全文获取类型
收费全文 | 40171篇 |
免费 | 3315篇 |
国内免费 | 991篇 |
专业分类
耳鼻咽喉 | 1870篇 |
儿科学 | 834篇 |
妇产科学 | 399篇 |
基础医学 | 3021篇 |
口腔科学 | 525篇 |
临床医学 | 5802篇 |
内科学 | 5366篇 |
皮肤病学 | 449篇 |
神经病学 | 2184篇 |
特种医学 | 1599篇 |
外国民族医学 | 6篇 |
外科学 | 2251篇 |
综合类 | 6473篇 |
现状与发展 | 5篇 |
一般理论 | 5篇 |
预防医学 | 4792篇 |
眼科学 | 481篇 |
药学 | 3330篇 |
55篇 | |
中国医学 | 3453篇 |
肿瘤学 | 1577篇 |
出版年
2024年 | 151篇 |
2023年 | 835篇 |
2022年 | 1425篇 |
2021年 | 2075篇 |
2020年 | 1931篇 |
2019年 | 1657篇 |
2018年 | 1739篇 |
2017年 | 1577篇 |
2016年 | 1741篇 |
2015年 | 1537篇 |
2014年 | 3070篇 |
2013年 | 2988篇 |
2012年 | 2702篇 |
2011年 | 2646篇 |
2010年 | 2146篇 |
2009年 | 1825篇 |
2008年 | 1759篇 |
2007年 | 1829篇 |
2006年 | 1532篇 |
2005年 | 1259篇 |
2004年 | 1068篇 |
2003年 | 1025篇 |
2002年 | 702篇 |
2001年 | 697篇 |
2000年 | 541篇 |
1999年 | 511篇 |
1998年 | 367篇 |
1997年 | 345篇 |
1996年 | 305篇 |
1995年 | 283篇 |
1994年 | 293篇 |
1993年 | 193篇 |
1992年 | 170篇 |
1991年 | 132篇 |
1990年 | 150篇 |
1989年 | 115篇 |
1988年 | 108篇 |
1987年 | 96篇 |
1986年 | 74篇 |
1985年 | 147篇 |
1984年 | 130篇 |
1983年 | 103篇 |
1982年 | 122篇 |
1981年 | 68篇 |
1980年 | 82篇 |
1979年 | 43篇 |
1978年 | 55篇 |
1977年 | 27篇 |
1976年 | 24篇 |
1975年 | 16篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
32.
Serum IgA and IgG functional antibodies and their subclasses to Streptococcus pneumoniae capsular antigen found in two aged‐matched cohorts of children with and without otitis media with effusion The relationship between acute otitis media and otitis media with effusion (OME) is uncertain and the aetiology of OME is multifactorial. Otitis media with effusion may be an inflammatory condition; both bacteria and viral infections could play a part in this inflammation. The four bacteria Streptococcus pneumoniae, Haemophilus influenza, Staphylococcus aureus and Branhamella catarrhalis cause 60% of the infections whereas S. pneumoniae accounts for up to 35%. IgA provides the dominant surface response to polysaccharide and lipopolysaccharide antigens, of which IgA2 is the main subclass. Once the mucosa has been breached, most protection is provided by IgG. IgG2 acts mainly against bacterial capsular antigens. This study looked at two groups of 50 children with and without OME who were aged between 3 and 10 years. The aims were to determine if, firstly, the levels of the serum immunoglobulins were different in the two groups, secondly whether these children made the appropriate antibody response to the capsular antigen to S. pneumoniae (PCP), and finally if there was a delay in the maturity of the IgA response. The total IgG, IgA and all subclass levels were measured using radial immunodiffusion. Levels of functional IgA and IgG were measured using ELISAs (25 patients in each group). The results were analysed with non‐parametric tests. The immunoglobulin levels were within the normal levels for both groups. There were very good correlations between the IgG total anti‐PCP and the IgG2 anti‐PCP (R > 0.9, p = 0.001). There was a good correlation between the levels of both IgG total and IgG2 anti‐PCP against IgA total anti‐PCP in both groups (R > 0.85, p > 0.01). This confirms a normal antibody response between both groups of patients. The ages of the controls and patients (50 samples) were correlated with increasing titres of circulating functional antibodies (P = 0.001). This is highly suggestive of a normal age‐related response. In conclusion, the findings were contradictory to our original hypothesis that there is a subtle difference in surface protection between children with and without OME. We believe that a previous history of recurrent acute otitis media is unrelated to the development of OME after 3 years of age. 相似文献
33.
Marisa Klein-Gitelman 《Clinical and Applied Immunology Reviews》2004,4(5):333-350
Systemic lupus erythematosus (SLE) is the archetypical immunologic disease. Approximately 20% of patients present in the first two decades of life. This article highlights some of the differences between pediatric and adult onset lupus.Children are defined as different from adults on the basis of age. Lupus presents with different gender ratios based on hormonal or pubertal status with more significant skewing toward female patients in the childbearing years. Female patients in the childbearing years appear to have a higher relative risk for mortality. Despite this, children have greater disease severity at onset based on the number of patients who present with significant organ inflammation, the amount of corticosteroids required and the abnormalities in lupus serologies including autoantibodies and low complements. Children present frequently with congenital and acquired complement defects. Children have an increased risk of infections that can be confused with lupus. They have a higher risk of serious pneumococcal infection and may have less protection from vaccinations received at the time of disease onset.The clinical immunology laboratory is critical in the diagnosis and treatment of pediatric SLE. The rapid analysis and transfer of laboratory results can be life saving for the child with suspected new onset lupus. The laboratory is also helpful in determining disease activity through analysis of immunologic trends over time in pediatric lupus patients. This is especially important in the noncompliant adolescent patient who has a correlation between disease activity and lupus serologic tests. Finally, the clinical immunology laboratory is an important tool for better understanding of the immunologic phenomena associated with lupus and of disease pathophysiology. 相似文献
34.
网络教育资源构建中Windows Media流媒体技术的应用与研究 总被引:1,自引:0,他引:1
Windows Media流媒体由于交互性强、使用方便和效率高,使得在网络教育中的应用逐渐增多。本文讨论了Windows Media流媒体技术在网络教育和资源构建中应用的优势及其在设计、制作、发布、应用等各环节的相关理论和技术细节。 相似文献
35.
We present a patient who developed a painful third nerve galsy two days after angiography had demonstrated a large aneurysm on the P1 segment of the left posterior cerebral artery. CT at this stage demonstrated extensive thrombus within the previously uncomplicated aneurysm. The haemodynamics of this aneurysm resulted in incomplete clearance of contrast medium from its fundus and we posit that this may have promoted thrombus formation. Six months later the aneurysm was shown angiographically to be completely occluded. 相似文献
36.
37.
NISHAN GOUDSOUZIAN 《Paediatric anaesthesia》1997,7(3):183-190
Mivacurium is the only available short-acting nondepolarizing muscle relaxant in clinical use. It is a bis-quaternary benzylisoquinolinium ester hydrolysed by plasma-cholinesterase into inactive compounds. The ED50 and ED95 in children are about 50 μg·kg?1 and 90 μg·kg?1 respectively. In infants, they have a tendency to be lower. A standard intubating dose of 0.25 mg·kg?1 causes complete neuromuscular depression in 1.5–2 min, recovery to 5% in 6–10 min, and complete recovery in 15–20 min. The recent tendency is to use 0.3 mg·kg?1 to obtain better intubating conditions with slight prolongation of effect. Since the recovery profile of mivacurium is independent of the dose and duration, it is most suitable for administration by continuous infusion. The infusion requirement in children is 10–16 μg·kg?1 min?1, which is about twice that of adults. Cutaneous flushes from histamine release are commonly seen with the larger doses of mivacurium; however, the associated hypotensive effects are minimal and counteracted by the tracheal intubation. The duration of action of mivacurium is prolonged in patients with cholinesterase deficiency. Mivacurium's neuromuscular effects can be satisfactorily antagonized by edrophonium or neostigmine. 相似文献
38.
谢林 《湖南中医药大学学报》1994,14(2):1-3
本文从髌骨软骨软化症的病因病理出发,阐述了活血化瘀疗法治疗髌骨软骨软化症的作用及其原理,列举了活血化瘀法在该病治疗中的具体运用,同时强调了在辨证施治基础上活血化瘀的重要性。 相似文献
39.
HemorrhagicfeverwithrenalsyndromevirusinfectioninliversstudiedbyinsituhybridizationandimmunohistochemistryYangShoujing(杨守京);L... 相似文献
40.
本文应用“冷沉淀”法制备纤维组织粘合剂。对纤维组织粘合剂中主要成份和含量进行了测定,并测定了主要理化性质,建立了动物实验模型,观察了实验兔对纤维粘合剂的反应。 相似文献