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1.
Dr Arthur J. L. Schneider MD W. Bosseau Murray MBChB MD Steven C. Mentzer BS Fernando Miranda BS Sorin Vaduva MS 《Journal of clinical monitoring and computing》1995,11(6):358-364
Objective. The medical practitioner is faced with an increasing list of protocols and algorithms related to patient care. These recommendations are often difficult to recall, particularly in stressful emergency situations. Using advanced cardiac life support (ACLS) protocols, we built a computer-based system to exhibit precompiled response plans for medical emergencies. To validate the usefulness of this prompting device, we tested application of two of the nine ACLS algorithms, pulseless ventricular fibrillation/ventricular tachycardia (Vfib/Vtach) and bradycardia, in a simulated operating room (OR) environment.Methods. The system utilized the software authoring system IconAuthor (Aimtec Inc., Nashua, NH) and a touch-screen monitor (DiamondScan, Microtouch, Methuen, MA). Prior to testing our system, all 39 subjects were given time to familiarize themselves with its operation. Subsequently, all subjects were videotaped while managing a standard simulated anesthetic. During the anesthetic, the subjects were presented with two emergency scenarios, not viewed during the familiarization period. The electrocardiographic (EKG) signals for normal sinus rhythm, ventricular fibrillation, and second-degree heart block were presented. By random selection, the prompter was available to half of the subjects for help with arrhythmia management (experimental group), while to half it was not (control group).Results. A total of 39 subjects completed the exercise. Use of the prompter enabled significantly more subjects to administer correct drugs and dosages during ventricular fibrillation. The correct lidocaine dose was chosen more often by the experimental group than by the control (p=0.015); similarly MgSO4 was appropriately ordered more often in the experimental group (p=0.003). During second-degree heart block, atropine was correctly followed with a dopamine infusion (p=0.004), and epinephrine infusion was ordered for refractory bradycardia (p=0.002) more often in the experimental than the control group.Conclusions. These data demonstrate the value of a prompting device at the anesthesia workstation. We foresee the use of such prompters in many areas of medicine.This study was made possible by a grant from the Anesthesia Patient Safety Foundation. Results were presented, in part, at the meeting of the STA/SEA Orlando, Florida, January 1994. 相似文献
2.
Sorin Blendea Kort Eckman Branislav Jaramaz Timothy J Levison Anthony M Digioia 《Computer aided surgery》2005,10(1):37-43
This study presents a clinical validation of postoperative measurements of acetabular cup alignment following total hip arthroplasty (THA). The methodology was based on concurrent anatomic three-dimensional (3D) measurements of both the acetabular cup alignment and pelvic orientation, using an original CT/X-ray matching algorithm named Xalign. The subjects were 19 patients who had undergone bilateral THA using CT-based surgical navigation. All patients had postoperative pelvic CT scans and multiple antero-posterior (AP) pelvic X-rays. Using a proprietary software algorithm, the X-rays included in the study were matched with the corresponding postoperative CT scans. The goal of this method was to allow 3D anatomic pelvic and acetabular measurements on two-dimensional AP X-rays. The postoperative cup abduction, version and pelvic flexion angles were determined in three different ways: using CT images directly, applying the Xalign method, and finally by performing conventional (abduction only) measurements on AP pelvic X-rays. The cup orientation measured on CT images was taken as the ground truth. The Xalign measurement errors were defined as the difference between the CT cup values and those obtained by applying the matching method. The mean cup abduction error was 0.85 degrees +/- 1.3 degrees (+/- standard deviation) and the mean version error was 0.01 degrees +/- 1.99 degrees . Conventionally measured cup abduction ranged from 44 degrees to 62 degrees and correlated significantly (p = 0.001, r = -0.5) with pelvic flexion angle, proving the linear negative correlation between pelvic flexion and the error in conventional radiographic cup measurements. The Xalign method offered reasonable accuracy for cup orientation, and allowed cup and pelvic 3D anatomic measurements at different times. 相似文献
3.
F Gerald R Fowkes Lip-Ping Low Sorin Tuta Joseph Kozak 《European heart journal》2006,27(15):1861-1867
AIMS: AGATHA (a Global Atherothrombosis Assessment) was designed to assess the extent of atherothrombosis and the use of the ankle-brachial index (ABI) in vascular patients. The principal hypotheses were that (1) in diseased patients, a low ABI was related to the number and site of vascular beds affected and (2) in at-risk patients without disease, a low ABI was related to the number of risk factors present. METHODS AND RESULTS: Patients were recruited consecutively by 482 clinicians in 24 countries and the ABI measurement was performed at a single visit. Of 8891 patients recruited, 1792 were defined as at risk and 7099 as with disease. Of the with-disease patients, 65.2% had one arterial bed affected, 27.6% two and 7.1% all three. Abnormal ABI (< or =0.9) was present in 30.9% of at-risk and 40.5% of with-disease patients. A lower ABI was weakly associated with an increasing number of risk factors in at-risk patients (r=-0.056, P=0.02) and with the site and number of arterial beds affected in with-disease patients (P<0.001). CONCLUSION: This large international study confirms that atherothrombotic disease often occurs at more than one site. The ABI is related to the risk factor profile and to the site and extent of atherothrombosis. 相似文献
4.
Graham C Scanlon Mark S Wallace J Sorin Ispirescu Gery Schulteis 《Journal of investigative medicine》2006,54(5):238-244
BACKGROUND: Intradermal capsaicin is a human pain model that produces reliable pain and sensitization. This model facilitates controlled testing of analgesic efficacy via a crossover design while minimizing confounding variables in clinical pain states and retaining sufficient power with small samples. METHODS: To determine the lowest dose of capsaicin that produces consistent neurosensory measures, we administered 0.1, 1, 10, or 100 microg to healthy volunteers in a blinded manner (N = 19). Pain scores were recorded at 0, 5, 10, 15, and 60 minutes on a visual analog scale from 0 to 100. Areas and intensities of mechanical allodynia (foam brush stimulus) and pinprick hyperalgesia (von Frey test) were quantified at 15 and 60 minutes, as were flare areas. RESULTS: Capsaicin produced dose-dependent increases in spontaneous pain (p = .013), the area and intensity of mechanical allodynia (p = .006 and p < .001, respectively), the area and intensity of pinprick hyperalgesia (p = .010 and p = .014, respectively), and the flare area (p = .010). The 10 microg dose produced greater spontaneous pain than the 1 microg dose (p = .017). The 100 microg dose produced greater spontaneous pain than the 10 microg, but the difference was not statistically significant. CONCLUSION: The 10 and 100 microg capsaicin doses produced robust pain measures across a range of modalities, and lower doses produced minimal effects. Whereas most studies use 100 microg, using a lower dose is reasonable and may facilitate detection of subtle analgesic effects--particularly with nonopioid analgesics--and drugs can be tested in lower doses, minimizing adverse side effects. 相似文献
5.
This paper discusses some consequences of the discovery that antigen receptors are degenerate: Immune specificity, in contrast to the tenets of the clonal selection paradigm, must be generated by the immune response down-stream of initial antigen recognition; and specificity is a property of a collective of cells and not of single clones. 相似文献
6.
Pelisek J Engelmann MG Golda A Fuchs A Armeanu S Shimizu M Mekkaoui C Rolland PH Nikol S 《Journal of molecular medicine (Berlin, Germany)》2002,80(11):724-736
Cationic liposomes/DNA complexes are widely used vectors for delivering genes in clinical and experimental trials. Relatively low transfer efficiencies in vivo compared with viral gene transfer may be improved using local application. In addition, markedly increased transfer efficiency may be achieved in vitro and in vivo via optimization of known variables influencing liposomal transfection. Lipofection under different conditions was performed in various cell lines and primary porcine smooth muscle cells. Optimized conditions found in vitro were verified in vivo using a porcine restenosis model. Toxicity was monitored analyzing cell metabolism. Transfer efficiency and safety were determined using morphometry, histology, galactosidase assays, PCR, and RT-PCR. The most important variables enabling maximum transfer efficiency were firstly the appropriate selection of cationic lipids for the cell type to be transfected, secondly the DNA/liposome ratio chosen, which depended on the cell type and cationic lipids used, and thirdly the state of proliferation of the targeted cells. Transfection in vivo demonstrated two- to fivefold higher transfer efficiencies when transfer conditions were extrapolated from optimization experiments in stationary cells compared with the use of conditions established in proliferating cells. Application of the therapeutic gene for cecropin using optimized transfer conditions resulted in a significantly reduced neointima formation compared with the transfection using a control gene for ss-galactosidase. Thus, in this vascular model, initial optimization of lipofection in stationary cells in culture followed by local delivery in vivo and with selection of a suitable therapeutic gene led to markedly improved transfer efficiencies, gene expression, and biological effect. Stationary cell cultures simulate more realistically the in vivo situation and may therefore represent a better model for future in vivo experiments. In addition, the advantages of liposomes are easy handling, low toxicity, and the lack of carcinogenicity or immunogenic reactions. 相似文献
7.
Stein D Kurtsman L Stier S Remnik Y Meged S Weizman A 《Journal of affective disorders》2004,82(3):335-342
BACKGROUND: The knowledge available on electroconvulsive therapy (ECT) in adolescents is largely anecdotal, or based on findings from adults. The aim of the present study is to compare the use of ECT in adolescent and adult inpatients. METHODS: We retrospectively analyzed the files of all 36 adolescent (between the ages of 13 and 19) and 57 randomly selected adult inpatients (above the age of 20) treated with ECT in a university-affiliated mental heath center in Israel between 1991 and 1997. RESULTS: Sixty one percent of the adolescents improved by the end of treatment, and 53% were not hospitalized in the subsequent year. The respective percentages among adults were 83% and 49%. Whereas most adults were treated with ECT because of schizophrenic disorders, almost half of the adolescents received ECT for affective disorders. Significantly more adolescents were treated with ECT because of acute life-endangering conditions (catatonia or severe suicidal risk). No significant adverse effects were found in both groups. LIMITATIONS: Our study is based on a retrospective chart review. The adolescent and adult groups are different in psychiatric morbidity, diagnosis and outcome, have not been assessed in a blind manner, and we have not used standardized psychometric batteries for the evaluation of ECT-related memory disturbances. CONCLUSIONS: ECT may be an effective, well-tolerated and safe procedure in both adult and adolescent inpatients. 相似文献
8.
Bernloehr C Bossow S Ungerechts G Armeanu S Neubert WJ Lauer UM Bitzer M 《Virus research》2004,99(2):193-197
Recombinant Sendai virus vectors (SeVV) have become an attractive tool for basic virological as well as for gene transfer studies. However, to (i) reduce the cellular injury induced by basic recombinant SeV vectors (encoding all six SeV genes as being present in SeV wild-type (wt) genomes) and to (ii) improve SeV vector safety, deletions of viral genes are necessary for the construction of superior SeVV generations. As a strong expression system recombinant replication-incompetent adenoviruses, coding for SeV proteins hemagglutinin-neuraminidase (HN), fusion (F), or matrix (M), were generated and successfully employed for the propagation of single gene deleted (DeltaHN, DeltaF, DeltaM) recombinant SeVV. Further investigations of the propagation procedures required for single gene deleted recombinant SeVV demonstrated (i) modifications of the cell culture medium composition as well as (ii) incubation with vitamin E as crucial steps for the enhancement of SeVV-DeltaHN, -DeltaF, or -DeltaM viral particle yield. Such optimized propagation procedures even led to a successful propagation of HN-deleted viral particles (SeVV-DeltaHN), which has not been reported before. 相似文献
9.
10.
Kenneth W Yip Joseph D Mocanu P Y Billie Au Gillian T Sleep Dolly Huang Pierre Busson Wen-Chen Yeh Ralph Gilbert Brian O'Sullivan Patrick Gullane Carlo Bastianutto Fei-Fei Liu 《Clinical cancer research》2005,11(22):8131-8144
PURPOSE: A wide variety of tumors depend on the dysregulation of Bcl-2 family proteins for survival. The resulting apoptotic block can often provide a mechanism for resistance to anticancer treatments, such as chemotherapy and radiation. This current study evaluates the efficacy of combining systemically delivered Bcl-2 phosphorothioate antisense (Bcl-2 ASO) and radiation for nasopharyngeal cancer therapy. RESULTS: Antisense uptake was unaffected by 0, 3, or 6 Gy radiation. Radiation decreased the fraction of viable C666-1 cells to 60%, with a further decrease to 40% in combination with Bcl-2 ASO. Despite a modest in vitro effect, Bcl-2 ASO alone caused the regression of established xenograft tumors in mice, extending survival by 15 days in a C666-1 and by 6 days in a C15 model. The survival times for mice treated with both Bcl-2 ASO and radiation increased by 52 days in C666-1 and by 20 days in C15 tumors. This combination resulted in a more-than-additive effect in C666-1 tumors. Less impressive gains observed in C15 tumors might be attributable to higher expression of antiapoptotic Bcl-2 family proteins and limited drug distribution in the tumor. Retreatment of C666-1 tumors with the Bcl-2 ASO-radiation combination, however, was effective, resulting in mice surviving for >80 days relative to untreated controls. CONCLUSIONS: Our results show that the Bcl-2 ASO and radiation combination is a highly potent therapy for nasopharyngeal cancer. Further examination of combination therapy with radiation and other Bcl-2 family-targeted anticancer agents in both preclinical and clinical settings is definitely warranted. 相似文献