全文获取类型
收费全文 | 2061篇 |
免费 | 80篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 28篇 |
儿科学 | 77篇 |
妇产科学 | 23篇 |
基础医学 | 294篇 |
口腔科学 | 74篇 |
临床医学 | 145篇 |
内科学 | 408篇 |
皮肤病学 | 12篇 |
神经病学 | 130篇 |
特种医学 | 76篇 |
外科学 | 307篇 |
综合类 | 11篇 |
预防医学 | 71篇 |
眼科学 | 22篇 |
药学 | 270篇 |
中国医学 | 12篇 |
肿瘤学 | 190篇 |
出版年
2022年 | 14篇 |
2021年 | 19篇 |
2020年 | 12篇 |
2019年 | 6篇 |
2018年 | 19篇 |
2017年 | 17篇 |
2016年 | 17篇 |
2015年 | 24篇 |
2014年 | 26篇 |
2013年 | 43篇 |
2012年 | 149篇 |
2011年 | 146篇 |
2010年 | 55篇 |
2009年 | 42篇 |
2008年 | 141篇 |
2007年 | 144篇 |
2006年 | 142篇 |
2005年 | 157篇 |
2004年 | 145篇 |
2003年 | 131篇 |
2002年 | 135篇 |
2001年 | 46篇 |
2000年 | 50篇 |
1999年 | 58篇 |
1998年 | 21篇 |
1997年 | 21篇 |
1996年 | 16篇 |
1995年 | 23篇 |
1994年 | 13篇 |
1993年 | 9篇 |
1992年 | 33篇 |
1991年 | 26篇 |
1990年 | 16篇 |
1989年 | 18篇 |
1988年 | 30篇 |
1987年 | 22篇 |
1986年 | 19篇 |
1985年 | 10篇 |
1984年 | 9篇 |
1983年 | 18篇 |
1982年 | 6篇 |
1981年 | 10篇 |
1980年 | 9篇 |
1979年 | 15篇 |
1978年 | 11篇 |
1977年 | 9篇 |
1976年 | 10篇 |
1975年 | 6篇 |
1974年 | 5篇 |
1972年 | 5篇 |
排序方式: 共有2150条查询结果,搜索用时 15 毫秒
31.
32.
33.
Yasuhiko Kano Miyuki Akutsu Saburo Tsunoda Koyoshi Mori Kenichi Suzuki Ken-Ichi Adachi 《Cancer chemotherapy and pharmacology》1998,42(2):91-98
Paclitaxel and irinotecan are important new anticancer agents. The combination of these two agents has been considered for
use against a variety of advanced solid tumors. Since the schedule-dependent effects of this combination may be crucial to
its use, we studied the interaction of paclitaxel and SN-38 (the active metabolite of irinotecan) in various schedules in
four human cancer cell lines in culture. Cell growth inhibition after 5 days was determined using an MTT assay. The effects
of drug combinations at the IC80 level were analyzed by the isobologram method. Simultaneous exposure to paclitaxel and SN-38 for 24 h produced antagonistic
(subadditive and protective) effects in the human lung cancer cell line A549, the breast cancer cell line MCF7, and the colon
cancer cell line WiDr, and produced additive effects in the ovarian cancer cell line PA1. Sequential exposure to paclitaxel
for 24 h followed by SN-38 for 24 h, and the reverse sequence, produced additive effects in all four cell lines. These findings
suggest that sequential administration, not simultaneous administration, may be the appropriate schedule for the therapeutic
combination of paclitaxel and irinotecan. Continued preclinical and clinical studies should provide further insights and assist
in determining the optimal schedule for this combination in clinical use.
Received: 25 February 1997 / Accepted: 6 November 1997 相似文献
34.
Noriko Hosoya Kiyoshi Miyagawa Kinuko Mitani Yoshio Yazaki Hisamaru Hirai 《Cancer science》1998,89(8):821-824
The WT1 tumor suppressor gene was examined for mutations in a panel of 44 patients with myelo-dysplastic syndromes (MDS) including acute myelogenous leukemias (AML) secondary to MDS, using polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) analysis and sequencing analysis. A WT1 mutation was detected in one out of 17 cases of AML secondary to MDS. This mutation exists upstream of the zinc finger region and is predicted to produce a truncated WT1 protein lacking the zinc finger region. No mutations were detected in 27 MDS patients who had not progressed to AML. This is the first report of analysis for WT1 mutations in a large number of MDS patients, suggesting that WT1 mutations are uncommon in MDS. Abnormalities in this gene may, however, contribute to a small proportion of cases showing progression from MDS into AML. 相似文献
35.
M Hosoya Y Kawasaki M Katayose H Sakuma M Watanabe E Igarashi M Aoyama H Nunoi H Suzuki 《Archives of disease in childhood》2006,91(6):469-472
AIMS: To evaluate the prognostic predictive values of cytochrome c, cytokines, and other laboratory measurements in serum collected during neurological onset in acute encephalopathy with multiple organ failure. METHODS: In addition to general laboratory examinations, the concentrations of cytochrome c (apoptosis marker) and cytokines (inflammatory markers) were measured in serum samples collected at the initial phase in 29 patients with acute encephalopathy. The obtained values were evaluated as predictors for the development of severe encephalopathy. RESULTS: Cytochrome c, tumour necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6), soluble TNF-receptor 1 (sTNF-R1), and aspartate aminotransferase (AST) concentrations at the initial phase were high and correlated well with patient outcome. High concentrations of serum cytochrome c (>45 ng/ml), sTNF-R1 (>2000 pg/ml), AST (>58 IU/dl), IL-6 (>60 pg/ml), and TNF-alpha (>15 pg/ml) predicted an unfavourable prognosis (sequelae and death) at 93%, 79%, 82%, 77%, and 60%, respectively. The specificity of those markers was 100%, 89%, 83%, 100%, and 100%, respectively. CONCLUSIONS: Serum cytochrome c is the most sensitive and specific predictor for the development of severe encephalopathy at the initial phase. Results suggest that this marker might be used to guide decisions regarding the start of the initial treatment and further intensive care. 相似文献
36.
A new simply and effective fractionation method for cylindrospermopsin (CYN) analyses was developed. The extract from cells of Cylindrospermopsis raciborskii was resuspended with 0.1 M carbonate buffer at pH 10.5, and pass through the double-cartridges column which was consisted of a styrene polymer cartridge and an anion exchange cartridge. CYN and deoxy-CYN were adsorbed with the anion exchange cartridge. After separation of the anion exchange cartridge, adsorbed compounds were eluted from the cartridge with 50% methanol containing 1% formic acid solution. CYN and deoxy-CYN were selectively condensed in the eluted solution. When CYN was analyzed by LC-photodiode array or LC/MS, only two peaks of CYN and deoxy-CYN were detected quantitatively. The results suggest that the fractionation method is a useful method for CYN analyses and must be utilized for CYN purification. 相似文献
37.
Hironobu Shibata Masahiro Abe Kenji Hiura Javier Wilde Keiji Moriyama Toshiaki Sano Ken-Ichi Kitazoe Toshihiro Hashimoto Shuji Ozaki Shingo Wakatsuki Shinsuke Kido Daisuke Inoue Toshio Matsumoto 《Clinical cancer research》2005,11(17):6109-6115
PURPOSE: Receptor activator of nuclear factor-kappaB ligand (RANKL) is a key mediator of osteoclastogenesis. Because certain types of tumor cells aberrantly express RANKL, and because bone destruction also develops in B-cell lymphomas of bone origin, we investigated RANKL expression and the mechanisms of osteoclastogenesis in B-lymphoid neoplasms. EXPERIMENTAL DESIGN AND RESULTS: Immunohistochemistry of bone specimens resected from patients with primary B-cell lymphoma of bone with bone destruction revealed that lymphoma cells express RANKL as well as vascular endothelial cell growth factor (VEGF). The tumor cells isolated from the bone specimens enhanced osteoclastogenesis in vitro. In contrast, B-cell lymphoma infiltrating to the bone marrow without bone destruction did not express RANKL. Both RANKL and VEGF were expressed by a portion of B-lymphoid cell lines, including Daudi and IM-9. These RANKL-expressing tumor cells enhanced osteoclastogenesis from RAW264.7 cells and human monocyte-derived preosteoclasts in the absence of stromal cells/osteoblasts in a RANKL-dependent manner. Furthermore, conditioned media from Daudi cells enhanced transmigration of preosteoclasts that was inhibited by anti-VEGF antibody, suggesting that tumor cell-derived VEGF mediates recruitment of osteoclast precursors. Moreover, cocultures of B-lymphoid cell lines with osteoclasts enhanced the growth of B-lymphoid cells. CONCLUSIONS: Some malignant B cells aberrantly express functional RANKL as well as VEGF to enhance osteoclastogenesis. The coexpression of RANKL and VEGF may also contribute to the close cellular interactions with osteoclastic cells, thereby forming a vicious cycle between osteoclastic bone destruction and tumor expansion in bone. 相似文献
38.
Isoo Noguchi Kazuyoshi Suzuki Takumasa Yoshida Yuko Yamamoto Miyako Ono Yasushi Yamazaki Kazuhito Satomura Takashi Ohyama Noriyasu Hosoya 《Journal of endodontics》2021,47(4):641-647
IntroductionThe purpose of this study was to assess the optimal amplitude and weight of the newly developed contra-angle handpiece. The handpiece uses piston movement without using an endodontic motor and enables a safe, quick, and reliable canal preparation.MethodsA prototype handpiece was designed. Instrumentation was performed on root canal resin blocks by 20 operators in 3 groups: the prototype handpiece with an H file (a stainless steel #25 manual H file, the piston group), a manually standardized technique with a K file (stainless steel #15–25 K files, the manual group), and a nickel-titanium (NiTi) reciprocating file with an endodontic motor (Reciproc Blue R25 [VDW, Munich, Germany], the NiTi group). Transportation of the canal center line and the time required for preparation were measured and statistically analyzed.ResultsThe optimal condition was an amplitude of 1.35 mm and a weight of 61.0 g. Transportation of the canal center was observed in all groups. A statistically significant difference was found at 2.0–3.0 mm from the apical foramen between the piston or NiTi group and the manual group, but no significant difference was found between the piston and NiTi groups. The least transportation was found in the NiTi and piston groups. The handpiece with a #25 H file demonstrated a good centering ability, similar to the NiTi file, which enabled speedy preparation. The time required for preparation between the piston or NiTi group and the manual group was statistically different. No significant difference was observed between the piston and NiTi groups (P < .05).ConclusionsWe concluded that the newly designed handpiece achieved efficient canal preparation and negotiation. The handpiece could avoid endodontic accidents, including ledge formation, instrument separation, and perforation. 相似文献
39.
40.