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81.
This paper summarizes the value of diffusion-weighted magnetic resonance imaging in the evaluation of temporal bone pathology. It highlights the use of different types of diffusion-weighted magnetic resonance imaging in the different types of cholesteatoma, prior to first stage surgery and prior to second look surgery. The value of diffusion-weighted magnetic resonance imaging in the evaluation of pathology of the apex of the petrous bone and the cerebellopontine angle is also discussed.  相似文献   
82.
Uterine artery embolization using non spherical PVA particles or calibrated trisacryl microspheres above 500 μm is effective to treat menorrhagia, bulk-related symptoms and pelvic pain in more than 90% of cases in the short-term. In the long-term, embolization is effective in 75% of cases at 5-7 years. At 6 months, uterine volume reduction and dominant fibroid volume reduction varies between 30-60% and 50-80% respectively. During hospital stay, the complication rate is 3%. Secondary hysterectomy for complication is less than 2% at 3 months. Definitive amenorrhea is reported in less than 5% of cases in women of less than 45 years of age. No significant impact of embolization on hormonal function has been reported in women less than 45 years with normal baseline function. Secondary hysterectomy for clinical failure or recurrence is reported in 14-28% of cases at 5 years. Non-spherical PVA particles are associated with more microcatheter occlusion than trisacryl microspheres. No difference between PVA particles and trisacryl microspheres was found in terms of post-embolization pain or analgesic doses. PVA microspheres (Contour SE et Bead Block) are associated with lower clinical success and lower fibroid devascularization using MRI than trisacryl microspheres. No difference between PVA particles and trisacryl microspheres was found in terms of clinical efficacy, uterine volume reduction and complication rate. Randomized studies comparing embolization to hysterectomy demonstrate that reinterventions are more frequently performed after embolization. Secondary hysterectomy is performed in 13 to 24% of cases at 2 years and in up to 28% of cases at 5 years. Hospital stay, duration of recovery and time off work are shorter after embolization compared to hysterectomy. Embolization is cheaper than hysterectomy at 12 and 24 months even taking into consideration the additional costs of imaging and reinterventions. Randomized studies comparing embolization to myomectomy demonstrate that in the short- and mid-term there is no difference in terms of control of menorrhagia and bulk-related symptoms. Uterine volume reduction and quality of life were not different at 6 months. Periprocedural and 30-day complication rates are not different. At 6 months, the rate of complications is higher after myomectomy. Reinterventions are more frequent after embolization compared to myomectomy. Hospital stay, duration of recovery and time off work are shorter after embolization compared to myomectomy. Embolization should be considered with caution in pregnancy-seeking women since there is still a lack of good quality data available in the specific group of patients. FSH level is more frequently elevated after embolization compared to myomectomy. Pregnancy rate and term pregnancy rate are higher after myomectomy compared to embolization. Spontaneous abortion is more frequent after embolization than after myomectomy. There is no difference between embolization and myomectomy for the rates of pre-term delivery, cesarean section, post-partum hemorrhage, pre-eclampsia or intra-uterine growth retardation. Embolization performed before myomectomy (preoperative or combined procedures) can be discussed for an individual patient but there is not enough data to support its routine use.  相似文献   
83.
Intrahepatic lymphocytes are believed to be involved in the immunopathogenesis of hepatitis C virus (HCV) infection and the evolution of HCV-induced hepatitis. In the present study, we examined the three main intrahepatic lymphocyte subsets, namely CD3+CD56- conventional T lymphocytes, CD3+CD56+ natural T (NT) lymphocytes and CD3-CD56+ natural killer (NK) lymphocytes in HCV-infected patients. The proportion of each lymphocyte subset was evaluated both in liver biopsies and in samples of peripheral blood lymphocytes (PBL) by flow cytometry in 21 patients with histologically proven chronic hepatitis C. Simultaneously, alanine aminotransferase (ALT) levels, viral load and histological lesions were assessed. Neither NT nor NK populations correlated with any biochemical, viral or histological parameters. Furthermore, Valpha24+ NT lymphocytes showed no preferential enrichment in the liver of HCV-infected patients. Regarding conventional T lymphocytes, a highly significant linear correlation was found between intrahepatic CD3+CD56- T lymphocytes and the Knodell score, a numerical score for assessing histological activity and fibrosis (r = 0.715, P < 0.0001) and more specifically with the periportal necrosis parameter, which is the main lesion of chronic hepatitis C. In addition, analysis of the peripheral compartment revealed a high correlation between values of CD3+CD56- lymphocytes and both Knodell score (r = 0.624, P = 0.003) and serum ALT levels and again with periportal necrosis. The strong correlation between the proportion of peripheral CD3+CD56- conventional T lymphocytes and the severity of hepatic lesions leads us to propose that evaluation of this accessible peripheral population could be used as an indicator test for the severity of histological lesions in chronic hepatitis C. Abbreviations:  相似文献   
84.
Isolated porcine pulmonary vessels were studied in order to evaluate the role of nitric oxide in arteries and veins. Leukotriene C4 and noradrenaline contracted porcine pulmonary arteries but induced only negligible contractions of porcine pulmonary veins. After treatment with the nitric oxide synthase inhibitor N(omega)-nitro-L-arginine (L-NOARG), significant contractions to leukotriene C4 and noradrenaline were uncovered in pulmonary veins. In arterial preparations, L-NOARG caused a less marked potentiation of noradrenaline-induced contractions and did not alter leukotriene C4-induced contractions. Endothelium-dependent relaxations to acetylcholine were greater in veins compared with arteries whereas the endothelium-independent relaxations to the nitric oxide donor sodium nitroprusside (SNP) and the cyclic nucleotide analogue 8-bromo-cGMP were similar in the two preparations. Taken together these data suggest that the apparent insensitivity of porcine pulmonary veins to leukotriene C4 and noradrenaline was because of release of nitric oxide. The effect of nitric oxide synthase inhibition was less pronounced in porcine pulmonary arteries, suggesting a preferential functional role of nitric oxide in porcine pulmonary veins, originating in a greater production of nitric oxide by veins as opposed to arteries.  相似文献   
85.
Systemic lupus erythematosus (SLE) is a prototypical autoimmune disease characterized by polyclonal B cell activation and by the production of anti-double-stranded (ds) DNA antibodies. Given the inhibitory effects of IL-12 on humoral immune responses, we investigated whether IL-12 displayed such an activity on in vitro immunoglobulin production by SLE PBMC. Spontaneous IgG, IgG1, IgG2, IgG3 and IgM antibody production was dramatically reduced by addition of IL-12. These results were confirmed by Elispot assays detecting IgG- and anti-dsDNA-secreting cells. While IL-6 and TNF titres measured in PBMC supernatants were not modified by addition of IL-12, interferon-gamma (IFN-γ) titres were up-regulated and IL-10 production down-regulated. Since addition of IFN-γ did not down-regulate immunoglobulin production and since the inhibitory activity of IL-12 on immunoglobulin synthesis was not suppressed by anti-IFN-γ antibody, we concluded that the effect of IL-12 on immunoglobulin production was not mediated through IFN-γ. Our data also argue against the possibility that down-regulation of endogenous IL-10 production was responsible for the effect of IL-12. Thus, inhibition of IL-10 production by IFN-γ was not accompanied by inhibition of immunoglobulin production, and conversely, restoration of IL-10 production by anti-IFN-γ antibody did not suppress the inhibitory activity exerted by IL-12 on immunoglobulin production. Taken together, our data indicate that reduction of excessive immunoglobulin and anti-dsDNA antibody production by lupus PBMC can be achieved in vitro by IL-12, independently of IFN-γ and IL-10 modulation.  相似文献   
86.
87.

Background

Chromosomal abnormalities are a major cause of mental retardation and multiple congenital anomalies (MCA/MR). Screening for these chromosomal imbalances has mainly been done by standard karyotyping. Previous array CGH studies on selected patients with chromosomal phenotypes and normal karyotypes suggested an incidence of 10–15% of previously unnoticed de novo chromosomal imbalances.

Objective

To report array CGH screening of a series of 140 patients (the largest published so far) with idiopathic MCA/MR but normal karyotype.

Results

Submicroscopic chromosomal imbalances were detected in 28 of the 140 patients (20%) and included 18 deletions, seven duplications, and three unbalanced translocations. Seventeen of 24 imbalances were confirmed de novo and 19 were assumed to be causal. Excluding subtelomeric imbalances, our study identified 11 clinically relevant interstitial submicroscopic imbalances (8%). Taking this and previously reported studies into consideration, array CGH screening with a resolution of at least 1 Mb has been undertaken on 432 patients with MCA/MR. Most imbalances are non‐recurrent and spread across the genome. In at least 8.8% of these patients (38 of 432) de novo intrachromosomal alterations have been identified.

Conclusions

Array CGH should be considered an essential aspect of the genetic analysis of patients with MCA/MR. In addition, in the present study three patients were mosaic for a structural chromosome rearrangement. One of these patients had monosomy 7 in as few as 8% of the cells, showing that array CGH allows detection of low grade mosaicisims.  相似文献   
88.
Malignant non-Wilms renal tumors (NWRT) are a small but relevant subgroup of renal neoplasms in children. In this study we analyzed corresponding data from the trials SIOP 93-01/GPOH and SIOP 2001/GPOH of the Society of Pediatric Oncology and Hematology.Data of 22 patients with NWRT and primary lung metastases were retrospectively reviewed. Analyses included epidemiology, tumor characteristics, chemotherapy, local treatment, and outcome.The following diagnoses were registered: Malignant Rhabdoid tumor of the kidney (MRTK, n=15), Renal-cell carcinoma (RCC, n=3), Clear-cell sarcoma of the kidney (CCSK, n=3), and primitive neuro ectodermal tumor (PNET, n=1). Median age of patients at diagnosis was 14 months. Overall survival was 36.36% (8/22). Of the 15 children with MRTK 3 survived, 3/3 patients with RCC, 1/3 patients with CCSK, and 1/1 patient with PNET survived. Lung metastases disappeared in 6 patients after initial chemotherapy, 6/8 patients undergoing local treatment of lung metastases (surgery, irradiation, or both) achieved complete remission. Only patients with complete clearance of lung lesions, either through neoadjuvant chemotherapy or subsequent local treatment, survived. Mean Follow up was 31 months (1-137).Survival of patients with stage IV NWRT is dismal. Complete removal of lung metastases seems mandatory for survival. An aggressive diagnostic and therapeutic approach seems justified in affected children.  相似文献   
89.
BACKGROUND: The allergic rhinitis and its impact on asthma (ARIA) guidelines provide a new classification of allergic rhinitis, but a quantitative analysis for severity assessment is lacking. OBJECTIVE: To study whether a visual analog scale (VAS) for global rhinitis symptoms could be used to assess the disease severity according to ARIA. METHODS: Three thousand fifty-two allergic rhinitis patients seen in primary care were tested. Fifty three per cent had an objective diagnosis of allergy and 58% of the patients were treated. Patients were categorized according to ARIA guidelines. The severity of nasal symptoms was assessed using a VAS. Quality of life was measured using the rhinoconjunctivitis quality of life questionnaire (RQLQ). RESULTS: Severity had more impact on VAS levels than duration: mild intermittent rhinitis (3.5, 2.4-5.0 cm), mild persistent rhinitis (4.5, 3.2-5.6 cm), moderate/severe intermittent rhinitis (6.7, 5.3-7.7 cm) and moderate/severe persistent rhinitis (7.2, 6.1-8.2 cm). The receiver operating characteristic curve results showed that patients with a VAS of under 5 cm could be classified as 'mild' rhinitis (negative predictive value: 93.5%) and those with a VAS of over 6 cm as 'moderate/severe' rhinitis (positive predictive value: 73.6%). Receiver operating characteristic curves and a logistic regression showed that current treatment and allergy diagnosis have no effect on the assessment of rhinitis severity using VAS. Visual analog scale and the RQLQ global score were significantly correlated (rho = 0.46; P < 0.0001). CONCLUSION: A simple and quantitative method (VAS) can be used for the quantitative evaluation of severity of allergic rhinitis.  相似文献   
90.
Cell trafficking into the rheumatoid synovium is thought to play an important role in the inflammation seen in rheumatoid arthritis. Chemokine receptors play a central role in this process, and several common variants are known, including the CCR2 variant, CCR2-64I, and two variants of the CX3CR1 gene, V249I and T280M. All three variants result in functional amino acid substitutions. We studied the association of these chemokine receptor variants with susceptibility to and severity of rheumatoid arthritis in two Dutch patient populations; 282 consecutive rheumatoid arthritis patients from a rheumatology outpatient clinic, and a cohort of 101 female rheumatoid arthritis patients, followed closely for a 12-year period, from whom hand and feet X-rays taken at three year intervals were scored and analyzed in this study. Although there was a trend towards increased severity of disease in patients carrying CX3CR1 variants, this was not independent of known risk factors. We found no evidence for a significant independent role for the CCR2 and CX3CR1 variants in the susceptibility to or severity of rheumatoid arthritis.  相似文献   
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