全文获取类型
收费全文 | 11840篇 |
免费 | 1303篇 |
国内免费 | 48篇 |
专业分类
耳鼻咽喉 | 62篇 |
儿科学 | 306篇 |
妇产科学 | 397篇 |
基础医学 | 1557篇 |
口腔科学 | 225篇 |
临床医学 | 1704篇 |
内科学 | 2622篇 |
皮肤病学 | 160篇 |
神经病学 | 1339篇 |
特种医学 | 515篇 |
外科学 | 1230篇 |
综合类 | 224篇 |
一般理论 | 11篇 |
预防医学 | 1185篇 |
眼科学 | 164篇 |
药学 | 701篇 |
肿瘤学 | 789篇 |
出版年
2021年 | 121篇 |
2020年 | 115篇 |
2019年 | 147篇 |
2018年 | 180篇 |
2017年 | 154篇 |
2016年 | 169篇 |
2015年 | 214篇 |
2014年 | 284篇 |
2013年 | 400篇 |
2012年 | 534篇 |
2011年 | 512篇 |
2010年 | 321篇 |
2009年 | 310篇 |
2008年 | 566篇 |
2007年 | 535篇 |
2006年 | 488篇 |
2005年 | 494篇 |
2004年 | 420篇 |
2003年 | 373篇 |
2002年 | 334篇 |
2001年 | 345篇 |
2000年 | 392篇 |
1999年 | 343篇 |
1998年 | 226篇 |
1997年 | 207篇 |
1996年 | 214篇 |
1995年 | 168篇 |
1994年 | 137篇 |
1993年 | 146篇 |
1992年 | 269篇 |
1991年 | 295篇 |
1990年 | 269篇 |
1989年 | 250篇 |
1988年 | 231篇 |
1987年 | 229篇 |
1986年 | 251篇 |
1985年 | 233篇 |
1984年 | 175篇 |
1983年 | 154篇 |
1982年 | 112篇 |
1981年 | 93篇 |
1980年 | 97篇 |
1979年 | 175篇 |
1978年 | 106篇 |
1977年 | 92篇 |
1975年 | 95篇 |
1974年 | 102篇 |
1973年 | 102篇 |
1972年 | 93篇 |
1971年 | 94篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
Biophysical and biological activity of a synthetic 8.7-kDa hydrophobic pulmonary surfactant protein SP-B. 总被引:5,自引:1,他引:4 下载免费PDF全文
V K Sarin S Gupta T K Leung V E Taylor B L Ohning J A Whitsett J L Fox 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(7):2633-2637
We have synthesized pulmonary surfactant apoprotein SP-B peptides by solid-phase chemistry and demonstrated their ability to enhance the surface-active properties of synthetic lipid mixtures. The synthetic peptides were reactive with antiserum generated against the native bovine surfactant peptide. Both peptides conferred surfactant-like properties to synthetic lipid mixtures as assessed by a Wilhelmy balance and pulsating bubble surfactometer. Likewise, mixtures of synthetic SP-B peptides and lipid restored compliance of isolated surfactant-deficient rat lungs. This work demonstrates the utility of SP-B as a functional component of pulmonary surfactant mixtures for treatment of respiratory distress syndrome or other disorders characterized by surfactant deficiency. 相似文献
992.
K A Louden F Broughton Pipkin S Heptinstall S C Fox J R Mitchell E M Symonds 《British journal of obstetrics and gynaecology》1990,97(12):1108-1114
A longitudinal study of platelet behaviour (platelet aggregation and release reaction) in whole blood and of serum thromboxane B2 production was performed before, during and after normal pregnancy. The response of platelets to arachidonic acid and to adrenaline was significantly increased in the third trimester. Six weeks after delivery, values were still modestly increased but return to non-pregnant values was complete by 12 weeks. Serum thromboxane B2 production was unchanged throughout pregnancy and the puerperium. 相似文献
993.
The scars of newborn intensive care 总被引:2,自引:0,他引:2
Many techniques used in neonatal intensive care are invasive and the risk of producing skin damage is high. To investigate this, 100 consecutive survivors of neonatal intensive care (gestation 26-42 weeks, median 32) were examined in detail by a single observer at 16-29 months of age, and the scar severity, site and likely cause noted. Scarring was present in all infants although it was usually trivial. The total number of scars was inversely related to gestational age and directly related to the duration of intensive care. Eleven children had cosmetically or functionally significant lesions caused by chest drain insertion, extravasation of intravenous fluid or skin stripping by adhesive tape. To reduce the frequency and severity of skin damage, neonatal staff need to be aware that many routine procedures may lead to long term scarring. In particular, more careful wound closure after chest drain removal is needed. 相似文献
994.
M G Dunlop J N Fox P A Stonebridge A E Clason C V Ruckley 《The British journal of surgery》1990,77(5):562-563
A pilot study of 100 consecutive groin wounds after vascular surgery demonstrated lymph leaks in 12 per cent. Lymph leak was significantly associated with wound infection and with prolongation of in-patient stay. A controlled trial was therefore instituted to assess the influence of vacuum drainage in groin wound healing. One hundred and twenty-seven wounds were randomized to drainage (n = 65) or no drainage (n = 62) and the wounds were examined 'blind' by independent observers. No difference in the incidence of lymph leakage or wound infection was noted between the two groups. The routine use of suction drainage for groin wounds in vascular surgery is unnecessary. 相似文献
995.
996.
Trevor Andrews Jack L Lancaster Stephen J Dodd Carmen Contreras-Sesvold Peter T Fox 《Magnetic resonance in medicine》2005,54(2):449-454
A three-pool model was used to improve white-matter T2 relaxometry in low signal-to-noise (SNR) data. To verify the model very high SNR T2 relaxometry experiments were performed on myelinated tissue samples and three-pool fractions were consistently found. Relaxation curves based on the in vitro results were simulated with multiple SNRs and fit using the three-pool model and three less constraining nonnegative least squares-based methods. All methods performed well with noiseless data. At lower SNR values the three-pool model was superior, primarily due to the fact that the other methods often could not unambiguously calculate pool fractions. 相似文献
997.
Susie M.D. Henley PhD Edward J. Wild MRCP Nicola Z. Hobbs MEng Chris Frost DipStat David G. MacManus MSc Roger A. Barker PhD Nick C. Fox PhD Sarah J. Tabrizi PhD 《Movement disorders》2009,24(6):932-936
Therapeutic trials in Huntington's disease (HD) are challenging as clinical progression is slow and variable and reliable biomarkers are lacking. We used magnetic resonance imaging and the brain boundary shift integral to quantify whole‐brain atrophy rates over 1 year in early and premanifest HD subjects, and controls. Early HD subjects had statistically significantly (P = 0.007) increased (threefold higher) rates of whole‐brain atrophy compared with controls. Higher atrophy rates were associated with longer CAG repeat length. MRI‐based measures of whole‐brain atrophy may have potential as a measure of progression in HD. © 2009 Movement Disorder Society 相似文献
998.
999.
1000.
Tear and serum antibody levels in ocular herpetic infection: diagnostic precision of secretory IgA. 总被引:4,自引:1,他引:3 下载免费PDF全文
P D Fox P T Khaw B W McBride J I McGill K A Ward 《The British journal of ophthalmology》1986,70(8):584-588
A sensitive enzyme linked immunosorbent assay (ELISA) was developed to evaluate the potential of herpes simplex virus (HSV) specific antibodies in the diagnosis of herpetic eye infection. The presence of HSV specific secretory IgA (sIgA) in tears was found to be diagnostic of infection. However, serum and tear HSV specific IgG and IgA were not considered reliable indicators of active infection. 相似文献