全文获取类型
收费全文 | 20101篇 |
免费 | 1214篇 |
国内免费 | 436篇 |
专业分类
耳鼻咽喉 | 348篇 |
儿科学 | 549篇 |
妇产科学 | 904篇 |
基础医学 | 2523篇 |
口腔科学 | 1084篇 |
临床医学 | 1880篇 |
内科学 | 1747篇 |
皮肤病学 | 126篇 |
神经病学 | 3303篇 |
特种医学 | 580篇 |
外国民族医学 | 1篇 |
外科学 | 2183篇 |
综合类 | 2541篇 |
预防医学 | 739篇 |
眼科学 | 309篇 |
药学 | 1924篇 |
5篇 | |
中国医学 | 607篇 |
肿瘤学 | 398篇 |
出版年
2024年 | 36篇 |
2023年 | 241篇 |
2022年 | 461篇 |
2021年 | 641篇 |
2020年 | 606篇 |
2019年 | 565篇 |
2018年 | 550篇 |
2017年 | 538篇 |
2016年 | 589篇 |
2015年 | 625篇 |
2014年 | 958篇 |
2013年 | 1234篇 |
2012年 | 932篇 |
2011年 | 1106篇 |
2010年 | 921篇 |
2009年 | 884篇 |
2008年 | 881篇 |
2007年 | 824篇 |
2006年 | 824篇 |
2005年 | 719篇 |
2004年 | 655篇 |
2003年 | 552篇 |
2002年 | 447篇 |
2001年 | 430篇 |
2000年 | 395篇 |
1999年 | 359篇 |
1998年 | 326篇 |
1997年 | 338篇 |
1996年 | 341篇 |
1995年 | 341篇 |
1994年 | 333篇 |
1993年 | 262篇 |
1992年 | 250篇 |
1991年 | 241篇 |
1990年 | 231篇 |
1989年 | 187篇 |
1988年 | 204篇 |
1987年 | 162篇 |
1986年 | 192篇 |
1985年 | 267篇 |
1984年 | 214篇 |
1983年 | 143篇 |
1982年 | 175篇 |
1981年 | 143篇 |
1980年 | 100篇 |
1979年 | 72篇 |
1978年 | 81篇 |
1977年 | 46篇 |
1976年 | 31篇 |
1973年 | 23篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
22.
23.
Choroid plexus papillomas (CPPs) are typically considered as benign tumors, with a favorable long-term prognosis. Drop metastasis of CPP into the spinal subarachnoid space is rare. We report a 42-year-old woman who presented with headache and back pain 6 years after removal of a posterior fossa CPP. Magnetic resonance imaging revealed mass lesions in the lumbosacral subarachnoid space and recurrent intracranial tumor. The lesions were resected and histologically diagnosed was CPP. We consider that CPP can spread via cerebrospinal fluid pathways and cause spinal drop metastasis. Therefore, it is necessary to evaluate the whole spinal axis and to perform periodic follow-up examinations in patients with CPP. 相似文献
24.
Hiroyuki ARAI 《Psychogeriatrics》2005,5(3):83-88
Alzheimer's disease (AD) generally begins with mild memory problems which occur in an insidious manner and progresses to the development of multiple cognitive impairments. There is a ‘gray’ area between what is classified as ‘normal’ and what is classified as ‘dementia’, currently called mild cognitive impairment (MCI). In this article, a case of MCI is described, and the diagnosis, assessment, subclassification (pre‐Alzheimer type and white matter lesion type) and future therapeutic plans for MCI are reviewed. 相似文献
25.
A Decision Rule for Predicting Bacterial Meningitis in Children with Cerebrospinal Fluid Pleocytosis When Gram Stain Is Negative or Unavailable 总被引:1,自引:0,他引:1
Bema K. Bonsu MBChB Henry W. Ortega MD Mario J. Marcon PhD Marvin B. Harper MD 《Academic emergency medicine》2008,15(5):437-444
Objectives: Among children with cerebrospinal fluid (CSF) pleocytosis, the task of separating aseptic from bacterial meningitis is hampered when the CSF Gram stain result is unavailable, delayed, or negative. In this study, the authors derive and validate a clinical decision rule for use in this setting.
Methods: This was a review of peripheral blood and CSF test results from 78 children (<19 years) presenting to Children's Hospital Columbus from 1998 to 2002. For those with a CSF leukocyte count of >7/μL, a rule was created for separating bacterial from viral meningitis that was based on routine laboratory tests, but excluded Gram stain. The rule was validated in 158 subjects seen at the same site (Columbus, 2002–2004) and in 871 subjects selected from a separate site (Boston, 1993–1999).
Results: One point each (maximum, 6 points) was assigned for leukocytes >597/μL, neutrophils >74%, glucose <38 mg/dL, and protein >97 mg/dL in CSF and for leukocytes >17,000/mL and bands to neutrophils >11% in peripheral blood. Areas under receiver-operator-characteristic curves (AROCs) for the resultant score were 0.98 for the derivation set and 0.90 and 0.97, respectively, for validation sets from Columbus and Boston. Sensitivity and specificity pairs for the Boston data set were 100 and 44%, respectively, at a score of 0 and 97 and 81% at a score of 1. Likelihood ratios (LRs) increased from 0 at a score of 0 to 40 at a score of ≥4.
Conclusions: Among children with CSF pleocytosis, a prediction score based on common tests of CSF and peripheral blood and intended for children with unavailable, negative, or delayed CSF Gram stain results has value for diagnosing bacterial meningitis. 相似文献
Methods: This was a review of peripheral blood and CSF test results from 78 children (<19 years) presenting to Children's Hospital Columbus from 1998 to 2002. For those with a CSF leukocyte count of >7/μL, a rule was created for separating bacterial from viral meningitis that was based on routine laboratory tests, but excluded Gram stain. The rule was validated in 158 subjects seen at the same site (Columbus, 2002–2004) and in 871 subjects selected from a separate site (Boston, 1993–1999).
Results: One point each (maximum, 6 points) was assigned for leukocytes >597/μL, neutrophils >74%, glucose <38 mg/dL, and protein >97 mg/dL in CSF and for leukocytes >17,000/mL and bands to neutrophils >11% in peripheral blood. Areas under receiver-operator-characteristic curves (AROCs) for the resultant score were 0.98 for the derivation set and 0.90 and 0.97, respectively, for validation sets from Columbus and Boston. Sensitivity and specificity pairs for the Boston data set were 100 and 44%, respectively, at a score of 0 and 97 and 81% at a score of 1. Likelihood ratios (LRs) increased from 0 at a score of 0 to 40 at a score of ≥4.
Conclusions: Among children with CSF pleocytosis, a prediction score based on common tests of CSF and peripheral blood and intended for children with unavailable, negative, or delayed CSF Gram stain results has value for diagnosing bacterial meningitis. 相似文献
26.
27.
Tass H Malik Iain A Bruce Gerard Kelly Richard T Ramsden Shakeel R Saeed 《Skull base》2007,17(4):235-238
In cases of cerebrospinal fluid (CSF) rhinorrhea following lateral skull base surgery, fibrosis and fibrin formation resulting from meningitis has been postulated as a mechanism of spontaneously resolving the CSF leak. This study was undertaken to explore any possible relationship between the cessation of CSF leak and meningitis. A retrospective study at a tertiary referral center of 232 consecutive patients was performed. Out of a total of 232 procedures, 29 patients developed CSF rhinorrhea, of whom 7 subsequently developed meningitis. Bacteria were isolated in CSF obtained at lumbar puncture in 5 cases, with the CSF analysis in the remaining 2 cases suggesting aseptic meningitis. Conservative treatment failed to stop the CSF rhinorrhea in 6 of 7 cases. In this study, the development of meningitis did not appear to aid in the resolution of the CSF rhinorrhea. We conclude that surgical intervention should not be delayed in the expectation that meningitis and conservative interventions may promote CSF leak resolution. 相似文献
28.
Cerebrospinal fluid and plasma concentrations of oxytocin and vasopressin during parturition and vaginocervical stimulation in the sheep 总被引:1,自引:0,他引:1
Simultaneous blood and cerebrospinal fluid (CSF) samples were taken from conscious sheep before, during and after parturition. Concentrations of plasma and CSF oxytocin were significantly elevated during contractions and particularly at birth. Mean prepartum CSF concentrations of oxytocin were around 55% of those found in plasma but postpartum they were up to 2-fold higher than those in plasma. Plasma concentrations of oxytocin were only significantly elevated, compared to prepartum levels, for 15 min postpartum whereas those in CSF were increased for the whole of the 120 min postpartum sampling period. Plasma, but not CSF, concentrations of arginine-vasopressin (AVP) were significantly raised during contractions and birth, and for 15 min postpartum. During the prepartum period CSF AVP concentrations were 67% of those found in plasma whereas at birth plasma levels were 10-fold higher than in CSF. In a separate experiment it was shown that 5 min of mechanical vaginocervical stimulation also stimulated significant increases in CSF and plasma oxytocin concentrations and in plasma vasopressin. Results support previous work suggesting an important role for central oxytocin release in the postpartum induction of maternal behavior and demonstrate that elevated concentrations of oxytocin in the CSF are present for a greater period than in blood. Elevated plasma AVP concentrations during contractions, birth or vaginocervical stimulation may be stimulated by stress associated with these stimuli. 相似文献
29.
High levels of the soluble form of CD30 molecule in rheumatoid arthritis (RA) are expression of CD30+ T cell involvement in the inflamed joints. 总被引:2,自引:0,他引:2
下载免费PDF全文
![点击此处可从《Clinical and experimental immunology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
R Gerli C Muscat O Bistoni B Falini C Tomassini E Agea R Tognellini P Biagini A Bertotto 《Clinical and experimental immunology》1995,102(3):547-550
The CD30 is a surface molecule expressed by Th2-type lymphokine-producing T cells upon activation. CD30-expressing activated T cells release a soluble form of the molecule, which can be detectable both in vitro and in vivo. In the present study, high levels of soluble CD30 were found in peripheral blood and synovial fluid from patients with RA. However, CD30+ CD3+ cells, either CD4+ or CD8+, were significantly present in synovial fluid, but not in peripheral blood, of RA patients. Serum values of soluble CD30 were higher in active than inactive RA patients and directly correlated with rheumatoid factor serum titres. These data strongly support an involvement of CD30+ T cells in the immune processes of rheumatoid synovitis, and may suggest a relationship between Th2-type cytokine-secreting T cells and the pathological response in RA. 相似文献
30.
E. Weimann G. Reisbach J. Reinsberg M. J. Lentze 《Archives of gynecology and obstetrics》1995,256(3):125-130
Activity levels of cytokines were measured by stimulation of the cell lines NFS-60, 7TD1, and TF-1. In 39 samples of amniotic fluid, levels of Granulocyte-Stimulating Factor (G-CSF) were 1434±2063 (mean±SD) and of Interleukin (IL-6) 546±1071 pg/ml; Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF) was not detectable. IL-6 was correlated to G-CSF (r=0.3; p=0.003). G-CSF (p=0.0002) and IL-6 (p=0.006) were influenced by Alpha-Fetoprotein (AFP) and G-CSF by rhesus-incompatibility (p=0.0004). These findings suggest that cytokines such as IL-6 and G-CSF play some role in physiological and pathological pregnancy.Abbreviations G-CSF
granulocyte-colony stimulating factor
- GM-CSF
granulocyte-macrophage colony stimulating factor
- M-CSF
macrophage-colony stimulating factor
- CSF
colonystimulating factor
- IL-6
interleukin-6
- IL-11
interleukin-11
- AFP
alpha-fetoprotein
- NFS-60
cell line
- 7TD1
cell line
- TF-l
cell line
- rh
recombinant human
- MTT
3-(4,5-dimethylthiazol2-yl)-2,5-diphenyl tetrazolium bromide
- FCS
fetal calf serum
- RPMI 1640
nutrient solution
- ATCC
American Tissue Culture Collection
Correspondence to: E. Weimann 相似文献