全文获取类型
收费全文 | 2474篇 |
免费 | 218篇 |
国内免费 | 20篇 |
专业分类
耳鼻咽喉 | 11篇 |
儿科学 | 87篇 |
妇产科学 | 94篇 |
基础医学 | 276篇 |
口腔科学 | 60篇 |
临床医学 | 227篇 |
内科学 | 489篇 |
皮肤病学 | 45篇 |
神经病学 | 175篇 |
特种医学 | 86篇 |
外科学 | 584篇 |
综合类 | 73篇 |
一般理论 | 6篇 |
预防医学 | 212篇 |
眼科学 | 28篇 |
药学 | 146篇 |
肿瘤学 | 113篇 |
出版年
2023年 | 26篇 |
2022年 | 31篇 |
2021年 | 49篇 |
2020年 | 25篇 |
2019年 | 59篇 |
2018年 | 52篇 |
2017年 | 49篇 |
2016年 | 54篇 |
2015年 | 52篇 |
2014年 | 60篇 |
2013年 | 73篇 |
2012年 | 128篇 |
2011年 | 140篇 |
2010年 | 82篇 |
2009年 | 81篇 |
2008年 | 141篇 |
2007年 | 147篇 |
2006年 | 118篇 |
2005年 | 116篇 |
2004年 | 118篇 |
2003年 | 99篇 |
2002年 | 99篇 |
2001年 | 48篇 |
2000年 | 37篇 |
1999年 | 39篇 |
1998年 | 34篇 |
1997年 | 31篇 |
1996年 | 33篇 |
1995年 | 30篇 |
1994年 | 26篇 |
1993年 | 20篇 |
1992年 | 44篇 |
1991年 | 49篇 |
1990年 | 43篇 |
1989年 | 36篇 |
1988年 | 30篇 |
1987年 | 23篇 |
1986年 | 32篇 |
1985年 | 36篇 |
1984年 | 19篇 |
1983年 | 16篇 |
1981年 | 13篇 |
1979年 | 29篇 |
1978年 | 19篇 |
1977年 | 17篇 |
1975年 | 13篇 |
1974年 | 15篇 |
1973年 | 20篇 |
1972年 | 13篇 |
1966年 | 17篇 |
排序方式: 共有2712条查询结果,搜索用时 15 毫秒
71.
72.
Leprosy remains an important health problem worldwide. The disease is caused by a chronic granulomatous infection of the skin and peripheral nerves with Mycobacterium leprae. The clinical range from tuberculoid to lepromatous leprosy is a result of variation in the cellular immune response to the mycobacterium. The resulting impairment of nerve function causes the disabilities associated with leprosy. This review summarises recent advances in understanding of the biology of leprosy, clinical features of the disease, the current diagnostic criteria, and the new approaches to treatment of the infection and the immune-mediated complications. Supervised multi-drug therapy (MDT) for fixed durations is highly effective for all forms of the disease. The widespread implementation of MDT has been associated with a fall in the prevalence of the leprosy but as yet no reduction in the case-detection rate globally. Thus, leprosy control activities must be maintained for decades to interrupt transmission of infection. 相似文献
73.
74.
75.
Zeeshan Butt Jin-Shei Lai Jennifer L. Beaumont Karen Kaiser Rajiv Mallick David Cella Jennifer L. Steel 《Quality of life research》2014,23(9):2447-2455
Purpose
Due to diagnosis at advanced stages, comorbidities, and the impact of treatment, patients with hepatocellular carcinoma (HCC) may experience pain. The purpose of this study was to evaluate the psychometric properties of a brief, clinically relevant measure of pain in HCC.Methods
We conducted a secondary data analysis from four longitudinal studies of patients with HCC (total n = 304). All patients completed the FACT-Hepatobiliary (FACT-Hep) questionnaire, and 49 patients completed the Brief Pain Inventory (BPI) Interference scale. We conducted confirmatory factor analysis (CFA), Rasch modeling, and correlational analysis to assess the psychometrics of the three items on the FACT-Hep that assess HCC-relevant pain scale.Results
Patients had an average age of 63.5 (±12.2) and were mostly male (76 %). The mean three-item pain subscale score was 8.5 ± 3.0. Seventy-four (24.3 %) patients reported no pain (score = 12). Results of a one-factor CFA supported unidimensionality of the items, and all items fit the Rasch model. An item-person map demonstrated that the three items covered all patients with non-extreme scores. Pain scores were significantly associated with baseline general health-related quality of life (FACT-General, r = 0.60, p < 0.001) and pain interference (BPI, r = ?0.63, p < 0.001).Conclusions
The three FACT-Hep pain items are unidimensional, cover the range of pain experienced by most patients with HCC, and demonstrate convergent validity. This pain subscale is, if future research demonstrates its sensitivity to change, potentially useful for HCC clinical trials. 相似文献76.
77.
Iris Cervenka Marie Al Rahmoun Yahya Mahamat-Saleh Agnès Fournier Marie-Christine Boutron-Ruault Gianluca Severi Saverio Caini Domenico Palli Reza Ghiasvand Marit B. Veierod Edoardo Botteri Anne Tjønneland Anja Olsen Renée T. Fortner Rudolf Kaaks Matthias B. Schulze Salvatore Panico Antonia Trichopoulou Clio Dessinioti Katerina Niforou Sabina Sieri Rosario Tumino Carlotta Sacerdote Bas Bueno-de-Mesquita Torkjel M. Sandanger Sandra Colorado-Yohar Maria J. Sánchez Leire Gil Majuelo Leila Lujan-Barroso Eva Ardanaz Susana Merino Karolin Isaksson Salma Butt Ingrid Ljuslinder Malin Jansson Ruth C. Travis Kay-Tee Khaw Elisabete Weiderpass Laure Dossus Sabina Rinaldi Marina Kvaskoff 《International journal of cancer. Journal international du cancer》2020,146(12):3267-3280
Evidence suggests an influence of sex hormones on cutaneous melanoma risk, but epidemiologic findings are conflicting. We examined the associations between use of oral contraceptives (OCs) and menopausal hormone therapy (MHT) and melanoma risk in women participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). EPIC is a prospective cohort study initiated in 1992 in 10 European countries. Information on exogenous hormone use at baseline was derived from country-specific self-administered questionnaires. We used Cox proportional hazards regression models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). Over 1992–2015, 1,696 melanoma cases were identified among 334,483 women, whereof 770 cases among 134,758 postmenopausal women. There was a positive, borderline-significant association between OC use and melanoma risk (HR = 1.12, 95% CI = 1.00–1.26), with no detected heterogeneity across countries (phomogeneity = 0.42). This risk increased linearly with duration of use (ptrend = 0.01). Among postmenopausal women, ever use of MHT was associated with a nonsignificant increase in melanoma risk overall (HR = 1.14, 95% CI = 0.97–1.43), which was heterogeneous across countries (phomogeneity = 0.05). Our findings do not support a strong and direct association between exogenous hormone use and melanoma risk. In order to better understand these relations, further research should be performed using prospectively collected data including detailed information on types of hormone, and on sun exposure, which may act as an important confounder or effect modifier on these relations. 相似文献
78.
The incorporation of inorganic oxide fillers imparts superior dielectric properties in silicone rubber for high-voltage insulation. However, the dielectric characteristics are influenced by the mechanical stress. The effects of ramped compression on the dielectric properties of neat silicone rubber (NSiR), 15% SiO2 microcomposite (SSMC), 15% alumina trihydrate (ATH) microcomposite (SAMC) and 10% ATH + 2% SiO2 hybrid composite (SMNC) are presented in this study. The dielectric constant and dissipation factor were measured before and after each compression especially in the frequency range of 50 kHz to 2MHz. Before the compression, SSMC expressed the highest dielectric constant of 4.44 followed by SMNC and SAMC. After the compression cycle, SAMC expressed a better dielectric behavior exhibiting dielectric constant of 7.19 and a dissipation factor of 0.01164. Overall, SAMC expressed better dielectric response before and after compression cycle with dielectric constant and dissipation factor in admissible ranges. 相似文献
79.
Nelleke G. Langerak Robert P. Lamberts A. Graham Fieggen Jonathan C. Peter Warwick J. Peacock Christopher L. Vaughan 《Child's nervous system》2007,23(9):1003-1006
Introduction Given the large number of cerebral palsy patients who have undergone selective dorsal rhizotomy in the past two decades, it
is clearly imperative that the clinical community be provided with objective and compelling evidence of the long-term sequelae
of the procedure.
Materials and methods In the early 1980s, Peacock in Cape Town shifted the site of the rhizotomy from the conus medullaris to the cauda equina,
and in the past 25 years, more than 200 children have been operated on. We have studied the incidence of spinal deformities
after multiple-level laminectomy and recorded a 20% incidence of isthmic spondylolysis or grade-I spondylolisthesis. We have
also conducted a long-term prospective gait analysis study on a cohort of 14 ambulatory patients who were operated on in 1985.
Results Ten years after surgery, our patients had increased ranges of motion that were within normal limits. Step length was significantly
improved, although cadence was unchanged postoperatively and was significantly less than normal age-matched control subjects.
Discussion We have recently tracked down all 14 patients from the original cohort and are currently completing a 20-year prospective
follow-up analysis of their neuromuscular function and gait. Our preliminary data suggest that selective dorsal rhizotomy
is not only an effective method for alleviating spasticity but it also leads to long-term functional benefits. 相似文献
80.
A retrospective study was performed to determine whether bone blood supply can be assessed on gadolinium-enhanced magnetic resonance imaging. Lumbar spine magnetic resonance imaging (MRI) examinations of 49 patients attending for post-laminectomy examination were reviewed (30 male, 19 female, mean age 46.4 years, age range 23–84 years). Each study included sagittal T1-weighted spin echo sequences before and after gadolinium administration. Regions of interest were drawn within the L3 vertebral body from a parasagittal slice from each sequence. Signal intensity (SI) values were ascertained and the percentage increase in SI was calculated. For each patient, changes in receiver gain for pre and post-gadolinium images were corrected by an image scaling factor. In all cases, a measurable increase in SI was found (mean 15.3%, range 4.4–55.7) due to bone vascularity. The results give no indication of the quantity or timing of blood supply but provide a basis for further work. 相似文献