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21.
We have investigated the cellular and serum CK18 in 26 non-treated primary ductal invasive breast carcinomas. The soluble CK18 (TPS) was detected by chemiluminescent assay, and the cellular CK18 and PCNA expression by immunocytochemistry. Flow-cytometry was used to estimate the amount of DNA in malignant cells. There was a significant correlation between soluble CK18 and the pre-menopausal status (p < 0.05), characterized in our group by a PCNA estimated low proliferation index. We have also found a significant correlation between soluble CK18 and the DNA index (p < 0.01). The intracellular CK18 has correlated with the PCNA expression (p < 0.05), while no correlation could be found between cellular and serum CK18. The values of soluble CK18 may offer information about the treatment-induced cell death, if monitored, while isolated measurements should be interpreted cautiously. Elevated levels of serum CK18 in non-treated carcinomas may rather reflect a high tumor turn-over or perhaps a more intensive tumor cell killing.  相似文献   
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BACKGROUND: Epoetin alfa, administered at standard dosages of 10,000-20,000 IU three times weekly or 40,000-60,000 IU once weekly, has been shown to significantly increase hemoglobin (Hb) levels, decrease transfusion requirements, and improve quality-of-life parameters in patients undergoing chemotherapy.Objective. This open-label, nonrandomized, historically controlled study was conducted to evaluate the efficacy and safety of an induction dose of epoetin alfa in patients with moderate or severe anemia who were receiving chemotherapy. METHODS: Nineteen patients with solid tumors and Hb levels < 9.0 g/dl were enrolled. The patients received single s.c. injections of epoetin alfa, 40,000 IU, on study days 1, 4, 7, 10, and 13, and were then observed for the following 30 days. Nineteen other cancer patients who had matching characteristics and had received epoetin alfa, 10,000 IU, three times weekly for the 45-day study period, served as historical controls. The primary efficacy variable was change in Hb level from baseline to days 15 (approximately week 2) and 45 (approximately week 6.5). Secondary efficacy variables included the percent response (Hb increase > or = 1 g/dl) and percent major response (Hb increase > or = 2 g/dl) at days 15 and 45, the durations of response and major response after day 45, the proportion of patients transfused within the 45 study days, the changes in Eastern Cooperative Oncology Group performance status score at days 15 and 45, and the ability to maintain the planned chemotherapy dose (dose intensity) over the 45-day study. RESULTS: Mean increases in Hb level in the epoetin alfa 40,000 IU group were significantly greater than those in the historical control group both at day 15 and at day 45. The increase in Hb level in the control group approximated increases reported with standard 3-times-weekly epoetin alfa at day 15 but was somewhat lower than the increases typically seen by day 45, presumably due to the fact that, in the present study, the epoetin alfa dose was not doubled in initial nonresponders, as is commonly done with standard epoetin alfa treatment. The rates of major response for epoetin alfa 40,000 IU patients (37% at day 15 and 84% at day 45) were higher than those for control patients (16% and 21%, respectively). Also, the transfusion rate was lower and performance status scores were better in the epoetin alfa 40,000 IU patients than in the control patients. In all, 74% of epoetin alfa 40,000 IU patients versus 47% of control patients received 100% of the planned chemotherapy dose. Epoetin alfa was well tolerated in both treatment groups. CONCLUSIONS: Results of this study suggest that epoetin alfa at a dose of 40,000 IU administered five times over 2 weeks may confer even higher response rates than those seen with standard dosing regimens. These encouraging results support further study of the proposed induction dose of epoetin alfa in a larger, randomized, prospectively controlled trial.  相似文献   
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OBJECTIVES: T-cell mediated immune response to dietary gluten and cytokines release are important for the enteropathy seen in celiac disease. We investigated the serum levels of soluble interleukin-2 receptor, interleukin-6, and tumor necrosis factor-alpha in celiac children before and after gluten exclusion. METHODS: Cytokine levels were determined using enzyme immunoassay in serum from 12 untreated celiac patients, 16 treated celiac patients on a gluten-free diet for at least two years, and from 26 control children. Eight of 12 untreated patients were also investigated at 6 and 12 months after gluten exclusion. Serum IgA antiendomysium antibodies were also assayed by indirect immunofluorescence. RESULTS: Soluble interleukin-2 receptor and interleukin-6 levels were significantly increased in untreated celiac patients compared with treated and control children. There was no difference in the tumor necrosis factor-alpha levels between the groups. Soluble interleukin-2 receptor levels were the only ones significantly decreased at 12 months after gluten exclusion. However, soluble interleukin-2 receptor and interleukin-6 levels at 12 months were significantly higher compared with controls. Antiendomysium antibodies had a diagnostic sensitivity of 100% and the titers decreased significantly after 12 months of gluten exclusion. A significant positive correlation was found between antiendomysium antibody titers with both soluble interleukin-2 receptor and interleukin-6 values. CONCLUSIONS: The serum soluble interleukin-2 receptor and interleukin-6 levels may be used as a noninvasive measure of celiac disease activity and response to treatment.  相似文献   
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The Joint Committee on Infant Hearing (JCIH, 2000) has presented principles and guidelines for universal newborn hearing screening and early hearing detection and intervention (EHDI). The guidelines describe the need for a national data set for early hearing detection and intervention. The guidelines fail to provide the specific constructs for such a data set. To the authors' knowledge, no nationally proposed uniform data structure exists to capture EHDI services' outcome metrics. This article presents a proposed newborn hearing screening and EHDI data model. This model was developed to record EHDI outcomes data from Military Health System birthing centers. The data are to be collected for tracking implementation of Healthy People 2010 goals related to newborn hearing screening and EHDI programs within the Military Health System. In this article, the authors use the T. Helfer, A. Shields, and K. Gates (2000) methods to model a uniform structure for collection of newborn hearing screening and EHDI data. They also discuss expansion of the data model for application to public health reporting of EHDI outcomes in the civilian sector to include integration of Census Bureau demographic data and geographic information system data to further enhance the research value of these EHDI outcomes data. They offer the data model with the intention of supporting national research efforts for studying the efficacy of EHDI programs and to help establish a national evidence-based practice database for such programs.  相似文献   
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The goal of the study was to establish if there was a relationship between molecular patterns and virus evolution. Therefore the complete genome sequence of two distinct apathogenic Newcastle disease virus (NDV) strains was determined and a third genome size category, containing 15,198 nucleotides, was recognized. Phylogenetic analysis revealed that two major separations resulting in three genome size categories occurred during the history of NDV. An ancient division in the primordial reservoir (wild waterbird species) led to two basal sister clades, class I and II, with genome sizes 15,198 (due to a 12 nucleotide insert in the phosphoprotein gene) and 15,186 nucleotides, respectively. Ancestors of only class II viruses colonized chicken populations and subsequently converted to virulent forms. These took place more than once and resulted in an early lineage [including genotypes I–IV and H33(W)] with genome size of 15,186 nucleotides. A second division occurred in the 20th century in the secondary (chicken) host. This gave rise to the branching-off of a clade (including recent genotypes V–VIII consisting of only pathogenic viruses) with the concomitant insertion of six nucleotides into the 5′ non-coding region of the nucleoprotein gene thereby increasing the genome size to 15,192 nucleotides.  相似文献   
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Most quantitative research methods are based on measuring either the total or the free concentration of an analyte in a sample. However, this is often insufficient for the study of complex biological systems. The main objective of this research was to develop new methods for providing more information from samples: the free concentration (Cf), the total concentration (Ct), and the plasma binding capacity (PBC). Samples were processed using microextraction and ultrafiltration. For each of these techniques, two quantification procedures were used: addition of isotopically labeled standard and repeated analysis of the same sample. The new methods were validated by analyzing clinical samples and samples with known concentrations. Methods based on addition of labeled compound were found to be the fastest, and most reproducible. For analysis of clinical samples, methods based on microextraction were more sensitive and more accurate than those based on ultrafiltration. For analysis of pooled plasma samples, the overall accuracy of all approaches to determine PBC, testosterone Cf, and testosterone Ct was between 94 and 109%, 87–113%, and 94–122% respectively. The new approach goes beyond a simple concentration measurement, giving more information from clinical samples, with great potential for personalizing drug dosage and therapy to the needs of individual patients.  相似文献   
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Cerebrospinal fluid administration of recombinant adeno-associated viral (rAAV) vectors has been demonstrated to be effective in delivering therapeutic genes to the central nervous system (CNS) in different disease animal models. However, a quantitative and qualitative analysis of transduction patterns of the most promising rAAV serotypes for brain targeting in large animal models is missing. Here, we characterize distribution, transduction efficiency, and cellular targeting of rAAV serotypes 1, 2, 5, 7, 9, rh.10, rh.39, and rh.43 delivered into the cisterna magna of wild-type pigs. rAAV9 showed the highest transduction efficiency and the widest distribution capability among the vectors tested. Moreover, rAAV9 robustly transduced both glia and neurons, including the motor neurons of the spinal cord. Relevant cell transduction specificity of the glia was observed after rAAV1 and rAAV7 delivery. rAAV7 also displayed a specific tropism to Purkinje cells. Evaluation of biochemical and hematological markers suggested that all rAAV serotypes tested were well tolerated. This study provides a comprehensive CNS transduction map in a useful preclinical large animal model enabling the selection of potentially clinically transferable rAAV serotypes based on disease specificity. Therefore, our data are instrumental for the clinical evaluation of these rAAV vectors in human neurodegenerative diseases.  相似文献   
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