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Epithelial tumors of the ovary: comparison of MR and CT findings   总被引:12,自引:0,他引:12  
Forty patients with 50 ovarian epithelial tumors of the ovary were retrospectively studied. They underwent computed tomography and magnetic resonance (MR) imaging within 1 week of surgery. MR examinations were performed with a superconducting magnet (0.5 T) and predominantly T1- and T2-weighted MR imaging. T1-weighted MR images were obtained in eight patients after contrast material was administered. Signal intensity of tumors was compared with that of urine, muscle, and fat. Morphologic features that were evaluated included size, vegetations, septations, wall thickness, fluid or solid components, and vascularity. On the basis of signal intensity and morphologic characteristics, MR imaging helped in the correct diagnosis of benign serous cystadenoma in 10 of 13 tumors, benign mucinous cystadenoma in seven of 10 tumors, and tumors of low malignant potential and malignant tumors in 23 of 27 tumors. Accuracy for overall characterization of benign versus malignant tumors was 86% with MR imaging and 92% with computed tomography. There was no difference in sensitivity (P = 1) or specificity (P = .5).  相似文献   
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OBJECTIVE: To investigate the value of measuring total plasma protein and hemoglobin concentrations for the diagnosis of pulmonary edema secondary to scorpion envenomation. DESIGN AND SETTING: Retrospective study over a 4-year period in the medical intensive care unit of a university hospital. PATIENTS: 67 patients older than 3 years admitted in the intensive care unit for scorpion envenomation and stratified into two groups according to the presence of pulmonary edema assessed by a medical committee that took into account clinical, radiological, and blood gas data at admission and after treatment. Total plasma protein and hemoglobin concentrations were analyzed separately. RESULTS: At admission all patients with and without pulmonary edema exhibited polypnea and tachycardia. The mean plasma protein and hemoglobin concentrations were higher in patients with pulmonary edema (74+/-6 and 14.2+/-2.0 g/dl, respectively) than in those without pulmonary edema (64+/-6 and 12.3+/-1.4 g/dl). After 24 h plasma protein and hemoglobin concentrations decreased in the pulmonary edema group (-11 and -1.9 g/dl) despite a negative fluid balance (-500 ml). A plasma protein concentration of 70 g/l or more predicted the presence of pulmonary edema with a sensitivity of 80% a specificity of 96%, a positive predictive value of 97%, and negative predictive value of 77%. CONCLUSIONS: In scorpion-envenomed patients with cardiorespiratory manifestations high plasma protein and hemoglobin concentrations suggest the presence of pulmonary edema.  相似文献   
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Alternariol monomethyl ether (AME) is a major mycotoxin produced by fungi of the genus Alternaria and a common contaminant of food products such as fruits and cereals worldwide. AME can cause serious health problems for animals as well as for humans. In this study, human colon carcinoma cells (HCT116) were used to explore the mechanisms of cell death induced by AME. Exposure of HCT116 cells to AME resulted in significant cytotoxicity manifested by a loss in cell viability mainly mediated by activation of apoptotic process. AME activated the mitochondrial apoptotic pathway evidenced by the opening of the mitochondrial permeability transition pore (PTP), loss of the mitochondrial transmembrane potential (ΔΨm) downstream generation of O(2)(-), cytochrome c release and caspase 9 and 3 activation. Experiments conducted on isolated organelles indicated that AME does not directly target mitochondria to induce PTP-dependent permeabilization of mitochondrial membranes. Moreover, no difference was observed in Bax-KO cells in comparison to parental cells, suggesting that the pro-apoptotic protein Bax is not involved in AME-induced mitochondrial apoptosis. Our findings demonstrate for the first time that AME induces cell death in human colon carcinoma cells by activating the mitochondrial pathway of apoptosis.  相似文献   
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Short-term effects of pyrethroids on human health are better and well identified, whereas long-term risk’s estimation remains difficult, especially those affecting the reproductive function. The present study, carried out in male rats, is a contribution to explore some effects underlying permethrin (PRMT) toxicity. The aim of the present work was to investigate the effect of different subcutaneous treatments with PRMT low doses on testes and epididymides histopathology, testosterone and oxidative stress in pubescent male rats. Groups of six animals were treated with a dermal daily dose of 0.013, 0.13, or 1.3 mg/kg b.w/day of PRMT in 70% ethanol for 30, 45, and 60 days, respectively.Macroscopic studies showed an influence of PRMT on the testes, the epididymides and body weight. The pyrethroid induces a testis disturbance traduced by a deregulation of spermatogenesis and an epididymis dysfunction by the appearance of strong deformations into the microstructure of the epididymides. A hormonal disruption was evidenced by the measurement of the plasma testosterone concentrations. The findings of the present investigation mentioned a significant increase (p≤0.05) in lipoperoxidation, after 45 or 60 days, when we measured the plasma malondialdehyde (MDA) concentrations.In conclusion the study shows that subcutaneous PRMT treatment causes an arrest of spermatogenesis, and a significant disharmony in testosterone concentration and MDA levels. These effects are related to dose, length of treatment and to the lipid peroxidation, which may be one of the molecular mechanisms involved in PRMT-induced gonads and epididymides toxicity.  相似文献   
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Objective

To compare the efficiency of a 7-day antibiotics regimen with a 10-day regimen for ventilator-associated pneumonia (VAP).

Study design

Prospective randomized study.

Patients and methods

Adults patients ventilated for more than 48 hours in the intensive care unit (ICU) with a clinical diagnosis of VAP documented by positive quantitative cultures of tracheal aspiration were included in this study. All included patients were randomized in two groups. Ten-day group: 10 days antibiotic therapy, and 7-day group: 7 days antibiotic therapy. Primary judgment criteria were 14- and 28-day mortality, the number of days without antibiotics. Secondary judgments criteria were rate of recurrent pulmonary infection, the evolution of the clinical pulmonary infection scores (CPIS), the length of ICU stay and the length of mechanical ventilation.

Results

Thirty patients were included in this study (16 in the 10-day group and 14 in the 7-day group). The demographic and clinical characteristics of the groups assigned to receive antibiotic therapy for 7 or 10 days were generally similar. The 14-day and 28-day mortality rate following VAP onset were 31.2 and 37.5% in the 10-day group and 7.1 and 35.7% in the 7-day group. The difference was not significant. The number of day without antibiotics and without mechanical ventilation turned out: 1.75 and 2.06 days versus 4.14 and 3.43 days in the 10-day group and 7-day group respectively, the recurrent rate of pulmonary infection (12.5% versus 14.3%, p = 0.6), the length of stay in the ICU (27.7 days versus 26.0 days, p = 0.8) and the evolution of the CPIS were no different in the two groups.

Conclusion

In patients with microbiologically confirmed VAP who received appropriate empirical antibiotic therapy, a 7-day antibiotic regimen was as efficient clinically and microbiologically as a 10-day antibiotic regimen with a reduction of antibiotic use.  相似文献   
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Background: The management of recurrent choledocholithiasis today remains as challenging as in the pre‐endoscopic era. Between 2 and 7% of affected patients have historically required surgical intervention for the treatment of recurrent or retained choledocholithiasis and of these, as many as 24% develop biliary complications. To avoid surgery, repeated endoscopic management of the problem has been suggested. In this study, we evaluate our policy of repeated endoscopic management of recurrent primary bile duct stones. Methods: This study examined a cohort of nine patients identified from a prospective database with recurrent choledocholithiasis. Demographic, clinical and investigative details were recorded and data were analysed. Complications were determined from a review of the patient’s file. Results: There were nine patients and 66 procedures were carried out. Mean age at time of first endoscopy was 70.1 years (36–91 years). Three patients were of male sex (33.3%). The mean number of endoscopies carried out per patient was 7.3 (3‐13). Failure to completely clear the duct occurred in 36.4% of all endoscopies. There were no periprocedural complications. Conclusion: Repeated endoscopic stone extraction by endoscopic retrograde cholangiopancreatography when required is a safe policy. However, this technique will only provide temporary relief from primary duct stones and repeated endoscopic treatment, again safe, will be required.  相似文献   
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