全文获取类型
收费全文 | 14836篇 |
免费 | 716篇 |
国内免费 | 82篇 |
专业分类
耳鼻咽喉 | 126篇 |
儿科学 | 320篇 |
妇产科学 | 180篇 |
基础医学 | 1909篇 |
口腔科学 | 368篇 |
临床医学 | 986篇 |
内科学 | 4097篇 |
皮肤病学 | 239篇 |
神经病学 | 996篇 |
特种医学 | 616篇 |
外科学 | 2334篇 |
综合类 | 61篇 |
一般理论 | 1篇 |
预防医学 | 350篇 |
眼科学 | 311篇 |
药学 | 846篇 |
中国医学 | 15篇 |
肿瘤学 | 1879篇 |
出版年
2023年 | 91篇 |
2022年 | 183篇 |
2021年 | 398篇 |
2020年 | 176篇 |
2019年 | 270篇 |
2018年 | 322篇 |
2017年 | 279篇 |
2016年 | 315篇 |
2015年 | 331篇 |
2014年 | 422篇 |
2013年 | 514篇 |
2012年 | 891篇 |
2011年 | 967篇 |
2010年 | 554篇 |
2009年 | 491篇 |
2008年 | 845篇 |
2007年 | 893篇 |
2006年 | 811篇 |
2005年 | 793篇 |
2004年 | 780篇 |
2003年 | 750篇 |
2002年 | 782篇 |
2001年 | 328篇 |
2000年 | 368篇 |
1999年 | 268篇 |
1998年 | 161篇 |
1997年 | 136篇 |
1996年 | 92篇 |
1995年 | 117篇 |
1994年 | 89篇 |
1993年 | 84篇 |
1992年 | 202篇 |
1991年 | 182篇 |
1990年 | 178篇 |
1989年 | 165篇 |
1988年 | 151篇 |
1987年 | 151篇 |
1986年 | 153篇 |
1985年 | 145篇 |
1984年 | 92篇 |
1983年 | 74篇 |
1982年 | 60篇 |
1979年 | 69篇 |
1978年 | 44篇 |
1977年 | 41篇 |
1975年 | 33篇 |
1974年 | 46篇 |
1972年 | 40篇 |
1971年 | 32篇 |
1969年 | 37篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Shimon Kurasawa Takahiro Imaizumi Shoichi Maruyama Keitaro Tanaka Yoko Kubo Mako Nagayoshi Hiroaki Ikezaki Sadao Suzuki Teruhide Koyama Chihaya Koriyama Aya Kadota Sakurako Katsuura-Kamano Kiyonori Kuriki Kenji Wakai Keitaro Matsuo 《International journal of cancer. Journal international du cancer》2023,153(4):732-741
The association between kidney function and cancer incidence is inconsistent among previous reports, and data on the Japanese population are lacking. It is unknown whether kidney function modifies the cancer risk of other factors. We aimed to evaluate the association of estimated glomerular filtration rate (eGFR) with cancer incidence and mortality in 55 242 participants (median age, 57 years; 55% women) from the Japan Multi-Institutional Collaborative Cohort Study. We also investigated differences in cancer risk factors between individuals with and without kidney dysfunction. During a median 9.3-year follow-up period, 4278 (7.7%) subjects developed cancer. Moderately low and high eGFRs were associated with higher cancer incidence; compared with eGFR of 60-74 ml/min/1.73 m2, the adjusted hazard ratios (HRs) (95% confidence intervals [CIs]) for eGFRs of ≥90, 75-89, 45-59, 30-44 and 10-29 ml/min/1.73 m2 were 1.18 (1.07-1.29), 1.09 (1.01-1.17), 0.93 (0.83-1.04), 1.36 (1.00-1.84) and 1.12 (0.55-2.26), respectively. High eGFR was associated with higher cancer mortality, while low eGFR was not; the adjusted subdistribution HRs (95% CIs) for eGFRs of ≥90 and 75-89 ml/min/1.73 m2 were 1.58 (1.29-1.94) and 1.27 (1.08-1.50), respectively. Subgroup analyses of participants with eGFRs ≥60 and <60 ml/min/1.73 m2 revealed elevated cancer risks of smoking and family history of cancer in those with eGFR <60 ml/min/1.73 m2, with significant interactions. Our findings suggest that the relationship between eGFR and cancer incidence was U-shaped. Only high eGFR was associated with cancer mortality. Kidney dysfunction enhanced cancer risk from smoking. 相似文献
3.
4.
5.
Lesley A. Inker Morgan E. Grams Andrew S. Levey Josef Coresh Massimo Cirillo John F. Collins Ron T. Gansevoort Orlando M. Gutierrez Takayuki Hamano Gunnar H. Heine Shizukiyo Ishikawa Sun Ha Jee Florian Kronenberg Martin J. Landray Katsuyuki Miura Girish N. Nadkarni Carmen A. Peralta Dietrich Rothenbacher Mark Woodward 《American journal of kidney diseases》2019,73(2):206-217
6.
7.
Yamaoka Mai Yoshida Mahoko Nakashima Ayumu Doi Shigehiro Naito Takayuki Masaki Takao 《Clinical and experimental nephrology》2022,26(11):1111-1118
Clinical and Experimental Nephrology - The association between N-terminal pro-brain natriuretic peptide (NT-proBNP) and stroke in Japanese hemodialysis (HD) outpatients is unclear. Therefore, in... 相似文献
8.
Takayuki Sakurai Satoshi Watanabe Minoru Kimura Masahiro Sato 《Reproductive Medicine and Biology》2006,5(1):43-50
Background and Aims: The aim of this study was to determine which mouse strains exhibit tolerance to cooling when fertilized oocytes have been stored at 4°C.
Methods: In-vitro -fertilization-derived oocytes of eight mouse strains were incubated at 4°C in 20 mmol/L Hepes-potassium modified simplex optimized medium (KSOM) medium for 0, 24, 48, 60 or 72 h, and then returned to normal culture conditions at 37°C in KSOM medium. The rates of development of cultured oocytes into blastocysts and cell numbers of blastocysts were examined. In some cases, a Comet assay was carried out to evaluate DNA damage. In addition, the effects of β-mercaptoethanol on the development of the 4°C-treated oocytes were assessed.
Results: Of the eight strains tested, BDF1, B6C3F1 and FVB/N strains exhibited relatively higher degrees of tolerance to 4°C treatment and approximately 90%, 83% and 78% of oocytes treated at 4°C for 48 h developed to morphologically normal blastocysts, respectively. Comet assay revealed no clear DNA damage in oocytes treated at 4°C. Treatment with β-mercaptoethanol failed to improve the in vitro survival rate of low-temperature-treated oocytes.
Conclusion: Strain differences were observed in tolerance to cooling treatment when fertilized oocytes were temporarily treated with 4°C, although the reasons for this remain unclear. (Reprod Med Biol 2006; 5 : 43–50) 相似文献
Methods: In-vitro -fertilization-derived oocytes of eight mouse strains were incubated at 4°C in 20 mmol/L Hepes-potassium modified simplex optimized medium (KSOM) medium for 0, 24, 48, 60 or 72 h, and then returned to normal culture conditions at 37°C in KSOM medium. The rates of development of cultured oocytes into blastocysts and cell numbers of blastocysts were examined. In some cases, a Comet assay was carried out to evaluate DNA damage. In addition, the effects of β-mercaptoethanol on the development of the 4°C-treated oocytes were assessed.
Results: Of the eight strains tested, BDF1, B6C3F1 and FVB/N strains exhibited relatively higher degrees of tolerance to 4°C treatment and approximately 90%, 83% and 78% of oocytes treated at 4°C for 48 h developed to morphologically normal blastocysts, respectively. Comet assay revealed no clear DNA damage in oocytes treated at 4°C. Treatment with β-mercaptoethanol failed to improve the in vitro survival rate of low-temperature-treated oocytes.
Conclusion: Strain differences were observed in tolerance to cooling treatment when fertilized oocytes were temporarily treated with 4°C, although the reasons for this remain unclear. (Reprod Med Biol 2006; 5 : 43–50) 相似文献
9.
Katsuo Kamata Ayako Makino Noriyasu Kanie Shu-ichi Oda Takayuki Matsumoto Tsuneo Kobayashi Toyohiko Kikuchi Masato Nishimura Toshio Honda 《Journal of Smooth Muscle Research》2006,42(2-3):75-88
Anthocyanins, which are responsible for a variety of bright colors (including red, blue, and purple) in fruits, vegetables, and flowers, are consumed as dietary polyphenols. Anthocyanin-containing fruits are thought to decrease coronary heart disease and are used in anti-diabetic preparations. Diabetes is associated with a variety of cardiovascular complications that may be mediated by endothelial dysfunction, and so this study was designed mainly to characterize the influence of a synthesized anthocyanidin derivative (HK-008) over acetylcholine (ACh)-induced relaxation in mesenteric arterial beds isolated from rats. In a glucose-tolerance test in intact rats, HK-008 (30 mg/kg) reduced the glucose level as effectively as the same dose of glibenclamide. The aortic relaxation induced by pinacidil (an ATP-sensitive potassium channel opener) was greatly inhibited by glibenclamide (10 microM), and also significantly inhibited by HK-008 (10 microM). Interestingly, the ACh-induced relaxation in the perfused, preconstricted mesenteric arterial bed was significantly enhanced by HK-008 (10 microM), and this enhancement was significantly attenuated by indomethacin (10 microM). The ACh-induced mesenteric relaxation was impaired by an increase in oxidative stress, viz. superoxide-generating treatment [xanthine oxidase (XO; 0.1 U/ml) plus hypoxanthine (HX; 10 microM)]. However, this impairment was strongly suppressed by HK-008 (10 microM). These results suggest that HK-008 increases endothelium-induced relaxation by suppressing oxidative stress or modulating prostanoids signaling. This compound may therefore be useful against certain cardiovascular disorders. 相似文献
10.
CYP2E1 and ALDH2 Genotypes and Alcohol Dependence in Japanese 总被引:2,自引:0,他引:2
Kazuhiko Iwahashi Yoshinori Matsuo Hiroshi Suwaki Kazuhiko Nakamura Yoshiyuki Ichikawa 《Alcoholism, clinical and experimental research》1995,19(3):564-566
The genotypes of the CYP2E1 and ALDH2 loci of alcoholic (alcohol dependence) and nonalcoholic (healthy) Japanese were investigated to examine the relationship between the polymorphism of CYP2E1 (C1 /C2 ) and ALDH2 ( ALDH2*1/ALDH2*2 ), and the susceptibility to alcoholism. There was no significant difference in C2 gene frequency between alcoholics (0.19) and nonalcoholics (controls) (0.20), whereas there was a significant difference in ALDH2 allele frequency, suggesting that, in Japanese, the C2 genotype of CYP2E1 may have nothing to do with the risk of developing alcohol dependence. However, the ALDH2*1 allele may influence drinking behavior and the development of alcohol dependence. Furthermore, racial interethnic differences in the frequency of the mutated allele of the CYP2E1 gene (CJ were found, like the ALDH2 gene. Japanese healthy controls showed a significantly higher frequency of the C2 allele than did Swedish healthy controls (0.05; reported by Persson et al., FEBS Lett. 319:207-211,1993). 相似文献