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Prenatal cytogenetic analysis of 71 fetuses conceived by intracytoplasmic sperm injection (ICSI) resulted in the detection of nine (12.7%) chromosome aberrations including two cases of 47,XXY, four cases involving a 45,X cell line and three autosomal trisomies. Molecular analysis of the parental origin of the deleted or supernumerary chromosome was performed by using polymorphic microsatellite markers. Six cases involving a sex chromosome abnormality were found to be of paternal origin while the two trisomic cases that could be analysed were of maternal origin. Two cases involved the same infertile couple who had two consecutive ICSI pregnancies terminated because of a chromosome abnormality. The replaced embryos in both cases originated from a single batch of ICSI fertilized oocytes of which part was used to initiate the first pregnancy and part was cryopreserved and used to initiate the second pregnancy.   相似文献   
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The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.  相似文献   
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The Phadebact(R) Gonococcus Test, a slide coagglutination test, was compared with the Difco fluorescent antibody test for the identification of Neisseria gonorrhoeae isolated from 18- to 24-hour primary plates. A total of 316 morphologically characteristic, oxidase-positive, Gram-negative diplococci were tested. Altogether 298 isolates were identified definitively as N. gonorrhoeae by a rapid carbohydrate utilisation test; 287 of the 298 isolates of N. gonorrhoeae were identified by the coagglutination test, a sensitivity of 96%. The sensitivity of the fluorescent antibody test was 85% (254 of 298 isolates). False-positive results due to cross-reactions with non-gonococcal Neisseria were uncommon (1 of 18 non-gonococcal isolates in the coagglutination test, a specificity of 94%; 2 of 18 in the fluorescent antibody test, a specificity of 88%). None of the 14 other contaminant organisms seen frequently on primary isolation media gave positive reactions. Interpretation of the coagglutination test proved to be difficult initially. Thirty-two (10%) coagglutination tests had to be repeated; 3 of the 32 (1% of the total isolates tested) remained uninterpretable.  相似文献   
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BACKGROUND: Positron emission tomographic studies of patients with Alzheimer disease (AD) suggest a loss of metabolic functional interactions between different cortical regions. Atrophy of the corpus callosum as the major tract of intracortical connective fibers may reflect decreased cortical functional integration in AD. OBJECTIVES: To investigate whether regional atrophy of the corpus callosum is correlated with regional reductions of cortical glucose metabolism, as shown by positron emission tomography, and whether primary white matter degeneration is a possible cofactor of corpus callosum atrophy in AD. PATIENTS AND METHODS: We measured total and regional cross-sectional areas of the corpus callosum on midsagittal magnetic resonance imaging scans from 12 patients with AD and 15 age-matched control subjects. Regional cerebral metabolic rates for glucose in cortical lobes were measured by positron emission tomography using fludeoxyglucose F 18. White matter hyperintensities were rated in T2-weighted magnetic resonance imaging scans. RESULTS: The total cross-sectional area of corpus callosum was significantly reduced in patients with AD, with the most prominent changes in the rostrum and splenium and relative sparing of the body of the corpus callosum. Frontal and parietal lobe metabolism was correlated with the truncal area of the corpus callosum in AD. The ratios of frontal to parietal and of frontal to occipital metabolism were correlated with the ratio of anterior to posterior corpus callosum area in the group with AD. White matter hyperintensities did not correlate with corpus callosum atrophy in the patients with AD. CONCLUSION: The regional pattern of corpus callosum atrophy correlated with reduced regional glucose metabolism independently of primary white matter degeneration in the patients with AD.  相似文献   
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-Adrenoceptor stimulation may induce malignant hyperthermia(MH) in vivo. Consequently, we have investigated the effectsof the -adrenoceptor agonist phenylephrine and, for comparison,the effects of the ß-adrenoceptor agonist isoproterenolon inositol-lipid metabolism of malignant hyperthermia susceptible(MHS) and healthy control (MHN) swine. The experiments wereperformed on electrically stimulated (frequency 0.2 Hz) trabeculaeisolated from the right ventricles of the hearts of MHS andMHN animals. After labelling with [3H] inositol for 6 h, differentinositol phosphates were measured by high pressure liquid chromatography,including inositol 1 - phosphate, inositol 1,4-bisphosphate,inositol 1,3,4-trisphosphate, inositol 1,4,5-trisphosphate (1,4,5-IP3)and inositol 1,3,4,5 - tetrakisphosphate. After stimulationwith isoproterenol, the inositol phosphate content did not increaseor vary between muscle from MHS and MHN animals. In contrast,all inositol phosphates increased after stimulation with phenylephrinein both muscle types, the effects being greater in MHS thanin MHN, especially as regards 1,4,5-IP3 content. As 1,4,5-IP3,a presumed second messenger, has been shown to mobilize intracellularcalcium, it is concluded that an enhanced -adrenergic responseis involved in the development of MH. *Address for correspondence: Abteilung für Anästhesiologie,Universitäts-Krankenhaus Eppendorf, Martinistrasse52, D-2000Hamburg 20, Germany. Presented in part at the 1989 Meeting of the European Academyof Anaesthesiology in Bonn.  相似文献   
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Summary Staining reactions for a number of histochemical procedures for lipophilic staining and protein were studied in the enamel matrix along the length of rat incisors. Sudan Black gave a positive stain across the whole thickness of very early enamel (up to 30 m) but this staining only continued as a narrow band close to the ameloblasts as the enamel matured. A variety of tests for protein produced almost identical staining patterns in enamel matrix up to 100 m thick. Since the pattern of lipid staining persisted, after using a number of procedures which could normally be expected to remove lipid, it is suggested that Sudan Black positive staining may be due to lipophilic protein rather than lipid itself. Fluoride did not significantly alter the staining reactions for lipid and protein but did proceduce matrix which was much more effectively stained by cross-linking agents FFDNB and FF sulphene.  相似文献   
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