全文获取类型
收费全文 | 3857篇 |
免费 | 159篇 |
国内免费 | 34篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 86篇 |
妇产科学 | 42篇 |
基础医学 | 546篇 |
口腔科学 | 23篇 |
临床医学 | 757篇 |
内科学 | 858篇 |
皮肤病学 | 39篇 |
神经病学 | 311篇 |
特种医学 | 103篇 |
外科学 | 497篇 |
综合类 | 18篇 |
预防医学 | 177篇 |
眼科学 | 64篇 |
药学 | 263篇 |
中国医学 | 7篇 |
肿瘤学 | 244篇 |
出版年
2023年 | 12篇 |
2022年 | 22篇 |
2021年 | 37篇 |
2020年 | 18篇 |
2019年 | 33篇 |
2018年 | 49篇 |
2017年 | 47篇 |
2016年 | 39篇 |
2015年 | 64篇 |
2014年 | 99篇 |
2013年 | 130篇 |
2012年 | 256篇 |
2011年 | 289篇 |
2010年 | 151篇 |
2009年 | 172篇 |
2008年 | 281篇 |
2007年 | 303篇 |
2006年 | 286篇 |
2005年 | 304篇 |
2004年 | 287篇 |
2003年 | 312篇 |
2002年 | 255篇 |
2001年 | 44篇 |
2000年 | 41篇 |
1999年 | 41篇 |
1998年 | 47篇 |
1997年 | 35篇 |
1996年 | 35篇 |
1995年 | 45篇 |
1994年 | 36篇 |
1993年 | 23篇 |
1992年 | 22篇 |
1991年 | 28篇 |
1990年 | 14篇 |
1989年 | 15篇 |
1988年 | 21篇 |
1987年 | 12篇 |
1986年 | 12篇 |
1985年 | 11篇 |
1984年 | 19篇 |
1983年 | 10篇 |
1982年 | 14篇 |
1981年 | 11篇 |
1980年 | 11篇 |
1979年 | 14篇 |
1978年 | 5篇 |
1977年 | 8篇 |
1976年 | 3篇 |
1974年 | 4篇 |
1973年 | 5篇 |
排序方式: 共有4050条查询结果,搜索用时 15 毫秒
11.
Stéphanie Chasseigneaux Stéphane Haïk Isabelle Laffont-Proust Olivier De Marco Martine Lenne Jean-Philippe Brandel Jean-Jacques Hauw Jean-Louis Laplanche Katell Peoc’h 《Neuroscience letters》2006
A valine to isoleucine mutation at residue 180 was identified in a French patient with Creutzfeldt-Jakob disease (CJD). The mutation is located in the close vicinity of one of the two N-glycosylation sites of the cellular prion protein (PrPC). Western blot analysis revealed accumulation in the brain of the pathogenic proteinase K-resistant PrP (PrPSc) isoform with the notable absence of the diglycosylated band. The mutant protein expressed in CHO cells was correctly glycosylated, suggesting that the atypical glycosylation pattern of PrPSc was not due to the mutation at position 180. These results suggest that the diglycosylated form of the mutant PrP180I prevents its conversion into the pathogenic mutant form PrPSc180I, supporting a central role of N-linked glycan chains in the PrP conversion process. 相似文献
12.
Safety of cryopreservation straws for human gametes or embryos: a study with human immunodeficiency virus-1 under cryopreservation conditions 总被引:3,自引:0,他引:3
13.
Filali-Zegzouti Y Abdelmelek H Rouanet JL Cottet-Emard JM Pequignot JM Barré H 《Pflügers Archiv : European journal of physiology》2000,441(2-3):275-280
Physiological studies have shown that glucagon is a potential mediator of nonshivering thermogenesis (NST) in birds. The present work was undertaken in order to investigate whether the observed thermogenesis results from a direct action of glucagon on avian thermoregulatory mechanisms or in fact requires the participation of other agents such as catecholamines. Our experiments were performed using cold-acclimated (CA) ducklings which developed muscle NST. A comparison was made with thermoneutral (TN) ducklings of the same age. Our principal results showed that: (1) at ambient temperature (25 degrees C), circulating norepinephrine (NE) was markedly decreased in CA ducklings (-42%), while circulating epinephrine (E) did not undergo any consistent change; (2) in CA and TN ducklings, an intraperitoneal injection of glucagon (360 microg x kg(-1)) was followed after 10 min by prominent lipolysis and a large increase in circulating NE (4- to 6-fold) and E (14- to 17-fold), which was sustained for at least 1 h. The elevation of circulating NE was less pronounced in CA ducklings. The thermogenic action of glucagon in birds is probably indirect and involves at least the mobilization of lipids and sympatho-adrenal stimulation. The changes in peripheral noradrenergic activity during cold acclimation could be associated with adaptive changes leading to NST. 相似文献
14.
Cristina Mecucci Kristina Vermaelen Guido Tricot Andries Louwagie Jean-Louis Michaux André Bosly José Thomas Dario Barbieri Herman Van Den Berghe 《Cancer Genetics and Cytogenetics》1983,9(4):367-381
Anomalies of both No. 3 chromosomes, of the t(3q?; 3q+) type can be observed in human malignancy as reported previously. It is our experience that this anomaly is found predominantly in myeloproliferative disorders, as a rather rare event, though occurring more frequently than similar exchanges between other homologous chromosomes. Previous claims about a relationship between this anomaly and thrombocytosis could not be confirmed, but the features found in a few patients indicate that further research should be undertaken to clarify this point. 相似文献
15.
The role of Toll-like receptors and Nod proteins in bacterial infection 总被引:22,自引:0,他引:22
Our understanding of innate immunity in mammals has greatly expanded following the discovery of the family of membrane-bound receptors, called the Toll-like receptors (TLRs). More recently, the nucleotide-binding oligomerisation domain (Nod) molecules, Nod1 and Nod2, which are cytoplasmic surveillance proteins, have also been shown to be involved in the innate immune response. These two classes of detection molecules, classified as "pattern recognition receptors" (PRRs), detect microbial ligands in order to initiate a defense response to fight infectious disease. These microbial ligands or "pathogen-associated molecular patterns" (PAMPs), detected by TLRs and Nods are often structural components of the microorganism that are not subject to much variation. These include such factors as lipopolysaccharide (LPS) and peptidoglycan from the cell walls of bacteria. In order to understand the role of TLRs and Nod proteins in infectious disease in vivo it is important to define the site of interaction between PRRs and PAMPS. Additionally, the challenge of mice deficient in the various PRRs in natural infection models will help to decipher the contribution of these molecules not only in the innate immune response against pathogen infection but also how these proteins may instruct the adaptive immune response in order to have a tailored immune response against a particular microbe. 相似文献
16.
17.
Sandrine Imbeaud Rodofo Rey Philippe Berta Jean-Louis Chaussain Jan-Maarten Wit Robert H. Lustig Jeah-Yves Picard N. Josso 《European journal of pediatrics》1995,154(3):187-190
The presistent Müllerian duct syndrome, characterized by the presence of uterus and tubes in males, is a familial disorder due to defects of synthesis or action of anti-Müllerian hormone, a Sertoli cell glycoprotein responsible for the regression of Müllerian derivatives in normal male fetuses. Patients are normally virilized and testicular production of testosterone is normal. Both testes my be cryptorchild; alternatively, one may be descended into the inguinal canal or scrotum, together with the Müllerian derivatives, a condition known as hernia uteri inguinalis. We have recently observed three patients affected by the presistent Müllerian duct syndrome who experienced progressive degeneration of testicular tissue. In two, functional testicular tissue was still present some months after birth, but deteriortated progressively later. In one patient, testicular tissue was already absent at birth, but the normal virilization of external genitalia indicated that testicular degeneration must have occurred lat during fetal life, after the expected time of regression of male Müllerian ducts.Conclusion The high incidence of degeneration of testicular tissue in the presistent Müllerian duct syndrome could be indirectly linked to anatomical abnormalities which could favour testicular torsion, known to induce testicular regression. 相似文献
18.
Jean-Louis G Mendlowicz MV Von Gizycki H Zizi F Nunes J 《Journal of women's health & gender-based medicine》1999,8(8):1113-1117
Research evidence suggests that actigraphy is a very important instrument in documenting sleep/wake patterns of people with a variety of sleep disorders or motor dysfunctions. The present actigraphic investigation examined physical activity and sleep profiles as a function of gender in volunteers monitored in their natural environment. Irrespective of age, women exhibited better sleep quality than did men. This was demonstrated by higher sleep efficiency index and lower frequency of transitions between sleep and wakefulness. Additionally, women slept more than men and had shorter sleep onset latency. However, no significant gender effect on daytime activity level and circadian activity amplitude was observed. 相似文献
19.
Randomized, placebo-controlled trial of combined pentoxifylline and tocopherol for regression of superficial radiation-induced fibrosis. 总被引:3,自引:0,他引:3
Sylvie Delanian Raphael Porcher Saida Balla-Mekias Jean-Louis Lefaix 《Journal of clinical oncology》2003,21(13):2545-2550
PURPOSE: Radiation-induced fibrosis (RIF) is a rare morbid complication of radiotherapy, without an established method of management. RIF treatment with a combination of pentoxifylline (PTX) and alpha-tocopherol (vitamin E; Vit E) was recently prompted by the good results of a clinical trial and an animal study. The present double-blind, placebo-controlled, monocentric study was designed to assess the efficacy of this combination in treating RIF sequelae. PATIENTS AND METHODS: Twenty-four eligible women with 29 RIF areas involving the skin and underlying tissues were enrolled from December 1998 to April 2000. These patients, previously irradiated for breast cancer, were randomly assigned to four balanced treatment groups: (A) 800 mg/d of PTX and 1,000 U/d of Vit E; (B) PTX plus placebo; (C) placebo plus Vit E; and (D) placebo-placebo. The main end point measure was the relative regression of measurable RIF surface after 6 months of treatment. Assessment was completed by depth (with ultrasonography) and associated symptom measures. RESULTS: Twenty-two patients with 27 RIF areas were analyzed at 6 months. Mean RIF surface regression was significant with combined PTX/Vit E versus double placebo (60% +/- 10% v 43% +/- 17%; P =.038). The median slope for the speed of RIF surface area and volume regression was significantly higher for group A than groups B, C, and D. All treatments were well tolerated. CONCLUSION: Six months' treatment of combined PTX/Vit E can significantly reduce superficial RIF. Synergism between PTX and Vit E is likely, as treatment with each drug alone is ineffective, but these results require confirmation in larger series. 相似文献
20.
Darius Razavi Isabelle Merckaert Serge Marchal Yves Libert Sandrine Conradt Jacques Boniver Anne-Marie Etienne Ovide Fontaine Pascal Janne Jean Klastersky Christine Reynaert Pierre Scalliet Jean-Louis Slachmuylder Nicole Delvaux 《Journal of clinical oncology》2003,21(16):3141-3149
PURPOSE: Although there is wide recognition of the usefulness of improving physicians' communication skills, no studies have yet assessed the efficacy of post-training consolidation workshops. This study aims to assess the efficacy of six 3-hour consolidation workshops conducted after a 2.5-day basic training program. METHODS: Physicians, after attending the basic training program, were randomly assigned to consolidation workshops or to a waiting list. Training efficacy was assessed through simulated and actual patient interviews that were audiotaped at baseline and after consolidation workshops for the consolidation-workshop group, and approximately 5 months after the end of basic training for the waiting-list group. Communication skills were assessed according to the Cancer Research Campaign Workshop Evaluation Manual. Patients' perceptions of communication skills improvement were assessed using a 14-item questionnaire. RESULTS: Sixty-three physicians completed the training program. Communication skills improved significantly more in the consolidation-workshop group compared with the waiting-list group. In simulated interviews, group-by-time repeated measures analysis of variance showed a significant increase in open and open directive questions (P =.014) and utterances alerting patients to reality (P =.049), as well as a significant decrease in premature reassurance (P =.042). In actual patient interviews, results revealed a significant increase in acknowledgements (P =.022) and empathic statements (P =.009), in educated guesses (P =.041), and in negotiations (P =.008). Patients interacting with physicians who benefited from consolidation workshops reported higher scores concerning their physicians' understanding of their disease (P =.004). CONCLUSION: Consolidation workshops further improve a communication skills training program's efficacy and facilitate the transfer of acquired skills to clinical practice. 相似文献