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101.
Background: Prior studies have suggested a number of the subjective visual characteristics that help distinguish between spinal meningiomas and schwannomas on magnetic resonance imaging and computed tomography; however, objective quantification of the signal intensity can be useful information. This study assessed whether quantitative magnetic resonance imaging (MRI) signal intensity (SI) measurements could distinguish intradural-extramedullary schwannomas from meningiomas.Methods: From July 2019 to September 2021, 54 patients with intradural-extramedullary tumors (37 meningiomas and 17 schwannomas) underwent surgery, and tumors were verified pathologically. Defined regions of interest were used to quantify SI values on T1- (T1W) and T2-weighted images (T2W). Receiver operating characteristic curve analysis was used to obtain cutoff values and calculate the area under the curve (AUC), sensitivity (SE), specificity (SP), positive predictive value (PPV), and negative predictive value (NPV).Results: Both Maximum (T2max) and mean (T2mean) T2W SI values demonstrated outstanding (AUC: 0.91) abilities to differentiate meningiomas from schwannomas with Se, Sp, PPV, and NPV values of 94.6%, 70.6%, 87.5%, and 85.7%, respectively, for T2max and 81.1%, 88.2%, 93.8%, and 68.2% for T2mean. The maximum SI value on contrast-enhanced T1W (T1CEmax) and the T2W tumor: fat SI ratio (rTF) demonstrated acceptable abilities (AUC: 0.73 and 0.79, respectively) to differentiate meningiomas from schwannomas with Se, Sp, PPV, and NPV values of 94.6%, 70.6%, 87.5%, and 85.7%, respectively, for T1CEmax and 81.1%, 88.2%, 93.8%, and 68.2% for rTF.Conclusions: Quantitative SI values (T2max, T2mean, T2min, T1CEmax, rTF) can be used to differentiate intradural-extramedullary schwannomas from meningiomas.  相似文献   
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We present a case of histologically confirmed lipomatous meningioma, the first to our knowledge reported in Hong Kong. A 75‐year‐old woman presented to us with on and off dizziness for 1 month. Computed tomography (CT) of the brain showed an extra‐axial mass lesion containing fat and solid enhancing foci at her right frontal region. The definitive diagnosis could be made preoperatively. Postoperative histological examination of the tumour revealed the diagnosis of lipomatous meningioma. We have reviewed the literature and discussed the diagnostic clues, clinical presentation and pathology of this rare tumour.  相似文献   
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Background Appropriate management of cystic lesions of the pancreas is controversial. Major pancreatectomies (pancreaticoduodenectomy or distal pancreatectomy with splenectomy) are the commonly used procedures, even though most cystic lesions are noninvasive neoplasms. We tested the adequacy of limited pancreatectomies in the treatment of pancreatic cystic lesions. Methods Data from 109 patients who underwent surgical resection of a pancreatic cystic lesion at National Taiwan University Hospital from 2001 to 2007 were retrospectively reviewed. Major pancreatomies (n = 79) constituted pancreaticoduodenectomy and total/distal pancreatectomies, while other resection procedures (n = 30) represented limited pancreatectomies. Clinicopathologic features were compared between the major and limited groups. Results There were no statistically significant differences in sex, age, presence of symptoms, cyst diameter, minor or major treatment complications, or pancreatic leakage between the two groups. Cystic lesions located in the neck/body/tail rather than in the head/uncinate process were significantly more often treated with limited pancreatectomy (P = .02). Both groups had similar pathologic distribution of cystic lesions, with the exception of nine invasive neoplasms. The latter were treated with major pancreatectomy. No recurrence was noted in 100 patients with noninvasive cystic neoplasms after major or limited pancreatectomy. Conclusions Noninvasive pancreatic cystic neoplasms can be safely and effectively treated by limited pancreatectomy.  相似文献   
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Breast cancer is one of the most common cancers in women worldwide and metastasis is the major cause of breast cancer death. Development of new therapeutic agents for inhibiting breast cancer metastasis is therefore an urgent need. We previously demonstrated that recombinant DNA-derived viral capsid protein VP1 (rVP1) of foot-and-mouth disease virus-induced apoptosis of MCF-7 breast cancer cells in vitro. Here, we investigated whether rVP1 exhibits any inhibitory effects on migration/metastasis and human epidermal growth factor receptor 2 (HER-2), a well-known biomarker for poor prognosis of breast cancer. The effects of rVP1 on cancer cell migration/invasion and metastasis were evaluated using Transwell migration assay and animal cancer models of metastasis. Western blotting, RT-PCR, flow cytometry, immunohistochemistry, and immunofluorescence staining techniques were used to investigate the effects of rVP1 on HER-2 and signal transduction mediators. Non-cytotoxic concentrations of rVP1-induced mesenchymal-epithelial transition and significantly suppressed AP-2?? and HER-2 expression as well as the migration and invasion of a variety of breast cancer cell lines in a ??1-integrin-dependent manner in vitro. Gross and histopathologic examinations showed that rVP1 also suppressed metastasis of several breast cancer cell lines, including HER-2-overexpressing SK-BR-3 and BT-474 cells to lung, liver, or peripheral lymph node in orthotopic allograft/xenograft murine models. In addition, rVP1 significantly prolonged survival in breast cancer-bearing mice. Notably, no apparent side effects of rVP1 were detected, as shown by normal complete blood count levels and serum biochemistry profiles, including AST, ALT, BUN, and creatine. This study demonstrates that rVP1 suppresses the migration, invasion, and metastasis of breast cancer cells via binding to ??1 integrin receptor and down-regulation of AP-2?? and HER-2 expression. The effectiveness of rVP1 on inhibiting migration/metastasis of breast cancer and HER-2 expression suggests that it may be suitable for serving as potential therapeutics for metastatic breast cancer particularly HER-2-overexpressing cancer.  相似文献   
106.
Asian American women's historically low breast cancer mortality rate has remained constant as rates decreased for all other races. From 2000 to 2004, a randomized controlled trial explored the Asian grocery store-based breast cancer education program's impact on Chinese, Filipino, Korean, and Vietnamese women (n?=?1,540). Women aged 40 and older and non-adherent for annual screening mammograms were more likely to schedule a mammogram after receiving the breast cancer education program than women randomized to the prostate cancer program (X 2?=?3.85, p?=?0.05). With the right program ingredients, late adopters of breast cancer screening can be prompted to change.  相似文献   
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Tooth extraction inevitably accompanies alveolar ridge resorption with loss of pre-existing tissue morphology. Replacing missing teeth with dental implants has become popular, but restoring anterior teeth with implant-supported restorations is a technique-sensitive task and poses challenges for dentists. With the progress of implant dentistry, the demand for optimal esthetics has become linked with the desire for faster, easier techniques that shorten treatment time and also satisfy patients. Immediate provisionalization of a single-tooth implant provides significant benefits compared with traditional delayed protocols, such as aiding the contouring of peri-implant soft tissue and enhancing patient comfort and satisfaction. This article describes a meticulous approach to a hopeless maxillary central incisor with root fracture. The defect in the extraction socket was reconstructed using autogenous bone harvested from the chin. Four months later, an implant was installed and immediately restored. After another healing period of 6 months, the peri-implant soft tissue had been shaped and matured according to the contours of the provisional restoration. The emergence profile was used to duplicate the definitive restoration. Peri-implant esthetics was achieved through socket augmentation and immediate provisionalization of the implant. This treatment modality attained predictable and maintainable outcomes, both functionally and esthetically.  相似文献   
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