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81.
Incubation of polymorphonuclear leukocytes (PMNs) in fusidic acid resulted in a decrease of random migration and chemiluminescence. The effects were dose-dependent but moderate, with statistical significance only at concentrations of 50 mg/l or more. At concentrations used for therapy of bacterial infections and AIDS, fusidic acid was not shown to be deleterious to these aspects of PMN function.  相似文献   
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During the past decade, rotavirus genotype G9 has spread throughout the world, adding to and sometimes supplanting the common genotypes G1-G4. We report evidence of this spread in a population sample within rural Ecuador. A total of 1,656 stool samples were collected from both patients with diarrhea and from asymptomatic residents in 22 remote communities in northwestern Ecuador from August 2003 through February 2006. Rotavirus was detected in 23.4% of case-patients and 3.2% of controls. From these 136 rotavirus-positive samples, a subset of 47 were genotyped; 72% were of genotype G9, and 62% were genotype P[8]G9. As a comparison, 29 rotavirus-positive stool samples were collected from a hospital in Quito during March 2006 and genotyped; 86% were of genotype P[8]G9. Few countries have reported P[8]G9 rotavirus detection rates as high as those of the current study. This growing prevalence may require changes to current vaccination programs to include coverage for this genotype.  相似文献   
84.
A 45-kb R plasmid, pRAS1, that confers resistance to tetracyclines, trimethoprim, and sulfonamides was isolated in 1989 from an atypical strain of the fish pathogen Aeromonas salmonicida. This plasmid could be transferred by conjugation to Escherichia coli with a high degree of efficiency (frequency, 0.48). The following year pRAS1 was isolated from A. salmonicida subsp. salmonicida in the same area. Incompatibility group U plasmid pRAS1 contained a drug resistance-determining region of 12 kb consisting of a class 1 integron similar to In4 of Tn1696 but with a dfrA16 gene cassette inserted. Close to IS6100 at the right end of Tn4 was a truncated Tn1721. Restriction enzyme analysis showed that R plasmid pAr-32, isolated from A. salmonicida in Japan in 1970, had the same backbone structure as pRAS1, while the drug resistance-determining region contained a complex class 1 integron with an aadA2 cassette; the chloramphenicol resistance gene catA2, as in In6 of pSa; and a duplicate of the 3' conserved segment of the integron.  相似文献   
85.
OBJECTIVE: To analyze experience with total parenteral nutrition (TPN) for hematopoietic stem cell transplantation (HSCT) at our institution compared with reports in the literature. PATIENTS AND METHODS: We reviewed medical records of 100 patients (53 men and 47 women) who underwent HSCT from 1992 to 2001. Data were abstracted on demographics, primary diagnosis, type of transplantation, myeloablative regimen, length of hospital stay, time to engraftment, 1- and 5-year survival, initiation and duration of TPN, and TPN-related complications. RESULTS: Seventy-one transplantations were autologous, 27 allogeneic, and 2 syngeneic. The median age of the patients was 51 years (range, 19-71 years). We initiated TPN when patients' oral caloric intake was less than 50% of their estimated needs (4 to 7 days after the start of myeloablative therapy; median, 1.2 days after HSCT; range, 8 days before HSCT to 13 days after HSCT). We discontinued TPN when oral intake was more than 50% of estimated needs (median duration, 16 days for autologous and 24 days for allogeneic transplantations, with the shortest duration in breast cancer patients and the longest duration in those treated with cyclophosphamide). Mean weight loss was less than 2%. No differences in patient characteristics, myeloablative regimen, or diagnosis were observed between patients who required and those who did not require TPN. Infection, hospital stay, time to engraftment, and mortality were comparable to published reports. CONCLUSION: In patients undergoing HSCT, TPN should not be initiated until oral caloric intake is less than 50% of estimated needs. During the period of inadequate oral intake, TPN maintains stable body weight with longer duration of support needed for patients undergoing allogeneic than for those undergoing autologous transplantations.  相似文献   
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Background Matrix metalloproteinases (MMPs) and the tissue inhibitors of MMPs (TIMPs) have been demonstrated to be involved in inflammatory conditions in the intestine. The purpose of this study was to investigate whether the alterations of the MMP/TIMP balance might reflect the course of the inflammatory process in acute appendicitis and if the expression and localisation of MMPs and TIMP is variable in the various clinical manifestations of appendicitis. Materials and methods The study comprises 40 patients (26 men and 14 women) having emergency appendectomy and a control group constituting of 10 patients (5 men and 5 women) having a hemicolectomy for other reasons. MMP and TIMP expressions were assessed and compared in tissue specimens from phlegmonous (n = 15), gangrenous (n = 7), perforated appendicitis (n = 11) and controls with noninflamed appendices (n = 10) by means of enzyme-linked immunosorbent assay technique. Localisation of the enzymes was performed by immunohistochemistry. Results MMP-1 was significantly higher in gangrenous and perforated appendicitis compared with phlegmonous appendicitis and controls (p < 0.05) while MMP-2 was significantly lower in gangrenous appendicitis compared with phlegmonous appendicitis and controls. MMP-2 was also lower in perforated appendicitis when compared with controls (p < 0.01). Elevated expression of MMP-9 was demonstrated in all groups of appendicitis compared with the controls (p < 0.001). Conclusions MMP-9 is the most abundantly expressed MMP of those investigated in inflamed appendix. We postulate that a local imbalance between MMP-9 and TIMP-1 may trigger a perforation. These results suggest that MMPs might be useful as biomarkers of appendices prone to perforation.  相似文献   
88.
Objectives: To measure continuity among medical groups of insured patients over a 5-year period and to test whether group continuity of care is associated with healthcare utilization and costs. Study Design: Retrospective observational study. Methods: We studied natural patient behavior by using insurance claims data in the absence of any medical group or health plan incentives for continuity. We conducted the study through a retrospective analysis of administrative data of 121,780 patients enrolled from 2005 to 2009 in HealthPartners, a large nonprofit Minnesota health plan. Each year, patients were attributed to the medical group where they received the greatest number of primary care visits. Multilevel multiple regression models were used to estimate the association of annualized medical cost and utilization with attribution and continuity categories. Results: Although patients with high medical group continuity were older and had more comorbidities than patients with medium or low continuity of care, they had a consistently lower probability of any inpatient expenditure or any emergency department (ED) utilization and lower total medical costs. Conclusions: Although a small proportion, health plan members who visited a primary care provider but had low or medium continuity among medical groups had higher inpatient and ED use than those with high continuity. Improved coordination and integration has potential to lower utilization and costs in this group.  相似文献   
89.
The relationship between sulfonamide susceptibility and the ability to liberate endotoxin was studied in 50 strains of Neisseria meningitidis. The endotoxin activity was investigated by the Limulus lysate test in growing cultures of 25 sulfonamide-resistant and 25 sensitive strains. The sulfonamide-resistant strains tended to have a higher endotoxin activity in cultures grown for 6 h than sensitive ones, and had also a higher amount of free, filtrable endotoxin.  相似文献   
90.
It is well established that cultured endothelial cells are induced to generate tissue factor activity when incubated with either endotoxin or thrombin. In this study a perfusion system was used on 3-4 cm long human saphenous veins. The veins were perfused with thrombin (2.5 U/ml), endotoxin (30 ng/ml) or just medium for 3 h at 37 degrees C. After the perfusion, the veins were treated with collagenase, and EC were collected and subjected to tissue factor activity measurements. Some perfused veins were examined for tissue factor activity on the vessel wall by allowing factor VII and factor X to interact with the lumen of the intact vessels, followed by quantitation of generated factor Xa in a chromogenic assay. No formation of tissue factor activity could be found after perfusion in either collagenase-dissolved endothelial cells or in the coupled chromogenic assay for tissue factor activity performed in the lumen of the vessel. Our data strongly suggest that endothelial cells in intact endothelium may behave quite differently from isolated endothelial cells stimulated in cell cultures.  相似文献   
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