全文获取类型
收费全文 | 1543篇 |
免费 | 66篇 |
国内免费 | 33篇 |
专业分类
耳鼻咽喉 | 27篇 |
儿科学 | 62篇 |
妇产科学 | 20篇 |
基础医学 | 141篇 |
口腔科学 | 27篇 |
临床医学 | 131篇 |
内科学 | 405篇 |
皮肤病学 | 109篇 |
神经病学 | 48篇 |
特种医学 | 214篇 |
外科学 | 193篇 |
综合类 | 29篇 |
预防医学 | 81篇 |
眼科学 | 6篇 |
药学 | 63篇 |
中国医学 | 3篇 |
肿瘤学 | 83篇 |
出版年
2021年 | 10篇 |
2019年 | 15篇 |
2018年 | 20篇 |
2017年 | 19篇 |
2016年 | 16篇 |
2015年 | 26篇 |
2014年 | 29篇 |
2013年 | 72篇 |
2012年 | 26篇 |
2011年 | 20篇 |
2010年 | 53篇 |
2009年 | 66篇 |
2008年 | 26篇 |
2007年 | 40篇 |
2006年 | 41篇 |
2005年 | 40篇 |
2004年 | 25篇 |
2003年 | 25篇 |
2002年 | 25篇 |
2001年 | 35篇 |
2000年 | 22篇 |
1999年 | 28篇 |
1998年 | 85篇 |
1997年 | 72篇 |
1996年 | 77篇 |
1995年 | 52篇 |
1994年 | 63篇 |
1993年 | 51篇 |
1992年 | 21篇 |
1991年 | 22篇 |
1990年 | 29篇 |
1989年 | 48篇 |
1988年 | 45篇 |
1987年 | 40篇 |
1986年 | 35篇 |
1985年 | 30篇 |
1984年 | 28篇 |
1983年 | 14篇 |
1982年 | 21篇 |
1981年 | 18篇 |
1980年 | 13篇 |
1979年 | 18篇 |
1978年 | 14篇 |
1977年 | 17篇 |
1976年 | 16篇 |
1975年 | 12篇 |
1973年 | 15篇 |
1972年 | 11篇 |
1970年 | 7篇 |
1957年 | 7篇 |
排序方式: 共有1642条查询结果,搜索用时 0 毫秒
21.
David E. Beck USAF MC Francis J. Harford Colonel USAF MC Jack A. DiPalm USAF MC 《Diseases of the colon and rectum》1985,28(7):491-495
Golytely, an oral gut lavage solution, was compared with a standard bowel cleansing preparation in patients undergoing elective colonic surgery. Sixty patients were randomly assigned to either a one-day preparation with Golytely and bisacodyl or a standard method using a three-day clear liquid diet, cathartics, and enemas. Colon cleansing was better with Golytely (100 percent optimal cleansing vs. 64 percent, P less than 0.05). Patients receiving Golytely had less weight loss and found this preparation more tolerable. Quantitative stool cultures before and after preparation and intraoperatively were not significantly different between the two preparations. In this surgical bowel preparation study, Golytely and Bisacodyl were found to be safe, rapid, and effective. The preparation was well tolerated by patients and has become our preferred method of colonic cleansing. 相似文献
22.
23.
The effects of lithium on the microtubular and microfilament systems of neutrophil granulocytes is described. The phagocytic capacity of human neutrophils was reduced or inhibited by using vinblastine or cytochalasin B. Lithium at concentrations ranging from 0.5 to 2.0 mEq/l proved to be capable of antagonising the action of vinblastine, whereas the action of cytochalasin B was found to be unaffected by lithium. Based on the antagonising effect of lithium on vinblastine-induced inhibition of phagocytosis, it is suggested that lithium acts--at therapeutically achievable levels--on the microtubular system of neutrophils, possibly through modulation of cyclic AMP levels. 相似文献
24.
LI Juncos LA Juncos MC Ferrer AH Sampaolessi JC Romero 《American journal of kidney diseases》1999,33(1):43-51
In congestive heart failure (CHF), the neurohormonal mechanisms that cause renal vasoconstriction, particularly those depending on the renin-angiotensin system, could interfere with renal vasodilating mechanisms. To elucidate this issue, we studied the kidney response to an amino acid infusion (known to cause renal vasodilation in healthy individuals) in eight patients with CHF. We found that the amino acid infusion (0.7 mL/kg/h of a 10% solution) elicited no renal hemodynamic response, in marked contrast to healthy subjects. We next hypothesized that the renin-angiotensin system (known to be activated in heart failure) has a role in the lack of response to the amino acid infusion. To test this hypothesis, we repeated the study after two 5-mg doses of enalapril, an inhibitor of the angiotensin-converting enzyme, administered 12 hours apart. After enalapril treatment, the amino acid infusion caused a 45% increase in mean renal blood flow (RBF) from 383 +/- 55 to 557 +/- 51 mL/min at the fifth hour (P < 0.05). This normalization of the renal response to the amino acid infusion occurred without changes in cardiac output or in systemic vascular resistance. Hence, the renal fraction of the cardiac output increased during the amino acid infusion. The recovery of the renal vascular response was not accompanied by an increase in glomerular filtration rate (GFR; filtration fraction decreased), suggesting a predominant efferent arteriole dilatation. Our study shows that, in heart failure, the kidney loses its ability to increase RBF in response to an amino acid load. This lack of renal vascular response can be restored by inhibiting the renin-angiotensin system and is unrelated to changes in systemic hemodynamics. 相似文献
25.
26.
27.
Ambrogi MC Dini P Boni G Melfi F Lucchi M Fanucchi O Mariani G Mussi A 《Surgical endoscopy》2005,19(12):1644-1647
BACKGROUND: Preoperative procedures are often necessary to localize pulmonary nodules during thoracoscopic resection in order to reduce the necessity of resorting to thoracotomy. The aim of this report is to describe the strategy we developed to limit preoperative techniques without reducing the thoracoscopic success rate of localization.METHODS: Between January 2000 and December 2003, 183 patients underwent video thoracoscopic resection of small pulmonary nodules. The patients were divided into two groups on the basis of the radiological features of the nodule. The subjects in group 1 were operated on directly, and endothoracic ultrasonography was performed when necessary. The subjects in group 2 underwent preoperative radionuclide labeling of the nodule. RESULTS: In group 1, 112 out of 119 nodules (94%) were localized. Twenty-five out of 32 lesions, neither visible nor palpable, were found by endothoracic ultrasonography. In group 2, we localized 62 out of 64 nodules (97%). CONCLUSIONS: Currently, we cannot completely avoid preoperative labeling techniques for thoracoscopic resection of small pulmonary nodules. However, correct patient selection may limit this necessity, without an increased conversion rate to thoracotomy, if endothoracic ultrasonography is available. 相似文献
28.
29.
30.
Krista Kupres DO Capt Usa MC Steven E. Rasmussen MD MAJ Usaf Fs MC John G. Albertini MD MAJ Usaf MC 《Dermatologic surgery》2002,28(5):388-389
BACKGROUND: Low cost, nonsterile examination gloves are used routinely to perform various dermatologic procedures. OBJECTIVE: To evaluate the perforation rate of nonsterile examination gloves in routine dermatologic procedures. METHODS: Three hundred fifty nonsterile latex examination gloves used to perform shave biopsies were evaluated for perforations using an air inflation/water submersion method. Ninety gloves, which were intentionally perforated with a 30-gauge needle, were used as controls to assess our evaluation method. RESULTS: Eight of the 350 gloves were found to have a perforation, which corresponds to a 2.3% perforation rate. Seven of the eight perforations were found in the web space between the second and third finger sleeves, with one being an obvious manufacturing error. All 90 perforations of the control group were correctly identified. CONCLUSION: There appears to be a very low risk of glove perforation when nonsterile examination gloves are used in routine dermatologic procedures. 相似文献