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91.
Mantle cell lymphoma and primary nodal marginal zone lymphoma are uncommon tumors thought to arise within discrete anatomic compartments of the B-cell follicle. We report an unusual composite lymphoma comprised of these two neoplasms within an isolated lymph node in a 72-year-old woman. Strikingly, both tumors were completely confined to the respective microanatomic sites of their proposed nonneoplastic lymphoid counterparts, in keeping with early detection of these lesions. The tumors were distinguished by a combination of morphologic, phenotypic, and cytogenetic findings, and the presence of dual, unrelated neoplasms was confirmed by molecular diagnostic studies. After local radiation treatment, there was no recurrence or evidence of systemic disease over more than 2 years. These findings underscore the unique characteristics of these B-cell tumors and support the notion that early in disease development both neoplasms are confined to the distinct anatomic compartments of their postulated normal B-cell counterparts.  相似文献   
92.
We report four consecutive cases of Kommerell's aneurysm of an aberrant left subclavian artery in patients with a right-sided aortic arch and the results of a systematic review of the literature. In our cohort of patients, three had an aneurysm limited to the origin of the aberrant subclavian artery, causing dysphagia and cough, and one had an aneurysm involving also the distal arch and the entire descending thoracic aorta, causing compression of the right main-stem bronchus. A left subclavian-to-carotid transposition was performed in association with the intrathoracic procedure, and a right thoracotomy was used in all patients. One of the patients underwent surgery with deep hypothermia and circulatory arrest, and the others with the adjunct of a left-heart bypass. The repair was accomplished with an interposition graft in two patients and with endoaneurysmorrhaphy in the others. The postoperative course was complicated by respiratory failure and prolonged ventilation in one patient, and one patient died because of severe pulmonary emboli. The survivors are alive and well at a follow-up of 1 to 3 years. Only 32 cases of right-sided aortic arch with an aneurysm of the aberrant subclavian artery have been reported: 12 were associated with aortic dissection, and 2 presented with rupture. Surgical repair was accomplished in 29 patients. A number of operative strategies were described: right thoracotomy, bilateral thoracotomy, left thoracotomy with sternotomy, sternotomy with right thoracotomy, and left thoracotomy. In only 12 cases was the subclavian artery reconstructed. We believe that a right thoracotomy provides good exposure and avoids the morbidity associated with bilateral thoracotomy or sternotomy and thoracotomy. We feel that a left subclavian-to-carotid transposition completed before the thoracic approach revascularizes the subclavian distribution without increasing the complexity of the intrathoracic procedure.  相似文献   
93.
Angiomatoid fibrous histiocytoma (AFH) is an uncommon and mostly indolent soft tissue neoplasm, which usually occurs in the subcutaneous tissue of the extremities in children and young adults. Although the histologic features of AFH are well established, reports of its cytomorphology are very limited. This report characterizes the cytomorphologic features of five cases of AFH, with correlation to clinical, histology, and cytogenetic findings. Smears of fine needle aspiration (FNA; four cases) and intraoperative scrape (one case) were reviewed from five patients with a histologically confirmed diagnosis of AFH. A review of six previously reported AFH cases with cytomorphology was also performed. The tumor presented as a cystic, deep dermal mass in three pediatric cases and as a solid, deeply seated mass in two adults. The cytomorphologic features are mostly nondistinctive and include cellular smears with ovoid to spindled histiocytoid cells that may be isolated or in clusters. Some of these cells are atypical and others contain hemosiderin. Large cellular clusters with a capillary structure and a whorled arrangement of tumor cells can be appreciated in some cases. There is always a bloody background, but a lymphoplasmacytic infiltrate is uncommon. The presences of EWSR1 rearrangement in one case and three copies of FUS gene in another case were detected by fluorescence in situ hybridization. Diagnosing AFH by FNA cytology alone can be challenging because of its rarity and usually nonspecific cytologic findings. Clinical correlation and ancillary studies are essential to reach a specific diagnosis of AFH in small needle biopsies.  相似文献   
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With the advent of the skin sparing mastectomy, immediate breast reconstruction with placement of the definitive prosthesis at the time of mastectomy is possible. The question remains: does single-stage prosthetic reconstruction result in greater numbers of complications or rates of re-operation, compared to two-stage tissue expander reconstruction? A retrospective cohort study of a single centre?s experience with these techniques was carried out. From 2004 to 2012, 54 cases of immediate breast reconstruction with implant were identified, and 108 cases of immediate breast reconstruction using a tissue expander were identified. Gathered preoperative data included tumour, prior exposure to radiation, preoperative chemotherapy, smoking, and comorbidities. Complication rates, as well as the rate of secondary operations, were examined. There were no significant increased risks in the rate of post-operative complications (p?=?.910, odds ratio?=?0.9) nor in the rate of re-operation (p?=?0.421, odds ratio?=?1.4) associated with the insertion of a definitive prosthesis at the time of skin sparing mastectomy. However, previously radiated breasts experienced a 100% rate of wound complications in our subset of 9 breasts that underwent one stage breast reconstruction with immediate final prosthesis placement. Our study suggests that patients with early stage disease can undergo single stage breast reconstruction without increased risk of complications nor need for secondary operations. While the mean time to completion of the reconstructive process is shortened by 5 months with the single stage technique, implant based breast reconstruction requires careful counseling and patient selection in radiated patients.  相似文献   
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We report the first cytogenetic investigation of cranial chordoma. Three cranial chordomas were examined, two of which could be further histopathologically classified as chondroid chordomas. In addition, we have included a case of chordoma of a cervical vertebra to compare the cytogenetic abnormalities. Diagnosis was made at histological and immunohistochemical levels. The three cases of cranial chordoma showed a normal karyotype, while one vertebra showed 46,XY,t(6;11)(q12;q23). Chordomas, particularly those containing cartilage, have to be distinguished from chondrosarcomas of the skull base. Such a distinction is normally based on expression of epithelial markers which usually are lacking in chondrosarcoma. Cytogenetic investigation may eventually prove to be useful in the distinction of the two lesions, if chromosome anomalies are consistently absent in chordoma, although some chondrosarcomas may also present a normal karyotype. Such a distinction has clinical implications because chondroid chordomas show better survival, whereas chondrosarcomas show a propensity to infiltrate the surrounding tissues.  相似文献   
98.
Ohne Zusammenfassung  相似文献   
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