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991.
992.
Winkler  TH; Melchers  F; Rolink  AG 《Blood》1995,85(8):2045-2051
Clones and lines of precursor (pre) B cells can be established by limiting dilutions of unseparated cell suspensions of fetal liver or bone marrow on stromal cells in the presence of interleukin (IL)-7. When IL-3 is used instead of IL-7, cultures are regularly overgrown by different precursor cells of the myeloid lineage, as well as by adherent cells that inhibit pre-B-cell expansion. However, in the presence of either IL-7 or IL-3, clones of pre-B cells can be established on stroma cells at frequencies near one in one when the cultures are initiated with cell sorter purified CD45RO (B220)+/c-kit+ fetal liver or bone marrow derived pre-B cells. Clones grown on stromal cells in the presence of IL-7 can be regrown in IL-3, and vice versa. Pre-B cells that proliferate on stromal cells in the presence of IL-7 or IL-3 have the same phenotype, ie, are B220+ c-kit+, CD43+, and surrogate light chain+. Removal of the growth factors (IL-7, respectively IL-3) from the cultures results in differentiation to surface immunoglobulin (slg) positive, c-kit-, CD43-, surrogate light chain- B cells, a fraction of which is lipopolysaccharide (LPS) responsive as shown by IgM secretion. These results show that IL-7 and IL-3 stimulate largely overlapping populations of precursor B cells from bone marrow to proliferate for long periods of time in the presence of stromal cells. Thus, IL-7 and IL-3 are alternative growth factors for the same pre-BI cell.  相似文献   
993.
994.
Consequences of asymptomatic bacteriuria in women with diabetes mellitus   总被引:6,自引:0,他引:6  
BACKGROUND: Women with diabetes mellitus (DM) have asymptomatic bacteriuria (ASB) more often than women without DM. It is unknown, however, what the consequences of ASB are in these women. OBJECTIVE: To compare women with DM with and without ASB for the development of symptomatic urinary tract infections (UTIs), renal function, and secondary complications of DM during an 18-month follow-up period. METHODS: In this multicenter study we monitored women with DM with and without ASB for the development of symptomatic UTIs, renal function, and secondary complications (ie, retinopathy, neuropathy, microvascular, or macrovascular diseases). Data on the first 18-month follow-up period are presented. RESULTS: At least 1 uncontaminated urine culture was available from 636 women (258 with type 1 DM and 378 with type 2 DM). The prevalence of ASB at baseline was 26% (21% for those with type 1 DM and 29% for those with type 2 DM). Follow-up results were available for 589 (93%) of the 636 women. Of these 589 women, 115 (20%) (14% with type 1 DM and 23% with type 2 DM) developed a symptomatic UTI. Women with type 2 DM and ASB at baseline had an increased risk of developing a UTI during the 18-month follow-up (19% without ASB vs 34% with ASB, P =.006). In contrast, there was no difference in the incidence of symptomatic UTI between women with type 1 DM and ASB and those without ASB (12% with ASB vs 15% without ASB). However, women with type 1 DM and ASB had a tendency to have a faster decline in renal function than those without ASB (relative increase in serum creatinine level 4.6% vs 1.5%, P = 0.2). CONCLUSION: Women with type 2 DM and ASB have an increased risk of developing a symptomatic UTI than those without ASB.  相似文献   
995.

Background

Open abdomen (OA) treatment with negative-pressure therapy is a novel treatment option for a variety of abdominal conditions. We here present a cohort of 160 consecutive OA patients treated with negative pressure and a modified adaptation technique for dynamic retention sutures.

Methods

From May 2005 to October 2010, a total of 160 patients—58 women (36?%); median age 66?years (21–88?years); median Mannheim peritonitis index 25 (5–43) underwent emergent laparotomy for diverse abdominal conditions (abdominal sepsis 78?%, ischemia 16?%, other 6?%).

Results

Hospital mortality was 21?% (13?% died during OA treatment); delayed primary fascia closure was 76?% in the intent-to-treat population and 87?% in surviving patients. Six patients required reoperation for abdominal abscess and five patients for anastomotic leakage; enteric fistulas were observed in five (3?%) patients. In a multivariate analysis, factors correlating significantly with high fascia closure rate were limited surgery at the emergency operation and a Bj?rk index of 1 or 2; factors correlating significantly with low fascia closure rate were male sex and generalized peritonitis.

Conclusions

With the aid of initially placed dynamic retention sutures, OA treatment with negative pressure results in high rates of delayed primary fascia closure. OA therapy with the technical modifications described is thus considered a suitable treatment option in various abdominal emergencies.  相似文献   
996.
The goal of hand allotransplantation is to achieve graft survival and useful long-term function. To achieve these goals, precise surgical technique is of critical importance. The key surgical steps and sequence of events in hand allotransplantation are similar to major upper extremity replantations, but are modified to accommodate major conceptual differences that exist between the two procedures.  相似文献   
997.
998.
The diagnosis and epidemiological studies of Q fever depend on serology. Among the main methods employed are the enzyme-linked immunosorbent assay (ELISA) and the immunofluorescent assay test (IFAT). We show that two commercial assays representing the two methods with two different cut-off titres can lead to significant differences in diagnostic and seroprevalence estimates. This in turn emphasizes the need for a standardized gold method to compare the various assays; whether this standard is 'in-house' or commercially obtained.  相似文献   
999.
Background: IgA pemphigus is a rare pustular autoimmune disease with exclusive IgA anti‐keratinocyte cell surface antibody reactivity. Two subtypes have been discerned: in the subcorneal pustular dermatosis type, desmocollin 1 has been identified as a targeted autoantigen, while in few cases of the intraepidermal neutrophilic type, IgA anti‐desmoglein 1 or IgA anti‐desmoglein 3 reactivity has been demonstrated. Patients and Methods: A 48‐year‐old white male presented with generalized large confluent pustules. Skin pathology was assessed by histology and direct immunofluorescence analysis. IgG/IgA autoantibodies against desmoglein 1/3 and desmocollin 1 were measured by ELISA and indirect immunofluorescence using desmocollin 1 cDNA‐transfected COS7 cells, respectively. Results: Histopathology revealed subcorneal pustules and direct immunofluorescence microscopy exclusively showed in vivo bound IgA with an intercellular pattern in the epidermis. Desmocollin 1 was identified as a target of IgA autoantibodies by indirect immunofluorescence microscopy utilizing desmocollin 1 cDNA‐transfected COS7 cells. In addition, IgA anti‐desmoglein 1 reactivity was demonstrated by ELISA. Neither IgA anti‐desmoglein 3 nor IgG anti‐desmoglein 1/3 autoantibodies were present. Conclusions: Both desmocollin 1 and desmoglein 1 were autoantigens in this patient with IgA pemphigus and a distinct clinical presentation. To our knowledge, this is the first IgA pemphigus case with dual autoantibody reactivity.  相似文献   
1000.
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