全文获取类型
收费全文 | 1950718篇 |
免费 | 171473篇 |
国内免费 | 5635篇 |
专业分类
耳鼻咽喉 | 29293篇 |
儿科学 | 64060篇 |
妇产科学 | 50670篇 |
基础医学 | 267970篇 |
口腔科学 | 52063篇 |
临床医学 | 182853篇 |
内科学 | 410982篇 |
皮肤病学 | 48577篇 |
神经病学 | 165239篇 |
特种医学 | 72176篇 |
外国民族医学 | 471篇 |
外科学 | 307353篇 |
综合类 | 31065篇 |
现状与发展 | 73篇 |
一般理论 | 708篇 |
预防医学 | 147127篇 |
眼科学 | 44294篇 |
药学 | 137364篇 |
7篇 | |
中国医学 | 4513篇 |
肿瘤学 | 110968篇 |
出版年
2021年 | 20510篇 |
2020年 | 19465篇 |
2019年 | 28544篇 |
2018年 | 38786篇 |
2017年 | 32410篇 |
2016年 | 34618篇 |
2015年 | 37654篇 |
2014年 | 51303篇 |
2013年 | 67450篇 |
2012年 | 74765篇 |
2011年 | 78076篇 |
2010年 | 54847篇 |
2009年 | 51219篇 |
2008年 | 71265篇 |
2007年 | 73706篇 |
2006年 | 75394篇 |
2005年 | 71807篇 |
2004年 | 67903篇 |
2003年 | 63929篇 |
2002年 | 62064篇 |
2001年 | 70493篇 |
2000年 | 71007篇 |
1999年 | 61514篇 |
1998年 | 21483篇 |
1997年 | 19055篇 |
1996年 | 18777篇 |
1995年 | 17726篇 |
1994年 | 15691篇 |
1993年 | 14196篇 |
1992年 | 46525篇 |
1991年 | 45456篇 |
1990年 | 44450篇 |
1989年 | 43088篇 |
1988年 | 40151篇 |
1987年 | 39100篇 |
1986年 | 37355篇 |
1985年 | 35505篇 |
1984年 | 26880篇 |
1983年 | 23438篇 |
1982年 | 14762篇 |
1979年 | 24855篇 |
1978年 | 17727篇 |
1977年 | 15448篇 |
1976年 | 14463篇 |
1975年 | 15751篇 |
1974年 | 18410篇 |
1973年 | 17758篇 |
1972年 | 16880篇 |
1971年 | 15631篇 |
1970年 | 14645篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
María Cabrerizo Gloria Trallero María José Pena Amaia Cilla Gregoria Megias Carmen Mu?oz-Almagro Eva Del Amo Diana Roda Ana Isabel Mensalvas Antonio Moreno-Docón Juan García-Costa Nuria Rabella Manuel Ome?aca María Pilar Romero Sara Sanbonmatsu-Gámez Mercedes Pérez-Ruiz María José Santos-Mu?oz Cristina Calvo And the study group of “Enterovirus parechovirus infections in children under ?years-old Spain” PI- 《European journal of pediatrics》2015,174(11):1511-1516
32.
33.
J. Rodríguez-Carrio A. Martínez-Zapico I. Cabezas-Rodríguez L. Benavente Á.I. Pérez-Álvarez P. López J.B. Cannata-Andía M. Naves-Díaz A. Suárez 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(2):135-143
Background and aims
Since accelerated atherosclerosis has been reported in systemic lupus erythematosus (SLE), predictive biomarkers of cardiovascular disease (CVD) are needed. Among non-traditional risk factors, bone mineral density (BMD) has been related to CVD. However, its role in SLE remains controversial. This study aims to analyze the associations of subclinical atherosclerosis with traditional and non-traditional CV risk factors.Methods and results
In a cross-sectional study, atherosclerosis burden was compared between 112 female SLE patients and 31 controls. Plaque number and carotid intima-media wall thickness (cIMT) were assessed by ultrasonography. In a retrospective study, BMD determinations obtained 5-years before the ultrasonography assessment were analyzed in a subgroup of 62 patients. Plaque frequency was increased in SLE, even in patients without CV events or carotid wall thickening. cIMT was increased in patients with CVD, positively correlated with body mass index (BMI). Interestingly, a paradoxical effect of BMI on carotid parameters was observed. Whereas underweight patients (BMI < 20) showed increased prevalence of carotid plaques with low cIMT, those with BMI > 30 showed higher cIMT and plaque burden. Overweight patients (25 < BMI<30) exhibited both elevated cIMT and plaque number. BMI was an independent predictor of BMD. In our retrospective study, patients with either clinical or subclinical CVD exhibited lower BMD levels than their CV-free counterparts. A low lumbar spine BMD independently predicted CVD development after adjusting for confounders.Conclusion
SLE was associated with a higher subclinical atherosclerosis burden, a bimodal effect being observed for BMI. Decreased BMD can be a CV risk biomarker in SLE. 相似文献34.
Laparoscopic surgery has several advantages over traditional surgery because it has been shown to be less invasive. The next logical step in the evolution of minimally invasive surgery may be to eliminate all abdominal incisions. The natural orifices provide a port of entry via the gastrointestinal tract to the peritoneal cavity. This approach would require the creation of a perforation, which is considered to be a major complication of endoscopy with significant morbidity and mortality. However, there are several recent studies that have described the technical feasibility and safety of a per‐oral transgastric approach to the peritoneal cavity using conventional endoscopes. Theoretically, this approach could reduce postoperative abdominal wall pain, wound infection, hernia formation, and adhesions. This article aims to summarize the current status of transgastric surgery, currently referred to as natural orifice transluminal endoscopic surgery (NOTES), and to address some of its future challenges. 相似文献
35.
N. SUVAJD
I V. EMERIKI‐MARTINOVI . ARANOVI M. PETROVI M. POPOVI V. ARTIKO M. UPI I. ELEZOVI 《International journal of laboratory hematology》2006,28(5):317-320
We report the case of a littoral‐cell angioma of the spleen, a recently described benign vascular tumour, whose imaging and pathological characteristics have been discussed only by a few authors. The diagnosis was made after elective splenectomy. The CT images, scintigraphy and histological specimens are presented, and differential diagnoses discussed. 相似文献
36.
37.
38.
39.
Barry L Eppley A Michael Sadove David Hennon John A van Aalst 《The Cleft palate-craniofacial journal》2006,43(3):374-378
OBJECTIVE: A series of nasopharyngeal appliance designs is presented that represents our evolving experience over a 20-year period in the adjunctive use of prosthetic stents in the surgical correction of nasopharyngeal stenosis. DESIGN: Retrospective assessment of effectiveness of two nasopharyngeal stenosis hollow stent designs in a consecutive series of patients for relief of nasal obstructive symptoms. SETTING: Tertiary academic medical center, Craniofacial Program at Children's Hospital. PATIENTS: Four patients with nasopharyngeal stenosis were treated with a preoperatively fabricated stent made from a clasped palatal appliance onto which hollow acrylic conduits were extended through surgically re-created pharyngeal ports. A subsequent set of four patients with nasopharyngeal stenosis were treated with intraoperatively-fashioned silastic grommets, as opposed to palatal appliances. INTERVENTIONS: Postoperative intraoral stenting of nasopharyngeal ports. MAIN OUTCOME MEASURES: Maintenance of pharyngeal port opening after 1 year, improvement in nasal airway obstructive symptoms. RESULTS: The palatal appliance stents were less well tolerated and had a lower maintenance of port patency after device removal (4 of 8, 50%). The silastic grommets provided better retention into the ports and increased patient tolerance, as well as better 1-year port maintenance (6 of 8, 75%). CONCLUSIONS: The grommet stent appliance offers numerous advantages over a conventional dental-clasped appliance for prosthetic nasopharyngeal stenting, including obviation of extensive preoperative preparation, ease of insertion and removal, and exchange of air during the stenting period. Improved nasopharyngeal patency with this device may be due to greater patient tolerance and subsequent longer use. 相似文献
40.
Peter G. Danias Thomas H. Hauser George Katsimaglis Rene M. Botnar Warren J. Manning 《Herz》2003,15(4):90-98
Coronary magnetic resonance angiography (CMRA) is a technique in clinical evolution. Current clinical applications include assessment for coronary anomalies, aneurysms, bypass graft patency, and, in experienced centers, the exclusion of proximal and multivessel coronary artery disease (CAD). As local expertise increases and more extensive multicenter data become available, additional applications will be established. CMRA promises to supplement and in some cases obviate the need for X-ray contrast angiography, and to expand our understanding of the pathophysiology of CAD. Zusammenfassung Die Magnetresonanzangiographie der Koronargefäße (CMRA) ist eine sich ständig weiterentwickelnde Technik. Etablierte Anwendungen sind zurzeit die Beurteilung von koronaren Anomalien, Aneurysmen und der Durchgängigkeit von Bypasses. Auch der Ausschluss proximaler Koronarstenosen und einer koronaren Mehrgefäßerkrankung ist in einigen spezialisierten Zentren möglich. Mit zunehmender Erfahrung der jeweiligen Anwender und der Verfügbarkeit von Ergebnissen großer multizentrischer Studien können zukünftig weitere klinische Anwendungen etabliert werden. In der Zukunft könnte die CMRA ergänzende Informationen zur Indikationsstellung einer konventionellen Röntgenangiographie bringen und in einigen Fällen diese Untersuchung sogar ersetzen. Die CMRA wird unseren Einblick in die Pathophysiologie der koronaren Herzerkrankung sicher erweitern. 相似文献