全文获取类型
收费全文 | 11616篇 |
免费 | 650篇 |
国内免费 | 51篇 |
专业分类
耳鼻咽喉 | 79篇 |
儿科学 | 170篇 |
妇产科学 | 179篇 |
基础医学 | 1599篇 |
口腔科学 | 523篇 |
临床医学 | 826篇 |
内科学 | 2770篇 |
皮肤病学 | 198篇 |
神经病学 | 836篇 |
特种医学 | 657篇 |
外科学 | 1868篇 |
综合类 | 52篇 |
预防医学 | 397篇 |
眼科学 | 234篇 |
药学 | 759篇 |
中国医学 | 10篇 |
肿瘤学 | 1160篇 |
出版年
2023年 | 50篇 |
2021年 | 153篇 |
2020年 | 102篇 |
2019年 | 118篇 |
2018年 | 226篇 |
2017年 | 168篇 |
2016年 | 202篇 |
2015年 | 193篇 |
2014年 | 234篇 |
2013年 | 299篇 |
2012年 | 532篇 |
2011年 | 575篇 |
2010年 | 288篇 |
2009年 | 271篇 |
2008年 | 497篇 |
2007年 | 472篇 |
2006年 | 523篇 |
2005年 | 506篇 |
2004年 | 469篇 |
2003年 | 490篇 |
2002年 | 532篇 |
2001年 | 423篇 |
2000年 | 465篇 |
1999年 | 454篇 |
1998年 | 148篇 |
1997年 | 116篇 |
1996年 | 102篇 |
1995年 | 82篇 |
1994年 | 98篇 |
1993年 | 102篇 |
1992年 | 320篇 |
1991年 | 310篇 |
1990年 | 273篇 |
1989年 | 276篇 |
1988年 | 289篇 |
1987年 | 248篇 |
1986年 | 233篇 |
1985年 | 210篇 |
1984年 | 160篇 |
1983年 | 101篇 |
1982年 | 54篇 |
1981年 | 53篇 |
1979年 | 122篇 |
1978年 | 66篇 |
1977年 | 60篇 |
1976年 | 58篇 |
1975年 | 61篇 |
1974年 | 57篇 |
1973年 | 55篇 |
1971年 | 52篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
Shintaro Ito Nobukazu Fuwa Miwako Nomura Suguru Ota Takayuki Morishima Takashi Daimon Yoshikazu Maeda Jun Ueda Iwai Tohnai Noriko Ii Tosiaki Miyati 《Auris, nasus, larynx》2021,48(3):496-501
ObjectiveIn cases of head and neck cancer treated with intra-arterial chemotherapy, no objective indices are available for determining the distribution of anticancer drugs administered to multiple arteries. To establish such indices, noninvasive measurements of drug concentrations are required in the arterial perfusion area of each artery. In MRI, changes in 1/T1 (Δ1/T1) are correlated with the contrast agent concentration. We focused on these properties and investigated whether it is possible to estimate anticancer drug concentrations within tissue based on Δ1/T1.MethodsWe employed the fast spin echo (FSE) sequence to determine optimum imaging parameters using a phantom. Subsequently, contrast agent was administered via the lingual and external carotid arteries for seven cases of tongue cancer. Δ1/T1 were then measured in tumor and nontumor tissues. The results of this study were compared with those of a previous study in which intratumor concentrations of anticancer agent were measured in excised specimens.ResultsThe optimum imaging parameters for the FSE was two repetition times (TR, 500 and 1000 ms). When compared with the external carotid artery administration, the lingual artery administration of contrast agent resulted in significantly higher Δ1/T1 in both tumor and nontumor tissues (2.13 and 2.62 times, respectively). The multiplying factor for the nontumor tissue and high homogeneity of the contrast agent concentration were reasonably consistent with the results of the previous study.ConclusionThis method can be applied to estimating intratissue concentrations of intra-arterially administered anticancer drugs, thus possibly providing useful information in determining the distribution of anticancer drugs. 相似文献
2.
3.
Hamano Yuki Maruyama Kazuichi Oie Yoshinori Maeda Naoyuki Koh Shizuka Hashida Noriyasu Nishida Kohji 《Japanese journal of ophthalmology》2022,66(4):358-364
Japanese Journal of Ophthalmology - To determine whether visual function, especially when dependent on the anterior segment of ocular tissue, is altered during high-dose steroid treatment for... 相似文献
4.
5.
Satoru Motoyama Eri Maeda Katsunori Iijima Akira Anbai Yusuke Sato Akiyuki Wakita Yushi Nagaki Hiromu Fujita Yoshihiro Minamiya Takahiro Higashi 《Cancer science》2021,112(10):4281-4291
To address the major issue of regional disparity in the treatment for elderly cancer patients in an aging society, we compared the treatment strategies used for elderly patients with thoracic esophageal cancer and their survival outcomes in metropolitan areas and other regions. Using the national database of hospital-based cancer registries in 2008-2011, patients aged 75 years or older who had been diagnosed with thoracic esophageal cancer were enrolled. We divided the patients into two groups: those treated in metropolitan areas (Tokyo, Kanagawa, Osaka, Aichi, Saitama, and Chiba prefectures) with populations of 6 million or more and those treated in other areas (the other 41 prefectures). Compared were patient backgrounds, treatment strategies, and survival curves at each cancer stage. In total, 1236 (24%) patients from metropolitan areas and 3830 (76%) patients from nonmetropolitan areas were enrolled. Patients in metropolitan areas were treated at more advanced stages. There was also a difference in treatment strategy. The 3-year survival rate among cStage I patients was better in metropolitan areas (71.6% vs. 63.7%), and this finding mainly reflected the survival difference between patients treated with radiotherapy alone. For cStage II-IV patients, there were no differences. Multivariable Cox proportional hazard analysis including interaction terms between treatment areas, cStage, and the first-line treatments revealed that treatments in the metropolitan areas were significantly associated with better survival among patients treated with radiotherapy alone for cStage I cancer. Treatment strategies for elderly patients with thoracic esophageal cancer and its survival outcomes differed between metropolitan areas and other regions. 相似文献
6.
Kohei Ashikaga Haruki Itoh Tomoko Maeda Hidetaka Itoh Yuri Ichikawa Shiori Tanaka Ryuichi Ajisaka Akira Koike Shigeru Makita Kazuto Omiya Yuko Kato Hitoshi Adachi Masatoshi Nagayama Akihiko Tajima Naomi Harada Yoshihiro J Akashi 《Journal of cardiology》2021,77(1):57-64
BackgroundThe current understanding of ventilator efficiency variables during ramp exercise testing in the normal Japanese population is insufficient, and the responses of tidal volume (VT) and minute ventilation (V?E) to the ramp exercise test in the normal Japanese population are not known.MethodsA total of 529 healthy Japanese subjects aged 20–78 years underwent cardiopulmonary exercise testing using a cycle ergometer with ramp protocols. VT and V?E at rest, at anaerobic threshold, and at peak exercise were determined. The slope of V?E versus carbon dioxide (V?CO2) (V?E vs. V?CO2 slope), minimum V?E/V?CO2, and oxygen uptake efficiency slope (OUES) were determined.ResultsFor males and females in their 20 s, peak VT (VTpeak) was 2192 ± 376 and 1509 ± 260 mL (p < 0.001), peak V?E (V?Epeak) was 80.6 ± 18.7 and 57.7 ± 13.9 L/min (sex differences p < 0.001), the V?E vs. V?CO2 slope was 24.4 ± 3.2 and 25.7 ± 3.2 (p = 0.035), the minimum V?E/V?CO2 was 24.2 ± 2.3 and 27.0 ± 2.8 (p < 0.001), and the OUES was 2452 ± 519 and 1991 ± 315 (p < 0.001), respectively. VTpeak and V?Epeak decreased with age and increased with weight and height. The V?E vs. V?CO2 slope and minimum V?E/V?CO2 increased with age, while conversely, the OUES decreased with age.ConclusionsWe have established the normal range of VT and V?E responses, the V?E vs. V?CO2 slope, the minimum V?E/V?CO2, and the OUES for a healthy Japanese population. Some of these parameters were influenced by weight, height, sex, and age. These results provide useful reference values for interpreting the results of cardiopulmonary exercise testing in cardiac patients. 相似文献
7.
Hosokawa Shinobu Ichihara Eiki Harada Daijiro Kuyama Shoichi Inoue Koji Gemba Kenichi Ichikawa Hirohisa Kato Yuka Oda Naohiro Oze Isao Tamura Tomoki Kozuki Toshiyuki Umeno Takahiro Kubo Toshio Hotta Katsuyuki Bessho Akihiro Maeda Yoshinobu Kiura Katsuyuki 《International journal of clinical oncology / Japan Society of Clinical Oncology》2022,27(7):1139-1144
International Journal of Clinical Oncology - The role of pembrolizumab in the treatment of poor performance status (PS) patients remains unclear. We conducted a phase II trial to investigate the... 相似文献
8.
9.
Kenji Takagishi Tetsuya Matsuura Takashi Masatomi Etsuo Chosa Tsuyoshi Tajika Tetsu Iwama Mikihiko Watanabe Toshiro Otani Katsunori Inagaki Hiroyasu Ikegami Mitsuhiro Aoki Toru Okuwaki Yasushi Kameyama Maeda Akira Koji Kaneoka Masaaki Sakamoto Moroe Beppu 《Journal of orthopaedic science》2019,24(4):708-714
BackgroundDespite proposals and guidelines to prevent baseball injuries in young players by societies and organizations, many shoulder and elbow injuries continue to occur among junior high school baseball players. In order to investigate the training conditions of junior high school baseball players and the risk factors for shoulder and elbow pain in the players, we conducted a questionnaire survey among junior high school baseball players throughout the country.MethodsThe questionnaire survey was conducted among junior high school baseball players in September 2016.ResultsA total of 11,134 junior high school baseball players belonging to 495 teams responded to the survey. Among these, 4004 players trained every day of the week and 1151 players played baseball games every month with no off-season. Among 9752 players who did not have shoulder and/or elbow pain in the spring and summer of 2015, 19.2% of players experienced elbow pain over the course of one year, 13.6% of players experienced shoulder pain, and 28.0% complained of shoulder and/or elbow pain. The frequency of elbow pain was more than that of shoulder pain. At risk for shoulder pain were pitchers and catchers and second-year students, while risk factors for elbow pain were playing pitcher and catcher positions, pitching or throwing ≥300 balls per week, playing ≥10 games on average per month and being left-handed.ConclusionRisk factors for shoulder pain were different from those for elbow pain. To prevent elbow pain, coaches should pay attention to pitchers and catchers and left-handed players and not allow players to pitch or throw ≥300 full-power balls per week or participate in ≥10 games per month. They should also pay attention to pitchers and catchers and second-year students to prevent shoulder pain. It is important for coaches to train multiple pitchers and catchers. 相似文献
10.
Hiroto Tokumoto Takao Setoguchi Yoshinobu Saitoh Hiromi Sasaki Satoshi Nagano Shingo Maeda Akihide Tanimoto Noboru Taniguchi 《Molecular carcinogenesis》2019,58(12):2230-2240
Undifferentiated pleomorphic sarcoma (UPS) is the second most common soft tissue sarcoma. For patients with unresectable or metastatic disease, chemotherapies are considered, but in many cases they are not curative. There is a need to identify specific molecular dysregulations that can be therapeutic targets. We focused on neurotensin receptor 1 (NTSR1), which belongs to the G‐protein‐coupled receptor. NTSR1 expression was upregulated in specimens from patients with UPS. Real‐time polymerase chain reaction showed that expression of NTSR1 messenger RNA was 5‐ to 7‐fold increased in UPS cells compared with myoblasts. Western blot showed a high expression of NTSR1 protein in UPS cell lines. Knockdown of NTSR1 prevented UPS cell proliferation and invasion. We confirmed that SR48692, an inhibitor of NTSR1, exhibited antitumor activities in UPS cells. The combination index showed that SR48692 and standard chemotherapeutic drugs prevented UPS cell proliferation synergistically. Mouse xenograft models showed that SR48692 inhibited extracellular signal‐regulated kinase phosphorylation and enhanced the response to standard chemotherapeutic drugs. Inhibition of NTSR1 improved the effect of standard chemotherapeutic drugs for UPS. SR48692 may be a new drug for targeted UPS therapy. 相似文献