全文获取类型
收费全文 | 4084篇 |
免费 | 181篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 208篇 |
妇产科学 | 52篇 |
基础医学 | 502篇 |
口腔科学 | 88篇 |
临床医学 | 288篇 |
内科学 | 736篇 |
皮肤病学 | 76篇 |
神经病学 | 278篇 |
特种医学 | 200篇 |
外科学 | 510篇 |
综合类 | 153篇 |
一般理论 | 1篇 |
预防医学 | 243篇 |
眼科学 | 209篇 |
药学 | 436篇 |
中国医学 | 24篇 |
肿瘤学 | 261篇 |
出版年
2023年 | 29篇 |
2022年 | 72篇 |
2021年 | 141篇 |
2020年 | 77篇 |
2019年 | 76篇 |
2018年 | 115篇 |
2017年 | 72篇 |
2016年 | 104篇 |
2015年 | 126篇 |
2014年 | 129篇 |
2013年 | 177篇 |
2012年 | 267篇 |
2011年 | 277篇 |
2010年 | 152篇 |
2009年 | 135篇 |
2008年 | 195篇 |
2007年 | 216篇 |
2006年 | 199篇 |
2005年 | 173篇 |
2004年 | 143篇 |
2003年 | 137篇 |
2002年 | 157篇 |
2001年 | 129篇 |
2000年 | 110篇 |
1999年 | 85篇 |
1998年 | 59篇 |
1997年 | 47篇 |
1996年 | 56篇 |
1995年 | 30篇 |
1994年 | 18篇 |
1993年 | 20篇 |
1992年 | 34篇 |
1991年 | 32篇 |
1990年 | 40篇 |
1989年 | 59篇 |
1988年 | 51篇 |
1987年 | 51篇 |
1986年 | 40篇 |
1985年 | 34篇 |
1984年 | 30篇 |
1983年 | 28篇 |
1982年 | 20篇 |
1981年 | 16篇 |
1980年 | 19篇 |
1979年 | 24篇 |
1977年 | 14篇 |
1975年 | 13篇 |
1974年 | 9篇 |
1971年 | 7篇 |
1970年 | 9篇 |
排序方式: 共有4281条查询结果,搜索用时 803 毫秒
21.
Amita Pandey Anupam Mishra 《Indian journal of otolaryngology and head and neck surgery》2007,59(4):317-321
Cytogenetics or the study of chromosomes has been an important tool in oncology. It localizes the abnormality on a particular chromosome segment as such but, the molecular analysis on the other hand focuses the exact gene of interest. Hence both are complimentary. Classical cytogenetics in combination with recent molecular techniques has given rise to various molecular cytogenetic analytical techniques such as florescent in-situ hybridization (FISH), spectral karyotyping (SKY) and comparative genomic hybridization (CGH). The role of telomeres and its concerned enzyme telomerase is important in carcinogenesis. This article summarizes the various cytogenetic techniques and presents an overall view of the importance of cytogenetcs in head and neck cancer. 相似文献
22.
Jonathan Rosman Michael Shapiro Anuragini Pandey Andrew VanTosh Steven R. Bergmann 《Journal of nuclear cardiology》2006,13(3):333-337
BACKGROUND: Coronary artery calcium (CAC) provides evidence of coronary atherosclerosis and has significant prognostic power. Although prior studies have documented a relationship between CAC and hemodynamically significant coronary artery stenosis, the results have not been conclusive. METHODS AND RESULTS: We evaluated 126 consecutive patients who underwent electron beam computed tomography CAC scoring by use of the Agatston method and stress myocardial perfusion imaging (MPI) within 3 months of each other. The analysis revealed no correlation between absolute CAC score and age- and gender-adjusted CAC scores with MPI. Overall, 18% of patients had abnormal MPI results irrespective of their CAC. CONCLUSION: CAC scoring and stress MPI should be thus considered complementary approaches rather than exclusionary in the evaluation of the patient at risk for coronary artery disease. 相似文献
23.
Entamoeba histolytica possesses significant acid phosphatase activity as compared to alkaline phosphatase activity. The acid phosphatase activity in the amoebic cells eluted at higher saline concentration as three distinct peaks at 200, 300 and 400 mM sodium chloride. 相似文献
24.
The recent Confidential Enquiry (2000-2002) has emphasised 'emergency drills for maternal resuscitation should be regularly practised in clinical areas in all maternity units'. It was therefore planned to assess the knowledge of airway management and ventilation among obstetrics and gynaecology trainees in the Yorkshire Deanery (Training Region). Questionnaires were given to trainees attending the Modular Training Programme and were collected on the same day. A total of 71 questionnaires were collected which represents 62% of the 113 trainees in Yorkshire region. Replies were received from 39 registrars, 27 Senior House Officers (SHO), four Senior SHOs (SSHO) and one clinical fellow. MRCOG Part 1 was passed by 52% and 36% of trainees had MRCOG Part 2. A total of 69% of trainees did not know that chin lift opens the airway in some 70 - 80% of patients; 50% of trainees were not aware why jaw thrust is preferred over chin lift; 76% of the trainees knew the most common cause of airway obstruction in a patient with an altered level of consciousness--the tongue falls back and obstructs the pharynx ('swallowing the tongue'). Knowledge of the main cause of airway obstruction was good among obstetrics and gynaecology trainees, but their understanding of how to manage this was found to be relatively poor. Attendance at a local Basic Life Support course should be compulsory for obstetric and gynaecology trainees early in their career. 相似文献
25.
A male patient of 60 years presented with a swelling in the left groin of 10 months duration. Past records showed bilateral
lumbar sympathectomy and omentopexy done 20 and 6 years back, respectively, for Buerger’s disease. Abdominal examination revealed
a huge hernial swelling in the left groin extending from the symphysis pubis to anterior superior iliac spine measuring 25 × 18 cm.
On exploration, the contents were intestines and omentum, which were coming out through a defect of 5 × 3 cm in the lower
fibers of the conjoint muscle 4 cm cephalad to the deep ring, a finding which made the final diagnosis as an incisional hernia.
We present this interesting case as a very rare complication of omentopexy, probably not reported previously, and an unusual
case of an incisional hernia presenting as an inguinal hernia which is very difficult to diagnose unless encountered before.
Its rarity and clinical challenge is highlighted. 相似文献
26.
Although abnormalities in serotonergic function have been the major focus of studies on suicidal behavior, several studies indicate that abnormalities of noradrenergic function may also be involved in the pathophysiology of suicide. In this paper, we have reviewed some of the noradrenergic studies in suicide, including studies of the biosynthetic enzyme for norepinephrine, tyrosine hydroxylase (TH), the receptors for norepinephrine, alpha- and beta-adrenergic receptors, as well as the signaling cascades linked to beta-adrenergic receptors. In general, these studies indicate that the protein expression of TH, as well as alpha2- and beta2-adrenergic receptors, is increased in the postmortem brain of suicide victims. More studies are needed in order to examine extensively the role of noradrenergic function in suicidal behavior. 相似文献
27.
28.
29.
N Ramamoorthy S V Shetye P M Pandey R S Mani M C Patel R B Patel P Ramanathan B A Krishna S M Sharma 《European journal of nuclear medicine》1987,12(12):623-628
Consequent to the promising results reported with 99mTc(V)-DMSA for imaging certain types of soft tissue tumors, we have developed methods to prepare this radiopharmaceutical in three ways: from freshly prepared reagents, through the use of a two component kit and use of the standard renal DMSA kit by a modified recipe. The 99mTc(V)-DMSA complex has been subjected to paper electrophoretic and chromatographic procedures and also biodistribution studies. The distinctly different behaviour of this new product compared to that of the well known renal DMSA complex has been clearly established. Scintiimaging in a preliminary clinical trial in patients with medullary carcinoma of the thyroid has been encouraging. 相似文献
30.