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531.
Oral tolerance to protein antigens   总被引:2,自引:0,他引:2  
Oral tolerance is an active non-response to antigens delivered via the oral route. Mechanisms governing tolerance induction have been well characterized in mouse. Similar studies in man are lacking, although there is evidence that tolerance can be induced. In disease states, tolerance is altered and this may account for the presence of mucosal inflammation. In food hypersensitivity there is evidence that allergens may be handled differently and this may play a role in disease expression.  相似文献   
532.
OBJECTIVE: The purpose of this study was to evaluate the clinical usefulness of a fetal anatomic survey on follow-up antepartum sonograms. METHODS: A retrospective follow-up study was conducted at a low-risk maternity clinic from July 1, 2005, to June 30, 2006. Eligible women had at least 1 prior sonographic examination beyond 18 weeks' gestation with a complete and normal fetal anatomic assessment and at least 1 follow-up sonogram. Full fetal anatomic surveys were performed on all follow-up sonograms regardless of the indication. Neonatal charts were reviewed for those patients whose follow-up sonograms revealed unanticipated fetal anomalies. Neonatal intervention was defined as surgical or medical therapy or arranged subspecialty follow-up specifically for the suspected fetal anomaly. RESULTS: Of a total of 4269 sonographic examinations performed, 437 (10.2%) were follow-up studies. Of these, 101 (23.1%) were excluded because the initial sonogram revealed a suspected fetal anomaly, and 42 (9.8%) were excluded for other reasons. Of the remaining 294 women, 21 (7.1%) had an unanticipated fetal anomaly, most often renal pyelectasis. Compared with follow-up sonography for other reasons, repeated sonography for fetal growth evaluation yielded a higher incidence of unexpected fetal anomalies: 15 (12.3%) of 122 versus 6 (3.5%) of 172 (P = .01). When compared with the neonates in the nongrowth indications group, those neonates whose mothers had sonographic examinations for fetal growth had a higher rate of neonatal interventions: 6 (40.0%) of 15 versus 0 (0%) of 6 (P = .04). CONCLUSIONS: A fetal anatomic survey on follow-up sonograms may identify unanticipated fetal anomalies, especially when the indication is for fetal growth.  相似文献   
533.
A fibrous hamartoma of infancy presented in a 4-month-old girl as three separate masses on her right hand. Magnetic resonance imaging showed that the lesions had indistinct margins, and were infiltrating to the overlying subcuticular layer; there was pathological contrast enhancement and high signal intensity in the bony medulla. The masses were successfully excised. The radiological and physical appearance of fibrous hamartomas in a child may suggest malignancy, but the lesion is typically benign and treatment by local excision is usually successful.  相似文献   
534.
Guiding the decision to transfuse can improve transfusion practices. Effective processes must first identify problem(s) in transfusion practice and then include the attending physician as an educational target. Process improvements that have been shown to be effective include the following: (1) briefly meeting one-on-one with physicians, (2) teaching at scheduled conferences, (3) making daily clinical rounds of patients who receive transfusion, (4) concurrently reviewing orders for transfusion before issue of the blood product, and (5) installing algorithms and guidelines in the operating room. Transfusion practices improved with these process improvements.  相似文献   
535.
Opinions on occlusion and its link to oral health could not be more diverse. These opinions are used as justification for an equally diverse range of treatments for so-called occlusally related problems, from heavy wear to chronic orofacial pain. Many claim to have evidence to back up their opinions, although much of it appears to be from a very weak source or based on clinical experience. The strongest case appears to be made by those who believe there is no link, by virtue of a lack of evidence to support its existence. Yet for many clinicians, it is a self-evident truth that occlusion must be related in some way to the function and dysfunction of the stomatognathic system. This article uses historical research to highlight where the pro-occlusionists may be going wrong. It also offers a new concept, based on anthropological studies, that indicates occlusion's link to oral health, and explains why most patients appear to have no occlusal problems for most of the time. This theory needs to be tested by researchers to establish its validity. In the meantime, dentists who feel the need to treat occlusal problems will find it supports a very conservative approach to care.  相似文献   
536.
Necrotizing fasciitis (NF) is a life-threatening condition, consisting of a soft-tissue infection with rapidly progressive, widespread fascial necrosis. NF may be caused by a wide variety of microbes. Indeed, NF may be an infection of one species of bacteria or may be polymicrobial. Prompt diagnosis and treatment are essential. Surgical debridement and antibiotic therapy are the primary treatment options.  相似文献   
537.
We herein report a 39-year-old woman presented with annular plaque with central clearing on the back, extremities, and breasts. The lesions had raised, firm erythematous borders included a trailing scale. On histologic examination, a perivascular inflammatory cell infiltrate composed of neutrophils and mononuclear inflammatory cells in the upper dermis was shown. We consider our case to represent idiopathic figurate erythema with a dominant infiltration of neutrophils.  相似文献   
538.
The Netherlands is a low endemic country for hepatitis B virus (HBV). Rotterdam, a city in The Netherlands harbors a large group of chronic hepatitis B (CHB) patients of which most are born abroad. The study included 464 consecutive CHB patients who were reported to the Municipal Public Health Service in Rotterdam from January 1, 2002 to September 15, 2005. The HBV genotypes, possible transmission routes of infection and travel history of CHB patients born in The Netherlands, were compared with those CHB patients living in The Netherlands but who were foreign-born, taking into account the ethnicity of the mother. Of the 464 patients with CHB infection, 14% were Dutch-born and 86% were foreign-born. The CHB patients in the Dutch-born group had genotypes A (35%), B (15%), C (11%), D (37%), and G (2%). In the foreign-born group, the distribution of genotypes was A (20%), B (15%), C (11%), D (40%), and E (15%). In the Dutch-born group, sexual transmission accounted for a larger proportion of infections (P < 0.0001) compared to the foreign-born group, whereas perinatal transmission is reported to be higher in the foreign-born group and in the Dutch-born group with a foreign mother. The genotypes of the chronic HBV strains determined corresponded well with the HBV genotypes expected from the countries of origin of the patients or their mothers. Genotypes A and D are predominant in CHB patients in The Netherlands.  相似文献   
539.
BACKGROUND: Erythrocytes are transfused to treat or prevent imminent inadequate tissue oxygenation. 2,3-diphosphoglycerate concentration decreases and oxygen affinity of hemoglobin increases (P50 decreases) with blood storage, leading some to propose that erythrocytes stored for 14 or more days do not release sufficient oxygen to make their transfusion efficacious. The authors tested the hypothesis that erythrocytes stored for 3 weeks are as effective in supplying oxygen to human tissues as are erythrocytes stored for less than 5 h. METHODS: Nine healthy volunteers donated 2 units of blood more than 3 weeks before they were tested with a standard, computerized neuropsychological test (digit-symbol substitution test [DSST]) on 2 days, 1 week apart, before and after acute isovolemic reduction of their hemoglobin concentration to 7.4 and 5.5 g/dl. Volunteers randomly received autologous erythrocytes stored for either less than 5 h ("fresh") or 3 weeks ("stored") to return their hemoglobin concentration to 7.5 g/dl (double blinded). Erythrocytes of the alternate storage duration were transfused on the second experimental day. The DSST was repeated after transfusion. RESULTS: Acute anemia slowed DSST performance equivalently in both groups. Transfusion of stored erythrocytes with decreased P50 reversed the altered DSST (P < 0.001) to a time that did not differ from that at 7.4 g/dl hemoglobin during production of acute anemia (P = 0.88). The erythrocyte transfusion-induced DSST improvement did not differ between groups (P = 0.96). CONCLUSION: Erythrocytes stored for 3 weeks are as efficacious as are erythrocytes stored for 3.5 h in reversing the neurocognitive deficit of acute anemia. Requiring fresh rather than stored erythrocytes for augmentation of oxygen delivery does not seem warranted.  相似文献   
540.
The radiologic features in a patient with breast, pancreatic, and renal non-Hodgkin's lymphoma are presented in this paper. Although diagnosis of lymphoma is based on histologic criteria, radiologic techniques may be helpful in the evaluation and follow-up of masses in patients with lymphoma.  相似文献   
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