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41.
The aim of this study was to investigate the usefulness of contrast-enhanced harmonic power Doppler ultrasound (US) for the
detection of residual viable hepatocellular carcinoma (HCC) after treatment with transcatheter arterial chemoembolization
(TACE). Forty-seven patients with 68 HCC lesions 1.8–9.5 cm in diameter (mean ± SD 4.3 ± 1.7 cm) underwent contrast-enhanced
power Doppler US, in the harmonic mode, before and after treatment with TACE. Unenhanced spiral CT and contrast-enhanced dynamic
MR imaging were also performed to help establish the outcome of therapy. Before treatment, intratumoral blood flow signals
were detected at contrast-enhanced harmonic power Doppler US in 65 (95 %) of 68 lesions. After TACE, flow signals were no
longer detectable in 22 of these 65 lesions, which showed complete response at spiral CT and dynamic MR imaging. In 38 (88
%) of the 43 lesions with partial response, intratumoral flow signals were still identified at contrast-enhanced harmonic
power Doppler US. Twenty-eight of these 38 lesions underwent additional treatment with percutaneous ethanol injection (PEI)
using contrast-enhanced harmonic power Doppler US guidance. Complete response was seen after PEI in 23 of 28 lesions. Contrast-enhanced
harmonic power Doppler US proved useful for assessing the therapeutic effect of TACE on HCC and for guiding additional treatment
with PEI in cases of partial response.
Received: 25 January 2000; Revised: 21 April 2000; Accepted: 25 April 2000 相似文献
42.
Neri E Caramella D Cosottini M Zampa V Jackson A Berrettini S Sellari-Franceschini S Bartolozzi C 《European radiology》2000,10(1):114-118
Our aim was to verify the feasibility of volume rendering (VR) of high-resolution magnetic resonance (HR-MR) data sets of
the labyrinth. We retrospectively reviewed the HR-MR data sets of 16 consecutive patients with no MR evidence of labyrinthine
pathology. High-resolution MR data sets were obtained by means of a 3D T2-weighted FSE sequence with the use of a 3-in. circular
surface coil for signal reception, and processed with a high-end workstation. Two reviewers performed separately VR of the
labyrinth by selecting the signal intensity interval for attribution of opacity and transparency. Concerning the time taken
for definition of the volume of interest, the two observers needed, respectively, 28.9 and 33.1 min (SD ± 8.7–9.5 min), whereas
the time taken for VR was respectively, 26 and 33.2 min (SD ± 8.8–8.9 min). Concerning the selection of the signal intensity
interval, the two observers had, respectively, 86.4 and 88.7 mean lower threshold (SD ± 34.5–33.5), 488.9 and 495.4 mean upper
threshold (SD ± 56.3–53.8). In our experience, we have found VR of HR-MR to offer a reliable and reproducible technique for
producing 3D representations of the labyrinth. The VR algorithms use all data within the imaging volume and optimize the dynamic
range ascribed to the object being visualized.
Received: 9 October 1998; Revised: 14 January 1999; Accepted: 30 June 1999 相似文献
43.
Effects of hyaluronan on free-radical formation, corneal endothelium damage, and inflammation parameters after phacoemulsification in rabbits. 总被引:1,自引:0,他引:1
Giovanni Camillieri Annarita Nastasi Pietro Gulino Claudio Bucolo Filippo Drago 《Journal of ocular pharmacology and therapeutics》2004,20(2):151-157
Free-radical formation may play a role in postoperative complications of phacoemulsification (e.g., corneal endothelium damage from mechanical injury). The present experiments were aimed at investigating whether different molecular weight ranges (2000-2600, 2600-3200, or 3200-3800 kDa) of hyaluronan may influence free radical formation, corneal endothelium damage, and inflammation parameters after phacoemulsification in the rabbit eye. The viscoelastic substance was injected in the anterior chamber of rabbits' eyes before phacoemulsification, at a 2.5% concentration. The formation of free radicals was determined by adding luminol to the irrigation media and measuring the chemoluminescence in eyes. The corneal endothelial damage was evaluated by measuring the corneal central thickness by pachimetry. The inflammation parameters were measured by calculation in aqueous humor of peak levels of leukocytes and prostaglandin E(2) (PGE(2)) and evaluation in uveal tissue of myeloperoxidase activity. Hyaluronan decreased by about 58-60% free-radical formation during phacoemulsification, reduced by about 76-80% modifications in mean corneal thickness and by about 54-61% the corneal endothelial cell loss in all molecular weight ranges used. No difference was found among various molecular weight ranges. The highest molecular weight range showed to be more potent than the lowest range for reduced number of inflammation cells and level of PGE(2) in aqueous humor. Thus, hyaluronan reduces free-radical formation, exerts protection on the corneal endothelium and exerts anti-inflammation properties after phacoemulsification in rabbits. The latter effect seems to depend on the molecular weight of the substance. 相似文献
44.
Sports medicine physicians are not exempt from the ethical challenges of medical practice merely because their patients are robust and healthy. In fact, precisely because the patients with sports injuries are so healthy the moral issues remain subtle. Many ethical issues in sports medicine come about because the traditional relationship between doctor and patient is altered or absent. In the current review, several routine topics in biomedical ethics, including doctor and patient confidentiality, informed consent, the care of minors, medical advertising and use of innovative treatments, will be studied from the sports medicine perspective. Hypothetical case histories will be presented, along with an analysis of the underlying ethical issues. The goal of this analysis is not to offer answers to these moral questions, but to increase awareness and promote contemplation of the correct course of action. 相似文献
45.
Andrea Loreti Abate Ornella Floriana Arelli Diana Spallone Edoardo Bruno Pietro De Luca Leopoldo Costarelli Angelo Camaioni 《Clinical Case Reports》2022,10(8)
Mucoepidermoid Carcinoma (MEC) it can origin from a mandibular odontogenic cyst. We report the case of a 63‐year‐old man with MEC of the right retromolar trigonum of the mandibula. We performed a wide mandibular excision and immediate reconstruction with a fibula bone free flap. 相似文献
46.
47.
Gianluca Coppola Ilenia Corbelli Antonio Di Renzo Andrea Chiappiniello Pietro Chiarini Vincenzo Parisi Giorgio Guercini Paolo Calabresi Roberto Tarducci Paola Sarchielli 《The journal of headache and pain》2022,23(1)
IntroductionSeveral functional neuroimaging studies on healthy controls and patients with migraine with aura have shown that the activation of functional networks during visual stimulation is not restricted to the striate system, but also includes several extrastriate networks.MethodsBefore and after 4 min of visual stimulation with a checkerboard pattern, we collected functional MRI in 21 migraine with aura (MwA) patients and 18 healthy subjects (HS). For each recording session, we identified independent resting-state networks in each group and correlated network connection strength changes with clinical disease features.ResultsBefore visual stimulation, we found reduced connectivity between the default mode network and the left dorsal attention system (DAS) in MwA patients compared to HS. In HS, visual stimulation increases functional connectivity between the independent components of the bilateral DAS and the executive control network (ECN). In MwA, visual stimulation significantly improved functional connectivity between the independent component pairs salience network and DAS, and between DAS and ECN. The ECN Z-scores after visual stimulation were negatively related to the monthly frequency of aura.ConclusionsIn individuals with MwA, 4 min of visual stimulation had stronger cognitive impact than in healthy people. A higher frequency of aura may lead to a diminished ability to obtain cognitive resources to cope with transitory but important events like aura-related focal neurological symptoms. 相似文献
48.
Roberto Orecchia Umberto Veronesi Patrick Maisonneuve Viviana Enrica Galimberti Roberta Lazzari Paolo Veronesi Barbara Alicja Jereczek-Fossa Federica Cattani Claudia Sangalli Alberto Luini Pietro Caldarella Marco Venturino Daniele Sances Stefano Zurrida Giuseppe Viale Maria Cristina Leonardi Mattia Intra 《The lancet oncology》2021,22(5):597-608
49.
BACKGROUND: Endometrial ossification is a rare disease. More than 80% of cases occur after pregnancy, but it has been observed in patients with a history of endometritis, dilation and curettage, and metabolic disorders. CASE: A 42-year-old woman presented with osseous metaplasia of both the endometrium and ovaries. At laparoscopy both adnexa were covered with adhesions and were adherent to the posterior wall of the uterus. Following adhesiolysis, calcified nodules were removed from both ovaries with biopsy forceps. Endometrial bone tissue was removed by hysteroscopic resection. CONCLUSION: To our knowledge, this is the first reported case of osseous metaplasia of both the endometrium and ovaries since all cases described to date in the literature involved only the uterine cavity. Conservative management with endoscopic surgery is effective. 相似文献
50.
Gambadauro P Torrejón R 《European journal of obstetrics, gynecology, and reproductive biology》2007,134(2):269-70; author reply 270-1