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91.
Adrenocorticotropic hormone controls infantile spasms independently of cortisol stimulation 总被引:1,自引:1,他引:0
Infantile spasms constitute a severe seizure disorder unresponsive to standard anticonvulsants. Both prednisone and adrenocorticotropic hormone (ACTH) have produced remission of seizures in some patients. The mechanisms of action of these hormones are not known. Eight infants with infantile spasms were treated with prednisone for 2 weeks. This controlled the seizures in two patients. In the remaining six patients, prednisone was continued and ACTH was added. This treatment produced cessation of spasms in four patients. Serum prednisone and cortisol were measured at a number of points during treatment. In infants receiving prednisone and then prednisone plus ACTH, serum cortisol was suppressed to about one-quarter of baseline levels with the initiation of prednisone, and remained suppressed during ACTH administration. We conclude that ACTH can exert its effect on infantile spasms in the setting of adrenal suppression, and can act without stimulating endogenous cortisol production. A CNS site of action is suggested and should be sought. 相似文献
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94.
Hybrid subtraction for improved arteriography 总被引:2,自引:0,他引:2
95.
Modified Japanese Medaka Embryo-Larval Bioassay for Rapid Determination of Developmental Abnormalities 总被引:2,自引:0,他引:2
Farwell A Nero V Croft M Bal P Dixon DG 《Archives of environmental contamination and toxicology》2006,51(4):600-607
The Japanese medaka (Oryzias latipes) early-life-stage bioassay (18-day test) provides a suitable laboratory model for the evaluation of toxicant impact. The
naturally high variability in the time to hatch for medaka embryos is, however, a major limitation in terms of the duration
of the test. In this study, the 18-day test was modified to use agitation to synchronize hatch and reduce time to hatch for
nonexposed embryos. Then, bioassays were conducted using two different complex mixtures (polycyclic aromatic hydrocarbons
(PAHs) and naphthenic acids (NAs)) to compare the sensitivity of the measurement endpoints using the 18-day standard protocol
(SP) and the modified protocol (MP). Agitation reduced time to hatch by one third or more and improved hatch success (100%).
The MP proved to be a more sensitive test method for the sublethal evaluation of a stressor (PAH mixture) that caused reduced
hatch length and induced signs of blue sac disease (BSD) including heart deformities, yolk sac–pericardial edema, and cranial–skeletal
deformities. In contrast, there was some variability in the sensitivity of the test methods for developmental endpoints for
the sublethal evaluation of a stressor (NA mixture) that had no effect on hatch length and was a weak inducer of signs of
BSD. Even though the sensitivity of the measurement endpoints were slightly more or less sensitive for the MP vs. SP depending
on the mixture tested, the MP using agitation is recommended as a cost-effective and rapid alternative for screening the sublethal
impact of toxicants on the early-life stages of fish. 相似文献
96.
Significant orbital trauma can result in orbital floor fractures with subsequent prolapse of the orbital contents into the paranasal sinuses. Prolapse of the periorbita can result in extraocular muscle entrapment, diplopia, enophthalmos, and even visual loss. Management of orbital floor fractures traditionally has been accomplished through transconjunctival and subciliary incisions. These approaches provide adequate visualization and cosmetically acceptable scars. Unfortunately, post-operative lid malposition can occur in a small percentage of cases. Another limitation is easy visibility of the posterior orbit, which often is obscured by prolapsed orbital fat. In light of these limitations, some surgeons have begun to evaluate an endoscopic approach to orbital floor fractures. The endoscopic approach offers a hidden incision, improved fracture visualization, and avoidance of post-operative eyelid malposition. This article reviews the indications, technique, and potential complications of endoscopic orbital blow-out fracture repair. 相似文献
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A hybrid digital subtraction angiography technique and noise-reduction algorithm were used to evaluate the carotid bifurcation. Temporal, hybrid, and reduced-noise hybrid images were obtained in right and left anterior oblique projections, and both single- and multiple-frame images were created with each method. The resulting images were graded on a scale of 1 to 5 by three experienced neuroradiologists. Temporal images were preferred over hybrid images (average score = 3.2 and 2.4, respectively). The percentage of nondiagnostic examinations, as agreed upon by two readers, was higher for temporal alone than temporal + hybrid (4 and 1, respectively). In addition, also by agreement between two readers, temporal + hybrid images significantly increased the number of bifurcations seen in two views (87%) compared to temporal subtraction alone (64%). 相似文献
100.