial growth factor expression, p53 immunoreactivity and apoptotic index also exhibited significant differences among the three PXAs grades. The progression-free survival was significantly reduced for PXAs grade and presence of mitoses, whereas overall survival was reduced for mitotic index 3 and presence of necroses. No one from immunohistochemical variables reached significant value. In summary, the three-tiered PXAs subdivision proposed by us is carrying some element of rationality but, undoubtedly, requires further prospective studies.  相似文献   
60.
Carcinoma ex pleomorphic adenoma poses a challenge to diagnosis and treatment. Herein we describe an extremely unusual case, which presented initially as an intracapsular carcinoma ex pleomorphic adenoma in the right parotid gland. The first recurrence, after an interval of 8 years, showed only recurrence of the benign component. Five years later, a myoepithelial carcinoma arose from the same site. No ductal carcinoma as seen in the initial intracapsular carcinoma ex pleomorphic adenoma was identified. This case report elucidates the atypical clinical behaviour and interesting histological features encountered within this group of salivary neoplasm.  相似文献   
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