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《Pancreatology》2014,14(2):117-124
PurposeIntraductal pancreatic mucinous neoplasms (IPMN) are precancerous cystic lesions. The aim was to investigate the in situ IPMN proteome using MALDI (Matrix-Assisted Laser Desorption/Ionisation) imaging and to characterize biomarkers associated with the grade of dysplasia.Experimental designFrozen human Branch duct -IPMN sections were selected according to dysplasia and proteomic analyses were performed by MALDI imaging to obtain mass spectra distribution. The most discriminating peaks were identified using tissue extraction and nanoLC-ESI-MS/MS. Identified peaks were validated in independent series of IPMN by immunochemistry on surgical specimens (tissue-microarrays (TMA), n = 45) and endoscopic ultrasound fine-needle aspiration (EUS FNA) samples (n = 25).ResultsBD-IPMN samples with low (n = 10) and high (n = 10) grades of dysplasia were analyzed. Differential spectra of proteins were found in the two groups with significantly different intensities (n = 15). The two peaks (intense in high grade IPMN) (m/z 8565 and 4747) were characterized as the monomeric ubiquitin (Mascot score = 319.22) and an acetylated fragment of thymosin-β4 (2–42) (Omssa score = 1.37 E−9). Validation on TMA and EUS FNA samples confirmed that ubiquitin was overexpressed in high grade dysplasia (p = 0.04 and p = 0.0004). Thymosin-β4 expression was confirmed on TMA by immunohistochemistry on high grade IPMN (p = 0.011).ConclusionUbiquitin and thymosin-β4 are overexpressed in IPMN with high grade dysplasia. Positive immunochemical staining on EUS-FNA material is a major argument in support of preventive resection.  相似文献   
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Esophageal squamous cell carcinoma(ESCC) is a common malignant tumor of the digestive system worldwide, especially in China. Due to the lack of effective early detection methods, ESCC patients often present at an advanced stage at the time of diagnosis, which seriously affects the prognosis of patients. At present,early detection of ESCC mainly depends on invasive and expensive endoscopy and histopathological biopsy. Therefore, there is an unmet need for a noninvasive method to detect ESCC in the early stages. With the emergence of a large class of non-invasive diagnostic tools, serum tumor markers have attracted much attention because of their potential for detection of early tumors. Therefore, the identification of serum tumor markers for early detection of ESCC is undoubtedly one of the most effective ways to achieve early diagnosis and treatment of ESCC.This article reviews the recent advances in the discovery of blood-based ESCC biomarkers, and discusses the origins, clinical applications, and technical challenges of clinical validation of various types of biomarkers.  相似文献   
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BACKGROUND Autotaxin(ATX) has been reported as a direct biomarker for estimating the evaluation of liver fibrosis. But available data on ATX as a useful biomarker for the complications of liver cirrhosis(LC) are scant.AIM To assess the clinical usefulness of ATX for assessing the complications of LC.METHODS This multicenter, retrospective study was conducted at six locations in Japan. We include patients with LC, n = 400. The ATX level was evaluated separately in men and women because of its high level in female patients. To assess the clinical usefulness of ATX for the complications of LC, the area under the curve(AUC) of ATX assessing for the severe complications was analyzed in comparison with the model for end-stage liver disease score, albumin-bilirubin(ALBI) score, fibrosis-4 index, and aspartate aminotransferase-to-platelet ratio index.RESULTS The mean age was 68.4 ± 11.4 years, 240 patients(60.0%) were male. A total of 213(53.3%) and 187(46.8%) patients were compensated and decompensated,respectively. The numbers of patients with varix rupture, hepatic ascites, and hepatic encephalopathy were 35(8.8%), 131(32.8%), and 103(25.8%),respectively. The AUCs of ATX in men for hepatic encephalopathy, hepatic ascites, and varix ruptures were 0.853, 0.816, and 0.706, respectively. The AUCs of ATX in women for hepatic encephalopathy, hepatic ascites, and varix rupture were 0.759, 0.717, and 0.697, respectively. The AUCs of ATX in men were higher than those in women, as were all the other biomarkers used to detect encephalopathy and varix ruptures. However, for detecting ascites, the AUC of ALBI in men was more effective than using ATX.CONCLUSION ATX in men was more effective than any other biomarkers for detecting hepatic encephalopathy and varix ruptures.  相似文献   
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At present chronic liver disease(CLD),the third commonest cause of premature death in the United Kingdom is detected late,when interventions are ineffective,resulting in considerable morbidity and mortality.Injury to the liver,the largest solid organ in the body,leads to a cascade of inflammatory events.Chronic inflammation leads to the activation of hepatic stellate cells that undergo transdifferentiation to become myofibroblasts,the main extra-cellular matrix producing cells in the liver;over time increased extra-cellular matrix production results in the formation of liver fibrosis.Although fibrogenesis may be viewed as having evolved as a“wound healing”process that preserves tissue integrity,sustained chronic fibrosis can become pathogenic culminating in CLD,cirrhosis and its associated complications.As the reference standard for detecting liver fibrosis,liver biopsy,is invasive and has an associated morbidity,the diagnostic assessment of CLD by non-invasive testing is attractive.Accordingly,in this review the mechanisms by which liver inflammation and fibrosis develop in chronic liver diseases are explored to identify appropriate and meaningful diagnostic targets for clinical practice.Due to differing disease prevalence and treatment efficacy,disease specific diagnostic targets are required to optimally manage individual CLDs such as non-alcoholic fatty liver disease and chronic hepatitis C infection.To facilitate this,a review of the pathogenesis of both conditions is also conducted.Finally,the evidence for hepatic fibrosis regression and the mechanisms by which this occurs are discussed,including the current use of antifibrotic therapy.  相似文献   
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Gastric cancer is the fourth most common cancer in the world and the second leading cause of cancerrelated death.More than 80%of diagnoses occur at the middle to late stage of the disease,highlighting an urgent need for novel biomarkers detectable at earlier stages.Recently,aberrantly expressed microRNAs(miRNAs)have received a great deal of attention as potential sensitive and accurate biomarkers for cancer diagnosis and prognosis.This review summarizes the current knowledge about potential miRNA biomarkers for gastric cancer that have been reported in the publicly available literature between 2008 and 2013.Available evidence indicates that aberrantly expressed miRNAs in gastric cancer correlate with tumorigenesis,tumor proliferation,distant metastasis and invasion.Furthermore,tissue and cancer types can be classified using miRNA expression profiles and next-generation sequencing.As miRNAs in plasma/serum are well protected from RNases,they remain stable under harsh conditions.Thus,potential functions of these circulating miRNAs can be deduced and may implicate their diagnostic value in cancer detection.Circulating miRNAs,as well as tissue miRNAs,may allow for the detection of gastric cancer at an early stage,prediction of prognosis,and monitoring of recurrence and/or lymph node metastasis.Taken together,the data suggest that the participation of miRNAs in biomarker development will enhance the sensitivity and specificity of diagnostic and prognostic tests for gastric cancer.  相似文献   
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子宫内膜异位症的发病机制不明,缺乏有效的生物标志物,疾病的延误诊断非常突出。脂质组学技术为子宫内膜异位症的诊断和预测提供了新的途径。外周血、子宫内膜液、腹腔液和卵泡液的鞘磷脂、磷脂酰胆碱和磷脂酰丝氨酸等对子宫内膜异位症及疾病分型具有良好的诊断价值;在位子宫内膜的磷脂酰胆碱、磷脂酰丝氨酸联合磷脂酸有望成为早期子宫内膜异位症的生物标志物;外周血的脂代谢数据对预测子宫内膜异位症相关不孕也有重要价值。脂质组学技术的发展将进一步推进子宫内膜异位症相关发病机制、疾病预测、诊断和治疗等方面的研究进展。  相似文献   
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