全文获取类型
收费全文 | 6613篇 |
免费 | 380篇 |
国内免费 | 38篇 |
专业分类
耳鼻咽喉 | 183篇 |
儿科学 | 196篇 |
妇产科学 | 156篇 |
基础医学 | 900篇 |
口腔科学 | 233篇 |
临床医学 | 548篇 |
内科学 | 1681篇 |
皮肤病学 | 254篇 |
神经病学 | 451篇 |
特种医学 | 199篇 |
外科学 | 677篇 |
综合类 | 22篇 |
一般理论 | 3篇 |
预防医学 | 274篇 |
眼科学 | 115篇 |
药学 | 569篇 |
中国医学 | 18篇 |
肿瘤学 | 552篇 |
出版年
2023年 | 51篇 |
2022年 | 67篇 |
2021年 | 159篇 |
2020年 | 93篇 |
2019年 | 125篇 |
2018年 | 138篇 |
2017年 | 130篇 |
2016年 | 144篇 |
2015年 | 144篇 |
2014年 | 192篇 |
2013年 | 235篇 |
2012年 | 394篇 |
2011年 | 379篇 |
2010年 | 222篇 |
2009年 | 217篇 |
2008年 | 359篇 |
2007年 | 344篇 |
2006年 | 324篇 |
2005年 | 311篇 |
2004年 | 316篇 |
2003年 | 308篇 |
2002年 | 285篇 |
2001年 | 181篇 |
2000年 | 185篇 |
1999年 | 178篇 |
1998年 | 57篇 |
1997年 | 55篇 |
1996年 | 54篇 |
1995年 | 49篇 |
1994年 | 41篇 |
1993年 | 35篇 |
1992年 | 107篇 |
1991年 | 89篇 |
1990年 | 89篇 |
1989年 | 109篇 |
1988年 | 96篇 |
1987年 | 106篇 |
1986年 | 95篇 |
1985年 | 75篇 |
1984年 | 59篇 |
1983年 | 44篇 |
1979年 | 50篇 |
1978年 | 26篇 |
1977年 | 27篇 |
1975年 | 21篇 |
1974年 | 30篇 |
1972年 | 20篇 |
1970年 | 19篇 |
1968年 | 21篇 |
1966年 | 26篇 |
排序方式: 共有7031条查询结果,搜索用时 9 毫秒
81.
82.
83.
Koichiro Ota Taiki Watanabe Shuntaro Igarashi Shinnosuke Okazaki Kazuo Kamaike Hiroaki Miyaoka 《RSC advances》2022,12(26):16576
This study reports the stereoselective total syntheses of the antipodes of the unique 3/10 bicyclic skeletal sesquiterpenoids, namely, hypocoprin A and hypocoprin B. The synthesis involved conjugate addition accelerated by trimethylsilyl chloride, construction of the ten-membered ring via the intramolecular SN2 reaction promoted by 1,8-diazabicyclo[5.4.0]undec-7-ene, and osmium-mediated π-facial selective dihydroxylation to functionalize the 1,1-disubstituted alkene.This study reports the stereoselective total syntheses of the antipodes of the unique 3/10 bicyclic skeletal sesquiterpenoids, namely, hypocoprin A and hypocoprin B. 相似文献
84.
Intraductal papillary mucinous tumor of the pancreas associated with autosomal dominant polycystic kidney disease 总被引:1,自引:0,他引:1
Hiroshi Naitoh M.D. Hisanori Shoji M.D. Isao Ishikawa M.D. Reina Watanabe M.D. Yuichi Furuta M.D. Shigeru Tomozawa M.D. Hiroaki Igarashi M.D. Sachiko Shinozaki M.D. Hideyuki Katsura M.D. Ryoichi Onozato M.D. Masayoshi Kudoh M.D. 《Journal of gastrointestinal surgery》2005,9(6):843-845
A 43-year-old male with a history of autosomal dominant polycystic kidney disease (ADPKD) was admitted to our center with severe abdominal pain and was diagnosed with acute pancreatitis. CT showed multiple cysts in the liver and both kidneys along with ADPKD and a cystic mass, 4 cm in diameter, in the pancreatic head. The main pancreatic duct was dilated to 1 cm in diameter. The patient was diagnosed with acute pancreatitis due to intraductal papillary mucinous tumor (IPMT), and pancreatoduodenectomy was performed. Histologic examination revealed a multiloculated cystic tumor filled with mucin in the head of the pancreas. Microscopically, the tumor was diagnosed as adenocarcinoma and was found to have invaded the main pancreatic duct. Although, in addition to our case, only seven cases with association between ADPKD and malignant neoplasms have been reported, five of these cases had neoplasms arising from the pancreas. Therefore, we suggest that some genetic interactions may exist between ADPKD and pancreatic carcinogenesis. 相似文献
85.
Nobuyuki Nishikawa Rie Yago Yuichiro Yamazaki Hiromitsu Negoro Mari Suzuki Masaaki Imamura Yoshinobu Toda Kazunari Tanabe Osamu Ogawa Akihiro Kanematsu 《BMC urology》2015,15(1)
Background
To investigate the expression of parathyroid hormone (PTH)/PTH-related peptide (PTHrP) receptor 1 (PTH1R) in clinical specimens of normal and diseased bladders. PTHrP is a unique stretch-induced endogenous detrusor relaxant that functions via PTH1R. We hypothesized that suppression of this axis could be involved in the pathogenesis of bladder disease.Methods
PTH1R expression in clinical samples was examined by immunohistochemistry. Normal kidney tissue from a patient with renal cancer and bladder specimens from patients undergoing ureteral reimplantation for vesicoureteral reflux or partial cystectomy for urachal cyst were examined as normal control organs. These were compared with 13 diseased bladder specimens from patients undergoing bladder augmentation. The augmentation patients ranged from 8 to 31 years old (median 15 years), including 9 males and 4 females. Seven patients had spinal disorders, 3 had posterior urethral valves and 3 non-neurogenic neurogenic bladders (Hinman syndrome).Results
Renal tubules, detrusor muscle and blood vessels in normal control bladders stained positive for PTH1R. According to preoperative urodynamic studies of augmentation patients, the median percent bladder capacity compared with the age-standard was 43.6% (range 1.5–86.6%), median intravesical pressure at maximal capacity was 30 cmH2O (range 10–107 cmH2O), and median compliance was 3.93 ml/cmH2O (range 0.05–30.3 ml/cmH2O). Detrusor overactivity was observed in five cases (38.5%). All augmented bladders showed negative stainings in PTH1R expression in the detrusor tissue, but positive staining of blood vessels in majority of the cases.Conclusions
Downregulation of PTH1R may be involved in the pathogenesis of human end-stage bladder disease requiring augmentation. 相似文献86.
Chiyohiko Shindoh Rie Shishido Katsuyuki Sasaki Masahito Miura 《Allergology international》2011,60(3):365-372
BackgroundAlthough oxitropium bromide is used clinically as an anticholinergic drug (i.e., parasympathetic antagonist) to relax airway smooth muscle, we examined whether it has or does not have any effects on diaphragm muscle.MethodsThree treatment sets, an oxitropium bromide inhalation only group, an oxitropium bromide inhalation plus endotoxin injection group (in vivo) and an oxitropium bromide incubation group (in vitro) were studied as to diaphragm muscle contractile properties.ResultsOxitropium bromide inhalation shifted force-frequency curves upward at 2 h after inhalation (p < 0.05) and inhibited the decrease of force-frequency curves due to endotoxin injection in vivo. Incubation with oxitropium bromide of untreated diaphragm muscle and diaphragm muscle injected with endotoxin did not increase the force-frequency curves dose-dependently in vitro; however, it caused both types of muscle to be fatigue resistant.ConclusionsWe speculate that the increment of muscle contractility with the inhalation of oxitropium bromide was induced by the antagonization of musucarinic acetylcholine receptors (mAChR). In addition, the changes of fatigue resistance provoked by oxitropium bromide, which also is speculated to antagonize mAChR, may be beneficial in the treatment of patients with COPD. 相似文献
87.
Rie Fukui Eriko Tanabe Misaho Kitayoshi Kyohei Yoshikawa Nobuyuki Fukushima Toshifumi Tsujiuchi 《Tumour biology》2012,33(6):1899-1905
Lysophosphatidic acid (LPA) mediates a wide range of biological responses with G protein-coupled transmembrane receptors (LPA receptors). So far, at least six types of LPA receptors (LPA receptor-1 (LPA1) to LPA6) have been identified. Recently, it has been reported that LPA3 indicates opposite effects on cellular functions of cancer cells. In the present study, to assess a biological role of LPA3 on cell migration ability of colon cancer cells, we generated LPA receptor-3 (LPAR3) knockdown (HCT-sh3-3) cells from HCT116 and measured cell motile and invasion activities. In motility assay with a cell culture insert, HCT-sh3-3 cells showed significantly high cell motile activity, compared with control cells. For invasion assay, the filter was coated with Matrigel. The invasive activity of HCT-sh3-3 cells was significantly higher than that of control cells. Furthermore, we also examined the effects of LPAR3 knockdown on the interaction between colon cancer cells and endothelial F-2 cells. When F-2 cells were cultured with serum-free DMEM containing a supernatant from HCT-sh3-3 cells, the cell growth rate and migration activity of F-2 cells were significantly stimulated, associating with the elevated expressions of vascular endothelial growth factor (VEGF)-A and VEGF-C genes in HCT-sh3-3 cells. These results suggest that LPA3 may act as a negative regulator on cell motile and invasive abilities of colon cancer HCT116 cells. 相似文献
88.
Akiko Chino Teruhito Kishihara Naoyuki Uragami Akiyoshi Ishiyama Taishi Ogawa Etsuo Hoshino Masahiro Igarashi Rikiya Fujita 《Digestive endoscopy》2009,21(1):56-58
The present patient developed a severe rectal ulcer more than 1 month after having received external beam radiation therapy for prostate cancer. Surveillance endoscopy every 3 months demonstrated healing of this rectal ulcer using a novel therapy. He was given enemas with ecabet sodium, which provides physical protection and promotes healing by increasing prostaglandin E2, and this process induced squamous metaplasia that halted the progression of the ulcer of radiation proctitis as a late‐phase reaction. Intrapapillary capillary loops were visualized with magnified narrow band imaging at the healing ulcer site as seen via the esophagus and, moreover, demonstrated histologically. 相似文献
89.
90.