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81.
82.
Gerald M. Rittenberg M.D. Stephen I. Schabel M.D. Ivan Vujic M.D. Hubert C. Meredith M.D. 《Skeletal radiology》1978,2(4):243-244
The angiographic analogue of the sunburst, (right angle) periosteal new bone formation in osteogenic sarcoma is described. The angiographic findings in this tumor and their relationship to the pathologic appearance are discussed. 相似文献
83.
With a protamine sulphate precipitation method, total and free cytosol AR was assayed in BPH and prostatic carcinoma tissue, in order to investigate possible differences in AR concentration that might relate to the histo-pathology of the tissue or to endocrine manipulation of the patients. Similar ranges of total cytosol AR concentrations were observed in BPH and untreated prostatic carcinoma, but the latter tended to have a higher proportion of apparently free sites. Moreover, the proportion of "free" sites in the untreated carcinoma tissue appeared to be related to the proportion of poorly differentiated carcinoma in the specimen. In patients whose endogenous androgen levels had been lowered by treatment, the proportion of free sites tended to be higher, but a considerable proportion of sites appeared to be still occupied. Carcinoma tissue from some estrogen-treated patients had high cytosol AR concentrations. It is suggested that, in some treated patients, androgens of adrenal origin may occupy some AR sites and that some carcinomas may contain a considerable concentration of nonfunctional AR. 相似文献
84.
W.T. Ivan Yeung Ting-Yim Lee Rolando F. Del Maestro Roman Kozak Thomas Brown 《Journal of neuro-oncology》1992,14(2):177-187
Summary We have developed an in vivo method of measuring the blood-brain transfer constant (K) of iopamidol and the cerebral plasma volume (Vp) in brain tumors using a clinical X-ray CT scanner. In patient studies, Isovue 300 (iopamidol) was injected at a dosage of 1 ml/kg patient body weight. Serial CT scans of the tumor site and arterial blood samples from a radial artery were taken up to 48 min after injection. The leakage of iopamidol into the brain through the blood-brain barrier was modelled as an exchange process between two compartments, the intravascular plasma space and the tissue interstitial space. Using this model and the concentration measurements in blood plasma and tissue, quantitative estimates of K and Vp in brain tumors were obtained. In addition, distribution of the estimated values of K and Vp in tumors were displayed as false colour functional images overlaid on the conventional CT scan.In a study of twelve patients with anaplastic astrocytoma (n = 3), glioblastoma multiforme (n = 4) or metastases (n = 5) the mean K and VP values in tumor were found to be 0.0273 ± 0.0060 ml/min/g and 0.068 ± 0.11 ml/g respectively. These values were significantly higher than those in grey or white matter in the contralateral normal hemisphere (p < 0.05). The functional images showed variations in K and Vp within the tumor which were difficult to perceive in the original contrast enhanced CT scans. 相似文献
85.
Nine depressive patients were examined before bilateral electroconvulsive therapy (ECT), immediately after ECT, and 2 days later with saccadic, pursuit tracking, and Hallpike caloric vestibular tests. Before ECT, all tests showed normal results. Immediately after ECT, the saccadic test displayed dysmetria of the fast eye movements in six of nine patients. The pursuit tracking test showed decreased gain of the slow eye movements with compensatory saccades in seven of nine patients. These findings were for both directions in the horizontal plane. In the caloric vestibular test, the changes were not significant. Two days after ECT, the eye coordination and vestibular testing showed normal function. We conclude that the eye coordination and vestibular function disturbances induced by ECT are transient. 相似文献
86.
Evaluation of oxygen saturation monitoring by pulse oximetry in neonates in the delivery system 总被引:1,自引:0,他引:1
Ivan Dimich Prithi Pal Singh Alvin Adell Michele Hendler Norman Sonnenklar Mennakshi Jhaveri 《Journal canadien d'anesthésie》1991,38(8):985-988
The pulse oximeter was evaluated for use in neonates in the delivery room. One hundred neonates, delivered vaginally or by Caesarean section with general or epidural anaesthesia, were studied. After delivery, pulse oximetry probes were placed simultaneously on the ulnar side of the right hand and on the right Achilles tendon to determine whether there was a difference in arterial oxygenation (SpO2). Measurements of SpO2 were taken at 1, 5, 10 min, and 24 hr after delivery. At one and five minutes, SpO2 recorded from the right hand was higher than that recorded from the lower extremities (71.9% +/- 6.5% vs 63.4% +/- 4.3% and 83.3% +/- 4.2% vs 76% +/- 4.1%, mean +/- SD, respectively). At ten minutes these differences diminished, and had almost completely disappeared after 24 hr. These results can be explained by the presence of R-L shunting at the ductus arteriosus level, producing reduced SaO2 in the lower extremities. Oxygen saturation did not differ between neonates delivered vaginally or by Caesarean section, regardless of the presence or type of anaesthesia. We concluded that neonates remain relatively desaturated in the immediate postpartum period and that the SpO2 obtained from the right hand is a better index of neonatal oxygenation than that obtained from the heel. 相似文献
87.
88.
89.
The frequency of the hand trauma involving tissue losses generated the research for developing new technical solutions more simple and economic. The regional flaps, such as the distal pedicle Chinese flap, are usually surgeon's first choice whenever the local resources are over passed. Still, this type of Chinese flap would claim a major disadvantage as they involve the sacrifice of a vascular axis of the hand, sometimes even the dominant one. The operating team, would be able to avoid this inconvenience when using distal perforators based-on antibrachial radial flap; moreover, this technique would allow the covering of the substance losses, as far as the metacarpophalangeal joints. The authors report a clinical case. 相似文献
90.
A position paper on the subject of certified surgical specialists was published in 1966 under the direction of Professor
Charles Wells of Liverpool, England. President John Terblanche of the International Federation of Surgical Colleges brought
together leaders in surgical education from four nations (Australia, Japan, South Africa, United States) to update current
“state-of-the art” views. Presentations were made at the 38th Congress of the International Society of Surgery, August 18,
1999 in Vienna, Austria. After careful review of the four presentations, it was clear that surgeons all over the world have
made great improvements in the many facets of surgical education. Yet the advances remain spotty, with gaps noted when viewed
from an international perspective. 相似文献