全文获取类型
收费全文 | 2496篇 |
免费 | 145篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 28篇 |
儿科学 | 92篇 |
妇产科学 | 49篇 |
基础医学 | 372篇 |
口腔科学 | 56篇 |
临床医学 | 177篇 |
内科学 | 532篇 |
皮肤病学 | 112篇 |
神经病学 | 311篇 |
特种医学 | 67篇 |
外科学 | 218篇 |
综合类 | 7篇 |
预防医学 | 103篇 |
眼科学 | 47篇 |
药学 | 250篇 |
中国医学 | 9篇 |
肿瘤学 | 221篇 |
出版年
2023年 | 22篇 |
2022年 | 42篇 |
2021年 | 59篇 |
2020年 | 40篇 |
2019年 | 65篇 |
2018年 | 73篇 |
2017年 | 57篇 |
2016年 | 62篇 |
2015年 | 59篇 |
2014年 | 93篇 |
2013年 | 113篇 |
2012年 | 180篇 |
2011年 | 210篇 |
2010年 | 120篇 |
2009年 | 114篇 |
2008年 | 172篇 |
2007年 | 183篇 |
2006年 | 155篇 |
2005年 | 171篇 |
2004年 | 138篇 |
2003年 | 120篇 |
2002年 | 123篇 |
2001年 | 26篇 |
2000年 | 20篇 |
1999年 | 20篇 |
1998年 | 16篇 |
1997年 | 12篇 |
1996年 | 16篇 |
1995年 | 8篇 |
1994年 | 8篇 |
1993年 | 9篇 |
1992年 | 12篇 |
1991年 | 13篇 |
1990年 | 15篇 |
1989年 | 13篇 |
1988年 | 12篇 |
1987年 | 8篇 |
1986年 | 6篇 |
1985年 | 10篇 |
1984年 | 5篇 |
1982年 | 5篇 |
1981年 | 5篇 |
1980年 | 7篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1977年 | 3篇 |
1974年 | 3篇 |
1973年 | 3篇 |
1970年 | 3篇 |
1967年 | 3篇 |
排序方式: 共有2651条查询结果,搜索用时 78 毫秒
21.
Haemodynamic effects of the crude venom from nematocysts of the box-jellyfish Chiropsalmus quadrigatus (Habu-kurage) in anaesthetized rabbits. 总被引:1,自引:0,他引:1
Tomoyuki Koyama Katsuhiko Noguchi Toshihiro Matsuzaki Mayuko Sakanashi Junko Nakasone Kanako Miyagi Makiko Sakanashi Matao Sakanashi 《Toxicon》2003,41(5):621-631
Haemodynamic effects of saline-extracted venom from nematocysts isolated from tentacles of the box-jellyfish Chiropsalmus quadrigatus (Habu-kurage) were investigated. In anaesthetized rabbits, i.v. injections of the venom produced hypotension following a transient hypertension. Mean femoral arterial blood flow markedly decreased immediately after the injection and femoral vascular resistance increased. Left ventricular dP/dt remarkably decreased after a transient and small increase, and heart rate decreased. Left ventricular end-diastolic pressure markedly elevated. All of the above changes by 0.2-5 microg/kg of the venom expressed as the amount of protein were seen dose-dependently and occurred without tachyphylaxis. In five of seven animals received an injection of the venom at 10 microg/kg, irreversible cardiac arrest occurred. Changes produced by 1 or 2 microg/kg of the venom were significantly attenuated either by heating the venom at 40 degrees C for 10min or by pretreatment with diltiazem. These results indicate that the venom from Habu-kurage has both vasoconstrictor and cardiodepressive effects, and suggest that these thermolabile actions may be due partly to activation of voltage-dependent calcium channels and probably subsequent calcium-overload. 相似文献
22.
Yoshika Nagata Takeshi Hanagiri Mitsuhiro Takenoyama Takashi Fukuyama Makiko Mizukami Tetsuya So Yoshinobu Ichiki Masakazu Sugaya Kenji Sugio Kosei Yasumoto 《Clinical cancer research》2005,11(14):5265-5272
PURPOSE: A large number of tumor-associated antigens have been used in vaccination trials for mainly melanomas. Our purpose of this study is to identify a novel tumor antigen useful for immunotherapy of lung cancer patients. EXPERIMENTAL DESIGN: Analysis of an autologous tumor-specific CTL clone F2a that was established from regional lymph node lymphocytes of a patient with lung cancer (A904) by a mixed lymphocyte-tumor cell culture. RESULTS: F2a recognized and killed autologous tumor cells (A904L), whereas it did not respond to autologous EBV-transformed B cells, phytohemagglutinin-blastoid T cells, and K562 cells. cDNA clone 31.2 was isolated by using cDNA expression cloning method as a gene encoding antigen. This gene was identical to the reported gene whose function was unknown. The antigen encoded by the cDNA was recognized by the CTL in a HLA-Cw*0702-restricted manner. Furthermore, a 9-mer peptide at positions 659 to 685 in cDNA clone 31.2 was identified as a novel epitope peptide. The CTL recognized some allogeneic cancer cell lines with HLA-Cw*0702 as well as some HLA-Cw*0702-negative cell lines when transfected with HLA-Cw*0702, thus indicating that the identified antigen was a cross-reactive antigen. CONCLUSIONS: Although exact mechanism to process the encoded protein and present the antigen in the context of HLA class I remains to be elucidated, the CTL recognized some of tumor cells in the context of HLA-Cw*0702 but did not recognize a variety of normal cells and also autologous EBV-transformed B cells. These results indicated that the antigen identified in this study may therefore be a possible target of tumor-specific immunotherapy for lung cancer patients. 相似文献
23.
Atsuko Koizumi Makiko Fujii Masuo Kondoh Yoshiteru Watanabe 《European journal of pharmaceutics and biopharmaceutics》2004,57(3):473-478
N-Methyl-2-pyrrolidone (NMP) increased the skin permeation of estradiol (E2) in Yucatan micropig epidermis using a modified Franz-type diffusion cell. The addition of NMP significantly increased the fluxes of E2 from water and soybean oil. The flux and skin concentration of E2 were higher from soybean oil than from water and increased with increasing NMP concentrations in soybean oil. Correlation was observed with E2 flux and skin concentration (R(2) = 0.804) NMP enhanced E2 skin permeation because NMP made E2 skin concentration higher. Thus, NMP (10%) was added to the oily gel made by isocetyl isostearate and hydrogenated phospholipid. E2 permeation from the gel without NMP was the same as that from soybean oil suspension. The flux of E2 from the gel with NMP was 0.6 microg/h per cm(2) and might be sufficient for estrogen replacement therapy. 相似文献
24.
25.
26.
Aim: To assess the physical and mental burdens associated with expressing empathy with another person's stress. Methods: Nine female subjects listened to their partner's negative emotions aroused by a stress task (Stroop color‐word test) under two conditions. In the first, the subject reacted empathetically to their partner (“with empathy”); in the second, the subject offered no response (control). Electroencephalograms and skin temperature of the second finger were recorded during the test. Subjective stress was estimated using a visual analog scale, whereas the level of cognition was expressed on a five‐point ranking. Responses during and after expressions of empathy were examined by comparisons with control or by correlation. Results: Sympathetic nerve tone increased under both conditions (i.e. the skin temperature of the second finger fell). Subjective stress was not recognized by the subject while listening “with empathy”, although it did increase significantly after the subject has listened “with empathy”. Subjective stress was not felt under the control conditions. Right temporal activity while listening showed a significantly positive correlation with the level of cognition of feeling the same emotion as the stressed partner, whereas bilateral frontal activity after listening was significantly negative correlated with the level of cognition of understanding the emotions of the stressed partner. Conclusion: Expressing empathy with another person's negative emotion led to increased physiological activity and subjective stress. Physiological responses to empathy depended on cognition of the different subjective factors. Cognition of sharing negative emotions activated the right temporal region of the brain, whereas cognition of understanding negative emotions inhibited bilateral frontal activities. 相似文献
27.
28.
29.
Kazutaka Doi Makiko N. Mieno Yoshiya Shimada Hidenori Yonehara Shinji Yoshinaga 《Journal of radiation research》2014,55(5):885-901
Although radiotherapy is recognized as an established risk factor for second malignant neoplasms (SMNs), the dose response of SMNs following radiotherapy has not been well characterized. In our previous meta-analysis of the risks of SMNs occurring among children who have received radiotherapy, the small number of eligible studies precluded a detailed evaluation. Therefore, to increase the number of eligible studies, we developed a method of calculating excess relative risk (ERR) per Gy estimates from studies for which the relative risk estimates for several dose categories were available. Comparing the calculated ERR with that described in several original papers validated the proposed method. This enabled us to increase the number of studies, which we used to conduct a meta-analysis. The overall ERR per Gy estimate of radiotherapy over 26 relevant studies was 0.60 (95%CI: 0.30–1.20), which is smaller than the corresponding estimate for atomic bomb survivors exposed to radiation as young children (1.7; 95% CI: 1.1–2.5). A significant decrease in ERR per Gy with increase in age at exposure (0.85 times per annual increase) was observed in the meta-regression. Heterogeneity was suggested by Cochran''s Q statistic (P < 0.001), which may be partly accounted for by age at exposure. 相似文献
30.
Yasuhiro Kuraishi Takashi Muraki Norihiro Ashihara Makiko Ozawa Akira Nakamura 《Scandinavian journal of gastroenterology》2013,48(6):773-779
AbstractObjectives: Autoimmune pancreatitis (AIP) sometimes becomes complicated with pancreatic cysts, although their detailed characteristics and management strategy have not been fully determined. We aimed to clarify the efficiency of steroid therapy and the risk factors for cyst formation and cyst-related complications.Methods: One hundred sixty-three AIP patients were retrospectively analyzed for relevant factors of cyst formation. We compared subjects with and without steroids to evaluate drug effectiveness on cyst size change and investigated the factors associated with cyst-related complications.Results: Thirty-two patients (19.6%) had complicating pancreatic cyst formation, and 40 cystic lesions of ≥10?mm in size were detected. Multivariate analysis revealed a drinking habit, abdominal/back pain, and elevated serum amylase to be significantly associated with cyst formation. Steroid-treated cysts became significantly reduced in size in the short-term and disappeared significantly more frequently within 1-year as compared with non-treated ones, which was confirmed by multivariate analysis. Six of 40 cysts exhibited cyst-related complications significantly associated with multilocular morphology and larger size.Conclusions: Steroid therapy is an effective choice for cysts developing in AIP to promote the release of pancreatic juice stasis. Larger lesions with multilocular morphology should be monitored closely for cyst-related complications and be considered strong candidates for steroid therapy. 相似文献