全文获取类型
收费全文 | 10929篇 |
免费 | 865篇 |
国内免费 | 157篇 |
专业分类
耳鼻咽喉 | 299篇 |
儿科学 | 124篇 |
妇产科学 | 175篇 |
基础医学 | 1771篇 |
口腔科学 | 154篇 |
临床医学 | 785篇 |
内科学 | 2429篇 |
皮肤病学 | 345篇 |
神经病学 | 820篇 |
特种医学 | 754篇 |
外科学 | 1313篇 |
综合类 | 123篇 |
一般理论 | 5篇 |
预防医学 | 314篇 |
眼科学 | 168篇 |
药学 | 914篇 |
中国医学 | 134篇 |
肿瘤学 | 1324篇 |
出版年
2023年 | 98篇 |
2022年 | 262篇 |
2021年 | 414篇 |
2020年 | 245篇 |
2019年 | 309篇 |
2018年 | 384篇 |
2017年 | 315篇 |
2016年 | 490篇 |
2015年 | 634篇 |
2014年 | 669篇 |
2013年 | 731篇 |
2012年 | 1111篇 |
2011年 | 1081篇 |
2010年 | 672篇 |
2009年 | 532篇 |
2008年 | 658篇 |
2007年 | 636篇 |
2006年 | 530篇 |
2005年 | 440篇 |
2004年 | 401篇 |
2003年 | 322篇 |
2002年 | 280篇 |
2001年 | 88篇 |
2000年 | 76篇 |
1999年 | 62篇 |
1998年 | 47篇 |
1997年 | 43篇 |
1996年 | 25篇 |
1995年 | 15篇 |
1994年 | 21篇 |
1993年 | 15篇 |
1992年 | 32篇 |
1991年 | 33篇 |
1990年 | 27篇 |
1989年 | 31篇 |
1988年 | 12篇 |
1987年 | 31篇 |
1986年 | 10篇 |
1985年 | 21篇 |
1984年 | 8篇 |
1983年 | 11篇 |
1982年 | 10篇 |
1981年 | 11篇 |
1979年 | 7篇 |
1978年 | 13篇 |
1977年 | 9篇 |
1974年 | 8篇 |
1970年 | 7篇 |
1969年 | 9篇 |
1968年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Hyun Jong Choi Jong Ho Moon Yun Nah Lee Hyun Su Kim Ji Su Ha Tae Hoon Lee Sang‐Woo Cha Young Deok Cho Sang‐Heum Park 《Digestive endoscopy》2015,27(7):772-775
Direct peroral cholangioscopy (POC) using an ultra‐slim upper endoscope is one modality of POC for intraductal endoscopic evaluation and treatment of the bile duct. Choledochoduodenostomy (CDS) is one modality of biliary bypass surgery that provides a new route to the bile duct. We carried out direct POC using an ultra‐slim upper endoscope without the use of accessories in 10 patients (four sump syndromes, three bile duct strictures and three intrahepatic duct stones) previously undergoing surgical CDS. Direct POC was successful in all patients. The use of an intraductal balloon catheter was required in one patient for advancement of the endoscope into the bile duct. Distal bile ducts with sump syndromes were cleared using baskets and water irrigation under direct POC. Cholangiocarcinoma was diagnosed in one patient with hilar bile duct stricture after cholangioscopic evaluation and a targeting forceps biopsy under direct POC. Intrahepatic duct stones were successfully extracted after intraductal fragmentation under direct POC. Oozing bleeding occurred during intraductal lithotripsy but stopped spontaneously. Direct POC using an ultra‐slim upper endoscope without the assistance of accessories can easily be carried out in patients undergoing CDS. 相似文献
2.
Xin Yi Wong Andrew Qi Jun Lim Qianyu Shen John Whay Kuang Chia Min Hoe Chew Wah Siew Tan 《Current medical research and opinion》2020,36(10):1677-1686
Abstract
Objective
Ras wild-type metastatic colorectal cancers (mCRC) may be treated with anti-vascular endothelial growth factor (VEGF) or anti-epidermal growth factor receptor (EGFR) agents. We aim to estimate patients’ preferences for mCRC treatment and relative importance of cost, efficacy improvement, avoidance of side effects and therapy convenience, and relative uptake between profiles that resemble Bevacizumab (anti-VEGF) and Cetuximab (anti-EGFR), two commonly prescribed mCRC targeted therapies. 相似文献3.
4.
Clinical clues for differential diagnosis between verruca plana and verruca plana‐like seborrheic keratosis
下载免费PDF全文
![点击此处可从《The Journal of dermatology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Won‐Jeong Kim Won‐Ku Lee Margaret Song Hoon‐Soo Kim Hyun‐Chang Ko Byung‐Soo Kim Moon‐Bum Kim 《The Journal of dermatology》2015,42(4):373-377
Sometimes the clinical differentiation between verruca plana (VP) and VP‐like seborrheic keratosis (SK) could be challenged. However, there have been no studies on this issue to date. The aim of this study was to elucidate clinical and dermoscopic differences between these two diseases, and also to suggest a diagnostic algorithm of VP and VP‐like SK without skin biopsy. The patients who had lesions clinically considered as VP or VP‐like SK were the target of our study. We took clinical and dermoscopic photos with informed consent and conducted a questionnaire. All patients had their diagnoses confirmed by biopsy. Thirty‐three patients were enrolled in our study. Seventeen patients were finally diagnosed with VP (51.5%) and 16 patients with VP‐like SK (48.5%). In clinical findings, VP‐like SK showed significantly more scattered distribution than VP (P = 0.039), which exhibited more clustered or grouped distribution (P = 0.039). In dermoscopic findings, brain‐like appearance was more commonly observed in VP‐like SK (P = 0.003) whereas VP showed more red dots or globular vessels (P = 0.017) and even‐colored light brown to yellow patch (P < 0.001). Sex, onset age, the size of each lesion, location, color and shape showed no significant differences between them (P > 0.05). Based on our results, we suggest a diagnostic algorithm using Koebner's phenomenon, dermoscopic findings, distribution of each lesion and biopsy for multiple VP‐like lesions in adults, and we think it will be a very useful diagnostic tool in daily clinical dermatological practice. 相似文献
5.
Clinical usefulness of intraductal ultrasonography for the management of acute biliary pancreatitis
下载免费PDF全文
![点击此处可从《Journal of gastroenterology and hepatology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
6.
Fur-Hsing Wen Jen-Shi Chen Wen-Chi Chou Wen-Cheng Chang Wen Chi Shen Chia-Hsun Hsieh Siew Tzuh Tang 《Journal of pain and symptom management》2019,57(1):64-72
Context
Family caregivers constitute a critical component of the end-of-life care system with considerable cost to themselves. However, the joint association of terminally ill cancer patients' symptom distress and functional impairment with caregivers' subjective caregiving burden, quality of life (QOL), and depressive symptoms remains unknown.Objectives/Methods
We used multivariate hierarchical linear modeling to simultaneously evaluate associations between five distinct patterns of conjoint symptom distress and functional impairment (symptom-functional states) and subjective caregiving burden, QOL, and depressive symptoms in a convenience sample of 215 family caregiver–patient dyads. Data were collected every 2 to 4 weeks over patients' last 6 months.Results
Caregivers of patients in the worst symptom-functional states (States 3–5) reported worse subjective caregiving burden and depressive symptoms than those in the best two states, but the three outcomes did not differ between caregivers of patients in State 3 and States 4–5. Caregivers of patients in State 5 endured worse subjective caregiving burden and QOL than those in State 4. Caregivers of patients in State 4 suffered worse subjective caregiving burden and depressive symptoms but comparable QOL to those in State 2.Conclusion
Patients' five distinct, conjoint symptom-functional states were significantly and differentially associated with their caregivers' worse subjective caregiving burden, QOL, and depressive symptoms while caring for patients over their last 6 months. 相似文献7.
Phytonutrients extracted from natural resources are receiving much attention among researchers due to their highly antioxidative characteristics which prevent several degenerative diseases including cardiovascular diseases and cancers. These nutraceutical compounds can be used in food, pharmaceutical and cosmetic products as natural antioxidants, preservatives, colourants and functional foods. Huge volume of food wastes are generated from the processing industry and these low-value food residues are rich in various phytonutrients worth recovering. This approach of valorisation reduces the generation of food wastes and is cost-effective considering the cheap feedstock, reduced waste management expenses and high market value of extracted compounds. In light of the health and safety risks posed by commonly used organic extraction solvents derived from the petrochemical industry, there is a need to recover the phytonutrients using green, sustainable and efficient solvents that are safe for human consumption. This work discusses ethyl lactate as a safe, green, efficient and potentially cheap solvent to recover phytonutrients from fruit and vegetable by-products. Ethyl lactate is compared with other organic solvents commonly used from the aspects of safety, environmental impacts and efficiency. Current challenges when employing ethyl lactate are also discussed. 相似文献
8.
Su Jeong Seong Jin Pyo Hong Bong-Jin Hahm Hong Jin Jeon Jee Hoon Sohn Jun Young Lee Maeng Je Cho 《Journal of Korean medical science》2015,30(11):1675-1681
While decreasing trend in gender differences in alcohol use disorders was reported in Western countries, the change in Asian countries is unknown. This study aims to explore the shifts in gender difference in alcohol abuse (AA) and dependence (AD) in Korea. We compared the data from two nation-wide community surveys to evaluate gender differences in lifetime AA and AD by Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). Face-to-face interviews using the Composite International Diagnostic Interview (CIDI) were applied to all subjects in 2001 (n=6,220) and 2011 (n=6,022). Male-to-female ratio of odds was decreased from 6.41 (95% CI, 4.81-8.54) to 4.37 (95% CI, 3.35-5.71) for AA and from 3.75 (95% CI, 2.96-4.75) to 2.40 (95% CI, 1.80-3.19) for AD. Among those aged 18-29, gender gap even became statistically insignificant for AA (OR, 1.59; 95% CI, 0.97-2.63) and AD (OR, 1.18; 95% CI, 0.80-2.41) in 2011. Men generally showed decreased odds for AD (0.55; 95% CI, 0.45-0.67) and women aged 30-39 showed increased odds for AA (2.13; 95% CI 1.18-3.84) in 2011 compared to 2001. Decreased AD in men and increased AA in women seem to contribute to the decrease of gender gap. Increased risk for AA in young women suggests needs for interventions. 相似文献
9.
Samo Lasi
Filip Szczepankiewicz Erica Dall'Armellina Arka Das Christopher Kelly Sven Plein Jürgen E. Schneider Markus Nilsson Irvin Teh 《NMR in biomedicine》2020,33(2)
Motion is a major confound in diffusion‐weighted imaging (DWI) in the body, and it is a common cause of image artefacts. The effects are particularly severe in cardiac applications, due to the nonrigid cyclical deformation of the myocardium. Spin echo‐based DWI commonly employs gradient moment‐nulling techniques to desensitise the acquisition to velocity and acceleration, ie, nulling gradient moments up to the 2nd order (M2‐nulled). However, current M2‐nulled DWI scans are limited to encode diffusion along a single direction at a time. We propose a method for designing b‐tensors of arbitrary shapes, including planar, spherical, prolate and oblate tensors, while nulling gradient moments up to the 2nd order and beyond. The design strategy comprises initialising the diffusion encoding gradients in two encoding blocks about the refocusing pulse, followed by appropriate scaling and rotation, which further enables nulling undesired effects of concomitant gradients. Proof‐of‐concept assessment of in vivo mean diffusivity (MD) was performed using linear and spherical tensor encoding (LTE and STE, respectively) in the hearts of five healthy volunteers. The results of the M2‐nulled STE showed that (a) the sequence was robust to cardiac motion, and (b) MD was higher than that acquired using standard M2‐nulled LTE, where diffusion‐weighting was applied in three orthogonal directions, which may be attributed to the presence of restricted diffusion and microscopic diffusion anisotropy. Provided adequate signal‐to‐noise ratio, STE could significantly shorten estimation of MD compared with the conventional LTE approach. Importantly, our theoretical analysis and the proposed gradient waveform design may be useful in microstructure imaging beyond diffusion tensor imaging where the effects of motion must be suppressed. 相似文献
10.