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1.
In secondary mitral regurgitation, the concept that the mitral valve (MV) is an innocent bystander, has been challenged by many studies in the last decades. The MV is a living structure with intrinsic plasticity that reacts to changes in stretch or in mechanical stress activating biohumoral mechanisms that have, as purpose, the adaptation of the valve to the new environment. If the adaptation is balanced, the leaflets increase both surface and length and the chordae tendineae lengthen: the result is a valve with different characteristics, but able to avoid or to limit the regurgitation. However, if the adaptation is unbalanced, the leaflets and the chords do not change their size, but become stiffer and rigid, with moderate or severe regurgitation. These changes are mediated mainly by a cytokine, the transforming growth factor‐β (TGF‐β), which is able to promote the changes that the MV needs to adapt to a new hemodynamic environment. In general, mild TGF‐β activation facilitates leaflet growth, excessive TGF‐β activation, as after myocardial infarction, results in profibrotic changes in the leaflets, with increased thickness and stiffness. The MV is then a plastic organism, that reacts to the external stimuli, trying to maintain its physiologic integrity. This review has the goal to unveil the secret life of the MV, to understand which stimuli can trigger its plasticity, and to explain why the equation “large heart = moderate/severe mitral regurgitation” and “small heart = no/mild mitral regurgitation” does not work into the clinical practice.  相似文献   
2.
Congenital malformations after intracytoplasmic injection of spermatids   总被引:2,自引:0,他引:2  
Spermatid microinjection into oocytes was applied in cases of intracytoplasmic sperm injection (ICSI)/testicular sperm extraction (TESE) where no spermatozoa could be found in numerous testicular samples. Although several pregnancies were obtained with this procedure, serious concerns remain regarding its safety. Although the relevance of the injection of spermatids is by no means certain, we wish to report that from four pregnancies obtained after injection of elongated spermatids, two cases of major malformation resulted.  相似文献   
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OBJECTIVE: To assess (1) pulmonary artery and peripheral pulmonary blood flow by using a multigate spectral Doppler system and standard pulsed color Doppler ultrasonography and (2) the reproducibility of peripheral pulmonary artery blood flow velocity waveforms. METHODS: Thirty-three women were enrolled in the study Fetal pulmonary artery flow velocity waveforms were investigated by multigate spectral Doppler scanning and traditional pulsed Doppler ultrasonography plus color flow mapping. To establish the relationship between these 2 methods, we calculated the correlation coefficient, coefficient of variation, and limits of agreement. RESULTS: The 2 methods were not significantly correlated. The range of measurement agreement for these 2 methods suggests that there is a significant difference between the main and peripheral pulmonary artery blood flow, and the difference should be taken into account in the interpretation of Doppler flow velocity studies of the pulmonary artery. CONCLUSIONS: Multigate spectral Doppler scanning with power Doppler imaging may be a better way to assess the average flow impedance in a highly vascularized organ. This technique supplies a large number of Doppler signals in the region of interest and offers a quantified range of Doppler measurements, improving our understanding of fetal hemodynamics.  相似文献   
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BACKGROUND: The use of ultrasound-guided embryo transfer has been reported to affect success rates in some centres but not others. In a prospective study, we examined the influence of ultrasound guidance in embryo transfer performed on different days after oocyte retrieval. METHODS: Two different methods of embryo transfer were evaluated in 1069 consecutive transfers. The ultrasound-guided embryo transfer was used in 433 cases, whereas 636 embryo transfers were performed with the tactile assessment ('clinical feel') method. RESULTS: Ultrasound-guided embryo transfer yielded a higher overall pregnancy rate than the 'clinical feel' approach, 47 versus 36% (P < 0.001). This difference was statistically significant where embryos were transferred after 3 or 4 days of culture, 45.9 versus 37.1% (P = 0.001) and 42.3 versus 27% (P = 0.035) respectively but not significant (P = 0.112) on day 5 embryo transfer (56.3 versus 45.7%). Likewise, the implantation rate was significantly different between the two groups on day 3 and 4 embryo transfer, 23.3 versus 15.8% (P < 0.01) and 21.6 versus 15.7% (P < 0.05%) respectively but no statistical difference was noted on day 5 embryo transfer, 26.7 versus 23.6%. CONCLUSION: Ultrasound assistance in embryo transfer on day 3 and 4 significantly improved pregnancy rates in IVF but had no impact on day 5.  相似文献   
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We report the case of a cervical pregnancy successfully treated with intramuscular injection of methotrexate(MTX) and intramniotic administration of potassium chloride. A 41-year-old woman was admitted to our Department with the suspicion of ectopic pregnancy. Transvaginal ultrasound revealed empty endometrialcavity, gestational sac within the cervical canal and embryonic echo measuring crown rump length 1.5 mm. Serum beta human chorionic gonadotropine(β-HCG) was measured 28590 IU/L. No cardiac activity was detected. The diagnosis of a cervical pregnancy was made. Patient was treated with intramuscular administration of methotrexate(50 mg/m2) in combination with ultrasoundguided intramniotic injection of KCl(2 meq/mL). Gradual decrease of β-HCG levels as well as ultrasound observation of collapsed gestational sac was observed. No curettage was necessitated. Patient was discharged on day 10 th and was set in follow-up on a weekly basis. β-HCG values were measured 10 IU/L on 56 th day after MTX administration. Intramuscular administration of MTX may be effective in treatment of cervical pregnancy without additional interventional measures.  相似文献   
9.

Objective

To compare the efficacy of the long GnRH agonist and the fixed GnRH antagonist protocols in IVF poor responders.

Study design

This was a randomized controlled trial performed in the Iakentro IVF centre, Thessaloniki, from January 2007 to December 2011, concerning women characterised as poor responders after having 0–4 oocytes retrieved at a previous IVF cycle. They were assigned at random, using sealed envelopes, to either a long GnRH agonist protocol (group I) or a GnRH antagonist protocol (group II).

Results

Overall 364 women fulfilled the inclusion criteria and were allocated to the two groups: finally 330 participated in our trial. Of these, 162 were treated with the long GnRH agonist protocol (group I), and 168 with the fixed GnRH antagonist protocol (group II). Numbers of embryos transferred and implantation rates were similar between the two groups (P = NS). The overall cancellation rate was higher in the antagonist group compared to the agonist group, but the difference was not significant (22.15% vs. 15.2%, P = NS). Although clinical pregnancy rates per transfer cycle were not different between the two groups (42.3% vs. 33.1%, P = NS), the clinical pregnancy rate per cycle initiated was significantly higher in the agonist compared to the antagonist group (35.8% vs. 25.6%, P = 0.03).

Conclusions

Although long GnRH agonist and fixed GnRH antagonist protocols seem to have comparable pregnancy rates per transfer in poor responders undergoing IVF, the higher cancellation rate observed in the antagonist group suggests the long GnRH agonist protocol as the first choice for ovarian stimulation in these patients.  相似文献   
10.

Objective

To investigate the impact of operator experience on amniocentesis-related adverse outcomes.

Study design

Retrospective study of mid-trimester amniocenteses performed by the same operator on singleton pregnancies in a single private institution during 1994–2007. Outcomes were hemorrhagic or dark amniotic fluid aspiration, insufficient volume aspiration, repeated puncture and fetal loss. Rates were estimated annually, as well as for every 10% of procedures up to the total number. The association of each outcome with epidemiological aspects was also examined.

Results

In total, 5913 amniocenteses were performed. The overall rate of adverse outcomes was 5.4%. The total adverse outcome rate reduced from 10.2% in the first 10% of cases to 3.0% in the last 10% (P = .001). The rate of hemorrhagic fluid gradually decreased from 4.4% to 1.5% (P = .05) over the same intervals. The fetal loss rate was also reduced from 0.5% during the first half to 0.3% in the second half of the study period (P = NS). Logistic regression analysis indicated no significant correlations between adverse outcomes with any of epidemiological parameters of women undergoing amniocentesis.

Conclusion

Operator experience has a beneficial impact on preventing procedure-related adverse outcomes.  相似文献   
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