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1.
The authors retrospectively reviewed the MR examinations of 46 patients with clinical and laboratory findings of monoclonal gammopathies (MG). All cases had been submitted to radiographic examination which had shown skeletal involvement in 22 cases and osteoporosis in 11, with rupture of the vertebral body in 3 patients. Scintigraphy had been performed on all patients and CT on 12; 36 patients were subsequently submitted to follow-up (at 6, 12 and 24 months). MR examinations were performed with dedicated coils and standard sequences for the subjects with skeletal localizations on X-ray images. The extant cases, with no radiographic evidence of skeletal involvement, were submitted to MRI of the spine, skull and pelvis. In agreement with clinical and laboratory findings and with follow-up results (in 36 patients), MRI diagnosed MG with no skeletal involvement in 13 cases, osteoporosis in 8 (with rupture of the vertebral body in 2), asymptomatic non-progressive myeloma in 4, solitary myeloma in 3, and multiple myeloma in 18 cases. The good identification of bone marrow and its multiplanarity make MRI the method of choice in the study of patients with suspected or known gammopathies. If compared with other modalities, MRI is more sensitive and accurate in depicting the tumor, its size and relationship to periskeletal tissues, and its possible multifocality. Moreover, the technique has proven to be a valid tool during the follow-up, showing tumor response to therapy.  相似文献   
2.
The aim of this study was to evaluate the evolution of lumbar disk herniation in patients treated without surgery. Sixty-nine patients with a lumbar disk herniation proved at magnetic resonance (MR) imaging underwent a follow-up MR imaging study. The disk herniations evaluated during both MR imaging examinations were measured and classified into four categories according to the change in size that occurred. The patients were also divided into three clinical classes on the basis of the clinical outcome. Sixty-three percent of the patients showed a reduction of disk herniation of more than 30% (48% had a reduction of more than 70%), while only 8% demonstrated worsening of the clinical picture. These findings suggest that lumbar disk herniation may be primarily a medical (nonsurgical) disease and that MR imaging could play an important role in management of and research into the disorder.  相似文献   
3.
Eighteen patients affected by intra-cranial aneurysms, with size ranging from 3 to 30 mm, were studied by means of MRI, CT, and angiography. MRI was performed using Spin-Echo (SE) sequences with different Repetition Times (TR) and Echo Times (TE), which allowed the characterization of the lesions in relation to the relaxation times. MRI could identify all the aneurysms. In 13 subjects the parent vessels could be seen. In 5 patients the aneurysms could be recognized only after angiography, due to their dimension (less than 4 mm). The "flow effects" and the presence of methemoglobin and hemosiderin in the thrombosed portion of the lumen allowed both the detection of flow abnormalities and the characterization of laminate intra-aneurysmal thrombosis. In conclusion, MRI appears to be a sensitive methodology in the detection of intracranial aneurysms, even more sensitive than CT and Angiography in characterizing this kind of lesions.  相似文献   
4.
A copper-based metal–organic framework (MOF) was prepared using a new linker, a 5-substituted isophthalic acid bearing a propargyl carbamate group, intended to provide a terminal alkyne function protruding from the material surface to generate supported gold species for potential catalytic applications. The novel material was fully characterized by spectroscopic analyses of different kinds: FTIR, Raman, EDX, and XPS, as well as by thermal and surface area measurements. Synchrotron X-ray diffraction data analysis, in particular, revealed that this MOF, labelled [Cu(1,3-YBDC)]·xH2O (x ∼ 2), where Y stands for the pendant alkYne and BDC for benzene dicarboxylate, contains a complex network of 5-substituted isophthalate anions bound to Cu(ii) centers, arranged in pairs within paddlewheel (or “Chinese lantern”) fragments of Cu2(μ-COO)4(D)2 formulation (D being a neutral Lewis base), with a short Cu⋯Cu distance of 2.633(4) Å. Quite unexpectedly, the apical atom in the paddlewheel structure belongs to the carbamate carbonyl oxygen atom. Such extra coordination by the propargyl carbamate groups drastically reduces the MOF porosity, a feature that was also confirmed by BET measurements. However, the MOF functionality is retained at the external crystal surface where 2% of active terminal alkynes is located.

A copper-based metal–organic framework with a novel 5-substituted isophthalic linker bearing a propargyl carbamate group protruding from the material surface.  相似文献   
5.
Zhang J  Masciocchi M  Lewis D  Sun W  Liu A  Wang Y 《Placenta》2008,29(5):439-443
The etiology and pathophysiology of preeclampsia are not fully understood. However, oxidative stress has been strongly linked to the occurrence of this multi-system disease. This has led to many theories of the pathogenesis of preeclampsia involving placental oxidative stress. In this study, we hypothesized that polymorphisms of anti-oxidant genes in the placental tissue contributed to susceptibility to preeclampsia. Polymorphisms in copper/zinc superoxide dismutase (CuZn-SOD), manganese superoxide dismutase (MnSOD), glutathione-S-transferase M1 (GSTM1), and glutathione-S-transferase T1 (GSTT1) in the umbilical cord tissue were assayed by polymerase chain reaction (PCR) in 23 nulliparous preeclampsia cases and 32 nulliparous normotensive controls. Corresponding enzyme activity levels and an oxidative stress biomarker (8-isoprostane) of the placental tissue were also measured. In addition, maternal plasma 8-isoprostane levels were also determined. Our results showed that no significant differences in polymorphism frequency of the tested genes, enzyme activity levels or 8-isoprostane levels in the placental tissue were detected between the cases and controls. However, maternal plasma 8-isoprostane level was significantly higher in the cases than in the controls (105.8 vs. 27.9 pg/ml, p=0.03). In conclusion, our study showed that polymorphisms of CuZn-SOD, MnSOD, GSTM1 and GSTT1 in the placental tissue were not associated with preeclampsia.  相似文献   
6.
Purpose: To verify the diagnostic potentialities of conventional magnetic resonance imaging (MRI), breath-hold 3D contrast enhanced MR angiography (C3D MRA) and transesophageal echocardiography (TEE) in patients surgically treated for type A aortic dissection. Materials and methods: Twenty-nine patients (21 males and 8 females), surgically treated for type A aortic dissection, were evaluated with MRI using a 1.5 T (GE Horizon Echospeed 8.2) with standard gated SE sequences and breath-hold 3D fast SPGR after intravenous Gd injection (0.2 mmol/kg). 3D MIP reconstruction was obtained. TEE evaluation was performed with a HP 2000 system and a biplane 5 MHz probe. The sizes of aortic root, distal anastomosis, descending aorta and periprosthetic thickening were measured. Regional false lumen and aortic branch involvement were also evaluated. Results: Concordance among TEE, conventional MRI and C3D MRA was observed in the evaluation of aortic root (MRI vs. C3D MRA r = 0.93; MRI vs. TEE r = 0.84; C3D MRA vs. TEE r = 0.84) and descending aorta (r = 0.94, 0.91 and 0.92, respectively). The interobserver variability was also very low. Inadequate agreement was observed for distal anastomosis. C3D MRA was inadequate in the evaluation of periprosthetic thickening; r = 0.73 was obtained between MRI and TEE. For qualitative data: TEE was inadequate in the evaluation of the abdominal aorta and branches. C3D MRA depicted supra-aortic vessel involvement in more cases than the other techniques. Conclusion: C3D MRA is a fast and accurate technique in the evaluation of the endoluminal alterations and involvement of the aortic branches. Conventional MRI allows a direct evaluation of the aortic wall and periaortic tissue. TEE is less accurate in the evaluation of aortic branches and abdominal aorta.  相似文献   
7.
Purpose: To verify the diagnostic potentialities of conventional magnetic resonance imaging (MRI), breath-hold 3D contrast enhanced MR angiography (C3D MRA) and transesophageal echocardiography (TEE) in patients surgically treated for type A aortic dissection. Materials and methods: Twenty-nine patients (21 males and 8 females), surgically treated for type A aortic dissection, were evaluated with MRI using a 1.5 T (GE Horizon Echospeed 8.2) with standard gated SE sequences and breath-hold 3D fast SPGR after intravenous Gd injection (0.2 mmol/kg). 3D MIP reconstruction was obtained. TEE evaluation was performed with a HP 2000 system and a biplane 5 MHz probe. The sizes of aortic root, distal anastomosis, descending aorta and periprosthetic thickening were measured. Regional false lumen and aortic branch involvement were also evaluated. Results: Concordance among TEE, conventional MRI and C3D MRA was observed in the evaluation of aortic root (MRI vs. C3D MRA r = 0.93; MRI vs. TEE r = 0.84; C3D MRA vs. TEE r = 0.84) and descending aorta (r = 0.94, 0.91 and 0.92, respectively). The interobserver variability was also very low. Inadequate agreement was observed for distal anastomosis. C3D MRA was inadequate in the evaluation of periprosthetic thickening; r = 0.73 was obtained between MRI and TEE. For qualitative data: TEE was inadequate in the evaluation of the abdominal aorta and branches. C3D MRA depicted supra-aortic vessel involvement in more cases than the other techniques. Conclusion: C3D MRA is a fast and accurate technique in the evaluation of the endoluminal alterations and involvement of the aortic branches. Conventional MRI allows a direct evaluation of the aortic wall and periaortic tissue. TEE is less accurate in the evaluation of aortic branches and abdominal aorta.  相似文献   
8.
Objectives. Interstitial lung disease (ILD) profoundly affectsthe health-related quality of life (HRQoL) in patients withsystemic sclerosis (SSc). We tested the validity of the SaintGeorge's Respiratory Questionnaire (SGRQ), a lung-specific HRQoL-evaluationtool, in a population of SSc patients with ILD. Methods. Twenty-eight consecutive SSc patients with a restrictivepulmonary involvement, defined as a forced vital capacity <80%of the predicted, with no pulmonary hypertension were considered.All the patients filled in the Medical Research Council (MRC)scale for perceived breathlessness, the SGRQ and the DisabilityIndex of the Health Assessment Questionnaire (HAQ DI), and underwentevaluation with complete pulmonary function testing (PFT), 6-minutewalk distance (6MWD) and high-resolution computed tomography(HRCT). Results. The SGRQ ‘activity’ scores inversely correlatedwith the 6MWD (r = –0.86, P < 0.001) and forced vitalcapacity percentage of predicted values (r = –0.47) anddirectly correlated with HRCT (r = 0.41, P < 0.05), MRC (= 0.64, P < 0.001) or HAQ DI scores (r = 0.62, P < 0.001),independently of disease duration or subset. On the contrary,HAQ DI scores were influenced by those variables and correctedcorrelations with 6MWD (r = 0.56, P < 0.001) or HRCT scores(r = 0.36, P = NS) were less strong than those observed withthe SGRQ. Conclusions. The SGRQ, although not specifically designed forscleroderma, is a valid respiratory-specific questionnaire forthe evaluation of HRQoL in patients with SSc-related ILD. TheSGRQ performs better in relation to exercise capacity and lungimaging than other non-respiratory-specific questionnaires widelyused in scleroderma studies. Further studies are needed to addressits ability to assess changes over time or in response to therapy. KEY WORDS: Systemic sclerosis, Quality of life, Interstitial lung disease Submitted 22 March 2006; revised version accepted 19 May 2006.  相似文献   
9.
PURPOSE: Our study aimed to assess the role of magnetic resonance imaging (MRI) in the characterisation of musculoskeletal tumours and to identify specific perfusion patterns for the different tumours. MATERIALS AND METHODS: Between January 2003 and September 2005, we evaluated the conventional and perfusion MRIs of 39 patients with musculoskeletal tumours. Dynamic MRI was performed with a 1.5-T and 1.0-T MRI unit before and after the intravenous administration of contrast material, using dedicated phased-array coils appropriate for the region to be studied and fast and ultrafast consecutive sequences. Postprocessing was done on an independent workstation (Advantage Windows, GE Medical System), with Functool (GE) software, which allowed a quantitative evaluation of enhancement as a function of time. The results were compared with the histopathological diagnoses obtained by biopsy or surgery. RESULTS: The lesions identified in the 39 patients included 23 soft tissue tumours (12 benign, 11 malignant) and 16 bone tumours (ten benign, six malignant). Comparing the time-intensity diagrams of lesions of the same histological type, we found typical enhancement patterns for some bone tumours only, especially for bone, cartilaginous, fibrohistiocytic and pseudoinflammatory lesions. No typical enhancement pattern could be detected for any of the histological types of soft tissue tumour. Analysis of the slope of the time-intensity curves has a sensitivity and specificity of 64%-58% for soft tissue tumours and 86%-67% for bone tumours in determining the biological aggressiveness of the lesions. CONCLUSIONS: Perfusion MRI had moderate sensitivity and specificity in the differential diagnosis between lesions with high or low biological activity. Only in a few cases was it possible to find some correlation between perfusion patterns and lesion histology. The slope values should therefore be used in combination with conventional spin-echo images and other imaging and clinical data in order to narrow the field of the possible differential diagnoses and reliably predict the nature of the lesion.  相似文献   
10.
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