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131.
Radiation-induced breast angiosarcoma, or secondary angiosarcoma (SAS), is a rare entity with a high risk of metastatic recurrence. Herein, we describe the use of intraoperative fluorescence-based skin angiography to guide surgical resection following a novel immunotherapy-based regimen for SAS resulting in a complete pathological response.  相似文献   
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133.
Nerve growth factor (NGF) regulates the survival and development of specific populations of neurones and is involved in wound healing. A further area of study relating to the role of neurotrophins in the mature animal has concerned the possibility that NGF may be a pivotal mediator of inflammation and pain. It has previously been shown that injection of intradermal NGF can result in a neutrophil-dependent hyperalgesia in the rat. The purpose of the present study was to examine the pathological consequence of NGF injected intradermally into mature rat skin and to examine further the role of neutrophils. Standard histopathology techniques (H & E) were employed to determine inflammatory cell counts. Circulating neutrophils were depleted using an anti-rat neutrophil antiserum and results were compared to treatment with vehicle controls. Saline-pretreated rats exhibited normal circulating neutrophil numbers and the dorsal skin showed a significant increase of neutrophil and macrophages at 3 and 5 h and lymphocytes at 5 h after NGF treatment. By comparison, skin sites from neutrophil-depleted rats did not demonstrate a significant increase in neutrophil and macrophage accumulation after NGF administration. All NGF-treated sites, independent of pretreatment, demonstrated abnormal muscle fibre morphology and proliferation of the muscle sarcolemmal nuclei after NGF injection, indicative of tissue injury. In addition, oedema and some fibroplasia were also noted. Furthermore, fibrin production was increased at 3 and 5 h after NGF administration. It is suggested that NGF has a damaging effect on rat muscle which is independent of accumulating neutrophil and other inflammatory cells. In conclusion, the findings indicate a link between NGF-induced neutrophil and macrophage accumulation, as the increase in dermal macrophages was not observed in neutrophil-depleted rats. The results also suggest that NGF can have a profound effect on rat muscle and that this effect may be related to muscle regeneration.  相似文献   
134.
The pathogenesis of human asthma and the development of key features of pulmonary allergy in mouse models has been critically linked to IL-13. Analyses of the receptor components employed by IL-13 have shown that delivery of this cytokine to the airways of naive IL-4Ralpha gene targeted (IL-4Ralpha(-/-)) mice fails to induce disease, suggesting that this membrane protein is critical for transducing IL-13-mediated responses. The current study demonstrates that, in contrast to naive mice, T helper 2 bias, airways hyperreactivity (AHR) and tissue eosinophilia develop in Ovalbumin-sensitized IL-4Ralpha(-/-) mice and that these responses can be inhibited by the IL-13 antagonist sIL-13Ralpha2Fc. Therefore, antigen stimulation induces an IL-13-regulated response that is independent of IL-4Ralpha. To determine the role of IL-5 and eosinophils in the development of disease in antigen-exposed IL-4Ralpha(-/-) mice, pulmonary allergy was examined in mice deficient in both factors. IL-4Ralpha/IL-5(-/-) mice were significantly defective in their ability to produce IL-13 and failed to develop AHR, suggesting that IL-5 indirectly regulates AHR in allergic IL-4Ralpha(-/-) mice by an IL-13-dependent mechanism. Collectively, these results demonstrate that IL-13-dependent processes regulating the development of AHR and T helper bias persist in the in the lungs of allergic IL-4Ralpha(-/-) mice.  相似文献   
135.
Identification of quinolinic acid in rat and human brain tissue   总被引:20,自引:0,他引:20  
An analytical technique for the determination of the excitotoxic compound quinolinic acid (2,3-pyridine dicarboxylic acid) in brain tissue has been developed. Following sample prepurification by ion exchange and high pressure liquid chromatography, quinolinic acid is converted to the dihexafluoroisopropyl ester and the derivative is analyzed by mass fragmentography. Using the present technique quinolinic acid has been identified in both rat and human brain tissue.  相似文献   
136.
Conventional psychometric measures uniformly yield zero or near zero scores (i.e., "bottom-out") as patients with Alzheimer's disease (AD) progress to the more severe stages of the illness. Consequently, there are no psychometric measures which objectively assess the mental abilities of AD patients with very severe cognitive impairment. We explored the hypothesis that mental function in AD patients with very severe cognitive impairment can be effectively assessed using test measures developed to assess the earliest stage of cognitive development as proposed by Piaget. We also investigated the relationship between decline on these experimental cognitive measures and progressive functional disability in patients with severe cognitive impairment. The results indicate that modified instruments derived from measures developed to assess Piaget's sensorimotor stage of cognitive development provide useful information about the cognitive abilities of very severely impaired AD patients. These modified instruments provide a measure of cognition in these extremely impaired patients that has acceptable validity and demonstrable reliability.  相似文献   
137.
Unacceptable side effects involved in topical steroid usage for uveitis have prompted the search for alternative antiinflammatory drugs for the treatment of ocular inflammation. Cyclooxygenase inhibitors have been widely used for systemic inflammatory conditions over the last two decades and are therefore natural candidates to be studied for uveitis therapy. Previous studies of cyclooxygenase inhibitors in uveitis models yielded inconclusive and sometimes contradicting results. The authors compared the clinical effect of topical dexamethasone, diclofenac and placebo in an immunogenic uveitis model produced in ovalbumin immunized NZW rabbits challenged with ovalbumin in the vitreous. Nine clinical parameters of inflammation were compared employing a double blind placebo controlled protocol. Three groups of 16 eyes each, were assigned for each preparation and were followed for nine days with biomicroscopic examinations. Diclofenac was superior or equal to dexamethasone for iris hyperemia (p=0.059) and conjunctival injection (p=0.02), equal for corneal haziness and AC fibrin, yet inferior for corneal endothelial debris, iris fibrin and AC cells and flare (p<0.05). Placebo was inferior (p<0.05) to the other groups for the above mentioned parameters excluding fibrin precipitation on the iris that was greater in diclofenac treated eyes. While some clinical criteria of inflammation responded better to steroids than to diclofenac, the results of this study show that others responded better or equal to diclofenac. The authors hypothesize that although diclofenac reduces prostaglandin levels it may induce high levels of leukotrienes that maintain cellular exudation.  相似文献   
138.
Objective To detect new mutations among 29 glucose-6-phosphate dehydrogenase (G6PD) deficient individuals from Yunnan province. Methods The nitroblue tetrazolium (NBT) method was used to screen G6PD deficient individuals. Mutation was identified by single strand conformation polymorphism (SSCP), amplification created restriction site (ACRS), amplification refractory mutation system (ARMS) and DNA sequencing. Results Among 29 cases, 18 cases of G1388A, 1 case of C1004A, and 1 case of G1381A were identified. Nine cases remained to be defined. The G1381A mutation is a novel mis-sense mutation, with a substitution of threonine for alanine (A461T). The resultant G6PD had reduced enzymatic activity. In addition, G1381A caused a restriction site of Stu I to disappear, providing a rapid method for the detection of this mutation. Conclusion A novel mis-sense mutation G1381A was found. This mutation results in a substitution of threonine for alanine, producing enzyme with reduced activity. The loss of the Stu I restriction site offers a rapid method for the detection of this mutation.  相似文献   
139.
Aneurysm of sinus of Valsalva dissecting into interventricular septum is a rare entity. We report one such case who was incidentally diagnosed by echocardiography to have this abnormality during evaluation of a clinically suspected isolated aortic regurgitation.KEY WORDS: Aneurysm – dissecting – sinus of Valsalva, Echocardiography  相似文献   
140.
Background: Thymusderived lymphocytes play a critical role in the development of herpes simplex keratitis (HSK). T-cell subsets defined by their expression of various T-cell receptor (TCR) Vß segments were studied following corneal HSV-1 infection (p.i.). Methods: Conjunctiva, corneal limbus and corneal stroma of two inbred BALB/c congenic mouse strains which differ only in the gene products closely linked to the Igh-1 locus on chromosome 12 were analyzed. Results: While C.B-17 mice (Igh-1b) were resistant to HSK, C.AL-20 mice (Igh-1d) clinically developed severe necrotizing keratitis by day 11 p.i. The corneal stroma of C.B-17 mice remained clear, while it was increasingly infiltrated by mononuclear cells and neutrophils in C.AL-20 mice by day 11 p.i. In C.B-17 mice, Thy1.2+ cells were found in the conjunctiva between days 2 to 4 p.i., and subsequently decreased. Only a few Thyl.2+ cells were found in the limbus, and no such cells were found in the stroma. In contrast, in C.AL-20 mice the numbers of Thyl.2+ cells (activated CD4+, Vß8+ T cells) profoundly increased in the conjunctiva by day 4 p.i. These cells infiltrated the limbus between days 7 and 11 p.i. and eventually entered the stromal tissue by day 11 p.i. Conclusions: Our data suggest that the HSV-1-induced corneal tissue destruction is mediated by mononuclear cells and neutrophils and that these cells are probably attracted into the cornea by cytokines elaborated by activated CD4+, Vß8+ T cells.Presented as a paper at the ECORA Meeting, 4–7 October 1993, Bonn  相似文献   
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