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81.
Factors affecting the surgical management of infective endocarditis   总被引:1,自引:0,他引:1  
Congestive heart failure and septic embolism complicate the clinical course of patients with infective endocarditis (IE). This study reviews the clinical records of patients with systemic disease secondary to IE and stratifies their disease severity according to individual risk factors and medical, and surgical interventions. The hospital records of all patients presenting to our institution from 1992 through 1997 with heart valve destruction secondary to IE were reviewed. Ten patients with hemodynamically significant valve lesions were included in this study: seven with aortic valve disease and two with mitral valve disease, and one with combined aortic and mitral valve lesions. All were diagnosed by echocardiogram. All ten patients experienced systemic septic arterial emboli: four intracranial lesions, four visceral lesions, and three extremity arterial occlusive events. Two patients required peripheral arterial repair. Cultures revealed infection secondary to Staphylococcus aureus in five, Streptococcus species in three, Coxiella species in one, and an unidentified organism in one patient. Seven patients underwent valve replacement. Three patients died from their disease processes. Statistical significance was established by Wilcoxon rank analysis with a two-tailed P < 0.05. Patients with IE secondary to staphylococcal infections suffered a more acute and virulent disease process (P = 0.04), with a 40 per cent mortality rate in the first 48 hours. There was no increased incidence of embolization associated with longer duration of symptoms (P = 0.32). Surgical repair conferred improved clinical outcome as compared with no surgical intervention (P = 0.03). Improved patient outcome was associated with nonstaphylococcal infection (P = 0.02), and a successful initial antibiotic regimen (P = 0.03). Peripheral arterial repair was successful in both cases.  相似文献   
82.
We describe the appearance of an adrenal neuroblastoma associated with tumor thrombus occurring in an adult patient. The tumor measured 14 x 12 x 12 cm, showed heterogeneous signal intensity on both T1-weighted and T2-weighted images, and displayed peripheral nodular enhancement on early post-gadolinium images. Tumor thrombus was identified within the inferior vena cava, which extended into the right atrium.  相似文献   
83.
Patient-centeredness and its correlates among first year medical students   总被引:4,自引:0,他引:4  
OBJECTIVE: This research was performed to study the attitudes that medical students hold concerning their relationships with patients, and whether such attitudes are gender-related, affect career plans, and influence their evaluation of psycho-social and biomedical issues. METHODS: One hundred fifty-three first year students at the Boston University School of Medicine completed the Patient-Practitioner Orientation Scale (PPOS), a scale that differentiates between a patient-centered vs. doctor-centered orientation toward medical practice, indicated their interest in community and primary care practice, and rank ordered psycho-social and biomedical clinical issues in terms of their perceived relative importance. RESULTS: The data revealed that female medical students were more patient-centered, and that (across sexes) patient centeredness was positively associated with an interest in community and primary care practice and the ranking of psycho-social issues. CONCLUSIONS: These findings indicate that differences in the practice attitudes of males and females exist very early on in medical training, and that these differences are associated with anticipated career choices. They also suggest that the PPOS may prove useful in measuring the attitudes of practicing physicians toward their clinical roles and might predict physicians' behavioral strategies and patient medical outcomes.  相似文献   
84.
Sertoli cells enhance the survival of co-transplanted dopamine neurons   总被引:5,自引:0,他引:5  
One of the major issues in neural transplantation is the low survival rate (<5%) of transplanted dopamine (DA) neurons [3]. Recently it has been shown that it is possible to enhance the survival of these neurons, which in turn may decrease the amount of tissue that is required for each transplantation patient. The present paper demonstrates a novel approach for enhancing neuronal survival by co-transplantation of neuronal tissue with Testis-derived Sertoli cells (SC). This strategy could improve neuronal survival through the provision of trophic support.  相似文献   
85.
Areas beyond the classical receptive field (CRF) can modulate responses of the majority of cells in the primary visual cortex of the cat (). Although general characteristics of this phenomenon have been reported previously, little is known about the detailed spatial organization of the surrounds. Previous work suggests that the surrounds may be uniform regions that encircle the CRF or may be limited to the "ends" of the CRF. We have examined the spatial organization of surrounds of single-cell receptive fields in the primary visual cortex of anesthetized, paralyzed cats. The CRF was stimulated with an optimal drifting grating, whereas the surround was probed with a second small grating patch placed at discrete locations around the CRF. For most cells that exhibit suppression, the surrounds are spatially asymmetric, such that the suppression originates from a localized region. We find a variety of suppressive zone locations, but there is a slight bias for suppression to occur at the end zones of the CRF. The spatial pattern of suppression is independent of the parameters of the suppressive stimulus used, although the effect is clearest with iso-oriented surround stimuli. A subset of cells exhibit axially symmetric or uniform surround fields. These results demonstrate that the surrounds are more specific than previously realized, and this specialization has implications for the processing of visual information in the primary visual cortex. One possibility is that these localized surrounds may provide a substrate for figure-ground segmentation of visual scenes.  相似文献   
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PURPOSE: To evaluate the clinical treatment efficacy of a long-lasting intravitreous injectable anti-cytomegalovirus (CMV) liposomal drug, 1-O-octadecyl-sn-glycerol-3-phosphonoformate (ODG-PFA). METHODS: Sixty-four pigmented rabbits were used for evaluation of the potency and duration of action of ODG-PFA after intravitreal injection using a herpes simplex virus (HSV)-1 retinitis model. For the potency evaluation, liposomal ODG-PFA was injected into rabbit vitreous at the same time that HSV-1 virus was inoculated onto the retina (simultaneous treatment). For the duration evaluation, ODG-PFA was injected days or weeks before inoculation (pretreatment). Retinitis was clinically graded by indirect ophthalmoscopy, and the retinitis scores were compared across the treatment and control groups. RESULTS: Simultaneous treatment study revealed that ODG-PFA was much more potent than its parent compound, foscarnet (P = 0.0027). Pretreatment study indicated that ODG-PFA possesses a much longer antiviral effect (at least 2 weeks) than foscarnet after a single intravitreal injection. CONCLUSION: Liposomal ODG-PFA is a potent long-lasting intravitreal injectable antiviral compound that may be an ideal alternative for treatment of CMV retinitis in patients with acquired immunodeficiency syndrome.  相似文献   
90.
PURPOSE: A visual pattern was broken into patches, some of which were shown to one eye and the remainder of which were shown to the other eye. Our aim was to find the conditions under which the subject could combine the information given to the two eyes separately to reconstruct the original pattern. METHODS: One green and four red patches were presented to one eye. Five patches were presented to the other eye at corresponding locations but with red substituted for green and green for red. RESULTS: When the chromatic contrasts were appropriately adjusted, subjects saw five patches of a single colour for most of the viewing time. Intermixed horizontal and vertical gratings did not separate into coherent percepts in the same way. CONCLUSIONS: This result indicates cooperation between the responses to colour patches presented to different eyes, a finding that may be of use in testing for normal binocular vision.  相似文献   
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