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11.
Boerhaave’s syndrome is a life-threatening disease with a high mortality. With regard to the heterogeneity of treatment strategies, no comparative studies exist and recommendations remain controversial. Seventeen cases of Boerhaave’s syndrome operated on between 1989 and 2000 at our hospital were reviewed retrospectively to compare the time period between perforation and diagnosis, and the morbidity and mortality among the different treatment options. In addition, we conducted a meta-analysis of the literature including all series containing five or more patients and compared the findings with our own data. Our patients with a perforation history of less than 12 hours showed significantly fewer signs of sepsis compared to patients with a history of more than 12 hours. In a comparison of patients with primary repair vs. patients treated with esophageal resection or an exclusion operation, no differences were found. In the literature, patients with a long period of perforation (more than 24 hours) were treated more often with an esophageal resection than patients with primary repair. In cases of Boerhaave’s syndrome, primary suturing of the esophageal perforation should be reserved only for those patients presenting within 12 hours after perforation. In all other cases, depending on the extent of the tissue damage, a two-stage esophageal resection with cervical esophagostomy and gastrostomy is recommended as the safest treatment.  相似文献   
12.
Parallel image reconstruction using B-spline approximation (PROBER).   总被引:1,自引:0,他引:1  
A new reconstruction method for parallel MRI called PROBER is proposed. The method PROBER works in an image domain similar to methods based on Sensitivity Encoding (SENSE). However, unlike SENSE, which first estimates the spatial sensitivity maps, PROBER approximates the reconstruction coefficients directly by B-splines. Also, B-spline coefficients are estimated at once in order to minimize the reconstruction error instead of estimating the reconstruction in each pixel independently (as in SENSE). This makes the method robust to noise in reference images. No presmoothing of reference images is necessary. The number of estimated parameters is reduced, which speeds up the estimation process. PROBER was tested on simulated, phantom, and in vivo data. The results are compared with commercial implementations of the algorithms SENSE and GRAPPA (Generalized Autocalibrating Partially Parallel Acquisitions) in terms of elapsed time and reconstruction quality. The experiments showed that PROBER is faster than GRAPPA and SENSE for images wider than 150x150 pixels for comparable reconstruction quality. With more basis functions, PROBER outperforms both SENSE and GRAPPA in reconstruction quality at the cost of slightly increased computational time.  相似文献   
13.
OBJECTIVE: Although somatoform disorders are assumed to be chronic clinical conditions, epidemiological knowledge on their natural course based on representative samples is not available. METHOD: Data come from a prospective epidemiologic study of adolescents and young adults in Munich, Germany. Respondents' diagnoses (N = 2548) at baseline and follow-up on average 42 months later are considered. The follow-up incidence, stability as well as selected baseline risk factors (sociodemographics, psychopathology, trauma exposure) for the incidence and stability of somatoform disorders and syndromes are prospectively examined. Diagnostic information was assessed by using the standardized Munich-Composite International Diagnostic Interview (M-CIDI). RESULTS: Over the follow-up period, incidence rate for any of the covered somatoform diagnoses was 25.7%. Stability for the overall group of any somatoform disorder/syndrome was 48%. Female gender, lower social class, the experience of any substance use, anxiety and affective disorder as well as the experience of traumatic sexual and physical threat events predicted new onsets of somatoform conditions, while stability was predicted by being female, prior existing substance use, affective and eating disorders as well as the experience of a serious accident. CONCLUSIONS: At least for a substantial proportion of individuals, the overall picture of somatization seems to be relatively stable, but with fluctuation in the symptom picture over time. Being female, the experience of substance use as well as anxiety disorder seem to constitute risk factors for the onset of new somatoform conditions as well as for a stable course over time.  相似文献   
14.
Positron emission tomography (PET) using [(11)C]PK 11195, a ligand for peripheral benzodiazepine receptor binding sites, offers the opportunity to image activated microglia in vivo. This tool may therefore be used to display the occurrence of microglial activation in the course of neurodegeneration. A patient with the clinical diagnosis of corticobasal degeneration (CBD) and left-sided symptoms was studied using fluorodeoxyglucose (FDG) and [(11)C]PK 11195 PET. We found a marked right hemispheric hypometabolism and asymmetric microglial activation in corresponding areas of the basal ganglia and right temporal and parietal cortex. [(11)C]PK 11195 PET suggests involvement of microglial activation in the pathogenesis of CBD.  相似文献   
15.
Three cases with suspected pulmonary artery embolism are presented, in which transesophageal echocardiography showed a mass in the right pulmonary artery consistent with thrombus. The relevant diagnostic contributions of transesophageal echocardiography are discussed.  相似文献   
16.
PURPOSE: The low incidence of mortality and major morbidity in anesthesia makes it difficult to study the pattern of potential accidents and to develop preventive strategies. Anesthetic 'near-misses', however, occur more frequently. Using data from a simple routine-based system of problem reporting, we have analyzed the pattern and causes of serious non-fatal problems, in order to improve preventive strategies. METHODS: We prospectively recorded anesthesia-related information from all anesthetics for five years. The data included intraoperative problems, which were graded into four levels, according to severity. We analyzed only the serious nonfatal problems, which were sorted according to clinical presentation, and also according to which factor was most important in the development of the problem. We assessed any untoward consequences for the patient, and whether the problems could have been prevented. RESULTS: Serious problems were recorded in 315 cases out of 83,844 (0.4%). Anesthesia was considered the major contributing factor in 111 cases. Difficult intubation, difficult emergence from general anesthesia, allergic reactions, arrhythmia and hypotension were the dominating problems. Twenty-six anesthesia related problems resulted in changes in level of postoperative care, and one patient later died in the intensive care unit after anaphylactic shock. Eighty-two problems could have been prevented by simple strategies. CONCLUSION: Analysis of serious nonfatal problems during anesthesia may contribute to improved preventive strategies. Data from a routine-based system are suitable for this type of analysis. Intubation, emergence, arrhythmia, hypotension and anaphylaxis cause most serious problems, and should be the object of preventive strategies.  相似文献   
17.
The effects of the serotonin-releasing compound p-chloroamphetamine (PCA, 2.5 mg/kg) on avoidance acquisition, retention and memory retrieval were examined in male Sprague-Dawley rats using a one-way active avoidance and a one-trial passive avoidance task. The drug was injected IP prior to training, following acquisition and prior to the retention test 24 hr after training using a state-dependent design. In the normal context situation pretraining administration of PCA markedly impaired active avoidance acquisition, but PCA-treated rats did not differ from controls in their retention performance when tested 24 hr after training. In the dark/light box test pretraining administration of PCA caused a dose-dependent impairment of both active and passive avoidance retention which could not be explained in terms of changes in locomotor activity or behavioural disinhibition at the time of testing or state-dependent retention. Post-training administration of PCA failed to affect avoidance retention in both tasks. The drug was found to impair memory retrieval in a dose- and time-dependent fashion in the one-way active but not in the passive avoidance test. Pretraining administration of PCA produced a progressive loss of passive and active avoidance performance at increasingly longer retention intervals. The present results suggest that serotonin has dual effects on processes underlying learning and memory involving effects on both associative and non-associative learning processes in the rat. The time-dependent loss of memory retention following 5-HT release indicates that serotonin has a role in the way information is processed in the brain.  相似文献   
18.
19.
Objectives Even in the days of modern microsurgery, the removal of a brain stem lesion remains a surgical challenge. Especially when operating on children, the prognosis is directly related to the radicality of the resection; however, a radical resection is often associated with surgical morbidity. Intraoperative neuromonitoring could help to minimise the surgical morbidity, but few studies have been performed to clarify the value of this monitoring. We investigated a prospective series of 21 patients with lesions involving the brain stem for the prognostic value and benefits of neuromonitoring.Methods We performed intraoperative neuromonitoring of cranial nerve function by electromyography (EMG) and motor evoked potential (MEP). The results were correlated with postoperative neurological deficits.Conclusions There is a good correlation between intraoperative neurophysiological events and postoperative neurological deficits in patients with lesions of the brain stem. In general, transient, prolonged, spontaneous activity in EMG is associated with a transient paresis of the respective muscle, whereas a permanent spontaneous activity is associated with a permanent deficit. Intraoperative neuromonitoring reliably predicts postoperative neurological function in patients with tumours of the lower brain stem and fourth ventricle. This neuromonitoring guides the neurosurgeon in the operation and may decrease surgical morbidity. We recommend using monitoring of MEP and EMG of the lower cranial nerves in surgery on all patients with lesions involving the lower brain stem and fourth ventricle.  相似文献   
20.
Familial amyloidotic polyneuropathy (FAP) with a mutation in position 30 of transthyretin (TTR) (previously called prealbumin) is an autosomal dominant inherited disorder characterized by varying degrees of peripheral neuropathy, nephropathy, gastrointestinal problems, and vitreous amyloid. We have earlier diagnosed homozygosity for the TTR-Met30-gene using Southern analysis in four Swedish individuals. We have found it possible to detect homozygosity for the Met-30 mutation by amplifying discrete regions of the TTR-gene using polymerase chain reaction (PCR), and the amplification products restricted with NsiI analysed by gel electrophoresis. Clinical data on seven homozygous individuals, including three new cases, are presented.  相似文献   
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