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31.
Objective  To evaluate the outcome of severely anaemic monochorionic (MC) twins surviving the death of their co-twin following early intrauterine rescue transfusion in cases of feto-fetal transfusion syndrome (FFTS).
Study design  We reviewed all MC pregnancies complicated with FFTS following primary management, in which a single intrauterine fetal death (IUFD) was diagnosed with certainty within 24 hours between January 1999 and December 2006. We included MC survivors who presented ultrasound or Doppler features of fetal anaemia following the death of their co-twin. Intrauterine transfusion (IUT) was given to all survivors who were anaemic.
Results  Nineteen MC twin pregnancies presented a single intrauterine death (IUD) associated with an anaemic co-twin. Median gestational age at IUD was 23 [20–28] weeks. The median interval between IUD and IUT was 12 [8–24] hours. There were 58% (11/19) healthy survivors. Perinatal death rate was 26% (5/19) including 16% (3/19) intrauterine and 10% (2/19) neonatal deaths. Abnormal prenatal cerebral findings developed in 21% (4/19) cases, always within 1 month after the death of the co-twin. Considering occlusive techniques and other management separately, there were 64% (7/11) and 50% (4/8) healthy survivors, respectively, and perinatal death occurred in 36% (4/11) and 12.5% (1/8) of fetuses, respectively. Prenatal fetal cerebral lesions developed in 9% (1/11) of cases following occlusive techniques and in 37.5% (3/8) of fetuses when managed differently. The median gestational age at delivery in the survivors was 31 [25–38] weeks.
Conclusion  In cases of FFTS with single anaemic survivors, early IUT could be offered following extensive counselling and close follow up.  相似文献   
32.

Objectives

To construct new reference charts and equations for birth weight and birth size using a large and exhaustive sample of newborns. To compare this new references with previous ones.

Materials and methods

The study data were obtained from a single health authority (the birth registry of Yvelines, a French Territorial division of 1.4 million people) over 3 years. Multiple pregnancies were excluded. No data were excluded on the basis of abnormal biometry or birth weight. For each measurement, a least square regression model with high order polynomials was fitted to predict mean, standard deviation and therefore Z scores of birth weigh and birth size at any gestational age at birth from 25 to 42 weeks'.

Results

There were 58 934 and 56 956 measurements included for weight and size at birth respectively. New charts and equations for Z scores calculations, adjusted for sex, are reported based on polynomial regression methods.

Conclusion

We present new French reference charts and equations for birth biometrics. Because they were derived from a very large and unselected sample, there might be more relevant to clinical practice than others and can be easily used to compute centiles and Z-scores.  相似文献   
33.
Adhesion barriers are intraperitoneal agents, solid or fluid, developed in order to prevent postoperative adhesions. In this article, we evaluate the efficiency of these new barrier agents for adhesion prevention in gynaecologic surgery, undertaking a review of controlled clinical trials published. Several human clinical trials demonstrated the safety and efficiency of both Interceed and Seprafilm. As far as other barrier agents are concerned, data are still insufficient to recommend them for clinical use. There is a need for other randomised controlled trials in order to evaluate functional efficiency of anti adhesion agents.  相似文献   
34.
Interactions between pregnancy and breast cancer are complex and paradoxical. Epidemiological data show that nulliparity and late full-term pregnancy increase breast cancer risk. By contrast, early full-term pregnancy and multiparity are thought to be the most effective means of decreasing lifetime breast cancer risk. Paradoxically, young women diagnosed with breast cancer during pregnancy have a higher risk of dying from their disease. Moreover, there is a transient increase in risk of breast cancer in the first three to four years after pregnancy. After breast cancer treatment, there is no evidence that pregnancy increases the risk of breast cancer recurrence. Thus, it is not contraindicated in women previously treated for breast cancer and free of recurrence. Various physio-pathological mechanisms are involved in the protective effect of pregnancy, like cellular differentiation of mammary cells, mammary gland involution, circulating anti-mucin antibody and excretion in the milk of breast carcinogens. In the past, unfavorable effects of pregnancy were mainly attributed to precancerous cell proliferation induced by pregnancy-associated hormonal changes. However, recent studies suggest that the remodeling of cellular microenvironment and extracellular matrix during pregnancy and involution may contribute to enhanced invasive and metastatic potential of breast carcinomas.  相似文献   
35.
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37.
OBJECTIVE: To determine trabecular and subchondral bone metabolic changes in experimental canine osteoarthritis (OA). METHODS: OA was induced in 19 dogs by transection of the anterior cruciate ligament (ACL) of the right knee through a stab wound. Dogs were sacrificed at 8 (n=7) and 12 weeks (n=12) after surgery. Non-operated normal dogs (n=6) were used as controls. After sacrifice, samples were obtained from the weight-bearing area of medial tibial plateaus. Explants and cell cultures were prepared from subchondral and trabecular bone. Osteocalcin (Oc), cellular alkaline phosphatase (ALPase), urokinase plasminogen-activator (uPA), prostaglandin E2 (PGE2), metalloproteinase (MMP) and nitric oxide (NO) were measured using standard procedures. RESULTS: ALPase production was significantly increased only at week 12 in subchondral and trabecular bone, while an increase in Oc was noted at week 8. uPA and MMP activity were increased significantly at week 12 in subchondral bone, while PGE2 levels were significantly higher in subchondral and trabecular bone at week 12 compared to normal. A decrease in NO production appeared late at week 12 in trabecular bone, whereas NO levels from subchondral bone were significantly increased compared to normal at week 8. DISCUSSION: Intense bone remodeling takes place in both subchondral and trabecular bone in the knee following ACL transection. This process seems to occur around week 12, although Oc and NO appeared to be involved earlier at 8 weeks. These results suggest that not only subchondral but also trabecular bone metabolism is altered in this OA model.  相似文献   
38.
39.
In the absence of thromboprophylaxis, coronary artery bypass graft surgery (CABG), intrathoracic surgery (thoracotomy or video-assisted thoracoscopy), abdominal aortic surgery and infrainguinal vascular surgery are high-risk surgeries for the development of venous thromboembolic events (VTE). The incidence of VTE following surgery of the intrathoracic aorta, carotid endarterectomy or mediastinoscopy is unknown. Data from the litterature are lacking to draw evidence-based recommandations for venous thromboprophylaxis after these three types of surgeries, and the following guidelines are but experts'opinions (Grade D recommendations). Thromboprophylaxis is recommended after CABG (Grade D), with either subcutaneous (SC) low molecular weight heparin (LMWH) or SC or intravenous (i.v.) unfractioned heparin (UH) (PTT target = 1.1-1.5 time control value) (both grade D). This may be combined with the use of intermittent pneumatic compression device (Grade B). After valve surgery. The anticoagulation recommended to prevent valve thrombosis is sufficient in order to prevent VTE. We recommend thromboprophylaxis with either LMWH or low dose UH to prevent VTE after aortic or lower limbs infrainguinal vascular surgery (both grade B and D). Vitamine K antagonists (VKA) are not recommended in this indication (Grade D). We recommend thromprophylaxis following intrathoracic surgery via thoracotomy or videoassisted thoracoscopy (grade C). Either subcutaneous LMWH or subcutaneous or i.v. low dose UH may be used (Grade C). Efficacy of intermittent pneumatic compression device has been demonstrated in a study (grade C). VKA are not recommended (grade D). No further recommendation regarding the duration of thromboprophylaxis after these three types of surgeries can be made.  相似文献   
40.

Objectives:

To determine the optimal CBCT settings for an automatic edge-detection-based endodontic segmentation procedure by assessing the accuracy of the root canal measurements.

Methods:

12 intact teeth with closed apexes were cut perpendicular to the root axis, at pre-determined levels to the reference plane (the first section made before acquisition). Acquisitions of each specimen were performed with Kodak 9000® 3D (76 µm, 14 bits; Kodak Carestream Health, Trophy, France) by using different combinations of milliamperes and kilovolts. Three-dimensional images were displayed and root canals were segmented with the MeVisLab software (edge-detection-based method; MeVis Research, Bremen, Germany). Histological root canal sections were then digitized with a 0.5- to 1.0-µm resolution and compared with equivalent two-dimensional cone-beam reconstructions for each pair of settings using the Pearson correlation coefficient, regression analysis and Bland–Altman method for the canal area and Feret''s diameter. After a ranking process, a Wilcoxon paired test was carried out to compare the pair of settings.

Results:

The best pair of acquisition settings was 3.2 mA/60 kV. Significant differences were found between 3.2 mA/60 kV and other settings (p < 0.05) for the root canal area and for Feret''s diameter.

Conclusions:

The quantitative analyses of the root canal system with the edge-detection-based method could depend on acquisition parameters. Improvements in segmentation still need to be carried out to ensure the quality of the reconstructions when we have to deal with closer outlines and because of the low spatial resolution.  相似文献   
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