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Angiography is often performed to identify the vascular supply of hemangioblastomas prior to resection. Conventional two-dimensional (2D) digital subtraction (DS) angiography and three-dimensional (3D) DS angiography provides high-resolution images of the vascular structures associated with these lesions. However, such 3D DS angiography often does not provide reliable anatomical information about nearby osseous structures, or when it does, resolution of vascular anatomy in the immediate vicinity of bone is sacrificed. A novel angiographic reconstruction algorithm was recently developed at The Johns Hopkins University to overcome these inadequacies. By combining two separate sequences of images of bone and blood vessels in a single 3D representation, 3D fusion DS (FDS) angiography provides precise topographic information about vascular lesions in relation to the osseous environment, without a loss of resolution. In this paper, the authors present the cases of two patients with cervical spine hemangioblastomas who underwent preoperative evaluation with FDS angiography and then successful gross-total resection of their tumors. In both cases, FDS angiography provided high-resolution 3D images of the hemangioblastoma anatomy, including each tumor's topographic relationship with adjacent osseous structures and the location and size of feeding arteries and draining veins. These cases provide evidence that FDS angiography represents a useful adjunct to magnetic resonance imaging and 2D DS angiography in the preoperative evaluation and surgical planning of patients with vascular lesions in an osseous environment, such as hemangioblastomas in the spinal cord.  相似文献   
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BACKGROUND: The cytopathologic distinction between hepatocellular carcinoma (HCC) and metastatic carcinoma (MC) in the liver can be problematic, especially in patients with poorly differentiated HCC, in whom a trabecular pattern, bile production, and Mallory bodies may not be apparent on small fine-needle aspiration (FNA) samples. HepPar1 (OCH1E5) is a monoclonal antibody specifically developed to react with hepatocytes. It rarely reacts with bile duct and nonparenchymal liver cells. METHODS: FNA samples (cell blocks) from 75 liver tumors were selected. These included 50 moderate to poorly differentiated HCC cases, 5 cholangiocarcinoma (CC) cases, and 20 MC cases (4 from the breast, 4 from the stomach, 4 from the pancreas, and 8 from the colon). Immunohistochemical staining for HepPar1 was performed to differentiate HCC from MC. RESULTS: The HepPar1 antibody was positive in 50 of 50 HCC cases (100%). The positivity was cytoplasmic, diffuse, and granular. All 5 cases of CC were found to be negative (0%). Although focal positivity within tumor cells was noted in one case, cytologically these were entrapped normal hepatocytes between the tumor cells. In addition, 3 of 20 MC cases (15%) also were positive for HepPar1. All three cases originated from gastric primary tumors and exhibited diffuse, granular cytoplasmic staining. CONCLUSIONS: The results of the current study demonstrate that HepPar1 is an effective marker with which to differentiate between HCC and CC and/or MC. HepPar1 was found to demonstrate 100% positivity in HCC cases, compared with 0% and 15% positivity, respectively, in CC and MC cases. In addition, HepPar1 is extremely helpful in limited tissue samples from FNA. Although 15% of the MC cases in the current study were found to be positive, with the help of clinical correlation and other immunohistochemical stains a definite diagnosis could be rendered. Potential pitfalls include residual benign hepatocyte staining within a non-HCC malignancy, as was observed in one of the CC cases in the current study.  相似文献   
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OBJECT: The extent of tumor resection that should be undertaken in patients with glioblastoma multiforme (GBM) remains controversial. The purpose of this study was to identify significant independent predictors of survival in these patients and to determine whether the extent of resection was associated with increased survival time. METHODS: The authors retrospectively analyzed 416 consecutive patients with histologically proven GBM who underwent tumor resection at the authors' institution between June 1993 and June 1999. Volumetric data and other tumor characteristics identified on magnetic resonance (MR) imaging were collected prospectively. CONCLUSIONS: Five independent predictors of survival were identified: age, Karnofsky Performance Scale (KPS) score, extent of resection, and the degree of necrosis and enhancement on preoperative MR imaging studies. A significant survival advantage was associated with resection of 98% or more of the tumor volume (median survival 13 months, 95% confidence interval [CI] 11.4-14.6 months), compared with 8.8 months (95% CI 7.4-10.2 months; p < 0.0001) for resections of less than 98%. Using an outcome scale ranging from 0 to 5 based on age, KPS score, and tumor necrosis on MR imaging, we observed significantly longer survival in patients with lower scores (1-3) who underwent aggressive resections, and a trend toward slightly longer survival was found in patients with higher scores (4-5). Gross-total tumor resection is associated with longer survival in patients with GBM, especially when other predictive variables are favorable.  相似文献   
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Background context

Intramedullary ependymomas constitute the most frequent type of intramedullary tumor. In patients with neurofibromatosis type 2 (NF2), multiple intramedullary ependymomas are known to occur. In the non-NF2 population, however, the presence of multiple synchronous intramedullary ependymomas is exceedingly rare.

Purpose

In this article, the authors report the second case in the literature of multiple primary synchronous intramedullary ependymomas. To the best of the authors knowledge, this report represents the first to provide a detailed pathology of all lesions, thereby giving an added level of confidence on the primary synchronous nature of the lesions. The authors have also performed a review of the literature regarding multifocal intramedullary ependymomas.

Study design

A review article and case report.

Conclusions

The concomitant localization of two primary intramedullary spinal cord ependymomas in the setting of nongenetic predisposition is an uncommon phenomenon. In this article, the authors present the second report of multiple, synchronous intramedullary ependymomas. A detailed review of the literature reveals that the presence of multiple intramedullary lesions in non-NF2 patients is both rare and deserving of further study.  相似文献   
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The histology of the primary tumor in metastatic spine disease plays an important role in its treatment and prognosis. However, there is paucity in the literature of histology-specific analysis of spinal metastases. In this study, prognostic variables were reviewed for patients who underwent surgery for breast metastases to the spinal column. Respective chart review was done to first identify all patients with breast cancer over an 8-year period at a major cancer center and then to select all those with symptomatic metastatic disease to the spine who underwent spinal surgery. Univariate and multivariate analyses were used to assess several prognostic variables. Presence of visceral metastases, multiplicity of bony lesions, presence of estrogen receptors (ER), and segment of spine (cervical, thoracic, lumbar, sacral) in which metastases arose were compared with patient survival. Eighty-seven patients underwent 125 spinal surgeries. Those with estrogen receptor (ER) positivity had a longer median survival after surgery compared to those with estrogen receptor negativity. Patients with cervical location of metastasis had a shorter median survival compared with those having metastases in other areas of the spine. The presence of visceral metastases or a multiplicity of bony lesions did not have prognostic value. In patients with spinal metastases from breast cancer, aggressive surgical management may be an option for providing significant pain relief and preservation/improvement of neurological function. Interestingly, in patients undergoing such surgery, cervical location of metastasis is a negative prognostic variable, and ER-positivity is associated with better survival, while presence of visceral or multiple bony lesions does not significantly alter survival.  相似文献   
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