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Methods. The patterns and numbers of vascular anastomoses were checked on the placental surface, arterio-arterial (A-A) anastomosed vessels by ultrasound, and circulatory changes were studied with relation to uterine contraction.
Results. The high risk of monochorionic twin pregnancies was largely related to the patterns of vascular anatomy of the placenta and numbers of anastomosed vessels. The first placental vascular connection detected in vivo was the A-A anastomosis characterized by the bidirectional flow waveform in pulsed Doppler velocimetry.
Conclusion. TTTS is related to anastomosed vessels on the surface of placenta. To manage and prevent TTTS, fetal circulation and placental blood flow should be carefully observed. 相似文献
Methods. Late follow-up study was performed in the first consecutive 203 patients (mean age, 62.6 ± 9.1 years) who underwent isolated coronary artery bypass grafting with the left ITA anastomosed to the left anterior descending coronary artery and the right ITA to major branches of the circumflex artery. The patients were grouped according to the patency of ITA grafts demonstrated by early postoperative angiography (Both patent (BP) group, 168 patients: both ITAs showed complete patency; Not patent (NP) group, 23 patients: at least one ITA was dysfunctional).
Results. Actuarial 7-year survival in all patients was 89.3% ± 3.1%. The cumulative probability of event-free survival for cardiac death, myocardial infarction, intervention, and angina at 7 years was 96.6% ± 1.8%, 98.0% ± 1.5%, 86.7% ± 3.2%, and 90.7% ± 2.9%, respectively. NP group had more myocardial infarction and angina than the BP group, but was not statistically significant. Because of failed grafts at the early angiography, intervention was performed more frequently in NP group (p < 0.01).
Conclusions. Our results of actuarial 7-year survival and the cumulative probability of event-free survival were at least comparable to the results of other similar studies using bilateral ITA. The freedom from angina appeared to be better than in the previous study. Overall our study supports the continued use of this method of ITA grafting. 相似文献
Methods: A total of 34 136 men and 43 711 women aged 40–79 years were included in the study. The Cox proportional hazard model was used to estimate the relative risk (RR) and 95% confidence interval (95% CI) of oral and pharyngeal cancer for smoking and drinking by sex, while adjusting for age, consumption of green tea, preference for salty foods, and consumption of green yellow vegetables.
Results: Current smokers were found to have a higher risk of death caused by oral and pharyngeal cancer compared with non-smokers in both sexes: the RR was 2.6 (95% CI: 1.0–6.7) in men and 8.2 (95% CI: 2.1–32.1) in women. Men who drank more than 46 g ethanol per day had an approximately threefold increased risk of oral and pharyngeal cancer. Simultaneous exposure to both factors was significantly associated with an elevated risk of oral and pharyngeal cancer (RR: 3.3, 95% CI: 1.1–9.6).
Conclusions: The result supports the carcinogenic effect of cigarette smoking and alcohol drinking on the oral cavity and pharynx. 相似文献