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51.
Psoriasis is a chronic inflammatory skin disease that can lead to significant physical and psychologic distress for patients. Psoriatic arthritis (PsA), originally thought to be quite a mild disorder, is now recognized as a progressive and destructive arthritis. To date, therapies for both these conditions have been non-specific and unable to maintain long-lasting remission. In addition, many of the current therapies have significant adverse effects, limiting their usefulness. However, elucidation of the pathogenesis of psoriasis and PsA at a molecular level and the development of selective biologic agents have led to an enormous expansion of the armamentarium available to psoriasis patients. Two agents (infliximab and etanercept) selectively block the role of the cytokine tumor necrosis factor (TNF)-alpha and have proved effective in clinical trials in the treatment of both the skin and the joint manifestations of psoriasis. A third anti-TNF alpha agent (adalimumab Humira) is licensed for the treatment of rheumatoid arthritis; however, no studies have been published to date on its use in PsA or psoriasis. It is known that TNF alpha is elevated in both the skin and synovium of psoriatic patients and the effectiveness of its blockade by these two agents in psoriasis and PsA confirms its role in their pathogenesis. Randomized, double-blind, placebo-controlled trials have been performed with both agents in the treatment of psoriasis and PsA; in the case of etanercept these have been to support US FDA approval for use in psoriatic arthropathy. These studies are supported by smaller cohorts in open-label studies and anecdotal reports in the literature. Anti-TNF alpha therapy has proved to have disease-reducing activity in PsA and psoriasis and appears to be well tolerated. These studies have generally featured small numbers of patients and, until a larger cohort of treated patients is available, vigilance must be exercised. A considerable body of post-marketing safety data exists on the use of infliximab in rheumatoid arthritis and Crohn disease and for etanercept in rheumatoid arthritis and PsA. Certain issues, particularly the risk of infection, have emerged as features of the use of these agents. It remains to be seen whether effects seen in other disease entities may be extrapolated to psoriatic patients. More long-term data and experience are needed to define the role of anti-TNF alpha agents in the management of psoriasis and PsA. In particular, more studies are required to elucidate the finer points of co-medication; in some studies both agents have been used with other medications but there have been no formal trials of various possible combinations.  相似文献   
52.
This prospective multisite Phase III clinical trial (Miami, New York, New Jersey) investigated the long-term (one year) effects of a 10-week group cognitive-behavioral stress management/expressive supportive therapy (CBSM+) intervention on disadvantaged minority women living with AIDS. The CBSM+ intervention consisted of 10-weekly group session of stress management, cognitive-behavioral skill training, relaxation techniques and expressive-supportive therapeutic strategies. The primary study outcome was self-reported depression scores as measured by the BDI. The CBSM+ Group intervention significantly decreased depression scores on the BDI for women following the intervention and maintained the decreased level at one-year follow-up.  相似文献   
53.
Melanin pigmentation in mammalian skin and its hormonal regulation   总被引:37,自引:0,他引:37  
Cutaneous melanin pigment plays a critical role in camouflage, mimicry, social communication, and protection against harmful effects of solar radiation. Melanogenesis is under complex regulatory control by multiple agents interacting via pathways activated by receptor-dependent and -independent mechanisms, in hormonal, auto-, para-, or intracrine fashion. Because of the multidirectional nature and heterogeneous character of the melanogenesis modifying agents, its controlling factors are not organized into simple linear sequences, but they interphase instead in a multidimensional network, with extensive functional overlapping with connections arranged both in series and in parallel. The most important positive regulator of melanogenesis is the MC1 receptor with its ligands melanocortins and ACTH, whereas among the negative regulators agouti protein stands out, determining intensity of melanogenesis and also the type of melanin synthesized. Within the context of the skin as a stress organ, melanogenic activity serves as a unique molecular sensor and transducer of noxious signals and as regulator of local homeostasis. In keeping with these multiple roles, melanogenesis is controlled by a highly structured system, active since early embryogenesis and capable of superselective functional regulation that may reach down to the cellular level represented by single melanocytes. Indeed, the significance of melanogenesis extends beyond the mere assignment of a color trait.  相似文献   
54.
Polyamines are important for protein synthesis and tissue growth. In rat salivary glands, the activity of ornithine decarboxylase (ODC), the enzyme catalysing the formation of putrescine, and the content of putrescine, spermidine, spermine and N1-acetylspermidine were assayed after parasympathetic or sympathetic nerve stimulation in the presence of various autonomic receptor blockers. Increases in ODC activity occurred on activation of non-adrenergic and non-cholinergic receptors in response to parasympathetic nerve stimulation and on activation of alpha(alpha 1)- as well as of beta(beta 1)-adrenoceptors in response to sympathetic nerve stimulation. Moreover, in parotid glands, a beta(beta 1)-adrenoceptor-mediated inverse pathway for putrescine formation seemed to exist: from spermidine via N1-acetylspermidine.  相似文献   
55.
Posterior and anterior heights, cross-sectional area and shape were measured for all the intervertebral discs in four spines from elderly human cadavers. Disc height was a minimum at the T4-5 level; thoracic discs were less wedge-shaped than those in the cervical and lumbar regions. Cross-sectional area increased from the cranial to caudal extremity; at the L5-S1 level the nucleus pulposus occupied a high proportion of this area. Cervical discs tended to have an elliptical cross-sectional shape, thoracic discs were more circular and lumbar discs tended to have an elliptical cross-section which was flattened or re-entrant posteriorly. This shape distribution was quantified by defining a shape index which had a maximum value of 1 for a circular cross-section. Orientations of the reinforcing fibres in the outer lamellae of the anterior annulus fibrosus were measured from 27 discs by X-ray diffraction. For these measurements, C3-4, T7-8 and L2-3 were chosen as representative of cervical, thoracic and lumbar discs. The fibre tilt, with respect to the axis of the spine, was significantly less in the cervical discs (at 65 degrees) than in the thoracic and lumbar discs (about 70 degrees). These findings are interpreted in relation to differing functional requirements and possible mechanisms of failure in the cervical, thoracic and lumbar regions of the spine in the light of current knowledge on the biomechanics of the intervertebral disc.  相似文献   
56.
Immunohistology was used for the detection of Legionella pneumophila serogroup I in necropsy tissue. Study of pneumonic lung from the recent Stafford outbreak has shown that this technique has a high sensitivity. A retrospective postmortem examination showed that L pneumophila serogroup 1 was an unusual cause of pneumonia in Oxfordshire during the study period. L pneumophila serogroup 1 can be successfully subgrouped, using a panel of monoclonal antibodies on formalin fixed paraffin embedded sections. Immunohistological methods have a potentially useful role in the diagnosis of Legionellosis at postmortem examination and in the epidemiological investigation of individual cases and outbreaks.  相似文献   
57.
目的: 观察内洋地黄素特异性拮抗剂地高辛抗血清对心肌缺血再灌注(MIR)损伤大鼠心肌组织内洋地黄素水平、钠泵活性、线粒体总钙浓度以及钠泵各亚基基因表达的影响,探讨内洋地黄素在心肌缺血再灌注损伤中的作用及其机制。方法: 将56只雄性SD大鼠随机分成7组,每组8只。假手术对照组(sham):丝线穿过左冠状动脉前降支,但不结扎;缺血再灌注组(MIR):结扎左冠状动脉前降支30 min,再灌注45 min;生理盐水组(NS)、维拉帕米组(Ver)、小剂量、中剂量、大剂量地高辛抗血清组(ADA):于再灌注前5 min经股静脉分别注射生理盐水、维拉帕米5 mg·kg-1、地高辛抗血清8.6 mg·kg-1、 17.3 mg·kg-1、34.5 mg·kg-1,容积均为5 mL·kg-1,5 min内注射完毕,其余同MIR模型组。再灌注结束后,立即取缺血区左室心肌检测心肌匀浆内洋地黄素水平、心肌细胞膜Na+ K+ATP酶和Ca2+Mg2+ATP酶活性、线粒体总钙浓度;分别采用RT-PCR及Western blotting方法和免疫组化方法检测心肌钠泵α1、α2、α3和β1亚基mRNA及蛋白水平基因表达的改变。结果: 心肌缺血再灌注损伤时,心肌组织内洋地黄素水平明显升高,心肌细胞膜钠泵和Ca2+Mg2+ATP酶活性显著下降,线粒体总钙浓度升高,钠泵α1、α2、α3和β1亚基在mRNA及蛋白水平基因表达均明显下降;维拉帕米除具有降低线粒体总钙浓度外,对其它各项指标无明显影响。地高辛抗血清呈剂量依赖性地显著降低心肌组织内洋地黄素水平,恢复细胞膜钠泵和Ca2+Mg2+ATP酶活性,降低线粒体总钙浓度,上调钠泵α1、α2、α3和β1亚基mRNA及蛋白水平的基因表达。结论: 心肌缺血再灌注促进机体内洋地黄素分泌增加,后者通过下调心肌细胞膜上的钠泵α1、α2、α3和β1亚基基因表达抑制钠泵活性,进而抑制Ca2+Mg2+ATP酶活性,导致线粒体内钙超载,介导心肌缺血再灌注损伤。内洋地黄素特异性拮抗剂地高辛抗血清通过阻断内洋地黄素的生物学作用,上调钠泵各亚基的基因表达,发挥其抗心肌缺血再灌注损伤的作用。  相似文献   
58.
Adhesion formation is a major source of postoperative morbidity and mortality. In this study, the ability of a variety of lazaroid formulations [the antioxidant 21-aminosteroid PNU74006F (tirilazad) and the non-steroidal 2-methylaminochroman derivative PNU83,836E] to reduce i.p. adhesion formation in three rabbit models was examined. In initial studies, PNU83836E was administered via Alzet miniosmotic pump to the site of injury. In the sidewall and double uterine horn models, PNU83,836E was administered via Alzet miniosmotic pump for the entire postoperative interval. In the sidewall model, there was a dose- dependent reduction in the area of the sidewall injury that was involved in adhesions. In the double uterine horn model, PNU83,836E was administered via Alzet miniosmotic pump to the area of injury for 1, 2, 3 or 7 days. Administration for as little as 24 h after surgery significantly reduced the extent of adhesion formation and the reduction was increased if it was administered for longer. Further studies were conducted in which various lazaroid formulations were administered as a bolus at the end of surgery. In both the sidewall and double uterine horn models, administration of either PNU83,386E (in citrate buffer) or PNU74006F (in cyclodextrin or lipid emulsion vehicles) at the end of surgery reduced adhesion formation. Administration of a bolus of PNU74006F 10 min prior to initiation of surgery with or without additional treatment at the end of surgery further increased its efficacy in the reduction of adhesion formation. Administration of a minimum of 1.5 mg before and after surgery (3 mg total) was required for maximal efficacy. These studies demonstrate that pre- and postoperative administration of either a steroidal (PNU74006F) or non-steroidal (PNU83,836E) lazaroid intraperitoneally reduced the formation and reformation of postoperative adhesions in three animal models.   相似文献   
59.
冠心病家族史青少年载脂蛋白E、B的基因多态性   总被引:8,自引:2,他引:8  
目的 探讨青少年载脂蛋白E(apolipoprotein E,apoE)、apoB基因多态性对冠心病的遗传易感性。方法 应用聚合酶链反应—限制性片段长度多态性技术,对244名健康汉族大学生(冠心病家族史阳性者109人,阴性者135人)的apoE、apoB XbaI、apoB 3’可变数目串联重复序列(variable number of tandem repeat ,VNTR)基因型进行分析。结果 阳性组的e4、x^ 、VNTR—B(hypervariable element,HVE>38)等位基因频率显著高于阴性组(P<0.05),且与血总胆固醇、低密度脂蛋白—胆固醇、aPoBl00水平升高有显著相关(P<0.05)。结论 apoE的e4、apoB Xba I的x^ 、apoB3’VNTR的VNTR—B可能为冠心病的重要遗传标记。  相似文献   
60.
In the presence of atropine continuous trains of impulses applied to the auriculo-temporal nerve at relatively high frequencies evoked a flow of parotid saliva that amounted to 5-10% of that before administration of the muscarinic blocker. The output of total protein, amylase, sodium and potassium decreased markedly. However, in terms of concentration protein and amylase increased, while sodium decreased and potassium was unchanged. When, in the absence of atropine, the continuous mode of stimulation was replaced by bursts of impulses of high frequencies the amount of saliva decreased. However, the concentration of protein, amylase and potassium increased, while the concentration of sodium decreased. The findings are discussed in relation to a possible peptidergic innervation of the secretory elements.  相似文献   
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