全文获取类型
收费全文 | 991801篇 |
免费 | 84968篇 |
国内免费 | 10885篇 |
专业分类
耳鼻咽喉 | 13807篇 |
儿科学 | 26444篇 |
妇产科学 | 26489篇 |
基础医学 | 136322篇 |
口腔科学 | 28016篇 |
临床医学 | 93842篇 |
内科学 | 180073篇 |
皮肤病学 | 18558篇 |
神经病学 | 74620篇 |
特种医学 | 39706篇 |
外国民族医学 | 215篇 |
外科学 | 146209篇 |
综合类 | 53759篇 |
现状与发展 | 42篇 |
一般理论 | 270篇 |
预防医学 | 79120篇 |
眼科学 | 24126篇 |
药学 | 79895篇 |
232篇 | |
中国医学 | 12282篇 |
肿瘤学 | 53627篇 |
出版年
2021年 | 11440篇 |
2020年 | 8510篇 |
2019年 | 9131篇 |
2018年 | 11278篇 |
2017年 | 10235篇 |
2016年 | 10252篇 |
2015年 | 13959篇 |
2014年 | 18746篇 |
2013年 | 24626篇 |
2012年 | 34448篇 |
2011年 | 36234篇 |
2010年 | 23457篇 |
2009年 | 21011篇 |
2008年 | 31273篇 |
2007年 | 33002篇 |
2006年 | 31899篇 |
2005年 | 30708篇 |
2004年 | 28056篇 |
2003年 | 26874篇 |
2002年 | 25208篇 |
2001年 | 38351篇 |
2000年 | 38558篇 |
1999年 | 32506篇 |
1998年 | 10160篇 |
1997年 | 9517篇 |
1996年 | 9217篇 |
1995年 | 8636篇 |
1992年 | 26956篇 |
1991年 | 26387篇 |
1990年 | 25868篇 |
1989年 | 24868篇 |
1988年 | 23402篇 |
1987年 | 23046篇 |
1986年 | 21839篇 |
1985年 | 21173篇 |
1984年 | 16425篇 |
1983年 | 14031篇 |
1982年 | 8869篇 |
1979年 | 16747篇 |
1978年 | 12115篇 |
1977年 | 10182篇 |
1976年 | 9329篇 |
1975年 | 10151篇 |
1974年 | 12643篇 |
1973年 | 12140篇 |
1972年 | 11538篇 |
1971年 | 10685篇 |
1970年 | 10218篇 |
1969年 | 9910篇 |
1968年 | 8901篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
21.
Guo-Quan Shi Huajun Zhu & Zhen-Guo Yan 《Communications In Computational Physics》2022,31(4):1215-1241
A priori subcell limiting approach is developed for high-order flux reconstruction/correction procedure via reconstruction (FR/CPR) methods on two-dimensional unstructured quadrilateral meshes. Firstly, a modified indicator based on
modal energy coefficients is proposed to detect troubled cells, where discontinuities
exist. Then, troubled cells are decomposed into nonuniform subcells and each subcell has one solution point. A second-order finite difference shock-capturing scheme
based on nonuniform nonlinear weighted (NNW) interpolation is constructed to perform the calculation on troubled cells while smooth cells are calculated by the CPR
method. Numerical investigations show that the proposed subcell limiting strategy on
unstructured quadrilateral meshes is robust in shock-capturing. 相似文献
22.
Phoebe Hammer Kevin White Stephanie Mengden Vessy Korcheva Philipp W. Raess 《Journal of cutaneous pathology》2019,46(5):343-346
Cutaneous leiomyomas are rare benign smooth‐muscle tumors. These lesions are distinguished based on their cell of origin and are subclassified as pilar leiomyoma, angioleiomyoma, and genital‐type leiomyoma. Nipple leiomyoma is the least common genital‐type leiomyoma, arising from the dartoic muscle cell of the nipple. Histologic examination of the lesion is necessary for definitive diagnosis, and these uncommon tumors can pose a diagnostic challenge. We describe herein a series of six nipple leiomyomas with a spectrum of histologic appearances. 相似文献
23.
24.
25.
Yan Gao Shi-Feng Chu Zhao Zhang Qi-Di Ai Cong-Yuan Xia Hui-Yong Huang 《Journal of Asian natural products research》2019,21(8):782-797
Inappropriate use of acetaminophen (APAP) can lead to morbidity and mortality secondary to hepatic necrosis. Ginsenoside Rg1 is a major active ingredient in processed Panax ginseng, which is proved to elicit biological effects. We hypothesized the beneficial effect of Rg1 on APAP-mediated hepatotoxicity was through Nrf2/ARE pathway. The study was conducted in cells and mice, comparing the actions of Rg1. Rg1 significantly improved cell survival rates and promoted the expression of antioxidant proteins. Meanwhile, Rg1 reduced the excessive ROS and the occurrence of cell apoptosis, which were related to Nrf2/ARE pathway. Expression of Nrf2 has a certain cell specificity.
26.
27.
目的探讨脑卒中患者急性应激障碍发生现状及影响因素。方法采用斯坦福急性应激反应问卷对349例脑卒中住院患者进行调查。结果共163例(46.70%)患者发生急性应激障碍;Logistic回归分析结果显示,患者性格、是否存在偏瘫及是否吞咽功能障碍是脑卒中患者发生急性应激障碍的主要影响因素(P0.05,P0.01)。结论脑卒中患者急性应激障碍发生率较高,内向性格及存在偏瘫和吞咽功能障碍的患者更容易发生急性应激障碍。医护人员应及时为高危患者提供个体化治疗及预见性护理,防止脑卒中患者发生急性应激障碍。 相似文献
28.
Prevalence of HER2 Expression and Its Correlation with Clinicopathological Parameters in Gastric or Gastroesophageal Junction Adenocarcinoma in North-East Indian Population
下载免费PDF全文
![点击此处可从《Asian Pacific journal of cancer prevention》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Partha S RoyTomar NyoduMunlima HazarikaB J SaikiaC BhuyanAmit InamdarC W NyutheB BorthakurJ D Sharma 《Asian Pacific journal of cancer prevention》2019,20(4):1139-1145
Objective: Human epidermal growth factor receptor 2 (erbb2/HER2) overexpression, has now been implicatedin advanced gastric and gastroesophageal junction cancers. The study was conducted to determine the rate of HER2positivity in patients with locally advanced or metastatic gastric and gastroesophageal adenocarcinoma in North-EastIndia and to assess the impact of various demographic and clinical parameters on HER2 positivity. Methods: A total of68 patients of age >18 years of gastric and gastroesophageal adenocarcinoma diagnosed on histopathological examinationfrom September 2016 to February 2018 at Dr B Borooah Cancer Institute, Assam were enrolled for the observational(epidemiological) study. All patients were subjected to the HER2 immunohistochemistry test using a FDA-approved,standardized test kit. HER2 expression was correlated with various demographic and clinicopathological parameters.Results: The overall rate of HER2 positivity in the population studied was 56% (n=38). The rate was non-significantlyhigher in male, older age group (>60 years) and Hindu population. Similarly, HER2 positivity rate was higher in patientswith well differentiated histology and was more common in patients with stage II and III diseases, but neither of theassociations is statistically significant. HER2 positivity rate was significantly higher in proximal and in GEJ tumours(56% versus 44%, P=0.002). Conclusion: HER2 overexpression was evident in 56% of the North-East Indian patientswith locally advanced and metastatic gastric and gastroesophageal adenocarcinoma. The overexpression correlatedsignificantly with primary tumour site. Routine testing of gastric and gastroesophageal tumours for HER2 expressionis recommended to provide a therapeutic advantage in Indian patients. 相似文献
29.
Whitney S. Brandt Wanpu Yan Jian Zhou Kay See Tan Joseph Montecalvo Bernard J. Park Prasad S. Adusumilli James Huang Matthew J. Bott Valerie W. Rusch Daniela Molena William D. Travis Mark G. Kris Jamie E. Chaft David R. Jones 《The Journal of thoracic and cardiovascular surgery》2019,157(2):743-753.e3
Objective
Comparative survival between neoadjuvant chemotherapy and adjuvant chemotherapy for patients with cT2-4N0-1M0 non–small cell lung cancer has not been extensively studied.Methods
Patients with cT2-4N0-1M0 non–small cell lung cancer who received platinum-based chemotherapy were retrospectively identified. Exclusion criteria included stage IV disease, induction radiotherapy, and targeted therapy. The primary end point was disease-free survival. Secondary end points were overall survival, chemotherapy tolerance, and ability of Response Evaluation Criteria In Solid Tumors response to predict survival. Survival was estimated using the Kaplan–Meier method, compared using the log-rank test and Cox proportional hazards models, and stratified using matched pairs after propensity score matching.Results
In total, 330 patients met the inclusion criteria (n = 92/group after propensity-score matching; median follow-up, 42 months). Five-year disease-free survival was 49% (95% confidence interval, 39-61) for neoadjuvant chemotherapy versus 48% (95% confidence interval, 38-61) for adjuvant chemotherapy (P = .70). On multivariable analysis, disease-free survival was not associated with neoadjuvant chemotherapy or adjuvant chemotherapy (hazard ratio, 1.1; 95% confidence interval, 0.64-1.90; P = .737), nor was overall survival (hazard ratio, 1.21; 95% confidence interval, 0.63-2.30; P = .572). The neoadjuvant chemotherapy group was more likely to receive full doses and cycles of chemotherapy (P = .014/0.005) and had fewer grade 3 or greater toxicities (P = .001). Response Evaluation Criteria In Solid Tumors response to neoadjuvant chemotherapy was associated with disease-free survival (P = .035); 15% of patients receiving neoadjuvant chemotherapy (14/92) had a major pathologic response.Conclusions
Timing of chemotherapy, before or after surgery, is not associated with an improvement in overall or disease-free survival among patients with cT2-4N0-1M0 non–small cell lung cancer who undergo complete surgical resection. 相似文献30.