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961.
DF Willson A Zaritsky LA Bauman K Dockery RL James D Conrad H Craft WE Novotny EA Egan H Dalton 《Canadian Metallurgical Quarterly》1999,27(1):188-195
OBJECTIVE: Prospective study of the efficacy of calf lung surfactant extract in pediatric respiratory failure. DESIGN: Multi-institutional, prospective, randomized, controlled, unblinded trial. SETTING: Eight pediatric intensive care units (ICU) of tertiary medical centers. PATIENTS: Forty-two children with acute hypoxemic respiratory failure characterized by diffuse, bilateral pulmonary infiltrates, need for ventilatory support, and an oxygenation index of >7. INTERVENTION: Instillation of intratracheal surfactant (80 mL/m2). MEASUREMENTS AND MAIN RESULTS: Ventilator parameters, arterial blood gases, and derived oxygenation and ventilation indices were recorded before and at intervals after surfactant administration. Complications and outcome measures, including mortality, duration of mechanical ventilation, and length of pediatric ICU and hospital stay, were also examined. Patients who received surfactant demonstrated rapid improvement in oxygenation and, on average, were extubated 4.2 days (32%) sooner and spent 5 fewer days (30%) in pediatric intensive care than control patients. There was no difference in mortality or overall hospital stay. Surfactant administration was associated with no serious adverse effects. CONCLUSIONS: Administration of calf lung surfactant extract, calfactant, appears to be safe and is associated with rapid improvement in oxygenation, earlier extubation, and decreased requirement for intensive care in children with acute hypoxemic respiratory failure. Further study is needed, however, before widespread use in pediatric respiratory failure can be recommended. 相似文献
962.
Effects of test conditions on the outcome of place conditioning with morphine and naltrexone in mice
AY Bespalov ME Tokarz SE Bowen RL Balster PM Beardsley 《Canadian Metallurgical Quarterly》1999,141(2):118-122
BACKGROUND: Although it is widely proposed that surgeons, before introducing a novel laparoscopic technique in man, should practice in an appropriate animal model for acquisition of the necessary technical skills, the effectiveness of those hands-on training courses are rarely documented. METHODS: In 1995 we have organized eight hands-on training courses for laparoscopic anterior interbody spine fusion in an in vivo porcine model. A total of 72 colleagues from 50 different centers of 12 countries participated, including orthopedic, trauma, visceral, neuro-, and vascular surgeons. Quality and effectiveness of the course were evaluated by a questionnaire after a 1.5- to 2.5-year period. RESULTS: During this time, 42.2% of the participating centers had applied the new technique successfully in man. Centers which participated in the course with a team that included a skilled laparoscopic surgeon and an orthopedic or trauma surgeon introduced the technique more frequently to clinical practice (57.9%) than those represented by only one participant (30. 8%). Moreover, there was a tendency toward a more frequent introduction of the technique to clinical practice in centers associated with university hospitals (57.1% vs. 29.2%), indicating the requirement of a particular infrastructure for this complex interdisciplinary procedure. Almost all participants (98.3%) agreed that for novel surgical techniques requiring advanced technical skills, there should first be training in a large animal model before the technique is applied in man. CONCLUSIONS: Complex laparoscopic procedures (i.e., laparoscopic spine surgery) can be successfully learned by in vivo hands-on training courses. We propose that for refinements and modifications of the technique (e.g. , the lumboscopic approach), there should also first be training in a large animal model before these are applied in man. 相似文献
963.
C.B-17 scid mice, which were found to be very susceptible to infection with Leishmania major, were reconstituted with various doses of T cells, T plus B cells or unfractionated spleen cells from nonhealer BALB/c mice. All reconstitution protocols, except for the transfer of very high numbers of BALB/c spleen cells, led to a spontaneously healing infection and resistance to reinfection, rather than the lethal, nonhealing infection typical of BALB/c mice. These healing responses were associated with a strong T helper 1 (Th1)-like response characterized by delayed-type hypersensitivity (DTH) responsiveness, but no elevation of serum IgE, and by the production of high levels of interferon-gamma (IFN-gamma), but no interleukin-4 (IL-4) by lymph node and spleen cells after restimulation with antigen in vitro. The development of this Th1 response from BALB/c Th cells requires IFN-gamma during the initial infection period. Treatment of scid mice with a single injection of neutralizing anti-IFN-gamma antibody prior to infection and reconstitution prevented healing and permitted the development of a Th-2 like response as indicated by elevated serum IgE, but no DTH, and by the production of IL-4, but very little IFN-gamma, after antigen stimulation in vitro. As few as 10(4) transferred T cells led to a Th1-like response, suggesting that the IFN-gamma is of host rather than donor origin. The transfer of very high numbers (7.5 x 10(7)) of BALB/c spleen cells overcame the effects of the IFN-gamma and led to the nonhealing infection and cytokine pattern characteristic of BALB/c mice. The enrichment or depletion of B cells from the transferred T cells had no measurable effect upon the development of a healing response in reconstituted scid mice. 相似文献
964.
AIMS: (1) To examine the matching hypothesis that Twelve Step Facilitation Therapy (TSF) is more effective than Motivational Enhancement Therapy (MET) for alcohol-dependent clients with networks highly supportive of drinking 3 years following treatment; (2) to test a causal chain providing the rationale for this effect. DESIGN: Outpatients were re-interviewed 3 years following treatment. ANCOVAs tested the matching hypothesis. SETTING: Outpatients from five clinical research units distributed across the United States. Participants: Eight hundred and six alcohol-dependent clients. INTERVENTION: Clients were randomly assigned to one of three 12-week, manually-guided, individual treatments: TSF, MET or Cognitive Behavioral Coping Skills Therapy (CBT). MEASUREMENTS: Network support for drinking prior to treatment, Alcoholics Anonymous (AA) involvement during and following treatment, percentage of days abstinent and drinks per drinking day during months 37-39. FINDINGS: (1) The a priori matching hypothesis that TSF is more effective than MET for clients with networks supportive of drinking was supported at the 3 year follow-up; (2) AA involvement was a partial mediator of this effect; clients with networks supportive of drinking assigned to TSF were more likely to be involved in AA; AA involvement was associated with better 3-year drinking outcomes for such clients. CONCLUSIONS: (1) In the long-term TSF may be the treatment of choice for alcohol-dependent clients with networks supportive of drinking; (2) involvement in AA should be given special consideration for clients with networks supportive of drinking, irrespective of the therapy they will receive. 相似文献
965.
T Koizumi K Kubo M Hanaoka T Miyahara T Kaneki H Yamamoto RL Ge K Fujimoto T Kobayashi M Sekiguchi 《Canadian Metallurgical Quarterly》1998,48(11):1097-1100
7-Ethyl-10-[4-(1-piperidino)-1-piperidino]-carbonyloxycamptothecin (CPT-11, 100286-90-6) is one of the most promising novel anticancer agents, especially for lung cancer. 7-Ethyl-10-hydroxycamptothecin (SN-38), an active metabolic of CPT-11, has much stronger cytotoxicity than CPT-11. The present study was designed to evaluate the distribution and behavior of CPT-11 and SN-38 in lung lymph circulation following intravenous infusion. Awake sheep with chronically instrumented lung lymph fistulas were prepared. The concentrations of CPT-11 and SN-38 in plasma and lung lymph fluid were measured after intravenous infusion of 100 mg/body of CPT-11 for 90 min. SN-38 constantly showed higher lymph to plasma concentration ratios than those of CPT-11, and the % area under the curve (AUC) ratio of SN-38/CPT-11 in lymph fluid was significantly higher than that in plasma. These data indicated that SN-38 distributed in lung tissue moved more easily into lung lymph fluid than CPT-11, and might be more rapidly metabolized in lung tissue than plasma. CPT-11 may have favorable therapeutic effects on intrathoracic malignancies such as lung cancer and lymph metastasis. 相似文献
966.
RL Jansen PS Hupperets JW Arends SR Joosten-Achjanie A Volovics HC Schouten HF Hillen 《Canadian Metallurgical Quarterly》1998,78(4):460-465
The proliferative activity of a tumour is considered to be an important prognostic factor in primary breast cancer. We have investigated the prognostic value of the MIB-1 labelling index in 341 patients with primary breast cancer and compared the results with the S-phase fraction in 220 patients of the same cohort. All patients were treated in one hospital and had a median follow-up of 128 months. No correlation between MIB-1 labelling and S-phase fraction could be demonstrated. MIB-1 had prognostic value for disease-free survival in the whole group of patients (P < 0.001) and in the node-negative subgroup (P < 0.001). In multivariate analysis, MIB-1 was an independent prognostic factor (P = 0.004) besides axillary lymph node status (P = 0.001). In univariate analysis high S-phase fraction was associated with decreased overall survival (P = 0.04); however, not in multivariate analysis. Moreover, S-phase fraction had a borderline prognostic significance for post-relapse survival in multivariate analysis (P= 0.08). Thus, in conclusion, the growth fraction of a tumour as determined by the MIB-1 labelling index is an important prognostic factor in patients with primary breast cancer. 相似文献
967.
JA Peterson M Hamosh CD Scallan RL Ceriani TR Henderson NR Mehta M Armand P Hamosh 《Canadian Metallurgical Quarterly》1998,44(4):499-506
The change of brain lesion load, measured on T2-weighted magnetic resonance imaging (MRI) using computer-assisted techniques, is a widely used secondary endpoint for phase III clinical trials in multiple sclerosis (MS). Collection, transfer, and analysis of the electronic data across multiple centers have all proved challenging and give rise to potential errors. However, many new acquisition schemes and postprocessing techniques have been developed; these may reduce scan times and result in better lesion conspicuity or lessen the human interaction needed for data analysis. This review considers many aspects of the use of MRI in clinical trials for MS and provides international consensus guidelines, derived from a task force of the European Magnetic Resonance Networks in Multiple Sclerosis (MAGNIMS) together with a group of North American experts. The main points considered are the organization of correctly powered trials and selection of participating sites; the appropriate choice of pulse sequences and image acquisition protocol given the current state of technology; quality assurance for data acquisition and analysis; accuracy and reproducibility of lesion load assessments; and the potential for the application of quantitative methods to other MRI-derived measures of disease burden. 相似文献
968.
I Mavromichalis DM Webel JL Emmert RL Moser DH Baker 《Canadian Metallurgical Quarterly》1998,76(11):2833-2837
Three trials were carried out with pigs between 5 and 8 wk of age to determine the limiting order of amino acids in a 13.5% CP corn-soybean meal-based diet containing 8% dried whey. The positive-control diet was a 19.2% CP corn-soybean meal-based diet (1.15% lysine), also with 8% dried whey. Amino acid additions to the low-protein, negative-control diet were based on levels needed to accomplish 110% of ideal ratios (to lysine, set at 1.15%). In Exp. 1, the addition of an amino acid mixture containing Lys, Trp, Thr, Met, Ile, and Val to the low-protein diet increased (P<.05) gain and gain: feed ratio, and these response traits were not different from those of pigs fed the 19.2% CP positive-control diet. Single deletion of Lys from the supplemental amino acid mixture depressed performance to a greater (P<.05) extent than single deletion of any of the other amino acids. Single deletions of Trp, Thr, Met, or Val decreased (P<.05) performance in a similar but lesser magnitude than the decrease caused by Lys deletion, whereas Ile deletion was without effect. Experiments 2 and 3 were designed to evaluate the limiting order of AA beyond Lys in the low-protein diet. Neither His nor Glu were found to be deficient, and, as in Exp. 1, deletion of Trp, Thr, Met, or Val from the supplemental amino acid mixture resulted in performance depressions (P<.05) that were similar. The results suggest that Lys is first-limiting and Trp, Thr, Met, and Val are equally second-limiting in a reduced protein (13.5% CP) corn-soybean meal-based diet with 8% whey for 10-kg pigs. 相似文献
969.
Dermal penetration of chemicals and drugs is of concern to both toxicologists and pharmacologists. Environmental professionals try to limit exposure to chemicals using protective clothing and gloves or barrier creams to trap chemicals. Drug developers try to enhance penetration of chemicals through the skin for medical purposes. Both can use predictive biologically-based mathematical models to assist in understanding the processes involved. These models are especially useful when they are based on physiological and biochemical parameters which can be measured in the laboratory. Appropriately validated models based on conservation of mass, diffusion and chemical transport by flow can be predictive of human exposures. In this paper we develop two new physiologically-based pharmacokinetic (PBPK) skin models to predict blood concentrations of dibromomethane in rats after skin-only vapor exposures. These new models improve the predictions of the blood concentrations especially at the beginning of the exposures. Sensitivity analysis shows that the permeability constants followed by partition coefficients have the most impact on blood concentration predictions. With proper validation the new models could be used to improve species, dose, and duration extrapolations of chemical or drug penetration. They could also be used to investigate and predict concentrations of drugs or chemicals in the skin. 相似文献
970.