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11.
Electrophoretic patterns of human and dog plasma are markedly altered by the extraction of a large part of the plasma lipids. Total electrophoretic areas, relative areas of individual electrophoretic components, and electrophoretic albumin: globulin ratios undergo change. For human plasma, such extractions confirm previous observations that a particularly rich lipid content characterizes beta globulin. Abnormally large beta peaks regularly occur in the presence of elevated plasma lipids. Marked increases in gamma globulin, however, are also found to be due in large part to elevated plasma lipid levels in certain abnormal human plasmas. The greatest relative amount of lipid in dog plasma, in contrast to human plasma, is associated not with the beta globulin, but with components usually designated as alpha globulins. Not only the areas, but the configuration and the number of alpha globulin peaks in dog plasma are altered by the extraction of plasma lipids. The results demonstrate that increased alpha globulin areas which occur in the plasma of hypoproteinemic dogs are due in large part to elevated plasma lipid levels.  相似文献   
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Mycobacterium genavense infection, a rare nontuberculous mycobacteria infection, occurs in heavily immunocompromised patients (i.e., those with advanced HIV disease, genetic disorders, or acquired immunologic disorders and those undergoing immunosuppressive therapy). We report a case of disseminated M. genavense infection preceding Hodgkin lymphoma in a patient without obvious risk factors for this infection.  相似文献   
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Immune reconstitution was studied prospectively in 66 children who underwent 77 haematopoietic cell transplantations (HCT): 46 autologous HCTs in 39 patients and 31 allogeneic HCTs in 27 patients. We studied the dynamic analysis of immune recovery with regard to potential factors affecting its speed, including age, type of HCT, diagnosis, graft-versus-host disease (GvHD) and cytomegalovirus (CMV) infection reactivation. Absolute counts of different lymphocyte subsets and immunoglobulin serum levels were determined in peripheral blood of patients on d -7 and +16, and then at various intervals up to 24 months post transplant. Common patterns of immune recovery after both allogeneic and autologous HCT were identified: (i) CD4+CD45RO+ peripheral T-cell expansion on d +16; (ii) inverted CD4+:CD8+ ratio from d +30 onwards; (iii) rapid natural killer (NK) cell (CD16+/-CD56+) count normalization. We observed prolonged T-cell lymphopenia (CD3+, CD3+CD4+, CD4+CD45RA+) until 24 months after autologous HCT, whereas in the allogeneic setting CD3+CD4+ cells, including naive CD45RA+ cells, returned to normal values at 9 months post transplant. Age > 10 years and coexistence of GvHD and CMV reactivation were associated with a substantial delay in T- (CD4+, including CD45RA+) and B-cell recovery after allogeneic HCT. Multidrug GvHD prophylaxis resulted in impaired T- (CD4+, CD4+CD45RA+) and B-cell reconstitution only in the early phase after allogeneic HCT (up to 4 months). Our results demonstrated that T-cell recovery was severely impaired in children after autologous HCT. It should be emphasized that specific approaches to enhance immune reconstitution are necessary to control minimal residual disease and avoid the risk of infectious complications in the autologous setting. Thymic involution after allogeneic HCT seems to be associated with age and coexistence of GvHD and CMV reactivation.  相似文献   
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BACKGROUND: Although Helicobacter pylori is a significant etiologic factor of peptic ulcer disease, it remains unknown why ulcers develop only in the minority of infected individuals. AIM: The aim of this cross-sectional study was to evaluate the association between the presence of duodenal ulcer in H. pylori-infected patients and different risk factors. METHODS: A total of 122 H. pylori-infected patients were enrolled; 79 had duodenal ulcer and 43 gastritis. Univariate analysis was conducted using either Fisher's exact test or exact Cochrane-Armitage trend test. In multivariate analysis the logistic model was used. RESULTS: Univariate analysis indicated six factors (male sex, smoking, antral H. pylori density, CAGA presence in antrum, and VACA s1a presence in antrum and corpus). Four factors (sex, smoking-alcohol index, H. pylori density index, and CAGA index) were found to be significant in multivariate analysis. The best model predicting duodenal ulcer included male sex, smoking, presence of H. PYLORI on histopathology in antrum and CAGA presence in corpus. CONCLUSION: Although several risk factors were significantly associated with duodenal ulcer, we failed in the identification of either a single risk factor or a set of factors that can unequivocally differentiate patients with ulcer from those with gastritis.  相似文献   
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Objective:To compare the incidence of upper eyelid blepharoptosis after combined phacotrabeculectomy with mitomycin C and phacoemulsification surgeries and the relationship of bleb morphology to the incidence of ptosis.Design:Retrospective observation study.Participants:We included 46 patients after combined phacotrabeculectomy and 44 patients with phacoemulsification in the former group, and all eyes underwent a standardized two-site surgery with intra-operative mitomycin C.Results:There were 8 eyes (17.4%) and 5 eyes (11.4%) with postoperative ptosis in the phacotrabeculectomy and phacoemulsification groups, respectively (P = 0.342). In multivariate regression analysis, reduced total bleb area was significantly associated with upper eyelid ptosis after adjusting for age, gender, and type of anesthesia. The trend seemed to show that increased bleb height was also associated with ptosis, but this did not reach statistical significance.Conclusions:Incidence of persistent ptosis after phacoemulsification combined with trabeculectomy and mitomycin C is similar compared to stand alone phacoemulsification surgery in a multiethnic Asian population. Bleb morphology may play an important role in postoperative ptosis development and should be considered in the evaluation of upper eyelid blepharoptosis.  相似文献   
17.
N-nitrozodimethyloamine (NDMA) is a carcinogenic compound that can be formed in vivo. NDMA is synthesized from precursors-amines and nitrosating agents. Nitrosating agents are formed through the reaction of oxide, reactive oxygen species and nitric oxide (NO). Human neutrophils (PMN) are an important source of the most reactive oxygen species as well as of the nitric oxide. The increase in oxygen metabolism of PMN can lead to the increase nitrosating agent and nitroso-forms. Inflammatory process is associated with locally decreased pH that may favor nitrosation reaction.

In the present study, we estimated the NDMA synthesis by LPS-stimulated PMN in the presence of the iNOS inhibitor – N-nitro-L-arginine methyl ester (L-NAME). In the nitrosation reaction dimethylamine (DMA) was used as substrat. The viability of the cells was measured by cytometric method. NDMA concentrations the culture media was measured by GCMS method. NO production was estimated by Griess's method. Expression of iNOS was determined by western blotting.

Results obtained showed that DMA nitrosation is most effective in pH between 3–4.5. Nonstimulated PMN produced lower concentrations of NO than LPS-stimulated cells (1.27 μg/cm3 and 1.57 μg/cm3, respectively). In the culture of nonstimulated PMN supplemented with DMA, there was NDMA (mean – 0.99 ng/cm3). In the culture of LPS-stimulated PMN in the presence of DMA, the concentration of NDMA was higher than in the culture of nonstimulated PMN (median – 1.45 ng/cm3). In the supernatants of cells incubated without DMA and with DMA, LPS and L-NAME, no NDMA was detected. These results indicate that PMN can be one of sources of nitrosating agents and can play a role in endogenous NDMA synthesis. Stimulation of PMN can lead to the increase of NDMA concentration following the increase of NO production. Different pathological conditions associated with PMN activation as well as the decreased pH may favor endogenous NDMA synthesis.  相似文献   
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Restless legs syndrome (RLS) is a common multifactorial disease. Some genetic risk factors have been identified. RLS susceptibility also has been related to iron. We therefore asked whether known iron-related genes are candidates for association with RLS and, vice versa, whether known RLS-associated loci influence iron parameters in serum. RLS/control samples (n=954/1814 in the discovery step, 735/736 in replication 1, and 736/735 in replication 2) were tested for association with SNPs located within 4 Mb intervals surrounding each gene from a list of 111 iron-related genes using a discovery threshold of P=5 × 10−4. Two population cohorts (KORA F3 and F4 with together n=3447) were tested for association of six known RLS loci with iron, ferritin, transferrin, transferrin-saturation, and soluble transferrin receptor. Results were negative. None of the candidate SNPs at the iron-related gene loci was confirmed significantly. An intronic SNP, rs2576036, of KATNAL2 at 18q21.1 was significant in the first (P=0.00085) but not in the second replication step (joint nominal P-value=0.044). Especially, rs1800652 (C282Y) in the HFE gene did not associate with RLS. Moreover, SNPs at the known RLS loci did not significantly affect serum iron parameters in the KORA cohorts. In conclusion, the correlation between RLS and iron parameters in serum may be weaker than assumed. Moreover, in a general power analysis, we show that genetic effects are diluted if they are transmitted via an intermediate trait to an end-phenotype. Sample size formulas are provided for small effect sizes.  相似文献   
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