全文获取类型
收费全文 | 1450篇 |
免费 | 97篇 |
专业分类
耳鼻咽喉 | 12篇 |
儿科学 | 52篇 |
妇产科学 | 24篇 |
基础医学 | 220篇 |
口腔科学 | 70篇 |
临床医学 | 125篇 |
内科学 | 397篇 |
皮肤病学 | 6篇 |
神经病学 | 103篇 |
特种医学 | 32篇 |
外科学 | 180篇 |
综合类 | 9篇 |
预防医学 | 64篇 |
眼科学 | 14篇 |
药学 | 105篇 |
中国医学 | 11篇 |
肿瘤学 | 123篇 |
出版年
2023年 | 5篇 |
2022年 | 7篇 |
2021年 | 21篇 |
2020年 | 18篇 |
2019年 | 35篇 |
2018年 | 52篇 |
2017年 | 23篇 |
2016年 | 28篇 |
2015年 | 32篇 |
2014年 | 37篇 |
2013年 | 63篇 |
2012年 | 90篇 |
2011年 | 100篇 |
2010年 | 50篇 |
2009年 | 47篇 |
2008年 | 60篇 |
2007年 | 79篇 |
2006年 | 87篇 |
2005年 | 85篇 |
2004年 | 56篇 |
2003年 | 52篇 |
2002年 | 44篇 |
2001年 | 31篇 |
2000年 | 23篇 |
1999年 | 15篇 |
1998年 | 9篇 |
1995年 | 14篇 |
1993年 | 6篇 |
1992年 | 21篇 |
1991年 | 21篇 |
1990年 | 23篇 |
1989年 | 28篇 |
1988年 | 20篇 |
1987年 | 29篇 |
1986年 | 38篇 |
1985年 | 16篇 |
1984年 | 18篇 |
1983年 | 18篇 |
1982年 | 14篇 |
1980年 | 9篇 |
1979年 | 14篇 |
1978年 | 12篇 |
1977年 | 8篇 |
1976年 | 6篇 |
1975年 | 6篇 |
1974年 | 10篇 |
1973年 | 15篇 |
1972年 | 12篇 |
1971年 | 6篇 |
1967年 | 6篇 |
排序方式: 共有1547条查询结果,搜索用时 78 毫秒
71.
M Asberg V A Ringberger F Sj?qvist P Thorén L Tr?skman J R Tuck 《Clinical pharmacology and therapeutics》1977,21(2):201-207
The effects of chlorimipramine on the concentrations of the main metabolites of serotonin (5-HT) norepinephrine (NE), and dopamine, i.e. 5-hydroxyindoleacetic acid (5-HIAA), 4-hydroxy-3-methoxyphenyl glycol (HMPG) and homovanillic acid (HVA), respectively, were studied in cerebrospinal fluid from 14 depressed patients, and related to the serotonin- and NE uptake inhibiting activity in vitro of plasma drawn from the patients. Chlorimipramine inhibited the uptake of both transmitter amines in all patients. During treatment, the levels of 5-HIAA and HMPG in cerebrospinal fluid (CSF) were significantly reduced. HVA levels were reduced in 6 patients and increased in 8 patients; there was no mean change. The decrease in 5-HIAA level in CSF was correlated to the uptake inhibition of 5-HT but there was no corresponding relationship between NE uptake and HMPG levels. The changes in HVA levels were also correlated to the uptake of 5-HT despite the absence of a unidirectional change of this metabolite. 相似文献
72.
Stephensen SS Sigfusson G Eiriksson H Sverrisson JT Torfason B Haraldsson A Helgason H 《Cardiology in the young》2004,14(4):396-401
INTRODUCTION AND BACKGROUND: About 1% of live-born children have congenital malformations of the heart. The aim of our study was to investigate the incidence of such defects in children born in Iceland during a period of 10 years, extending from 1990 through 1999. MATERIALS AND METHODS: Information about the patients was obtained from medical records from two hospitals that cover the whole country, a private clinic of pediatric cardiologists, an echocardiography database, autopsy reports, and death certificates. We investigated the distribution of specific malformations, the age at diagnosis, the symptoms leading to the diagnosis, the source of referral, and treatment and quality of life. RESULTS: Between 1990 and 1999, there were 44,013 live births in Iceland, of which 740 patients were diagnosed with congenital cardiac malformations, accounting for 1.7% of the live-born children. The distribution was made up of 338 patients with ventricular septal defect (45.7%), 90 with atrial septal defect (12.2%), 85 with patency of the arterial duct (11.5%), 48 with pulmonary valvar stenosis (6.5%), 38 with a bicuspid aortic valve (5.1%), 28 with aortic coarctation (3.8%), 22 with tetralogy of Fallot (3.0%), 14 with transposed great arteries (1.9%), 11 with aortic stenosis (1.5%), 10 with atrioventricular septal defect and common atrioventricular orifice (1.4%), 9 with mitral valvar regurgitation (1.2%), 7 with sub-aortic stenosis (0.9%), and 5 with hypoplasia of the left heart (0.7%). Extracardiac anomalies were seen in 89 patients (12.0%). Chromosomal defects were seen in 36 patients, of whom 28 had Down's syndrome. DISCUSSION: The annual incidence of diagnosis of patients with congenital cardiac malformations increased during the period of study. This was noted for minor defects, but the incidence of the major anomalies did not alter. Our observed yearly incidence, at 1.7%, was higher than noted in a previous study covering the years 1985 through 1989, and is also higher than in other population-based studies. The most likely explanation is the fact that access to pediatric cardiologists in Iceland is very good. Diagnosis, registration, and follow-up are conducted by only a few cardiologists, and take place at a single center for pediatric cardiology. 相似文献
73.
Alifrangis M Dalgaard MB Lusingu JP Vestergaard LS Staalsoe T Jensen AT Enevold A Rønn AM Khalil IF Warhurst DC Lemnge MM Theander TG Bygbjerg IC 《The Journal of infectious diseases》2006,193(12):1738-1741
Two main haplotypes, CVIET and SVMNT, of the Plasmodium falciparum chloroquine-resistance transporter gene (Pfcrt) are linked to 4-aminoquinoline resistance. The CVIET haplotype has been reported in most malaria-endemic regions, whereas the SVMNT haplotype has only been found outside Africa. We investigated Pfcrt haplotype frequencies in Korogwe District, Tanzania, in 2003 and 2004. The SVMNT haplotype was not detected in 2003 but was found in 19% of infected individuals in 2004. Amodiaquine use has increased in the region. The introduction and high prevalence of the SVMNT haplotype may reflect this and may raise concern regarding the use of amodiaquine in artemisinin-based combination therapies in Africa. 相似文献
74.
75.
Long-term results of stereotactic radiosurgery to the pituitary gland in Cushing's disease 总被引:8,自引:0,他引:8
Gamma radiation from 60Co delivered with stereotactic technique was given to the pituitary gland in 35 patients, aged 18-65 years, with Cushing's disease. The doses were 70-100 Gy in each single irradiation. The size of the sella turcica was normal in the majority of the patients. The observation time was 3-9 years in 29 patients. Out of them, 14 (48%) obtained clinical remission and normal urinary cortisol after one irradiation. Eight achieved remission after two to four irradiations. In total, 22 out of 29 patients (76%) obtained remission. In 12 of them remission was obtained in 1 year and in another 10 within 3 years. No recurrences were observed. Improvement was seen in 2 patients after one and three irradiations. Bilateral adrenalectomy was performed in 5 patients owing to unsatisfactory effect of irradiation. Pituitary insufficiency with gonadotropin, thyrotropin or corticotropin failure was demonstrated in 12 of 22 patients in remission. This occurred 4 months to 7 years after the first irradiation. Another 6 patients were followed less than 3 years after the first irradiation. Two obtained remission after the first treatment, whereas the other 4 improved. Stereotactic pituitary irradiation is suggested as a non-invasive therapeutic alternative in Cushing's disease for example in patients with considerable surgical risk or as a supplement to pituitary microsurgery. 相似文献
76.
77.
Helge Skulstad Stig Urheim Thor Edvardsen Kai Andersen Erik Lyseggen Trond Vartdal Halfdan Ihlen Otto A Smiseth 《Journal of the American College of Cardiology》2006,47(8):1672-1682
OBJECTIVES: The aim of the study was to compare the ability of the tissue Doppler echocardiographic imaging (TDI) modalities velocity, strain, and displacement to quantify systolic myocardial function. BACKGROUND: Several TDI modalities may be used to quantify regional myocardial function, but it is not clear how the different modalities should be applied. METHODS: In 10 anesthetized dogs we measured left ventricular pressure, longitudinal myocardial velocity, strain, and displacement by TDI at baseline and during left anterior descending coronary artery (LAD) stenosis and occlusion. Reference methods were segmental shortening by sonomicrometry and segmental work. In 10 patients with acute anterior wall infarction (LAD occlusion) and 15 control subjects, velocity, strain, and displacement measurements were performed. RESULTS: In the animal study, systolic strain correlated well with segmental shortening (r = 0.96, p < 0.01) and work (r = 0.90, p < 0.01), and differentiated well between non-ischemic (-13.5 +/- 3.2% [mean +/- SD]), moderately ischemic (-6.5 +/- 2.8%), and severely ischemic myocardium (7.1 +/- 13.2%). The ratio post-systolic strain/total strain also differentiated well between levels of ischemia. Displacement and ejection velocity had weaker correlations with segmental shortening (r = 0.92 and r = 0.74, respectively) and regional work (r = 0.85 and r = 0.69), and there was marked overlap between values at baseline and at different levels of ischemia. In the human study, systolic strain differentiated well between infarcted and normal myocardium (1.0 +/- 5.0% vs. -17.8 +/- 3.8%), whereas systolic displacement (-0.3 +/- 1.3 mm vs. -2.3 +/- 0.6 mm) and ejection velocity (0.9 +/- 0.6 cm/s vs. 2.2 +/- 0.6 cm/s) showed overlap. In the infarction group, strain was reduced in segments with infarcted tissue, while systolic velocity and displacement were reduced in all segments and did not reflect the extension of the infarct. CONCLUSIONS: Strain was superior to velocity and displacement for quantification of regional myocardial function. Provided technical limitations can be solved, strain Doppler is the preferred TDI modality for assessing function in ischemic myocardium. 相似文献
78.
Abstract – We present a case where a patient sustained a tympanic plate fracture of the right side while chewing a sandwich. Intense pain with temporomandibular joint (TMJ) symptoms such as restrained painful mouth opening and functional pain in full occlusion followed the incident and the fracture was diagnosed after ocular and CT-examination of the right external auditory canal. Non-ruptured soft tissue could be seen protruding into the external auditory canal and the size of the mass changed during movement of the TMJ. Treatment was not needed to resolve the situation and at 3-year follow-up the patient has no clinical symptoms. 相似文献
79.
M. Kuhlefelt P. Laine L. Suominen-Taipale T. Ingman C. Lindqvist H. Thorén 《International journal of oral and maxillofacial surgery》2010,39(5):430-435
Removal of miniplates is a controversial topic in oral and maxillofacial surgery. Originally, miniplates were designed to be removed on completion of bone healing. The introduction of low profile titanium miniplates has led to the routine removal of miniplates becoming comparatively rare in many parts of the world. Few studies have investigated the reasons for non-routine removal of miniplates and the factors that affect osteosynthesis after osteotomy in large numbers of patients. The aim of the present study was to investigate complications related to osteosynthesis after bilateral sagittal split osteotomy (BSSO) in a large number (n = 153) of patients. In addition to the rates of removal, emphasis was placed on investigating the reasons and risk factors associated with symptomatic miniplate removal. The rate of plate removal per patient was 18.6%, the corresponding rate per plate being 18.2%. Reasons for plate removal included plate-related complications in 16 patients and subjective discomfort in 13 patients. Half of the plates were removed during the first postoperative year. Smoking was the only significant predictor for plate removal. Patients undergoing orthognathic surgery should be screened with regard to smoking and encouraged and assisted to cease smoking, at least perioperatively. 相似文献
80.