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991.
992.
Therapeutic application of broadly reactive anti-T cell antibodies can lead not only to potent immunosuppression but also to profound and long-lived T cell depletion. We reasoned that a strategy that almost exclusively targets activated cytopathic donor reactive T cells and spares immunoregulatory networks might prove to be an exceptionally potent and highly selective means of producing long-term engraftment and tolerance. Herein we show that the combined administration of rapamycin and agonist IL-2- and antagonist IL-15-related cytolytic fusion proteins provides for long-term engraftment/tolerance in exceptionally stringent allotransplant models by (1) limiting the early expansion of activated T cells, (2) preserving and even exaggerating their subsequent apoptotic clearance, and (3) further amplifying the depletion of these activated T cells by antibody-dependent mechanisms, while (4) preserving CD4+CD25+ T cell-dependent immunoregulatory networks.  相似文献   
993.
A case of botryoid-type embryonal rhabdomyosarcoma of the renal pelvis in a 49-year-old woman is reported. The tumor led to hydronephrosis. The surgical resection specimen disclosed a translucent, polypoid mass attached to the wall of the renal pelvis by thin stalk. Light-microscopic examination revealed a large exophytic polypoid tumor with intact surface epithelium, which was negative for dysplasia or carcinoma in situ. There was a condensation of epithelioid to spindle cells underneath the basement membrane, forming a cambium layer. The core of the lesion contained interspersed epithelioid to spindle cells with myxoid change and edema. Cells of the cambium layer as well as interspersed cells in the core exhibited marked cytologic atypia with mitotic figures. Immunohistochemical stains for cytokeratin, S-100 and myoglobin were negative, stains for desmin and actin were positive. Although botryoid-type embryonal rhabdomyosarcomas have been reported to occur at various sites in the genital tract and lower urinary tract, to our knowledge, this is the first reported case of the tumor within the renal pelvis. Also, the occurrence of these tumors in adults is quite rare.  相似文献   
994.
BACKGROUND: The aetiology and factors leading to the progression of laryngeal cancer are still unclear. Although human papillomavirus (HPV) has been suggested to play a role, reports concerning the effect of HPV infection on tumour development are controversial. Recently, transfusion transmitted virus (TTV) was suggested to play a role in certain infections as a causative or coinfecting agent. AIMS: To investigate whether the development and progression of laryngeal squamous cell carcinoma is associated with coinfection with TTV and HPV. METHODS: The prevalence of TTV and HPV was investigated using the polymerase chain reaction in tissue samples from 40 healthy individuals, 10 patients with recurrent papillomatosis, five patients with papillomatosis with malignant transformation, and 25 patients with laryngeal carcinoma. The obtained prevalence data were compared and analysed statistically. RESULTS: In the 11 patients with carcinoma who had metastasis or relapse there was a high rate of coinfection with genogroup 1 TTV and HPV (eight of 11), whereas in the 14 without tumour progression no coinfection was found. Coinfection was associated with significantly lower tumour free survival in patients with carcinoma (p < 0.001). Furthermore, four of five patients who had papillomatosis with malignant transformation were coinfected with genogroup 1 TTV and HPV. CONCLUSIONS: Although the nature of cooperation between HPV and TTV needs to be investigated further, coinfection with genogroup 1 TTV and HPV appears to be associated with poor clinical outcome in laryngeal cancer.  相似文献   
995.
Three different monoclonal antibodies (MAb) against human immunoglobulin E have been obtained which specifically bind to human myeloma and polyclonal IgE. The antibodies showed high avidities for soluble IgE (0.7 X 10(9) to 3.3 X 10(9) M-1). These MAb defined three distinct epitopes on IgE. A mixture of these antibodies in combination with an 125I-labelled anti-mouse Kappa chain MAb has been used to measure allergen-specific IgE. This determination was performed by a solid-phase radioimmunoassay using allergen extracts coated to either chemically activated paper discs or to polyvinyl chloride wells. This method is 4-10 times more sensitive than other previously reported procedures. A similar technique has also been applied to detect individual allergens in immunoblots of allergen extracts.  相似文献   
996.
997.
998.
The prevalence of gastroesophageal reflux (GER) in asthmatic patients is elevated, but the exact frequency remains unknown. The relationship between GER and asthma has not been investigated in Mexico. The objective of this study is to know the frequency of GER in Mexican asthmatic patients and the possible relationship with the severity of asthma. Fifty patients with adult-onset asthma were studied. AII of them fulfill the diagnostic criteria of the National Institutes of Health, U.S. The evaluation included a symptoms questionnaire, spirometry, esophageal manometry, 24-h esophageal pH-recording, and an upper gastrointestinal endoscopy. Twenty-three patients had mild asthma (46%), 16 moderate (32%) and 11 had severe asthma (22%). Twenty-seven (54%) reported heartburn and regurgitation at least twice a week. The esophageal pH-recording showed pathologic GER in 37 subjects (74%) and endoscopic esophagitis was found in 7 cases (14%). The pH-recording showed pathologic GER in 13 patients with mild asthma (57%), in 13 with moderate asthma (81%) and in all patients with severe asthma (100%). The frequency of GER in Mexican asthmatic patients is high and increases proportionately with the severity of asthma. This factor must be considered in the integral evaluation of these patients.  相似文献   
999.
1000.
It is known that in severe nonthyroidal illness the regulation of thyroid function, the distribution and metabolism of thyroid hormones may change. The present study aimed at clarifying whether a change in the function of the pituitary-thyroid axis can be detected in an approximately homogeneous group of haematological patients, and how it is correlated with the various phases of the disease and with the therapeutic result. Studies were performed on patients with chronic and acute myelogenous leukaemia: serum levels of total thyroxine and triiodothyronine, free thyroxine and triiodothyronine, reverse triiodothyronine and thyrotropic hormone were determined. Apart from a few cases, there was no dysfunction of the pituitary-thyroid axis in chronic leukaemic patients being in the remission phase. However, the peripheral thyroxine metabolism may be altered. The longitudinal studies on acute myelogenous leukaemic patients indicate that, with the progression of the disease, serum TSH and thyroid hormone levels were reduced in a part of the cases and it is not justified to assess the free serum thyroxine level by an analogue-tracer method in this disease. The examinations have revealed that the various phases of the clinical picture as well as the therapeutic results considerably influence the function of the pituitary-thyroid axis. It seems reasonable to consider these findings in the other severe nonthyroidal illnesses as well.  相似文献   
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