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The modulation of drug metabolising enzymes by Masheri extract (ME) and Benzo(a)Pyrene [B(a)P] was studied in male Sprague Dawley rats fed different dietary protein levels. Two groups of 21 days old male Sprague Dawley rats were put on a high protein diet (SHP) with 20% Casein, and a low protein diet (SLP) with 3% Casein semisynthetic based diets for 12 weeks. The SLP fed animals showed lower basal levels of the Phase I activating enzymes viz. Cytochrome P450, Benzo(a)Pyrene hydroxylase, Benzphetamine demethylase and Phase II glutathione detoxification system viz. Glutathione (GSH) and Glutathione-S-transferase. ME and B(a)P treatment significantly depleted the glutathione detoxification system in the SLP group whereas an opposite effect was observed in the SHP group. Interstingly, ME and B(a)P treated rats in the SLP group showed a higher percent increase in the hepatic and pulmonary Phase I enzyme activities than those observed in the treated ME/B(a)P treated SHP rats. Furthermore, both ME and B(a)P significantly decreased the hepatic pool of vitamin A while a concomittant increase in that of vitamin C was observed.  相似文献   
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Mast cells are now known to derive from CD34+ haemopoietic stem cells in the bone marrow. However, it has not yet been established whether the various types of mastocytosis, which involve tumour-like proliferation of mast cells, are true neoplastic disorders or reactive/hyperplastic conditions. In this study, tissue specimens (five bone marrow, two spleen, one skin) from female patients with histologically confirmed mastocytosis were investigated with a recently developed polymerase chain reaction assay for the determination of clonality of female cells using the human androgen receptor gene (HU-MARA). Mast cells purified to near homogeneity from hysterectomy specimens served as a control. The findings in bone marrow and skin either were not reproducible, or indicated polyclonality. However, both spleen specimens exhibited monoclonality. In addition, DNA analysis by flow cytometry was performed and revealed a diploid chromosome content with proliferation indices of under 8% in all the specimens. This is the first molecular biological study to indicate that mastocytosis is indeed neoplastic in nature.  相似文献   
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AIMS: To investigate whether plasma cell expression of early B cell, late B cell/preplasma cell, T cell, and myelomonocytic antigens or myeloma associated lymphocytic infiltrates correlated with prognosis in bone marrow biopsy specimens of patients with multiple myeloma. METHODS: Bone marrow biopsy specimens of 23 patients with multiple myeloma were investigated for plasma cell expression and interstitial lymphocyte expression of T cell related antigen CD45RO (UCHL-1). RESULTS: Eight patients showed plasma cell expression of CD45RO and 16 showed increased tumour infiltrating CD45RO positive lymphocytes, which were correlated with poor survival by multivariate analyses (p = 0.005 and p = 0.04, respectively). B cell antigens (MB2, CD20) but no T cell specific antigens (CD3) or T cell receptor gene rearrangements were expressed by plasma cells in CD45RO positive myelomas. Of 16 patients with myeloma who had increased tumour infiltrating CD45RO positive lymphocytes, four had interstitial lymphocyte expression of B cell antigens and two had interstitial lymphocyte expression of the T cell specific antigen CD3. CONCLUSIONS: The recognition of plasma cell expression of CD45RO and increased interstitial CD45RO lymphocytes in bone marrow biopsy specimens of patients with multiple myeloma is an adverse prognostic finding not indicative of an aberrant T cell phenotype or genotype; it is consistent with B cell/pre-plasma cell antigen expression by myeloma cells and their lymphocytic precursors.  相似文献   
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In order to overcome the continuing infection rate associated with biomaterials, the use of covalently bound furanones as an antibiofilm coating for biomaterials has been investigated. Furanones have previously been shown to inhibit growth of Gram-positive and Gram-negative bacteria. The aim of these studies were to covalently bind furanones to polymers and to test their efficacy for inhibiting biofilm formation of Staphylococcus epidermidis and in vivo infection rate. Two methods of covalent attachment of furanones were used. The first, a co-polymerisation with a styrene polymer, and second, a plasma-1-ethyl-3-(dimethylaminopropyl) carbodiimide (EDC) reaction to produce furanone-coated catheters. Biofilm formation by S. epidermidis in vitro was inhibited by 89% for polystryene-furanone disks and by 78% by furanone-coated catheters (p<0.01). In an in vivo sheep model we found furanones were effective at controlling infection for up to 65 days. Furanones have potential to be used as a coating for biomaterials to control infection caused by S. epidermidis.  相似文献   
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PURPOSE: To assess the Heidelberg Retina Flowmeter (HRF) parameters "volume", "flow", and "velocity", at the papilla in healthy subjects. METHODS: HRF measurements were taken at the papilla (5 degrees x 20 degrees), superficially at level of the retina and at the bottom of the excavation. The effect of increasing frame size (1 x 1 to 50 x 50 pixels) on HRF values was assessed in ten subjects. HRF parameters were calculated (50 x 50 pixels) for 150 eyes of 150 subjects. To assess short-term reliability, measurements were repeated five times in ten subjects. RESULTS: With 50 x 50 pixels the location of the frame had no influence on HRF values. Reliability was > 90%. Values were significantly higher (p < 0.001) in the superficial than in the deeper papillary layers. The correlation between HRF parameters was good (r2 > 0.85). CONCLUSIONS: A low magnification (5 degrees x 20 degrees) and a 50 x 50 frame allows a global assessment of HRF parameters at the papilla with high reliability. In healthy eyes, the HRF values are influenced by the level where measurements are made at the papilla. This might be of importance in glaucoma patients with excavated papilla.  相似文献   
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The many smoking-induced changes are diffuse and include, but are not limited to, coronary artery disease and cerebrovascular accidents. Cigarette smoking has even been suggested to be an important risk factor in the development of nonarteritic anterior ischemic optic neuropathy. The purpose of the present investigation was to compare confocal scanning laser Doppler flowmeter parameters between otherwise healthy smokers and healthy nonsmokers. Confocal scanning laser Doppler flowmeter parameters were assessed in 58 healthy non-smokers and 20 otherwise healthy smokers in a middle-aged population. An analysis of covariance (covariate: age) disclosed decreased values for all confocal scanning laser Doppler flowmeter parameters (`Volume': p&lt;0.036; `Flow': p&lt;0.019; `Velocity': p&lt;0.023) in smokers. The present study suggests that healthy smokers might have reduced confocal scanning laser Doppler flowmeter parameters at the optic nerve.  相似文献   
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Summary Two cases of soft tissue sarcoma following treatment of nodular sclerosing Hodgkin's disease are described. One patient developed a malignant schwannoma after radiotherapy, the other was diagnosed as having a malignant fibrous histiocytoma after treatment with radiation and chemotherapy. Both secondary malignancies arose within the irradiated field after a latent period rangig from 9.5 years in the first to 21 years in the second case. A review of the pertinent literature is given and previous reports of malignant tumors and leukemias following therapy for Hodgkin's disease are summarized.  相似文献   
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