全文获取类型
收费全文 | 894805篇 |
免费 | 74361篇 |
国内免费 | 4149篇 |
专业分类
耳鼻咽喉 | 13088篇 |
儿科学 | 25013篇 |
妇产科学 | 25435篇 |
基础医学 | 127633篇 |
口腔科学 | 26030篇 |
临床医学 | 80325篇 |
内科学 | 168392篇 |
皮肤病学 | 17392篇 |
神经病学 | 71448篇 |
特种医学 | 36174篇 |
外国民族医学 | 190篇 |
外科学 | 138674篇 |
综合类 | 32147篇 |
现状与发展 | 8篇 |
一般理论 | 267篇 |
预防医学 | 69589篇 |
眼科学 | 21337篇 |
药学 | 68616篇 |
44篇 | |
中国医学 | 3689篇 |
肿瘤学 | 47824篇 |
出版年
2018年 | 8378篇 |
2015年 | 9364篇 |
2014年 | 13284篇 |
2013年 | 18870篇 |
2012年 | 25689篇 |
2011年 | 27029篇 |
2010年 | 16275篇 |
2009年 | 15026篇 |
2008年 | 24775篇 |
2007年 | 26766篇 |
2006年 | 26546篇 |
2005年 | 25874篇 |
2004年 | 24776篇 |
2003年 | 23800篇 |
2002年 | 22756篇 |
2001年 | 36444篇 |
2000年 | 37078篇 |
1999年 | 31494篇 |
1998年 | 9577篇 |
1997年 | 8958篇 |
1996年 | 8743篇 |
1995年 | 8259篇 |
1994年 | 7941篇 |
1992年 | 26797篇 |
1991年 | 26220篇 |
1990年 | 25727篇 |
1989年 | 24747篇 |
1988年 | 23294篇 |
1987年 | 22957篇 |
1986年 | 21792篇 |
1985年 | 21134篇 |
1984年 | 16386篇 |
1983年 | 13967篇 |
1982年 | 8836篇 |
1981年 | 8170篇 |
1980年 | 7630篇 |
1979年 | 16698篇 |
1978年 | 12074篇 |
1977年 | 10136篇 |
1976年 | 9291篇 |
1975年 | 10109篇 |
1974年 | 12615篇 |
1973年 | 12117篇 |
1972年 | 11523篇 |
1971年 | 10668篇 |
1970年 | 10194篇 |
1969年 | 9894篇 |
1968年 | 8890篇 |
1967年 | 8211篇 |
1966年 | 7640篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
Victoria L. Parker Matthew C. Winter John A. Tidy Barry W. Hancock Julia E. Palmer Naveed Sarwar Baljeet Kaur Katie McDonald Xianne Aguiar Kamaljit Singh Nick Unsworth Imran Jabbar Allan A. Pacey Robert F. Harrison Michael J. Seckl 《International journal of cancer. Journal international du cancer》2023,152(5):986-997
Gestational trophoblastic neoplasia (GTN) patients are treated according to the eight-variable International Federation of Gynaecology and Obstetrics (FIGO) scoring system, that aims to predict first-line single-agent chemotherapy resistance. FIGO is imperfect with one-third of low-risk patients developing disease resistance to first-line single-agent chemotherapy. We aimed to generate simplified models that improve upon FIGO. Logistic regression (LR) and multilayer perceptron (MLP) modelling (n = 4191) generated six models (M1-6). M1, all eight FIGO variables (scored data); M2, all eight FIGO variables (scored and raw data); M3, nonimaging variables (scored data); M4, nonimaging variables (scored and raw data); M5, imaging variables (scored data); and M6, pretreatment hCG (raw data) + imaging variables (scored data). Performance was compared to FIGO using true and false positive rates, positive and negative predictive values, diagnostic odds ratio, receiver operating characteristic (ROC) curves, Bland-Altman calibration plots, decision curve analysis and contingency tables. M1-6 were calibrated and outperformed FIGO on true positive rate and positive predictive value. Using LR and MLP, M1, M2 and M4 generated small improvements to the ROC curve and decision curve analysis. M3, M5 and M6 matched FIGO or performed less well. Compared to FIGO, most (excluding LR M4 and MLP M5) had significant discordance in patient classification (McNemar's test P < .05); 55-112 undertreated, 46-206 overtreated. Statistical modelling yielded only small gains over FIGO performance, arising through recategorisation of treatment-resistant patients, with a significant proportion of under/overtreatment as the available data have been used a priori to allocate primary chemotherapy. Streamlining FIGO should now be the focus. 相似文献
13.
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
14.
目的:比较康莱特注射液联合紫杉醇及紫杉醇单纯化疗治疗晚期恶性胸腺瘤的不良反应和疗效。方法:2013年8月至2017年12月,经病理学和免疫组化确诊为恶性胸腺瘤并在我院肿瘤中心进行姑息性化疗的患者68例。康莱特注射液联合化疗为观察组(37例);单纯化疗为对照组(31例)。28天为一周期,共化疗4周期。结果:两组患者均无人发生过敏反应。观察组可有效减轻患者化疗不良反应:恶性、呕吐、四肢麻木、关节肌肉酸痛和白细胞下降(P<0.05),可以有效减轻患者胸闷症状和全身疼痛(P<0.05),在肿瘤控制方面,康莱特联合化疗的疗效较单纯化疗稍好,但均未见有统计学差异(P>0.05)。结论:康莱特注射液联合紫杉醇治疗晚期胸腺瘤,具有减轻患者疼痛、减轻化疗不良反应,从而提高患者化疗依从性的作用,值得临床进一步推广和研究。 相似文献
15.
16.
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.
17.
18.
Robert C. Lynall J. Troy Blackburn Kevin M. Guskiewicz Stephen W. Marshall Prudence Plummer Jason P. Mihalik 《Journal of Science and Medicine in Sport》2019,22(5):503-508
Objectives
Despite evidence for increased musculoskeletal injury after concussion recovery, there is a lack of dynamic balance assessments that could inform management and research into this increased injury risk post-concussion. Our purpose was to identify tandem gait dynamic balance deficits in recreational athletes with a concussion history within the past 18-months compared to matched controls.Design
Cross-sectional, laboratory study.Methods
Fifteen participants with a concussion history (age: 19.7 ± 0.9 years; 9 females; median time since concussion 126 days, range 28–432 days), and 15 matched controls (19.7 ± 1.6 years; 9 females) with no recent concussion history participated. We measured center-of-pressure (COP) outcomes (velocity, path length, speed, dual-task cost) under 4 tandem gait conditions: (1) tandem gait, (2) tandem gait, eyes closed, (3) tandem gait, eyes open, cognitive distraction, and (4) tandem gait, eyes closed, cognitive distraction.Results
The concussion history group demonstrated slower tandem gait velocity compared to the control group (4.0 cm/s difference), thus velocity was used as a covariate when analyzing COP path length and speed. The concussion history group (23.5%) demonstrated greater COP speed dual-task cost than the control group (16.3%) during the eyes closed dual-task condition. No other comparisons were statistically significant.Conclusions
There may be subtle dynamic balance differences during tandem gait that are detectable after return-to-activity following concussion, but the clinical significance of these findings is unclear. Longitudinal investigations should identify acute movement deficits in varying visual and cognitive scenarios after concussion in comparison with recovery on traditional concussion assessment tools while also recording musculoskeletal injury outcomes. 相似文献19.
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
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
20.
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