全文获取类型
收费全文 | 62843篇 |
免费 | 6335篇 |
国内免费 | 106篇 |
专业分类
耳鼻咽喉 | 499篇 |
儿科学 | 1920篇 |
妇产科学 | 1386篇 |
基础医学 | 8648篇 |
口腔科学 | 1408篇 |
临床医学 | 7796篇 |
内科学 | 12208篇 |
皮肤病学 | 1014篇 |
神经病学 | 5515篇 |
特种医学 | 2299篇 |
外国民族医学 | 6篇 |
外科学 | 7886篇 |
综合类 | 1287篇 |
一般理论 | 40篇 |
预防医学 | 7463篇 |
眼科学 | 1111篇 |
药学 | 4910篇 |
中国医学 | 90篇 |
肿瘤学 | 3798篇 |
出版年
2023年 | 372篇 |
2022年 | 743篇 |
2021年 | 1404篇 |
2020年 | 795篇 |
2019年 | 1426篇 |
2018年 | 1587篇 |
2017年 | 1122篇 |
2016年 | 1241篇 |
2015年 | 1394篇 |
2014年 | 1859篇 |
2013年 | 2422篇 |
2012年 | 3639篇 |
2011年 | 3625篇 |
2010年 | 1925篇 |
2009年 | 1780篇 |
2008年 | 3024篇 |
2007年 | 3101篇 |
2006年 | 2964篇 |
2005年 | 2811篇 |
2004年 | 2580篇 |
2003年 | 2315篇 |
2002年 | 2214篇 |
2001年 | 1597篇 |
2000年 | 1528篇 |
1999年 | 1518篇 |
1998年 | 709篇 |
1997年 | 544篇 |
1996年 | 531篇 |
1995年 | 527篇 |
1994年 | 471篇 |
1993年 | 503篇 |
1992年 | 1229篇 |
1991年 | 1143篇 |
1990年 | 1079篇 |
1989年 | 1050篇 |
1988年 | 983篇 |
1987年 | 976篇 |
1986年 | 985篇 |
1985年 | 904篇 |
1984年 | 779篇 |
1983年 | 642篇 |
1982年 | 432篇 |
1979年 | 588篇 |
1978年 | 489篇 |
1977年 | 373篇 |
1976年 | 393篇 |
1974年 | 434篇 |
1973年 | 403篇 |
1972年 | 389篇 |
1969年 | 359篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Endoscopic balloon dilatation as a therapeutic option in the management of intestinal strictures resulting from Crohn's disease 总被引:5,自引:0,他引:5
Endoscopic balloon dilatation was undertaken in seven patients who presented with obstructive symptoms resulting from Crohn's disease. Five patients had strictures from recurrent disease at the site of an ileotransverse anastomosis, one had duodenal stenosis and one a colonic stricture. The procedures were performed under intravenous sedation on one to four occasions (median 2) and were uncomplicated. Sustained improvement over an 18-24-month follow-up period was achieved in five patients, but dilatation was unsuccessful in two cases. Endoscopic balloon dilatation is a safe and effective option in selected patients with intestinal strictures resulting from Crohn's disease and may overcome the need for surgery. 相似文献
12.
OBJECTIVE: The authors examined whether physicians' use of computerized decision aids affects patient satisfaction and/or blame for medical outcomes. METHOD: Experiment 1: Fifty-nine undergraduates read about a doctor who made either a correct or incorrect diagnosis and either used a decision aid or did not. All rated the quality of the doctor's decision and the likelihood of recommending the doctor. Those receiving a negative outcome also rated negligence and likelihood of suing. Experiment 2: One hundred sixty-six medical students and 154 undergraduates read negative-outcome scenarios in which a doctor either agreed with the aid, heeded the aid against his own opinion, defied the aid in favor of his own opinion, or did not use a decision aid. Subjects rated doctor fault and competence and the appropriateness of using decision aids in medicine. Medical students made judgments for themselves and for a layperson. RESULTS: Experiment 1: Using a decision aid caused a positive outcome to be rated less positively and a negative outcome to be rated less negatively. Experiment 2: Agreeing with or heeding the aid was associated with reduced fault, whereas defying the aid was associated with roughly the same fault as not using one at all. Medical students were less harsh than undergraduates but accurately predicted undergraduate's responses. CONCLUSION: Agreeing with or heeding a decision aid, but not defying it, may reduce liability after an error. However, using an aid may reduce favorability after a positive outcome. 相似文献
13.
Ronald Martin Jaime Williams Thomas Hadjistavropoulos Heather D Hadjistavropoulos Michael MacLean 《Revue canadienne de recherche en sciences infirmières》2005,37(2):142-164
The literature suggests that pain in the elderly, especially among seniors with dementia, is under-assessed and under-treated.This qualitative study solicited the perspectives of seniors, front-line nursing staff, nursing-home administrators, and informal caregivers of seniors with dementia on the current status of pain assessment and management. The views of these participants complement the research findings reported in the literature. While some of their explanations and potential solutions concerning under-treatment of pain in seniors echo views that have been presented in the literature, the participants also pointed to factors and avenues that have been given less formal consideration (e.g., systemic barriers to effective assessment and treatment of pain).They also highlighted the need for pain-control strategies beyond medication. The implications of these findings are discussed. 相似文献
14.
15.
16.
M P McMurry P N Hopkins R Gould K Engelbert-Fenton C Schumacher L L Wu R R Williams 《Journal of the American Dietetic Association》1991,91(1):57-65
We have developed a unique, family-oriented approach to lowering plasma cholesterol concentrations in persons with familial hyperlipidemias. The approach includes individual clinic visits and group nutrition classes and uses dietary goals outlined in The New American Diet. A series of 13 nutrition classes is presented to small groups, usually composed of relatives from pedigrees with familial hypercholesterolemia or other familial hyperlipidemias. Dietary action goals, cooking demonstrations, food tasting, and finger-stick plasma cholesterol determinations are important components of the classes. Problem-solving discussion is encouraged in the group. Over the past 4 years, 143 hyperlipidemic individuals, along with at least 94 unaffected family members, have participated in 31 groups, which have met for at least six classes. Many clinic participants lower plasma cholesterol by 20% or more. Keys to the success of this program include emphasizing dietary therapy, using the family setting for nutrition intervention, providing hands-on experience with food and recipes, promoting problem solving for dietary action goals, measuring blood cholesterol during classes, and encouraging long-term follow-up for participants with physicians and dietitians. 相似文献
17.
In 1984, in addition to its standard traditional curriculum, Rush Medical College (Chicago, Ill) developed a Socratic problem-based method of teaching basic science material called the alternative curriculum. As part of an evaluation of this new curriculum, students in the two curricula were compared using three traditional measurements: (1) test scores from the National Board of Medical Examiners, Part I; (2) test scores from the National Board of Medical Examiners, Part II; and (3) performance on an oral examination. Alternative curriculum students did not differ significantly from their traditional curriculum classmates on National Board of Medical Examiners, Part I and Part II total scores, although their subset scores on Part I did tend to be lower, reaching significance in one subset area. Differences in performance favoring the traditional curriculum were primarily seen in the early years of the program. Alternative curriculum students in the class matriculated in 1987 scored significantly higher in three of five categories on the oral examination. 相似文献
18.
Bill J Gurley Ashley Swain Gary W Barone D Keith Williams Philip Breen C Ryan Yates Leslie B Stuart Martha A Hubbard Yudong Tong Sreekhar Cheboyina 《Drug metabolism and disposition》2007,35(2):240-245
Phytochemical-mediated modulation of P-glycoprotein (P-gp) and other drug transporters may give rise to many herb-drug interactions. Serial plasma concentration-time profiles of the P-gp substrate, digoxin, were used to determine whether supplementation with goldenseal or kava kava modified P-gp activity in vivo. Twenty healthy volunteers were randomly assigned to receive a standardized goldenseal (3210 mg daily) or kava kava (1227 mg daily) supplement for 14 days, followed by a 30-day washout period. Subjects were also randomized to receive rifampin (600 mg daily, 7 days) and clarithromycin (1000 mg daily, 7 days) as positive controls for P-gp induction and inhibition, respectively. Digoxin (Lanoxin, 0.5 mg) was administered p.o. before and at the end of each supplementation and control period. Serial digoxin plasma concentrations were obtained over 24 h and analyzed by chemiluminescent immunoassay. Comparisons of area under the curve (AUC)((0-3)), AUC((0-24)), C(max,) CL/F, and elimination half-life were used to assess the effects of goldenseal, kava kava, rifampin, and clarithromycin on digoxin pharmacokinetics. Rifampin produced significant reductions (p < 0.01) in AUC((0-3)), AUC((0-24)), CL/F, t(1/2), and C(max), whereas clarithromycin increased these parameters significantly (p < 0.01). With the exception of goldenseal's effect on C(max) (14% increase), no statistically significant effects on digoxin pharmacokinetics were observed following supplementation with either goldenseal or kava kava. When compared with rifampin and clarithromycin, supplementation with these specific formulations of goldenseal or kava kava did not appear to affect digoxin pharmacokinetics, suggesting that these supplements are not potent modulators of P-gp in vivo. 相似文献
19.
Biologic distribution data in the rat were obtained for the alpha-1 adrenoceptor imaging agent (+/-) 2-[beta-(iodo-4-hydroxyphenyl)ethylaminomethyl]tetralone (HEAT) labeled with [125I]. The major excretory routes were through the liver (67%) and the kidney (33%). Internal radiation absorbed dose estimates to nine source organs, total body, the GI tract, gonads, and red bone marrow were calculated for the human using the physical decay data for [123I]. The critical organ was found to be the lower large intestine, receiving 1.1 rad per mCi of [123I]HEAT administered. The total-body dose was found to be 58 mrad per mCi. 相似文献
20.
The extracellular matrix of stratum corneum: role of lipids in normal and pathological function 总被引:4,自引:0,他引:4
The mammalian stratum corneum, formerly treated as a homogeneous film, is now more properly viewed as a two-compartment system. The cornified cell is protein-enriched and lipid-depleted, lying embedded in an expanded extracellular matrix of highly nonpolar lipids. Because of its strategic location between the cornified layer, this lipid matrix is responsible for many phenomena related to the permeability barrier, as well as cohesion and desquamation. Thus, manipulation of this compartment could lead to enhanced drug delivery and improved lubrication, as well. 相似文献