首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   94759篇
  免费   9427篇
  国内免费   4732篇
耳鼻咽喉   2278篇
儿科学   391篇
妇产科学   1717篇
基础医学   11080篇
口腔科学   4265篇
临床医学   6828篇
内科学   11943篇
皮肤病学   1989篇
神经病学   254篇
特种医学   4239篇
外国民族医学   123篇
外科学   14023篇
综合类   16413篇
现状与发展   23篇
预防医学   1996篇
眼科学   403篇
药学   4620篇
  14篇
中国医学   1150篇
肿瘤学   25169篇
  2024年   174篇
  2023年   1395篇
  2022年   2804篇
  2021年   3679篇
  2020年   3233篇
  2019年   3046篇
  2018年   2912篇
  2017年   3275篇
  2016年   3703篇
  2015年   4268篇
  2014年   6212篇
  2013年   5499篇
  2012年   5632篇
  2011年   6098篇
  2010年   4935篇
  2009年   4886篇
  2008年   5077篇
  2007年   5323篇
  2006年   4974篇
  2005年   4444篇
  2004年   3534篇
  2003年   3117篇
  2002年   2677篇
  2001年   2544篇
  2000年   2158篇
  1999年   1749篇
  1998年   1598篇
  1997年   1452篇
  1996年   1278篇
  1995年   1083篇
  1994年   1001篇
  1993年   709篇
  1992年   622篇
  1991年   552篇
  1990年   462篇
  1989年   401篇
  1988年   372篇
  1987年   304篇
  1986年   246篇
  1985年   264篇
  1984年   225篇
  1983年   157篇
  1982年   185篇
  1981年   155篇
  1980年   149篇
  1979年   122篇
  1978年   84篇
  1977年   57篇
  1976年   54篇
  1975年   17篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Carcinosarcomas are biphasic tumors composed of admixed malignant epithelial and mesenchymal components. Numerous terms have been used to name such neoplasms; therefore, terminological confusion is frequent. Most examples of carcinosarcomas are encountered in non‐cutaneous sites, with approximately 100 cases of cutaneous carcinosarcomas reported so far in the English literature. Although different theories have been suggested to explain the occurrence of these peculiar neoplasms, histogenetic mechanisms should be better hypothesized depending on each individual case. Even though prognosis tends to be related to the specific components of the lesion, especially the epithelial one, it seems that cases of cutaneous localization usually have a better outcome. We report an exceedingly rare case of syringocystadenocarcinoma papilliferum which showed an atypical stroma with sarcomatoid appearance, and highlight that the terminology used for this spectrum of lesions is disorganized and confusing.  相似文献   
82.
83.
BackgroundWe sought to identify treatment disparities existing prior to publication of the 2015 American Thyroid Association Management Guidelines in order to identify patients with papillary thyroid cancer (PTC) at risk for receiving inadequate treatment.MethodsPatients diagnosed with PTC from 2011 to 2013 were identified using Surveillance, Epidemiology and End Results database. High-risk disease was defined as T4, N1, or M1. Chi-square tests compared characteristics of patients with and without high-risk disease and characteristics of high-risk patients who did and did not receive radioactive iodine ablation (RAI). Likelihoods of having high-risk disease, of receiving RAI, and of cause-specific death were calculated using regression analyses.ResultsSample included 32,229 individuals; 7894 (24.5%) had high-risk disease. Mean age was 50.0 years, 24,815 (77.0%) were female, and 21,318 (66.2%) were white. Odds of high-risk disease were greater among males (OR:2.04; 95% CI:1.92–2.16), Hispanics (OR:1.67; 95% CI:1.56–1.79) and Asians (OR:1.49; 95% CI:1.37–1.62), and uninsured (OR:1.24; 95% CI:1.07–1.43), and lower among patients ages 45–64 (OR:0.57; 95% CI:0.53–0.60), and ≥65 years (OR:0.54; 95% CI:0.50–0.59), and Blacks (OR:0.46; 95% CI:0.40–0.53). Most (69.3%) high-risk patients received RAI. Odds of receiving RAI were lower among patients age ≥65 years (OR:0.67; 95% CI:0.58–0.77), uninsured (OR:0.52; 95% CI:0.41–0.67), or with Medicaid (OR:0.58; 95% CI:0.50–0.69). RAI use reduced the risk of cause-specific mortality (HR:0.29; 95% CI:0.18–0.47).ConclusionKnowledge of these treatment disparities will allow recognition of groups at risk for high-risk disease and receiving inadequate treatment.  相似文献   
84.
85.
86.
Background and aimPatient decision aids for oncological treatment options, provide information on the effect on recurrence rates and/or survival benefit, and on side-effects and/or burden of different treatment options. However, often uncertainty exists around the probability estimates for recurrence/survival and side-effects which is too relevant to be ignored. Evidence is lacking on the best way to communicate these uncertainties. The aim of this study is to develop a method to incorporate uncertainties in a patient decision aid for breast cancer patients to support their decision on radiotherapy.MethodsFirstly, qualitative interviews were held with patients and health care professionals. Secondly, in the development phase, thinking aloud sessions were organized with four patients and 12 health care professionals, individual and group-wise.ResultsConsensus was reached on a pictograph illustrating the whole range of uncertainty for local recurrence risks, in combination with textual explanation that a more exact personalized risk would be given by their own physician. The pictograph consisted of 100 female icons in a 10 x 10 array. Icons with a stepwise gradient color indicated the uncertainty margin. The prevalence and severity of possible side-effects were explained using verbal labels.ConclusionsWe developed a novel way of visualizing uncertainties in recurrence rates in a patient decision aid. The effect of this way of communicating risk uncertainty is currently being tested in the BRASA study (NCT03375801).  相似文献   
87.
88.
Among the numerous signaling pathways involved in tumorigenesis, PI3K‐AKT‐mTOR is a key one that regulates diverse cellular functions. However, its prognostic value in esophageal carcinoma remains unclear. In our study, we examined the immunohistochemical expression of phosphorylated (p‐) AKT, mTOR, p70S6K and 4E‐BP1 along with the mutational status of PIK3CA and AKT1 genes by High Resolution Melting Analysis and Pyrosequencing in 44 esophageal carcinomas. The results were correlated with the clinicopathological characteristics of the patients in an effort to define their possible prognostic significance. Total p‐mTOR cytoplasmic expression, assessed in 10 random areas, was positively correlated with tumor stage (Kruskal–Wallis ANOVA, I/II vs III/IV, p = 0.0500). Μoreover, maximum p‐mTOR cytoplasmic immunoexpression, estimated in hot spot areas, was positively associated with tumor grade (Mann–Whitney U test, I/II vs III, p = 0.0565). Interestingly, p‐4E‐BP1 immunoreactivity was negatively correlated with tumor histological grade (Mann–Whitney U test, I/II vs III, p = 0.0427). No mutation was observed in exons 9 and 20 of PIK3CA gene and in exon 4 of AKT1 gene. In conclusion, our findings depict the presence of activated PI3K/AKT/mTOR pathway in esophageal cancer bringing forward p‐mTOR and p‐4E‐BP1 for their potential role in esophageal carcinogenesis. Additional studies are warranted to validate our findings.  相似文献   
89.
According to the current World Health Organization (WHO), renal cell carcinomas (RCCs) that primarily affect adults are classified into 8 major subtypes. Additional emerging entities in renal neoplasia have also been recently recognized and these are discussed in further detail by Mehra et al (Emerging Entities in Renal Neoplasia, Surgical Pathology Clinics, 2015, Volume 8, Issue 4). In most cases, the diagnosis of a RCC subtype can be based on morphologic criteria, but in some circumstances the use of ancillary studies can aid in the diagnosis. This review discusses the morphologic, genetic, and molecular findings in RCCs previously recognized by the WHO, and provides clues to distinction from each other and some of the newer subtypes of RCC. As prognosis and therapeutic options vary for the different subtypes of RCC, accurate pathologic distinction is critical for patient care.  相似文献   
90.
It has been suggested that tumour‐infiltrating lymphocytes (TILs) are associated with the progression of oral squamous cell carcinoma (OSCC). However, the prognostic value of TILs is inconclusive due to the heterogeneity of immune cells within the tumour microenvironment. In this meta‐analysis, we aimed to assess the prognostic value of TILs in OSCC. The PubMed, Cochrane, Embase, Scopus and Web of Science databases were searched up to April 20, 2019, and 33 studies were ultimately included in this meta‐analysis. Our pooled meta‐analysis showed that high infiltration of CD8+ TILs, CD45RO+ TILs and CD57+ TILs favoured better overall survival (OS). However, high infiltration of CD68+ macrophages and CD163+ macrophages was associated with poor prognosis in OSCC. These findings suggest that CD8+ TILs, CD45RO+ TILs, CD57+ TILs, CD68+ macrophages and CD163+ macrophages might serve as novel prognostic factors and therapeutic targets in OSCC.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号