全文获取类型
收费全文 | 262篇 |
免费 | 7篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 1篇 |
基础医学 | 3篇 |
口腔科学 | 1篇 |
临床医学 | 33篇 |
内科学 | 25篇 |
特种医学 | 129篇 |
外科学 | 29篇 |
综合类 | 23篇 |
预防医学 | 1篇 |
药学 | 2篇 |
肿瘤学 | 10篇 |
出版年
2022年 | 5篇 |
2021年 | 2篇 |
2020年 | 5篇 |
2019年 | 2篇 |
2018年 | 5篇 |
2017年 | 3篇 |
2016年 | 8篇 |
2015年 | 4篇 |
2014年 | 5篇 |
2013年 | 4篇 |
2012年 | 5篇 |
2011年 | 5篇 |
2010年 | 9篇 |
2009年 | 11篇 |
2008年 | 8篇 |
2007年 | 9篇 |
2006年 | 18篇 |
2005年 | 11篇 |
2004年 | 11篇 |
2003年 | 18篇 |
2002年 | 12篇 |
2001年 | 15篇 |
2000年 | 18篇 |
1999年 | 11篇 |
1998年 | 12篇 |
1997年 | 21篇 |
1996年 | 10篇 |
1995年 | 10篇 |
1994年 | 12篇 |
1993年 | 2篇 |
1992年 | 2篇 |
排序方式: 共有273条查询结果,搜索用时 31 毫秒
1.
YY Ho 《Journal of Medical Imaging and Radiation Oncology》2005,49(6):445-459
Bone and soft tissue tumours are rare neoplasms. There are five major roles of imaging in the management of primary musculoskeletal tumours, that is, to differentiate between benignity and malignancy, to evaluate for local tumour extension, to screen for metastases, to judge the effect of chemotherapy, and to monitor for recurrence. To accomplish this, multiple modalities are required because no single examination is able to complete all these tasks. These modalities include plain radiography, CT, MRI, conventional nuclear medicine as well as positron emission tomography (PET) imaging. Elsewhere, PET imaging has been discussed at length, because it is likely to be superior in the assessment of bone and soft tissue tumours over conventional nuclear medicine procedures. However, conventional nuclear medicine may be of value when PET is unavailable. In this review, an overview of anatomical imaging will be given and the role of non‐PET functional imaging will be discussed in detail. A variety of illustrative cases will be presented. 相似文献
2.
László Bajnok Bertalan Kozlovszky József Varga Judit Antalffy Sándor Olvasztó Tamás Fülöp Jr. 《European journal of nuclear medicine and molecular imaging》1994,21(12):1326-1332
Technetium-99m sestamibi was used for functional investigation of the muscle perfusion of lower extremities in 35 patients
with peripheral vascular disease. The aim was to test what useful information could be obtained by additional imaging of the
legs in patients referred for risk stratification with dipyridamole myocardial scanning. Posterior images were acquired over
the thighs and calves after postocclusive reactive hyperaemia and at rest. Inter- and intraextremity ratios and differences
between the stress and rest data were used for the assessment of abnormal circulation. Arteriography was performed in every
case, and surgical procedures or transluminal angioplasty in 31 patients. To estimate diagnostic accuracy, the results of99mTc-sestamibi scintigraphy were compared with those of angiography and the functional consequences of revascularization procedures.
The sensitivity and specificity of99mTc-sestamibi scintigraphy were 55% and 25%, respectively, with an overall accuracy of 50%. Apparently methodological error
was not responsible for these poor results. Instead, a paradoxically high uptake of the radiopharmaceutical in muscles supplied
by significantly stenosed vessels was identified as the main source of both false-negative and false-positive results. This
phenomenon resembles the findings of a previous study involving delayed administration of thallium-201 after exercise. In
conclusion,99mTc-sestamibi scintigraphy has not proved sufficiently reliable to help in the management strategy for patients with peripheral
vascular disease. 相似文献
3.
Review of imaging techniques for the diagnosis of breast cancer: a new role of prone scintimammography using technetium-99m sestamibi 总被引:6,自引:4,他引:2
Iraj Khalkhali Ismael Mena Linda Diggles 《European journal of nuclear medicine and molecular imaging》1994,21(4):357-362
Imaging techniques currently used for the diagnosis of breast cancer are reviewed and compared. Besides mammography, magnetic resonance imaging, positron emission tomography, and thallium-201 scintimammography, a new role of technetium-99m sestamibi scintimammography is discussed. It is concluded that while mammography remains the procedure of choice in screening asymptomatic women for breast cancer, other imaging methods play an important role in detecting malignancies in symptomatic patients.99mTc-sestamibi scintimammography has high sensitivity and improves the specificity of conventional mammography for the detection of breast cancer; with this technique, prone imaging is preferable to supine imaging.99mTc-sestamibi scintimammography thus deserves further study as a screening technique. 相似文献
4.
Marc J. Claeys Frank E. Rademakers Chris J. Vrints Bruno Krug Johan M. Bosmans Viviane Conraads Leo L. Bossaert Jo P. Snoeck Pierre P. Blockx 《European journal of nuclear medicine and molecular imaging》1996,23(7):748-755
Rest technetium-99m sestamibi single-photon emission tomography (SPET) has been shown to under-estimate viability in some patients with chronic ischaemic myocardial dysfunction. The present study was designed to appraise the value of99mTc-sestamibi as a viability tracer in patients with a recent myocardial infarction and to determine factors that might influence its accuracy in assessing infarct size. Therefore, rest99mTc-sestamibi SPET, low-dose dobutamines stress echocardiography and quantitative coronary angiography were performed in 51 patients with a recent myocardial infarction. Perfusion activity and regional wall motion were scored semi-quantitatively using the same segmental division of the left ventricle. Assessment of99mTc-sestamibi uptake as a marker of viability was performed by comparing a binary uptake score (viable=>50% vs necrotic =50% of the maximal tracer activity) with a binary wall motion classification during low-dose dobutamine infusion (viable=normal/hypokinetic vs necrotic=akinetic/dyskinetic). Infarct size, expressed as the number of segments with evidence of necrotic tissue, was significantly greater in the scintigraphic study than in the echocardiographic study (2.8±1.5 vs 2.2±1.3,P=0.006). This overestimation of infarct size by99mTc-sestamibi was present only in patients with a severe infarct-related stenosis (% diameter stenosis 65%–100%) and particularly those with late reperfusion therapy (time delay 180 min). In patients without a severe infarct-related stenosis,99mTc-sestamibi was able to accurately distinguish viable from necrotic segments. Thus, rest99mTc-sestamibi scintigraphy early after acute myocardial infarction may underestimate residual viability within the infarct region, particularly in patients with low flow state coronary anatomy, as a result of a severe infarct-related stenosis and/or late reperfusion therapy.This paper was presented in part at the European Nuclear Medicine Congress, Brussels, Belgium, August 1995 相似文献
5.
目的分析乳腺浸润性导管癌患者的临床病理特征与乳腺专用伽玛显像(BSGI)中99Tcm-甲氧基异丁基异腈(MIBI)摄取之间的关系。 方法回顾性分析2014年3月至2018年3月就诊于威海市立医院行BSGI检查、未接受新辅助治疗及穿刺活组织检查及术前无肿瘤远处转移的浸润性导管癌患者244例的临床资料。分析患者的BSGI数据,计算病灶的放射性计数与正常组织的比值(T/N),从而评估肿瘤对99Tcm-MIBI的摄取量。T/N为偏态分布数据,用M(P25~P75)表示。用Wilcoxon秩和检验分析患者临床病理特征与T/N之间的关系,用多元线性回归模型分析患者临床病理特征对T/N的影响。 结果全部244例患者BSGI中的T/N范围为1.0~7.5。Wilcoxon秩和检验结果显示T/N与T分期、N分期、组织学分级及Ki67表达有关(Z=-6.852、5.198、-3.931,P均<0.001;Z=-3.059, P=0.002),而与ER、PR、HER-2、P53、EGFR表达及三阴性乳腺癌无关(Z= -0.730、-1.526、-1.137、-1.175、-1.224、-1.556, P均>0.050)。多元线性回归分析表明T分期及N分期是T/N的影响因素(t=5.100, 95%CI:0.414~0.935, P<0.001;t= 2.819, 95%CI:0.118~0.668, P=0.005)。 结论乳腺浸润性导管癌的T分期和N分期可能影响BSGI中肿瘤对99Tcm-MIBI的摄取,因此,可以通过术前测定BSGI的T/N,对肿瘤的恶性程度进行初步评估。 相似文献
6.
Zafrir N Arditi A Ben-Gal T Solodky A Hassid Y Sulkes J Battler A 《Clinical cardiology》2003,26(11):530-535
BACKGROUND: The two most useful methods for myocardial viability assessment are perfusion imaging and dobutamine echocardiography. HYPOTHESIS: The present study investigated the additive value of a new method, dobutamine technetium 99m (99mTc)-sestamibi-gated single-photon emission computed tomography (SPECT), which combines these two modalities, to the prediction of wall motion improvement after revascularization. METHODS: Fifty-five consecutive patients with ischemic cardiomyopathy, who were referred for viability evaluation, underwent resting and dobutamine (dose, 5-10 microkg/kg/min) gated SPECT with 99mTc-sestamibi. Of these patients, 36 underwent coronary artery bypass graft (CABG) within 1 month of the study and 32 had repeat resting gated SPECT within 1 year. Global and regional wall motion, wall thickness, and perfusion were simultaneously analyzed at rest and after dobutamine using the 20-segment model; the sestamibi uptake and wall motion response to dobutamine of each segment were rated quantitatively. Based on these findings, the segments were categorized as normal, viable, or nonviable. The predictive values for wall motion improvement were assessed by perfusion, using cutoffs of 50 and 60% of sestamibi uptake, and thereafter by the addition of dobutamine response in the segments that were rated nonviable. RESULTS: Of the 1,080 myocardial segments studied, 906 (84%) had abnormal wall motion and were analyzed for viability. Concordance between perfusion and wall motion response to dobutamine was 60% with the 50% cutoff of sestamibi uptake, and increased to 65% with the 60% sestamibi cutoff (p < 0.04). The respective predictive values of wall motion improvement using the 50 and 60% cutoff points were as follows: sensitivity 93 and 70%, respectively, (p < 0.01); specificity 59 and 86% (p < 0.001), respectively; accuracy 77% for both. The addition of the wall motion response to dobutamine to the assessment of the nonviable segments by perfusion (60% cutoff) increased the sensitivity from 70 to 85% (p = 0.001) and the negative predictive value from 70 to 81% (p = 0.009); the positive predictive value remained high (86 vs. 82%). No additive value of wall motion response to dobutamine was demonstrated for nonviable segments by perfusion with a 50% cutoff. CONCLUSION: Dobutamine sestamibi-gated SPECT is a feasible method for the analysis of myocardial perfusion, function, and contractile reserve of individual myocardial segments in patients with ischemic cardiomyopathy. Viability assessment based on a threshold of 60% uptake of sestamibi, with the addition of the wall motion response to dobutamine in the nonviable segments, seems to yield better predictive values for wall motion improvement after CABG. 相似文献
7.
Coronary subclavian steal is defined as retrograde blood flow from the myocardium through the internal mammary artery graft, secondary to a proximal subclavian artery stenosis. The incidence of this syndrome in patients undergoing internal mammary artery grafts for coronary artery bypass is estimated to be 0.44%. Angiography remains the definitive diagnostic test for confirming this condition. We describe a noninvasive method for evaluating coronary subclavian steal syndrome in a 57-year-old man, with a 50-55% subclavian stenosis confirmed by angiography. Noninvasive evaluation using duplex scanning demonstrated normal vertebral artery blood flow. Technetium 99m-sestamibi (99mTc) imaging confirmed a fixed anterolateral defect. When left-arm isometric exercise was employed, retrograde vertebral artery blood flow was observed by Doppler imaging. A repeat 99mTc-sestamibi study documented an increase in tracer distribution in the anterolateral defect confirming reperfusion of the myocardium through the left internal mammary artery graft. The use of duplex scanning and 99mTc-sestamibi may serve as an adjunct in evaluating coronary subclavian steal syndrome as well as documenting transient vertebral subclavian steal in this patient population. 相似文献
8.
Myocardial perfusion defects and associated systemic ventricular dysfunction in congenitally corrected transposition of the great arteries 总被引:2,自引:1,他引:2
下载免费PDF全文
![点击此处可从《Heart (British Cardiac Society)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
T Hornung E Bernard E Jaeggi R Howman-Giles D Celermajer R Hawker 《Heart (British Cardiac Society)》1998,80(4):322-326
Background—Patients with systemic ventricles of right ventricular morphology are at high risk of contractile dysfunction, the cause of which has not been fully elucidated.
Objective—To assess whether ischaemia or infarction contributes to ventricular impairment in unoperated patients with uncomplicated congenitally corrected transposition of the great arteries (TGA) by studying myocardial perfusion and function.
Setting—Paediatric and adult congenital cardiac clinics of a tertiary referral centre.
Patients—Five patients with congenitally corrected TGA but without associated structural cardiac defects (aged 3.5 to 34 years).
Interventions—Maximal exercise stress testing using standard or modified Bruce protocols. Sestamibi (technetium-99m methoxy isobutyl isonitrile) scanning after isotope injection at maximal exercise and rest.
Main outcome measures—Maximum exercise capacity; right ventricular myocardial perfusion, regional wall motion, and thickening; right ventricular ejection fraction.
Results—The two youngest patients (3.5 and 11 years) had normal exercise capacity for age, while the others had reduced exercise performance. Sestamibi scanning showed reversible myocardial ischaemia in four patients and fixed defects indicating infarction in five. Irreversible defects were mostly associated with impaired wall motion and thickening. The ejection fraction was normal (65%) in the youngest patient but < 55% in the others (mean (SD) 47(11)%).
Conclusions—Patients with unoperated congenitally corrected TGA have a high prevalence of myocardial perfusion defects, with consequent abnormalities of regional wall motion and thickening, and impaired ventricular contractility. These data suggest that ischaemia and infarction are important in the pathogenesis of ventricular failure in this condition.
Keywords: congenitally corrected transposition of the great arteries; ventricular dysfunction; myocardial perfusion; sestamibi scanning 相似文献
Objective—To assess whether ischaemia or infarction contributes to ventricular impairment in unoperated patients with uncomplicated congenitally corrected transposition of the great arteries (TGA) by studying myocardial perfusion and function.
Setting—Paediatric and adult congenital cardiac clinics of a tertiary referral centre.
Patients—Five patients with congenitally corrected TGA but without associated structural cardiac defects (aged 3.5 to 34 years).
Interventions—Maximal exercise stress testing using standard or modified Bruce protocols. Sestamibi (technetium-99m methoxy isobutyl isonitrile) scanning after isotope injection at maximal exercise and rest.
Main outcome measures—Maximum exercise capacity; right ventricular myocardial perfusion, regional wall motion, and thickening; right ventricular ejection fraction.
Results—The two youngest patients (3.5 and 11 years) had normal exercise capacity for age, while the others had reduced exercise performance. Sestamibi scanning showed reversible myocardial ischaemia in four patients and fixed defects indicating infarction in five. Irreversible defects were mostly associated with impaired wall motion and thickening. The ejection fraction was normal (65%) in the youngest patient but < 55% in the others (mean (SD) 47(11)%).
Conclusions—Patients with unoperated congenitally corrected TGA have a high prevalence of myocardial perfusion defects, with consequent abnormalities of regional wall motion and thickening, and impaired ventricular contractility. These data suggest that ischaemia and infarction are important in the pathogenesis of ventricular failure in this condition.
Keywords: congenitally corrected transposition of the great arteries; ventricular dysfunction; myocardial perfusion; sestamibi scanning 相似文献
9.
George M. Segall Carole Stepp Prajoy P. Kadkade Michael W. Dae Elias H. Botvinick 《Journal of nuclear cardiology》1997,4(5):358-363
Background Shortening the acquisition time for myocardial single-photon emission computed tomographic (SPECT) imaging increases patient
comfort and laboratory throughput. The purpose of this study was to compare the diagnostic accuracy for coronary artery disease
detection of myocardial SPECT images acquired in 5 to 10 minutes versus 25 minutes using Tc-99m methoxyisobutylisonitrile
(Tc-99m sestamibi) and a single-head gamma camera.
Methods and Results Forty-one subjects had a standard 1-day rest/stress Tc-99m sestamibi myocardial SPECT study. Two sets of rest and stress images
were acquired on the same day for each subject. One set of images was acquired with a 5- to 10-minute fast acquisition protocol;
the second set of images was acquired with a 25-minute standard protocol. The accuracies of the fast and standard protocols
for identifying individuals with and without coronary artery disease were equivalent. Accuracy was 76% for the fast protocol
and 73% for the standard protocol in individuals with at least one coronary stenosis ≥70%. The accuracies of the two protocols
for identifying individual coronary arteries with stenoses ≥70% also were equivalent. Accuracy was 77% for the fast protocol
and 74% for the standard protocol.
Conclusions SPECT myocardial images may be acquired in as little as 5 to 10 minutes using Tc-99m sestamibi and a 1-day rest/stress protocol.
Accuracy is equivalent to that attained in studies with longer imaging time. 相似文献
10.