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1.
W R Nemzek H A Brodie B W Chong C J Babcook S T Hecht S Salamat W G Ellis J A Seibert 《AJNR. American journal of neuroradiology》1996,17(8):1467
PURPOSETo trace the development of the normal fetal temporal bone by means of plain radiography, MR, and CT.METHODSEighteen formalin-fixed fetal specimens, 13.5 to 24.4 weeks'' gestational age, were examined with a mammographic plain film technique, CT, and MR imaging at 1.5 T. Temporal bone development and ossification were assessed.RESULTSThe membranous labyrinth grows with amazing rapidity and attains adult size by the middle of the gestation period. The cochlea, vestibule, and semicircular canals are very prominent and easily recognized on MR images. The otic capsule develops from a cartilage model. Ossification of the otic capsule proceeds rapidly between 18 and 24 weeks from multiple ossification centers that replace the cartilaginous framework. The mastoid, internal auditory canal, vestibular aqueduct, and external auditory canal continue to grow after birth.CONCLUSIONThe study of fetal developmental anatomy may lead to a better understanding of congenital disorders of the ear. Faster MR scanning techniques may provide a method for in utero evaluation of the fetal temporal bone. 相似文献
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The greenbottle fly Lucilia sericata is an insect of great forensic interest for estimating the postmortem interval. The present study investigated the influence of methadone on the development of Lucilia sericata larvae. The results of the study showed a significant acceleration of larval development between day 3 and 5 when methadone is present in the food source. The total development times where shortened by up to 15 h in the group with therapeutic and toxic methadone concentrations. These results should be considered when undertaking forensic entomological examinations. 相似文献
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MGC Hendriks P Dogterom JT Ebels B Oosterhuis LR Geertsema T Hulot G Bianchetti and JHG Jonkman 《Fundamental & clinical pharmacology》1998,12(5):559-565
Summary— In the present study we have compared the steady state biopharmaceutic characteristics of four diltiazem once daily controlled release capsules: Mono-Tildiem LP 300® (300 mg), Adizem® XL (300 mg)1, Cardizem® (300 mg) and Dilacor® (240 mg). Sixteen healthy male volunteers (aged 22.9 ± 3.3 years, range 19–31 years) completed an open label, multiple oral dose, randomized, four-period crossover study without a washout period in between. The volunteers received each diltiazem formulation once daily for four days. Trough diltiazem and metabolites plasma concentrations were determined on days 3 and 4. The 24-h plasma concentration-time profiles were assessed after the dose on day 4 of each period. The following steady state pharmacokinetic parameters for diltiazem were calculated: the minimum plasma concentration (cmin), the maximum plasma concentration (cmax), the time to reach that concentration (tmax), the time interval during which the plasma concentration exceeds 50% of cmax (t50), the area under the plasma concentration-time curve (AUC72–96) and the peak-to-trough fluctuation (PTF). For the metabolites of diltiazem, N-mono-desmethyl-diltiazem (NDM) and desacetyldiltiazem (DAD), AUC72–96 (AUCNDM and AUCDAD) and the ratio metabolite/parent compound were calculated. Steady state was achieved on day 3. Except one, all controlled release formulations have satisfactory controlled release properties allowing once daily administration. However, significant (P < 0.05) differences were found between the pharmacokinetic characteristics which do not allow exchange of the various formulations. Concentrations well below 50 ng·mL-1 in the morning hours were observed for Dilacor® (240 mg) and Adizem® XL (300 mg), which could be a disadvantage of these formulations as it is well-known that ischaemic events occur at a higher rate during that part of the day. The plasma concentration profiles of NDM and DAD, the major circulating metabolites, parallel the plasma concentration profiles for the parent compound. From a clinical point of view, all treatments were well tolerated. 相似文献
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E Wachtel E Koplik I A Kolometsewa H U Balzer K Hecht P Oehme V T Ivanow 《Die Pharmazie》1987,42(3):188-190
In the present paper the effects of substance P (SP1-11, Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-MetNH2) and delta sleep inducing peptide (DSIP, Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu) to normalize the deprivation of sleep in chronically stressed rats with hyposomnia were investigated. The results indicated that SP1-11 is more potent than DSIP in rats with stress-induced hyposomnia. Different effects were found in the duration of sleep, the percentage of sleep phases compared to wake phases, the rhythm of sleep phases and the time periods of sleep-cycles. Based on the present results both the common and differences in the mode of action were discussed. 相似文献
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Jacqueline T. Hecht Nora M. Thompson Tempa Weir Larry Patchell William A. Horton 《American journal of medical genetics. Part A》1991,41(2):208-211
Thirteen infants with achondroplasia underwent psychometric testing as part of a comprehensive neurologic assessment. As a group, mental development was average and motor development was delayed, although a wide range of scores was obtained. Foramen magnum measurements were correlated with respiratory dysfunction, abnormal so-matosensory evoked potentials, and delayed motor development. Abnormal polysomno-gram outcome was associated with reduced mental capacity. In light of the reported increased frequency of respiratory dysfunction in achondroplasia, these findings warrant careful attention and further study. 相似文献
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W A Horton J T Hecht O J Hood R N Marshall W V Moore J G Hollowell 《American journal of medical genetics》1992,42(5):667-670
A pilot study was carried out to examine the safety and efficacy of recombinant human growth hormone for growth-promoting therapy of achondroplasia. The data suggest that the agent in doses used to treat non-GH-deficient forms of short stature (0.3 mg/kg/wk) modestly increases overall height velocity in some children with achondroplasia. The effect was seen mainly in children with the lowest growth velocities prior to treatment. No untoward effects were noted. Several questions were raised that require further study. 相似文献