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A male infant born prematurely at 31 weeks of gestation weighed 789 g and had mildly brown-colored oral/tracheal aspirates at delivery. The amniotic fluid was also discolored, and its index was below 5. The patient died of hypoxemic respiratory and cardiac failure 2 hours after birth. The maternal profiles showed placenta previa and intrauterine growth restriction (IUGR) at 22 weeks of gestation, and revealed recurrent episodes of antenatal and substantial vaginal bleeding and oligohydramnios, indicating chronic abruption-oligohydramnios sequence. The thickened placenta, weighing 275 g, grossly displayed unevenness and diffuse opacity with green to brown discoloration in the chorioamniotic surface, and revealed chronic massive subchorial hematomas (Breus' mole) with old peripheral blood clot, circumvallation, and infarction. Microscopically, diffuse Berlin-blue staining-positive hemosiderin deposits were readily encountered in the chorioamniotic layers of the chorionic plate, consistent with diffuse chorioamniotic hemosiderosis (DCH) due to Breus' mole, accompanied by diffuse amniotic necrosis. At autopsy, an external examination showed several surface anomalies and marked pulmonary hypoplasia, 0.006 (less 0.012) of lung:body weight ratio. Since Breus' mole has a close relationship with intrauterine hemorrhage, resulting in DCH, IUGR, and/or pulmonary hypoplasia of the newborn, the present features might be typical.  相似文献   
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A member of the tumor necrosis factor receptor superfamily (TNFRSF), TROY/TNFRSF19/TAJ, is highly expressed in the brain of adult mice. Northern blot analysis using mRNA taken from regions of the adult CNS showed the expression of TROY in all regions examined, including the olfactory bulb, cerebral cortex, striatum, and hippocampus. In situ hybridization and immunohistochemistry revealed that TROY mRNA and protein were strongly expressed in the rostral migratory stream (RMS) and subventricular zone (SVZ) of adult mice. In the adult SVZ, some glial fibrillary acidic protein (GFAP)-positive cells (type B cells) are thought to be multipotent neural stem cells. These type B cells divide slowly and generate epidermal growth factor receptor (EGFR)-positive transit-amplifying precursor cells (type C cells) in the presence of epidermal growth factor (EGF). Type C cells give rise to neuron-specific class III beta-tubulin (TuJ1)-positive neuroblasts (type A cells) that migrate to the olfactory bulb along the RMS. TROY-expressing cells were GFAP-positive, EGFR-positive, and TuJ1-negative in the adult SVZ. From these findings, TROY appears to be expressed in type B and type C cells, but not in type A cells, which was supported by immunoelectron microscopy. In addition, TROY was expressed in GFAP-positive astrocytes of the various regions, such as the cerebral cortex, striatum, and hippocampus. Thus, TROY was expressed in uncommitted precursor cells and astroglial lineage cells, suggesting that TROY plays some roles in the regulation of gliogenesis in the adult CNS.  相似文献   
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Spontaneous regression of cancer is a well-known but rare phenomenon, and it is extremely rare for sarcomas. The current case is an 85-year-old woman with a multinodular lesion diagnosed as myxofibrosarcoma in the scapular region. The maximum size of the tumor at the initial visit was 10 cm, and it decreased to less than 2 cm without any treatment. After a period of regression of about 6 months, the tumor began to grow, and resection was performed. No prior case of spontaneous regression has been reported in myxofibrosarcoma or other primary sarcomas. Interestingly, the regression took place after the occurrence of pneumonia, suggesting a possible relationship.  相似文献   
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Objectives To assess the usefulness of free-angle M-mode echocardiography in measuring left ventricular (LV) dimension and global systolic function. Background The validity of conventional M-mode echocardiography in assessing LV dimension and global systolic function is well known; the incidental angle between the M-mode cursor and true LV minor axis diameter, however is a potential cause of measurement error. Free-angle M-mode echocardiography may overcome the limitation of M-mode cursor arrangement in conventional M-mode echocardiography. Methods Thirteen normal volunteers and 10 patients in whom abnormal left ventricular wall motion was not detected by echocardiography (mean age, 53±17 years) were enrolled in this study. Conventional and free-angle M-mode echocardiographic images of the LV were obtained by echocardiography (ALOKA SSD-5500) using a 2.5-MHz transducer, and the LV end-diastolic (LVDd) and end-systolic (LVDs) dimensions were measured by the leading edge method. LV end-diastolic and end-systolic volumes were calculated using a formula by Teichholz, and the LV ejection fraction (LVEF) was obtained. Data from conventional M-mode echocardiography and free-angle M-mode echocardiography were then compared. Results Measurements obtained with conventional M-mode and free-angle M-mode echocaardiography were strongly correlated. Correlation coefficients for LVDd, LVDs, and LVEF were 0.98, 0.98, and 0.96, respectively (p<0.001 in each case). Conclusions Assessment of left ventricular dimension, and global systolic function with free-angle M-mode can be as accurate as conventional M-mode in subjects in whom left ventricular wall motion abnormality is not detectable by echocardiogram. Moreover, when there is improper M-mode cursor direction in conventional echocardiography, free-angle M-mode echocardiography can assess global left ventricular systolic function more accurately and conveniently than conventional M-mode echocardiography.  相似文献   
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目的 探讨用逆转录 聚合酶链反应 (RT PCR)技术检测滑膜肉瘤石蜡包埋组织中SYT SSX融合基因的可行性。方法 我们采用RT PCR方法对 37例福尔马林固定、石蜡包埋的滑膜肉瘤组织中SYT SSX融合基因转录本进行了检测。为探讨SYT SSX融合基因对滑膜肉瘤的特异性 ,一系列非滑膜肉瘤的肿瘤标本作为阴性对照。融合基因检测结果用测序的方法进行了证实。结果  37例滑膜肉瘤中 33例 (89 2 % )可检测出SYT SSX融合基因。 34例非滑膜肉瘤的肿瘤标本中均未显示SYT SSX融合基因产物扩增信号。此 34例标本中均可检测到PBGDmRNA表达。 33例SYT SSX阳性滑膜肉瘤中 ,SYT SSX1阳性 2 2例 ,SYT SSX2阳性 6例 ,其余 5例无法区分融合基因类型。融合基因类型与组织学亚型间存在相关性。所有 10例双相型滑膜肉瘤均为SYT SSX1型 ,而所有SYT SSX2阳性滑膜肉瘤均为单相型 (P <0 0 5 )。结论 我们的结果提示 ,RT PCR技术可以用于存档的福尔马林固定、石蜡包埋组织 ,作为滑膜肉瘤诊断和鉴别诊断敏感而且可靠的技术。SYT SSX融合基因类型与组织学亚型间存在相关性。SYT SSX2型仅见于单相型滑膜肉瘤。  相似文献   
39.
This investigation was designed to determine if liver diseases can modify the pharmacodynamics of the central nervous system depressants phenobarbital and ethanol. Two experimental models of liver diseases in rats were used: extrahepatic cholestasis produced by bile duct ligation and hepatic necrosis induced by carbon tetrachloride administration. Phenobarbital (both models) or ethanol (cholestasis model only) was infused slowly intravenously until the rats lost their righting reflex. Drug concentrations in serum, brain, and cerebrospinal fluid at that time were determined in the diseased animals as well as in sham-operated or solvent-treated controls. Phenobarbital concentrations at the onset of action were not significantly different between controls and either 5-d or 12-d cholestatic rats, except for total serum concentrations which were lower in the cholestatic groups due to reduced protein binding. Ethanol concentrations were slightly but statistically significantly lower in 12-d cholestatic rats as compared with controls. Neither 5-d nor 12-d carbon tetrachloride-induced hepatic dysfunction had any significant effect on phenobarbital concentrations at the onset of loss of righting reflex, except for a marginal decrease in the cerebrospinal fluid concentration of rats that had been treated for 5 d with the hepatotoxin. It was concluded that, under the experimental conditions, the hepatic diseases investigated did not have appreciable effects on the central nervous system response to the hypnotic action of phenobarbital and ethanol.  相似文献   
40.
Histological abnormalities of the brain in autism have been investigated extensively. We studied metabolites in the hippocampus-amygdala (HA) region and cerebellum. We examined the right HA region and left cerebellar hemisphere of 27 autistic patients 2–18 years old, 21 boys and 6 girls and 10 normal children 6–14 years old, 4 boys and 6 girls, using the STEAM sequence. This sequence was used to minimise the influence of relaxation times. The N-acetyl aspartate (NAA) concentration was significantly lower (P = 0.042) in autistic patients than in normal children (9.37 and 10.95 mM, respectively). There was no significant difference in other metabolites. The correlation coefficient (r value) of NAA between the HA region and cerebellum was 0.616. The decreased NAA concentration may be due to neuronal hypofunction or immature neurons. The NAA concentration in the HA region and cerebellum may be related, because of neuronal circuits or networks. Received: 5 December 1998 Accepted: 16 December 1998  相似文献   
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