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991.
Pericarditis with hemodynamic compromise is a rare manifestation of infection with Nocardia asteroides. To our knowledge, only six cases have been reported previously. In contrast to other cases of pericardial disease due to Nocardia, culture of the pericardial fluid in our case was negative while culture of pericardial tissue led to the diagnosis. Surgical intervention and appropriate antibiotic therapy are essential in the treatment of Nocardia pericarditis.  相似文献   
992.
The terminal bowel is congenitally aganglionic in ls/ls mice. The condition has been associated with an overabundance of laminin and other matrix molecules. Aggregation ls/ls<==>C3H chimeric mice and interspecies mouse<==>quail chimeras were constructed to test the hypothesis that the aganglionosis arises because the ls/ls gut and not the neural crest is abnormal. Demonstration of beta-glucuronidase activity permitted genotypically ls/ls and C3H cells to be distinguished in the ls/ls<==>C3H chimeras. Aganglionosis did not occur in the ls/ls<==>C3H mice and ls/ls neurons were observed in the terminal bowel. Following bactransplantation of control segments of mouse gut into quail host embryos, mouse cells migrated to host targets normally colonized by cells from the neural crest; moreover, quail crest-derived cells entered the mouse gut. In contrast, cells did not migrate to these targets from presumptive aganglionic ls/ls bowel and quail crest-derived cells neither entered the ls/ls gut nor migrated through it. Laminin immunoreactivity was present in the backgrafts of murine colon and was far more abundant and widespread in those from ls/ls than in those from control animals. These data suggest that the presumptive aganglionic ls/ls bowel does not contain crest-derived cells because these cells, which are normal in ls/ls mice, do not enter it. This failure of colonization may be related to the premature formation of neurons outside the abnormal gut, a response that may be promoted by the excessive secretion of laminin by the ls/ls enteric mesenchyme.  相似文献   
993.
Thirty-two patients with sight-threatening uveitis and a decrease in visual acuity requiring systemic therapy were randomly assigned to either cyclosporine A or G in a dose-escalation study. Groups received from 2.5 mg/kg of body weight/day to 10 mg/kg of body weight/day of either drug along with low-dose prednisone. More patients taking cyclosporine G had improved visual acuity and a decrease in macular edema, which occurred more rapidly than in the other group, even at the lower doses tested. No difference in renal function was noted between groups at any doses tested. Four patients receiving cyclosporine G had hepatic alterations, but only one required cessation of the drug. The study indicates the potential usefulness of cyclosporine G, particularly at lower doses (4 mg/kg of body weight/day), which could lower the potential for serious renal complications.  相似文献   
994.
995.
Multiple endocrine neoplasia type 1 (MEN1) is a hereditary syndrome characterized by the involvement of several endocrine glands, including the parathyroid glands, the pancreatic islet cells, the anterior pituitary gland and other neuroendocrine tissues. In order to build up a French MEN1 register, a collaborative network was developed through the 'Groupe d'Etude des Néoplasies Endocriniennes Multiples de type 1' or GENEM 1. A 2-year follow-up in 40 medical and surgical units allowed the identification of more than 150 individual patients and 45 MEN1 families, and defined the major clinical features of the disease in our series. Multiple endocrine neoplasia type 1 is inherited as an autosomal dominant trait. The gene causing this syndrome has been localized to chromosome 11, band 11q13, and molecular genetic markers flanking the MEN1 locus are of use in identifying disease gene carriers in predisposed families. Selected data were presented in order to discuss the management of patients by combined clinical, biochemical and genetic screening. The set-up of a national register by a multi-disciplinary and collaborative medical and surgical network will facilitate further research on the clinical management of MEN1 patients and the basic physio-pathology of the disease.  相似文献   
996.
A modification of the Roux-en-Y anastomosis procedure was used to bypass a pyloroduodenal mass in a 12-year-old Arabian stallion. Clinical signs had consisted of a 4-week progression of ventral and hind limb edema, hypoproteinemia, fecal occult blood, intermittent abdominal pain, weight loss, and gastric reflux. On exploratory celiotomy, an obstructive mass was found in the pylorus and proximal portion of the duodenum. Gastrojejunostomy and duodenojejunostomy were performed by use of stapled side-to-side anastomosis techniques. Inaccessibility of the obstructed pyloric region prevented resection of the affected area.  相似文献   
997.
Vascular injury is not uncommon in cases of major pelvic trauma. Venous injury is by far the most common associated problem and may lead to exsanguinating hemorrhage. Arterial injury is less common, but certainly not without associated morbidity and mortality. It can lead to persistent bleeding after fixation and stabilization of the pelvic girdle, and occlusion of major pelvic arteries can cause limb ischemia and limb loss. The potential problems with revascularizing the ischemic extremity are (1) other life-threatening injuries that may be present and (2) a retroperitoneal hematoma that can interfere with an anatomic approach. Our solution to the latter problem, as presented here, is placement of a cross-femoral bypass graft, which rapidly and safely restores blood flow in the presence of pelvic fracture and an occluded external iliac artery. The pelvic hematoma is avoided, thereby restoring circulation more quickly, with less blood loss and greater ease.  相似文献   
998.
BACKGROUND: The evaluation and treatment of Jefferson fractures, a burst fracture of the ring of Cl, has been well documented in the medical literature. Vertebral artery injury associated with a Jefferson fracture is very rare. METHODS: The case study technique was used to summarize the case. Review of the literature was performed to discuss the case. Retrospective chart review of the 174 patients with cervical fractures admitted to St. Michael's Hospital from 1989-1994 was also performed. RESULTS: The case of a patient with a Jefferson fracture, with bilateral lateral displacement of the lateral masses causing bilateral vertebral artery occlusions resulting in a lateral medullary and cerebellar infarction is reported. A review of the literature is provided. CONCLUSION: A high index of suspicion for this injury is paramount, especially in patients with multiple trauma, where the diagnosis of Jefferson fractures can be delayed.  相似文献   
999.
1000.
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