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22.
Despite a significant improvement in the US maternal mortality ratio since the early 1900s, it still represents a substantial and frustrating burden, particularly given the fact that - essentially - no progress has been made in most US States since 1982. Additionally, the US Centers for Disease Control and Prevention has stated that most cases are probably preventable. Two disheartening issues within this topic include a gross underestimation of the magnitude of maternal mortality - particularly before 1987, but which likely persists to a lesser degree today - and the continued significant racial disparity in maternal mortality. Explanations for the plateau in maternal mortality include the recent trend of delayed childbearing, with the potential accompanying complications associated with older reproductive age (particularly over 35 years) and multiparity. The impressive increase in multifetal pregnancies related to delayed childbearing and assisted reproductive technology also plays a role. Finally, peripartum cardiomyopathy has become an increasingly recognized source of maternal mortality. Pregnancy-related mortality is largely accounted for by thromboembolic disease, hemorrhage, hypertension and its associated complications, and infection. However, since the inclusion of maternal deaths occurring after 42 days post-delivery as pregnancy related, traumatic injuries - including homicides and suicides - are an alarming source of maternal mortality. An especially important contemporary issue to consider within this topic is cesarean delivery "on maternal request", opponents of which cite concerns not only for immediate morbidity and mortality increased over that associated with a vaginal birth, but also for potential morbidity and mortality associated with future pregnancies. One particularly appealing opportunity to reduce maternal mortality is to recognize, examine, and learn from so-called "near-miss" cases.  相似文献   
23.
Galea P  Barigye O  Wee L  Jain V  Sullivan M  Fisk NM 《Placenta》2008,29(8):734-742
The renin-angiotensin system (RAS) in twin-twin transfusion syndrome (TTTS) is up-regulated in the donor fetus's kidneys, but down-regulated in the recipient's. Ultrasonographic and echocardiographic features suggest that the recipient is also exposed to RAS components. In this study we investigated the role and origin of RAS components in the recipient fetus. Monochorionic diamniotic (MCDA) pregnancies were recruited from a tertiary fetal medicine service. Cord blood was collected from MCDA twins (TTTS and control non-TTTS) at delivery for renin and angiotensin II immunoassays. Placental tissue was flash-frozen for mRNA and protein expression or formalin-fixed for immunohistochemistry. Archival placenta and kidney samples were used for immunohistochemistry and in-situ hybridization. Plasma renin levels were elevated (p<0.05) in recipients (median 201pg/ml, range 54-315pg/ml) and donors (125pg/ml, 25-296) with TTTS compared to controls (2.5pg/ml, 1.1-1.5pg/ml). The same was found with angiotensin II with high levels in both recipients (300.5pg/ml, 86.1-488pg/ml) and donors (239pg/ml, 76.6-422) compared to controls (169.5pg/ml, 89-220pg/ml, p<0.05). Renin mRNA expression, and protein appeared qualitatively higher in the placental territory of the recipient compared to that of the donor and non-TTTS controls. We conclude that both fetuses in TTTS are exposed to high levels of RAS components; these appear to be produced from different sites, namely the kidney of the donor, and the placenta of the recipient. Given the markedly different phenotypes in the genetically identical fetuses with TTTS, we suggest that the source of RAS components may influence their clinical manifestations.  相似文献   
24.

Objective

To assess trends in twinning over four decades using a population-based registry.

Design

Ecological study to conduct trend analysis of twin pregnancies in a geographically defined area over 40 years.

Setting

All pregnancies in the Cardiff and Vale of Glamorgan area of South Wales from 1965 to 2004, as recorded in the Cardiff Birth Survey (CBS) database.

Methods

Trends of the incidence of all twin pregnancies (≥18 weeks of gestation) were calculated in 5-year increments, beginning with 1965–1969 and ending in 2000–2004. Natural twinning rates could only be calculated for the terminal five time periods (i.e., 1980–1984, 1985–1989, 1990–1994, 1995–1999, and 2000–2004), when information regarding non-spontaneous (iatrogenic) twinning was first collected in the database. All results were adjusted for maternal age.

Results

The total twinning rate was 13.1 per 1000 pregnancies in the 1st time period (1965–1969). Subsequently, there was a gradual reduction in twinning, reaching a nadir of 10.3 per 1000 for the time period 1980–1985 (Z = 3.15, P value < 0.001). This was followed by a gradual increase in twinning, reaching a maximum of 15.7 per 1000 for both 1995–1999 and 2000–2004 (Z = −5.18, P value < 0.0001). After exclusion of the cases of iatrogenic pregnancies, the natural twinning rate showed a continuous and gradual increase from 10 per 1000 spontaneous pregnancies in 1980–1984 to 13.3 per 1000 in 2000–2004 (Z = −5.08, P value < 0.0001).

Conclusion

The data showed a gradual, continuous increase in natural twinning rates over the last two decades. Such an increase cannot be attributed to the rise in maternal age alone.  相似文献   
25.
26.
目的 报道连头婴分离手术中有关静脉窦处理及重建方法与临床效果。方法 采用显微手术分离连头婴共用的矢状窦,窦汇,横窦及直窦,用转流管分别作右婴的矢状窦,直窦与颈内静脉转流术,以及应用人造血管移植进行重建,在手术中确保左婴有完整的矢状窦,窦汇及横窦。结果 左婴术后功能恢复正常,右婴术后22h死于肾衰竭,高钾血症。结论 应用显微外科手术进行静脉窦转流和重建是连头婴分离手术成功的关键技术之一。  相似文献   
27.
28.
We describe the anaesthetic management for magnetic resonance image scanning, angiography and surgical operations in three sets of conjoined twins (ischiopagus, throracopagus and pygopagus) in King Chulalongkorn Memorial Hospital during 1996-2002. The anaesthetic technique and associated problems are summarized.  相似文献   
29.
Transmesenteric hernia is a rare cause of intestinal obstruction most commonly affecting the small bowel. The mesenteric defect is usually 2 to 3 cm in diameter. The authors describe 2 cases of young pediatric patients presenting with bowel obstruction resulting from a congenital mesenteric defect. The initial patient had a 30-cm-wide congenital defect in the ileal mesentery through which the sigmoid colon and some loops of small bowel had herniated. The second patient is a newborn infant who presented with symptoms and radiographic evidence of proximal bowel obstruction initially thought to be resulting from malrotation with midgut volvulus but was found at surgical exploration to have a small defect in the ileal mesentery.  相似文献   
30.
Freiberg's infraction is an ostechondrosis of a lesser metatarsal head resulting in degeneration of the metatarsophalangeal joint. Several mechanisms have been suggested in its pathenogenesis. Freiberg first described the entity and believed single impact trauma was the underlying cause. Repetitive biomechanical microtrauma is the most widely accepted etiologic theory. Other factors contributing to its development include aseptic necrosis, ischemia, and a congenital predisposition. We present a case report of Freiberg's infraction occurring in identical twins involving multiple metatarsals in various stages of degeneration. One of the twins was affected unilaterally whereas the other twin was affected bilaterally. Both twins had involvement of the second metatarsal on the same side extremity. The occurrence of Freiberg's infraction in identical twins suggests that an underlying congenital predisposition to the condition may play more of a role than previously considered.  相似文献   
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