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48 patients with stage I-II low-grade non-Hodgkin's lymphoma were treated by radiation and/or chemotherapy between 1970 and 1986. The histologic types were diffuse lymphocytic well differentiated, eleven patients; nodular lymphocytic poorly differentiated, 28 patients; nodular mixed, nine patients. Complete remission was obtained in 45 patients (94%). Overall survival was 83% and 68% at five and ten years, respectively. Five and ten-year relapse-free survival of complete responders was 71% and 57%, respectively. Univariate analysis of potential prognosticators showed the following to significantly increase the survival rate: one or two sites of disease (p less than 0.01), stage I (p less than 0.02), age less than 65 years (p less than 0.02), complete excision of tumor mass (p less than 0.03), and the use of radiotherapy (p less than 0.02). The extent of radiotherapy field did not affect survival. Multivariate analysis by the stepwise proportional hazards model of Cox showed that the use of radiotherapy was the factor which significantly produced better survival figures (p less than 0.03). It is concluded that two thirds of stage I-II low-grade lymphoma patients are potentially curable; radiotherapy plays a major role in the management.  相似文献   
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Background: The aim of this study was to examine the anti-inflammatory and anti-apoptotic patterns of omega-3 polyunsaturated fatty acids (n-3 PUFAs) during methotrexate (MTX) induced intestinal damage in cell culture and in a rat model. Methods: Non-treated and treated with MTX HT 29 and HCT116cells were exposed to increasing doses of n-3 PUFAs and cell viability was evaluated using PrestoBlue® assay. Male Sprague-Dawley rats were divided into 4 experimental groups: Control rats, CONTR+n-3 PUFA rats that were treated with oral n-3 PUFA, MTX rats were treated with MTX given IP, and MTX+n-3 PUFA rats were treated with oral n-3 PUFA before and following injection of MTX. Intestinal mucosal parameters and mucosal inflammation, enterocyte proliferation and apoptosis, TNF-α in mucosal tissue and plasma (ELISA), NF-κB, COX-2, TNF-α, Fas, FasL, Fadd, Bid, Bax and Bcl-2gene and protein levels were determined 72 h following MTX injection. Results: Exposure of HT 29 and HCT116cells to n-3 PUFA attenuated inhibiting effects of MTX on cell viability. MTX-n-3 PUFA rats demonstrated a lower intestinal injury score and enhanced intestinal repair. A significant decrease in enterocyte apoptosis in MTX+n-3 PUFA rats was accompanied by decreased TNF-α, FAS, FasL, FADD and BID mRNA levels. Decreased NF-κB, COX-2 and TNF-α levels in mucosa was accompanied by a decreased number of IELs and macrophages. Conclusions: n-3 PUFAs inhibit NF-κB/COX-2 induced production of pro-inflammatory cytokines and inhibit cell apoptosis mainly by extrinsic pathway in rats with MTX-induced intestinal damage.  相似文献   
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A novel serum 21 kDa haptoglobin-related protein (Hpr) was investigated in patients with malignant lymphoma, to evaluate its correlation with clinical and histologic features at presentation and its possible role as a tumor marker for patient outcome. One hundred fifty eight serum samples were taken from 88 patients with non-Hodgkin’s lymphoma (n=58) and Hodgkin’s disease (n=30) at presentation and in the course of follow-up. Sera from 61 healthy volunteers served as normal controls. Serum Hpr levels in the lymphoma patients (median 430xl03 u/ml, range 0-4000xl03) were significantly higher than in the control group (median 68xl03 u/ml, range 0-180xl03) (p=0.0001). Higher median Hpr values were detected in patients with advanced disease (p=0.013), “B” symptoms (p=0.029) and in males (p=0.053). There was also a significant correlation between Hpr and erythrocyte sedimentation rate (p=0.028). Serial determinations showed a significant decrease of the initial Hpr values obtained after treatment in 41 patients, 38 of whom achieved complete remission. In the follow-up period additional Hpr measurements were taken from 17 patients. Three of them eventually relapsed, and showed increased Hpr levels at the time of relapse. Hpr levels remained low in 11 of 14 patients who maintained complete remission, and increased in three. In conclusion, serum Hpr is a new serum tumor marker of potential use in the clinical setting of lymphoma. This work is dedicated to the memory of Dr. Arie H. Bartal, a dedicated oncologist and friend. This work was supported by Chemotech Thechnologies Ltd., by grant no. 3676 from the Chief Scientist’s Office of the Ministry of Health, Israel, and by the Fund for Promotion of Research in the Technion.  相似文献   
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The D1 protein of the photosystem II (PSII) complex in the thylakoid membrane of oxygenic photosynthetic organisms is synthesized as a precursor polypeptide (pD1) with a C-terminal extension. Posttranslational processing of the pD1 protein is essential to establish water oxidation activity of the PSII complex. We have recently identified a gene, ctpA, a mutation in which resulted in a loss of PSII activity in the cyanobacterium Synechocystis sp. PCC 6803. To study the function of the CtpA protein, we inactivated the ctpA gene by inserting a kanamycin-resistance gene into its coding sequence. The resultant mutant strain, T564, had no PSII-mediated water oxidation activity, but it had normal cytochrome b6f and photosystem I activities. Measurements of thermoluminescence profiles and rates of reduction of 2,6-dichlorophenolindophenol indicated that PSII complexes in the mutant cells had functional reaction centers that were unable to accept electrons from water. Immunoblot analysis showed that D1, D2, CP47, CP43, and the alpha subunit of cytochrome b559, five integral membrane proteins of PSII, were present in T564 cells. Interestingly, the D1 protein in the mutant cells was 2 kDa larger than that in wild-type cells, due to the presence of a C-terminal extension. We conclude that the CtpA protein is a processing enzyme that cleaves off the C-terminal extension of the D1 protein. Interestingly, the CtpA protein shows significant sequence similarity to the interphotoreceptor retinoid-binding proteins in the bovine, human, and insect eye systems.  相似文献   
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Foveal hypoplasia, always accompanied by nystagmus, is found as part of the clinical spectrum of various eye disorders such as aniridia, albinism and achromatopsia. However, the molecular basis of isolated autosomal recessive foveal hypoplasia is yet unknown. Individuals of apparently unrelated non consanguineous Israeli families of Jewish Indian (Mumbai) ancestry presented with isolated foveal hypoplasia associated with congenital nystagmus and reduced visual acuity. Genome-wide homozygosity mapping followed by fine mapping defined a 830 Kb disease-associated locus (LOD score 3.5). Whole-exome sequencing identified a single missense mutation in the homozygosity region: c.95T>G, p.(Ile32Ser), in a conserved amino acid within the first predicted transmembrane domain of SLC38A8. The mutation fully segregated with the disease-associated phenotype, demonstrating an ∼10% carrier rate in Mumbai Jews. SLC38A8 encodes a putative sodium-dependent amino-acid/proton antiporter, which we showed to be expressed solely in the eye. Thus, a homozygous SLC38A8 mutation likely underlies isolated foveal hypoplasia.  相似文献   
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