全文获取类型
收费全文 | 185篇 |
免费 | 4篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 4篇 |
妇产科学 | 23篇 |
基础医学 | 14篇 |
口腔科学 | 7篇 |
临床医学 | 21篇 |
内科学 | 23篇 |
皮肤病学 | 8篇 |
神经病学 | 2篇 |
特种医学 | 47篇 |
外科学 | 13篇 |
综合类 | 1篇 |
预防医学 | 6篇 |
药学 | 18篇 |
肿瘤学 | 13篇 |
出版年
2023年 | 1篇 |
2020年 | 1篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2016年 | 1篇 |
2015年 | 1篇 |
2014年 | 5篇 |
2013年 | 12篇 |
2012年 | 2篇 |
2011年 | 5篇 |
2010年 | 9篇 |
2009年 | 10篇 |
2008年 | 4篇 |
2007年 | 18篇 |
2006年 | 6篇 |
2005年 | 8篇 |
2004年 | 4篇 |
2002年 | 3篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 11篇 |
1997年 | 12篇 |
1996年 | 5篇 |
1995年 | 7篇 |
1994年 | 3篇 |
1993年 | 7篇 |
1992年 | 6篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 4篇 |
1988年 | 5篇 |
1987年 | 6篇 |
1986年 | 5篇 |
1985年 | 1篇 |
1984年 | 5篇 |
1983年 | 3篇 |
1982年 | 6篇 |
1981年 | 1篇 |
1980年 | 5篇 |
1979年 | 1篇 |
1977年 | 3篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1971年 | 1篇 |
排序方式: 共有202条查询结果,搜索用时 0 毫秒
81.
Comparison of respiratory triggering and gating techniques for the removal of respiratory artifacts in MR imaging 总被引:1,自引:0,他引:1
Respiratory movement degrades magnetic resonance (MR) images of the chest and abdomen by increasing noise through the production of "ghost" artifacts and by decreasing edge sharpness in moving structures. Respiratory gating, which limits data acquisition to end-expiration, is successful in restoring edge sharpness and reducing ghosts but increases imaging time two to three times, which limits its use to sequences with short repetition times (TRs). To overcome this limitation, an alternative technique, respiratory triggering, was developed, which triggers the acquisition of an MR section at a fixed point on the respiratory cycle. This technique restores edge sharpness and reduces ghosts, but unlike gating, it can be used to produce an image at any phase of the respiratory cycle. Triggering requires long TRs since the TR is limited to the respiratory period (TP) or one-half of TP, depending on whether the same section is triggered once or twice during a single respiratory cycle. Gating and triggering were evaluated and compared for single-section and multi-section imaging of both volunteers and patients. The authors conclude that when a chest or abdominal survey is required, triggering takes less time than gating if TRs are required that exceed one-fifth of TP. 相似文献
82.
High expression of Lewis<Superscript>y/b</Superscript>antigens is associated with decreased survival in lymph node negative breast carcinomas 总被引:1,自引:0,他引:1 下载免费PDF全文
Madjd Z Parsons T Watson NF Spendlove I Ellis I Durrant LG 《Breast cancer research : BCR》2005,7(5):R780-R787
Introduction
There is sufficient evidence that blood group related Lewis antigens are tumour-associated molecules. The Lewisy and Lewisb antigens are complex carbohydrates that are over-expressed by breast, lung, colon and ovarian cancers. The SC101 mAb is a unique Lewisy/b binding antibody that binds to native and extended Lewisy and Lewisb haptens, displaying no cross reactivity with H type 1, H type 2, Lewisx or normal blood group antigens. 相似文献83.
Subacute and chronic bone infections: diagnosis using In-111, Ga-67 and Tc-99m MDP bone scintigraphy, and radiography 总被引:3,自引:0,他引:3
Al-Sheikh W; Sfakianakis GN; Mnaymneh W; Hourani M; Heal A; Duncan RC; Burnett A; Ashkar FS; Serafini AN 《Radiology》1985,155(2):501-506
The usefulness of indium-111 white blood cell scintigraphy in the diagnosis of subacute or chronic bone infection was examined in 21 orthopedic patients. In-111 WBC imaging was compared with gallium-67 and technetium-99m methylene diphosphonate skeletal scintigraphy and bone radiography, all studies being performed within 1 week. In-111 WBC scintigraphy showed no definite advantage over Ga-67 scintigraphy in the identification of chronic bone infection. The two tests had the same sensitivity (80%) and similar specificity (In-111 WBC 75%, Ga-67 83%; difference not significant). Bone radiography had a sensitivity of 60% and a specificity of 67%. A negative Tc-99m MDP bone scintigram ruled out infection (sensitivity 100%), but because of low specificity (25%), final evaluation required performance of Ga-67 or In-111 WBC scintigraphy. 相似文献
84.
Aagaard-Tillery KM Nuthalapaty FS Ramsey PS Ramin KD 《American journal of perinatology》2005,22(6):287-297
Preterm premature rupture of the membranes (PPROM) occurs in approximately 3% of all pregnancies, and accounts for one third of all preterm births. Despite its prevalence, optimal management of PPROM remains largely undefined and lacks conformity. In this article, we review the pathophysiology of PPROM, and summarize the available literature describing various management strategies in an effort to define current controversies in the management of PPROM. 相似文献
85.
86.
87.
Brady TJ; Goldman MR; Pykett IL; Buonanno FS; Kistler JP; Newhouse JH; Burt CT; Hinshaw WS; Pohost GM 《Radiology》1982,144(2):343-347
In a study to evaluate the potential of proton nuclear magnetic resonance (NMR) imaging with and without manganese contrast with and without manganese contrast enhancement for detecting acute myocardial infarction, 12 dogs underwent 90-minute occlusion of the left circumflex coronary artery. Transverse-section NMR images of the excised, nonbeating heart were obtained at 1-cm intervals using the steady-state-free-precession (SSFP) technique. All NMR images revealed detailed structure of the heart. The three hearts without manganese showed no difference in intensity between the normal and the ischemic posterior regions, whereas those with manganese demonstrated a clearly demarcated zone of reduced signal intensity consistent with the ischemic zone. It is concluded that high-resolution tomograms of the excised canine myocardium can be obtained using proton NMR imaging. With the SSFP imaging technique, proton signal enhancement with manganese infusion is necessary to differentiate between ischemic and nonischemic myocardium after 90 minutes of coronary occlusion. 相似文献
88.
89.
Germline mutations of the MEN1 gene in familial multiple endocrine neoplasia type 1 and related states 总被引:9,自引:0,他引:9
Agarwal SK; Kester MB; Debelenko LV; Heppner C; Emmert-Buck MR; Skarulis MC; Doppman JL; Kim YS; Lubensky IA; Zhuang Z; Green JS; Guru SC; Manickam P; Olufemi SE; Liotta LA; Chandrasekharappa SC; Collins FS; Spiegel AM; Burns AL; Marx SJ 《Human molecular genetics》1997,6(7):1169-1175
Familial multiple endocrine neoplasia type 1 (FMEN1) is an autosomal
dominant trait characterized by tumors of the parathyroids, gastro-
intestinal endocrine tissue, anterior pituitary and other tissues. We
recently cloned the MEN1 gene and confirmed its identity by finding
mutations in FMEN1. We have now extended our mutation analysis to 34 more
unrelated FMEN1 probands and to two related states, sporadic MEN1 and
familial hyperparathyroidism. There was a high prevalence of heterozygous
germline MEN1 mutations in sporadic MEN1 (8/11 cases) and in FMEN1 (47/50
probands). One case of sporadic MEN1 was proven to be a new MEN1 mutation.
Eight different mutations were observed more than once in FMEN1. Forty
different mutations (32 FMEN1 and eight sporadic MEN1) were distributed
across the MEN1 gene. Most predicted loss of function of the encoded menin
protein, supporting the prediction that MEN1 is a tumor suppressor gene. No
MEN1 germline mutation was found in five probands with familial
hyperparathyroidism, suggesting that familial hyperparathyroidism often is
caused by mutation in another gene or gene(s).
相似文献
90.