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81.
82.
Summary We studied the effects of repeated intra-articular injections of sterile 140 mM NaCl solution on articular cartilage in adult rabbits. After 20 injections into the knee joints over a period of 4 weeks, chondrocyte glucosaminoglycan synthesis was evenly reduced in all cartilage layers, accompanied by a significant proteoglycan depletion of the matrix which was most marked in the superficial half of the cartilage. These and other changes only partially reversed during a further 4-week period after the injections had been stopped. Our data underline the need for a clear-cut indication for intra-articular injections. The microtrauma caused by injection, in conjunction with the introduction of a carrier solution into the joint, may, at least when repeated at short intervals, lead to measurable damage to the articular cartilage.Recipient of grant no. Ne 308/1-1 from the Deutsche Forschungsgemeinschaft, Bonn, Germany  相似文献   
83.
OBJECTIVE: To determine the in vitro stability of endogenous and recombinant erythropoietin (EPO) incubated at 37 degrees C in amniotic fluid (AF) and fetal plasma. STUDY DESIGN: Endogenous and recombinant EPO in AF, fetal plasma and phosphate buffer were incubated in vitro for 21 days at 37 degrees C. Serial aliquots were analyzed for EPO and the rates of EPO decline were compared within and between groups. RESULTS: Endogenous and recombinant EPO declined significantly in plasma and AF at 37 degrees C. Endogenous EPO displayed a similar linear rate of decline in AF and plasma, with nearly 70% of the initial hormone concentration remaining at 21 days. Recombinant EPO incubated in buffer did not change. CONCLUSIONS: Using the rate of decline in endogenous EPO we observed, EPO levels measured in AF or plasma within 21 days of fetal demise can be extrapolated back to the level likely present at fetal death.  相似文献   
84.
Vacuum Assisted Closure brand Negative Pressure Wound Therapy (V.A.C. NPWT) has been shown to be an effective therapeutic option for the treatment of recalcitrant wounds; however, the mechanism of action at the cellular level remains to be elucidated. Here, we examined the effects of negative pressure wound therapy, manifolded with two different dressings, on fibroblast viability, chemotactic signaling, and proliferation in a fibrin clot matrix. Fibroblasts were grown in a three-dimensional fibrin matrix and were treated for 48 hours with either V.A.C. NPWT and GranuFoam Dressing, or with gauze under suction, or as static controls without negative pressure or dressings. Cells treated by gauze under suction showed significantly greater cell death and stimulated less migration and proliferation than static and V.A.C. NPWT-treated cells (p<0.05). Apoptosis was also significantly higher in gauze under suction than in static treatments. These results indicate that the dressing material has a significant effect on cell response following negative pressure wound therapy. The ability to support cell growth, stimulate chemotaxis, and proliferation without increasing apoptosis may provide an insight into the mechanisms of action of V.A.C. NPWT.  相似文献   
85.
The aim of this study was to determine whether plasma concentrations of the acyl (AcMPAG) and phenolic (MPAG) glucuronide metabolites of mycophenolic acid (MPA) were related to diarrhoea in renal transplant patients on mycophenolate mofetil (MMF) with cyclosporine (CsA) or tacrolimus (TCL). Blood samples (0, 30, 120 min) were taken at days 3, 10, week 4, months 3, 6 and 12 for determination of MPA, MPAG and AcMPAG. MPA-AUC was estimated using validated algorithms. Two hour AUCs were calculated for MPAG and AcMPAG. Immunosuppressive therapy consisted of CsA/MMF (n= 110) and of TCL/MMF (n= 180). In 70/290 (24%) patients 86 episodes of diarrhoea were recorded during 12 months. Significantly more patients on TCL (31.1%) suffered from diarrhea compared to CsA (12.7%). MMF dose, MPA-AUC and the 2 h AUCs of MPAG and AcMPAG did not differ between patients with and without diarrhoea. Plasma AcMPAG and MPAG concentrations were substantially higher in patients on CsA compared with TCL, while MPA-AUC was lower in the former group. These data support the concept that CsA inhibits the biliary excretion of MPAG and AcMPAG, thereby potentially reducing the risk of intestinal injury through enterohepatic recycling of MPA and its metabolites.  相似文献   
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Introduction Postoperative treatment for colorectal cancer depends on tumor stage as defined by the International Union Against Cancer (UICC). Adjuvant chemotherapy is not recommended in patients without lymph node involvement (UICC stages I and II). As many as 20–30% of these patients, however, will develop recurrence. Aims and objectives We conducted this study to determine the presence of disseminated tumor cells in the lymph nodes by quantitative real-time polymerase chain reaction (QRT-PCR) for cytokeratin 20 (CK20) in an attempt to provide supplementary information compared to histopathological findings. Materials and methods Using a standard QRT-PCR assay, we examined primary tumors and 391 lymph nodes from 31 patients with completely resected colorectal cancer. Results Of the 31 primary tumors, 29 were positive for CK20 by QRT-PCR. Discussion An examination of the lymph nodes from the 29 patients with CK20-positive primary tumors revealed that 35 (92.1% sensitivity) of the 38 histopathologically positive lymph nodes and 54 (16.7%) of the 324 histopathologically negative lymph nodes were positive by molecular analysis. CK20 expression was detected in 10 (100%) of 10 patients with a histopathologically positive lymph node status (pN1). In 9 (47.4%) of 19 patients with negative histopathological results (pN0), we detected a CK20 mRNA signal in at least one lymph node. Whereas eight patients with histopathologically negative lymph nodes could be upstaged on the basis of the molecular findings, no patient would be downstaged. Conclusion Our results suggest that QRT-PCR for CK20 is a useful tool for the quantitative detection of micrometastases in the regional lymph nodes. We introduce a standardized procedure that integrates a molecular diagnostic technique in the clinical staging.  相似文献   
88.
PURPOSETo determine whether arteriolar vessel wall degeneration in primary intracerebral hematomas might be associated with ischemic brain lesions and clinically silent (apparently intracerebral) previous hemorrhages.METHODSThe MR images of 120 consecutive patients (mean age, 60 years; age range, 22 to 84 years) with their first stroke caused by a primary intracerebral hematoma were reviewed retrospectively for coexisting ischemic damage and previous bleeds.RESULTSEarly confluent to confluent white matter hyperintensities, lacunes, or infarction were present in 83 (69%) of the patients, and 39 (33%) had had previous hemorrhages consisting of microbleeds or old hematomas. Extensive white matter hyperintensities and lacunes were most frequent in patients with thalamic primary intracerebral hematomas. There was no relationship between the frequency of old hemorrhages and the location of subsequent primary intracerebral hematomas.CONCLUSIONClinically silent ischemic lesions and previous hemorrhages are a common finding on MR images of patients with primary intracerebral hematoma. They may therefore serve as evidence of diffuse microangiopathy with a possible increased risk for cerebral hemorrhage.  相似文献   
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A 60 year old male patient is introduced who developed a loss of vision caused by chorioretinal cystic alteration in the macula of the left eye 9 months after a routine extracapsular cataract surgery with implantation of posterior chamber lens. There existed no other general symptoms, hematologic values and serology were regular. Having discussed literature the diagnosis of solitary Toxocara canis granuloma was produced.  相似文献   
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