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991.
Temporal bone dissection plays an important role in the training of surgeons; however, they are difficult to obtain.AimTo develop a synthetic replica of the temporal bone for dissection training.Study DesignExperimental.Materials and MethodsAn acrylic synthetic resin replica was obtained from a human temporal bone. For the evaluation of the method, we selected five ear surgeons to dissect the model in a laboratory of experimental surgery. A questionnaire was filled, assessing external appearance, the simulation of procedures (placement of ventilation tube, mastoidectomy, decompression of the facial nerve and translabyrinthine access to the internal auditory canal) and their final conclusion.ResultsThe evaluation indicated satisfaction in using the model (80%), being more evident concerning the dissection of the mastoid segment of the facial nerve and translabyrinthine access to the internal auditory canal. The placement of a ventilation tube was reasonable for 60% and satisfactory for 40% of them. Mastoidectomy was satisfactory for 60% and fully satisfactory for 40%.ConclusionDissection in this simulator does not replace otologic training in cadaveric temporal bones. However, given the increasing difficulty in obtaining the latter, the development of new teaching tools should be encouraged to continuously improve surgeons.  相似文献   
992.
993.
We carried out a cohort study in the Italian province of Trieste (2001 population, 242,000) to ascertain whether the risk of a subsequent primary cancer among 265 individuals diagnosed with a first malignancy at ages up to 25 years between 1971 and 1993 differed from that in the general population and to evaluate the effect of cancer family history, quantified by the family risk index (FRI), on the occurrence of second primaries. During the follow-up (median duration = 10 years; 25th-75th percentile = 2-16), 15 cohort members developed a second cancer vs. 1.60 expected for a standardized incidence ratio (SIR) of 9.4 (p < 0.0001). The overall SIR fell to 4.7 (p = 0.004) after excluding the 8 patients with well-known cancer-predisposing conditions (SIR = 300.0; p < 0.0001) and the 50 with a positive family history (FRI >/= 1.0) of malignant tumors (SIR = 20.0; p < 0.0001). Among 114 patients treated with radiotherapy and chemotherapy for their first neoplasms and not affected by predisposing disorders, 23 with a positive family history of cancer showed a 6.4-fold excess risk of second primaries (p = 0.008) compared with 91 with a negative history (FRI < 1.0). It is imperative that clinicians carefully and regularly evaluate cancer family history of young patients with malignancies. This would enable them to identify possible individual and familial features in patients at higher risk of multiple primaries and to adopt more suitable preventive and therapeutic measures.  相似文献   
994.
995.
996.
Activity of cathelicidin peptides against Chlamydia spp   总被引:2,自引:0,他引:2       下载免费PDF全文
The in vitro activity of six cathelicidin peptides against 25 strains of Chlamydia was investigated. SMAP-29 proved to be the most active peptide, reducing the inclusion numbers of all 10 strains of Chlamydia trachomatis tested by > or =50% at 10 microg/ml. This peptide was also active against C. pneumoniae and C. felis.  相似文献   
997.
Introduction: Medical education provides students with abundant learning opportunities, each of which is embodied with messages concerning what is expected from students. This paper analyses students? exposure to instances of unprofessional behavior, investigating whether they judge such behavior to be unprofessional and whether they also participate in unprofessional behavior.

Methods: The survey developed in the Pritzker School of Medicine at the University of Chicago was the basis of this questionnaire that was answered by 276 students from two medical schools in Brazil and Portugal.

Results: Unprofessional behavior was observed frequently by students in both universities, and the mean participation rates were similar (26% and 27%). Forty-five percent of students? participation in unprofessional behavior was explained by academic year, prior observation, and judgment.

Discussion: The results indicate that once students have observed, participated in or misjudged unprofessional behavior, they tend to participate in and misjudge such behavior. The frequency with which students judged behaviors they had observed or participated in as ?borderline? or unprofessional could mean that they are experiencing moral distress.

Conclusion: Proper discussion of unprofessional behavior should foster a broad debate to encourage empowered students, faculties, and physicians to co-create a more professional environment for patient care.  相似文献   
998.

Introduction

Lymphatic drainage patterns from the breast have been described in the past. Drainage may change after treatment of a breast or axilla, and this may have implications for lymphatic mapping. The aim of this study was to determine the lymphatic drainage patterns in breast cancer patients with a previously treated ipsilateral breast.

Methods

Between January 1999 and November 2008, 115 sentinel node procedures were performed in breast cancer patients who had undergone treatment of the ipsilateral breast in the past. Lymphatic drainage patterns were analyzed based on preoperative lymphoscintigraphy and sentinel lymph node biopsy. Patients were divided into subgroups according to their previous treatment.

Results

Sentinel nodes were found in 84% of the patients: in 81 patients (70%) in the axilla, 43 patients (37%) had drainage to more than one site, and in 18 patients (16%) no drainage was detected. The percentage of drainage outside the axilla was higher than in a series of untreated breast cancer patients from our institution (51% versus 33%, P = 0.01). The 16% nonidentification rate was also higher than the 3.1% in patients without previous treatment (P = 0.003). Four patients (3.5%) had lymphatic drainage to the contralateral axilla. Twelve patients (10%) had involved sentinel nodes; these were harvested from the contralateral axilla in two of them. No lymph node recurrences were observed during a median follow-up time of 39 months.

Conclusion

Lymphatic mapping yields a lymph node in 84% of breast cancer patients who have undergone previous treatment of the breast. Nonidentification and extra-axillary nodes are more frequently encountered than in patients without treatment of the breast in the past. The finding of involved nodes suggests that sentinel node biopsy improves staging. Long-term follow-up will determine the sensitivity of the procedure in this specific situation.  相似文献   
999.
1000.
The aim of this study was to describe the clinical course of Crohn's disease (CD) in a well-defined, homogeneous groups of patients. A total of 480 patients with CD were followed up from diagnosis up to 20 years. Definitions of patient subgroups were made according to the Vienna Classification. Markov chain analysis was used to estimate the probabilities of remissions and relapses during the disease course. Both age at diagnosis and behavior were associated with different disease locations. Patients with ileal disease had a greater need for surgical and a lesser need for immunosuppressive treatment; patients with ileocolonic disease were diagnosed at an earlier age and showed a lower probability of remaining in remission during the disease course; patients with colonic disease needed less surgical or steroid treatments; patients with intestinal penetrating disease were frequently submitted to abdominal surgery, whereas those with anal-penetrating disease often needed immunosuppressive treatment. Approximately 40% of the patients were in clinical remission at any time, but only about 10% maintained a long-term remission free of steroids after their initial presentation. A more benign clinical course could be predicted in patients who stay in remission in the year after diagnosis. The grouping of patients with CD according to the Vienna Classification and/or the clinical activity in the year after diagnosis is useful in predicting the subsequent course of disease.  相似文献   
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