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Vitiligo and psoriasis are both common skin disorders. However, psoriasis strictly confined to pre-existing vitiligo areas is rare and suggests a causal relationship. We report here on two patients with a strict anatomical colocalization of vitiligo and psoriasis. The histopathological examinations showed typical changes for both diseases together with a dense infiltrate of CD4+ and CD8+ T cells. By immunohistochemistry, intracytoplasmatic granzyme B and tumour necrosis factor alpha (TNF-alpha) were detected within the T-cell population, suggesting the functional activity of these cells and the creation of a local T helper 1 (Th1)-cytokine milieu. Additionally, in one patient we could identify anti-melanocytic T cells by tetramer staining and enzyme-linked immunospot (ELISPOT) analysis. These skin-infiltrating lymphocytes might trigger, by the local production of Th-1 cytokines such as TNF-alpha and interferon-gamma (IFN-gamma), the eruption of psoriatic plaques in patients with a genetic predisposition for psoriasis.  相似文献   
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Objective. The safety and efficacy of intrathecal (IT) ziconotide was studied in a randomized, double‐blind, placebo‐controlled trial. Materials and Methods. Patients (169 ziconotide, 86 placebo) with severe chronic nonmalignant pain unresponsive to conventional therapy and a visual analog scale of pain intensity (VASPI score) ≥ 50 mm were treated over a 6‐day period in an inpatient hospital setting. Initial starting dose was 0.4 µg/hour and was titrated to analgesia or intolerance (maximum dose 7.0 µg/hour). The starting and maximum doses were reduced to 0.1 µg/hour and 2.4 µg/hour, respectively, due to adverse events (AEs). Results. The mean percent reduction in VASPI score from baseline was 31.2% and 6.0% for ziconotide‐ and placebo‐treated patients, respectively (p ≤ 0.001). During the initial titration phase, a significantly greater percentage of patients in the ziconotide group compared to the placebo group reported AEs, including abnormal gait, amblyopia, dizziness, nausea, nystagmus, pain, urinary retention, and vomiting. Conclusion. Ziconotide provided significant analgesia in patients for whom conventional therapy failed. However, there was a considerable incidence of ziconotide‐associated AEs due to the rapid titration and high doses administered.  相似文献   
4.
Sublethal doses (0.00, 0.25, 0.50 and 1.00 mg/kg b.w./day) of vomitoxin (deoxynivalenol; DON) were studied for their effects on humoral and cellular immunity and serum proteins of inbred, male Swiss Webster mice in a series of 4 separate experiments. Vomitoxin was added to basal diet (less than the detection limit, i.e., less than 0.05 micrograms of vomitoxin per g of feed) and administered to mice for 5 weeks beginning at 21 days of age. Mice in experiment 2 were fed the basal diet for 40 days in addition to the 5-week treatment with vomitoxin. The 1.00 mg/kg dose of vomitoxin resulted in a statistically significant reduction in the serum levels of alpha 1 and alpha 2-globulins, an increase in total serum albumin, and a reduction in feed consumption and body weight gain compared to the control group. The 0.50 mg/kg dose of vomitoxin resulted in significantly reduced serum levels of alpha 2- and beta-globulins while a significant reduction of feed consumption was evident only during Week 4. Similarly, body weight gain in this group of mice was significantly reduced during Week 2 but increased to normal levels during Week 3 and remained parallel to the control for Week 4 and 5. Both levels (0.50 and 1.00 mg/kg) of vomitoxin resulted in a reduced, dose-related, time-to-death interval following a challenge with L. monocytogenes and increased proliferative capacity of splenic lymphocyte cultures stimulated with the phytohemagglutinin P (PHA-P) mitogen compared to the control group of mice. The 0.25 mg/kg dose of vomitoxin did not have any significant effects on the parameters studied. A reasonable estimation of a 'no effect' level for immunologic effects in mice based on these and previous immunological studies would seem to be between 0.25 and 0.50 mg/kg b.w./day.  相似文献   
5.
A study was conducted to evaluate the efficacy of family history factors as screening criteria for childhood hypercholesterolemia. When they were seen for routine care at one of eight office practices, 1005 prepubertal children underwent random serum cholesterol determinations. Parental and grandparental histories of cardiovascular risk factors and atherosclerotic complications prior to 55 years of age were also obtained. Of the initial group, 274 children had total cholesterol levels greater than or equal to 175 mg/dL, and 175 of these children returned for retesting after an overnight fast. A total of 88 children were found to have low-density lipoprotein-cholesterol (LDL-C) values greater than or equal to 90th percentile for age and sex. Maternal and paternal histories of hypercholesterolemia were significantly associated with elevated LDL-C (odds ratio = 7.3 and 2.9, respectively), but had extremely low sensitivities (0.09, 0.15) despite modest positive predictive values (0.42, 0.22). Grandparental histories of sudden death, peripheral vascular disease, and gout were associated with elevated LDL-C, but sensitivities and positive predictive values for all of these factors were less than 0.22. Family history factors most commonly recommended as criteria for cholesterol screening in children did not identify half of all the children with elevated LDL-C and did not selectively identify the most severely affected children. Adding information concerning the presence of childhood obesity did not result in appreciable improvement in LDL-C detection beyond that achieved by family history factors alone. It was concluded that if thorough identification of young children with elevated LDL-C is desired, inclusive population screening rather than a family history-based strategy would be the most effective approach.  相似文献   
6.
In defining the linear extent of a malignant tumor in a long bone, radiographs, computerized tomography, and scintigraphy are routinely employed, especially when non-ablative surgery is being considered. The drawbacks of these modalities in defining the true intracompartmental extent of disease within a bone can largely be overcome with the use of magnetic resonance imaging. We did a prospective analysis of magnetic resonance imaging in sixteen consecutive patients with a primary malignant tumor of a long bone, and it showed that this modality has clinical promise of being more precise than the other modalities in defining the true proximal and distal extent of a tumor in a long bone. Coronal images permit easier planning of surgical techniques for salvage of a limb using an allograft than do a multiplicity of transverse images.  相似文献   
7.
OBJECTIVE: The purpose of this study was to determine whether social skills training can improve the social interaction skills of adolescents with craniofacial conditions (CFCs) in a natural environment (school lunchroom). DESIGN: This study used a pre-post between-group comparison design. Differences between treatment and control subjects were analyzed via a repeated measures analysis of variance. SETTING: The observations were conducted in the respective school lunch-rooms of the adolescents. Social skills groups were conducted in an outpatient clinic setting. MAIN OUTCOME MEASURES: Structured data based on 45 minutes of observation was coded for type, frequency, and duration of social contact. Specific measures included subject initiations and responses, peer initiations and responses, conversation events, total positive communication, and frequency of nondirected comments. RESULTS: Both target and peer-controlled total communication improved across time with adolescents receiving social skills intervention showing significantly more improvement than those adolescents not receiving direct social skills interventions. Adolescents receiving treatment participated in significantly more target initiated conversations lasting at least three interchanges and showed a trend toward a greater frequency of target initiations and positive responses to peer initiations. Peers were more likely to respond to treatment subject initiations after intervention. Fewer treatment subjects used nondirected communication, whereas control subjects continued to use nondirected communication at a slightly increased frequency. CONCLUSIONS: This study provides preliminary evidence that social skills training can increase the frequency of positive social interactions with peers for adolescents with CFCs.  相似文献   
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Monoclonal antibody (MAb) WM-25 differentiates by in vitro growth inhibition Mycoplasma capricolum subsp. capripneumoniae (Mycoplasma strain F38), which causes contagious carpine pleuropneumonia, from other Mycoplasma spp. (F. R. Rurangirwa, T. C. McGuire, A. J. Musoke, and A. Kibor, Infect. Immun. 55:3219-3220, 1987). The antigen identified by MAb WM-25 was isolated from solubilized Mycoplasma strain F38 organisms by MAb WM-25 affinity chromatography and was stained with Schiff's reagent, but not with Coomassie blue, after separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Treatment of purified F38 polysaccharide with periodate abolished binding with MAb WM-25, and MAb WM-25 binding was blocked with laminarin, a complex oligosaccharide with beta(1-->3) sugar linkages. Purified F38 polysaccharide blocked both growth inhibition and agglutination of live F38 organisms caused by MAb WM-25 and rabbit antiserum to F38 organisms. The results in this paper demonstrate that MAb WM-25 binds a periodate-sensitive epitope on the F38 polysaccharide which is also exposed on the surface of Mycoplasma strain F38. Because MAb WM-25 also causes in vitro growth inhibition of F38, the reactive polysaccharide epitope may induce protective immune responses.  相似文献   
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