全文获取类型
收费全文 | 1798381篇 |
免费 | 134967篇 |
国内免费 | 3146篇 |
专业分类
耳鼻咽喉 | 26518篇 |
儿科学 | 50386篇 |
妇产科学 | 48262篇 |
基础医学 | 259045篇 |
口腔科学 | 54839篇 |
临床医学 | 157094篇 |
内科学 | 344785篇 |
皮肤病学 | 37808篇 |
神经病学 | 145074篇 |
特种医学 | 71883篇 |
外国民族医学 | 254篇 |
外科学 | 286268篇 |
综合类 | 40393篇 |
现状与发展 | 3篇 |
一般理论 | 518篇 |
预防医学 | 129189篇 |
眼科学 | 42302篇 |
药学 | 137194篇 |
3篇 | |
中国医学 | 3663篇 |
肿瘤学 | 101013篇 |
出版年
2018年 | 17928篇 |
2016年 | 16262篇 |
2015年 | 17963篇 |
2014年 | 24437篇 |
2013年 | 37103篇 |
2012年 | 50256篇 |
2011年 | 53143篇 |
2010年 | 31050篇 |
2009年 | 28384篇 |
2008年 | 51165篇 |
2007年 | 54677篇 |
2006年 | 54975篇 |
2005年 | 53478篇 |
2004年 | 51867篇 |
2003年 | 50237篇 |
2002年 | 48842篇 |
2001年 | 86740篇 |
2000年 | 89999篇 |
1999年 | 74508篇 |
1998年 | 19919篇 |
1997年 | 17790篇 |
1996年 | 17583篇 |
1995年 | 16459篇 |
1994年 | 15458篇 |
1993年 | 14378篇 |
1992年 | 58135篇 |
1991年 | 56161篇 |
1990年 | 54820篇 |
1989年 | 53341篇 |
1988年 | 49282篇 |
1987年 | 48315篇 |
1986年 | 45283篇 |
1985年 | 43863篇 |
1984年 | 32731篇 |
1983年 | 27892篇 |
1982年 | 16228篇 |
1981年 | 14562篇 |
1979年 | 31090篇 |
1978年 | 21779篇 |
1977年 | 18613篇 |
1976年 | 16607篇 |
1975年 | 18167篇 |
1974年 | 22290篇 |
1973年 | 21192篇 |
1972年 | 20114篇 |
1971年 | 18903篇 |
1970年 | 17972篇 |
1969年 | 17320篇 |
1968年 | 15625篇 |
1967年 | 14344篇 |
排序方式: 共有10000条查询结果,搜索用时 734 毫秒
11.
Boffa Joseph W. Tock Jamie L. Morabito Danielle M. Schmidt Norman B. 《Cognitive therapy and research》2022,46(5):1016-1029
Cognitive Therapy and Research - Despite interest in psychological inflexibility as a marker of suicide risk, no measure of psychological inflexibility specific to SI exists. The present study... 相似文献
12.
13.
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
14.
Marike Gabrielson Mattias Hammarström Magnus Bäcklund Jenny Bergqvist Kristina Lång Ann H Rosendahl Signe Borgquist Roxanna Hellgren Kamila Czene Per Hall 《International journal of cancer. Journal international du cancer》2023,152(11):2362-2372
Tamoxifen prevents recurrence of breast cancer and is suggested for preventive risk-reducing therapy. Tamoxifen reduces mammographic density, a proxy for therapy response, but little is known about its effects in remodelling normal breast tissue. Our study, a substudy within the double-blinded dose-determination trial KARISMA, investigated tamoxifen-specific changes in breast tissue composition and histological markers in healthy women. We included 83 healthy women randomised to 6 months daily intake of 20, 10, 5, 2.5, 1 mg of tamoxifen or placebo. The groups were combined to “no dose” (0-1 mg), “low-dose” (2.5-5 mg) or “high-dose” (10-20 mg) of tamoxifen. Ultrasound-guided biopsies were collected before and after tamoxifen exposure. In each biopsy, epithelial, stromal and adipose tissues was quantified, and expression of epithelial and stromal Ki67, oestrogen receptor (ER) and progesterone receptor (PR) analysed. Mammographic density using STRATUS was measured at baseline and end-of-tamoxifen-exposure. We found that different doses of tamoxifen reduced mammographic density and glandular-epithelial area in premenopausal women and associated with reduced epithelium and increased adipose tissue. High-dose tamoxifen also decreased epithelial ER and PR expressions in premenopausal women. Premenopausal women with the greatest reduction in proliferation also had the greatest epithelial reduction. In postmenopausal women, high-dose tamoxifen decreased the epithelial area with no measurable density decrease. Tamoxifen at both low and high doses influences breast tissue composition and expression of histological markers in the normal breast. Our findings connect epithelial proliferation with tissue remodelling in premenopausal women and provide novel insights to understanding biological mechanisms of primary prevention with tamoxifen. 相似文献
15.
Troppmair Teresa Egger J. Krösbacher A. Zanvettor A. Schinnerl A. Neumayr A. Baubin M. 《Der Anaesthesist》2022,71(4):272-280
Die Anaesthesiologie - Die Qualität eines Rettungssystems zeichnet sich auch durch den effizienten Einsatz seiner personellen und Fahrzeugressourcen aus. So können im berechtigten Fall... 相似文献
16.
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
17.
Brittney H. Cotta Margaret F. Meagher Aaron Bradshaw Stephen T. Ryan Gerant Rivera-Sanfeliz 《Expert review of anticancer therapy》2019,19(4):301-308
Introduction: Percutaneous renal mass biopsy has evolved over the last decade with improvements on previous pitfalls including low tissue yield, high non-diagnostic rates, and complications. As understanding of tumor biology and natural history of renal cortical neoplasms has improved, percutaneous renal mass biopsy is poised to have an expanding role in an area characterized by individualized management and refined risk stratification.
Areas covered: This review summarizes the evolution of renal mass biopsy to its current state with respect to outcomes, indications, and clinical guidelines.
Expert opinion: With improved understanding of differential biological potential of renal cortical neoplasms combined with technical improvements in diagnostic yield and accuracy, utilization of renal mass biopsy is becoming an important adjunct to patient care in a broad range of clinical scenarios, including active surveillance, thermal ablation, and use of primary systemic therapy in localized and advanced settings. 相似文献
18.
19.
20.