全文获取类型
收费全文 | 92946篇 |
免费 | 9425篇 |
国内免费 | 4648篇 |
专业分类
耳鼻咽喉 | 2596篇 |
儿科学 | 363篇 |
妇产科学 | 1706篇 |
基础医学 | 10358篇 |
口腔科学 | 3400篇 |
临床医学 | 6646篇 |
内科学 | 11547篇 |
皮肤病学 | 1974篇 |
神经病学 | 218篇 |
特种医学 | 4282篇 |
外国民族医学 | 122篇 |
外科学 | 13634篇 |
综合类 | 16519篇 |
现状与发展 | 23篇 |
预防医学 | 2016篇 |
眼科学 | 395篇 |
药学 | 4612篇 |
14篇 | |
中国医学 | 1131篇 |
肿瘤学 | 25463篇 |
出版年
2024年 | 50篇 |
2023年 | 1277篇 |
2022年 | 1973篇 |
2021年 | 3375篇 |
2020年 | 3152篇 |
2019年 | 2997篇 |
2018年 | 2865篇 |
2017年 | 3275篇 |
2016年 | 3701篇 |
2015年 | 4227篇 |
2014年 | 6217篇 |
2013年 | 5459篇 |
2012年 | 5652篇 |
2011年 | 6124篇 |
2010年 | 4988篇 |
2009年 | 4925篇 |
2008年 | 5119篇 |
2007年 | 5427篇 |
2006年 | 5071篇 |
2005年 | 4529篇 |
2004年 | 3577篇 |
2003年 | 3138篇 |
2002年 | 2680篇 |
2001年 | 2580篇 |
2000年 | 2185篇 |
1999年 | 1694篇 |
1998年 | 1447篇 |
1997年 | 1248篇 |
1996年 | 1134篇 |
1995年 | 1068篇 |
1994年 | 978篇 |
1993年 | 678篇 |
1992年 | 594篇 |
1991年 | 517篇 |
1990年 | 437篇 |
1989年 | 380篇 |
1988年 | 363篇 |
1987年 | 291篇 |
1986年 | 240篇 |
1985年 | 260篇 |
1984年 | 212篇 |
1983年 | 151篇 |
1982年 | 172篇 |
1981年 | 147篇 |
1980年 | 136篇 |
1979年 | 109篇 |
1978年 | 76篇 |
1977年 | 53篇 |
1976年 | 45篇 |
1975年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
《Journal of vascular and interventional radiology : JVIR》2022,33(9):1045-1053
PurposeTo evaluate the efficacy and safety of microwave (MW) ablation as first-line locoregional therapy (LRT) for bridging patients with hepatocellular carcinoma (HCC) to liver transplant.Materials and MethodsThis retrospective study evaluated 88 patients who received percutaneous MW ablation for 141 tumors as first-line LRT for HCC and who were listed for liver transplantation at a single medical center between 2011 and 2019. The overall survival (OS) rate statuses after liver transplant, waitlist retention, and disease progression were evaluated using the Kaplan-Meier techniques.ResultsAmong the 88 patients (72 men and 16 women; mean age, 60 years; Model for End-Stage Liver Disease score, 11.2) who were listed for transplant, the median waitlist time was 9.4 months (interquartile range, 5.5–18.9). Seventy-one (80.7%) patients received transplant after a median waitlist time of 8.5 months. Seventeen (19.3%) patients were removed from the waitlist; of these, 4 (4.5%) were removed because of tumors outside of the Milan criteria (HCC-specific dropout). No difference in tumor size or alpha-fetoprotein was observed in the transplanted versus nontransplanted patients at the time of ablation (2.1 vs 2.1 cm and 34.4 vs 34.7 ng/mL for transplanted vs nontransplanted, respectively; P > .05). Five (5.1%) of the 88 patients experienced adverse events after ablation; however, they all recovered. There were no cases of tract seeding. The local tumor progression (LTP) rate was 7.2%. The OS status after liver transplant at 5 years was 76.7%, and the disease-specific survival after LTP was 89.6%, with a median follow-up of 61 months for all patients.ConclusionsMW ablation appears to be safe and effective for bridging patients with HCC to liver transplant without waitlist removal from seeding, adverse events, or LTP. 相似文献
32.
目的探究槐耳颗粒对肝癌根治术后复发转移的影响。方法114例行肝癌根治术患者,按治疗方法不同分为对照组(54例)和观察组(60例)。对照组行常规治疗,观察组行常规+槐耳颗粒治疗。对比两组生存及肿瘤复发转移情况、血管内皮细胞生长因子(VEGF)、血清甲胎蛋白(AFP)、总胆红素(TB)、丙氨酸转氨酶(ALT)、生活质量改善情况。结果观察组存活率90.00%高于对照组的75.93%,复发转移率8.33%低于对照组的25.93%,差异有统计学意义(P<0.05)。治疗后,观察组VEGF(413.54±21.05)pg/ml、AFP(356.32±25.36)μg/L均低于对照组的(486.53±20.43)pg/ml、(415.69±21.32)μg/L,差异有统计学意义(P<0.05)。治疗后,观察组TB(18.63±1.34)μmol/L、ALT(52.78±5.32)U/L低于对照组的(21.66±1.25)μmol/L、(56.23±5.63)U/L,差异有统计学意义(P<0.05)。观察组患者生活质量改善情况优于对照组,差异有统计学意义(P<0.05)。结论槐耳颗粒在防治肝癌术后肿瘤复发转移方面具有明显效果,推荐使用。 相似文献
33.
目的:探索携带CTLA-4 siRNA的适配子偶联脂质体颗粒是否可以激活肿瘤部位的抗肿瘤免疫反应,抑制肾细胞癌的生长。方法:采用薄膜水化法制备脂质体;使用透射电子显微镜观察脂质体的形态和结构;用Zetasizer测量Zeta电位;共孵育实验观察靶细胞对Lipo-siRNA的摄取;qPCR检测Lipo-siRNA对CTLA-4基因的沉默;小鼠移植瘤模型检测Lipo-siRNA的体内抑瘤能力;流式细胞术检测肿瘤浸润T细胞的激活状态;免疫荧光法检测肿瘤浸润T细胞的数目。结果:成功制备Lipo-siRNA,电镜结果显示其具有双层球状结构;Zetasizer测得其Zeta电位为(+20.53±2.66)mV;荧光显微镜观察结果表明Lipo-siRNA可以被靶细胞有效摄取,qPCR检测Lipo-siRNA可以显著降低CTLA-4基因的表达(P<0.001);小鼠移植瘤模型显示Lipo-siRNA较对照组而言可以显著抑制肿瘤生长(P<0.001),降低肿瘤细胞中CTLA-4的表达(P<0.001),提升肿瘤浸润T细胞的数量(P<0.000 1),并且提高了肿瘤浸润T细胞中IL-2(P<0.000 1)和IFN-γ(P<0.000 1)的表达水平。结论:适配子偶联脂质体可以携带CTLA-4 siRNA靶向肿瘤细胞,激活肿瘤部位的抗肿瘤免疫反应,抑制肿瘤的生长,对肾细胞癌的治疗具有潜在的临床应用价值。 相似文献
34.
35.
《Radiography》2022,28(3):718-724
IntroductionLiver cancer lesions on Computed Tomography (CT) withholds a great amount of data, which is not visible to the radiologists and radiographer. Radiomics features can be extracted from the lesions and used to train Machine Learning (ML) algorithms to predict between tumour and liver tissue. The purpose of this study was to investigate and classify Radiomics features extracted from liver tumours and normal liver tissue in a limited CT dataset.MethodsThe Liver Tumour Segmentation Benchmark (LiTS) dataset consisting of 131 CT scans of the liver with segmentations of tumour tissue and healthy liver was used to extract Radiomic features. Extracted Radiomic features included size, shape, and location extracted with morphological and statistical techniques according to the International Symposium on Biomedical Imaging manual. Relevant features was selected with chi2 correlation and principal component analysis (PCA) with tumour and healthy liver tissue as outcome according to a consensus between three experienced radiologists. Logistic regression, random forest and support vector machine was used to train and validate the dataset with a 10-fold cross-validation method and the Grid Search as hyper-parameter tuning. Performance was evaluated with sensitivity, specificity and accuracy.ResultsThe performance of the ML algorithms achieved sensitivities, specificities and accuracy ranging from 96.30% (95% CI: 81.03%–99.91%) to 100.00% (95% CI: 86.77%–100.00%), 91.30% (95% CI: 71.96%–98.93%) to 100.00% (95% CI: 83.89%–100.00%)and 94.00% (95% CI: 83.45%–98.75%) to 100.00% (95% CI: 92.45%–100.00%), respectively.ConclusionML algorithms classifies Radiomics features extracted from healthy liver and tumour tissue with perfect accuracy. The Radiomics signature allows for a prognostic biomarker for hepatic tumour screening on liver CT.Implications for practiceDifferentiation between tumour and liver tissue with Radiomics ML algorithms have the potential to increase the diagnostic accuracy, assist in the decision-making of supplementary multiphasic enhanced medical imaging, as well as for developing novel prognostic biomarkers for liver cancer patients. 相似文献
36.
Xiao-Long Tang Yan-Dong Miao Deng-Hai Mi 《World journal of gastrointestinal oncology》2022,14(1):366-368
The present letter to the editor is in response to the research “Outcomes of curative liver resection for hepatocellular carcinoma in patients with cirrhosis” by Elshaarawy et al in World J Gastroenterol 2021; 13(5): 424–439. The preoperative assessment of the liver reserve function in hepatocellular carcinoma (HCC) patients with cirrhosis is crucial, and there is no universal consensus on how to assess it. Based on a retrospective study, Elshaarawy et al investigated the impact of various classical clinical indicators on liver failure and the prognosis after hepatectomy in HCC patients with cirrhosis. We recommend that we should strive to explore new appraisal indicators, such as the indocyanine green retention rate at 15 min. 相似文献
37.
BackgroundTo investigate perioperative complication rates at radical nephrectomy (RN) according to inferior vena cava thrombectomy (IVC-T) status and stage (metastatic vs non-metastatic) within kidney cancer patients.Materials and methodsWe ascertained perioperative complication rates within the National Inpatient Sample database (2016–2019). First, log-link linear Generalized Estimating Equation function (GEE) regression models (adjusted for hospital clustering and weighted for discharge disposition) tested complication rates in IVC-T patients, according to metastatic stage. Subsequently, a subgroup analysis relied on RN patients with or without IVC-T. Here, multivariable logistic regression models tested complication rates in RN patients according to IVC-T status, after propensity score matching including metastatic stage.ResultsOf 26,299 RN patients, 461 (2%) patients underwent IVC-T. Of those, 252 (55%) were non-metastatic vs 209 (45%) were metastatic. Rates of acute kidney injury (AKI), transfusion, cardiac, thromboembolic and other medical complications in non-metastatic vs metastatic patients were 40 vs 40%, 25 vs 22%, 21 vs 23%, 19 vs 14% and 38 vs 40%, respectively (all p ≥ 0.2). Metastatic stage in IVC-T patients did not predict differences in complications in log-link linear GEE regression models (all p > 0.1). However, in logistic regression models with propensity score matching, relying on the overall cohort of RN patients, IVC-T status was associated with higher complication rates (all p < 0.001): AKI (Odds ratio [OR]:2.60; 95%-CI [95%-Confidence interval: 1.97–3.44), transfusions (OR:2.40; 95%-CI: 1.72–3.36), cardiac (OR:2.27; 95%-CI: 1.49–3.47), thromboembolic (OR:9.07; 95%-CI: 5.21–16.58) and other medical complications (OR:2.01; 95%-CI: 1.52–2.66).ConclusionsThe current analyses indicate that presence of concomitant IVC-T is associated with higher complication rate at RN. Conversely, metastatic stage has no effect on recorded complication rates. 相似文献
38.
《Diagnostic Histopathology》2022,28(3):142-148
Adenoid cystic carcinoma (AdCC) is a salivary gland-type of cancer that may also occur in the breast. Breast AdCC shows the same morphological spectrum as is observed in salivary glands, with recognition of individual subtypes that may differ in their clinical behaviour. AdCC classic variant (C-AdCC) is a slowly growing tumour, with a low rate of axillary node and distant metastases. Local recurrences may develop as a consequence of incomplete surgical excision. C-AdCC should be differentiated from the solid-basaloid variant of AdCC (SB-AdCC) that is characterized by nuclear atypia, frequent mitotic figures and necrosis, in addition to the solid architecture. SB-AdCC is a more aggressive tumour, with higher rates of axillary node and distant metastases. AdCC may also co-exist with more aggressive types of carcinoma including metaplastic and neuroendocrine carcinoma, referred to as AdCC with high grade transformation (HG-AdCC). This paper reviews the key diagnostic criteria of the different subtypes of breast AdCC with emphasis on differential diagnosis and prognostic parameters. 相似文献
39.
《The British journal of oral & maxillofacial surgery》2022,60(7):890-895
Patients undergoing sentinel node biopsy (SLNB) for early oral squamous cell carcinoma (OSCC) who harbour occult metastases (pN+ve) may be at greater risk of mortality due to prolonged overall treatment times than those identified as pN+ve on elective neck dissection (ELND). A retrospective comparative survival analysis was therefore undertaken to test this hypothesis. Patients were identified from the South Glasgow multidisciplinary team (MDT) database. Group 1 comprised 38 patients identified as pN+ve, or who were false negative, on sentinel lymph node biopsy (SLNB). Group 2 comprised 146 patients staged pN+ve on ELND. The groups were compared with the Kaplan Meier method and Cox proportional hazards model. In addition, a matched-pair analysis was performed. A unique and specifically designed algorithm was deployed to optimise the pairings. No difference in disease-specific or overall survival was found between the groups. Patients undergoing SLNB as the initial neck staging modality in early OSCC and are identified as pN+ve do not appear to be at a survival disadvantage compared with those staged with ELND. 相似文献
40.
Syed M. Gilani Muhammad Khan Andrea Barbieri Manju L. Prasad 《Diagnostic Histopathology》2021,27(6):263-271
Anaplastic thyroid carcinoma (ATC) is an aggressive thyroid malignancy with high mortality rate. This malignancy arises in thyroid follicular cells either denovo or with an associated differentiated thyroid carcinoma component. Clinically, it usually presents as a rapidly enlarging mass, pain and locally compressive symptoms. Histopathologic variability and heterogeneity often pose diagnostic challenges, especially in scant and paucicellular specimens. This article describes the clinical, histopathologic and molecular features of ATC and also addresses the associated diagnostic limitations and challenges. 相似文献