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11.
This paper presents a patient successfully treated for leiomyosarcoma of the vena cava, with no recurrence or symptoms on an 8-year follow-up. A 56-year-old woman presented with chronic and progressive periumbilical and right upper abdominal pain. Physical examination and laboratory tests revealed no abnormalities. Computed tomography showed a high-density image inside the vena cava. Cavography showed a filling defect with complete occlusion of the vena cava involving the renal veins and greatly developed collateral circulation through lumbar veins. Laparotomy was performed and a large caval mass involving the renal veins was dissected and resected. Venous reconstruction was undertaken using a 19-mm bovine pericardium prosthesis (Labcor, MG-Brazil) interposed as a substitute to the vena cava, and the renal veins were anastomosed to the side of the graft. Pathologic examination confirmed a leiomyosarcoma with free surgical margins. The postoperative course was uneventful and the patient was discharged on postoperative day 8. The venous flow through the inferior vena became normal, as confirmed by later cavography. This paper presents a case of successfully managed leiomyosarcoma of the vena cava with a thorough review of the literature. The treatment of such patients and the use of bovine pericardium are also discussed.  相似文献   
12.

Background  

Health-related quality of life (HRQL) in persons with multiple sclerosis (MS) who reside within the community relative to the general population is largely unknown. Data from the Canadian Community Health Survey Cycle 1.1 (CCHS 1.1) were used to compare HRQL of persons with MS and the general population.  相似文献   
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Speaking involves the activity of multiple muscles moving many parts (articulators) of the vocal tract. In previous studies, it has been shown that mechanical perturbation delivered to one moving speech articulator, such as the lower lip or jaw, results in compensatory responses in the perturbed and other non-perturbed articulators, but not in articulators that are uninvolved in the specific speech sound being produced. These observations suggest that the speech motor control system may be organized in a task-specific manner. However, previous studies have not used the appropriate controls to address the mechanism by which this task-specific organization is achieved. A lack of response in a non-perturbed articulator may simply reflect the fact that the muscles examined were not active. Alternatively, there may be a specific gating of somatic sensory signals due to task requirements. The present study was designed to address the nature of the underlying sensorimotor organization. Unanticipated mechanical loads were applied to the upper lip during the "p" in "apa" and "f" in "afa" in six subjects. Both lips are used to produce "p", while only the lower lip is used for "f". For "apa", both upper lip and lower lip responses were observed following upper lip perturbation. For "afa", no upper lip or lower lip responses were observed following the upper lip perturbation. The differential response of the lower lip, which was phasically active during both speech tasks, indicates that the neural organization of these two speech tasks differs not only in terms of the different muscles used to produce the different movements, but also in terms of the sensorimotor interactions within and across the two lips.  相似文献   
16.
Centrilobular emphysema: CT-pathologic correlation   总被引:5,自引:0,他引:5  
Over a 5-year period, 25 patients who had undergone chest computed tomography (CT) died and were autopsied. Their lungs were fixed in the inflated state and were assessed for the presence and severity of centrilobular emphysema (CLE). Three radiologists independently evaluated the CT scans for nonperipheral low-attenuation areas, peripheral low-attenuation areas, pulmonary vascular pruning, pulmonary vascular distortion, and pulmonary density gradient. The CT criterion that best correlated with the presence and severity of CLE was the nonperipheral low-attenuation area. With this CT criterion, lung destruction was correctly identified in 13 of 15 cases. The absence of this criterion resulted in correct identification of eight of ten normal lungs. These preliminary data suggest that CLE can be reliably identified and quantified with current CT scanners.  相似文献   
17.
Transabdominal versus endovaginal pelvic sonography: prospective study   总被引:1,自引:0,他引:1  
Transabdominal and endovaginal pelvic sonograms were obtained in 108 nonpregnant patients referred for pelvic sonography. The studies were independently obtained by two radiologists and interpreted on the basis of identical clinical information. The sonograms were then compared for anatomic detail and abnormalities. A determination was made about which examination, if either, was superior. Follow-up was performed through a review of the medical records and follow-up studies. Overall, the endovaginal study was judged superior in 65 cases (60.2%), equal in 39 (36.1%), and inferior in four (3.7%). The authors conclude that the endovaginal examination can effectively replace the transabdominal examination as the initial approach for routine pelvic sonography.  相似文献   
18.
BACKGROUND: Asian Americans are generally underrepresented both as volunteer blood and bone marrow donors. STUDY DESIGN AND METHODS: To investigate the risk of transfusion transmission of viruses that is associated with increasing participation by Asian American donors, antibodies to human T-lymphotropic virus (HTLV), hepatitis C, and human immunodeficiency virus in Asian American volunteers recruited as potential bone marrow donors were measured. A total of 1354 Asian Americans were enrolled in the study, of whom 54 percent were Chinese, 26 percent Japanese, 9 percent Filipino, 4 percent Korean, 3 percent Indian, and 5 percent of other Asian or mixed Asian and other ethnicity. The majority of the study population was aged 20 through 49 and of high socioeconomic status, as indicated by education and income. Viral antibodies were measured with both screening enzyme-linked immunosorbent assays and supplemental testing, and polymerase chain reaction was used to resolve discrepant HTLV results. RESULTS: Confirmed seroprevalence rates for HTLV were 0.15 percent with one manufacturer's Western blot and 0.3 percent with the other; however, no sample was positive for HTLV types I or II in polymerase chain reaction. Confirmed seroprevalence to hepatitis C virus was 0.5 percent. No subject was seropositive for human immunodeficiency virus. CONCLUSION: On the basis of the moderate size and high education level of this study population, it is concluded that Asian American volunteer bone marrow donors do not pose a greater risk for transmission of HTLV type I or II, human immunodeficiency virus, or hepatitis C virus than does the average American blood donor.  相似文献   
19.
Different configurations of the Monticelli-Spinelli and Ilizarov external fixation systems were tested to define their mechanical properties. In five configurations the external fixator consisted of rings with tensioned wires (circular), while in one configuration two pairs of the tensioned wires and their correspondent ring were replaced by threaded pins (hybrid). Testing was performed in axial compression, bending and torsion. The results were compared to the characteristics of a selected linear fixator group. Both the circular and the hybrid configurations were non-linear in compression. In bending, circular fixators had a similar pattern in both anteroposterior and oblique loading directions. The bending load-displacement pattern for the hybrid fixators was similar to the linear fixators, higher stiffness in the plane of the pins. Torsion was linear for both circular and hybrid fixators, as for the linear fixators. By combination of wires and pins (hybrid configuration), the mechanical behaviour had characteristics from both linear and circular fixators. It is concluded that the three studied groups own different mechanical performance and can be considered as different types of fixators. While it has been demonstrated that osteogenesis can be achieved independently of the mechanical behaviour of the fixator, this study supports the suggestion that some complications can be related to the mechanical behaviour of the fixator.  相似文献   
20.
We investigated auditory and somatosensory feedback contributions to the neural control of speech. In task I, sensorimotor adaptation was studied by perturbing one of these sensory modalities or both modalities simultaneously. The first formant (F1) frequency in the auditory feedback was shifted up by a real-time processor and/or the extent of jaw opening was increased or decreased with a force field applied by a robotic device. All eight subjects lowered F1 to compensate for the up-shifted F1 in the feedback signal regardless of whether or not the jaw was perturbed. Adaptive changes in subjects' acoustic output resulted from adjustments in articulatory movements of the jaw or tongue. Adaptation in jaw opening extent in response to the mechanical perturbation occurred only when no auditory feedback perturbation was applied or when the direction of adaptation to the force was compatible with the direction of adaptation to a simultaneous acoustic perturbation. In tasks II and III, subjects' auditory and somatosensory precision and accuracy were estimated. Correlation analyses showed that the relationships 1) between F1 adaptation extent and auditory acuity for F1 and 2) between jaw position adaptation extent and somatosensory acuity for jaw position were weak and statistically not significant. Taken together, the combined findings from this work suggest that, in speech production, sensorimotor adaptation updates the underlying control mechanisms in such a way that the planning of vowel-related articulatory movements takes into account a complex integration of error signals from previous trials but likely with a dominant role for the auditory modality.  相似文献   
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