收费全文 | 14706篇 |
免费 | 1692篇 |
国内免费 | 83篇 |
耳鼻咽喉 | 209篇 |
儿科学 | 149篇 |
妇产科学 | 183篇 |
基础医学 | 1154篇 |
口腔科学 | 6803篇 |
临床医学 | 653篇 |
内科学 | 2239篇 |
皮肤病学 | 138篇 |
神经病学 | 858篇 |
特种医学 | 424篇 |
外国民族医学 | 1篇 |
外科学 | 1582篇 |
综合类 | 61篇 |
预防医学 | 430篇 |
眼科学 | 163篇 |
药学 | 590篇 |
中国医学 | 6篇 |
肿瘤学 | 838篇 |
2023年 | 375篇 |
2022年 | 66篇 |
2021年 | 172篇 |
2020年 | 188篇 |
2019年 | 146篇 |
2018年 | 385篇 |
2017年 | 435篇 |
2016年 | 500篇 |
2015年 | 589篇 |
2014年 | 636篇 |
2013年 | 700篇 |
2012年 | 615篇 |
2011年 | 697篇 |
2010年 | 621篇 |
2009年 | 763篇 |
2008年 | 619篇 |
2007年 | 617篇 |
2006年 | 634篇 |
2005年 | 546篇 |
2004年 | 578篇 |
2003年 | 647篇 |
2002年 | 605篇 |
2001年 | 375篇 |
2000年 | 377篇 |
1999年 | 358篇 |
1998年 | 357篇 |
1997年 | 304篇 |
1996年 | 272篇 |
1995年 | 244篇 |
1994年 | 236篇 |
1993年 | 195篇 |
1992年 | 329篇 |
1991年 | 239篇 |
1990年 | 232篇 |
1989年 | 218篇 |
1988年 | 223篇 |
1987年 | 189篇 |
1986年 | 149篇 |
1985年 | 153篇 |
1984年 | 123篇 |
1983年 | 125篇 |
1982年 | 79篇 |
1981年 | 50篇 |
1980年 | 42篇 |
1979年 | 44篇 |
1977年 | 41篇 |
1975年 | 36篇 |
1974年 | 42篇 |
1973年 | 36篇 |
1972年 | 37篇 |
Results obtained from 22 centres from 12 countries indicated that the majority of the centres included a dental examination in their routine protocol and required completion of any necessary dental treatment before transplantation. However, full agreement among all these centres on the necessity for dental examination as part of the protocol has not yet been reached. 相似文献
Design: Prospective pharmacokinetic study of sevofurane administration in human subjects.
Setting: Inpatient surgery clinic at a university medical center.
Patients: Thirty-two Japanese patients, free of systemic diseases, undergoing minor elective surgery with endotracheal general anesthesia.
Interventions: The patients were assigned randomly to one of four groups: halothane, enflurane, isofurane, or sevofurane. One of the four volatile anesthetics being investigated [equivalent to 1.1 minimum alveolar concentration (MAC): halothane, 0.85%; enfurane, 1.85%; isofurane, 1.27%; and sevofurane, 1.88%; in inspired concentrations throughout the first hour of anesthesia] was administered for 60 minutes.
Measurements and Main Results: In all patients, serum and urinary fluoride concentrations were measured. The concentrations of all gases were measured separately with a mass spectrometer. The cumulative uptake of each anesthetic agent during a certain period was calculated as an integration of the uptake rate per minute. The results for one-hour inhalation of sevofurane (1.1 MAC) showed an uptake (corrected for body surface area and MAC) of 490 ml/m2/MAC and estimated degradation rate of 3.3%. For purposes of comparison, similar studies of halothane (uptake, 653 ml/m2/MAC; degradation rate 15.7%), enfurane (1150 ml/m2/MAC; 1.3%), and isofurane (439 ml/m2/MAC; 0.6%) were also conducted. Sevofurane had a peak serum inorganic fluoride concentration of 19.3 μmol/L, and no abnormality in hepatic or renal functions was observed in any of the subjects during the two weeks postoperatively.
Conclusions: Accurate determinations of uptake and degradation rate for sevoflurane and three other volatile anesthetics in Japanese patients were obtained. These findings have established that, despite its relatively large MAC *1.71%), sevoflurane has a small uptake due to its low solubility. However, the degradation rade was shown to be as high as 3.3%, resulting in a higher serum fluoride concentration than seen after administration of isoflurane, halothane, and (possibly) enflurane. 相似文献