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Early pregnancy complications: endovaginal sonographic findings correlated with human chorionic gonadotropin levels 总被引:2,自引:0,他引:2
Endovaginal sonography results were compared with quantitatively determined human chorionic gonadotropin (hCG) levels in 84 women referred for early pregnancy complications. Of the 27 with normal intrauterine pregnancies, an intrauterine gestational sac was prospectively identified in one of five cases (20%) in which hCG levels were below 500 IU/L (Second International Standard), four of five (80%) with hCG levels of 500-1,000 IU/L, and all 17 with hCG levels above 1,000 IU/L. In comparison, 17 of the 26 women with ectopic pregnancies (65%) had hCG levels greater than 1,000 IU/L, and none of the 26 had an intrauterine gestational sac. Endovaginal sonography demonstrated an adnexal mass and/or a gestational sac-like structure in 16 of the 17 cases (94%) in which hCG levels were above 1,000 IU/L, compared with only three of the nine (33%) with lower hCG levels (P less than .01). These findings indicate that an intrauterine gestational sac should be normally visualized with endovaginal sonography when the hCG level exceeds 1,000 IU/L, and that visualization of an extrauterine gestational sac and/or adnexal mass is significantly more likely in ectopic pregnancies when the hCG level exceeds 1,000 IU/L. 相似文献
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EUGENE V. POMERANTSEV M.D. ANTONIO COLOMBO M.D. FACC LOUIS DE LA FUENTE M.D. EBERHARD GRUBE M.D. CRAIG JUERGENS M.D. D. MATHEY M.D. Ph.D. M. SCHALIJ M.D. J. J. GOY M.D. M.C. MORICE M.D. J. SCHOFER M.D. IRAWAN SUGENG M.D. FACC SIMON H. STERTZER M.D. FACC FOR THE AVE MICRO STENT STUDY GROUP 《Journal of interventional cardiology》1998,11(2):101-106
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Thymic cysts in mediastinal Hodgkin disease 总被引:3,自引:0,他引:3
Three cases of proved thymic cysts associated with mediastinal Hodgkin disease are presented. Two illustrate regression of lymphoma with chemotherapy but persistence of thymic cysts. The third case demonstrates a thymic cyst in untreated Hodgkin disease. These cases suggest that such cysts are probably neither coincidental with nor a consequence of therapy but are probably related to initial thymic involvement by Hodgkin disease. 相似文献
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Synaptic vestibular inputs of antidromically identified motoneurons and internuclear neurons in the abducens nucleus were studied electrophysiologically and pharmacologically in the isolated brain of grass frogs (Rana temporaria). The prevailing response pattern of abducens motoneurons (AbMOT) following stimulation of the VIIIth nerve was crossed disynaptic excitation and uncrossed disynaptic inhibition. A few AbMOT (five of 46), however, exhibited uncrossed excitation instead of inhibition. Abducens internuclear neurons (AbINT), identified by antidromic activation following stimulation of the contralateral medial longitudinal fascicle, exhibited disynaptic response patterns to stimulation of the VIIIth nerve that were very similar in latency and rise time to those of AbMOT except for the absence of uncrossed disynaptic inhibition. Bath application of strychnine (50 μM), a glycine antagonist, blocked the uncrossed inhibitory vestibular input to AbMOT and AbINT completely and reversibly, whereas picrotoxin (100 μM), a GABA (γ-aminobutyric acid) antagonist, had no detectable effect on these disynaptic potentials. These results suggest glycine as the transmitter of inhibitory vestibular projections onto AbMOT and AbINT. The pharmacology of the excitatory vestibular input of these neurons was studied by electrical stimulation of the vestibular nuclear complex. Crossed monosynaptic excitatory inputs in AbMOT and AbINT were blocked completely by CNQX (6-cyano-7-nitroquinoxaline-2,3-dione) (10 μM), an antagonist of AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) receptors, indicating glutamatergic excitation. Comparison of these results with those in the cat suggests the presence of a basic horizontal vestibulo-ocular reflex that is very similarly organized, and corroborates the hypothesis that major behavioural differences in the performance of compensatory eye movements between species result from the properties of supplementary networks and not from differences in a common‘three-neuron’vestibulo-ocular arc. 相似文献
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