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21.
Chromosomal rearrangements of the MYC locus, which often involve the IG loci, are recurrent events in multiple myeloma (MM) and plasma cell leukemia (PCL). We used dual-color fluorescence in situ hybridization (FISH) to characterize the breakpoint locations of chromosomal translocations/rearrangements involving the MYC locus at 8q24 found in a panel of 14 MM cell lines and 70 primary tumors (66 MM and 4 PCL). MYC locus alterations were observed in 21 cases: MYC/IG (mainly IGH@) fusions in 11 cell lines and three patients (2 MM and 1 PCL), and extra signals and/or abnormal MYC localizations in seven patients (5 MM and 2 PCL). Fourteen of these cases were investigated by FISH analyses by use of a panel of BAC clones covering about 6 Mb encompassing the MYC locus. The breakpoints were localized in a region 100-250 kb centromeric to MYC in four cases, a region 500-800 kb telomeric to the gene in four cases, and regions > or = 2 Mb centromeric or telomeric to MYC in five cases. Two different breakpoints were detected in the KMS-18 cell line, whereas the insertion of a MYC allele was found in a complex t(16;22) chromosomal translocation in the RPMI8226 cell line. Our data document a relatively high dispersion of 8q24 breakpoints in MM.  相似文献   
22.
Several investigators have described the altered sleep patterns in Down's syndrome subjects. The most relevant findings have been a reduction in percentage of REM sleep, a prolonged latency to the first REM episode, an increase in undifferentiated sleep, and a reduced ratio of the oculomotor frequencies. Because it is of interest to identify new drugs able to increase the percentage of REM sleep in mentally retarded subjects, we studied the effects of butoctamide hydrogen succinate (BAHS) on nocturnal sleep in eight young institutionalized Down's syndrome subjects.BAHS produced a significant increase in the percentage of REM sleep as well as a decrease in undifferentiated sleep and latency to the first REM.  相似文献   
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Cultured, allogenic, human epidermal grafts have been successfully used to treat extensive burns, donor sites, leg ulcers, and eroded areas in recessive dystrophic epidermolysis bullosa. The following report describes the use of cryopreserved cultured human epidermal allografts in the treatment of long-standing ischemic ulcers unresponsive to conventional medical therapy in two patients who had previously undergone unsuccessful vascular reconstructive surgery. A marked reduction in ulcer size as well as rapid pain relief was achieved in both patients. In selected cases the use of epidermal grafts as a biologic topical therapy could represent an alternative to other medical treatments. However, thus far, only a few cases have been reported and the uncertain short- and long-term results as well as the excessive costs may limit the widespread application of this treatment modality.  相似文献   
25.
We present a model to estimate the infection curve of the human immunodeficiency virus in intravenous drug users in Lombardia. We based estimates on AIDS incidence data, according to a backcalculation model accounting for therapy and changes in the surveillance definition of AIDS.  相似文献   
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· Background: The aim of this study was to evaluate the focal electroretinogram (FERG), an objective indicator of outer retinal function, in nonexudative age-related macular degeneration (NE-AMD), and to compare FERG results with morphological lesions assessed by stereoscopic fundus photographs and fluorescein angiograms. · Methods: Twenty-five patients (25 eyes) with bilateral NE-AMD (visual acuity of the study eyes ≥0.4) as well as 10 age- and sex-matched control subjects (10 eyes) were evaluated. FERGs were recorded from the macular region (9°) in response to sinusoidal stimuli flickered at 32 Hz. Amplitude and phase angle of the Fourier-analyzed FERG fundamental component were measured. Fundus lesions were graded from color slides according to the Wisconsin age-related maculopathy grading system [15]. Fluorescein angiograms were evaluated by an image analysis technique to compute the area with pathological hyperfluorescence (associated with drusen and/or retinal pigment epithelial atrophy) within the macular (approximately 9°×9°) region. · Results: Compared to control eyes, NE-AMD eyes had a reduction in the mean FERG amplitude (57% loss, P<0.001) with no phase changes. Amplitudes of individual affected eyes were negatively correlated with either the Wisconsin grading score (r=–0.63, P<0.001) or the percentage area of pathological hyperfluorescence (r=–0.70, P<0.01). Eyes with minimal NE-AMD lesions (Wisconsin score ≤6) and normal acuity had a lower mean amplitude (47% loss, P<0.05) than that of control eyes. · Conclusions: The results indicate that, in NE-AMD, the FERG is altered in parallel with the extent and severity of fundus lesions. However, a functional impairment of outer macular layers, which is detected by FERG losses, could precede morphological changes typical of more advanced disease. Received: 6 March 1998 Revised version received: 5 June 1998 Accepted: 17 June 1998  相似文献   
28.
In our Institute we have performed 124 vertical banded gastroplasties. Patients with a follow-up beyond 3 months were studied with a barium meal, in order to evaluate the efficiency of surgery and the eventual complications. Seventy-nine patients have had one or more X-ray investigations at various times after surgery (for a total of 136 studies). The first 20 patients were routinely studied at 1, 2 and 3 years after the operation; the next 32 patients were studied for features such as vomiting, poor weight loss or low food intake; the last 27 patients were studied with an early overlook beginning 3 months after surgery. We noted gastroesophageal reflux in eight (10.1%) cases, outlet dilatation in four (5%) cases, outlet substenosis (diameter 6-8 mm) in 13 (16.4%) cases, outlet stenosis (diameter ≤5 mm) in four (5%) cases, peanut-type deformation in three (3.7%) cases, and staple-line disruption in 17 (21.5%) cases. The staple-line disruption was correlated in the first part of the series with a reinforcement of such a suture, while the last 27 patients, with vertical stapling carried out with a 4-row stapler without reinforcement, did not present any disruption. The radiographic examination gives information about weight loss and side effects.  相似文献   
29.
Nimesulide release from micronized and unmicronized drug particles was tested at pH 7.4 by measuring the transfer to dimyristoylphosphatidylcholine liposomes (multilamellar and unilamellar vesicles), chosen as a biomembrane model. The perturbing effect of increasing molar fractions of pure nimesulide on the thermotropic behaviour of dimyristoylphosphatidylcholine liposomes was investigated by differential scanning calorimetry. In order to study the drug dissolution process by its uptake into void liposomes, measurements were carried out on suspensions of blank liposomes added to weighed amounts of free powdered nimesulide (micronized and unmicronized). The amount of drug transferred was quantified by comparing the effect caused by the dissolved and released drug to that caused by the free drug that had been previously molecularly dissolved in the liposomes. The calorimetric results show that the dissolution rate depends on the nimesulide form (micronized or unmicronized), and that the transfer to the void liposomes is quicker when the drug is in a micronized form. The uptake was faster when unilamellar vesicles were used instead of multilamellar vesicles because of the greater lipid surface. The calorimetric technique could represent an alternative 'in vitro' method that can be applied to the study of the dissolution kinetics directly at the site of drug uptake, mimicking a biological system.  相似文献   
30.
It is currently accepted that vinil infections may influence the development of atopy. In the present study we evaluated serum IgE levels as well as the prevalence of symptom-, indicative of utopic disease and EBV antibodies in 353 children aged from I month to 19 years. Antibodies against EBV were detected by immunofluorescence. IgE levels in serum were measured by en/. yme imimmoassay. Dividing ihe study population according to EBV seropositivity and age, we noted that the prevalence of high IgE levels (> 2 s. d.) was, in total, more frequent in the EBV negative (32. 9%) than in the positive subjects (27. 6%). Interestingly, this higher prevalence was found only in the groups aged under six, especially in the 7 to 29 month group, where it was statistically significant (p=0.037), whereas in the 6-19 year group the situation was reversed. Furthermore, selecting only the atopic children younger than 3 years of age with high IgE levels and clinical symptoms of atopy (wheezing and/or dermatitis) it was possible to demonstrate lower EBV seropositivity compared with the normal IgE controls for each group, even though these differences were not statistically significant. In conclusion, the results of our study suggest that, in our selected population, EBV infection in the first years of life is associated with a lower prevalence of high IgE levels.  相似文献   
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