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81.
Daily communications between the ICU trauma patients' families and the trauma team are often limited due to the unpredictable nature of subsequent patient admissions and operative procedures. In order to improve the lines of family-physician communication and educate residents regarding family communication, our level I trauma center instituted daily "Family Rounds" (FR). FR occur at the same time every day, in the patient's ICU room. The purpose of this study was to determine whether families valued the scheduled daily FR, to establish whether FR improved the family-physician relationship, and to delineate strengths and weaknesses of the present structure of our FR. We mailed surveys to family members of trauma patients hospitalized in the trauma ICU for > or = 3 days. A total of 55 (22%) families responded. Combining "excellent" and "good" responses, 86.5 per cent of families looked forward to having a specific time of day to meet with the trauma team, and 90 per cent liked having rounds in the ICU room with the patient. However, 36 per cent did not like having only scheduled time for FR. The majority, 75 per cent, believed that all concerns were addressed during FR, and 84.9 per cent rated their overall experience as either excellent or good. Scheduled FR appear to improve communication between trauma surgeons and patients' families, enhance the family-physician relationship, and strengthen our surgical residency teaching program.  相似文献   
82.
83.
The immune system is involved at all stages of the atherosclerotic disease process. Innate immunity, represented by macrophages and other cells, is directly activated by microbial components and possibly also by autologous lipids and proteins. It elicits inflammatory activity, which is a key component of the atherosclerotic lesion. Adaptive immunity is initiated by recognition of disease-related antigens, which include oxidatively modified lipoproteins, heat shock proteins and microbial macromolecules. In the artery wall, adaptive immune recognition mainly leads to Thl effector responses, which are characterized by secretion of proinflammatory cytokines and by activation of macrophages and vascular cells. Therefore, both the innate and adaptive arms of the immune system lead to inflammation in the developing atherosclerotic lesion. Interestingly, several effector pathways of cellular as well as humoral immunity tend to counteract proatherogenic, proinflammatory immunity. The notion that immunity plays an important role in the development of atherosclerosis has focused attention on a number of potential novel targets for intervention based on modulation of such immune responses.  相似文献   
84.
OBJECTIVE: Defects in insulin secretion and insulin action are the major abnormalities in the development of type 2 diabetes. In middle-aged subjects, elevated plasma proinsulin has been found to predict type 2 diabetes. Therefore, our aim was to study the longitudinal relationships between baseline determinations of insulin sensitivity index (S(i)) assessed by euglycemic insulin clamp, the early insulin response (EIR) at an oral glucose tolerance test (OGTT), fasting intact proinsulin, 32-33 split proinsulin and specific insulin, and the development of type 2 diabetes in a population-based cohort of 70-year-old nondiabetic men (n = 667) with 7-year follow-up. RESEARCH DESIGN AND METHODS: A euglycemic insulin clamp study and a 75-g OGTT were performed at baseline, and fasting peptide concentrations were measured using specific two-site immunometric assays. Results from logistic regression models are presented as odds ratios (ORs) with 95% CIs for a 1-SD increase in the predictor variable. RESULTS: In separate multivariate analyses adjusted for EIR (OR 0.72, 95% CI 0.59-0.89) and S(i) (0.68, 0.58-0.88), 32-33 split proinsulin (1.49, 1.18-1.88) or intact proinsulin (1.30, 1.04-1.63) were significantly associated with the development of type 2 diabetes, whereas specific insulin (1.24, 0.91-1.66) was not. The significant associations between 32-33 split or intact proinsulin and the development of type 2 diabetes were unaltered after adjustment for BMI and glucose tolerance. CONCLUSIONS: Insulin propeptides predicted type 2 diabetes over a 7-year period in elderly men, independent of the EIR and S(i).  相似文献   
85.
OBJECTIVE: We examined the effect of diazoxide, an ATP-sensitive K(+) channel opener and inhibitor of insulin secretion, on beta-cell function and remission in children at clinical onset of type 1 diabetes. RESEARCH DESIGN AND METHODS: A total of 56 subjects (21 girls and 35 boys, age 7-17 years) were randomized to 3 months of active treatment (diazoxide 5-7.5 mg/kg in divided doses) or placebo in addition to multiple daily insulin injections and were followed for 2 years. RESULTS: Diazoxide decreased circulating C-peptide concentrations by approximately 50%. After cessation of the treatment, basal and meal-stimulated C-peptide concentrations increased to a maximum at 6 months, followed by a decline. Meal-stimulated C-peptide concentration was significantly higher at 12 months (0.43 +/- 0.22 vs. 0.31 +/- 0.26 nmol/l, P = 0.018) and tended to fall less from clinical onset to 24 months in the diazoxide- vs. placebo-treated patients (-0.05 +/- 0.24 vs. -0.18 +/- 0.26 nmol/l, P = 0.064). At 24 months, the meal-stimulated C-peptide concentrations were 0.24 +/- 0.20 and 0.20 +/- 0.17 nmol/l, respectively. Side effects of diazoxide were prevalent. CONCLUSIONS: This study demonstrates that partial inhibition of insulin secretion for 3 months at onset of childhood type 1 diabetes suspends the period of remission and temporarily preserves residual insulin production. Further evaluation of the full potential of beta-cell rest will require compounds with less side effects as well as protocols optimized for sustained secretory arrest.  相似文献   
86.
Ketoprofen is a photolabile drug. The aim of the present study was to compare the bioavailability of ketoprofen in a photo-stabilised formulation with a gel without photoprotection using a new dermatopharmacokinetic tape-stripping model and an established ex vivo penetration method using human skin. Analyses of the stratum corneum showed that during the first 45 min about 12 microg/cm2 ketoprofen was absorbed into the skin from the formulations. The area under the ketoprofen content-time curve (AUC0-6 h) for the ratio photo-stabilised gel/transparent gel was 73% with a 90% confidence interval (CI) 65-83. The rate of penetration of ketoprofen through isolated skin was approximately 0.2 microg/cm2 h for both formulations. AUC0-36 h for the ratio was 84% with 90% CI 64-105. Thus, the two methods did not disagree in terms of relative efficacy of the two gels. However, the difference obtained in vivo was statistically significant, whereas no significant data arise from the ex vivo study. Comparing the amount of ketoprofen in the skin after 45 min with the amount penetrated through the excised skin during 36 h, suggests a change in the thermodynamic activity of ketoprofen during the exposure. A supersaturated formulation may well have been formed initially due to evaporation of ethanol.  相似文献   
87.
We present a method based on augmenting an exact relation between a frequency-dependent diffusion constant and the imaginary time velocity autocorrelation function, combined with the maximum entropy numerical analytic continuation approach to study transport properties in quantum liquids. The method is applied to the case of liquid para-hydrogen at two thermodynamic state points: a liquid near the triple point and a high-temperature liquid. Good agreement for the self-diffusion constant and for the real-time velocity autocorrelation function is obtained in comparison to experimental measurements and other theoretical predictions. Improvement of the methodology and future applications are discussed.  相似文献   
88.
HYPOTHESIS: Iliac vascular injuries incur high mortality. DESIGN: Retrospective 100-month study (January 1, 1992, through April 30, 2000). PATIENTS: One hundred forty-eight patients with 185 iliac vessel injuries. OUTCOME MEASURES: Survival and mortality, analyzed by univariate and logistic regression. RESULTS: Admission mean +/- SD systolic blood pressure was 81 +/- 42 mm Hg, mean Revised Trauma Score was 6.0 +/- 2.8, and mean Injury Severity Score was 20.0 +/- 9.5. The mechanism of injury was penetrating in 140 patients (95%) and blunt in 8 (5%). The mean estimated blood loss was 6246 +/- 6174 mL. Of the 185 injured vessels, 71 (99%) of 72 iliac arteries were repaired, 101 (89%) of 113 iliac veins were ligated, and 12 (11%) of 113 iliac veins were repaired. Overall survival was 51% (76/148). Mortality was 82% (49/72) in patients with exsanguination. Survival by vessel: iliac artery, 57% (20/35); iliac vein, 55% (42/76); and iliac artery and vein, 38% (14/37). Significant predictors of outcome were thoracotomy in the emergency department, associated aortic injury, inferior vena cava injuries, iliac artery and vein injury, intraoperative arrhythmia, and intraoperative coagulopathy. On logistic regression, independent risk factors for survival were absence of thoracotomy in the emergency department, surgical management, and arrhythmia. Mortality by grade on the Organ Injury Scale of the American Association for the Surgery of Trauma (AAST-OIS) was as follows: grade III, 35% (33/95); grade IV, 71% (24/34); and grade V, 79% (15/19). CONCLUSIONS: Mortality remains high. Associated vessel injuries and intraoperative complications predict mortality. AAST-OIS grade for abdominal vascular injuries correlates well with mortality.  相似文献   
89.
BACKGROUND: p53 protein plays an important role in the response to DNA damage, and radiotherapy can cause radiation dermatitis. p53 and p21 levels increase in vitro when DNA is damaged by UVA, UVB, or gamma-radiation. To determine whether this response occurs in human skin and predicts the level of radiation dermatitis, we investigated levels of p53 and p21 in skin exposed to different types of radiation as part of a randomized study of women with breast cancer to evaluate topical steroid or emollient cream treatments for radiation dermatitis of their irradiated breast. METHODS: After surgery but before receiving tangential 5-mV photo-beam radiotherapy (2 Gy and 54 Gy) to the affected breast parenchyma, multiple areas on the backs of 50 women were irradiated with UVA and other areas were irradiated with UVB. Skin biopsy samples were taken from areas of normal unirradiated skin and all irradiated areas, and p53 and p21 were detected immunohistochemically. All statistical tests are two-sided. RESULTS: In skin irradiated with UVA or UVB, medians of 4.4% (range = 0%-40.5%) or 45.5% (range = 5.3%-74.6%) p53-positive keratinocytes, respectively, were observed. Radiotherapy produced medians of 31.0% (range = 0%-79.3%) p53-immunoreactive cells after 2 Gy of radiation and 83.2% (range = 37.6%-95.2%) after 54 Gy of radiation. Despite large interindividual differences in p53 response, comparable increases in epidermal p53 response were independent of the type of radiation. A correlation between p53 and p21 was also evident (r(s) =.78). In breast skin, there was no association between the p53 response and the degree of erythema (a measure of radiation dermatitis) and no statistically significant difference between treatment arms and p21/p53 responses. CONCLUSIONS: Individual responses to radiation-induced DNA damage varied widely and may be independent of the type of radiation. The epidermal p53 response does not predict the degree of radiation dermatitis.  相似文献   
90.
Factor V deficiency has been identified in 8 of 8 patients 7--20 yr of age, with Philadelphia-positive (Ph1+) chronic myelogenous leukemia (CML). In these 8 patients, factor V deficiency was not due to hepatic dysfunction, factor V inhibitors, or disseminated intravascular coagulation. In 3 patients, factor V activity rose 10%--12% (0.10--0.12 U/ml) after the infusion of 28--31 ml/kg body weight of fresh frozen plasma (FFP). The rise persisted less than 14 hr. The mean measured postinfusion rise in factor V was 18% of the expected rise calculated from the volume of FFP infused in the patients' plasma volume. In 4 patients, a small transient rise in factor V activity occurred after splenectomy or plateletpheresis. Factor V deficiency was completely corrected after a marked reduction in bone marrow cellularity in 2 patients with Ph1+ CML treated with extensive chemotherapy, total body irradiation, and bone marrow transplantation. Factor V deficiency was retrospectively observed in 6 of 20 patients, ages 20--80 yr, with Ph1+ CML and 3 of 6 patients with other myeloproliferative disorders. The factor V deficiency appears to be associated with the large myeloid- megakaryocytic cell mass characteristic of CML and other myeloproliferative disorders.  相似文献   
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