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71.
OBJECTIVE: To test the hypothesis that combined intracavernosal injection with vascular endothelial growth factor (VEGF) with adeno-associated virus-mediated brain-derived neurotrophic factor (AAV-BDNF) synergistically facilitates the neural regeneration and erectile function after cavernosal nerve injury. MATERIALS AND METHODS: Forty Sprague-Dawley male rats were randomly divided into five equal groups: eight had a sham operation while 32 had bilateral cavernosal nerve freezing followed by an immediate intracavernosal injection with either phosphate-buffered saline (PBS), VEGF, AAV-BDNF, or AAV-BDNF + VEGF. Erectile function was assessed by cavernosal nerve electrostimulation at 3 months, and samples of the major pelvic ganglia and penile tissue were evaluated histologically. RESULTS: In this animal model of impotence from nerve injury, the recovery of erectile function was greatest in those receiving AAV-BDNF + VEGF; the mean (sd) maximal intracavernosal pressure in this group was 87.2 (20.78) cmH2O, compared with 37.3 (11.39) for VEGF alone and 49.8 (29.58) for AAV-BDNF alone. No erectile dysfunction was identified in the sham group, with a pressure of 100.7 (22.70) cmH2O, while all treatment groups significantly outperformed the PBS (control) group, at 29.3 (13.52) cmH2O. Furthermore, all animals receiving monotherapy or combined treatment had more NADPH-diaphorase-positive nerve fibres than controls but less than in the sham group. CONCLUSION: Bilateral cavernosal nerve freezing causes erectile dysfunction with accompanying neurological changes. Intracavernosal injection with either VEGF or AAV-BDNF alone enhances nerve regeneration, with combined therapy (VEGF and AAV-BDNF) promoting neural and erectile recovery additively. 相似文献
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We describe the case of a 50-year-old male with a history of asthma and seizure disorder who presented with a 5-month history of dyspnea. The patient had been treated with multiple courses of antibiotics for presumed community-acquired pneumonia before being determined to have allergic bronchopulmonary aspergillosis (ABPA) by serologic and radiographic criteria. Inflammation resulting from this disease had potentiated a postobstructive pneumonia caused by Nocardia asteroides and Stenotrophomonas maltophilia. Therapy with corticosteroids, trimethoprim sulfa, and voriconazole failed to prevent subsequent destruction of the right upper lobe and the patient required surgical intervention. The discussion emphasizes the diagnostic criteria for ABPA including historic, serologic, and radiographic findings; staging, and treatment. Other possible diagnoses, such as invasive pulmonary aspergillosis, chronic necrotizing aspergillosis, and hyper-IgE syndrome are also briefly reviewed. 相似文献
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A 12-year-old girl presented with hemoptysis, fever and weight loss. She was initially diagnosed and treated for presumed tuberculosis and a lung abscess. Salmonella typhi was isolated from the abscess. Hydatid cyst was diagnosed at surgery. This is the first reported case of a pulmonary hydatid cyst infected with S. typhi. 相似文献
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AIM: Wire-guided localization (WGL) of clinically occult breast lesions is a well established technique. The aim of this study was to evaluate radio-guided localization (ROLL) within the breast screening service of a district general hospital. METHOD: The study group comprised 70 women who underwent ROLL under US and stereotaxis. This required an injection of Technetium-labelled colloidal albumen into the impalpable breast lesion. The women then proceeded to theatre, where localization was achieved with the use of a gamma probe. The lesion was identified by the presence of a high signal, caused by the injected isotope. The results of 70 consecutive cases in which a breast lesion was localized using ROLL were compared with the results of the latest 70 WGLs. RESULTS: All 140 lesions were successfully localized. However, the change in technique from WGL to ROLL offered significant benefits to patients. CONCLUSION: Our study demonstrated that ROLL is a practical and reliable localization technique. It can be implemented in hospital units without using valuable gamma camera time. The cost compares well with WGL. There is an improved cosmetic outcome for patients, and the very small quantity of radioactivity used is safe for both patients and staff. 相似文献
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Dental students at the Harvard School of Dental Medicine (HSDM) are required to pursue and complete research projects in order to obtain the doctor of dental medicine (D.M.D.) degree. The purpose of this study was to evaluate the effect of curriculum changes on a set of measurable outcomes related to research pursuits. This study was designed as a retrospective analysis of outcomes data from the period 1992-2002. The predictor variable was program format (non-PBL vs. PBL); the outcome variables were the percentage of students listed as authors on an IADR/AADR abstract during their tenure at HSDM and the percentage of students listed as first and/or presenting authors. Univariate statistics were computed for each class, and independent samples t-tests were used to compare the study groups with regard to our outcomes. For the majority of our outcomes, there was no statistically significant difference between the PBL and non-PBL groups, possibly due to sample size limitations. While the implementation of PBL at HSDM has not universally increased student productivity in research, it has not had an adverse effect either. It is possible that students in the PBL curriculum are nurturing other interests, such as community service, while retaining productivity in research. 相似文献
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Royzman D Recio L Badovinac RL Fiorellini J Goodson M Howell H Karimbux N 《Journal of periodontology》2004,75(5):679-684
BACKGROUND: Bleeding indices are used as a screen for periodontal disease activity, a measure of disease prevalence, and a measure of effectiveness in clinical trials. Bleeding on probing (BOP) is widely interpreted as a sign of disease activity whereas its absence is interpreted as both a sign and predictor of health. Aspirin use has become increasingly common in the prevention of cerebrovascular and cardiovascular diseases. Because of its anti-platelet activity, aspirin is a non-disease factor that has the potential to affect the appearance of BOP. The hypothesis being tested is that short-term aspirin use in doses of 81 mg and 325 mg will increase the number of bleeding sites in a population with gingivitis. METHODS: Fifty-four subjects were screened initially, those subjects with 20% to 30% whole mouth BOP were randomly assigned to one of three arms: placebo group, 81 mg aspirin group, or 325 mg aspirin group. Before and after exposure to the respective regimens, clinical parameters were measured on all the teeth: the plaque index was recorded at four sites per tooth, and probing depth and BOP were evaluated at six sites per tooth using an automated pressure-sensitive probe. RESULTS: The data obtained in this clinical trial were analyzed utilizing a linear regression analysis to control for confounding variables. The primary measure of interest was BOP in patients clinically demonstrating naturally occurring gingivitis. The results of this study indicate that while controlling for age, gender, and plaque, "low dose" 81 mg and "regular dose" 325 mg of aspirin demonstrated a statistically significant 5.30 (P = 0.001) and 4.13 (P = 0.010) increase from baseline, respectively, in percent BOP. CONCLUSION: Failure to consider the effects of aspirin on BOP could impair proper diagnosis and treatment planning for clinicians and introduce a significant confounding variable in research situations. 相似文献