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81.
A Manrique M Faraggi P Véra D Vilain R Lebtahi A Cribier D Le Guludec 《Journal of nuclear medicine》1999,40(5):805-809
Left ventricular ejection fraction (LVEF) is a major prognostic factor in coronary artery disease and may be computed by 99mTc-methoxyisobutyl isonitrile (MIBI) gated SPECT. However, 201Tl remains widely used for assessing myocardial perfusion and viability. Therefore, we evaluated the feasibility and accuracy of both 99mTc-MIBI and 201Tl gated SPECT in assessing LVEF in patients with myocardial infarction, large perfusion defects and left ventricular (LV) dysfunction. METHODS: Fifty consecutive patients (43 men, 7 women; mean age 61 +/- 17 y) with a history of myocardial infarction (anterior, 26; inferior, 18; lateral, 6) were studied. All patients underwent equilibnum radionuclide angiography (ERNA) and rest myocardial gated SPECT, either 1 h after the injection of 1110 MBq 99mTc-MIBI (n = 19, group 1) or 4 h after the injection of 185-203 MBq 201Tl (n = 31, group 2) using a 90 degrees dual-head camera. After filtered backprojection (Butterworth filter: order 5, cutoff 0.25 99mTc or 0.20 201Tl), LVEF was calculated from reconstructed gated SPECT with a previously validated semiautomatic commercially available software quantitative gated SPECT (QGS). Perfusion defects were expressed as a percentage of the whole myocardium planimetered by bull's-eye polar map of composite nongated SPECT. RESULTS: Gated SPECT image quality was considered suitable for LVEF measurement in all patients. Mean perfusion defects were 36% +/- 18% (group 1), 33% +/- 17% (group 2), 34% +/- 17% (group 1 + group 2). LVEF was underestimated using gated SPECT compared with ERNA (34% +/- 12% and 39% +/- 12%, respectively; P = 0.0001). Correlations were high (group 1, r= 0.88; group 2, r = 0.76; group 1 + group 2, r = 0.82), and Bland-Altman plots showed a fair agreement between gated SPECT and ERNA. The difference between the two methods did not vary as LVEF, perfusion defect size or seventy increased or when the mitral valve plane was involved in the defect. CONCLUSION: LVEF measurement is feasible using myocardial gated SPECT with the QGS method in patients with large perfusion defects and LV dysfunction. However, both 201Tl and 99mTc-MIBI gated SPECT similarly and significantly underestimated LVEF in patients with LV dysfunction and large perfusion defects. 相似文献
82.
Tracheobronchial injuries following blunt chest trauma are rare and can be lethal. CT scan can help to diagnose it when a defect to the tracheobronchial wall is visible or to suspect it in front of indirect signs. 相似文献
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85.
Rammeh-Rommani S Zermani R Zouari B Sfaxi M Chabchoub A Farah F Kourda N Ayed M Ben Jilani S 《La Tunisie médicale》2005,83(12):746-749
OBJECTIVE: To study, through a series of superficial bladder tumors, the prognostic factors of recurrence and tumoral progression. MATERIALS AND METHODS: This is a retrospective study of a series of 59 urothelial tumors of the bladder at stage pTa or pT1. The following parameters were considered: age, sex, treatment, stage and grade. The chi square test was used in search of a correlation between the different parameters and the course (recurrence and progress) of the disease. A multivariate analysis was undertaken by integrating factors correlated with the course. RESULTS: Thirty two tumors (54 %) had recured versus 27 (46%) without recurrence. Eight tumors (25 %) progressed in grade and 4 (12,5 %) had become infiltrative. Age beyond 65 years, tumoral size > 3 cm and multifocality were predictive factors of recurrence with a relative risks of 2,36, 3,28 and 3,88 respectively. In a multivariate analysis, these factors remained significant with adjusted relatif risks respectively of 1,36, 1,6 and 1,7. 相似文献
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87.
Nachat R Méchin MC Charveron M Serre G Constans J Simon M 《The Journal of investigative dermatology》2005,125(1):34-41
Peptidylarginine deiminases (PAD) catalyze the conversion of arginine residues to citrullines. Five isoforms are known that present distinct tissue locations. In the epidermis, like in the skin, only PAD1, 2, and 3 are expressed. Their pattern of expression in skin appendages is not known. Here, confocal microscopy analysis using highly specific antibodies demonstrated that PAD1 and 3 are expressed in human anagen hair follicles, PAD1 and 2, in arrector pili muscles and sweat glands, whereas no PAD were detected in sebaceous glands. PAD1 was detected in the cuticle and the Huxley layer of the inner root sheath (IRS), and in the companion layer. PAD3 was localized in the medulla, and in the three layers of the IRS. Using anti-modified citrulline antibodies, we also showed that deiminated proteins appeared in the lower part of the IRS, first in the Henle layer, then in the cuticle, and finally in the Huxley layer. Our data demonstrate that PAD3 is the enzyme that deiminates trichohyalin in the medulla and the Henle layer, indicate that PAD1 and 3 are involved in the hair follicle program of differentiation, and suggest a role for PAD1 and 2 in the physiology of sweat glands and arrector pili muscles. 相似文献
88.
Developmental expression of genes involved in neurosteroidogenesis: 3beta-hydroxysteroid dehydrogenase/delta5-delta4 isomerase in the rat brain 总被引:3,自引:0,他引:3
Ibanez C Guennoun R Liere P Eychenne B Pianos A El-Etr M Baulieu EE Schumacher M 《Endocrinology》2003,144(7):2902-2911
In the central nervous system, neurosteroids, in particular progesterone, have neurotrophic and neuroprotective effects. We thus decided to study the developmental expression of 3beta-hydroxysteroid-dehydrogenase/Delta(5)-Delta(4) isomerase (3betaHSD), an enzyme that converts pregnenolone to progesterone, in the male rat brain at 0, 7, 14, and 70 d after birth. 3betaHSD mRNA was widely distributed throughout the brain, as shown by in situ hybridization. At all ages, the same cerebral structures were labeled, but the intensity of the hybridization signal constantly decreased during postnatal development. As the hippocampus is of particular interest because of its neuronal plasticity, we chose to quantify the changes in 3betaHSD mRNA levels as well as progesterone and pregnenolone concentrations in this structure. Quantitative in situ hybridization confirmed a decrease in the expression of 3betaHSD mRNA with progressing age, as revealed by a significant reduction in the density of silver grains per cell in the CA1 layer. This decrease was confirmed by semiquantitative RT-PCR on hippocampal samples. Concentrations of hippocampal pregnenolone and progesterone measured by gas chromatography/mass spectrometry were highest on the day of birth and lower at the other ages. Plasma concentrations of these steroids were lower than those in the hippocampus, suggesting that they may have been mostly synthesized in situ since the day of birth. These results demonstrate variations in the expression of a gene coding for an enzyme critically involved in progesterone synthesis in the hippocampus throughout postnatal development. 相似文献
89.
Inaoui R Petit B Jaccard A Bertin P Trèves R 《Joint, bone, spine : revue du rhumatisme》2003,70(1):64-66
Systemic mastocytosis is a rare and occasionally aggressive condition that raises major diagnostic challenges. We report a case in a 72-year-old patient in whom the diagnosis of malignant mastocytosis required two bone marrow smears and three bone marrow biopsies examined using specific staining techniques. Despite interferon therapy, a mast-cell sarcoma of the sternum developed 1 year after symptom onset, followed 1 year later by acute myeloblastic leukemia, which was rapidly fatal. 相似文献
90.
Sarda-Mantel L Hervatin F Michel JB Louedec L Martet G Rouzet F Lebtahi R Merlet P Khaw BA Le Guludec D 《European journal of nuclear medicine and molecular imaging》2008,35(1):158-165
Objectives Phosphatidylserin exposure on cell surfaces occurs early during apoptosis and is detected in vivo by using 99mTc-annexin-V (ANX). Cardiomyocyte membrane disruption is detected in vivo by using 111In-antimyosin-antibodies (AM). We aimed to determine if ANX and AM allow evaluation of the time-course of these two distinct
cell death events after myocardial ischemia-reperfusion.
Methods Coronary tying (20 min) followed by reperfusion (IR) was performed in 31 rats. Twelve of the rats were injected with ANX,
11 with AM, and eight with both tracers. Myocardial uptake of tracers was studied 1–2 h, 4 h, or 24 h after IR by scintigraphy
(ANX, n = 14) and autoradiography (all cases), and compared to histology and Apostain staining.
Results Scintigraphy was positive in all rats 2 h after IR and in three of five rats at 24 h. On autoradiography, ANX activity was
intense in myocardial lesions as early as 1 h post-IR, whereas AM activity was mild at 2 h then increased at 4 h post-IR.
ANX and AM uptakes evolved from mid-myocardium to endocardial and epicardial regions from 2 h to 24 h post-IR. Apostain staining
was significant in myocardial lesions (p < 106 compared to six sham-operated rats). On histology, myocardial lesion was characterized by interstitial oedema, myocytes necrosis,
and dramatic thinning at 24 h.
Conclusion These data suggest that ANX and AM allow temporal and regional evaluations of PS exposure and membrane disruption, respectively,
during myocytes death after 20-min myocardial ischemia followed by reperfusion. Also, (i) apoptosis starts very early in injured
myocardium, (ii) myocyte necrosis occurs later (3–4 h post-reperfusion), and (iii) most dead cells are removed from mid-myocardium
between 6 h and 24 h after reperfusion. 相似文献