全文获取类型
收费全文 | 54865篇 |
免费 | 4630篇 |
国内免费 | 115篇 |
专业分类
耳鼻咽喉 | 449篇 |
儿科学 | 2088篇 |
妇产科学 | 1421篇 |
基础医学 | 7840篇 |
口腔科学 | 1257篇 |
临床医学 | 7396篇 |
内科学 | 10700篇 |
皮肤病学 | 996篇 |
神经病学 | 5389篇 |
特种医学 | 1306篇 |
外科学 | 5301篇 |
综合类 | 613篇 |
一般理论 | 68篇 |
预防医学 | 6547篇 |
眼科学 | 864篇 |
药学 | 3267篇 |
2篇 | |
中国医学 | 55篇 |
肿瘤学 | 4051篇 |
出版年
2023年 | 455篇 |
2022年 | 628篇 |
2021年 | 1349篇 |
2020年 | 997篇 |
2019年 | 1490篇 |
2018年 | 1647篇 |
2017年 | 1320篇 |
2016年 | 1449篇 |
2015年 | 1528篇 |
2014年 | 1910篇 |
2013年 | 2855篇 |
2012年 | 3996篇 |
2011年 | 4141篇 |
2010年 | 2287篇 |
2009年 | 2023篇 |
2008年 | 3352篇 |
2007年 | 3479篇 |
2006年 | 3414篇 |
2005年 | 3266篇 |
2004年 | 3102篇 |
2003年 | 2919篇 |
2002年 | 2614篇 |
2001年 | 611篇 |
2000年 | 539篇 |
1999年 | 544篇 |
1998年 | 612篇 |
1997年 | 492篇 |
1996年 | 433篇 |
1995年 | 426篇 |
1994年 | 365篇 |
1993年 | 348篇 |
1992年 | 378篇 |
1991年 | 332篇 |
1990年 | 305篇 |
1989年 | 274篇 |
1988年 | 278篇 |
1987年 | 241篇 |
1986年 | 231篇 |
1985年 | 255篇 |
1984年 | 214篇 |
1983年 | 204篇 |
1982年 | 199篇 |
1981年 | 194篇 |
1980年 | 162篇 |
1979年 | 172篇 |
1978年 | 135篇 |
1977年 | 123篇 |
1973年 | 118篇 |
1972年 | 109篇 |
1971年 | 105篇 |
排序方式: 共有10000条查询结果,搜索用时 16 毫秒
1.
2.
3.
4.
Carmine Nieuwstraten N Renee Labiris Anne Holbrook 《Revue canadienne de psychiatrie》2006,51(5):300-316
OBJECTIVE: Antidepressants are commonly used drugs with potential for numerous drug interactions. This study aims to systematically review the literature on drug interactions with antidepressants. METHODS: We searched MEDLINE (1966 to November 2003) and EMBASE (1980 to 2003), using the heading drug interactions combined with individual antidepressant names. We restricted searches to English-language articles and human studies. We screened drug interaction texts and review articles for relevant studies. We included articles reporting original human data on drug interactions with antidepressants commonly used in North America. Articles were independently evaluated by 2 reviewers on clinical effect, clinical significance, and quality of evidence. Discrepancies were resolved by consensus. RESULTS: There were 904 eligible interactions, involving 9509 patients, for a total of 598 summary interactions. Of these, 439 (73%) demonstrated an interaction, 148 (25%) had no effect, and 11 (2%) had conflicting evidence. For 510 interactions (85%), the quality of evidence was poor. It was fair for 67 (11%) interactions and good for 10 (2%) interactions. There were no interactions with excellent quality of evidence. There were 145 (24%) interactions of major clinical significance. These were predominantly hypertensive emergencies and serotonin syndrome. Most interacting drugs had central nervous system (CNS) activity. As expected, monoamine oxidase inhibitors (MAOIs) appear to be the most problematic family in terms of potential for serious drug interactions. CONCLUSIONS: Drug interactions with antidepressants are an important cause for concern, but this concern is based primarily on poor evidence. We recommend caution when combining antidepressants with other CNS drugs, particularly when coadministering MAOIs with other substances. 相似文献
5.
Anne Pavy-Le Traon Richard L Hughson Claire Thalamas Monique Galitsky Nelly Fabre Olivier Rascol Jean-Michel Senard 《Movement disorders》2006,21(12):2122-2126
Patients with multiple system atrophy (MSA) present large changes in blood pressure (BP) due to autonomic disturbances. We analyzed how this change may influence dynamic cerebral autoregulation (DCA). Simultaneous recordings of arterial BP (Finapres) and middle cerebral artery (MCA) blood flow velocity (BFV) (transcranial Doppler) were performed in 10 patients with MSA (61 +/- 12 yr of age) and 12 healthy volunteers (61 +/- 11 yr of age): cerebral BFV response to oscillations in mean BP was studied in the supine position by cross-spectral analysis of mean BP and mean MCA BFV. The DCA was also studied during the decrease in BP the first seconds when standing up from a sitting position by the assessment of the cerebrovascular resistance index (CR; mean BP/mean MCA BFV ratio). The MCA BFV/BP cross-spectral analysis showed a phase for the mid-frequency band (0.07-0.2 Hz) significantly larger in MSA, suggesting more active autoregulation in response to larger changes in BP. Changes in CR reflecting the rate of autoregulation, when standing did not differ between the two groups. These data suggest that dynamic cerebral autoregulation is preserved in MSA. 相似文献
6.
This is the third and final part of a series of articles that report the findings of a study that investigated the effects of a summer externship program on the transition into a professional role among nurses who participated in a summer nurse externship program at an acute care pediatric hospital. Specifically, this article reports the retention and recruitment benefits of a summer nurse externship program for the institution from 1998 through 2003. A total of 153 externs out of the 193 (79.0%) assumed a registered nurse position at the institution, and 77% remained in that role for 12 months. Overall, the nurse extern program for this institution appeared to be an effective recruitment and retention strategy that is on par with the institution and national data for retention and turnover data. 相似文献
7.
Postpartum fatigue is a normal condition that most women experience. Breastfeeding is often associated in women's minds as contributing to the feeling of overall perceived fatigue, and many women indicate that they have ceased breastfeeding because of fatigue. However, the relationship between feeding choice and perceived fatigue has never been established. Two hundred and fifty-three women participated in a study examining whether perceived fatigue differed for bottle-feeding and breastfeeding women at 3 different times during the postpartum period (2-4 days, 6 weeks, and 12 weeks postpartum). Results showed no significant differences for these 2 groups, suggesting that perceived fatigue during the postpartum period is not dependent on feeding choice. Additional analyses examining other variables with a potential effect were nonsignificant. Because perceived physical fatigue does not appear to be dependent on feeding choice, women should be prepared for the feeling of perceived fatigue during the postpartum period while at the same time be reassured that feeding choice is not correlated. 相似文献
8.
9.
Marie-Paule Roth Hlne Coppin Patrick Descoins Jean-Bernard Ruidavets Anne Cambon-Thomsen Michel Clanet 《Journal of neuroimmunology》1991,34(2-3):215-222
The polymorphism at the HLA-DPB1 locus has been characterized in a large number of patients with multiple sclerosis (n = 112) and in healthy controls (n = 115). Both patients and controls lived in the southwest of France (in the Pyrénées Atlantiques) and had similar ethnic background. The typing procedure involved the selective amplification of the second exon of the DPB1 locus by polymerase chain reaction, followed by hybridization of the amplified DNA with 14 sequence-specific oligonucleotide probes. Individual alleles were identified by the pattern of hybridization of the different probes. The distribution of the DPB1 alleles was not significantly different in multiple sclerosis patients and controls (p = 0.11). This does not corroborate the reported association of multiple sclerosis with the primed lymphocyte typing (PLT)-defined DPw4 specificity and is not in favour of a role played by polymorphic residues of the DP molecule in susceptibility to multiple sclerosis. 相似文献
10.
J E Richards A H Parmelee L Beckwith 《Electroencephalography and clinical neurophysiology》1986,64(1):1-11
Power spectral and discriminant analysis techniques were used to compare EEG records obtained at term and at 3 months past term from 5 groups of varying risk and developmental outcome. The groups were: healthy full-terms; healthy pre-terms with normal outcomes; sick pre-terms with normal outcomes; sick pre-terms with delayed development; sick pre-terms with later neurological problems. The EEG samples recorded at term were identified as belonging to the correct subject group at 52-70% accuracy, 20% being chance for 5 groups. The accuracy varied with the 4 classes of EEG patterns used. The individual subjects were also classified into their correct groups with few exceptions. Similar success was obtained with EEG samples selected from recording at 3 months past term. The predominant power spectral discriminating features were changes in intra- and inter-hemispheric coherence, and increased power, particularly in the middle and higher frequency range. Thus, computer analyses of EEG samples, using features not readily identified visually, differentiated risk from non-risk infants and also differentiated infants with substantial neonatal medical complications who have good or poor developmental outcomes. 相似文献