全文获取类型
收费全文 | 28957篇 |
免费 | 1460篇 |
国内免费 | 188篇 |
专业分类
耳鼻咽喉 | 245篇 |
儿科学 | 459篇 |
妇产科学 | 465篇 |
基础医学 | 3678篇 |
口腔科学 | 623篇 |
临床医学 | 1903篇 |
内科学 | 7635篇 |
皮肤病学 | 450篇 |
神经病学 | 2276篇 |
特种医学 | 1072篇 |
外科学 | 4973篇 |
综合类 | 149篇 |
一般理论 | 1篇 |
预防医学 | 789篇 |
眼科学 | 655篇 |
药学 | 2120篇 |
中国医学 | 97篇 |
肿瘤学 | 3015篇 |
出版年
2023年 | 185篇 |
2022年 | 360篇 |
2021年 | 588篇 |
2020年 | 389篇 |
2019年 | 476篇 |
2018年 | 624篇 |
2017年 | 422篇 |
2016年 | 605篇 |
2015年 | 618篇 |
2014年 | 793篇 |
2013年 | 955篇 |
2012年 | 1617篇 |
2011年 | 1683篇 |
2010年 | 914篇 |
2009年 | 747篇 |
2008年 | 1415篇 |
2007年 | 1500篇 |
2006年 | 1365篇 |
2005年 | 1431篇 |
2004年 | 1449篇 |
2003年 | 1278篇 |
2002年 | 1351篇 |
2001年 | 884篇 |
2000年 | 893篇 |
1999年 | 829篇 |
1998年 | 354篇 |
1997年 | 285篇 |
1996年 | 235篇 |
1995年 | 217篇 |
1994年 | 221篇 |
1993年 | 183篇 |
1992年 | 566篇 |
1991年 | 490篇 |
1990年 | 485篇 |
1989年 | 489篇 |
1988年 | 445篇 |
1987年 | 375篇 |
1986年 | 366篇 |
1985年 | 368篇 |
1984年 | 267篇 |
1983年 | 202篇 |
1982年 | 90篇 |
1979年 | 172篇 |
1978年 | 126篇 |
1977年 | 125篇 |
1974年 | 92篇 |
1972年 | 89篇 |
1971年 | 95篇 |
1968年 | 95篇 |
1967年 | 90篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
22.
Yuko Kamio Yurika Saito Naoki Utoguchi Masuo Kondoh Naoya Koizumi Makiko Fujii Yoshiteru Watanabe 《Journal of controlled release》2005,102(3):563-568
Some physiological substances, including acetylcholine and nitric oxide, are useful candidates for stimulation of intestinal absorption of drugs. In the present study, we elucidated the ability of epinephrine (Epi) to stimulate the intestinal absorption of drugs. We evaluated the ability of Epi to enhance absorption of macromolecules using dextran (Mw 4000 Da), which is poorly absorbed from the intestine, as a model compound in situ in a closed loop of the rat jejunum. Treatment of the jejunum with Epi resulted in significant increase in absorption of dextran in a dose-dependent fashion. The area under the curve (AUC) from 0 to 4 h in the Epi-treated jejunum was 13-fold higher than that in the vehicle-treated jejunum. The absorption-enhancing activity of Epi was 40-fold higher than that of caprate, a clinically used absorption-enhancer of drugs. In the experimental conditions used in this study, histological injury of the mucosa and perturbation of the mucosal membrane were not observed in the Epi-treated jejunum. Treatment with an antagonist of alpha-adrenergic receptors attenuated the stimulation of intestinal absorption by Epi, and treatment with an agonist of alpha-adrenergic receptors resulted in enhancement of intestinal absorption. While an antagonist of beta-adrenergic receptors enhanced the absorption-enhancing effect of Epi, an agonist of beta-adrenergic receptors stimulated intestinal absorption. These results indicate that stimulation of adrenergic receptors may be a novel strategy for intestinal absorption of drugs. 相似文献
23.
Yoshinori Igarashi Naoki Okano Ken Ito Takahiko Mimura Kazumasa Miki 《Digestive endoscopy》2007,19(Z1):S109-S114
A 69‐year‐old man was admitted to Toho University Omori Medical Center complaining of icterus. Abdominal computed tomography, magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography were suspicious of cholangioma of inferior bile duct. Peroral cholangioscopy using narrow band imaging (NBI) was performed and it was possible to diagnose the mucosal spread lesions of cholangioma. Histological findings reflected the endoscopic findings. Mucosal spread lesions of cholangiocarcinoma were successfully diagnosed using the CHF‐B260 for NBI. 相似文献
24.
Soichiro Yoshida Tetsuo Hayashi Makoto Morozumi Hisato Osada Norinari Honda Takumi Yamada 《International journal of urology》2007,14(7):665-667
The incidence of stonestreet formation after extracorporeal shock wave lithotripsy (ESWL) rises with increasing stone burden. However, stonestreet after ESWL is often experienced even in stones smaller than 20 mm. To examine whether the non-contrast helical computed tomography (CT) data could predict stonestreet formation in these stones, 53 radiopaque stones of 5-20 mm treated with ESWL were evaluated. Maximal dimension was measured on plain radiograph. From an attenuation value histogram graphed from the CT data, total stone volume and mean attenuation value were calculated. Seven stonestreets longer than 25 mm developed. There was no significant difference in maximal dimension and total stone volume between stones that did and stones that did not develop stonestreet. Mean attenuation value was the sole significant predictive factor. Application of mean attenuation value with cut-off level of 650 HU would anticipate stonestreet formation with a sensitivity of 85.7% and a specificity of 71.7%. The estimated risk of stonestreet formation is high in the treatment of stones with higher mean attenuation value. 相似文献
25.
Yuji Takeda Naoki Minato Yuji Katayama Tomoki Shimokawa 《General thoracic and cardiovascular surgery》2005,53(1):42-45
Two successful cases of the surgical treatment for coronary artery aneurysm (non-Kawasaki disease) were reported. The first
case had a saccular aneurysm on the left circumflex coronary artery (LCx) #14. Resection of the LCx aneurysm was performed
subsequent to single vessel coronary artery bypass grafting (CABG) to the distal portion of LCx#14 under the cardioplegic
cardiac arrest. The second case had aneurysms on both the left anterior descending artery (LAD) #7 (fusiform) and the LCx#11
(saccular). After double vessel CABG to LAD#7 and LCx#11, ligation or resection of two aneurysms was performed successfully.
Postoperative courses have been uneventful with good angiographic results achieved. Since these surgical procedures demonstrated
safety, the patients are expected to achieve a good long-term prognosis. 相似文献
26.
Sho Takahashi Hisato Homma Takehide Akiyama Shinichi Mesawa Kenichiro Hirata Katsuhisa Kogawa Kunihiro Takanashi Hirotoshi Ishiwatari Yutaka Kawano Tsuyoshi Hayashi Kohichi Takada Koji Miyanishi Junji Kato Yoshiro Niitsu 《Nihon Shokakibyo Gakkai zasshi》2007,104(8):1236-1244
A 75-year-old man had been admitted to another hospital because of left abdominal pain, and was given a diagnosis of left hydronephrosis and acute pancreatitis. After a JJ stent insertion and medication, he was transferred to our hospital for further examinations. US and EUS revealed a chronic pancreatitis-like pattern and multicystic lesion in the pancreas head and body. At that time enhanced CT findings showed an extrapancreatic low density area to be inflammatory change, extending from the pancreas body to the left crus of the diaphragm and posteriorly the spreading from the left crus of the diaphragm via the left urinary duct into the left iliopsoas muscle, in which MRI revealed partial high intensity. ERCP and MRCP showed focal irregular narrowing of the pancreatic duct of unknown cause, and we decided that an internal pancreatic fistula due to pancreatitis had induced left ureteral obstruction, caused by a protein plug or alcohol. Follow-up 6 months later showed that extrapancreatic spreading of the low density area had markedly regressed without any change in the ureteral obstruction. 相似文献
27.
Yoshinori Itoh Yutaka Kohgo Naoki Watanabe Yuji Kanisawa Sumio Sakamaki Minoru Takahashi Yasuo Hirayama Hiroyuki Ono Takeshi Himeno Yoshiro Niitsu 《Cancer science》1991,82(11):1203-1206
Human tumor–infiltrating lymphocytes (TILs) derived from pleural or ascitic fluid were incubated with recombinant interleukin 2 and transfected with human tumor necrosis factor (TNF) a gene by the lipofection procedure. The resulting TILs secreted significant amounts of TNF in the culture supernatant and exhibited cytotoxicity against established cell lines, such as K562 and Daudi, and autologous tumor cells. The TNF gene–transfected TILs exhibited an augmented killing of autologous tumor cells. 相似文献
28.
29.
Roberto Civitelli M.D. Eturo Ogata Louis V. Avioli Gary Stein Samuel Edelstein John A. Eisman Yasuho Nishii Hajime Orimo Jane Lian Takuo Fujita Yasufumi Hayashi Shigeaki Kato Tadashi Kobayashi Hirotoshi Morii Rikushi Morita Toshitaka Nakamura Yoshiki Seino Masataka Shiraki Tatsuo Suda Naoyuki Takahashi Hideaki Takahashi Tastuhiko Tanisawa Akifumi Tokita 《Calcified tissue international》1995,57(6):409-414
30.
Pituitary stalk meningioma: case report 总被引:1,自引:0,他引:1
We report a 45-year-old woman with a meningioma which was in contact with only the pituitary stalk on MRI. As the pituitary
stalk has no dura mater, we suggest this tumour may have originated from the arachnoid membrane of the pituitary stalk. Though
some reports have shown that meningiomas can arise from sites lacking a dural component, this is the first report of a meningioma
originating from the pituitary stalk.
Received: 21 December 1995 Accepted: 26 February 1996 相似文献