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81.
The aim of present study was to establish normative data for the distribution of nuchal translucency (NT) thickness in normal Korean fetuses. The data were collected from pregnant women with singleton pregnancies in whom fetal ultrasound was performed and the fetal NT thickness was measured between 11 and 14 weeks of gestation. Among them, a total of 2,577 fetuses with a known normal outcome were included in this study. The distribution of multiple of median (MoM) values of the NT thickness with crown-rump length (CRL) in 10-mm intervals and the 95th percentile of MoM were calculated with the linear regression method. The present study showed that NT measurements increase with increasing CRL and a false positive rate increases with increasing gestational age. Therefore, a fixed cut-off point through the first trimester was not appropriate and each NT measurement should be examined according to the gestational age. The present study offers normative data of the fetal NT thickness in a Korean population, which can be used as reference for screening chromosomal aberrations or other congenital abnormalities in the first trimester.  相似文献   
82.
A monoclonal antibody (MAbIII604) specific to phenolic glycolipid Tb (PGL-Tb), a Mycobacterium tuberculosis-specific antigen, was produced and used in the detection of the antigen. MAbIII604 reacted with the PGL-Tb antigen but not with other phenolic glycolipids from Mycobacterium leprae, M. bovis, and M. kansasii, thus indicating the specificity of the monoclonal antibody to PGL-Tb. A dot enzyme-linked immunosorbent assay with MAbIII604 was employed to detect the PGL-Tb antigen in lipids purified from M. tuberculosis clinical isolates. Of 50 isolates, 32 (64.0%) showed clear evidence of the PGL-Tb antigen by the dot enzyme-linked immunosorbent assay, but there were marked variations in the intensities and sizes of spots. This suggests differences in PGL-Tb antigen production among M. tuberculosis strains even when they are grown in the same culture media and conditions. This was most evident from the fact that in only eight (16.0%) of the isolates examined was the PGL-Tb antigen detectable by thin-layer chromatography, which is much less sensitive for the detection of glycolipid antigens. This study shows that monoclonal antibodies specific to PGL-Tb are useful in detecting the antigen in lipid extracts and that there is a marked variation in the PGL-Tb production among M. tuberculosis clinical isolates.  相似文献   
83.
Following horseradish peroxidase (HRP) injection into the cephalopharyngeal muscle (CeP), the hyopharyngeal muscle (HP), the thyropharyngeal muscle (TP), the cricopharyngeal muscle (CP) and the cervical esophagus muscle (CE) of the cat, labeled neurons were identified in the nucleus retrofacialis and the rostral part of the nucleus ambiguus ipsilaterally. The rostral end of the labeled cell column was located more rostrally for CeP and HP than for TP, CP and CE. No difference was noted within the former two or within the latter three. The level of the caudal end of the labeled cell column became more caudal in the order of CeP, HP, TP and CP. The caudal end was located more rostral for CE than for TP. The neurons for CE were located more ventro-laterally than those for the other muscles.  相似文献   
84.
Pulmonary dysfunction is a significant complication following allogeneic hematopoietic stem cell transplantation (HSCT), and is associated with significant morbidity and mortality. Effective antimicrobial prophylaxis and treatment strategies have increased the incidence of noninfectious lung injury, which can occur in the early posttransplant period or in the months and years that follow. Late-onset noninfectious pulmonary complications are frequently encountered, but diagnostic criteria and terminology for these disorders can be confusing and therapeutic approaches are suboptimal. As a consequence, inaccurate diagnosis of these conditions may hamper the appropriate data collection, enrollment into clinical trials, and appropriate patient care. The purpose of this review is to clarify the pathogenesis and diagnostic criteria of representative conditions, such as bronchiolitis obliterans syndrome and bronchiolitis obliterans organizing pneumonia, and to discuss the appropriate diagnostic strategies and treatment options.  相似文献   
85.
The etiology of systemic lupus erythematosus (SLE) is very complex, and genetic factors appear to play a significant role in susceptibility to SLE, in determining the disease expression, and in the autoantibody profiles of individuals with SLE. DNA methyltransferase-1 (DNMT1) is a major enzyme that determines genomic methylation patterns and both maintains methyltransferase and exhibits de novo DNA methylation activity in vivo. In order to clarify the association of DNMT1 polymorphisms with SLE, we scrutinized the genetic polymorphisms in exons and their boundaries of DNMT1, including the –1,500 bp promoter region, by direct sequencing in 24 Korean individuals. Twenty-nine sequence variants were identified: two in 5UTR, six in exons, and 21 in introns. Eight of these polymorphisms were selected for a larger-scale genotyping (n=680) by considering their allele frequencies, haplotype-tagging status, and linkage disequilibrium coefficiencies (LDs) among polymorphisms. The associations between DNMT1 polymorphisms and the clinical profiles of SLE were analyzed. No significant associations with the risk of SLE were detected. However, further analyses of association with autoantibody production among SLE patients revealed that one nonsynonymous SNP, +14463G>C (V120L) in exon 4, was weakly associated with an increased risk of anti-La antibody production (P=0.04), although the significance could not be retained after correction of multiple tests. The DNMT1 variations and haplotypes clarified in this study would provide valuable information for future genetic studies of other autoimmune diseases.  相似文献   
86.
The presence of lactose-fermenting Salmonella strains in clinical case materials presented to microbiology laboratories presents problems in detection and identification. Failure to detect these strains also presents a public health problem. The laboratory methods used in detecting lactose-fermenting Salmonella enterica serotype Typhimurium from six outbreaks of salmonellosis in veal calves are described. Each outbreak was caused by a multiply-resistant and lactose-fermenting strain of S. enterica serotype Typhimurium. The use of Levine eosin-methylene blue agar in combination with screening of suspect colonies for C8 esterase enzyme and inoculation of colonies into sulfide-indole-motility medium for hydrogen sulfide production was particularly effective for their detection. A hypothesis for the creation of lactose-fermenting salmonellae in the environment is presented. It is proposed that the environment and husbandry practices of veal-raising barns provide a unique niche in which lactose-fermenting salmonellae may arise.  相似文献   
87.
In order to develop a structured and objective diagnostic instrument, authors completed: (1) the translation and back translation of the Korean version of the Kiddie-Schedule for Affective Disorders and Schizophrenia - Present and Lifetime Version (K-SADS-PL) and (2) the examination of its validity and reliability of the K-SADS-PL-Korean version (K-SADS- PL) when used with Korean children. A total of 91 study subjects were recruited from child and adolescent psychiatry outpatient clinics. Clinical diagnoses were used as a gold standard for the examination of validity of K-SADS-PL-K. Consensual validity of threshold and sub-threshold diagnoses were good to excellent for attention-deficit/hyperactivity disorder (ADHD), fair for tic and oppositional defiant disorders, and poor to fair for anxiety and depressive disorders. Inter-rater and test-retest reliabilities were fair to excellent for ADHD and tic disorder. The significant correlations between the K-SADS-PL-K and Korean Child Behavior Checklist (K-CBCL) were found, which provided additional support for the concurrent validity of the K-SADS-PL-K. Sensitivities varied according to the diagnostic categories, but specificities remained high over all diagnoses, suggesting that the K-SADS-PL-K is a desirable confirmatory diagnostic tool. The results of this study suggest that the K-SADS-PL-K is an effective instrument for diagnosing major child psychiatric disorders, including ADHD, behavioral disorders and tic disorders in Korean children. Future studies will examine the validity and reliability of the K-SADS-PL-K in larger samples, including adolescents and community samples on a variety of child and adolescent psychiatric disorders.  相似文献   
88.
OBJECTIVE: Inhaled corticosteroids play a pivotal role in the treatment of asthma. To observe the mechanisms of glucocorticoids, we focused our study on the comparison of several glucocorticoids' effects on eotaxin expression in the airway epithelial cells. METHODS: Airway epithelial cell line BEAS-2B was cultured in vitro. Cells were preincubated with or without glucocorticoids (becromethasone dipropionate; BDP, budesonide; BUD, fluticasone propionate; FP) and stimulated with TNFalpha and/or IL-4. Protein levels of eotaxin in the supernatants of the cultured cells were determined by ELISA. RESULTS AND CONCLUSIONS: TNFalpha and IL-4 increased the levels of eotaxin in BEAS-2B cells. Combination of these cytokines synergistically upregulated the eotaxin expression as reported previously. Each glucocorticoid significantly inhibited the expression of eotaxin protein induced with TNFalpha and IL-4 and the compared efficacy was in order of FP>BUD>BDP. FP seemed most potent and the inhibitory effect was also observed with relatively low concentration such as 10 (-10)M. Taken together, the comparison of the potency of each glucocorticoid using airway epithelial cells may reflect the efficacy of these drugs in asthmatics.  相似文献   
89.
Phosphoglycerate kinase (PGK) is an enzyme that produces one ATP molecule in the glycolytic pathway. Clonorchis sinensis is largely dependent on glycolysis for energy production. We performed immunoelectron microscopy on adult C. sinensis by using mouse immune serum raised against recombinant C. sinensis PGK. A high density of gold particles was found in the microvilli of the intestinal epithelium and in lamellae of the sperm duct. PGK was common in the somatic cells of intra-uterine eggs and in excreted products. It was localized with moderate intensity in muscular fibers of the subtegumental muscle layer, and in the myoepithelia of the intestine and excretory bladder. We suggest that PGK plays an essential role in C. sinensis energy production for movement via muscle contraction.  相似文献   
90.
Otitis media with effusion (OME) is one of the most common ear diseases. Bacterial endotoxins and several inflammatory cytokines appear to be involved in the pathogenesis of OME in children; however, little is known of the immunological aspects of the onset of OME in adults. We sought to determine the presence of macrophage migration inhibitory factor (MIF) as well as interleukin 1beta (IL-1beta), tumor necrosis factor alpha (TNF-alpha), RANTES (regulated upon activation, normal T-cell expressed and presumably secreted), and endotoxin in middle ear effusions (MEEs) from adult patients with OME. In addition, the levels of MIF in MEEs from adults and children were compared. MEE was obtained from 95 adults and 11 children. The levels of MIF, IL-1beta, TNF-alpha, and RANTES were determined by enzyme-linked immunosorbent assay, and the concentrations of endotoxin and total protein were determined by the Endospec assay and bicinchoninic acid assay, respectively. MIF was detected in 97.9% of the MEEs from adults, while endotoxin, IL-1beta, TNF-alpha, and RANTES were detected in 96.8, 12.6, 5.3, and 43.9%, respectively. In addition, the level of MIF was significantly higher than those of endotoxin, IL-1beta, and TNF-alpha. A positive correlation between the levels of MIF and endotoxin was observed. MIF and endotoxin were detected in 81.8 and 72.7%, respectively, of the MEEs from the children. The level of MIF was significantly higher in the children, and conversely that of endotoxin was significantly higher in the adults. These results suggest that the interaction between MIF and endotoxin may promote fluid collection in the middle ear, particularly in adults.  相似文献   
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