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41.
Paul R. Atkinson Jeffrey L. Mahon John Dupre Calvin R. Stiller Morris R. Jenner Terri L. Paul Clement I Momah 《Journal of autoimmunity》1990,3(6):793-799
Although cyclosporine A (Cy-A) is effective in modifying the initial course of newly diagnosed insulin dependent diabetes mellitus (IDDM) it has a number of side effects, particularly renal, which limit its use. In this study we investigated the potential synergistic effects of bromocriptine (BCR) therapy in treating patients with newly diagnosed IDDM. Three groups of patients were treated: (1) fourteen patients on Cy-A who required a decrease in their dose due to elevated creatinine; (2) four newly diagnosed patients whose initial therapy consisted of low dose (5 mg/kg/day) Cy-A and 10 mg/day of BCR; (3) eight patients whose glucagon-stimulated connecting-peptide (C-peptide) levels were greater than 0.3 nmol/l but whose insulin requirements were over 0.3 U/kg/day and whose Cy-A was to be discontinued. The results suggest that there was no statistically significant difference in stimulated C-peptide, glycosylated haemoglobin, daily insulin dose or serum creatinine. However, the trend suggested that BCR may have some protective effect on preserving endogenous insulin secretory capacity, although glycosylated haemoglobin and daily insulin dose increased. The results do not suggest that patients with newly diagnosed IDDM significantly benefit from concurrent BCR and Cy-A therapy. 相似文献
42.
Cell membrane proteins encoded for by the major histocompatibility complex (MHC)1 are associated with the antigenic determinant(s) recognized on trinitrophenyl (TNP)-modified cells by syngeneic murine cytotoxic T lymphocytes and by hapten-reactive guinea pig T cells. To investigate the relationship of the TNP moiety on TNP-modified cells to these major histocompatibility antigens, peritoneal exudate cells or splenocytes from two inbred guinea pig strains and one inbred murine strain were TNP-modified, radioiodinated and lysed in detergent. TNP-derivatized proteins were then isolated using an anti-TNP immunoabsorbent, and the presence on TNP-derivatized histocompatibility antigens in the eluted proteins was determined by immunoprecipitation experiments and SDS-polyacrylamide gel electrophoretic analysis. Whereas most of the various histocompatibility antigens examined were found to be TNP-derivatized in amounts proportional to the degree of membrane protein derivation as a whole, only small amounts of TNP-modified strain 2 guinea pig Ia antigens were found, and no hapten-modified strain 13 guinea pig Ia antigens were detected. It is concluded that, in contrast to most MHC gene products, strain 13 Ia antigens are not derivatized on TNP-modified cells and, thus, represent an important exception demonstrating that histocompatibility antigens need not be directly TNP-derivatized for T cell recognition and activation. 相似文献
43.
Background
The primary aim was to assess survival of opening wedge high tibial osteotomy (HTO) for medial compartment osteoarthritis. The secondary aim was to identify independent predictors of early conversion to total knee arthroplasty (TKA).Methods
During the 18-year period (1994–2011) 111 opening wedge HTO were performed at the study centre. Mean age was 45 years (range 18–68) and the majority male (84%). Mean follow-up was 12 (range six to 21) years. Failure was defined as conversion to TKA. Kaplan–Meier, Cox regression and receiver operating curve (ROC) analyses were performed.Results
Forty (36.0%) HTO failed at a mean of 6.3 years (range one to 15). By Kaplan–Meier analysis, the five-year survival rate was 84% (95% confidence interval (CI) 82.6–85.4), 10-year rate 65% (95% CI 63.5–66.5) and 15-year rate 55% (95% CI 53.3–56.7). Cox regression analysis identified older age (hazard ratio (HR) 1.07 for each additional year, 95% CI 1.03–1.11, p b 0.001) and female gender (HR 2.37, 95% CI 1.06–5.33, p?=?0.04) as independent predictors of failure. ROC analysis identified a threshold age of 47 years above which the risk of failure increased significantly (area under curve 0.72, 95% CI 0.62–0.81, p b 0.001). Cox regression analysis, adjusting for covariates, identified a significantly greater (HR 2.49, 95% CI 1.26–4.91, p?=?0.01) risk of failure in patients aged 47 years old or more.Conclusion
The risk of early conversion to TKA is significantly increased in females and those older than 47. These risk factors should be considered pre-operatively when planning intervention for isolated medial compartment osteoarthritis. 相似文献44.
Collagenous spherulosis of the breast 总被引:2,自引:0,他引:2
Fifteen examples of a hitherto undescribed lesion, which we have designated "collagenous spherulosis," were encountered in breast tissue from women aged 39 to 55 years. The lesion, which was multifocal in eight cases, was an incidental microscopic finding involving lobular acini and ductules, and consisted of intraluminal clusters of eosinophilic spherules measuring approximately 20-100 mu in diameter. The spherules typically were found, and appeared to originate, within the spaces of fenestrated epitheliosis ("papillomatosis"). Special stains indicated that the spherules were collagen-rich, but also contained variable amounts of acidic mucin, PAS-positive, basement membrane-like material, and elastin. With immunoperoxidase staining, the cells immediately surrounding the spherules stained positively for actin, suggesting myoepithelial differentiation. Collagenous spherulosis was typically situated adjacent to, or encompassed by, other benign proliferative processes, including intraductal papillomas, sclerosing adenosis, and "infiltrating epitheliosis" (radial scars). Collagenous spherulosis is a clinically and histologically benign lesion that on microscopic examination has been confused with--and should be distinguished from--malignant lesions including adenoid cystic carcinoma of the breast and so-called intraductal signet-ring carcinoma. 相似文献
45.
46.
X Chanudet A Py H Journo P Jaillais J M Garcin R Clement P Larroque 《Archives des maladies du coeur et des vaisseaux》1990,83(8):1169-1174
Regional blood flow measurement in the limbs (BFLL) is of special interest in order to evaluate the consequences of hypertension. The purpose of this study is to assess the interest of the Doppler ultrasound method in the BFLL measurement among normotensive or borderline hypertensives young male adults. BFLL reproducibility was evaluated among 23 healthy subjects aged 21 +/- 2 y, height 177 +/- 8 cm, weight 75 +/- 13 kg at day one (D1) and three day later (D3). Measurements were made basically after 20 minutes lying at rest and after cold pressor test (CPT). BFLL estimation depends on common femoral artery diameter (FAD) echographic measurement at the thigh root and on velocity time interval (VTI) calculation with pulsed wave doppler using controlled incident angle and sample volume. The following parameters were measured: mean arterial pressure (MAP) using Dinamap, heart rate (HR), FAD, common femoral artery cross sectorial area (A), VTI and peripheral arteriolar resistances (PAR). Basic and CPT results at D1 and D3 were compared using paired "t" test. Results: [table: see text] Comparisons between basic state and CPT demonstrate a significant decrease of VTI and BFLL, a significant increase of PAR. D remained unchanged. Doppler ultrasound method is easy to use. Systolic femoral volume measurement is relatively insensitive to small transducer positioning variations so that the method reproducibility is satisfactory. 相似文献
47.
48.
To assess the impact of surgical stimulation on regulation of ventilation in anaesthetized man, we measured ventilation and the ventilatory responses to either hyperoxic hypercapnia or to isocapnic hypoxaemia in fifteen subjects anaesthetized with enflurane 1.1 MAC, just prior to and then during a surgical procedure. Anaesthesia alone reduced ventilation, increased Paco2 decreased the response to carbon dioxide and virtually abolished the response to hypoxaemia. The addition of operation at the same level of anaesthesia augmented ventilation and reduced Paco2 but did not improve the anaesthesia-induced impairment of the responses to hypercarbia and hypoxaemia. Over the range of PCO2 and PO2, values studied, the effects of surgery were constant and independent of chemical drive. A.M. Lam, M.D., Resident; J.L. Clement, R.N.; R.L. Knill, M.D., F.R.C.P.(C), Associate Professor; Department of Anaesthesia, University Hospital, University of Western Ontario, London, Canada. This work was supported by the Medical Research Council of Canada, Development Grant 150. Address reprint requests to Dr. R.L. Knill, Department of Anaesthesia, University Hospital, 339 Windermere Road, London, Ontario, Canada, N6A 5A5. 相似文献
49.
50.
Peer K. Lilleng Odd R. Monge Anders Wall e Clement S. Trovik Markus Hordvik Johan H ie Olav Dahl Gisle Bang 《Acta oncologica (Stockholm, Sweden)》1997,36(4):438-440
Fibrosarcoma is a rare tumour in children. The potential of malignancy has been questioned. We present three cases of fibrosarcoma in children. The follow-up periods range from 10 to 37 years. The first patient had pulmonary metastases at the time of diagnosis in 1958. The primary tumour in fossa ischio-rectalis was resected in 1960. Lung metastases were resected in 1960 and 1989. Radiotherapy was given in 1992. He is still alive with metastases 37 years after the first manifestation of disease. The second patient had a primary tumour and several local recurrences in the mandible. He is alive without evidence of disease 4 years after resection of pulmonary metastases and 21 years after resection of the primary tumour. The third patient has no signs of recurrence or metastasic spread 10 years after a wide excision of subcutanous tumours of the left upper arm. The cases demonstrate a special tumour-entity of low-grade malignancy, which show a good prognosis and a wide spectrum of biological behaviour. 相似文献