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91.
OBJECTIVE: The purpose of this presentation is to show the imaging findings of the common and uncommon variants of adenomyosis as seen on sonography and magnetic resonance imaging (MRI). METHODS: A 3-year database search was performed to identify women who had pelvic sonography and pelvic MRI within a 6-month interval. Images of these cases were retrospectively reviewed. RESULTS: Eighty women were identified. Adenomyosis was diagnosed on MRI, which was used as the reference standard, in 45 of these women. The correct diagnosis was made on sonography in 73% of the cases. CONCLUSIONS: Awareness of the spectrum of imaging features of adenomyosis is important to use sonography effectively for diagnosing this entity and to help avoid misdiagnosis.  相似文献   
92.
93.
BACKGROUND: Dynamic single photon emission computed tomography (SPECT) acquisition and reconstruction of early poststress technetium 99m teboroxime washout images has been shown to be useful in the detection of coronary disease. Assessment of poststress regional wall motion may offer additional use in assessing coronary disease. Our goal was to investigate the feasibility of simultaneously imaging myocardial ischemia and transient poststress akinesis using gated-dynamic SPECT. METHODS AND RESULTS: A gated-dynamic mathematical cardiac torso (MCAT) phantom was developed to model both teboroxime kinetics and cardiac regional wall motion. A lesion was simulated as having delayed poststress teboroxime washout together with a transient poststress wall motion abnormality. Gated projection data were created to represent a 3-headed SPECT system undergoing a total rotation of 480 degrees . The dynamic expectation-maximization reconstruction algorithm with postsmoothing across gating intervals by Wiener filtering, and the ordered-subset expectation maximization reconstruction algorithm with 3-point smoothing across gating intervals were compared. Compared with the ordered-subset expectation maximization with 3-point smoothing, the dynamic expectation-maximization algorithm with Wiener filtering was able to produce visually higher-quality images and more accurate left ventricular ejection fraction estimates. CONCLUSION: From simulations, we conclude that changing cardiac function and tracer localization possibly can be assessed by using a gated-dynamic acquisition protocol combined with a 5-dimensional reconstruction strategy.  相似文献   
94.
In vivo diagnosis with cancer-specific targeting agents that have optimal characteristics for imaging is an important development in treatment planning for cancer patients. Overexpression of the HER2 antigen is high in several types of carcinomas and has predictive and prognostic value, especially for breast cancer. A new type of targeting agent, the Affibody molecule, was described recently. An Affibody dimer, His6-(ZHER2:4)2 (15.4 kDa), binds to HER2 with an affinity of 3 nmol/L and might be used for the imaging of HER2 expression. The use of 99mTc might improve the availability of the labeled conjugate, and Tc(I)-carbonyl chemistry enables the site-specific labeling of the histidine tag on the Affibody molecule. The goals of the present study were to prepare 99mTc-labeled His6-(ZHER2:4)2 and to evaluate its targeting properties compared with the targeting properties of 125I-4-iodobenzoate-His6-(ZHER2:4)2 [125I-His6-(ZHER2:4)2]. METHODS: The labeling of His6-(ZHER2:4)2 with 99mTc was performed with an IsoLink kit. The specificity of 99mTc-His6-(ZHER2:4)2 binding to HER2 was evaluated in vitro with SK-OV-3 ovarian carcinoma cells. The comparative biodistributions of 99mTc-His6-(ZHER2:4)2 and 125I-His6-(ZHER2:4)2 in tumor-bearing BALB/c nu/nu mice were determined. RESULTS: The labeling yield for 99mTc-His6-(ZHER2:4)2 was approximately 60% (50 degrees C), and the radiochemical purity was greater than 97%. The conjugate was stable during storage and under histidine and cysteine challenges and demonstrated receptor-specific binding. The biodistribution study demonstrated tumor-specific uptake levels (percentage injected activity per gram of tissue [%IA/g]) of 2.6 %IA/g for 99mTc-His6-(ZHER2:4)2 and 2.3 %IA/g for 125I-His6-(ZHER2:4)2 at 4 h after injection. Both conjugates provided clear imaging of SK-OV-3 xenografts at 6 h after injection. The tumor-to-nontumor ratios were much more favorable for the radioiodinated Affibody. CONCLUSION: The use of Tc(I)-carbonyl chemistry enabled us to prepare a stable, site-specifically labeled 99mTc-His6-(ZHER2:4)2 conjugate that was able to bind to HER2-expressing cells in vitro and in vivo. The indirectly radioiodinated conjugate provided better tumor-to-liver ratios. The labeling of Affibody molecules with 99mTc should be investigated further.  相似文献   
95.
Prolonged antipseudomonal parenteral antibiotic therapy combined with daily aural toilet has been effective in resolving long standing ear discharge in children with chronic suppurative otitis media. However, such treatment suffered from the disadvantages of prolonged hospitalization. We conducted a prospective study to investigate the feasibility and efficacy of exclusive outpatient treatment of children with chronic suppurative otitis media without cholesteatoma who had failed ototopical/oral antimicrobial therapy. The treatment consisted of daily aural toilet (suction and debridement) and twice daily parenteral ceftazidime (50 mg/kg/dose). Thirty-seven children were included. The duration of discharge from the ear before treatment was 6 to 121 months (median, 30 months). Aerobic cultures yielded Pseudomonas aeruginosa in 97%, often with other organisms. The management and follow-up were performed jointly by otolaryngology and infectious diseases physicians using the hospital ambulatory services. The route of ceftazidime administration (intravenous or intramuscular) was chosen according to the parents' and patients' convenience. Discharge stopped within 3 to 20 days (median, 8 days) in all children but one. Seventy-six percent of the 29 children available for follow-up 12 months after treatment were still free of discharge. Our results demonstrate that a regiment combining daily aural toilet and twice daily parenteral ceftazidime is highly efficacious in resolving ear discharge in children with chronic suppurative otitis media without cholesteatoma and that such a regimen does not require hospitalization.  相似文献   
96.
Benign neonatal sleep myoclonus (BNSM), characterized by myoclonic jerks of the extremities only in non-REM sleep, occurs in the first months of life with spontaneous disappearance within 3-4 months. We examined five siblings with typical BNSM, at the 3-10 years follow-up neurological examination. Psychomotor development, cognitive functions and EEG were completely normal. These cases confirm that BNSM is a self limited and nonepileptic disorder.  相似文献   
97.
Epidermal growth factor receptor plays an important role in the pathogenesis of many malignancies. Various growth factors, including epidermal growth factor receptor, have been shown to influence pituitary tumor growth and differentiation. To analyze the role of epidermal growth factor receptor in pituitary tumor development, we examined normal pituitaries (n=8), pituitary adenomas (n=158), and pituitary carcinomas (n=7) for expression of epidermal growth factor receptor protein and messenger RNA using tissue microarrays and RT-PCR. We also examined (a) the expression of phospho-epidermal growth factor receptor, the activated form of epidermal growth factor receptor, in pituitary tumors and normal pituitaries by immunohistochemistry and (b) the effects on epidermal growth factor receptor expression of treating pituitary cells (HP75 cell line) with epidermal growth factor. Epidermal growth factor receptor and the phosphorylated variant expression were present in normal pituitary cells. Epidermal growth factor receptor messenger RNA was also detected in normal pituitaries, pituitary adenomas, and carcinomas by in situ hybridization and RT-PCR. Most pituitary adenomas showed expression of epidermal growth factor receptor and the phosphorylated variant. Nonfunctional adenomas showed higher levels of expression of epidermal growth factor receptor (76 vs 34%) and of phospho-epidermal growth factor receptor (26 vs 8%) as compared to functional adenomas. Five of seven pituitary carcinomas showed strong expression of both epidermal growth factor receptor and phospho-epidermal growth factor receptor. When a human pituitary cell line (HP75) was cultured in the presence of epidermal growth factor receptor, there was an increase in the levels of both epidermal growth factor receptor and phospho-epidermal growth factor receptor after 5 h of treatment, thus confirming that epidermal growth factor receptor signaling was active in pituitary tumors. These results indicate that activated epidermal growth factor receptor is expressed in pituitary adenomas and carcinomas. Higher levels in pituitary carcinomas suggest a role in pituitary tumor progression.  相似文献   
98.
Failure to retain health professionals in rural areas contributes to the poor health status of these communities through an inability to deliver reliable and consistent services. Considerable attention has been focused on factors affecting recruitment of health professionals. Far less is known about factors affecting the retention of occupational therapists. This was the focus of this study. Ethnographic interviews were used to explore the experiences of 10 occupational therapists who had left rural practice. Six themes emerged from the participants' experiences, from when they first considered rural practice to reflections following their departure from it. These themes were initial appeal, facing the challenge, rural practice issues, the social sphere, reasons for leaving and the value of rural experience. These factors gave rise to a proposed Model of Retention Equilibrium, which suggests that retention can be improved by addressing the imbalance between incentives to leave and incentives to stay. The model provides a useful framework for occupational therapists contemplating rural practice, as well as for health services managers responsible for service delivery in rural areas.  相似文献   
99.
Homogeneous and stable layers were deposited through allylamine plasma polymerization (75 W, 100 Pa, 15 min) onto poly[(3-hydroxybutyric acid)-co-(3-hydroxyvaleric acid)] (91 : 9 wt.-%) (P(HB-co-9%HV)) film surfaces, XPS analysis using take-off angles of 20° and 70° and performed 10 days and 20 days after plasma treatment gives information on the composition (in atom%) of the modified surface: C, 62.74; N, 19.60; O, 17.65. The unexpected oxygen percentage is weaker if argon plasma pretreatment (25 W, 40 Pa, 5 min) is applied. Then, a succinct mechanism is proposed. The study of changes in element ratios and binding energy values shows that the majority of incorporated functional groups seem to be amide and imine groups.  相似文献   
100.
Abstract Facial gingival surfaces of maxillary and mandibular anterior teeth were monitored to evaluate changes of the width of the keratinized and attached gingiva. 96 children 6 to 12 years of age were examined 2 × with an interval of 2 years. Measurements included dental plaque, gingival inflammation, probing depth, and width of keratinized and attached gingiva. In addition, study models were used to determine the facial/lingual position of the teeth. The results of this report, evaluating well-aligned teeth only, showed that during the 2-year observation period, increases in widths of the facial keratinized and attached gingiva took place. Increases occurred for the various teeth regions examined, and for deciduous as well as permanent teeth. During transition from the deciduous to the permanent dentition, patterns of change were variable. The increase of gingival widths was greatest for sites with the smallest baseline width of attached gingiva, and smallest for sites with the greatest baseline width. It was concluded that in well-aligned teeth, a conservative, monitoring approach prior to a corrective, surgical intervention seems prudent in children of this age with a minimal zone or absence of attached gingiva.  相似文献   
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