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101.
We have examined leukaemia cells from twenty-eight patients for the presence of surface immunoglobulins by a migration-inhibition technique. Immunoglobulins were identified on the cells of fourteen out of nineteen patients with chronic lymphatic leukaemia but were not present on cells from patients with chronic myeloid leukaemia or acute leukaemia. The results obtained with the migration technique were confirmed by identification of immunoglobulins in eluates and lysates of the leukaemia cells. Serial elution and lysis studies indicated that in some cases the immunoglobulins were produced by the leukaemia cells at a low but steady rate, possibly indicating a relationship between those cells and `B' cells. In other cases the immunoglobulins were readily removed from the cells and were present only in the initial eluates from the cells, suggesting that they had been adsorbed and might possibly be specific antibody. The immunoglobulin negative chronic lymphatic leukaemia cells may be related to `T' cells, a possibility supported by a high level of phytohaemagglutinin induced transformation in one case examined by this technique. 相似文献
102.
Mild hypothermia improves survival after prolonged, traumatic hemorrhagic shock in pigs 总被引:2,自引:0,他引:2
Wu X Kochanek PM Cochran K Nozari A Henchir J Stezoski SW Wagner R Wisniewski S Tisherman SA 《The Journal of trauma》2005,59(2):291-9; discussion 299-301
INTRODUCTION: Clinical studies have demonstrated improved survival after cardiac arrest with induction of mild hypothermia (34 degrees C). Infusion of ice-cold saline seems beneficial. The American Heart Association recommends therapeutic hypothermia for comatose survivors of cardiac arrest. For hemorrhagic shock (HS), laboratory studies suggest that mild hypothermia prolongs the golden hour for resuscitation. Yet, the effects of hypothermia during HS are unclear since retrospective clinical studies suggest that hypothermia is associated with increased mortality. Using a clinically relevant, large animal model with trauma and intensive care, we tested the hypothesis that mild hypothermia, induced with intravenous cold saline (ice cold or room temperature) and surface cooling, would improve survival after HS in pigs. METHODS: Pigs were prepared under isoflurane anesthesia. After laparotomy, venous blood (75 mL/kg) was continuously withdrawn over 3 hours (no systemic heparin). At HS 35 minutes, the spleen was transected. At HS 40 minutes, pigs were divided into three groups (n = 8, each): 1) Normothermia (Norm)(38 degrees C), induced with warmed saline; 2) Mild hypothermia (34 degrees C) induced with i.v. infusion of 2 degrees C saline (Hypo-Ice) and surface cooling; and 3) Mild hypothermia (34 degrees C), induced with room temperature (24 degrees C) i.v. saline (Hypo-Rm) and surface cooling. Fluids were given when mean arterial pressure (MAP) was <30 mmHg. At HS 3 hours, shed blood was returned and splenectomy was performed. Intensive care was continued to 24 hours. RESULTS: At 24 hours, there were two survivors in the Norm group, four in the Hypo-Ice group and seven in the Hypo-Rm group (p < 0.05 versus the Norm group, Log Rank). Time required to achieve 34 degrees C was 17 +/- 9 minutes in the Hypo-Ice group and 15 +/- 4 minutes in the Hypo-Rm group (NS). Compared with the Hypo-Rm group, the Hypo-Ice group required less saline during early HS (321 +/- 122 versus 571 +/- 184 mL, p < 0.05). The Hypo-Ice group also had higher lactate levels than the Hypo-Rm group (p < 0.05). Hypothermia did not cause any increase in bleeding compared with normothermia. CONCLUSION: Mild hypothermia during HS, induced by infusion of room temperature saline and surface cooling, improves survival in a clinically relevant model of HS and trauma. However, the use of iced saline in this model had detrimental effects and did not cool the animal more quickly than room temperature fluids. These findings suggest that optimal methods for induction of hypothermia need to be addressed for each potential indication, e.g. cardiac arrest versus HS. 相似文献
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105.
A randomized, prospective study of 300 cholecystectomies was undertaken to evaluate the merits of drainage through a standard Penrose or Chaffin-Pratt sump tube matched against no drainage at all. There was no difference in mortality or length of hospital stay. There was, however, a significantly higher incidence of postoperative pyrexia due to atelectasis and wound infection in the drainage groups. Neither drain fulfilled its objective of providing outflow for a subhepatic collection, thus avoiding bile peritonitis. This study suggests that surgical drainage after every uncomplicated cholecystectomy is unnecessary and unwise. 相似文献
106.
A number of surgical clips and other metallic materials embedded within patients have ferromagnetic properties that present a potential hazard when in the strong fields associated with magnetic resonance imaging. Several types of magnetometers and metal detectors were investigated as possible pre-imaging screening devices. The sensitivities and costs of these devices are given. 相似文献
107.
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109.
Wei J Wu C Lankin D Gulrati A Valyi-Nagy T Cochran E Pike VW Kozikowski A Wang Y 《Current Alzheimer research》2005,2(2):109-114
To date, small-molecule amyloid-imaging agents for in vivo detection and quantitation of amyloid deposits in Alzheimer's disease (AD) have been developed and successfully applied to human subjects. Preliminary studies have indicated that these amyloid-imaging agents were accumulated in the AD brains in a pattern that is relatively consistent with AD pathology, at least in the regions of amyloid-rich grey matter. These studies have also proven the concept that amyloid dyes, normally too hydrophilic to enter the brain, can be chemically modified to enhance brain permeability, binding affinity, as well as improve binding specificity for amyloid deposits. Related studies have suggested that structurally different agents can be developed that bind to different sites on amyloid deposits. In fact, in vivo cross-referencing studies based upon different amyloid-imaging agents may permit better characterization of AD pathology. But more importantly, novel amyloid imaging agents are required that will allow direct correlation between the results of animal models and human subjects based upon identical imaging modalities. Thus far, amyloid stains such as Congo red and thioflavin T have been extensively studied. However, another widely used amyloid dye, thioflavin S, has not been previously explored. This is in part due to the fact that thioflavin S exists as a mixture, not a pure chemical entity, albeit that the major component has been characterized. We hypothesized that neutral analogs, based upon the major component, could be developed as novel amyloid imaging agents, that exhibit complementary binding properties and pharmacokinetic profiles compatible with potential human studies. 相似文献
110.
Overweight children and adolescents: a clinical report of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition 总被引:5,自引:0,他引:5
Baker S Barlow S Cochran W Fuchs G Klish W Krebs N Strauss R Tershakovec A Udall J 《Journal of pediatric gastroenterology and nutrition》2005,40(5):533-543
Childhood overweight and obesity are major health problems with immediate and long-term consequences of staggering magnitude. Despite this, there are few preventive and therapeutic strategies of proven effectiveness available to public health and clinical practitioners. Accruing such evidence is currently and appropriately a health policy priority, but there is an urgent need to intervene even before comprehensive solutions are fully established. The aim of this Clinical Report on Overweight Children and Adolescents is to present information on current understanding of pathogenesis and treatment of overweight and obesity. We report on the epidemiology, molecular biology and medical conditions associated with overweight; on dietary, exercise, behavioral, pharmacological and surgical treatments; and on the primary prevention of overweight in children and adolescents. 相似文献