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91.
Oral lichenoid drug eruptions   总被引:1,自引:0,他引:1  
OBJECTIVES: To identify, from amongst drugs reported as causing lichenoid drug eruptions, those affecting the oral mucous membranes and to review the clinical, histo-logical and immunological features of such oral lichenoid drug eruptions in comparison to oral lichen planus, amalgam contact lesions and lichen planus-like eruption in graft-versus-host disease (GVHD).
DATA SOURCES: Ovid® Medline data searches on CD-Rom were carried out for the years 1966–1996 to identify reports of oral lichenoid drug eruptions and their clinical, histological and immunological featureS. Articles retrieved were examined for further appropriate references in the period 1940–1996.
DATA EXTRACTION AND SYNTHESIS: Each paper was critically examined for evidence of a clinically verifiable lichenoid drug eruption affecting the oral mucous membranes and the effects of subsequent drug withdrawal. Available clinical, histological and immunological features were recorded. The papers examined were too diverse in nature to permit a structured criticism. The extracted data have been tabulated where appropriate.
CONCLUSIONS: The reports of oral lichenoid drug eruptions are considerably fewer than those of cutaneous eruptions and fewer drugs have been reported as causing oral rather than cutaneous lichenoid eruptionS. Histology and immunology cannot be used reliably to differentiate lichenoid drug eruptions from idiopathic lichen planus, amalgam contact lesions and lichen planus-like eruption in GVHD. Lichenoid drug eruptions may also show some histological characteristics of oral discoid lupus erythematosuS. An accepted protocol agreed by a number of international centres would permit the gathering of substantial information on LDE and could lead to a greater understanding of the mechanisms involved.  相似文献   
92.
93.
The immunophenotypes of lymphoblasts from children with newly diagnosed T-cell acute lymphoid leukemia (T-ALL, n = 101) or T-cell non-Hodgkin lymphoma (T-NHL, n = 31) were analyzed to correlate stage of thymocyte differentiation with clinical features and outcome. The 67 boys and 34 girls with T-ALL were 1 month to 18 years old (median, 8 years) with leukocyte counts ranging from 2 to 810 x 10(9)/L (median, 55 x 10(9)/L). Eighteen of these patients were black, and 70 had a mediastinal mass. Twenty-six boys and five girls with a median age of 9 years (range, 1 to 20 years) had T-NHL. Seven of these patients were black, and 24 had a mediastinal mass. The distributions of thymocyte developmental stages (early [CD7+], intermediate [CD1+ and/or CD4+ and/or CD8+], and mature [CD3+]) in cases of T-ALL and T-NHL were significantly different: 34%, 43%, and 23% v 6%, 62%, and 32% (P = .02). A comparison of the patients' clinical features according to the maturational stage of thymocytes failed to disclose significant differences in the majority of characteristics studied. However, patients with mature-stage T-NHL, with or without the addition of subjects with mature-stage T-ALL, were less likely to have a mediastinal mass (P = .02 for both comparisons). Those with intermediate-stage T-cell malignancy (T-ALL and T-NHL combined) were the subgroup most likely to have a mediastinal mass (P = .01). Response to remission induction therapy was significantly worse in the T-ALL subgroup with an early-stage phenotype: a failure rate of 21% v 0% and 6% for the two more differentiated phenotypic subgroups (P = .007). Event-free survival was not affected by thymocyte maturational stage in cases of either T-ALL or T-NHL. Despite evidence of clinical heterogeneity among the maturational stages of T-cell malignancies in children, these developmental subdivisions do not appear to be critical determinants of outcome once remission is achieved. We conclude that such phenotypes need not be included in the stratification plans for clinical trials using common induction treatment.  相似文献   
94.
Heritable somatic methylation and inactivation of MSH2 in families with Lynch syndrome due to deletion of the 3' exons of TACSTD1
Ligtenberg et al. (2009)
Nature Genetics 41: 112–117  相似文献   
95.
96.
2002年5月1日颁布实施的《中华人民共和国职业病防治法》是规范职业卫生技术服务行为的法律依据。这是职业卫生技术服务工作走上规范化、标准化、法制化的根本保障,是职业卫生技术服务机构参与市场竞争、提高服务质量、促进自身发展的必由之路,也是企业自主选择职业卫生技术服务机构、提高职业危害防治水平、促进经济发展的关键所在。4年多来,我市各级各类职业卫生技术服务机构的发展极不平衡,仪器设备配备水平、人员能力素质与我省同类地区相比也有较大差距。为了解我市职业卫生技术服务机构现状,我们进行了此项调查。  相似文献   
97.
目的:观察开道散合扶正和胃合剂治疗上消化道癌性狭窄的临床疗效。方法:对40例患者采用口服开道散、扶正和胃合剂联合胃镜下癌灶内注射5-氟脲嘧啶注射液及鸦胆子乳剂方法治疗上消化道癌性狭窄。结果:治疗后无瘤灶消失病例,34例患者肿瘤缩小达50%以上,完全缓解0例,部分缓解34例,稳定4例,进展2例,有效率为85.0%。治疗后患者吞咽困难有了较明显的改善,显效7例,有效31例,无效2例,总有效率95.0%。治疗后所有患者的卡氏评分均有所升高,与治疗前比较,差异有显著性意义(P〈0.05),提示治疗后患者的生活质量有所改善。结论:开道散合扶正和胃合剂治疗上消化道癌性狭窄疗效满意,能使实体瘤缩小、吞咽困难改善、生活质量提高。  相似文献   
98.

Background and purpose:

α- and β-amyrin are pentacyclic triterpenes found in plants and are known to exhibit pronounced anti-inflammatory effects. Here, we evaluated the effects of a 1:1 mixture of α- and β-amyrin (α,β-amyrin) on an experimental model of colitis in mice.

Experimental approach:

Colitis was induced in Swiss male mice by trinitrobenzene sulphonic acid (TNBS) and followed up to 72 h; animals were treated systemically with α,β-amyrin, dexamethasone or vehicle. Macro- and microscopic damage, myeloperoxidase activity and cytokine levels were assessed in colons. Histological sections were immunostained for cyclooxygenase-2 (COX-2), vascular endothelial growth factor, phospho-p65 nuclear factor-κB (NF-κB) and phospho-cyclic AMP response element-binding protein (CREB)

Key results:

TNBS-induced colitis was associated with tissue damage, neutrophil infiltration and time-dependent increase of inflammatory mediators. Treatment with α,β-amyrin (3 mg·kg−1, i.p.) or dexamethasone (1 mg·kg−1, s.c.) consistently improved tissue damage scores and abolished polymorphonuclear cell infiltration. α,β-Amyrin, like dexamethasone, significantly diminished interleukin (IL)-1β levels and partially restored IL-10 levels in colon tissues 72 h after colitis induction, but only α,β-amyrin reduced vascular endothelial growth factor expression by immunohistochemistry. The colonic expression of COX-2 at 24 h and that of phospho-NF-κB and phospho-CREB (peaking at 6 h) after colitis induction were consistently inhibited by both α,β-amyrin and dexamethasone.

Conclusions and implications:

Systemic administration of α,β-amyrin exerted a marked and rapid inhibition of TNBS-induced colitis, related to the local suppression of inflammatory cytokines and COX-2 levels, possibly via inhibition of NF-κB and CREB-signalling pathways. Taken together, our data suggest a potential use of α,β-amyrin to control inflammatory responses in bowel disease.  相似文献   
99.

Background and purpose:

This study investigates the role of α2-adrenoceptor subtypes, α2A, α2B and α2C, on catecholamine synthesis and catabolism in the central nervous system of mice.

Experimental approach:

Activities of the main catecholamine synthetic and catabolic enzymes were determined in whole brains obtained from α2A-, α2B- and α2C-adrenoceptor knockout (KO) and C56Bl\7 wild-type (WT) mice.

Key results:

Although no significant differences were found in tyrosine hydroxylase activity and expression, brain tissue levels of 3,4-dihydroxyphenylalanine were threefold higher in α2A- and α2C-adrenoceptor KO mice. Brain tissue levels of dopamine and noradrenaline were significantly higher in α2A and α2CKOs compared with WT [WT: 2.8 ± 0.5, 1.1 ± 0.1; α2AKO: 6.9 ± 0.7, 1.9 ± 0.1; α2BKO: 2.3 ± 0.2, 1.0 ± 0.1; α2CKO: 4.6 ± 0.8, 1.5 ± 0.2 nmol·(g tissue)−1, for dopamine and noradrenaline respectively]. Aromatic L-amino acid decarboxylase activity was significantly higher in α2A and α2CKO [WT: 40 ± 1; α2A: 77 ± 2; α2B: 40 ± 1; α2C: 50 ± 1, maximum velocity (Vmax) in nmol·(mg protein)−1·h−1], but no significant differences were found in dopamine β-hydroxylase. Of the catabolic enzymes, catechol-O-methyltransferase enzyme activity was significantly higher in all three α2KO mice [WT: 2.0 ± 0.0; α2A: 2.4 ± 0.1; α2B: 2.2 ± 0.0; α2C: 2.2 ± 0.0 nmol·(mg protein)−1·h−1], but no significant differences were found in monoamine oxidase activity between all α2KOs and WT mice.

Conclusions and implications:

In mouse brain, deletion of α2A- or α2C-adrenoceptors increased cerebral aromatic L-amino acid decarboxylase activity and catecholamine tissue levels. Deletion of any α2-adrenoceptor subtypes resulted in increased activity of catechol-O-methyltransferase. Higher 3,4-dihydroxyphenylalanine tissue levels in α2A and α2CKO mice could be explained by increased 3,4-dihydroxyphenylalanine transport.  相似文献   
100.
 目的 研究Ewing’s肉瘤细胞系 (RM 82 )X 射线外照射后肿瘤坏死因子 (TNF α)和转化生长因子 (TGF β)mRNA表达水平的变化 ,探讨X 射线诱导内源性TNF α和TGF β产生的可能性及意义。 方法 应用实时荧光RT PCR ,检测接受不同剂量X 线照射 (2Gy ,5Gy ,10Gy ,2 0Gy ,30Gy ,4 0Gy)和受照后不同时间 (1h ,3h ,6h ,12h ,2 4h ,4 8h ,72h)。TNF α和TGF βmRNA表达水平的变化。 结果 RM 82细胞TNF αmRNA表达水平较外照射前显著升高。一方面受照后TNF αmRNA表达逐渐升高 ,照射剂量达 4 0Gy时TNF αmRNA表达水平达高峰 ,为正常对照组的 10 8倍 ;另一方面 ,照射后 3h后TNF αmRNA表达逐渐升高 ,6h达高峰 ,为正常对照组的 18倍。相反 ,TGF βmRNA表达水平X 射线照射前后无显著变化。结论 Ewing’s肉瘤细胞系 (RM 82 )接受X 线照射后TNF αmRNA表达明显升高 ,且呈现时间、剂量依赖性。放射治疗可诱导Ewing’s肉瘤细胞系 (RM 82...  相似文献   
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