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Magnetic resonance (MR) imaging of jugular venous thrombosis was investigated in three patients who had symptoms suggestive of this condition; the diagnosis was later confirmed by computed tomography, by venography, and clinically. Bright intraluminal signal intensity was seen throughout the course of the affected jugular vein on MR images in all three patients, in sharp contrast to the lack of signal from the corresponding site in the uninvolved venous system. Temporal changes in signal intensity from the acute to subacute stage of thrombosis were evaluated for one patient. A relative increase in signal intensity for the subacute phase was believed to be related to a decrease in the T1 relaxation time. MR may be the imaging modality of choice in the investigation of venous thrombosis. 相似文献
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Clinical application of human egg cryopreservation 总被引:20,自引:17,他引:3
Tucker MJ; Morton PC; Wright G; Sweitzer CL; Massey JB 《Human reproduction (Oxford, England)》1998,13(11):3156-3159
Clinical egg cryopreservation has been applied during a 4-year period with
some limited success. Mostly mature and a few immature eggs were frozen
slowly and thawed rapidly in 1,2-propanediol and sucrose, and subsequently
inseminated by intracytoplasmic sperm injection (ICSI). Three studies were
performed in which: (i) it was established that 55% of aged unfertilized
mature eggs survive freezing; (ii) in 22 cycles of thawed donated eggs
cryosurvival was 24% with 15 cycles reaching transfer, and five pregnancies
were initiated, one of which went to term at 39 weeks with fraternal twin
boys, and one remains ongoing at 37 weeks; and (iii) in five cycles, where
in-vitro fertilization patients had some of their own eggs frozen/ thawed,
cryosurvival of mature eggs was poor at only 2.2%, although 44% sibling
germinal vesicle (GV) stage eggs survived. A normal female infant delivered
at 40 weeks arose from transfer of two embryos where GV eggs underwent in-
vitro maturation post-thaw and were fertilized by ICSI. Pregnancies
reported here and by others indicate a burgeoning awareness of the
potential benefits of egg cryopreservation, prompting cautious optimism for
the future of this technology.
相似文献
116.
PC Ng TF Fok CH Lee KL Cheung CK Li KW So W Wong PMP Yuen 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(11):1197-1199
Two cases of homozygous α-thalassaemia who received active treatment in accordance with parental wishes are reported. One infant survived and the other, although successfully weaned off mechanical respiratory support, unexpectedly developed portal vein thrombosis and died. Homozygous a-thalassaemia, a condition previously considered to be universally fatal, and an indication for therapeutic abortion, is now potentially curable with advances in diagnostic technology and treatment. However, active management of these cases raises serious ethical questions and has major financial implications on the health-care system. Invasive prenatal and intensive postnatal interventions should remain experimental and cannot be recommended as routine clinical practice until the questions of long-term neurodevelopmental outcome, and the morbidity and mortality associated with bone-marrow transplantation have been fully addressed. As a result of advances in information technology, more and more parents of affected foetuses are likely to request active treatment. 相似文献
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