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1.
Hemorrhage following mandibular osteotomies: a report of 21 cases   总被引:1,自引:0,他引:1  
Hemorrhage associated with mandibular osteotomies, especially to the extent that it becomes life threatening, is a rare occurrence and its risk is less than that following maxillary orthognathic surgery. Twenty-one cases of significant bleeding following mandibular sagittal split ramus osteotomies, vertical and oblique ramus osteotomies, and genioplasties are presented. Life-threatening hemorrhage associated with mandibular osteotomies is primarily an intraoperative problem and the incidence of major postoperative and recurrent hemorrhage is not as great as following maxillary osteotomies. Suggestions for the avoidance and treatment of these bleeding complications are discussed.  相似文献   
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Mannan-binding protein (MBP) is a lectin which, upon binding to certain carbohydrates, activates the classical pathway of complement without the involvement of antibody or C1q. Deficiency of the MBP is associated with an opsonic defect and recurrent infections during early life. An amino acid substitution in the exon 1 at codon 54 in the MBP gene (GGC [glycine] to GAC [aspartic acid]) has been shown to be closely associated with low MBP concentration in Caucasoids. The gene frequency of the mutant allele in this population has been estimated at 0.13. In the study described here, we investigated the association between the mutant allele and MBP protein concentration in Eskimos from East-Greenland and black Africans from the Baringo District in Kenya. The frequency of the GAC allele was identical in Eskimos and Caucasoids (0.13). No overlap with regard to MBP concentration between the genotypes was found in the Eskimos. In contrast, the Africans revealed a low frequency of the GAC allele (0.009). However, the median MBP protein concentration was approximately 5 times lower among the Africans than the Eskimos. In 12.6% of the Africans and in 2.5% of the Eskimos, MBP was undetectable. Thus, MBP deficiency is the most frequent immunodeficiency so far described. The high prevalence of MBP deficiency among healthy individuals indicates that MBP deficiency also confers some selective advantages. We advance the hypothesis that MBP deficiency is maintained in populations because MBP deficiency decreases the infectivity of some intracellular micro-organisms which are dependent on opsonization.  相似文献   
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Although adenocarcinoma is a well known complication of chronic inflammatory bowel disease, primary gastrointestinal lymphoma occurring in Crohn's disease is rare. A 40-year-old man with 10 year-history of Crohn's disease had multiple longitudinal ulcerative lesions on descending colon in follow-up colonoscopic examination. Microscopic examination of proximal descending colon revealed peripheral T cell lymphoma and other site of the descending colon was consistent with Crohn's disease. The patient reached complete remission of malignant lymphoma after three cycles of combined chemotherapy. He has been well for 10 months with sulfasalazine maintenance therapy but was admitted to the hospital due to spontaneous bowel perforation of ascending colon. Right hemicolectomy was done, but the patient died of post-surgical recurrent mesenteric abscess and sepsis. To the best of our knowledge, this is the first case of Non-Hodgkin's lymphoma complicating Crohn's disease in Korea which was confirmed by immunohistochemical studies.  相似文献   
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Giant vascular eccrine spiradenoma (GVES) is a rare variant of benign tumors of the sweat glands, which differs from common eccrine spiradenoma in both its size and vascularity. Clinically as well as macroscopically, this intradermal or subcutaneous encapsulated tumor might be mistaken for an angiomatous lesion or thrombosis. Histological examination reveals clearly delimited "cords" showing two types of cells, prominent blood-filled cavities and extensive hemorrhages. According to immunohistochemical findings, the epithelial cells contain cytokeratin, protein S-100 and carcino-embryonal antigen (CEA). Like the endothelial cells of vessels, some of the luminal epithelial cells also bind Ulex europaeus lectin; however, they do not show factor VIII-associated antigen.  相似文献   
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Most (18/21) children with perennial asthma gave dual (immediate and late) responses to bronchial provocation with two of Dermatophagoides pteronyssinus, and either timothy grass pollen or cat fur. Most (19/21) also showed dual responses to skin prick tests, only half (11/21) gave dual responses in the nose, mainly with timothy grass pollen, and these were associated with allergic rhinitis. Only two children gave dual responses in lung, skin and nose to both antigens, and only two gave immediate reactions without late reactions in all positive tests; most showed different patterns of response according to the organ tested or the antigen used for provocation. Our results suggest that local factors may be important in determining the pattern of allergic response in a 'target' organ, and that dual responses are strongly associated with the patient's symptoms.  相似文献   
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The monoclonal antibody Myc 1-6E10 was used to determine the cellular distribution of the c-myc oncogene product p62c-myc in 60 mucinous ovarian tumours. Three patterns of immunostaining were apparent: (i) nuclear staining alone; (ii) staining of the nucleus and basal cytoplasm; and (iii) staining of the entire cell. Of the 21 cases of mucinous cystadenoma, 11 showed nuclear staining alone, and a further case showed additional weak staining of the basal cytoplasm. Nuclear staining alone was not present in any of the 17 borderline mucinous tumours examined. Strong staining of the nucleus and basal cytoplasm was seen in 16 of these borderline cases, six of which also showed focal staining of the apical cytoplasm. All 22 cases of mucinous cystadenocarcinoma showed staining of the cell nucleus and entire cell cytoplasm. Focal staining of the apical cytoplasm in six of 17 borderline mucinous tumours produced a pattern of c-myc immunostaining similar to that of cystadenocarcinoma. Retrospective analysis of the clinical data showed that no significant differences between patients with borderline tumours of these two categories could be defined. Although immunostaining with Myc 1-6E10 can be used in the categorisation of mucinous ovarian tumours, it is concluded that standard histological criteria are more accurate indicators of tumour behaviour than is an assessment of c-myc expression.  相似文献   
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We have recorded the systemic and mammary/mucosal immune responses of women following natural infection with RS virus during the second and third trimesters of pregnancy. Anti-RS virus IgG antibody levels in the sera of women collected in the first trimester of pregnancy showed a bimodal distribution with high and low antibody groups. Antibody levels increased after exposure to the winter RS virus epidemic in the second trimester of pregnancy, probably as a result of infection but only for women in the low antibody group. Despite the increases, antibody levels for these women remained well below those of the high antibody group. There was no rise in mean antibody levels after exposure in the third trimester, even among women with low antibody, suggesting a degree of immunosuppression in late pregnancy. There was no evidence that infection during pregnancy was associated with adverse consequences for the infant. Exposure to RS virus in the first two trimesters, but not the third, was associated with high colostral IgA antibody levels that were maintained in the milk throughout the first 7 weeks of lactation. There was a significant correlation between colostral and maternal nasal IgA antibody levels at delivery. Levels of blood or colostral lymphocyte transformation responses at delivery were unaffected by exposure to RS virus in pregnancy. These observations upon natural infection suggest that vaccination during pregnancy is likely to achieve only marginal effects upon serum antibody levels but boost maternal mammary/mucosal immunity.  相似文献   
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