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71.
Autoimmune cholangitis is a clinical constellation of chronic cholestasis, histological changes of chronic nonsuppurative cholangitis and the presence of autoantibodies other than antimitochondrial antibody (AMA). It is uncertain whether this entity is definitely different from AMA positive primary biliary cirrhosis (PBC), though it shows some differences. We report a case of autoimmune cholangitis in a 59-year-old woman, who had been previously diagnosed as AMA-positive PBC associated with rheumatoid arthritis, has been converted to an AMA-negative and anticentromere antibody-positive PBC during follow-up. The response to ursodeoxycholic acid treatment is poor except within the first few months, but prednisolone was dropping the biochemical laboratory data.  相似文献   
72.
The HLA-B51 allele is known to be associated with Behcet's disease (BD) in many ethnic group. However, it has not yet been clarified whether the HLA-B51 gene itself is the pathogenic gene related to BD or whether it is some other gene in linkage disequlibrium with HLA-B51. Recently, the Triplet repeat (GCT/AGC) polymorphism in transmembrane region of the MHC class I chain-related A (MICA) gene was identified. To investigate the association of MICA with BD, we studied the MICA polymorphism in 108 Korean BD patients and 204 healthy controls in relation to the presence of HLA-B51 and clinical manifestations. The triplet repeat polymorphism was determined by polymerase chain reaction (PCR)-denaturing polyacrylamide gel electrophoresis (PAGE). The phenotype frequency of the MICA*A6 allele (relative risk, RR=2.15, p=0.002) and HLA-B51(RR=1.87, p=0.022) were significantly increased in the Korean patients with BD. A strong linkage disequilibrium was observed between the MICA*A6 and HLA-B51 in both the patients with BD and control subjects. Stratification analysis showed that MICA*A6 homozygosity was strongly associated with BD in the HLA-B51-negative population, and HLA-B51 was also associated with MICA*A6-negative population. In conclusion, MICA*A6 rather than HLA-B51 was strongly associated with Korean patients with BD, and the MICA*A6 allele is a useful susceptibility marker of BD, especially in the HLA-B5-negative  相似文献   
73.
The synthesis, intracellular translocation, and secretion of mannose-containing glycoproteins(s) by periodontal ligament fibroblasts have been investigated by means of electron microscopic radioautography. Tritiated mannose was administered to young mice via jugular vein, and radioautographs were prepared at 5, 10, 20, and 35 minutes, 4 and 8 hours after injection. Analysis of electron microscopic radioautographs revealed a maximum labeling (94%) with 3H-mannose of the rough endoplasmic reticulum at 5 minutes. Labeling of the Golgi components started to increase from 10 minutes (14%) and reached a maximum level at 20 minutes (31.2%). At 35 minutes, secretion granules, dense bodies, profiles of intracellular collagen, and the cell surface were labeled. At 8 hours, most labelling (79.2%) was extracellular, and associated either with the collagenous matrix (43.7%) or the cell surface (35.5%). Cytoplasmic vesicles containing dense materials around collagen fibrils were also labeled at 8 hours. It is concluded that mannose is directly incorporated into the rough endoplasmic reticulum (RER), and that mannose-containing glycoprotein(s) are packaged in the Golgi apparatus into secretory granules. Mannose-containing glycoprotein(s) become distributed on the periodontal ligament (PDL) fibroblast cell surface, cytoplasmic dense bodies, and the extracellular matrix.  相似文献   
74.
p53 codon 72 polymorphism and risk of cervical carcinoma in Korean women   总被引:3,自引:0,他引:3  
A common polymorphism of the wild type p53 is known at codon 72 of exon 4, with 2 alleles encoding either arginine (CGC, p53Arg) or proline (CCC, p53Pro). A recent study suggested that this polymorphism affects the susceptibility of p53 protein to human papillomavirus E6 oncoprotein mediated degradation and that individuals homozygous for p53Arg are seven times more susceptible to HPV-associated carcinogenesis of the cervix than heterozygotes. To examine whether the p53Arg genotype could be a risk factor for HPV-associated cervical carcinomas in the Korean population, we analyzed the p53 codon 72 polymorphism status of HPV-positive invasive cervical carcinomas from 52 Korean women and 103 healthy control samples. The proportion of individuals homozygous for p53Arg, homozygous for p53Pro, and heterozygous for the two alleles were 40%, 19%, and 41% in normal healthy controls; 42%, 17%, and 40% in women with HPV-positive invasive cervical carcinoma. There were no significant differences in the distribution of p53 genotypes between controls and cervical carcinomas. This finding indicates that the p53Arg genotype is not associated with an increased susceptibility to cervical carcinoma in Korean women.  相似文献   
75.
We recently treated two cases of chronic pancreatitis with obstructive jaundice due to compression of the common bile duct by pancreatic pseudocyst. The two cases were males admitted with the complaint of icteric skin color. The first, a 46-year-old male, admitted with the complaint of icteric skin color. He was treated by operative cystojejunostomy after percutaneous drainage of the pseudocyst and percutaneous transhepatic biliary drainage. The other case was a 58 year-old male who admitted with the complaint of icteric skin color. He had an infected pseudocyst in the pancreas and was endoscopically treated. Both of them were discharged with favorable clinical course and normal laboratory findings after the treatment. The former patient remained well 11 months after treatment, but the latter patient died from necrotizing pancreatitis and septic shock 6 months after treatment. Most cases of obstructive jaundice associated with pseudocysts appear to be due to fibrotic stricture of the intrapancreatic portion of the common bile duct rather than due to compression of the bile duct by the pseudocyst. In a patient with secondary pancreatic infection or obstructive jaundice following pancreatic disease, differentiating between these two conditions is an important aspect of accurate diagnosis and therapy. Herein we report two unusual cases of chronic pancreatitis with pseudocyst complicated by obstructive jaundice.  相似文献   
76.
Chung Y  Cho J  Chang YS  Cho SH  Kang CY 《Immunobiology》2002,206(4):408-423
Allergic asthma is an inflammatory disease of the airways, and Th2 cells secreting IL-4 and IL-5 play a pivotal role in its pathogenesis. We have previously demonstrated that oral tolerance can be induced and maintained more profoundly in a Th2-related immune response, and that an ongoing immune response can be suppressed by the oral administration of antigen combined with an appropriate feeding regimen. In the present study, we examined the preventive and therapeutic effects of the oral administration of allergen on a Th2-mediated immune disorder using a murine model of asthma. Our results show that the development of asthma can be blocked completely by orally administering allergen. Airway hyperreactivity, allergen-specific IgE production, Th2-derived cytokines, allergen-induced T cell proliferation and the infiltration of inflammatory effector cells into the lung were prevented by such oral administration. To assess the therapeutic effects of oral administration on the progression of asthma, we tested the effects of oral tolerance in an established asthma model, and found that a multiple high dose-feeding regimen was effective at suppressing the progression of mild asthma. In the high dose-feeding group, the number of eosinophils in bronchoalveolar lavage fluid was reduced and airway reactivity also decreased. However, this was insufficient to reduce airway reactivity and eosinophilia in bronchoalveolar lavage fluid in cases of severe asthma. These results demonstrate that allergic asthma may be ameliorated by feeding allergen; there is hope that these results will provide a new immunotherapeutic strategy for allergic asthma.  相似文献   
77.
Previous molecular genetic studies of laryngeal squamous cell carcinoma (SCC)have shown certain chromosomal regions with recurring alterations. But studies of sequential molecular alterations and genetic progression model of laryngeal SCC have not been clearly defined. To identify the chromosomal alterations associated with the carcinogenesis of laryngeal SCC, we analyzed genomic DNA from microdissected squamous metaplasia, squamous dysplasia, invasive SCC, and metastatic carcinoma samples from 22 laryngeal SCC patients for loss of heterozygosity (LOH) at microsatellite loci. Ten microsatellite markers on chromosome 3p, 8p, 9p, and 17p were used. LOH at 9p21 was observed in the all stages including squamous metaplasia, squamous dysplasia, invasive SCC and metastatic carcinoma. LOH at 17p13.1, 3p25 and 3p14.2 was observed from the squamous dysplasia, invasive SCC and metastatic carcinoma. LOH at 8p21.3-p22 was observed mainly from the invasive SCC and metastatic carcinoma. The results suggest that 9p21 in the early event, 17p13.1, 3p25 and 3p14.2 in the intermediate event and 8p21.3- p22 in the late event may be involved in the laryngeal carcinogenesis.  相似文献   
78.
We examined the structural requirements within the species-specific 3,6-di-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-2,3-di-O-methyl- alpha-L-rhamnopyranosyl-(1 leads to 2)-3-O-methyl-alpha-L-rhamnopyranose unit of the phenolic glycolipid I antigen of Mycobacterium leprae for binding to anti-glycolipid immunoglobulin M from human leprosy sera. We used chemically defined, partially deglycosylated fragments of phenolic glycolipid I, two other minor M. leprae-specific phenolic glycolipids (those containing 6-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-2,3-di-O-methyl-alpha- L-rhamnopyranosyl-(1 leads to 2)-3-O-methyl-alpha-L-rhamnopyranose and 3,6-di-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-3-O-methyl-alpha- L-rhamnopyranosyl-(1 leads to 2)-3-O-methyl-alpha-rhamnopyranose units), and phenolic glycolipids from other mycobacteria. Additionally, the trisaccharide of phenolic glycolipid I, the 3,6-di-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-2, 3-di-O-methyl-alpha-L-rhamnopyranose, the 6-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-2,3-di-O-methyl-alpha- L-rhamnopyranose, and the beta-D-glucopyranosyl-(1 leads to 4)-2,3-di-O-methyl-alpha- L-rhamnopyranose disaccharides were synthesized and characterized, and their activities were examined. Only the phenolic glycolipids containing 3,6-di-O-methyl-beta-D-glucopyranosyl at the nonreducing terminus were efficient in binding the anti-glycolipid immunoglobulin M, and the 3,6-di-O-methyl-beta-D-glucopyranosyl-containing di- and trisaccharides were the most effective in inhibiting this binding. Thus, the 3,6-di-O-methyl-beta-D-glucopyranosyl substituent was recognized as the primary antigen determinant in phenolic glycolipid I. With this information, bovine serum albumin containing reductively aminated 3,6-di-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-2,3-di-O-methyl- L-rhamnose was prepared and shown to be highly active in the serodiagnosis of leprosy.  相似文献   
79.
80.
Brain tumors in infants present special diagnostic and therapeutic challenges. To figure out the clinical features, pathological classification of the tumors and the treatment outcome of infantile brain tumors, 458 children (age<16) with brain tumors were reviewed retrospectively. Among them 21 cases (4.6%) were diagnosed during the first 12 months of life. Two tumors were definitely of congenital origin. The majority of infants with brain tumors presented with increased intracranial pressure. Fourteen tumors were located at the supratentorial area. Sixteen cases had neuroepithelial tumors; astrocytoma (optic pathway), supratentorial primitive neuroectodermal tumor (PNET) and medulloblastoma were found in three cases each. There were two treatment-related mortalities. Compared with the outcomes in older children, the treatment outcome was poorer in medulloblastoma and the optic pathway glioma which showed a higher growth potential. Because of the limited application of postoperative adjuvant therapy, radical surgical removal played a more important role in this age group. The prognosis of patients in whom the tumors could not be totally removed, largely depended on the pathological malignancy of the tumors. Though the treatment outcome was not always dismal, immaturity of the brain, higher growth potential, perioperative risks, limitations in adjuvant therapy, and pessimistic attitude on the part of parents made management more challenging.  相似文献   
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