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A significant number of casualties in previous conflicts died from peripheral vascular wounds. A well-designed tourniquet could possibly have prevented these deaths. The objective of this study was the identification of such a tourniquet. A survey of Special Operations corpsmen established important characteristics necessary in an ideal tourniquet. Because most available devices do not and patented ideas could not meet these criteria, a number of prototypes were developed. Seven potentially satisfactory tourniquets were evaluated by 15 Navy SEAL corpsmen. The success and timing of placement were recorded, and a follow-up questionnaire was completed. Of the several successful tourniquets, two were preferred. Tourniquets incorporating a windlass technique take longer to place and often fail when placed with only one hand. New, relatively simple tourniquet devices incorporating bladder and ratchet mechanisms can significantly improve tourniquet performance. 相似文献
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Inhibition of growth and induction of apoptosis in human cancer cell lines by tea polyphenols 总被引:47,自引:7,他引:47
In order to study the biological activities of tea preparations and
purified tea polyphenols, their growth inhibitory effects were investigated
using four human cancer cell lines. Growth inhibition was measured by
[3H]thymidine incorporation after 48 h of treatment. The green tea
catechins (-)-epigallocatechin-3-gallate (EGCG) and (-)- epigallocatechin
(EGC) displayed strong growth inhibitory effects against lung tumor cell
lines H661 and H1299, with estimated IC50 values of 22 microM, but were
less effective against lung cancer cell line H441 and colon cancer cell
line HT-29 with IC50 values 2- to 3- fold higher.
(-)-Epicatechin-3-gallate, had lower activities, and (-)- epicatechin was
even less effective. Preparations of green tea polyphenols and theaflavins
had higher activities than extracts of green tea and decaffeinated green
tea. The results suggest that the growth inhibitory activity of tea
extracts is caused by the activities of different tea polyphenols. Exposure
of H661 cells to 30 microM EGCG, EGC or theaflavins for 24 h led to the
induction of apoptosis as determined by an annexin V apoptosis assay,
showing apoptosis indices of 23, 26 and 8%, respectively; with 100 microM
of these compounds, the apoptosis indices were 82, 76 and 78%,
respectively. Incubation of H661 cells with EGCG also induced a
dose-dependent formation of H2O2. Addition of H2O2 to H661 cells caused
apoptosis in a manner similar to that caused by EGCG. The EGCG-induced
apoptosis in H661 cells was completely inhibited by exogenously added
catalase (50 units/ml). These results suggest that tea polyphenol-induced
production of H2O2 may mediate apoptosis and that this may contribute to
the growth inhibitory activities of tea polyphenols in vitro.
相似文献
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OBJECTIVE: To review the natriuretic hormone system and discuss its diagnostic, prognostic, and therapeutic potential in critically ill children. DATA SOURCE: A thorough literature search of MEDLINE was performed using search terms including heart defects, congenital; cardiopulmonary bypass, atrial natriuretic factor; natriuretic peptide, brain; carperitide; nesiritide. Preclinical and clinical investigations and review articles were identified that describe the current understanding of the natriuretic hormone system and its role in the regulation of vascular tone and fluid balance in healthy adults and children and in those with underlying cardiac, pulmonary, and renal disease. RESULTS: A predictable activation of the natriuretic hormone system occurs in children with congenital heart disease and congestive heart failure. Further study is needed to confirm preliminary reports that measurement of natriuretic hormone levels in critically ill children provides diagnostic and prognostic information, as has been demonstrated in adult cardiac populations. Natriuretic hormone infusions provide favorable hemodynamic changes and symptomatic relief when used in adults with decompensated congestive heart failure, and uncontrolled case series suggest that similar benefits may exist in children. The biological activity of the natriuretic hormone system may be decreased following pediatric cardiopulmonary bypass, and additional studies are needed to determine whether natriuretic hormone infusions provide clinical benefit in the postoperative period. Preliminary reports suggest that natriuretic hormone infusions cause physiologic improvements in adults with acute lung injury and asthma but not in those with acute renal failure. CONCLUSIONS: Although important perturbations of the natriuretic hormone system occur in critically ill infants and children, further investigation is needed before the measurement of natriuretic peptides and the use of natriuretic hormone infusions are incorporated into routine practice. 相似文献
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Experience with the holmium laser as an endoscopic lithotrite 总被引:1,自引:0,他引:1
Costello AJ Westcott MJ Peters JS 《The Australian and New Zealand journal of surgery》2000,70(5):348-350
INTRODUCTION: Holmium laser lithotripsy represents an additional option in the management of urinary tract calculi. We report the results of a cohort of patients with ureteric and bladder calculi treated with this modality. METHODS: Twenty-three patients underwent holmium laser lithotripsy to treat ureteric or bladder calculi. Power settings of 0.5 J to deliver 2.5-4.0 watts were used for the ureteric calculi, and up to 30 watts for the bladder calculi. RESULTS: The mean ureteric stone size was 7.3 mm (range 4-10 mm). One stone was upper ureteric, seven were mid-ureter and nine were lower-ureter. Eighteen of the 19 patients with ureteric calculi were free of stones 28 days postoperatively. The remaining patient was clear by 12 weeks. All patients with bladder calculi were completely cleared of stones. There were no intraoperative complications. DISCUSSION: Ureteric stone position can limit the use of extracorporeal shock wave lithotripsy due to imaging difficulties. Ureteric lithotripsy overcomes this problem. The holmium laser has proven to be safe and effective in clearing urinary stone burdens of a variety of sizes, sites and compositions in this cohort of patients. 相似文献
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Ansari MZ Costello AJ Ackland MJ Carson N McDonald IG 《The Australian and New Zealand journal of surgery》2000,70(3):204-208
BACKGROUND: The purpose of the present paper was (i) to identify trends in in-hospital mortality after transurethral resection of the prostate (TURP) in Victorian public hospitals; and (ii) to explore associations between in-hospital mortality after TURP and age, adverse events, type of admission (emergency/planned), location of the hospital (metropolitan/rural), teaching status of the hospital and length of stay. METHODS: Trends in in-hospital mortality after TURP and the associations between in-hospital mortality and the aforementioned variables were studied using International Classification of Diseases, 9th revision, Clinical Modification (ICD-9-CM) coded Victorian hospital morbidity data from public hospitals between 1987-88 and 1994-95. Crude and adjusted odds ratios (OR) and 95% confidence intervals (CI) were based on univariate and multivariate logistic regression, respectively. RESULTS: After adjustment for age, comorbidity, and other confounding variables, the trend in mortality reduction over time was highly significant (P for trend < 0.0001, 95% CI for trend: 0.84-0.95). Highly significant associations with mortality were observed for emergency admissions (OR = 1.99, P < 0.0001), presence of adverse events (OR = 2.69, P < 0.0001), length of hospital stay (P for trend < 0.0001, 95% for trend: 1.88-2.15) and age (P for trend < 0.0001; 95% CI for trend: 1.26-1.48). CONCLUSIONS: Routinely collected data from hospitals can provide tentative evidence of improved effectiveness of a surgical treatment, provided analysis takes careful account of potential sources of bias, especially those related to possible changes in case selection over time. These kinds of data should stimulate a joint effort between clinicians, quality assurance experts and epidemiologists to confirm this attribution, and to locate the causative factors. 相似文献
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