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91.
Background. Literature spanning the last two decades has identified potential harm associated with out-of-hospital endotracheal intubation performed by ground paramedics. Previous researchers have reported intubation success rates of 66% to 97% in the air medical setting. Objective. To examine the success of endotracheal intubation and rescue techniques performed by air medical personnel during the first eight years of operation of the air ambulance service. Methods. This study was a retrospective survey of health records utilizing data from LifeFlight of Maine's airway procedure quality review database, covering the first eight years of system encounters. Results. During the study period, 369 intubation encounters occurred. Rapid-sequence intubation medications were administered in 345 (93.5%) cases. Flight personnel successfully performed endotracheal intubation in 340 (92.1%) encounters. Unsuccessful intubations were managed with an alternative definitive airway, rescue airway, or bag–valve–mask. Laryngeal mask airway (n = 11) was the most commonly used rescue airway device. Conclusions. During the first eight years of operation of this air medical transport system, flight personnel were able to successfully perform endotracheal intubation in 92.1% of cases.  相似文献   
92.

Background

Emergency physicians are increasingly performing transvaginal ultrasound (TVUS) to rule out ectopic pregnancy. However, little is known about appropriate educational pathways to train emergency medicine residents in TVUS.

Study Objectives

To evaluate the ability of Emergency Medicine (EM) residents who underwent a training program in TVUS to detect the presence or absence of an intrauterine pregnancy (IUP) in patients of < 13 weeks gestation with vaginal bleeding or abdominal pain, as compared to the final interpretation of each study as determined by the Emergency Department (ED) Director of Ultrasound.

Methods

This was a prospective, observational study in a single residency program. Training included a lecture, competency examination, and 10 supervised TVUSs. The EM residents then performed TVUSs with the goal of determining the presence or absence of an IUP without input from an attending physician. Correlation with the ED Director of Ultrasound was assessed for the cohort, and stratified by year of training. Results: There were 22 residents who performed 75 TVUSs over 17 months. Correlation with the ED Director of Ultrasound was 93.3%. Differences in correlation with the ED Director of Ultrasound were noted when compared by year of training: post-graduate year (PGY)-3 (93.3%), PGY-2 (92.1%), and PGY-1 (100%); p < 0.001.

Conclusion

Residents were able to perform TVUSs to determine the presence or absence of an IUP in patients in whom the diagnosis of ectopic pregnancy was being considered with a high degree of correlation with the ED Director of Ultrasound after a brief training program. Correlation with the ED director of ultrasound was influenced by year of training.  相似文献   
93.
Modulation of polymorphonuclear leukocyte function by cetiedil   总被引:1,自引:0,他引:1  
Wolach  JB; Coates  TD; Tzeng  DY; Baehner  RL; Boxer  LA 《Blood》1983,62(2):274-279
Cetiedil citrate monohydrate inhibits sickling of red cells and aggregation of platelets. We assessed its ability to attenuate polymorphonuclear leukocyte (PMN) function. PMN aggregation in response to 2 X 10(-7) M formyl-met-leu-phe (FMLP) was inhibited in a dose- dependent fashion by cetiedil concentrations ranging from 60 to 250 microM. Additionally, 125 microM cetiedil inhibited PMN aggregation in response to 2 X 10(-7) M FMLP, 20 ng/ml phorbol myristate acetate (PMA), and 1 X 10(-6) M A23187 by 69% +/- 18%, 72% +/- 20%, and 65% +/- 4%, respectively. Inhibition of FMLP-induced aggregation was provided by only 5 min of incubation of the drug with the cells and was partially reversible. Cell viability was unaffected by exposure of PMN to the drug. Correspondingly, 125 microM cetiedil prevented the translocation of calcium from the PMN membrane as assessed by chlorotetracycline fluorescence. Paralleling the effect of the drug on PMN aggregation, 125 microM cetiedil inhibited release of superoxide by 55% and decreased the number of available 3H-FMLP receptors. However, its effect on release of the primary granule constituent, myeloperoxidase, was minimal (4.5% inhibition), while the effect on release of the specific granule product, lactoferrin (27% inhibition), was modest. These studies indicate that cetiedil affects PMN aggregation and superoxide release to a much greater extent than PMN degranulation. Thus, cetiedil may have potential uses in modulating inflammatory response in vivo.  相似文献   
94.
95.
Dexter  TM; Testa  NG; Allen  TD; Rutherford  T; Scolnick  E 《Blood》1981,58(4):699-707
In long-term marrow cultures, proliferation and differentiation of hemopoietic stem cells occurs for several months. Normally, only the most primitive erythroid progenitor cells are produced (the BFU-E). Following treatment with anemic mouse serum (AMS) or normal mouse serum plus erythropoietin, the BFU-E mature into CFU-E, which then go to produce mature nonnucleated red cells. This development is associated with the production of adult type hemoglobin. Furthermore, erythropoiesis and granulopoiesis occur in association with discrete cellular elements of the adherent cell layer in the long-term culture. Following treatment with AMS, erythropoiesis is enhanced while granulopoiesis is depressed, with no apparent competition at the stem cell or progenitor cell level.  相似文献   
96.
97.
98.
Imprinting of mouse Kvlqt1 is developmentally regulated   总被引:4,自引:1,他引:4  
  相似文献   
99.
The frequency of thioguanine(TG)-resistant lymphocytes in mice treated with ethylnitrosourea (ENU) was followed for a period of 51 wk using our clonogenic assay [Jones et al, 1985a,b]. The effects of dose (0-58 mg/kg), time since treatment (2-51 wk), dose rate (5 weekly X 11.7 mg/kg versus 1 X 58 mg/kg), and age at time of treatment (3 vs 15 mo) on the frequency of TG-resistant, concanavalin A-responsive spleen cells were evaluated. The frequencies of TG-resistant spleen cells were generally dose responsive for 51 wk after exposure to ENU. They also were dependent upon the time that had elapsed since treatment with ENU, increasing to maximal values at 10 wk as previously reported [Jones et al, 1985a], and holding essentially stable at values of approximately 20% of the maximum frequency from week 15 until at least week 40 for the 3-month-old mice. Fractionation of 58 mg ENU/kg into 5 weekly doses did not affect the frequency of ENU-induced TG-resistant cells detected in the spleen but did increase the rate of appearance in the spleen, and the efficiency of induction by the unit dose, of TG-resistant cells. The mice exposed to ENU at 15 mo of age appeared to have a 4-fold reduction in the rate of increase in frequency of ENU-induced TG-resistant spleen cells. One set of control mice was found to have a 10-fold elevated frequency of TG-resistant cells in both the spleen and thymus, indicating that mutations can occur in stem cells of untreated animals.  相似文献   
100.
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