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Based upon the percentage of cases of IgA nephropathy (IgAN) in biopsy series, a lower prevalence has been assumed for African-Americans compared with Americans of European descent. This may be due to a racial difference in the basic underlying pathology of IgAN or to racial differences in patterns of referral and biopsy selection practices. Over the past decade (1985 – 1994), we have found similar incidences of IgAN in Caucasian and African-American children from Shelby County, Tennessee. The incidence was 3.0 cases per million per year for Caucasian and 5.7 cases per million per year for African-American children. IgAN may be more common in African-American children than previously appreciated. Population-based incidence studies will be necessary to determine whether or not our experience has become a more widespread phenomenon. Received August 21, 1996; received in revised form and accepted December 18, 1996  相似文献   
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Activation of the complement cascade occurs in most cases of acute poststreptococcal glomerulonephritis (APSGN) and results in the formation of the terminal complement complexes (TCC). To examine the possible role of TCC in the pathogenesis of glomerular injury in APSGN, we studied 30 patients with the clinical diagnosis of APSGN. All patients had an elevated plasma SC5b-9 concentration at the onset of clinical nephritis. Serial plasma concentrations showed an inverse linear relationship with time after onset of clinical disease (r=–0.59,P=0.0008), while plasma C3 concentrations showed a positive linear relationship (r=0.78,P=0.0001). Renal biopsies of 5 patients demonstrated co-localization of C5b-9, S-protein, and C3 deposition in a glomerular capillary loop and mesangial distribution. Urinary excretion of TCC in the acute phase of APSGN was not elevated and was not a useful marker of disease activity. These data suggest that in APSGN with terminal complement pathway activation the local generation of TCC may contribute to the pathogenesis of the disease.  相似文献   
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This study aimed to examine the side effects of selected neonicotinoids (Acetamiprid, Aceta, and Imidacloprid, Imid) on Oreochromis niloticus juveniles. The acute toxicity, Probit method, revealed an LC50 of 195.81 and 150.76 ppm for Aceta/96 h and Imid/72 h respectively. The fish were divided into three groups that were exposed, for 21 days (n?=?5/replicate), to 1/10 of the LC50 of either neonicotinoids, however, the third was an unexposed control group. Results of erythrocytic micronucleus (MN), and nuclear abnormalities (NA) showed that Aceta and Imid exposure caused a significant (p?<?0.05) increase in MN by?~?2.2 and?~?10 folds, respectively relative to control. NAs occurred at the order of kidney-shaped?>?budding?>?binucleated in Aceta, however, budding?>?binucleated?>?kidney-shaped was noticed in the Imid group. Histopathological changes in gills, liver, and muscles were observed significantly in both exposed groups with more severity in the Imid group. Collectively, Aceta and Imid have potential genotoxicity and histopathological alterations in O. niloticus.

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INTRODUCTION: Previous studies have suggested that African-American (AA) ethnicity is a risk factor for rejection and graft loss after kidney transplantation. However, little data is available regarding outcomes after simultaneous kidney pancreas transplantation (SKPT) in AA recipients. The objective of this study was to compare the outcomes of SKPT in AA patients to matched Caucasian patients as controls. METHODS: From January 1996 to September 1999, we performed 79 SKPTs, including 10 in AA recipients. Ten Caucasian controls were selected and matched for age, gender, weight, timing and technique of transplantation, and immunosuppressive regimen. Clinical outcomes were collected and compared between the two groups. RESULTS: The two groups were well matched for donor and recipient demographic, immunologic and transplant characteristics, including 2 patients in each group with type 2 diabetes. All patients received tacrolimus (TAC), mycophenolate mofetil (MMF) and steroids, and about half in each group received antibody induction therapy. Patient survival was 100% in both groups with a mean follow-up of 18 months (range 6 47). Kidney and pancreas graft survival rates were both 80% in the AA and 100% in the Caucasian groups, respectively (p = 0.14). All but one kidney (in the AA group) and all pancreas grafts experienced immediate function. There were two immunologic kidney and two immunologic pancreas graft losses in the AA group. No grafts were lost due to technical problems. The mean length of initial hospital stay was 16 d in the AA group compared to 10 d in the Caucasian group (p = 0.07). The AA group had a slight increase in the number of readmissions (mean 2.2 AA vs. 1.6 Caucasian, p = 0.08). The incidence of biopsy-proven pancreas acute rejection was significantly higher in the AA group (50%) compared to the Caucasian group (10%) (p = 0.05). The incidence of either kidney or pancreas acute rejection was also higher in the AA group (60% AA vs. 20% Caucasian, p = 0.06). TAC levels were comparable at specific times after transplantation, al-though there was a trend toward higher doses of TAC in the AA group to achieve therapeutic levels. The incidences of relaparotomy (30% AA vs. 20% Caucasian) and major infection (40% AA vs. 60% Caucasian) were similar between groups. Renal and pancreas allograft functions were comparable between groups at specific times after transplantation. CONCLUSIONS: These results suggest that SKPT in AA recipients may be associated with a higher incidence of rejection and immunologic graft loss compared to matched Caucasian controls.  相似文献   
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We reviewed the literature for different diagnostic approaches for dry eye disease (DED) including the most recent advances, contradictions and promising diagnostic tools and technique. We performed a broad literature search for articles discussing different methods for diagnosis of DED including assessment of tear osmolarity, tear film stability, ocular biomarkers and others. Articles indexed in PubMed and google scholar were included. With the growing cosmetic industry, environmental pollution, and booming of digital screens, DED is becoming more prevalent. Its multifactorial etiology renders the diagnosis challenging and invites the emergence of new diagnostic tools and tests. Diagnostic tools can be classified, based on the parameter they measure, into tear film osmolarity, functional visual acuity, tear volume, tear turnover, tear film stability, tear film composition, ocular biomarkers and others. Although numerous methods exist, the most accurate diagnosis can be reached through combining the results of more than one test. Many reported tests have shown potential as diagnostic/screening tools, however, require more research to prove their diagnostic power, alone or in combination. Future research should focus on identifying and measuring parameters that are the most specific to DED diagnosis.  相似文献   
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Soft tissue chondroma is an uncommon soft-tissue cartilaginous tumor of benign nature, it considers a variant of extra-skeletal chondromas that undergoes extensive ossification. This case of a 37?years old Egyptian male presented with a recurrent slowly growing painful palpable heel mass arises at the plantar aspect of his RT foot.The case is pathologically proven to be benign soft tissue chondroma.  相似文献   
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