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991.
Folpe AL 《Skeletal radiology》2007,36(9):899-900
992.
MR imaging of the alar ligament: morphologic changes during axial rotation of the head in asymptomatic young adults 总被引:2,自引:0,他引:2
OBJECTIVE:. The alar ligament plays a critical role in limiting the axial rotation of the head, the left alar ligament being stretched on rotation to the right and vice versa. The purposes of this study were to assess the usefulness of MR imaging in demonstrating the alar ligament and also to identify its morphologic changes during axial rotation of the head in asymptomatic young volunteers. DESIGN AND PATIENTS:. Twenty-two healthy volunteers participated in this study. All subjects underwent four series of contiguous fast spin echo density-weighted MR images with a 2 mm slice thickness including axial and coronal images with the head in neutral position, and coronal images with alternate head rotation to the right and left. The alar ligaments seen on each series of MR images were visually graded 0-2, and grade comparisons were performed between the four series of MR images. We also assessed the morphologic changes of the alar ligament on coronal images during axial rotation of the head. RESULTS:. Grade comparisons for the demonstration of the alar ligament revealed that each of three series of coronal images was statistically significantly better in grade than axial images. During axial rotation of the head, MR images showed rather constant morphologic changes of the alar ligament: elevation and wrapping of the contralateral alar ligament around the dens, associated with slightly upward movement of C1-C2 on that side. This wrap-around effect of the contralateral alar ligament in relation to the dens sometimes caused the apparent shortening of the alar ligament on that side. CONCLUSION:. Reliable assessment of the anatomy and function of the alar ligament can be achieved with MR imaging, preferably in coronal planes. MR imaging with the aid of a functional study may be a valuable imaging modality in the evaluation of alar ligament failure. 相似文献
993.
994.
"Seeing inside the body": MR imaging of gene expression 总被引:5,自引:0,他引:5
Högemann D Basilion JP 《European journal of nuclear medicine and molecular imaging》2002,29(3):400-408
The goal of this review is to describe the developments and recent advances that are enabling applications of magnetic resonance (MR) imaging for non-invasive imaging of gene expression. Guiding application of this technology has been the need to test, in vivo and in real time, hypotheses developed in multiple scientific fields. Advances made in the human genome project and our increasing understanding of the molecular basis of normal and disease physiology have defined questions that will only be answered when specific molecular imaging modalities are developed. In this review we will briefly summarize the salient features of MR imaging to provide the backdrop for a more detailed discussion of specific applications of MR imaging of gene expression. We will conclude with the insights gained from genomic approaches and how they might be exploited for MR imaging of gene expression in the future. 相似文献
995.
New frontiers in CT imaging of airway disease 总被引:7,自引:0,他引:7
Grenier PA Beigelman-Aubry C Fétita C Prêteux F Brauner MW Lenoir S 《European radiology》2002,12(5):1022-1044
Combining helical volumetric CT acquisition and thin-slice thickness during breath hold provides an accurate assessment of both focal and diffuse airway diseases. With multiple detector rows, compared with single-slice helical CT, multislice CT can cover a greater volume, during a simple breath hold, and with better longitudinal and in-plane spatial resolution and improved temporal resolution. The result in data set allows the generation of superior multiplanar and 3D images of the airways, including those obtained from techniques developed specifically for airway imaging, such as virtual bronchography and virtual bronchoscopy. Complementary CT evaluation at suspended or continuous full expiration is mandatory to detect air trapping that is a key finding for depicting an obstruction on the small airways. Indications for CT evaluation of the airways include: (a) detection of endobronchial lesions in patients with an unexplained hemoptysis; (b) evaluation of extent of tracheobronchial stenosis for planning treatment and follow-up; (c) detection of congenital airway anomalies revealed by hemoptysis or recurrent infection; (d) detection of postinfectious or postoperative airway fistula or dehiscence; and (e) diagnosis and assessment of extent of bronchiectasis and small airway disease. Improvement in image analysis technique and the use of spirometrically control of lung volume acquisition have made possible accurate and reproducible quantitative assessment of airway wall and lumen areas and lung density. This contributes to better insights in physiopathology of obstructive lung disease, particularly in chronic obstructive pulmonary disease and asthma. 相似文献
996.
MR imaging features of solid pseudopapillary tumor of the pancreas in adult and pediatric patients 总被引:24,自引:0,他引:24
Cantisani V Mortele KJ Levy A Glickman JN Ricci P Passariello R Ros PR Silverman SG 《AJR. American journal of roentgenology》2003,181(2):395-401
OBJECTIVE: This study was conducted to describe the MR imaging features of solid pseudopapillary tumor of the pancreas. CONCLUSION: Solid pseudopapillary tumor of the pancreas, a tumor typically seen in young women, is a large, well-defined, encapsulated lesion with heterogeneous high or low signal intensity on T1-weighted, heterogeneous high signal intensity on T2-weighted, and early peripheral heterogeneous enhancement with progressive fill-in on gadolinium-enhanced dynamic MR imaging. These features help differentiate this rare tumor from other pancreatic neoplasms. 相似文献
997.
Gerardo Zambrano Alina Sekretareva Daniele D'Alonzo Linda Leone Vincenzo Pavone Angela Lombardi Flavia Nastri 《RSC advances》2022,12(21):12947
The miniaturized metalloenzyme Fe(iii)-mimochrome VI*a (Fe(iii)-MC6*a) acts as an excellent biocatalyst in the H2O2-mediated oxidative dehalogenation of the well-known pesticide and biocide 2,4,6-trichlorophenol (TCP). The artificial enzyme can oxidize TCP with a catalytic efficiency (kcat/KTCPm = 150 000 mM−1 s−1) up to 1500-fold higher than the most active natural metalloenzyme horseradish peroxidase (HRP). UV-visible and EPR spectroscopies were used to provide indications of the catalytic mechanism. One equivalent of H2O2 fully converts Fe(iii)-MC6*a into the oxoferryl-porphyrin radical cation intermediate [(Fe(iv) O)por˙+], similarly to peroxidase compound I (Cpd I). Addition of TCP to Cpd I rapidly leads to the formation of the corresponding quinone, while Cpd I decays back to the ferric resting state in the absence of substrate. EPR data suggest a catalytic mechanism involving two consecutive one-electron reactions. All results highlight the value of the miniaturization strategy for the development of chemically stable, highly efficient artificial metalloenzymes as powerful catalysts for the oxidative degradation of toxic pollutants.The artificial metalloenzyme FeMC6*a is able to perform the H2O2-mediated dechlorination of 2,4,6-trichlorophenol with unrivalled catalytic efficiency, highlighting its potential application for the removal of toxic pollutants. 相似文献
998.
Seth J. Barishansky Anne P. Hutchinson Angela K. Lawson Mary Ellen Pavone 《Journal of assisted reproduction and genetics》2022,39(6):1399
ObjectiveTo evaluate predictors for patient preference regarding multifetal or singleton gestation among women presenting for infertility care.DesignCross-sectional study.SettingAcademic university hospital-based infertility clinic.Patient(s)Five hundred thirty-nine female patients with infertility who presented for their initial visit.Main outcome measure(s)Demographic characteristics, infertility history, insurance coverage, desired treatment outcome, acceptability of multifetal reduction, and knowledge of the risks of multifetal pregnancies were assessed using a previously published 41-question survey. Univariate analysis was performed to assess patient factors associated with the desire for multiple births. Independent factors associated with this desire were subsequently assessed by multivariate logistic regression analysis.Result(s)Nearly a third of women preferred multiples over a singleton gestation. Nulliparity, lower annual household income, older maternal age, marital status, larger ideal family size, openness to multifetal reduction, and lack of knowledge of the maternal/fetal risks of twin pregnancies were associated with pregnancy desire. Older age (OR (95% CI) 1.66 (1.20–2.29)), nulliparity (OR (95% CI) 0.34 (0.20–0.58)), larger ideal family size (OR (95% CI) 2.34 (1.73–3.14)), and lesser knowledge of multifetal pregnancy risk (OR (95% CI) 0.67 (0.55–0.83)) were independently associated with desire.Conclusion(s)A large number of patients undergoing fertility treatment desire multifetal gestation. Although a lack of understanding of the risks associated with higher order pregnancies contributes to this desire, additional individual specific variables also contribute to this trend. Efforts to reduce the incidence of multiples should focus not only on patient education on comparative risks of multiples vs singleton pregnancies but also account for individual specific reservations. 相似文献
999.
Introduction Idiopathic granulomatous mastitis (IGM) is a rare benign inflammatory breast disease that presents with variable local manifestations.
We describe here the different management protocols based on the clinical presentation of these patients.
Methods A retrospective review of 20 histopathologic confirmed cases of IGM seen over a period of 10 years was performed.
Results The median age was 34 years (age range: 21–45 years). All were married, parous with history of breast feeding. Ill-defined
mass mimicking carcinoma was the commonest presentation (70%); however, with the presence of signs of inflammation like pain
(55%), redness (40%), and peau d’orange (40%), an inflammatory process appeared more likely. Axillary lymph node enlargement
was infrequently seen (40%). Radiologic findings (mammography and ultrasound) were nonspecific. Histopathology showed the
characteristic lobular distribution of granulomatous inflammation in all cases. Surgically, 7 patients had abscess drainage
with open biopsy, and 7 patients had lumpectomy. Six patients with diffuse breast involvement were diagnosed by core needle
biopsy only. Microbial cultures showed no growth. Antibiotics were given empirically when signs of inflammation where present.
Two patients needed further abscess drainage followed by persistent sinus excision 3–6 weeks later. The median follow-up was
24 months (range: 15–42 months). Seventeen patients (85%) were recurrence-free, and 3 patients (15%) were lost to follow-up.
Conclusions Management of IGM cases needs to be tailored according to the clinical presentation. Precise radiologic and pathologic data
interpretation by a multidisciplinary breast team will facilitate diagnosis and minimize unnecessary intervention. 相似文献
1000.
Emanuele Soricelli Giovanni Casella Mario Rizzello Benedetto Calì Giorgio Alessandri Nicola Basso 《Obesity surgery》2010,20(8):1149-1153