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991.
The results from the present study demonstrate that the innate defense mechanisms which control the progressive growth of Listeria monocytogenes in normal animals in vivo are dependent upon the active catabolism of endogenous glucocorticoids by the enzyme 11 beta- hydroxysteroid dehydrogenase (11 beta-HSD). When 11 beta-HSD activity was pharmacologically inhibited in vivo, host susceptibility to progressive bacterial disease was markedly increased. Depressed natural resistance following 11 beta-HSD inhibition correlated with changes in the patterns of inducible cytokines by macrophages and T cells. Similar changes were observed when normal adult animals were treated with low doses of dexamethasone prior to experimental infection with Listeria.   相似文献   
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Reactive perforating collagenosis (RPC) in adults commonly manifests in patients with diabetes mellitus. Pruritus and consequent induced scratching have been identified as the bases for the evolution of this skin disease. We present the unusual case of a 55-year-old female diabetic with characteristic umbilicated skin lesions and a long history of scabies. Histology from a crusty nodule revealed transepidermal elimination of collagen. Following antiscabietic treatment, two courses of oral doxycycline demonstrated beneficial effects in controlling the perforating skin disorder.  相似文献   
994.
In renal transplant recipients with type I membranoproliferative glomerulonephritis (MPGN), the posttransplantation course can be complicated by a recurrence of the original disease. However, it is well known that a recurrence of type I MPGN and chronic transplant glomerulopathy (CTG) cannot easily be distinguished. It has been suggested that the two entities can be differentiated by using electron microscopy (EM) and immunofluorescence (IF) techniques. However, studies are lacking that compare biopsy specimens from patients with either a recurrence of type I MPGN or CTG. We have studied renal biopsy specimens from 10 patients with CTG and compared the ultrastructural and IF findings with biopsy specimens from 12 patients with a possible recurrence of type I MPGN. All the patients with CTG showed an electron-lucent zone of finely flocculent material in the subendothelial space, whereas all patients with a recurrence of type I MPGN showed subendothelial electron-dense deposits on EM. On IF, all patients with CTG showed Immunoglobulin M (IgM) with greater intensity than C3. For the patients with recurrent type I MPGN, the opposite was true. Eleven specimens showed C3 deposits with greater intensity than IgM, and in one patient, C3 and IgM were found in equal intensity. In conclusion, when IF and EM studies are available, CTG and recurrence of type I MPGN can reliably be distinguished.  相似文献   
995.
Distal appendicitis: CT appearance and diagnosis   总被引:6,自引:1,他引:5  
Rao  PM; Rhea  JT; Novelline  RA 《Radiology》1997,204(3):709
  相似文献   
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Exciting new research has shown that both preterm and term infants can actively convert the essential fatty acids linoleic acid (LA, 18:2n-6) and α-linolenic acid (ALA, 18:3n-3) to long chain polyunsaturated fatty acids (LCPUFA). However, the amount of LCPUFA being produced, particularly of docosahexaenoic acid (DHA, 22:6n-3), may not be sufficient to meet the developmental requirement of the infant. Because DHA is a major component of retinal and brain tissues, a number of studies have been initiated to test the effect of dietary LCPUFA on neural outcomes in infants. These studies have largely involved a comparison of neural responses from infants fed standard infant formula (no LCPUFA) with infants receiving LCPUFA from either supplemented formula or breast milk. The results have been equivocal and may be due to the variety of LCPUFA supplements and formula fat blends used, differing testing techniques as well as variations in clinical trial conduct, but are clearer in preterm than term infants. Overall the results indicate a possible role for LCPUFA in neurodevelopment.  相似文献   
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