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1.
Exhaled breath condensate (EBC) provides a noninvasive means of sampling the lower respiratory tract. Collection of EBC might be useful in the assessment of airway oxidative stress in smokers. The aim of this study was to determine 8-isoprostane and hydrogen peroxide levels in EBC, and, in addition, to investigate the reproducibility of these measurements. EBC samples were collected from 12 healthy male smokers at three time points within 1 week. 8-isoprostane and H2O2 were measured in nonconcentrated EBC using immunochemical and colorimetric assays, respectively. 8-isoprostane and H2O2 were detected in only 36 and 47% of all EBC samples, respectively. It was not possible to calculate the within-subject variation in a reliable manner since only three of the 12 smokers exhibited detectable 8-isoprostane concentrations on all three occasions (mean 4.6 pg x mL(-1); range 3.9-7.7 pg x mL(-1)), whereas H2O2 could not be detected on all three occasions in any of the smokers. Spiking experiments revealed a recovery of 83.5-109.5% for 8-isoprostane and 69.9-129.0%, for H2O2 in fresh EBC samples. It was concluded that levels of 8-isoprostane and hydrogen peroxide cannot be reproducibly assessed in exhaled breath condensate from healthy smokers because of their low concentration and/or the lack of sensitivity of the available assays.  相似文献   
2.
Synkinesias secondary to nerve lesions and aberrant re-innervation are well-known phenomena especially after lesions of the facial nerve. Synkinesias can successfully be treated with botulinum toxin A (BTx A). Synkinesias of the cremaster muscle have not been described or treated to date. We present the case of a 62-year-old man who developed synkinesias of both cremaster muscles after extensive laparatomy for esophageal cancer. Treatment of synkinesias with various oral medications had been unsuccessful. Electromyography-guided injections of BTx A in both cremaster muscles (15 MU on the right and 10 on the left) led to significant symptom relief for an average of 8 weeks. We present the case including pre- and posttreatment video clips.  相似文献   
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Polyarteritis nodosa (PAN) presents mostly as a systemic disease with poor prognosis, rarely in an isolated form with a usually favorable outcome. Both forms may affect the male reproductive system and both forms have been associated with malignancies. We describe for the first time the occurrence of isolated PAN in the reproductive system combined with a mixed germ cell tumor of the testis in a 21-year-old man presenting with symptoms of chronic epididymitis. Two years after surgery he is without evidence of recurrence of either the tumor or PAN.  相似文献   
7.
PROBLEM: The choriocarcinoma cell line Jeg3 suppresses immunity in vitro by secretion of soluble factors like leukemia inhibitory factor suppressing leukocyte activation. The cells lack expression of classical human leukocyte antigen (HLA)-A and -B alleles but express some HLA-C, and non-classical HLA-G and -E. Upon binding to killing inhibitory receptor on natural killer (NK) cells, HLA-G prevents activation of cytolytic activity. We investigated whether Jeg3 cells are capable of immune stimulation after complementation with classical HLA and T cell costimulatory signal CD80. METHOD OF STUDY: Jeg3 cells were transduced to express HLA-A*0201 and/or CD80. Parental Jeg3 or transfectants Jeg3-A2, Jeg3-CD80 or Jeg3-CD80-A2 were used to stimulate allogeneic resting and activated peripheral blood lymphocytes (PBL). The different cell lines were loaded with a HLA-A2-restricted Epstein-Barr virus (EBV) recall antigen peptide epitope and antigen presenting ability was examined. T cell lines specific for Jeg3 and transfectants were generated from HLA-A2 matched and nonmatched donors and compared for expansion, phenotypes and cytolytic activity. RESULTS: While all Jeg3 cell lines induced only marginal proliferation of resting T cells, phytohemagglutinin (PHA)-activated T cells were stimulated by CD80 or CD80-A2 expressing Jeg3. Only the transfectant Jeg3-CD80-A2 was capable of specific T cell stimulation by EBV recall antigen presentation. T cell lines of HLA-A2 non-matched donors stimulated with the Jeg3 transfectants showed significant expansion only when HLA-A2 and the costimulus CD80 were present. T cells from HLA-A2 positive donors did not expand significantly or differentially. No NK cells grew under any condition. In Jeg3-CD80-A2 stimulated T cells lines CD8+ cells expanded preferentially. These T cells exerted cytolytic activity toward all Jeg3 cell lines. CONCLUSION: Our data suggest that, in spite of immunosuppressive mechanisms, proliferative and cytolytic T cell responses are induced by Jeg3 cells when classical HLA- and/or costimulatory signals are present on the cells.  相似文献   
8.
The general characteristics of these telemetrically recorded neurons of dorsal raphe, such as firing rate under nembutal anesthesia, reaction to illumination changes or acoustic stimuli were comparable to those in the literature. The firing rate of the dorsal raphe neurons increased during defensive encounters (+51%±29% S.D.; p<0.005) and defensive fights (+113%±91% S.D.; p<0.02) as compared to the neuronal activity of the undisturbed resting animal. The fearful interaction of the animal with the experimenter led to the strongest increase in the firing rate (+187%±114% S.D.; p<0.002) in all animals tested. The offensive animal showed decreased neuronal activity during offensive encounters (?21%±13% S.D.; p<0.02) and offensive fights (?42%±17%S.D.; p<0.05) as compared with the neuronal activity of the undisturbed resting animal. These findings indicate the crucial importance of the animals appraisal of the situational contex for the activity of dorsal raphe neurons.  相似文献   
9.
目的:探讨视网膜母细胞瘤病理标本的不同取材方法对脉络膜浸润检出率的影响,寻求理想的常规取材方法。方法:复查297只原发摘除的视网膜母细胞瘤眼球的病理切片,比较五平面取材法(151只眼)和单平面取材法(146只眼)对脉络膜浸润的检出率。结果:五平面取材法对脉络膜浸润的检出率(31%)明显高于单平面取材法(17%),且主要是对玻璃膜在肿瘤细胞影响下发生变化的检出率高。脉络浸润的各期都主要分布在五平面取材法的各平面上。结论:五平面取材法能提供判断视网膜母细胞瘤患者预后的较大量病理信息,在日常医疗工作中从人力、物力、财力上能够承受,可作为常规取材方法应用于临床。连续切片取材只作为在特殊情况下对五平面取材法的补充。单平面取材法有可能丢失一些重要的病理信息而应由五平面取材法代替。  相似文献   
10.
In order to investigate the role of the ferric uptake regulator Fur in the porcine lung pathogen Actinobacillus pleuropneumoniae, we constructed an isogenic in-frame deletion mutant, A. pleuropneumoniae Deltafur. This mutant showed constitutive expression of transferrin-binding proteins, growth deficiencies in vitro, and reduced virulence in an aerosol infection model.  相似文献   
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