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81.
82.
R L Becker J F Norfray G P Teitelbaum W G Bradley J B Jacobs L Wacaser R L Rieman 《AJNR. American journal of neuroradiology》1988,9(5):885-889
Four patients with intracranial aneurysm clips made from a variety of alloys were studied without incidence by MR imaging at field strengths ranging from 0.35 to 0.6 T. Knowledge of the type of alloy used in the manufacturing of an aneurysm clip is important in determining whether the clip will or will not deflect in a magnetic field. Ferromagnetic clips show deflection and torque in a magnetic field and have the potential to dislodge from the aneurysm. Nonferromagnetic or weakly ferromagnetic aneurysm clips such as the Sugita (Elgiloy), Yasargil (316 LVM stainless steel), Heifetz (Elgiloy), Yasargil (Phynox), and Vari-Angle McFadden (MP35N) do not deflect or deflect weakly in the magnetic field and therefore would not be expected to dislodge during MR. The option of imaging many patients with intracranial aneurysm clips with MR extends the usefulness of the technique to a previously excluded population. 相似文献
83.
Infections of the developing brain. 总被引:1,自引:0,他引:1
L E Becker 《AJNR. American journal of neuroradiology》1992,13(2):537-549
84.
W Weidner W H Weiske J Rudnick H C Becker J Schroeder-Printzen E Br?hler 《Urologia internationalis》1992,49(1):24-28
Follow-up of patients 1 year after deep dorsal vein resection gives evidence of an approximate 50-60% success rate. A careful selection of only this small percentage of patients, in whom abnormal drainage through the penile dorsum is obvious, is mandatory. Men with an arterial cofactor have to be excluded or to be subsequently treated by intracavernosal autoinjection of vasoactive substances. Late results from our study demonstrate a further loss of sufficient erection, also in men considered as persistent success by us, in the subjective view of the patient and/or his sexual partner. 相似文献
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87.
The tripeptide N alpha-carbamoyl-L-methionyl-L-leucyl-L-phenylalanine methyl ester has been synthesized in solution by classical methods and fully characterized. This compound, prepared in order to obtain a deeper insight into the mode of binding at the formyl peptide chemotactic receptor, has been tested for its ability to induce granule enzyme secretion from rabbit peritoneal neutrophils and found to be a complete agonist. These results confirm the hypothesis that a proton on the N alpha-blocking group of the tripeptide forms a hydrogen bond with an acceptor in the binding site. 相似文献
88.
Success rate and duration of orthodontic treatment for adult patients with palatally impacted maxillary canines. 总被引:2,自引:0,他引:2
Adrian Becker Stella Chaushu 《American journal of orthodontics and dentofacial orthopedics》2003,124(5):509-514
This study was undertaken to examine the success rate and the length of orthodontic treatment of impacted maxillary canines in adult patients. A sample of 19 adults (mean age, 28.8 +/- 8.6 years; range, 20-47 years), who had been treated for a total of 23 impacted maxillary canines, was compared with a younger control group (mean age, 13.7 +/- 1.3 years; range, 12-16 years). The control subjects were chosen for a similar degree of impaction difficulty by carefully matching the positions of the impacted canines in the 3 planes of space. The success rate among the adults was 69.5% compared with 100% among the younger controls. The lower success rate was due to 5 canines that had failed to erupt and 2 canines that had been partially extruded but could not be aligned in the arch. The duration of treating the overall malocclusion of the adults and young subjects did not materially differ. However, the adults showed significant increases in the duration and number of treatment visits required for resolving the canine impaction, in both the simpler and the more difficult cases. When further divided by age, all the failed canines were found in the older (over 30) adult subgroup. It was concluded that the prognosis for successful orthodontic resolution of an impacted canine in an adult is lower than that in a younger patient and that the prognosis worsens with age. Furthermore, when such treatment is undertaken, its successful completion should be expected to take considerably longer. 相似文献
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90.