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31.
OBJECTIVE: To present prenatal findings and maternal and neonatal outcomes following second- and early third-trimester spontaneous antepartum uterine rupture events in our institute. METHOD: Charts of patients with full-thickness second- or early third-trimester symptomatic uterine ruptures locally treated between 1984 and 2007 were evaluated. RESULTS: There were seven events involving six women, all requiring emergency laparotomy, and cesarean section (CS). During the study period in our institute, there were 120 636 singleton deliveries (> or =22 weeks' gestation), including 5 of our cases, while in 2 cases, the rupture occurred earlier (<22 weeks' gestation). The rupture occurred after > or = 1 previous CSs in five cases. Six events were associated with abnormal placentation: placenta previa (n = 3), placenta percreta (n = 1), or both (n = 2). Other associated events included short, interpregnancy (IP) interval (n = 3) and past uterine rupture (n = 2). Pregnant women at gestational age > or = 22 weeks, who had the combination of placenta previa, and previous CS (n = 3), had a higher chance for spontaneous symptomatic antepartum uterine rupture when compared to women with placenta previa without a previous CS (OR 29.3, 95% CI 1.5-569.3, p = 0.007). There were no maternal deaths. Three of the five viable neonates survived. CONCLUSIONS: Spontaneous symptomatic second- or early third-trimester uterine rupture in nonlaboring women is a very rare, obstetric emergency, which is hard to diagnose. Maternal and neonatal outcomes can be optimized by awareness of risk factors, recognition of clinical signs and symptoms, and availability of ultrasound to assist in establishing diagnosis, and enabling prompt surgical intervention.  相似文献   
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Rare pilocytic astrocytomas (PA) have atypical histologic and clinicoradiologic features that raise the differential diagnosis of glioblastoma. Whether ancillary studies can supplement histopathologic examination in placing these cases accurately on the spectrum of WHO Grade I PA to higher-grade glioma is not always clear, partly because these cases are not common. Here, ten PAs with atypical clinicoradiologic and histologic features and six pediatric glioblastoma multiforme (pGBMs) were analyzed for BRAF V600E, IDH1, IDH2, and TP53 mutations. Ki-67, p53, and p16 protein expression were also examined by immunohistochemistry. BRAF–KIAA1549 fusion status was assessed in the PA subgroup. The rate of BRAFKIAA1549 fusion was high in these PAs (5/7 tumors) including four extracerebellar examples. A single BRAF V600E mutation was identified in the fusion-negative extracerebellar PA of a very young child who succumbed to the disease. TP53 mutations were present only in malignant gliomas, including three pGBMs and one case designated as PA with anaplastic features (with consultation opinion of pGBM). IDH1 and IDH2 were wild type in all cases, consistent with earlier findings that IDH mutations are not typical in high-grade gliomas of patients ≤14 years of age. Immunohistochemical studies showed substantial overlap in Ki-67 labeling indices, an imperfect correlation between p53 labeling and TP53 mutation status, and complete p16 loss in only two pGBMs but in no PAs. These results suggest that (a) BRAFKIAA1549 fusion may be common in PAs with atypical clinicoradiologic and histologic features, including those at extracerebellar sites, (b) BRAF V600E mutation is uncommon in extracerebellar PAs, and (c) TP53 mutation analysis remains a valuable tool in identifying childhood gliomas that will likely behave in a malignant fashion.  相似文献   
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The immune system plays a major role in protecting the host against viral infection. Rapid initial protection is conveyed by innate immune cells, while adaptive immunity (including T lymphocytes) requires several days to develop, yet provides high specificity and long-lasting memory. Invariant natural killer T (iNKT) cells are an unusual subset of T lymphocytes, expressing a semi-invariant T cell receptor together with markers of the innate NK cell lineage. Activated iNKT cells can exert direct cytolysis and can rapidly release a variety of immune-polarizing cytokines, thereby regulating the ensuing adaptive immune response. iNKT cells recognize lipids in the context of the antigen-presenting molecule CD1d. Intriguingly, CD1d-restricted iNKT cells appear to play a critical role in anti-viral defense: increased susceptibility to disseminated viral infections is observed both in patients with iNKT cell deficiency as well as in CD1d- and iNKT cell-deficient mice. Moreover, viruses have recently been found to use sophisticated strategies to withstand iNKT cell-mediated elimination. This review focuses on CD1d-restricted lipid presentation and the strategies viruses deploy to subvert this pathway.  相似文献   
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