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71.

Background  

Few epidemiologic studies have assessed health-related quality of life (HRQL) of asthma patients from a general population and it is unclear which instrument is best suitable for this purpose. We investigated the validity of the Asthma Quality of Life Questionnaire (AQLQ) and the SF-36 completed by individuals with asthma from the population-based SAPALDIA (Swiss study on air pollution and lung diseases in adults) cohort.  相似文献   
72.
73.
A total of 76 T-cell clones established from peripheral blood (PB) of 2 patients with the acquired immune deficiency syndrome (AIDS) and of 141 T-cell clones established from PB of 3 normal donors were compared for their ability to produce interleukin 2 (IL-2) and gamma-interferon (gamma-IFN). Twenty-seven clones from AIDS patients and 85 clones from controls expressed the CD4 phenotype, whereas 49 clones from AIDS patients and 56 clones from controls expressed the CD8 phenotype. There were no significant differences in the proportions of IL-2-producing CD4 T-cell clones established from PB of patients with AIDS and controls, but the mean concentration of IL-2 produced by CD4 clones from AIDS patients was significantly lower than that produced by CD4 clones from controls. Both the proportion of gamma-IFN-producing CD4 clones and the mean concentration of gamma-IFN produced by CD4 clones were significantly lower in AIDS patients than in controls. In contrast, there were no differences between AIDS patients and normal individuals in the proportion of IL-2- or gamma-IFN-producing CD8 clones, or in the mean concentration of IL-2 and gamma-IFN produced by CD8 clones. These data suggest that the reduced ability of PB T-cells from patients with AIDS to produce IL-2 and gamma-IFN is not simply due to altered proportions or numbers of T-cell subpopulations, but also reflects intrinsic abnormalities of individual CD4 T lymphocytes.  相似文献   
74.
BACKGROUND: Cardiac output can be determined by using a variety of methods. OBJECTIVES: To determine the precision and bias between 3 methods for determining cardiac output: bioimpedance, thermodilution, and the Fick method. METHODS: Cardiac output was determined by using bioimpedance via neck and thorax patches and thermodilution via pulmonary artery catheter in 46 patients in the intensive care unit. A subset of 15 patients also had cardiac output determined by using the Fick method. RESULTS: Mean (SD) cardiac output in all patients was 6.3 (2.2) L/min by thermodilution and 5.6 (2.0) L/min by bioimpedance. In the 15 patients in whom all 3 methods were used, mean cardiac output was 6.0 (1.7) L/min by thermodilution, 5.3 (1.7) L/min by bioimpedance, and 8.6 (4.5) L/min by the Fick method. Bias and precision (mean difference +/- 2 SDs) were 0.7 +/- 2.9 L/min between thermodilution and bioimpedance, 1.7 +/- 3.8 L/min between the Fick method and thermodilution, and 2.4 +/- 4.7 L/min between the Fick method and bioimpedance. CONCLUSION: Bioimpedance, thermodilution, and Fick determinations of cardiac outputs are not interchangeable in a heterogeneous population of critically ill patients.  相似文献   
75.
The aim of this study is to investigate the effects of formalin fixation on the degradation of DNA molecules in five different healthy tissues exempted during the autopsy, as well as the selection of the method that is most suitable for the DNA isolation. Heart muscle, liver, brain, lung and kidney tissue obtained from the healthy people who suddenly died from a violent death were used. The parts of tissue were fixed in 10% phosphate-buffered formalin as well as in 4% unbuffered formalin at room temperature. Morphology of tissue was studied using H&E staining. The DNA was isolated 6?h, 1–7 days (every 24?h), 10, 14, 28 days and 2 months after fixation using two different methods: extraction with phenol-chloroform-isoamyl alcohol as well as with PureLink Genomic DNA Kit. Yield and purity of the DNA samples were measured spectrophotometrically at 260?nm and 280?nm. The PCR amplifications of the glycerol-3-phosphate dehydrogenase 1 (GPD1, 150 bp), ß actin (ACTB, 262 bp) and ribosomal protein L4 (RPL4, 407 bp) genes were performed to evaluate the degree of DNA fragmentation. The RPL4 gene was amplified up to 72?h, ACTB gene up to 14 days and GPD1 gene up to 28 days from tissue fixed in phosphate-buffered formalin using phenol-chloroform-isoamylalcohol protocol for DNA isolation. Liver and kidney gave better results of PCR amplification, but statistical significance between tissues was not found. Preserving period, fixative and DNA extracting method are important factors for successful PCR amplification. The healthy tissue, fixed in phosphate-formalin up to 28 days, can be useful source in molecular studies. Tissues fixed in unbuffered formalin are suitable for molecular analysis up to 7 days.  相似文献   
76.
We studied the clinical correlations and epitopes of autoantibodies directed to a novel autoantigen, Bicaudal D (BICD2), in systemic sclerosis (SSc) and reviewed its relationship to centromere protein A (CENP-A). 451 SSc sera were tested for anti-BICD2 using a paramagnetic bead immunoassay and then univariate and multivariate logistic regression was used to study the association between anti-BICD2 and demographic and clinical parameters as well as other SSc-related autoantibodies. Epitope mapping was performed on solid phase matrices. 25.7% (116/451) SSc sera were anti-BICD2 positive, of which 19.0% had single specificity anti-BICD2 and 81.0% had other autoantibodies, notably anti-CENP (83/94; 88.3%). Compared to anti-BICD2 negative subjects (335/451), single specificity anti-BICD2 subjects were more likely to have an inflammatory myopathy (IM; 31.8% vs. 9.6%, p = .004) and interstitial lung disease (ILD; 52.4% vs. 29.0%, p = .024). Epitope mapping revealed a serine- and proline-rich nonapeptide SPSPGSSLP comprising amino acids 606–614 of BICD2, shared with CENP-A but not CENP-B. We observed that autoantibodies to BICD2 represent a new biomarker as they were detected in patients without other SSc-specific autoantibodies and were the second most common autoantibody identified in this SSc cohort. Our data indicate that the major cross-reactive epitope is associated with anti-CENP-A but, unlike anti-CENP, single specificity anti-BICD2 antibodies associate with ILD and IM.  相似文献   
77.
78.
OBJECTIVE: To look for a quantitative model linking departmental consumption of antibiotic drugs to the subsequent isolation of resistant hospital-acquired coliform pathogens. MATERIALS AND METHODS: Included in the study were all patients with hospital-acquired bloodstream infections caused by a coliform pathogen, detected in six departments of internal medicine of one university hospital during the period 1991-1996, who had not been hospitalized in the month before the infection (n = 394). Departmental consumption of antibiotics in the year before the infection [expressed as defined daily dosages (DDD)/100 patient days], antibiotic treatment given to the individual patient before the infection, the day of hospital stay on which the infection occurred, and the department and the calendar year were all included in a logistic model to predict the isolation of a resistant pathogen. We looked at five drugs: gentamicin, amikacin, cefuroxime, ceftazidime and ciprofloxacin. RESULTS: Five logistic models were fitted for the resistance to each of the antibiotic drugs. The multivariable-adjusted odds ratios for a pathogen resistant to the specific antibiotic were 1.03 [95% confidence interval (CI) 0.70-1.50] for gentamicin, 1.80 (95% CI 1.00-3.24) for amikacin, 1.12 (95% CI 1.02-1.23) for cefuroxime, 1.45 (95% CI 1.19-1.76) for ceftazidime and 1.06 (95% CI 0.57-1.97) for ciprofloxacin, per 1 DDD/100 patient days. CONCLUSIONS: The departmental consumption of cephalosporin drugs and amikacin in six autonomous departments of medicine in the same hospital was associated with a measurable and statistically significant increase in the probability of infection caused by a resistant pathogen.  相似文献   
79.
The aim of this study was to investigate the morphology, molecular phenotypes, distribution and developmental history of interstitial neurons in the human corpus callosum, here defined as intracallosal neurons. We analysed 26 fetuses, three newborns, five infants and children, and eight adults [age range – 15 weeks postconception (PCW) to 59 years] by means of acetylcholinesterase (AChE) histochemistry and immunohistochemistry for neuron markers (MAP2, NeuN, NPY, calretinin and calbindin). We found a heterogeneous neuron population, positioned within the callosal trunk itself (aside from neurons present in the transient midline structures such as callosal sling, septa or subcallosal zone), which was most numerous during the second half of gestation and early postnatal years. We named these cells intracallosal neurons. At 15 PCW, the intracallosal neuron population consisted of poorly differentiated, small fusiform or bipolar, migratory‐like MAP2‐ or calretinin‐positive neurons which could be observed until mid‐gestation. Later the population comprised morphologically diverse, predominantly well‐differentiated MAP2‐, NPY‐, calbindin‐ and AChE‐positive neurons. The morphological differentiation of intracallosal neurons culminated in the newborns and remained pronounced in infants and children. In the adult brain, the intracallosal neurons were found only sporadically, with small somata and poorly stained dendrites. Thus, intracallosal neurons form part of a transitory neuron population with a developmental peak contemporaneous to the critical period of callosal formation. Therefore, they may be involved in processes such as axon guiding or elongation, withdrawal of exuberant axons, fasciculation, or functional tuning, which occur at that time.  相似文献   
80.

Summary

Thyroid C cells hormone, calcitonine, inhibits bone resorption. We have demonstrated that daidzein treatment of orchidectomized rats (model for osteoporosis) stimulated C cells and increased trabecular bone mass. These results suggest that, besides direct action, daidzein may also affect bone structure indirectly through enhancement of thyroid C cell activity.

Introduction

Thyroid C cells produce calcitonin (CT) which acts as an inhibitor of bone resorption. In this study, the influence of daidzein treatment on thyroid C cells, bone structure, and bone function in orchidectomized (Orx) middle-aged rats was investigated.

Methods

Sixteen-month-old Wistar rats were divided into Orx and sham-operated (SO) groups. Half the Orx rats were given subcutaneous injections of daidzein (30 mg/kg b.w./day) for 3 weeks. CT-immunopositive thyroid C cells were morphometrically analyzed. The metaphyseal region of the proximal tibia was measured histomorphometrically, and cancellous bone area (B.Ar), trabecular thickness (Tb.Th), trabecular number (Tb.N), and trabecular separation (Tb.Sp) were calculated. Serum samples were analyzed for CT and osteocalcin (OC), calcium (Ca) and phosphorus concentrations, and urine samples for Ca levels.

Results

Treatment of Orx animals with daidzein significantly increased volume of C cells compared to the Orx rats. Daidzein also enhanced B.Ar, Tb.Th, and Tb.N and reduced Tb.Sp. The serum OC and urinary Ca concentrations decreased significantly in comparison with the Orx group.

Conclusions

These findings indicate that daidzein treatment stimulates thyroid C cells, increase trabecular bone mass, and decrease bone turnover in Orx middle-aged rats, which is the model of male osteoporosis.  相似文献   
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