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21.
Omphalocele is the most common congenital defect of the abdominal wall. Mortality rate is between 20 and 70% and early closure of the abdominal wall, within 10 days of life, is vital to the successful outcome of the surgical treatment. The authors describe the use of two bipedicled flaps of abdominal skin to correct the defect of the midline as soon as the reduction of all viscera has been accomplished.  相似文献   
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Under normal circumstances, the rate of production of new cells by the epidermis is rather low, but injury results in a burst of mitotic activity that continues until repair is complete. It is now recognized that most cells of the germinative population are in a resting (G0) state, and "postinjury cell renewal" is the consequence of G0 cells entering the mitotic cycle. The biochemical events triggering this process, however, are unknown. Here we show that phorbol myristate acetate (PMA) is able to induce G0 mobilization in the epidermis of the nude mouse. Further, we demonstrate that amiloride (an inhibitor of the membrane Na+-H+ pump), applied topically to human skin, abolishes almost completely the regenerative response after experimental injury. We suggest that activation of the phosphoinositol cycle may initiate recruitment of G0 cells in the epidermis.  相似文献   
26.
Proteinuria in IgA nephropathy   总被引:4,自引:0,他引:4  
Clinicopathological data in 74 patients with IgA nephropathy were analyzed with special attention to level of proteinuria and its prognostic significance in this disease. Excretion rates exceeding 3 g per day (heavy), in the range of 1 to 2.9 g (moderate) and under 1 g per day (mild) each occurred in approximately equal proportions of patients. One-sixth of those with more than 1 g developed end-stage renal failure, while serum creatinine never exceeded 2 mg/dl in any with mild proteinuria. "Renal survival" (serum creatinine of 2 mg/dl or less) at five years after presentation was 100% in patients with persistently mild proteinuria, 87% in those whose protein excretion reached the moderate range, and 69% when heavy or nephrotic range proteinuria developed. Of significance, only rarely did mild proteinuria at presentation increase to higher levels. A correlation existed between level of protein excretion and severity of mesangial, segmental or global proliferation, glomerulosclerosis, podocyte effacement, interstitial infiltration, tubular atrophy and vascular sclerosis, even in patients with unimpaired renal function. Moderate or heavy proteinuria typically preceded the onset of hypertension and occurred prior to the development of renal insufficiency. Our results underscore magnitude of proteinuria as an early marker of glomerular damage in the prognosis of IgA nephropathy.  相似文献   
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Reproduction was studied in male C57B/6 mice treated with contaminated soils from a 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) manufacturing site in Newark, New Jersey, and a metal scrap yard where equipment from the manufacturing site was recycled. The soils contained a wide variety of contaminants including 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). Treated males were mated to females given decontaminated soil. No acute toxicity was observed in treated males. 2,3,7,8-TCDD (up to 90 g/kg) or 2,3,7,8-TCDD from the contaminated soils (up to 288 g/kg) had no adverse effect on reproduction when the male mouse was treated. However, treatment of males with soil from the 2,4,5-T manufacturing site was associated with a marked decrease in viable litters at whelping and a decrease in pup survival. This toxicity may be associated with TCDD in combination with other toxic compounds that are present on the soil.  相似文献   
28.
To investigate the clinical significance of intraoperative cultures in elective abdominal aortic aneurysmectomy, we cultured the aneuryrymml wall and contents in 90 patients undergoing vascular graft surgery. Prosthetic graft infection was documented in 1 out of 62 patients with negative cultures and in none of 28 patients with positive cultures (x2 = 0.4, p > 0.1). Bacterial growth was seen in neither of 2 inflammatory aneurysms, 3 of 14 atherosclerotic aneurysms and 2 of 5 aneurysms without specific features. A retrospective analysis of patients' charts aimed at finding possible risk factors failed to identify any correlation between results of cultures and length of hospitalization before surgery, time interval between angiography and surgery, route of angiography procedure or minutes of surgery before sample collection. We conclude that positive cultures may not imply clinical infection at the time of surgery and that prolonged post-operative organism-specific antibiotic therapy does not appear necessary to prevent graft contamination in patients undergoing elective abdominal aortic aneurysmectomy.  相似文献   
29.
A nodular glomerulopathy characterized by mesangial deposits of monoclonal kappa light chains was detected by immunofluorescence in a renal biopsy from a patient with proteinuria and hypertension. These nodules lacked the tinctorial and morphologic features of amyloid. Ultrastructurally, the nodules contained electron-dense granular deposits as well as fibrils in parallel arrangement. The fibrils measured 110-140 A in diameter. They were consistent in size with amyloid fibrils. However, they differed in lacking the randomly oriented network of typical amyloid fibrils and more closely resembled fibrils intrinsic to mesangial matrix. The patient had no bone marrow or X-ray evidence of myeloma and no evidence of free monoclonal light chains in serum or concentrated urines. Biosynthetic studies of the patient's bone marrow cells demonstrated unbalanced immunoglobulin synthesis with excess production of monoclonal kappa light chains. These observations suggest that the observed glomerulopathy results from direct deposition of monoclonal light chains. Deposits with kappa light chain determinants have been found in 7 other patients with similar nodular glomerulopathies, 4 of whom had diagnosed clinical myeloma. The lesion of nonamyloidotic nodular glomerulopathy previously described in 19 patients, nor examined by immunopathologic techniques or not shown to contain light chain determinants, may have a similar pathogenesis.  相似文献   
30.
Recombination of deltaRec to psiJalpha will delete the TCR delta gene, which is thought to play an important role in the bifurcation of the TCR alphabeta versus TCR gammadelta differentiation lineages. We recently detected a DNA-binding protein in human thymocytes, the so- called PJA-BP, which recognizes the psiJalpha gene segment and might be one of the factors involved in the regulation of preferential deltaRec- psiJalpha rearrangements. We now investigate PJA-BP expression and its correlation with TCR delta gene deletion in thymocytes. Our electrophoretic mobility shift assay experiments showed that the PJA-BP is evolutionary conserved in human, murine and simian thymocytes. Using a large series of human hematopoietic malignancies (n = 30), we conclude that PJA-BP expression is thymocyte specific and seems to be restricted to thymocytes committed to the TCR alphabeta lineage. Analysis of seven well-defined human thymocyte subpopulations showed that preferential deltaRec-psiJalpha rearrangements as well as PJA-BP expression can be detected from the immature CD34-/CD1+/CD3- /CD4+/CD8alpha+beta- thymocyte differentiation stage onwards. These experiments indicate that expression of PJA-BP in human thymocytes starts simultaneously with preferential deltaRec-psiJalpha rearrangements, which supports our hypothesis that PJA-BP is one of the factors involved in the preferential recombination of deltaRec to psiJalpha.   相似文献   
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