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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
The purpose of the study was to compare the performance of full-field digital mammography (FFDM) with soft-copy reading to
screen film mammography (SFM) used during the first prevalent 2-year round of population-based screening. A total of 18,239
women aged 50–69 years were screened with FFDM as part of the Norwegian Breast Cancer Screening Programme (NBCSP). Process
indicators were compared to data from 324,763 women screened with SFM using the common national database of the NBCSP. The
cancer detection rates were 0.77% (140/18,239) for FFDM and 0.65% (2,105/324,763) for SFM (p = 0.058). For ductal carcinoma
in situ (DCIS) alone, the results were: FFDM 0.21% (38/18,239) compared to SFM 0.11% (343/324,763) (p < 0.001). Recall rates
due to positive mammography were for FFDM 4.09% (746/18,239), while for SFM 4.16% (13,520/324,764) (p = 0.645), due to technically
insufficient imaging: FFDM 0.22% (40/18,239) versus SFM 0.61% (1,993/324,763) (p < 0.001). The positive predictive value (PPV)
in the FFDM group was 16.6% (140/843), while 13.5% (2,105/15,537) for SFM (p = 0.014). No statistically significant differences
were recorded concerning histological morphology, tumour size, or lymph node involvement. In conclusion FFDM had a significantly
higher detection rate for DCIS than SFM. For invasive cancers no difference was seen. FFDM also had a significantly higher
PPV and a significantly lower technical recall rate. 相似文献
992.
Okuma T Matsuoka T Yamamoto A Oyama Y Toyoshima M Nakamura K Inoue Y 《Cardiovascular and interventional radiology》2008,31(1):122-130
Objective To retrospectively determine the frequency and risk factors of various side effects and complications after percutaneous computed
tomography–guided radiofrequency (RF) ablation of lung tumors.
Methods We reviewed and analyzed records of 112 treatment sessions in 57 of our patients (45 men and 12 women) with unresectable lung
tumors treated by ablation. Risk factors, including sex, age, tumor diameter, tumor location, history of surgery, presence
of pulmonary emphysema, electrode gauge, array diameter, patient position, maximum power output, ablation time, and minimum
impedance during ablation, were analyzed using univariate and multivariate analyses.
Results Total rates of side effects and minor and major complications occurred in 17%, 50%, and 8% of treatment sessions, respectively.
Side effects, including pain during ablation (46% of sessions) and pleural effusion (13% of sessions), occurred with RF ablation.
Minor complications, including pneumothorax not requiring chest tube drainage (30% of sessions), subcutaneous emphysema (16%
of sessions), and hemoptysis (9% of sessions) also occurred after the procedure. Regarding major complications, three patients
developed fever >38.5°C; three patients developed abscesses; two patients developed pneumothorax requiring chest tube insertion;
and one patient had air embolism and was discharged without neurologic deficit. Univariate and multivariate analyses suggested
that a lesion located ≤1 cm of the chest wall was significantly related to pain (p < 0.01, hazard index 5.76). Risk factors for pneumothorax increased significantly with previous pulmonary surgery (p < 0.05, hazard index 6.1) and presence of emphysema (p <0.01, hazard index 13.6).
Conclusion The total complication rate for all treatment sessions was 58%, and 25% of patients did not have any complications after RF
ablation. Although major complications can occur, RF ablation of lung tumors can be considered a safe and minimally invasive
procedure. 相似文献
993.
Tamashiro A Miceli MH Rando C Tamashiro GA Villegas MO Dini AE Balestrin AE Diaz JA 《Cardiovascular and interventional radiology》2008,31(3):633-637
The objective of this paper is to present an alternative therapeutic approach for the treatment of patients with massive hemoptysis
in whom bronchial and/or nonbronchial systemic arterial embolization is not possible. We describe a percutaneous procedure
for pulmonary segmental artery embolization. Between May 2000 and July 2006, 27 adult patients with hemoptysis underwent percutaneous
treatment at our department; 20 of 27 patients were embolized via bronchial and or nonbronchial systemic arteries and 7 patients
were embolized via pulmonary artery. Femoral arterial access for systemic artery catheterization and femoral vein access for
pulmonary arterial catheterization were used. Gelfoam particles and coils were used for embolization. In this study, we report
on three cases of massive hemoptysis from a systemic arterial source in whom bronchial and/or nonbronchial arteries embolization
was not possible. Percutaneous embolization via the pulmonary artery access was successful in all three patients. In conclusion,
embolization via pulmonary artery is presented as an alternative approach for the management of hemoptysis in patients in
whom bronchial arterial embolization is not possible. 相似文献
994.
Fanelli F Orgera G Bezzi M Rossi P Allegritti M Passariello R 《European radiology》2008,18(5):911-919
To evaluate the efficacy and safety of an expanded polytetrafluoroethylene-fluorinated ethylene-propylene (ePTFE/FEP)-covered
metallic stent in the management of malignant biliary obstruction. Eighty consecutive patients with malignant common bile
duct strictures were treated by placement of 83 covered metallic stents. The stent-graft consists of an inner ePTFE/FEP lining
and an outer supporting structure of nitinol wire. Clinical evaluation, assessment of serum bilirubin and liver enzyme levels
were analyzed before biliary drainage, before stent-graft placement and during the follow-up period at 1, 3, 6, 9 and 12 months.
Technical success was obtained in all cases. After a mean follow-up of 6.9±4.63 months, the 30-day mortality rate was 14.2%.
Survival rates were 40% and 20.2% at 6 and 12 months, respectively. Stent-graft patency rates were 95.5%, 92.6% and 85.7%
at 3, 6 and 12 months, respectively. Complications occurred in five patients (6.4%); among these, acute cholecystitis was
observed in three patients (3.8%). A stent-graft occlusion rate of 9% was observed. The percentage of patients undergoing
lifetime palliation (91%) and the midterm patency rate suggest that placement of this ePTFE/FEP-covered stent-graft is safe
and highly effective in achieving biliary drainage in patients with malignant strictures of the common bile duct. 相似文献
995.
Rezende MT Spelle L Piotin M Mounayer C Lucas Cde P Abud DG Moret J 《Neuroradiology》2008,50(5):443-446
A 4-year-old girl suffered intraventricular and subarachnoid hemorrhage during endoscopic third ventriculostomy. Cerebral
angiography revealed a traumatic basilar aneurysm secondary to basilar artery injury. The aneurysm was treated with selective
endovascular embolization using Guglielmi detachable coils. We review some therapeutic features of traumatic basilar aneurysms
after endoscopic third ventriculostomy and describe the feasibility of endovascular selective therapy to manage these lesions
successfully. 相似文献
996.
Olaf Lorbach Andreas Diamantopoulos Klaus-Peter Kammerer Hans H. Paessler 《Knee surgery, sports traumatology, arthroscopy》2008,16(4):348-352
Resection of the lower patellar pole provides good results in the treatment of jumper’s knee. Therefore we hypothesized that
the length of the lower patellar pole is increased in patients with chronic patellar tendinopathy. Cohort study, level of
evidence 2. Between 2000 and 2005, 25 patients with chronic patellar tendinopathy underwent conservative and surgical treatment
in our clinic. All of them had preoperative MRI were three independent examiners measured the Caton Index, the length and
the ratio of the articular and non-articular patellar surface, tendon length and thickness and the thickness and length of
the hypodens lesions in the patellar tendon. The measurements were compared with 50 MRI of a control group with no clinical
patellofemoral disorders or patellar tendinopathy. Significant changes in tendon thickness (9.42 ± 2.87 vs. 4.88 ± 1.13; P < 0.0001), a longer non-articular surface of the patella (10.62 ± 2.86 vs. 7.098 ± 2.53; P < 0.0001) and significant higher ratio between the articular and the non-articular patellar surface (0.32 vs. 0.24; P < 0.0001) were found in the jumper’s knee group. No significant changes were seen in the length of the articular surface
or the Caton Index. The development of chronic patellar tendinopathy in athletes might be associated with a longer lower patellar
pole as patients with jumper’s knee showed a longer non-articular patellar surface compared with the control group. 相似文献
997.
Chondroid lipoma is a rare variant of lipoma that pathologically can mimic liposarcoma or possibly other sarcomas. Variants
of lipoma, including chondroid lipoma, may demonstrate radiological evidence of fat within the tumor, but often display heterogeneous
features on imaging studies, making a clinical diagnosis difficult. A large collective experience with the imaging characteristics
of chondroid lipoma is lacking due to the rarity of this tumor. We present a case of chondroid lipoma of the upper thigh in
a 37-year-old woman who had regions of metaplastic bone formation within the tumor. Radiologically, the tumor presented as
a large soft tissue mass with calcification and ossification. Although metaplastic bone formation in conventional lipoma is
well described, it has been rarely reported to occur in chondroid lipoma and has not been pathologically documented or illustrated.
The imaging findings and histopathology of this unusual tumor are presented, along with a review of the literature. 相似文献
998.
Apurva A. Motivala Patricia A. Rose H. Myra Kim Yolanda R. Smith Catherine Bartnik Robert D. Brook Otto Muzik Claire S. Duvernoy 《Journal of nuclear cardiology》2008,15(4):510-517
Background. This study was designed to determine whether overweight or obese status is independently associated with myocardial flow
reserve (MFR), an established predictor of cardiovascular mortality, in a group of postmenopausal women with no previous cardiovascular
disease. Postmenopausal women are the largest group of overweight and physically inactive individuals in the United States.
Increased body mass index (BMI) is consistently associated with increased cardiovascular mortality in this population. Whether
this is because of obesity itself or the accompanying increase in cardiovascular risk factors (CRFs) remains controversial.
Methods. We examined the relationship of myocardial blood flow (MBF), coronary vascular resistance, and MFR to BMI in 60 postmenopausal
women with no coronary heart disease. Subjects underwent dynamic N-13 ammonia positron emission tomography for the measurement
of MBF and MFR. Baseline demographics, CRF, and hemodynamic parameters were recorded for each subject. Datasets were divided
into 3 groups according to BMI: normal (18 to 24), overweight (25 to 29), and obese (≥30).
Results. The overweight and obese groups showed significantly higher resting MBF and lower MFR than the normal-weight group (both
P<.001), even after adjusting for CRF. A further analysis of subjects without any CRF (n=35) showed that the MFR remained significantly
lower in the obese compared with normal-weight subjects (P=.05). Levels of known markers of vascular inflammation (high-sensitivity C-reactive protein and homocysteine) and high-density
lipoprotein cholesterol levels correlated with declining MFR.
Conclusions. These findings provide a mechanistic link between obesity and coronary heart disease in this population.
This study was funded by a Veterans Health Administration MERIT Review Award.
C.S.D. is on the Speaker’s Bureau at Pfizer, Inc., and has received grant support from Pfizer, Inc., Eli Lilly & Co., and
the Veterans Health Administration. 相似文献
999.
Edward D. Nicol James Stirrup Eliana Reyes Michael Roughton Simon P. G. Padley Michael B. Rubens S. Richard Underwood 《Journal of nuclear cardiology》2008,15(4):497-502
Background. Cardiac computed tomography (CCT) has the potential to assess both coronary anatomy and ventricular function in a single
study. We examined the agreement between CCT and myocardial perfusion scintigraphy (MPS) for the assessment of global and
regional ventricular function.
Methods and Results. Research CCT was performed in 52 patients with a low to intermediate likelihood of coronary artery disease referred for
MPS. Left ventricular enddiastolic volume, left ventricular end-systolic volume, left ventricular ejection fraction (LVEF),
and myocardial wall motion and thickening were compared between techniques. In addition, myocardial contrast attenuation on
CCT was compared with radiotracer uptake on MPS. LVEF values agreed well (mean difference, 4.1%; SD, 15.13%), but CCT left
ventricular end-diastolic volume was greater compared with MPS (mean difference, 46.0 mL; SD, 33.34 mL) (P<.001). There was moderate agreement for segmental myocardial motion and thickening, with κ values of 0.57 (95% confidence
interval, 0.51–0.63) and 0.47 (95% confidence interval, 0.41–0.53), respectively. Seventeen patients had hypoattenuation in
at least 1 myocardial segment on CCT. Three of four patients with concomitant abnormalities of wall motion and thickening
on CCT had infarction in the same territory on MPS.
Conclusions. There was good agreement for LVEF between CCT and MPS but myocardial volumes differed, and these modalities cannot be used
interchangeably. Mild abnormalities of regional function are detected more commonly by CCT than by MPS. Myocardial hypoattenuation
on CCT is highly specific for myocardial infarction when associated with reduction of systolic wall thickening and regional
wall motion abnormality.
Dr Nicol received a grant from the Defence Postgraduate Medical Deanery. 相似文献
1000.
Clinical and structural results of partial supraspinatus tears treated by subacromial decompression without repair 总被引:1,自引:0,他引:1
Dennis Liem Semra Alci Nicolas Dedy Jörn Steinbeck Björn Marquardt Gunnar Möllenhoff 《Knee surgery, sports traumatology, arthroscopy》2008,16(10):967-972
Patients with primary impingement and articular sided partial tears of the supraspinatus are often treated by subacromial
decompression without repair, if the extent of the tear is estimated to be below 50% of tendon thickness. It has been questioned
whether repair of these cuff lesions is necessary, because these tears could progress to full thickness tears with deteriorating
clinical results. Our hypothesis was that subacromial decompression without repair of the supraspinatus tendon leads to significant
clinical improvement for patients with grade I and II articular sided tears without progression to a full thickness tear on
a regular basis. 46 consecutive patients (av. Age 59.2 years, range 33–76.6 years) were retrospectively reviewed after an
average follow up of 50.3 months (36–86 months). 26 patients (43.5%) had a grade I tear according to Ellman, which was left
alone, 20 patients suffered from a grade II tear, which was debrided. Clinical outcome was assessed with the ASES Score and
ultrasound evaluation was performed on all patients to detect possible progression to a full thickness tear. The average ASES
Score significantly improved from 37.4 to 86.6 points (p < 0.0001). The mean postoperative Constant Score was 87.6 points. Only three patients (6.5%) progressed to a full thickness
tear detectable on ultrasound examination. Only one of these patients had a poor result with an ASES Score of 35 points, the
other two were very satisfied and had an ASES score above 90 points. 8 patients showed no more signs of partial tearing on
ultrasound and these patients had an average ASES Score of 93.1 points. Overall clinical outcome was rated excellent in 35
cases (76.1%), good in 5 (10.9%), average in 2 (4.3%) and poor in 4 (8.7%). Our results indicate that good and excellent results
can be achieved mid- to long term by acromioplasty without repair of the rotator cuff in articular sided partial tears grade
I and II. These results reach almost 95% of the value of a healthy shoulder. A better result on ultrasound examination was
associated with a superior clinical outcome, while progression to a full thickness tear was rare. 相似文献