全文获取类型
收费全文 | 21541篇 |
免费 | 1077篇 |
国内免费 | 193篇 |
专业分类
耳鼻咽喉 | 152篇 |
儿科学 | 378篇 |
妇产科学 | 177篇 |
基础医学 | 2469篇 |
口腔科学 | 426篇 |
临床医学 | 1281篇 |
内科学 | 6546篇 |
皮肤病学 | 493篇 |
神经病学 | 1490篇 |
特种医学 | 711篇 |
外科学 | 3905篇 |
综合类 | 77篇 |
一般理论 | 3篇 |
预防医学 | 467篇 |
眼科学 | 462篇 |
药学 | 1238篇 |
中国医学 | 46篇 |
肿瘤学 | 2490篇 |
出版年
2023年 | 180篇 |
2022年 | 338篇 |
2021年 | 592篇 |
2020年 | 338篇 |
2019年 | 457篇 |
2018年 | 498篇 |
2017年 | 397篇 |
2016年 | 491篇 |
2015年 | 513篇 |
2014年 | 678篇 |
2013年 | 818篇 |
2012年 | 1380篇 |
2011年 | 1540篇 |
2010年 | 892篇 |
2009年 | 684篇 |
2008年 | 1198篇 |
2007年 | 1386篇 |
2006年 | 1318篇 |
2005年 | 1258篇 |
2004年 | 1184篇 |
2003年 | 1110篇 |
2002年 | 1102篇 |
2001年 | 381篇 |
2000年 | 356篇 |
1999年 | 383篇 |
1998年 | 239篇 |
1997年 | 225篇 |
1996年 | 211篇 |
1995年 | 169篇 |
1994年 | 156篇 |
1993年 | 125篇 |
1992年 | 218篇 |
1991年 | 216篇 |
1990年 | 178篇 |
1989年 | 211篇 |
1988年 | 183篇 |
1987年 | 174篇 |
1986年 | 134篇 |
1985年 | 138篇 |
1984年 | 95篇 |
1983年 | 69篇 |
1982年 | 44篇 |
1981年 | 32篇 |
1980年 | 38篇 |
1979年 | 49篇 |
1976年 | 36篇 |
1972年 | 30篇 |
1969年 | 40篇 |
1968年 | 30篇 |
1967年 | 33篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Tatsuki Yoshimatsu Daisuke Yoshida Hiroyuki Shimada Taiki Komatsu Atsushi Harada Takao Suzuki 《Geriatrics & Gerontology International》2013,13(2):351-357
Aim: Near‐infrared spectroscopy (NIRS) allows estimation of the percentage of body fat (%BF) regardless of the patient's posture; thus, it is useful for assessment of elderly patients with severe decline of basic activity who cannot hold a standing position. However, the accuracy by which the near‐infrared light emitted from NIRS reflects subcutaneous tissue is unknown. The aim of this study was to assess how correctly NIRS reflects the subcutaneous fat and muscle thickness derived from ultrasonography in community‐dwelling elderly. Methods: A total of 93 community‐dwelling older adults aged 65 years and older were enrolled in this study (mean 75.8 years, 6.7 SD). Participants were assessed according to optical density (OD) measurements by NIRS, subcutaneous fat and muscle thickness by ultrasonography, and muscle strength. Pearson's correlation coefficients were calculated for each sex. Stepwise multiple regression analysis was used to identify factors that contributed to OD for each sex. Results: OD measured at the forearm and thigh were significantly correlated with subcutaneous fat thickness. In stepwise multiple regression analyses, subcutaneous fat thickness was found to be a significant determinant of OD in men (forearm β = −0.37, P = 0.01; thigh β = −0.63, P < 0.001) and women (forearm β = −0.50, P < 0.001; thigh: β = −0.52, P < 0.001). Conclusions: These results suggest that NIRS can appropriately estimate fat‐free mass. By adding other variables to OD as the predictive variable, skeletal muscle mass might be estimated in the elderly population. Geriatr Gerontol Int 2013; 13: 351–357 . 相似文献
992.
Yuji Kasamaki M.D. Yukio Ozawa M.D. Masakatsu Ohta M.D. Akira Sezai M.D. Takashi Yamaki B.A. Mutsuo Kaneko Ph.D. Ichiro Watanabe M.D. Atsushi Hirayama M.D. Tomohiro Nakayama M.D. 《Annals of noninvasive electrocardiology》2011,16(2):156-164
Background: The International Conference on Harmonization E14 Guideline specifies detailed assessment of QT interval or corrected QT interval prolongation when developing new drugs. We recently devised new software to precisely measure the QT interval. Methods and Results: The QT intervals of all leads for a selected single heart beat were compared between automated measurement with the new software from Fukuda Denshi and manual measurement. With both automated and manual measurement, QT intervals obtained by the tangent method were shorter than those obtained by the differential threshold method, but the extent of correction was smaller. QT interval data obtained by the differential threshold method were more similar to values obtained by visual measurement than were data obtained by the tangent method, but the extent of correction was larger. Variability was related to the T‐wave amplitude and to setting the baseline and tangent in the tangent method, while skeletal muscle potential noise affected the differential threshold method. Drift, low‐amplitude recordings, and T‐wave morphology were problems for both methods. Among the 12 leads, corrections were less frequent for leads II and V3–V6. Conclusion: We conclude that, for a thorough assessment of the QT/QTc interval, the tangent method or the differential threshold method appears to be suitable because of smaller interreader differences and better reproducibility. Correction of data should be done by readers who are experienced in measuring the QT interval. It is also important for electrocardiograms to have little noise and for a suitable heart rate and appropriate leads to be selected. Ann Noninvasive Electrocardiol 2011;16(2):156–164 相似文献
993.
994.
We report a case of Aicardi–Goutières syndrome with systemic lupus erythematosus and hypothyroidism. A 3-year-old girl, diagnosed with Aicardi–Goutières syndrome at 9 months, was transferred to our hospital for fever of unknown origin. Severe spasticity with dystonic posturing and flexion contracture of the limbs were noted. Interstitial pneumonia with pleural effusion was evident. Immunological investigations revealed positive antinuclear antibodies and reduced thyroid function. Prompt treatment with steroids, cyclophosphamide, and levothyroxine sodium hydrate elicited a good response. It is necessary to emphasize that its possible relationship between Aicardi–Goutières syndrome and systemic lupus erythematosus and/or hypothyroidism. 相似文献
995.
996.
Naomi Takeichi Sanae Midorikawa Atsushi Watanabe Banyar Than Naing Hideki Tamura Toshiko Wakakuri‐Kano Akira Ishizaki Hitoshi Sugihara Sumiko Nissato Yuria Saito Yuichi Aita Kiyo‐aki Ishii Takehito Igarashi Yasushi Kawakami Hisato Hara Tatsuhiko Ikeda Kazuo Shimizu Shinichi Suzuki Hitoshi Shimano Masashi Kawamoto Takashi Shimada Tsuyoshi Watanabe Shinichi Oikawa Kazuhiro Takekoshi 《Clinical endocrinology》2012,77(5):707-714
997.
998.
999.
1000.
Shoko Nakayama Taiji Yokote Kichinosuke Kobayashi Yuji Hirata Toshikazu Akioka Takuji Miyoshi Satoko Oka Nobuya Hiraoka Kazuki Iwaki Ayami Takayama Takayuki Takubo Motomu Tsuji Toshiaki Hanafusa 《European journal of haematology》2010,84(1):79-83
A 91‐year‐old woman presented with a rapidly proliferative cutaneous lesion on the left lower limb, which was identified as a primary cutaneous diffuse large B‐cell lymphoma (PCLBCL), leg type, on biopsy. The patient also showed complications of hepatomegaly, endocrinopathy, edema, skin change, and polyneuropathy without monoclonal plasma cell proliferative disorder, and was therefore diagnosed with POEMS‐like syndrome owing to the lack of monoclonal plasma cell proliferative disorder. Levels of serum vascular endothelial growth factor (VEGF) and interleukin‐6 (IL‐6) were high with the lymphoma cells immunostained positively for VEGF and IL‐6. To the best of our knowledge, this is the first case report of PCLBCL, leg type, with POEMS‐like syndrome. The findings in this case suggest that the symptoms of POEMS‐like syndrome might be caused by the cytokines produced by the lymphoma cells. Furthermore, a wider range of diagnostic criteria associated with the result of abnormal secretion of cytokine may have to be considered for the diagnosis and evaluation of patients with possible POEMS syndrome, as against the present criteria specifying monoclonal plasma cell proliferative disorder as the essential criterion. 相似文献