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1.
Fabian Doerr Akmal M. A. Badreldin Ferzen Can Ole Bayer Thorsten Wahlers 《Scandinavian cardiovascular journal : SCJ》2014,48(2):111-119
Objectives. Cardiac surgery patients are excluded from SAPS2 but included in SAPS3. Neither score is evaluated for this exclusive population; however, they are used daily. We hypothesized that SAPS3 may be superior to SAPS2 in outcome prediction in cardiac surgery patients. Design. All consecutive patients undergoing cardiac surgery between January 2007 and December 2010 were included in our prospective study. Both models were tested with calibration and discrimination statistics. We compared the AUC of the ROC curves by DeLong's method and calculated OCC values. Results. A total of 5207 patients with mean age of 67.2 ± 10.9 years were admitted to the ICU. The mean length of ICU stay was 4.6 ± 7.0 days and the ICU mortality was 5.9%. The two tested models had acceptable discriminatory power (AUC: SAPS2: 0.777–0.875; SAPS3: 0.757–893). SAPS3 had a low AUC and poor calibration on admission day. SAPS2 had poor calibration on Days 1–6 and 8. Conclusions. Despite including cardiac surgery patients, SAPS3 was not superior to SAPS2 in our analysis. In this large cohort of ICU cardiac surgery patients, performance of both SAPS models was generally poor. In this subset of patients, neither scoring system is recommended. 相似文献
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����ϲ����ӧ��������������ѧ�������������¹⸣���ߺ�Ӣ�����ĸ������������¹����� 《中国实用儿科杂志》2014,29(11):845-848
??Abstracts?? Objective To study the T2* magnetic resonance imaging for evaluation of iron deposition of liver?? pancreas and heart in β- thalassemia major ??β-TM?? patients and the relationship of the serum ferritin with iron overload. Methods Measurement of hepatic?? pancreatic and cardiac MRI T2* was performed in 153 patients with β-TM from May 1?? 2010 to December 31?? 2010??The demographics and serum ferritin ??SF?? were collected. The rate of the iron overload in liver?? pancreas and heart was analyzed. The rates of combined pancreatic and cardiac iron overload in different hepatic iron overload groups were compared. Results According to MRI T2*?? there was serious hepatic iron overload in 85 cases?? moderate in 39?? mild in 21?? no iron overload in 8. Similarly?? there was pancreatic iron overload in 134?? no iron overload in 19. In terms of cardiac iron overload?? there was serious cardiac iron overload in 37 cases?? mild in 21?? no iron overload in 95. No correlation was found between hepatic?? pancreatic and cardiac MRI T2* and age or SF?? but hepatic MRI T2* correlated with pancreatic and cardiac MRI T2*??P = 0.000?? r = 0.529?? r = 0.369???? and pancreatic MRI T2* correlated with cardiac MRI T2* well ??P = 0.000?? r = 0.715??. As grade of hepatic iron overload increases?? the patients demonstrated higher rate of combination of pancreatic and cardiac iron overload simultaneously ??χ2 = 20.78??P = 0.000??. 相似文献
5.
A long-term study of 370 autotransplanted premolars. Part II. Tooth survival and pulp healing subsequent to transplantation 总被引:3,自引:0,他引:3
J O Andreasen H U Paulsen Z Yu T Bayer O Schwartz 《European journal of orthodontics》1990,12(1):14-24
The purpose of the present investigation was to determine the long-term prognosis of autotransplanted premolars with respect to tooth survival and pulpal healing. The material consisted of 195 patients aged 7 to 35 years, with a total of 370 autotransplanted premolars with observation period ranged from 1 to 13 years. Teeth transplanted with incomplete and complete root formation showed 95 per cent and 98 per cent long-term survival respectively: Pulp healing as evaluated by sensibility testing and radiographic signs of partial pulp canal obliteration was usually verified 6 months after transplantation. The frequency of pulpal healing (versus pulp necrosis), appeared to be closely related to stage of root development at time of transplantation. Teeth transplanted with incomplete and complete root formation showed 96 per cent and 15 per cent pulp healing respectively. Another and associated factor which could equally well predict pulpal healing was the diameter of the apical foramen of the graft. Finally, in teeth with completed root formation, the use of bursa with internal cooling and no extra-alveolar storage prior to transplantation seemed to increase the chance for pulpal healing. The present study indicates, that the size of the apical foramen and possibly the avoidance of bacterial contamination during the surgical procedure are explanatory factors for pulpal healing. 相似文献
6.
Enkling N Jöhren P Klimberg V Bayer S Mericske-Stern R Jepsen S 《Clinical oral implants research》2011,22(10):1185-1192
Objective: The concept of platform switching has been introduced to implant dentistry based on observations of reduced peri‐implant bone loss. However, randomized clinical trials are still lacking. This study aimed to test the hypothesis that platform switching has a positive impact on crestal bone‐level changes. Material and methods: Two implants with diameters of 4 mm were inserted epicrestally into one side of the posterior mandibles of 25 subjects. After 3 months of submerged healing, the reentry surgery was performed. On the randomly placed test implant, an abutment 3.3 mm in diameter was mounted, resulting in a horizontal circular step of 0.35 mm (platform switching). The control implant was straight, with an abutment 4 mm in diameter. Single‐tooth crowns were cemented provisionally. All patients were monitored at short intervals over the course of 1 year. Standardized radiographs and microbiological samples from the implants' inner spaces were obtained at baseline (implant surgery), and after 3, 4, and 12 months. Results: After 1 year, the mean radiographic vertical bone loss at the test implants was 0.53±0.35 mm and at the control implants, it was 0.58±0.55 mm. The mean intraindividual difference was 0.05±0.56 mm, which is significantly <0.35 mm (P=0.0093, post hoc power 79.9%). The crestal bone‐level changes depended on time (P<0.001), but not on platform switching (P=0.4). The implants' internal spaces were contaminated by bacteria, with no significant differences in the total counts between the test and the control at any time point (P=0.98). Conclusions: The present randomized clinical trial could not confirm the hypothesis of a reduced peri‐implant bone loss at implants restored according to the concept of platform switching. To cite this article: Enkling N, Jöhren P, Klimberg V, Bayer S, Mericske‐Stern R, Jepsen S. Effect of platform switching on peri‐implant bone levels: a randomized clinical trial. Clin. Oral Impl. Res. 22 , 2011; 1185–1192.doi: 10.1111/j.1600‐0501.2010.02090.x 相似文献
7.
Dr. A. Kropec J. Huebner M. Riffel U. Bayer A. Benzing K. Geiger F. D. Daschner 《Intensive care medicine》1993,19(3):161-165
Objective A 4 month prospective study was performed to assess the incidence and routes of endogenous or exogenous colonization and nosocomial infection caused byStaphylococcus aureus andPseudomonas aeruginosa in surgical critically ill patients.Design A total of 4634 specimens ware obtained. Patient's nasal, scalp, and rectal swabs as well as tracheal secretion (TS) were cultured every second day beginning on the day of admission. Nasal swabs and hand cultures of the personnel as well as cultures from gowns were also taken. all isolates ofS. aureus were phage typed and 116 of these isolates were also plasmid typed.P. aeruginosa isolates were sero-and pyocin typed. Resistance patterns were determined in all isolates.Setting The suty was carried out in the surgical intensive care unit (SICU) of an teaching hospital.Patients During the study period each patient (a total of 153 patients) admitted to the SICU entered the study.Results
P. aeruginosa andS. aureus colonisation rate on admission were 5% and 36.5% respectively. Only 10 patients (6.5%) were colonized withP. aeruginosa during hospitalization, and only 7 patients (4.5%) acquiredS. aureus in the surgical intensive care unit (SICU). The most common primary colonisation site ofP. aeruginosa was the rectum, whereasS. aureus was predominantly found in nasal cultures. Horizontal transmission ofS. aureus occured in only 2 patients.Conclusion The study suggests that colonisation withP. aeruginosa andS. aureus occurs from endogenous rather than from exogenous sources and that the endogenous acquisition of both bacteria play a more important role in development of nosocomial infections than the exogenous route of transmission. 相似文献
8.
HJ Alter ; GE Tegtmeier ; BW Jett ; S Quan ; JW Shih ; WL Bayer ; A Polito 《Transfusion》1991,31(8):771-776
Samples from prospectively followed recipients, their respective donors, and a cohort of random donors were used to evaluate the specificity and efficacy of a recombinant immunoblot assay (RIBA) as an adjunct to anti-hepatitis C virus (HCV) testing by enzyme immunoassay (EIA). RIBA reacted (RIBA+) in 100 percent of patients who developed hepatitis associated with anti-HCV seroconversion documented by EIA and in 100 percent of the EIA-positive (EIA+) donors implicated in these cases. In contrast, RIBA reacted in none of 10 recipients who were EIA+ but did not develop hepatitis, in none of 7 EIA+ patients with hepatitis B or cytomegalovirus infection, in 33 percent of EIA+ donors who were not implicated in hepatitis transmission, and in 37 percent of EIA+ random donors. Hence, the vast majority of EIA+ individuals who have ancillary evidence of HCV infection react on RIBA, whereas the majority of EIA+ individuals in low-risk settings do not react (RIBA-negative, or RIBA-). There was a strong association between RIBA reactivity and the presence of a surrogate marker (elevated alanine aminotransferase [ALT] and/or antibody to hepatitis B core antigen); 43 percent of RIBA+ implicated donors had a surrogate marker as compared to none of 14 EIA+, RIBA- donors. Among EIA+ random donors, 77 percent of those with a surrogate marker were RIBA+, as compared with 29 percent of those without a surrogate marker. In addition, in EIA+ donors, RIBA reactivity correlated with the extent of ALT elevation; 86 percent of those with an ALT greater than 135 IU per L were RIBA+ compared with 18 percent of those with an ALT less than 30 IU per L.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
9.
Intravegetation host inflammatory cell function may play a role in the more salutary clinical outcomes in human right- vs. left-sided endocarditis. To study this in vivo, 90 rabbits with tricuspid Pseudomonas aeruginosa endocarditis received either no therapy (controls), nitrogen mustard (HN2) to induce combined granulocytopenia + monocytopenia, etoposide (VP-16-213) to induce selective monocytopenia, or dexamethasone. Intravegetation inflammatory cell influxes were scored on a semiquantitative histopathologic scale. In VP-16-213 and dexamethasone recipients and tricuspid endocarditis controls, gradual decreases in mean intravegetation bacterial densities were observed over a 13-day infection period; in contrast, HN2 treatment was associated with a significant increase in intravegetation bacterial densities by day 13 of infection (p less than 0.001 vs. other tricuspid endocarditis groups). Histopathologically, vegetations from untreated controls and dexamethasone recipients showed granulocyte influxes during infection, while HN2 treatment resulted in predominantly granulocyte depletion within infected tricuspid vegetations; VP-16-213 caused mononuclear cell depletion at this site. This study supports the concept that the granulocyte plays a critical role in modulating spontaneous endocardial clearances of bacteria in experimental tricuspid endocarditis. 相似文献
10.
Development of beta-lactam resistance and increased quinolone MICs during therapy of experimental Pseudomonas aeruginosa endocarditis. 下载免费PDF全文
The in vivo efficacies of pefloxacin, a new fluoroquinolone, and amikacin-ceftazidime were compared in 50 rabbits with experimental aortic endocarditis caused by Pseudomonas aeruginosa. Animals were randomly chosen to receive 4 or 10 days of no therapy (controls), pefloxacin (40 mg/kg [body weight] per day, intramuscularly [i.m.]), or amikacin (30 or 80 mg/kg per day, i.m.)-ceftazidime (150 mg/kg per day, i.m.). Pefloxacin and both amikacin regimens significantly reduced vegetation bacterial densities compared with controls at days 4 and 10 of treatment (P less than 0.0005). By day 10 of therapy, between 33 and 40% of vegetations from amikacin-ceftazidime recipients contained ceftazidime-resistant bacteria (MICs, greater than 25 micrograms/ml); nitrocefin agar overlay confirmed that these ceftazidime-resistant variants were constitutive overproducers of beta-lactamase. At therapy days 4 and 10, approximately 30% of vegetations sampled from pefloxacin recipients contained bacteria for which pefloxacin MICs were four- to eightfold higher than the MIC for the parental strain used to initially induce endocarditis (MIC, 0.19 microgram/ml). These variants also exhibited increases in ciprofloxacin and ticarcillin MICs, as well as pleotropic resistance to chloramphenicol (but not to amikacin, ceftazidime, or tetracycline). Amikacin-ceftazidime, as well as pefloxacin, was effective in this model of aortic pseudomonal endocarditis. However, in vivo development of ceftazidime resistance and step-ups in pefloxacin MICs among intravegetation isolates were associated with inability to completely eradicate P. aeruginosa from aortic vegetations. 相似文献