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91.
92.
A new concept, the motion axis of fracture (MAF), which is defined as the transitional point from anterior compressive to posterior splitting failure on a lateral radiograph, has provided a true understanding of the mechanisms of flexion-distraction injuries in clinical cases. This study was designed to produce in vitro injuries that have MAFs and to clarify the relation between the flexion angle and the MAF location. Adolescent porcine thoracolumbar spines were exposed to a vertical compressive load to failure at three different flexion angles and then examined radiographically. The MAF location was recorded as the distance from the anterior border to the MAF expressed as a percentage of the anteroposterior diameter of the vertebral body. All specimens showed similar injuries, with MAFs consisting of anterior compression fractures in the vertebral bodies and posterior disruptions. A significant negative correlation emerged between the flexion angle and the MAF location (r = -0.890; p < 0.0001). These results suggest that even a vertical compressive load contributes to the production of a flexion-distraction injury with an MAF in the thoracolumbar spine. They also indicate that the flexion angle of the spine at which the vertical compressive load is applied is an important factor in determining the MAF location; that is, the larger the flexion angle, the more anterior the MAF.  相似文献   
93.
We describe the occurrence of a supracellar ectopic pituitary adenoma in a 34 year old woman who presented with cranial diabetes insipidus and subsequently developed galactorrhoea-amenorrhoea. The tumour was demonstrated by both contrast computed tomography scan and magnetic resonance imaging with gadolinium enhancement and was confirmed at operation. Histological examination showed that the suprasellar lesion consisted of a pituitary adenoma while the pituitary biopsy revealed an unrelated pituitary microadenoma embedded in normal pituitary tissues. A review is made of the reported cases of ectopic pituitary adenomas.  相似文献   
94.
Thirty-five patients with sequential fractures of both hips were studied prospectively. The second hip fractures occurred more commonly if the patients were institutionalized, if they suffered from concomitant neurologic diseases such as previous stroke or Parkinsonism, or if there was biochemical evidence of osteomalacia. Twelve patients sustained the contralateral hip fracture within 12 months of the first one. There was a significant correlation between biochemical evidence of osteomalacia and early occurrence of the second hip fracture. Although rehabilitation was difficult for such patients, it was possible with a longer period of intensive physiotherapy; only three patients were not able to walk upon discharge from the hospital after the second hip fracture.  相似文献   
95.
Thirty-three children under age 20 with medulloblastoma, treated between 1962 and 1976, at the University of California and the Claire Zellerback Saroni Tumor Institute of Mount Zion Hospital, San Francisco, were retrospectively studied. A relationship between dose and local control rate was suggested by an improved five-year survival in those patients receiving doses greater than 5000 rads to the posterior fossa. The posterior fossa, either alone or with the spinal cord, was the most frequent site of failure. Results of re-irradiation for failure were encouraging and no significant complications were noted. A study of the effects of craniospinal irradiation on the hematopoietic and immune system demonstrated a marked decrease in the peripheral lymphocyte population at the completion of therapy and suggested a functional impairment of the remaining lymphocytes. Other side effects of irradiation included suppression of the hypothalamic-pituitary axis and one instance of brain necrosis. Current treatment policy and proposals for future modifications are discussed.  相似文献   
96.
The authors report the successful surgical treatment of their patient with posttraumatic aneurysm of the left ventricle. On the basis of the data reported in the literature and on their own experience, the authors consider this lesion absolute indication for surgery.  相似文献   
97.
Zusammenfassung Die Autoren haben die Lymphdrainage der Brustdrüse bzw. deren Veränderungen in Fällen von Mastopathie studiert. Sie haben bei diesen Patientinnen in den pectoralen und axillären Lymphknoten bzw. in den Lymphgefäßen eine markierte Lymphstauung beobachten können. Sie weisen darauf hin, daß das infolge der Lymphstauung entstandene Kollateralen-Netz bei carcinomatösen Fällen schon im Frühstadium eine weitläufige Metastasenbildung bedingen mag.
Changes in the lymph drainage in mastopathy
Summary The authors have studied the lymph drainage of the breast and changes occurring in cases of mastopathy. In these patients they observed marked lymphatic congestion in the pectoral and axillary lymph nodes and lymph vessels. They point out that it seems possible that as a result of the formation of a collateral net through lymphatic congestion, extensive spread of metastases of carcinoma can occur already at an early stage.
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The purpose of this study was to evaluate the incidence and durability of additional proximal cuffs during endovascular abdominal aortic aneurysm repair (EVAR). A retrospective review of 90 EVAR patients was conducted. Postoperative survival, proximal sealing zone-related complications, and secondary procedures were analyzed. Additional proximal cuffs were used in 11%. Their use did not affect postoperative survival (p = .58), type I endoleak rate (4.4%; p = .19), or the need for sealing zone-related secondary procedures (6.3%; p = .38) compared with patients without cuff placement but was related to a higher cumulative graft migration rate (2.2% overall p = .02). Two patients (2.5%; p = .79) underwent conversion to open surgery, both for proximal sealing zone-related complications. Application of proximal cuffs appears to be an effective intraoperative adjunctive procedure to achieve a proximal seal during EVAR, with favorable midterm results. However, the risk of late endograft migrations may be elevated in this group.  相似文献   
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