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991.
Acute reactions to trauma are examined in 267 individuals severely injured via community violence. Respondents were interviewed about pretrauma, peritraumatic, and acute posttraumatic factors. A series of bivariate and multivariate analyses were conducted. We found few factors related to peritraumatic dissociation (PD): only injury severity and neuroticism emerged as multivariate predictors and the effects were small. PD was strongly related to acute PTSD symptoms, and partially mediated the relationship between other factors and acute PTSD and general distress symptoms. Different patterns of predictors emerged for acute PTSD symptoms vis-à-vis general distress symptoms. Future research on predictors of PD is indicated to develop prevention and early intervention programs.  相似文献   
992.
Preoperative detection of pancreatic insulinomas on multiphasic helical CT   总被引:11,自引:0,他引:11  
OBJECTIVE: The objective was to analyze enhancement characteristics of insulinomas and to determine the ability of multiphase CT to localize these tumors. MATERIALS AND METHODS: Prospective interpretations of multiphase helical CT scans were reviewed in 30 patients who had insulinomas resected over a 5-year period. CT scans were retrospectively reviewed to determine enhancement characteristics, tumor conspicuity in each phase of enhancement, and potential causes for false-negative findings. RESULTS: Sixty-three percent (19/30) of tumors were identified on CT prospectively. An additional six tumors were visualized in retrospect, allowing characterization of 25 (83%) of 30 tumors. Most tumors were hyperdense on at least one phase (n = 19), three tumors were hypoattenuating, and three were isodense and pedunculated. Insulinomas were most conspicuous on the early phase in 15 patients and in the portal venous phase in three. All tumors that underwent pancreatic phase imaging were seen (13/13), whereas three of 18 arterial and six of 25 portal venous phase findings were inconclusive for tumor. In the six examinations with false-negative findings in which the tumor could be seen in retrospect, two tumors were isodense and pedunculated, three were in close proximity to vessels, and one had a cystic appearance. CONCLUSION: Multiphasic CT has a moderate sensitivity in the detection of insulinomas. Most tumors are more conspicuous on the earlier phases of enhancement. The pancreatic phase may be more useful than the arterial phase. Potential sources of false-negative results include tumors adjacent to vessels, pedunculated morphology, or nonhyperattenuating lesions.  相似文献   
993.
OBJECTIVE: To measure local (peritoneal fluid) and systemic (plasma) cytokine profiles in patients with infection-inflammation of the vermiform appendix, a relatively mild, localized inflammatory process. SUMMARY BACKGROUND DATA: The systemic host response to invading microorganisms, often termed the systemic inflammatory response syndrome (SIRS), includes changes in heart rate, respiratory rate, body temperature, and circulating white blood cell numbers. Although these changes can be induced experimentally by administering proinflammatory cytokines, the mediators that appear in the bloodstream during early, localized infection in humans have not been defined. METHODS: The authors studied 56 patients with pathologically proven appendicitis. Blood was obtained before the induction of anesthesia, when 82% of the patients met the criteria for SIRS. Peritoneal fluid (PF) was obtained by intraoperative lavage. Cytokines were measured by immunoassay. To assess the net impact of the mediators within plasma, the authors studied the ability of patient plasma to augment or suppress bacterial lipopolysaccharide (LPS) stimulation of monocytes in vitro. RESULTS: Of the proinflammatory cytokines, tumor necrosis factor-alpha was present in PF but not in plasma, interleukin (IL)-1beta and interferon-gamma were found in low concentrations in both PF and plasma, and IL-12 (p70) was detectable in plasma but not PF. In contrast, IL-6 and IL-1 receptor antagonist (IL-1ra) were the most abundant cytokines in the PF and plasma, and the concentrations of IL-4 and IL-10 were also elevated in both compartments. Patients with more severe appendicitis had higher plasma levels of IL-6 and IL-10 and lower plasma levels of IL-12 and interferon-gamma than did those with uncomplicated disease. Patient plasma inhibited LPS-induced stimulation of a monocyte cell line, and this inhibition was accentuated by complicated disease. CONCLUSIONS: As judged from the pattern of soluble cytokines in plasma and the effect of the plasma on monocyte activation by LPS, mild, localized infection can induce a systemic response that is predominantly anti-inflammatory.  相似文献   
994.
995.
Zygomycosis is a rare fungal infection that may present as a necrotizing soft tissue infection in the neonate. This report illustrates the typical presentation of a premature, infant with a rapidly progressive soft tissue necrotizing infection of his upper extremity at an intravenous site. Early diagnosis with tissue biopsy confirmed the diagnosis of Zygomycosis. Successful treatment required systemic amphotercin B and aggressive debridement requiring through-the-elbow amputation for survival.  相似文献   
996.
The effects of infusions of adrenaline, noradrenaline and dopamine on cerebral autoregulation under steady-state isoflurane anaesthesia were compared with the awake state. Six studies each were conducted in two cohorts of adult ewes: awake sheep and those anaesthetized with 2% isoflurane anaesthesia. In random order, each animal received ramped infusions of adrenaline, noradrenaline (0-40 micrograms/min) and dopamine (0-40 micrograms/kg/min). Cerebral blood flow was measured continuously from changes in Doppler velocities in the sagittal sinus. Autoregulation was determined by linear regression analysis between cerebral blood flow and mean arterial pressure. Isoflurane did not significantly alter cerebral blood flow relative to pre-anaesthesia values (P > 0.05). All three catecholamines significantly and equivalently increased MAP from baseline in a dose dependent manner in both the awake and isoflurane cohorts. Although adrenaline significantly increased cerebral blood flow from baseline in the awake cohort (P < 0.01), none of the catecholamines significantly increased cerebral blood flow during isoflurane anaesthesia. No significant differences were demonstrated between the slopes and intercepts of regression lines for adrenaline, noradrenaline and dopamine within either cohort (ANCOVA). Inter-cohort comparisons between the two autoregulation curves demonstrated no significant difference between the slopes of the autoregulation curves for the awake (pooled slope = 0.39) and isoflurane cohorts (pooled slope = 0.28) (P > 0.05). Over a specific dose range, systemic hypertension induced by adrenaline, noradrenaline and dopamine did not significantly increase cerebral blood flow under 2% isoflurane anaesthesia. The concomitant administration of isoflurane and the catecholamines was not associated with altered autoregulatory function compared to the awake state.  相似文献   
997.
BACKGROUND: We aimed to provide unbiased estimates of cost-effectiveness by systematically reviewing published cost and cost-effectiveness data derived from studies with rigorous designs that compared laparoscopic with open groin hernia repair. METHODS: Studies reporting costs and outcomes were identified as part of a systematic review of randomized controlled trials comparing laparoscopic with open repair. The quality of the included studies was assessed against a standard checklist. Cost per recurrence avoided and cost per additional day at usual activities were estimated. RESULTS: Fourteen studies were identified. Laparoscopic repair was less efficient than open mesh repair in terms of avoiding recurrences, avoided but it had a modest cost per additional day back at usual activities. Laparoscopic repair is more likely to be efficient when compared with open nonmesh repair. CONCLUSION: The type of open repair with which laparoscopic repair is compared influences its cost-effectiveness. The earlier return to usual activities provided by laparoscopic repair may make it worthwhile in some circumstances.  相似文献   
998.
BACKGROUND: Patients frequently arrive in emergency departments (EDs) after being resuscitated from opioid overdose. Autopsy studies suggest that multidrug intoxication is a major risk factor for adverse outcomes after acute heroin overdose in patients. If this is true, there may be high-risk drug combinations that identify patients who require more intensive monitoring and prolonged observation. Our objective was to determine the impact of co-intoxication with alcohol, cocaine, or CNS depressant drugs on short-term adverse event rates in patients resuscitated from acute opioid overdose. METHODS: Data were extracted from the database of a prospective opioid overdose cohort study conducted between May 1997 and 1999. Patients were prospectively enrolled if they received naloxone for presumed opioid overdose. Investigators gathered clinical, demographic, and other predictor variables, including co-intoxicants used. Patients were followed to identify prespecified adverse outcome events occurring within 24 h, and multiple logistic regression was used to determine the association of concomitant drug use on short-term adverse event rates. RESULTS: Of 1155 patients studied, 58 (5%) had pure opioid overdose and 922 (80%) reported co-intoxicants, including alcohol, cocaine, and CNS depressants. Overall, out of 1056 patients with known outcome status there were 123 major adverse events (11.6%) and 194 minor adverse events (18.4%). After adjustment for age, gender, HIV status, cardiovascular disease, pulmonary disease and diabetes, we found that coadministration of alcohol, cocaine, or CNS depressants, alone or in combination, was not associated with increased risk of death or adverse events during the 24 h follow-up period. CONCLUSION: In patients resuscitated from acute opioid overdose, short-term outcomes are similar for patients with pure opioid overdose and multidrug intoxications. A history of cointoxication cannot be used to identify high-risk patients who require more intensive ED monitoring or prolonged observation.  相似文献   
999.
1000.
The use of primary hepatocyte cultures as in vitro models for studying xenobiotic metabolism and toxicity is limited by the loss of liver-specific differentiated functions with time in culture and the inability of the cells to proliferate. The aim of this study was to investigate the effect of incorporating 20% chondroitin-6-sulphate (Ch6SO4), a glycosaminoglycan (GAG), into collagen gels (0.3% w/v) and crosslinking the gels with either 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDAC) or 1,6-diaminohexane (DAH) on the expression of glutathione-S-transferases (GSTs) and the activity of cytochrome P450 in hepatocytes cultured for 48 hours and 7 days. Hepatocytes were isolated from male Sprague-Dawley rats by collagenase perfusion. Cell homogenates were immunoblotted against class alpha and pi GST subunits. To measure cytochrome P450 activity, testosterone hydroxylation was assessed. Viability of the cultured cells was assessed by confocal laser scanning microscopy using the vital stain carboxyfluorescein diacetate (CFDA). Cells cultured on gels crosslinked with EDAC were dead by 48 hours as judged by lack of CFDA-derived fluorescence and absence of GST bands on the immunoblots. The viability and morphology of the cells were unaffected by any of the other components of the substrata tested. Expression of GSTs indicated that the hepatocyte phenotype was stable for at least 48 hours. The addition of GAG did not improve the phenotype at either 48 hours or 7 days in culture, but the combination of GAG and DAH crosslinking improved GST expression in the 7-day cultures. However, the hepatocyte cytochrome P450 activity did not show any improvement on any of the gels. The combination of GAG and DAH crosslinking provided the most stable substratum environment in terms of GST expression in hepatocytes.  相似文献   
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