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121.
122.
Dr. David A. Danford Bruce M. McManus Stephen M. Nielsen Michael G. Levine Howard W. Needelman 《Pediatric cardiology》1993,14(4):242-246
Summary Correlative echocardiographic and pathological findings in a thoracopagus with conjoined hearts are reported. One twin had tricuspid atresia with discordant atrioventricular connections and concordant ventriculoarterial connections. The morphologic right ventricle was hypoplastic and there was a large muscular ventricular septal defect. The other twin had hypoplasia of the mitral valve anulus and left ventricle with double-outlet right ventricle and pulmonary valve atresia. The tricuspid valve was severely insufficient in part because of a large orifice and redundant, elongated leaflets with abnormal chordal attachments. The left ventricles of these two twins shared a perforated common free wall with at least two large defects allowing mixing of the circulations at that level. Not all anatomic details were established conclusively by fetal echocardiography; however, sufficient diagnostic information was obtained to support a decision not to aggressively resuscitate these twins after elective cesarean delivery at 31 weeks' gestation. 相似文献
123.
J. J. Martin J. G. Leroy C. Ceuterick J. Libert P. Dodinval L. Martin 《Acta neuropathologica》1981,53(2):87-91
Summary Two new cases of Krabbe disease were diagnosed prenatally in a family with two previous affected children. The activity of galactosylceramide--galactosidase was virtually absent in cultured amniotic cells.The prenatal diagnosis was confirmed enzymatically in cultured fibroblasts, brain, and visceral organs.Light and electron microscopy studies in both fetuses, 20 and 23 weeks of gestational age respectively, revealed the presence of typical globoid cells in the white matter of the spinal cord. Specific inclusions were also found in the brain stem and in peripheral nerves of the second fetus.A comparison with other Krabbe disease fetuses described in the literature contributes to the consensus that abnormal morphological findings can be expected in particular in the most actively myelinating areas of the nervous system.Although most of the cells containing the specific melusions are probably non-glial in nature, some of them could represent myelination glia.This work was supported by the FGWO (grants nos. 3.0033.77 and 3.0012.77), by the FRSM (grant no. 3.4542.79), and by the Baron Charles Bracht Foundation 相似文献
124.
Hilary A. Perr John R. Grider A. Scott Mills Michael Kornstein David A. Turner Robert F. Diegelmann Martin F. Graham 《Anatomy and embryology》1992,185(6):517-527
Summary The extracellular matrix influences organogenesis by modulating cell behavior. In humans, collagen is the major matrix constituent of the adult intestinal wall and is synthesized by smooth muscle cells. The objective of the current study was to examine collagen production by fetal human intestinal smooth muscle cells isolated during intestinal morphogenesis. Techniques were developed for the isolation and culture of human fetal intestinal smooth muscle cells. The cultured cells were confirmed as muscle by immunohistochemical stains for cytoskeletal filaments and documentation of contractile behavior. In culture, these cells stained for mesenchymal and muscle cytoskeletal proteins: vimentin, actin, and desmin, and did not stain for neural or epithelial markers. The muscle cells contracted in response to acetylcholine, in contrast to human fetal dermal fibroblasts which did not contract appreciably. Collagen production was assayed by the uptake of [3H]-proline into collagenase-digestible protein. Collagen production was greatest at 11 weeks gestation, the youngest age studied. By 20 weeks gestation, collagen production had decreased to adult levels. However, when compared to another matrix-producing fetal mesenchymal cell, the dermal fibroblast, intestinal smooth muscle cells produced twice as much collagen. Collagen types were determined by polyacrylamide slab gel electrophoresis. Smooth muscle cells predominantly produced types I and III collagen chains. Therefore, collagen production is a significant function of human fetal intestinal smooth muscle cells, and probably plays a major role in the development of intestinal structure. The in vitro model presented here provides a means of studying the regulation of this collagen production throughout intestinal organogenesis. 相似文献
125.
Serum α1-microglobulin and β2-microglobulin for the estimation of fetal glomerular renal function 总被引:1,自引:0,他引:1
As proteins cannot cross the placenta levels of the microproteins 1-microglobulin (1MG) and 2-microglobulin (2MG) can be used to assess fetal glomerular renal function. 1MG, 2MG and creatinine were routinely determined in cord and maternal blood of 133 newborns [gestational age (GA) 25–42 weeks]. Twenty-nine patients with suspected impaired maternal or fetal renal function were studied separately and two fetuses were studied in utero. The mean fetal 2MG concentration fell from 3.87±0.56 mg/l in the 25–31 weeks GA group to 2.60±0.50 mg/l in the mature newborn group. 1MG concentration fell from 3.10±0.51 to 2.25±0.49 mg/dl. In contrast, the mean maternal 1MG concentration rose from 1.73±0.69 mg/l in the 25–31 weeks GA group to a mean of 1.83±0.48 mg/l in the mature newborn group; 1MG rose from 3.96±0.58 to 4.33±1.6 mg/dl. Maternal and fetal creatinine levels were identical. Fetal microprotein levels fall during intra-uterine development as glomerular filtration rate (GFR) rises. There is no correlation between cord blood and maternal 1MG or 2MG concentrations. In 13 children with urological anomalies only 1 had elevated microprotein levels and he later developed renal insufficiency. Determination of microprotein levels in fetal serum can be used to detect severe renal function disturbances and to estimate GFR independently of maternal renal function. 相似文献
126.
Fetal intracranial pathology detected in the early second trimester during 1237 transvaginal sonographic scans is presented. In a sharp contrast to simple choroid cysts, which disappear at the end of the second trimester as part of a benign course, gross distortion of the choroid plexus was found to be related to the later diagnosis of hydrocephalus. Three patterns of this abnormality are early absence of the plexus, hypoplasia and shrinkage, and "Swiss cheese" appearance. Ventriculomegaly in hydropic fetuses does not distort the normal architecture of the choroid plexus. Certain abnormal features of the choroid plexus, observed as early as the 14th week, menstrual age, are landmarks of developing hydrocephalus, currently detectable only later in pregnancy. 相似文献
127.
Connective tissue growth factor: a novel player in tissue reorganization after brain injury? 总被引:5,自引:0,他引:5
Recent studies have suggested a role of connective tissue growth factor (CTGF) in repair processes of the skin as well as in various types of fibrotic disease. However, a function of this molecule in central nervous system (CNS) repair has not been demonstrated yet. In this study we analysed the temporal and spatial expression pattern of CTGF after unilateral kainic acid lesions of the hippocampal CA3 region in mice. We found a strong induction of CTGF mRNA and protein expression in neurons and glial cells of the lesioned hippocampus. Interestingly, increased expression of this mitogen was accompanied by elevated levels of the extracellular matrix molecule fibronectin, which is a known target of CTGF action. Therefore, our data indicate a novel function of CTGF in postlesional restructuring of the hippocampus, where it possibly participates in glial scar formation. 相似文献
128.
129.
母血中胎儿有核红细胞数量与胎儿异常的关系 总被引:7,自引:0,他引:7
目的 :探讨母血中胎儿有核红细胞数量与胎儿异常的关系 ,为将它用于无创性产前诊断提供实验依据。方法 :对孕 6~ 40周的 86例妇女 (包括胎儿正常组 68例、胎儿异常组 1 8例 )的外周血进行单密度梯度离心、瑞氏染色和细胞计数 ,分析母血中胎儿有核红细胞数量与孕周、胎儿异常及胎儿性别的关系。结果 :胎儿正常组 ,母血中胎儿有核红细胞平均数量为 1 4.2 3±1 2 .0 1 /ml,与妊娠周数呈直线相关 (R >R0 .0 5)。胎儿异常组中 ,母血中胎儿有核红细胞平均数量较正常胎儿组显著增加 ,约为 3 8.73± 2 4.97/ml,且与妊娠周数无明显直线相关性。母体外周血中胎儿有核红细胞数量与胎儿性别无统计学相关性。结论 :胎儿发生异常时母血中胎儿有核红细胞数量较正常妊娠时增加。母血中胎儿有核红细胞数量在胎儿正常时随孕周而增加 ,且不受胎儿性别的影响。母血中胎儿有核红细胞计数可以辅助用于产前筛查胎儿异常的发生。 相似文献
130.
白细胞介素2激活脐血单个核细胞体外抗肿瘤活性的实验研究 总被引:10,自引:0,他引:10
为探讨白细胞介素2(IL-2)激活脐血单个核细胞(ACB)对白血病细胞株HL-60和K562细胞的杀伤作用以及脐血被激活后能否保持其造血祖细胞生成活性(PCA),采用3H-胸腺嘧啶核苷前标记释放法和半固体培养等方法对其进行了研究。结果:IL-2激活的脐血细胞具有明显的抗肿瘤活性,且不影响其PCA。IL-2激活脐血细胞的最适条件为:(1)细胞浓度为1×106ml;(2)IL-2浓度为1000U/ml;(3)效靶比为1001;(4)体外培养72小时。脐血经IL-2激活后免疫表型发生明显变化,产生肿瘤坏死因子(TNFα)及白细胞介素6(IL-6),且生成大颗粒淋巴细胞(LGL)。LGL与K562细胞作用后,后者呈凋亡特征。研究结果为临床应用ACB治疗白血病提供了实验依据。 相似文献