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R Mandeville F Dumas A Amarouch S Sidrac-Ghali M C Walker M Zelechowska I Ajdukovic B Grouix 《Hybridoma》1987,6(5):441-451
This study reports the purification and characterization of a high molecular weight human breast cancer-associated antigen identified by a previously described (1,2) murine monoclonal antibody, BCD-B4. Immunohistochemical analysis indicated that BCD-B4 recognizes an antigen expressed in an altered form on the human breast carcinoma cell line, BT-20, compared to the non-malignant human mammary epithelial cell line, HBL-100. Chemical treatments and enzymatic digestions suggested that the recognized moiety was a protein. The antigenic determinant was resistant to neuraminidase and periodate treatments but was sensitive to trypsin and proteinase K. The antigen was purified by affinity chromatography and its molecular weight, determined by SDS-PAGE analysis under non-reducing conditions, was proven to be 250 Kd. Under reducing conditions, the molecule dissociated into two polypeptides of 125 and 45 Kd, respectively. Both subunits could be isolated from normal HBL-100 and neoplastic BT-20 cellular protein extracts by affinity chromatography. The higher molecular weight subunit showed; however, qualitative and quantitative differences between the two cell lines: it was expressed in greater quantity on BT-20 cells and its molecular weight was 15 Kd higher. Both subunits could also be identified by immunoblots of BT-20 cells. 相似文献
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Despite a high prevalence of chronic muscle pain disorders such as fibromyalgia and regional myofascial pain, there is still limited knowledge about the factors that initiate and perpetuate these pain states. Although there are also likely to be downstream neuropathic changes in the central nervous system and spinal cord that sustain and exacerbate the pain states known as fibromyalgia, the focus of this critical review is on studies that examined the connection between both fibromyalgia and regional myofascial pain and sympathetic function. Specifically, we looked at studies that described Raynaud-like symptoms, cardiovascular dysfunction and altered intramuscular perfusion in chronic muscle pain. Our analysis showed that although the first 2 phenomena were intermittently present, a prominent and consistent feature for regional myofascial pain and to a lesser degree for fibromyalgia was intramuscular hypoperfusion. Several hypotheses can be offered why this hypoperfusion exists, and additional studies comparing and contrasting these theories are needed. This review focuses on one of these theories, namely, agonist-induced beta-adrenergic receptor desensitization as an explanatory model for hypoperfusion. What cannot be done at this time and is needed in the future is to compare and contrast to what degree the regional muscle pain disorder (myofascial) is similar or different from the more generalized disorder (fibromyalgia). 相似文献
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Cough and paradoxical vocal fold motion 总被引:8,自引:0,他引:8
Kenneth W. Altman MD PhD C. Blake Simpson MD Milan R. Amin MD Mona Abaza MD Ron Balkissoon MD Roy R. Casiano MD 《Otolaryngology--head and neck surgery》2002,127(6):501-511
OBJECTIVES: The differential diagnosis and treatment of patients with chronic cough, paradoxical vocal fold motion, and disordered breathing can be a challenge to most practicing otolaryngologists. Tracheobronchial (ie, asthma, bronchitis, and tracheal stenosis), laryngeal (ie, vocal fold paralysis and neoplasms), and rhinologic (ie, allergies and rhinosinusitis) etiologies are commonly diagnosed and treated effectively. However, occasionally one is faced with patients who are refractory to medical treatment and have no obvious rhinologic, laryngeal or pulmonary cause. STUDY DESIGN AND SETTING: We conducted a review of the literature. METHODS: We present a thorough review of the current medical literature exploring the complex neurologic mechanisms involved in the production of cough and the relationship between gastroesophageal reflux disease, vagal neurapathy, and paradoxical vocal fold motion. RESULTS: The diagnosis and successful treatment of chronic cough can be complex. It requires a thorough understanding of the neurologic mechanisms behind cough excitation and suppression. Successful treatment strategies include aggressive management of the patient's reactive airway disease, gastroesophageal reflux disease, and, in select cases, paradoxical vocal fold motion. This may involve a well-coordinated effort among pulmonologists, otolaryngologists, gastroenterologists, and speech pathologists. CONCLUSION: Gastroesophageal reflux disease, vagal neuropathy, and paradoxical vocal fold motion are additional causes of chronic cough and disordered breathing that need to be considered, in the absence of obvious laryngotracheal and/or rhinologic pathology. A high index of suspicion is essential in making the diagnosis and formulating an effective multidisciplinary treatment plan for these patients. 相似文献
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