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51.
−1 for 1 to 4 min. Platelet deposition was determined using immunoenzymatic techniques to quantify P-selectine, a platelet membrane receptor, in thrombi. Fibrin deposition was determined by quantifying fibrin degradation products released after application of plasmin (D-dimers). Heparin was injected into the blood flow through a blender port system located between the venous puncture site and perfusion chamber. The results of the study showed that in a human ex vivo model, formation of arterial thrombus on two thrombogenic surfaces (tissue factor and collagen) is not inhibited by nonfractionated heparin.  相似文献   
52.
Intentional penetrating wounds, self inflicted or inflicted by others, are increasingly common. As a result, it can be difficult for the forensic examiner to determine whether the cause is self-inflicted or not. This type of trauma has been studied from a psychological perspective and from a surgical perspective but the literature concerning the forensic perspective is poorer. The objective of this study was to compare the epidemiology of abdominal stab wounds so as to distinguish specific features of each type. This could help the forensic scientist to determine the manner of infliction of the wound.We proposed a retrospective monocentric study that included all patients with an abdominal wound who were managed by the visceral surgery department at Angers University Hospital. Demographic criteria, patient history, circumstances and location of the wound were noted and compared. A comparison was drawn between group 1 (self inflicted wound) and group 2 (assault).This study showed that the only significant differences are represented by the patient's prior history and the circumstances surrounding the wound, i.e. the scene and time of day. In our study, neither the site, nor the injuries sustained reveal significant clues as to the origin of the wound. According to our findings, in order to determine the cause, the forensic examiner should thus carefully study the circumstances and any associated injuries.  相似文献   
53.
Objectives of this study were to compare rates of mental health disorders in Rwandan genocide perpetrators with those of genocide survivors and to investigate potential predictors of symptoms of posttraumatic stress disorder (PTSD) and depression for both groups. We expected high rates of mental disorders in both study groups and hypothesized that symptom severity would be predicted by female gender, older age, lower level of education, higher level of trauma exposure, lower level of agreement to reconciliation, and the participation in killing. Structured clinical interviews were carried out with 269 imprisoned perpetrators (66% men) and 114 survivors (64% women). Significantly more survivors than perpetrators met symptom criteria for PTSD (46% vs. 14%) and suffered from anxiety symptoms (59% vs. 36%). A substantial proportion of both groups suffered from clinically significant depression (46% vs. 41%). PTSD severity in perpetrators was associated with trauma exposure, high levels of agreement to reconciliation, and no participation in killing; the severity of depression was associated with trauma exposure and no participation in killing. In the survivor sample, the severity of PTSD and depression were both correlated with female gender, trauma exposure, and low levels of agreement to reconciliation. Results suggest that both groups exhibit considerable psychiatric morbidity.  相似文献   
54.
Acute nonvariceal upper gastrointestinal bleeding(UGIB) is a major medical emergency problem associated with significant morbidity and mortality.Endoscopy is considered the first method of choice to detect and treat UGIB.Endoscopic therapy usually achieves primary hemostasis,but 10%-30% of these patients have repeat bleeding.In patients in whom hemostasis is not achieved with endoscopic techniques,treatment with transcatheter angiographic embolization(TAE) or surgery is needed.Surgical intervention is usually an expeditious and gratifying endeavor,but it can be associated with high operative mortality rates.A large number of studies support the use of TAE as salvage therapy as an alternative to surgery.However,few studies have compared the results of TAE with that of emergency surgery in terms of efficiency,the frequency of repeat bleeding,and complications.Recently,Ang et al retrospectively compared the outcome of TAE and surgery as salvage therapy of UGIB after failed endoscopic treatment.There were no significant differences in 30 d mortality,complication rates and length of stay although higher rebleeding rates were observed after TAE compared with surgery.In this commentary,we discuss the advantages and drawbacks of these two therapeutic strategies for UGIB.We also attempt to define the exact role of TAE for acute nonvariceal UGIB.  相似文献   
55.
Background The presence of extrahepatic disease (EHD) is considered a contraindication to hepatectomy in patients with colorectal liver metastases. After resection, the prognosis is based more on the total number of resected metastases (located inside and outside the liver) than on the site of these metastases (only inside the liver or not). Methods A total of 308 patients with colorectal cancer underwent hepatectomy, and 84 (27%) also underwent resection of miscellaneous EHD. The study was a prospective data registration and retrospective analysis. When considering the total number of resected metastases, each liver metastasis and each EHD location was counted as one lesion. Univariate and multivariate analyses were performed. Results The median follow-up was 99 months. The overall 5-year survival rate was 32%. In the multivariate analysis, the total number of metastases (inside or outside the liver) had a greater prognostic value than the criterion “presence or absence of EHD.” Considering the total number of resected metastases (whatever their site), 5-year survival rates were 38% (SD: 4%) in the group with one to three metastases, 29% (SD: 5%) in patients with four to six metastases, and 18% (SD: 5%) in patients with more than six metastases (P = .002). A very simple prognostic score based on sex and the total number of metastases is proposed. Conclusions EHD, when resectable, is no longer a contraindication to hepatectomy. More importantly, the total number of the metastases, whatever their location, has a stronger prognostic effect than the site of these metastases.  相似文献   
56.
A clinical score to predict acute renal failure after cardiac surgery   总被引:7,自引:0,他引:7  
The risk of mortality associated with acute renal failure (ARF) after open-heart surgery continues to be distressingly high. Accurate prediction of ARF provides an opportunity to develop strategies for early diagnosis and treatment. The aim of this study was to develop a clinical score to predict postoperative ARF by incorporating the effect of all of its major risk factors. A total of 33,217 patients underwent open-heart surgery at the Cleveland Clinic Foundation (1993 to 2002). The primary outcome was ARF that required dialysis. The scoring model was developed in a randomly selected test set (n = 15,838) and was validated on the remaining patients. Its predictive accuracy was compared by area under the receiver operating characteristic curve. The score ranges between 0 and 17 points. The ARF frequency at each score level in the validation set fell within the 95% confidence intervals (CI) of the corresponding frequency in the test set. Four risk categories of increasing severity (scores 0 to 2, 3 to 5, 6 to 8, and 9 to 13) were formed arbitrarily. The frequency of ARF across these categories in the test set ranged between 0.5 and 22.1%. The score was also valid in predicting ARF across all risk categories. The area under the receiver operating characteristic curve for the score in the test set was 0.81 (95% CI 0.78 to 0.83) and was similar to that in the validation set (0.82; 95% CI 0.80 to 0.85; P = 0.39). In conclusion, a score is valid and accurate in predicting ARF after open-heart surgery; along with increasing its clinical utility, the score can help in planning future clinical trials of ARF.  相似文献   
57.
Visceral artery aneurysms (VAA) include splanchnic and renal artery aneurysms. They represent a rare clinical entity, although their detection is rising due to an increased use of cross-sectional imaging. Rupture is the most devastating complication, and is associated with a high morbidity and mortality. In addition, increased percutaneous endovascular interventions have raised the incidence of iatrogenic visceral artery pseudoaneurysms (VAPAs). For this reason, elective repair is preferable in the appropriately chosen patient. Controversy still exists regarding their treatment. Over the past decade, there has been steady increase in the utilization of minimally invasive, non-operative interventions, for vascular aneurysmal disease. All VAAs and VAPAs can technically be fixed by endovascular techniques but that does not mean they should. These catheter-based techniques constitute an excellent approach in the elective setting. However, in the emergent setting it may carry a higher morbidity and mortality. The decision for intervention has to take into account the size and the natural history of the lesion, the risk of rupture, which is high during pregnancy, and the relative risk of surgical or radiological intervention. For splanchnic artery aneurysms, we should recognize that we are not, in reality, well informed about their natural history. For most asymptomatic aneurysms, expectant treatment is acceptable. For large, symptomatic or aneurysms with a high risk of rupture, endovascular treatment has become the first-line therapy. Treatment of VAPAs is always mandatory because of the high risk of rupture. We present our point of view on interventional radiology in the splanchnic arteries, focusing on what has been achieved and the remaining challenges.  相似文献   
58.
BACKGROUND: This study evaluated the prevalence of the atherogenic metabolic triad and the hypothesis that waist circumference and fasting triglyceride concentrations could be used as screening tools for identification of the atherogenic metabolic triad in a population of heart transplant men. It also evaluated the relationship between the atherogenic metabolic triad and coronary artery disease (CAD). METHODS: In the study group of 83 consecutive male heart transplant patients having their routine annual coronarography, 23 patients (28%) were characterized by the atherogenic metabolic triad defined by the presence of elevated fasting insulin and apolipoprotein B concentrations and by small low-density lipoprotein (LDL) particles. RESULTS: Seventy-seven per cent of patients with waist circumference values >/= 90 cm and with elevated triglyceride levels (>/=2.0 mmol/liter) were characterized by this atherogenic metabolic triad. Patients with the atherogenic metabolic triad were at markedly increased risk of CAD (odds ratio of 25.3, 95% CI: 1.11-577.3, p < 0.04) compared to heart transplant patients without the atherogenic metabolic triad. CONCLUSIONS: About 30% of heart transplant patients showed the features of the atherogenic metabolic triad. Measurement and interpretation of waist circumference and fasting triglycerides could be used among heart transplant patients to early identify men characterized by the presence of elevated fasting insulin and apolipoprotein B concentrations and small LDL particles. The presence of the atherogenic metabolic triad identified patients at high risk of CAD even in the heart transplant population.  相似文献   
59.
BACKGROUND: Only 2 large (more than 100 patients) prospective trials comparing pancreatogastrostomy (PG) with pancreatojejunostomy (PJ) after pancreatoduodenectomy (PD) have been reported until now. One nonrandomized study showed that there were less pancreatic and digestive tract fistula with PG, whereas the other, a randomized trial from a single high-volume center, found no significant differences between the two techniques. METHODS: Single blind, controlled randomized, multicenter trial. The main endpoint was intra-abdominal complications (IACs). RESULTS: Of 149 randomized patients, 81 underwent PG and 68 PJ. No significant difference was found between the two groups concerning pre- or intraoperative patient characteristics. The rate of patients with one or more IACs was 34% in each group. Twenty-seven patients sustained a pancreatoenteric fistula (18%), 13 in PG (16%; 95% confidence interval [CI] 8-24%) and 14 in PJ (20%; 95% CI 10.5-29.5%). No statistically significant difference was found between the 2 groups concerning the mortality rate (11% overall), the rate of reoperations and/or postoperative interventional radiology drainages (23%), or the length of hospital stay (median 20.5 days). Univariate analysis found the following risk factors: (1) age > or =70 years old, (2) extrapancreatic disease, (3) normal consistency of pancreas, (4) diameter of main pancreatic duct <3 mm, (5) duration of operation >6 hours, and (6) a center effect. Significantly more IAC, pancreatoenteric fistula, and deaths occurred in one center (that included the most patients) (P = .05), but there were significantly more high-risk patients in this center (normal pancreas consistency, extrapancreatic pathology, small pancreatic duct, higher transfusion requirements, and duration of operation >6 hours) compared with the other centers. In multivariate analysis, the center effect disappeared. Independent risk factors included duration of operation >6 hours for IAC and for pancreatoenteric fistula (P = .01), extrapancreatic disease for pancreatoenteric fistulas (P < .04), and age > or =70 years for mortality (P < .02). CONCLUSIONS: The type of pancreatoenteric anastomosis (PJ or PG) after PD does not significantly influence the rate of patients with one or more IAC and/or pancreatic fistula or the severity of complications.  相似文献   
60.

Objective

To evaluate the clinical impact of diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) in staging of malignant lymphoma.

Methods

Twenty-three patients with proven malignant lymphomas were prospectively enrolled. DWIBS (b = 0, 1000 s/mm2) examinations and PET-CT were performed respectively on an Intera 1.5 T unit and a Gyroscan PET-CT scan (Philips Medical system, Best, the Netherland). The criteria for positive node involvement were a size over 10 mm or an apparent diffusion coefficient (ADC) value under 0.75 10−3 mm2/s for nodes under 10 mm. For extranodal analysis, a high or heterogeneous signal on DWIBS was considered as positive. In cases of discordance, the reference standard for each region or organ was established at 6 months after the diagnosis according to all available clinical, biological information, as well as histological evidence or follow-up to prove or disprove the presence of disease.

Results

DWIBS and PET-CT results were congruent in 333 node regions on the 345 areas analyzed, with excellent agreement (κ = 0.97, P < 0.0001). From 433 organs analyzed (one patient had splenectomy) extranodal disease was detected in 22 organs on DWIBS. The two imaging techniques agreed on 430 organs (κ = 0.99, P < 0.0001). Finally, Ann Arbor stages based on DWIBS and those of PET/CT were in agreement for 23 patients.

Conclusions

For malignant lymphoma in a pre-therapeutic context, agreement between diffusion-weighted whole-body imaging and PET/CT is high for Ann Arbor staging.  相似文献   
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