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991.
BACKGROUND: An abnormal IgLkappa:IgLlambda ratio has long been used as a clinical criterion for non-Hodgkin B-cell lymphomas. As a first step toward a quantitative real-time PCR-based multimarker diagnostic analysis of lymphomas, we have developed a method for determination of IgLkappa:IgLlambda ratio in clinical samples. METHODS: Light-up probe-based real-time PCR was used to quantify IgLkappa and IgLlambda cDNA from 32 clinical samples. The samples were also investigated by routine immunohistochemical analysis and flow cytometry. RESULTS: Of 32 suspected non-Hodgkin lymphoma samples analyzed, 28 were correctly assigned from real-time PCR measurements assuming invariant PCR efficiencies in the biological samples. Four samples were false negatives. One was a T-cell lymphoma, one was a diffuse large B-cell lymphoma, and one was reanalyzed and found lymphoma-positive by in situ calibration, which takes into account sample-specific PCR inhibition. Twelve of the samples were fine-needle aspirates, and these were all correctly assigned. CONCLUSIONS: This work is a first step toward analyzing clinical samples by quantitative light-up probe-based real-time PCR. Quantitative real-time PCR appears suitable for high-throughput testing of cancers by measuring expression of tumor markers in fine-needle aspirates. 相似文献
992.
Delaying defibrillation to give basic cardiopulmonary resuscitation to patients with out-of-hospital ventricular fibrillation: a randomized trial 总被引:20,自引:0,他引:20
Context Defibrillation as soon as possible is standard treatment for patients with ventricular fibrillation. A nonrandomized study indicates that after a few minutes of ventricular fibrillation, delaying defibrillation to give cardiopulmonary resuscitation (CPR) first might improve the outcome. Objective To determine the effects of CPR before defibrillation on outcome in patients with ventricular fibrillation and with response times either up to or longer than 5 minutes. Design, Setting, and Patients Randomized trial of 200 patients with out-of-hospital ventricular fibrillation in Oslo, Norway, between June 1998 and May 2001. Patients received either standard care with immediate defibrillation (n = 96) or CPR first with 3 minutes of basic CPR by ambulance personnel prior to defibrillation (n = 104). If initial defibrillation was unsuccessful, the standard group received 1 minute of CPR before additional defibrillation attempts compared with 3 minutes in the CPR first group. Main Outcome Measure Primary end point was survival to hospital discharge. Secondary end points were hospital admission with return of spontaneous circulation (ROSC), 1-year survival, and neurological outcome. A prespecified analysis examined subgroups with response times either up to or longer than 5 minutes. Results In the standard group, 14 (15%) of 96 patients survived to hospital discharge vs 23 (22%) of 104 in the CPR first group (P = .17). There were no differences in ROSC rates between the standard group (56% [58/104]) and the CPR first group (46% [44/96]; P = .16); or in 1-year survival (20% [21/104] and 15% [14/96], respectively; P = .30). In subgroup analysis for patients with ambulance response times of either up to 5 minutes or shorter, there were no differences in any outcome variables between the CPR first group (n = 40) and the standard group (n = 41). For patients with response intervals of longer than 5 minutes, more patients achieved ROSC in the CPR first group (58% [37/64]) compared with the standard group (38% [21/55]; odds ratio [OR], 2.22; 95% confidence interval [CI], 1.06-4.63; P = .04); survival to hospital discharge (22% [14/64] vs 4% [2/55]; OR, 7.42; 95% CI, 1.61-34.3; P = .006); and 1-year survival (20% [13/64] vs 4% [2/55]; OR, 6.76; 95% CI, 1.42-31.4; P = .01). Thirty-three (89%) of 37 patients who survived to hospital discharge had no or minor reductions in neurological status with no difference between the groups. Conclusions Compared with standard care for ventricular fibrillation, CPR first prior to defibrillation offered no advantage in improving outcomes for this entire study population or for patients with ambulance response times shorter than 5 minutes. However, the patients with ventricular fibrillation and ambulance response intervals longer than 5 minutes had better outcomes with CPR first before defibrillation was attempted. These results require confirmation in additional randomized trials. 相似文献
993.
994.
Rønold HJ Lyngstadaas SP Ellingsen JE 《Journal of biomedical materials research. Part A》2003,67(2):524-530
In the present study, the effect of a dual treatment of titanium implants and the subsequent bone response after implantation were investigated. Coin-shaped c.p. titanium implants were placed into the tibias of 12 rabbits. The implant, which was dually blasted with TiO2 particles of two different sizes, was compared with implants that were blasted with only one of these particle sizes. Implants in group 1 were grit blasted with small particles, 22-28 microm in size, and group 2 with coarser particles, 180-220 microm size. These two treatments gave different surface micro textures. To test the effect of a combination of two different treatments, group 3 implants were blasted first with the 180- to 220-microm and subsequently with the 22- to 28-microm particles. The surface topography of the implant specimens was examined by scanning electron microscopy and by a confocal laser scanner and a numeric evaluation of S(a), S(t), and S(dr) was recorded. Group 2 implants, which were blasted with only the coarse particles, showed a significantly better functional attachment (p < 0.001) than the other two groups. Group 1, which was blasted with only small particles, showed the lowest retention in bone. There was a positive correlation between the topographical and mechanical evaluation of the surfaces. 相似文献
995.
Brandtzaeg P 《Expert review of anti-infective therapy》2003,1(4):589-596
Plasma levels of lipopolysaccharides are closely associated with disease manifestations and outcomes in meningococcal infections. The knockout mutant lpxA-Neisseria meningitidis completely lacking lipopolysaccharides has made it possible to study the contribution of nonlipopolysaccharide molecules in the bacterial cell wall to the host's response. The lpxA-N. meningitidis requires 10- to 100-fold higher concentrations of bacteria to elicit the same level of pro-inflammatory cytokines (tumor necrosis factor-alpha, interleukin-1beta and -6) as the wild type parent strain. It activates human mononuclear peripheral blood cells through CD14 and Toll-like receptor-2 receptor complex whereas the wild type strain activates these cells through the CD14-Toll-like receptor-4-MD2 pathway. Dendritic cells are hardly activated by the lpxA-N. meningitidis. It is as efficient as the wild type strain in activating complement. The lpxA-N. meningitidis expresses pili but does not adhere or invade mucosal cells normally. The defensin-mediated adhesion of lpxA-N. meningitidis to the respiratory epithelial cells is severely reduced as compared with the wild-type strain. 相似文献
996.
Advanced life support therapy on out-of-hospital cardiac arrest patients: an engineering perspective
In the USA alone, several hundred thousand people die of sudden cardiac arrests each year. Basic life support, defined as chest compressions and ventilations, and early defibrillation are the only factors proven to increase the survival of patients with out-of-hospital cardiac arrest and are key elements in the chain of survival defined by the American Heart Association. The current cardiopulmonary resuscitation guidelines treat all patients the same but studies show a need for more individualization of treatment. This review focusses on ideas on how to strengthen the weak parts of the chain of survival including the ability to measure the effects of therapy, improve time efficiency and optimize the sequence and quality of the various components of cardiopulmonary resuscitation. 相似文献
997.
Exact Pearson's chi square, likelihood ratio (LR), and Fisher's tests are obtained from the conditional distribution of its test statistic, given the row and column sums of the contingency table. The power and obtained significance level of the standard, mid p, and randomized versions of these tests are compared for two-sided tests in 2 x 2 tables, using binomial and multinomial sampling. The mid p type I error probabilities seldom exceed the nominal significance level. The mid p and randomized test versions have approximately the same power, and higher power than the standard test version. The power of the Pearson's chi square, LR and Fisher's test differ, and they differ in approximately the same way for standard, mid p and randomized test versions for any given set of parameters. There is no general ranking between the three tests. In many cases, Pearson's chi square and Fisher's tests have almost equal power, and higher power than LR. In a few cases, perhaps characterized by poorly balanced designs, LR performs best. Fisher's test seems to be slightly more robust even if the design is poor. 相似文献
998.
Partial outlet obstruction enhances modular autonomous activity in the isolated rat bladder 总被引:4,自引:0,他引:4
Drake MJ Hedlund P Harvey IJ Pandita RK Andersson KE Gillespie JI 《The Journal of urology》2003,170(1):276-279
PURPOSE: Autonomous bladder activity can take the form of localized micromotions (MMs), suggesting that the detrusor may be arranged into component modules, of which each is capable of contracting autonomously. We examined MMs in isolated whole rat bladder and the effects of partial bladder outlet obstruction as a model of detrusor overactivity (DO) to ascertain whether altered modular activity could be an etiological factor in DO. MATERIALS AND METHODS: A total of 12 adult female Sprague-Dawley rats underwent obstruction or sham operation for 1 or 4 weeks. Bladders were microsurgically removed and mounted in whole organ tissue baths. Recordings of intravesical pressure and simultaneous registration of intramural contractions were performed under standardized conditions. RESULTS: Prior to filling MMs took the form of localized contractions near the vesicoureteral junction in sham operated animals and multifocal microcontractions in obstructed animals. Intravesical volume increases were associated with a change in localized MMs to propagated contraction waves. In sham operated animals stretch resulted in increased MM frequency but decreased amplitude. After obstruction stretch elicited highly coordinated MMs and enhanced intravesical pressure transmission. The time since surgery did not alter observations in the sham or obstructed group. CONCLUSIONS: Detrusor muscle in isolated bladders under conditions modeling urine storage may have a functional modular arrangement with the basolateral region most active prior to filling. Peripheral factors determining intravesical pressure include the number of modules active, coordination and intramural tension at other sites. After bladder outlet obstruction more modules are active at baseline and their coordination is enhanced by stretch, leading to increased pressure fluctuations. Such changes may contribute to the development of DO. 相似文献
999.
Peloponissios N Halkic N Pugnale M Jornod P Nordback P Meyer A Gillet M 《Archives of surgery (Chicago, Ill. : 1960)》2003,138(12):1367-1370
BACKGROUND: Hepatic portal venous gas (HPVG) in adults is a rare entity. The underlying pathologic condition is usually an intestinal ischemia, but it has been reported in association with a variety of conditions. HYPOTHESIS: Miscomprehension of the underlying pathologic conditions has led to some confusion in the literature concerning its etiology, diagnostic methods, and clinical consequences. SETTING: Centre Hospitalier et Universitaire Vaudois, Lausanne, Switzerland, and District Hospital of Morges, Morges, Switzerland. METHOD: Between February 1, 1995, and May 30, 2000, eleven cases of HPVG were treated. These cases were retrospectively reviewed, together with a review of the literature to define the clinical significance of HPVG, the role of the computed tomographic scan, and the necessity of performing systematic emergency exploratory surgery. RESULTS: Two groups have to be distinguished-those who have HPVG with associated pneumatosis intestinalis and those who have HPVG without associated pneumatosis intestinalis. When associated with pneumatosis intestinalis, the cause is usually an intestinal ischemia and in a symptomatic patient it justifies systematic exploratory surgery. An abdominal computed tomographic scan including lung window settings to better identify air in the bowel wall will distinguish between these 2 groups. Pneumatosis intestinalis and HPVG due to bowel ischemia do not allow prediction of the severity of bowel wall damage. CONCLUSIONS: The cause of HPVG without pneumatosis intestinalis is variable. Good knowledge of the possible causes combined with the clinical picture and the abdominal computed tomographic scan is required to correctly identify the underlying cause of HPVG and to avoid unnecessary surgery. 相似文献
1000.