全文获取类型
收费全文 | 4028篇 |
免费 | 223篇 |
国内免费 | 48篇 |
专业分类
耳鼻咽喉 | 35篇 |
儿科学 | 79篇 |
妇产科学 | 52篇 |
基础医学 | 514篇 |
口腔科学 | 152篇 |
临床医学 | 237篇 |
内科学 | 964篇 |
皮肤病学 | 78篇 |
神经病学 | 333篇 |
特种医学 | 204篇 |
外科学 | 733篇 |
综合类 | 19篇 |
预防医学 | 93篇 |
眼科学 | 84篇 |
药学 | 251篇 |
中国医学 | 4篇 |
肿瘤学 | 467篇 |
出版年
2023年 | 42篇 |
2022年 | 81篇 |
2021年 | 147篇 |
2020年 | 83篇 |
2019年 | 88篇 |
2018年 | 108篇 |
2017年 | 104篇 |
2016年 | 96篇 |
2015年 | 112篇 |
2014年 | 129篇 |
2013年 | 167篇 |
2012年 | 230篇 |
2011年 | 226篇 |
2010年 | 120篇 |
2009年 | 114篇 |
2008年 | 170篇 |
2007年 | 238篇 |
2006年 | 204篇 |
2005年 | 199篇 |
2004年 | 169篇 |
2003年 | 143篇 |
2002年 | 147篇 |
2001年 | 97篇 |
2000年 | 83篇 |
1999年 | 74篇 |
1998年 | 47篇 |
1997年 | 37篇 |
1996年 | 41篇 |
1995年 | 32篇 |
1994年 | 24篇 |
1993年 | 27篇 |
1992年 | 59篇 |
1991年 | 54篇 |
1990年 | 37篇 |
1989年 | 57篇 |
1988年 | 60篇 |
1987年 | 75篇 |
1986年 | 54篇 |
1985年 | 37篇 |
1984年 | 34篇 |
1983年 | 42篇 |
1982年 | 18篇 |
1981年 | 17篇 |
1980年 | 22篇 |
1979年 | 27篇 |
1978年 | 14篇 |
1977年 | 12篇 |
1973年 | 14篇 |
1971年 | 13篇 |
1970年 | 15篇 |
排序方式: 共有4299条查询结果,搜索用时 15 毫秒
61.
Daisuke Miyaki Hiroshi Aikata Yohji Honda Noriaki Naeshiro Takashi Nakahara Mio Tanaka Yuko Nagaoki Tomokazu Kawaoka Shintaro Takaki Koji Waki Akira Hiramatsu Shoichi Takahashi Masaki Ishikawa Hideaki Kakizawa Kazuo Awai Kazuaki Chayama 《Journal of gastroenterology and hepatology》2012,27(12):1850-1857
62.
Makio Kusaoi Ken Yamaji Go Murayama Misa Yasui Risa Yamada Ruka Hishinuma Takuya Nemoto Katsura Hohtatsu Michiaki Kageyama Toshio Kawamoto Kaoru Sugimoto Fumio Sekiya Takayuki Kon Michihiro Ogasawara Kazuo Kempe Hiroshi Tsuda Yoshinari Takasaki 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2012,16(5):456-466
Leukocytapheresis (LCAP) is a safe, unique therapy pertaining to intractable rheumatoid arthritis (RA) even in cases of drug allergy or infectious states. To investigate how to represent LCAP efficacy, we have conducted gene expression analyses from the peripheral blood of RA patients treated with non‐woven polyethylene terephthalate filters. Peripheral blood samples were collected immediately before and after treatment from eight RA patients who received LCAP. Among these patients, all of them achieved 20% improvement in the core set of the American College of Rheumatology (ACR20), and thus, they were confirmed as LCAP responders. Gene expression analysis was done with a high‐resolution DNA microarray. The results of each of the two groups' gene expression values (immediately before and after LCAP) were calculated using Welch's t‐test. Calculations were performed with a statistical software R.basic package: if the P‐value was less than 0.05, this was seen as a significant change. In a comparison of 25 370 gene expressions, the number of genes showing a P‐value < 0.05 in the upregulating group was 2110, and in the downregulating group it was 1864. The results of pathway analysis using the MetaCore program indicate that gene groups work for cytoskeletal remodeling are upregulated, and genes related to immune responses, such as antigens presenting via major histocompatibility complex class I and II, are downregulated just after LCAP. These findings may relate to LCAP efficacy for RA patients, but this needs further investigation. 相似文献
63.
64.
65.
Shota Hodono Yukiko Yamauchi Ayano Kawamura Hironobu Matsumoto Shintaro Okumura Hideaki Fujiwara Atsuomi Kimura 《NMR in biomedicine》2016,29(10):1414-1419
The use of a quenching gas, isobutene, with a low vapor pressure was investigated to enhance the utility of hyperpolarized 129Xe (HP Xe) MRI. Xenon mixed with isobutene was hyperpolarized using a home‐built apparatus for continuously producing HP Xe. The isobutene was then readily liquefied and separated almost totally by continuous condensation at about 173 K, because the vapor pressure of isobutene (0.247 kPa) is much lower than that of Xe (157 kPa). Finally, the neat Xe gas was continuously delivered to mice by spontaneous inhalation. The HP Xe MRI was enhanced twofold in polarization level and threefold in signal intensity when isobutene was adopted as the quenching gas instead of N2. The usefulness of the HP Xe MRI was verified by application to pulmonary functional imaging of spontaneously breathing mice, where the parameters of fractional ventilation (ra) and gas exchange (fD) were evaluated, aiming at future extension to preclinical studies. This is the first application of isobutene as a quenching gas for HP Xe MRI. 相似文献
66.
67.
68.
Takaki S Tsubota A Hosaka T Akuta N Someya T Kobayashi M Suzuki F Suzuki Y Saitoh S Arase Y Ikeda K Kumada H 《Journal of gastroenterology》2004,39(7):668-673
Background Recent studies indicate that combination therapy with ribavirin and interferon alfa2b (IFN2b) is effective for chronic hepatitis C virus (HCV) infection. However, reversible hemolytic anemia is a common side effect of this therapy.Methods We determined those factors that contribute to ribavirin dose reduction due to anemia during this treatment by using multiple logistic regression analysis in Japanese patients. The study included 123 patients with chronic hepatitis C (85 male, 38 female; mean age, 50 years; range, 20–70 years), who received 24-week combination therapy. All patients were treated with IFN2b daily for 2 weeks, followed by three times weekly dosing for 22 weeks, with oral ribavirin twice daily, at a total daily dose of 600 or 800mg.Results Of the 123 patients, 34 patients required dose reduction of ribavirin, and 78 patients required no dose reduction. Overall, 20 patients discontinued. On univariate analysis, reduction of the ribavirin dose correlated significantly with pretreatment hemoglobin (Hb) levels of less than 14g/dl, female sex, and patient age 55 years or older. On multivariate analysis, pretreatment Hb of less than 14g/dl level and age 55 years or older were significantly associated with ribavirin dose reduction. The hazard ratios were 3.56 (95% confidence interval [CI], 1.48–8.53) for pretreatment Hb levels of less than 14g/dl, and 2.50 (95% CI, 1.05–5.94) for age 55 years or more.Conclusions Because patient age of 55 years or more, and Hb levels of less than 14g/dl are significant factors that influence ribavirin-induced hemolytic anemia, more careful monitoring is necessary during combination therapy for patients with these risk factors. 相似文献
69.
70.
Yukinobu Kodama Chikako Ohkubo Tomoaki Kurosaki Kanoko Egashira Kayoko Sato Shintaro Fumoto 《Journal of drug targeting》2015,23(1):43-51
Polynucleotides are anionic macromolecules which are expected to transfer into the targeted cells through specific uptake mechanisms. So, we developed polynucleotides coating complexes of plasmid DNA (pDNA) and polyethylenimine (PEI) for a secure and efficient gene delivery system and evaluated their usefulness. Polyadenylic acid (polyA), polyuridylic acid (polyU), polycytidylic acid (polyC), and polyguanylic acid (polyG) were examined as the coating materials. pDNA/PEI/polyA, pDNA/PEI/polyU, and pDNA/PEI/polyC complexes formed nanoparticles with a negative surface charge although pDNA/PEI/polyG was aggregated. The pDNA/PEI/polyC complex showed high transgene efficiency in B16-F10 cells although there was little efficiency in pDNA/PEI/polyA and pDNA/PEI/polyU complexes. An inhibition study strongly indicated the specific uptake mechanism of pDNA/PEI/polyC complex. Polynucleotide coating complexes had lower cytotoxicity than pDNA/PEI complex. The pDNA/PEI/polyC complex showed high gene expression selectively in the spleen after intravenous injection into mice. The pDNA/PEI/polyC complex showed no agglutination with erythrocytes and no acute toxicity although these were observed in pDNA/PEI complex. Thus, we developed polynucleotide coating complexes as novel vectors for clinical gene therapy, and the pDNA/PEI/polyC complex as a useful candidate for a gene delivery system. 相似文献