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81.
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
82.
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
83.
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
84.
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
85.
86.
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
87.
M. Respondek A. Włoch P. Kaczmarek D. Borowski J. Wilczynski E. Helwich 《Pediatric cardiology》1997,18(5):361-366
Fifty fetuses referred to the Polish Mother's Memorial Hospital for fetal echocardiography between January 1, 1991 and June
1, 1995 were evaluated. The mean fetal gestational age at the time of diagnosis of arrhythmia was 34.1 weeks, and the mean
gestational age at the time of delivery was 38.7 weeks. Checkup echocardiographic examinations were performed every 10–14
days, for a mean 2.4 studies per fetus. In most cases (48/50, 96%), premature atrial contractions were present during the
first echocardiography examination. The fetal heart study was normal in 30 cases; in 7 (14%) there was tricuspid valve regurgitation,
in 7 (14%) an atrial septal aneurysm, in 4 congenital heart defects, in 1 myocardial hypertrophy, and in 1 disproportion in
the four-chamber view. Of the 50 fetuses, 43 underwent regular echocardiographic monitoring alone; in 7 cases, based on the
presence of additional echocardiographic findings, pharmacotherapy was applied (digoxin, verapamil, or both). Three neonates
died after delivery owing to malformations in two cases (one critical aortic stenosis, one spina bifida plus hygroma colli)
and due to myocarditis in one case. In six of seven newborns treated in utero, myocarditis was diagnosed after birth (including
the one with neonatal demise). Most of the newborns were in good condition after birth, their mean Apgar score being 8.6 and
the mean birth weight 3259 g. We concluded that most extrasystoles represent an isolated anomaly, not affecting the fetal
condition. Their presence should not influence the obstetric care and may require only echocardiographic monitoring. In most
of our cases the premature contractions subsided after birth, although sometimes they preceded fetal supraventricular tachycardia
or appeared after congenital myocarditis. 相似文献
88.
David Marden DO Robert S. McDuffie Jr. MD Richard Allen MD Dena Abitz RNC BSN 《American journal of obstetrics and gynecology》1997,176(6):1386-1388
OBJECTIVES: Our purpose was to determine (1) whether a fetal acoustic stimulation test results in more palpable fetal movement compared with a mock test (control) and (2) whether palpated fetal movements after a fetal acoustic stimulation test are accompanied by a reactive nonstress test.STUDY DESIGN: In a randomized controlled trial we studied women seen in the labor and delivery suite for various indications. Women were excluded for multiple gestation, <31 weeks' gestational age, treatment with magnesium sulfate or narcotics, or ruptured membranes. Informed consent was obtained from eligible women, who were then randomized to a test or control group. We placed an acoustic stimulator on the abdomen of each woman, but only the test group was stimulated. We assessed fetal movement by a grading system: 0 = no fetal movement felt by patient or tester, 1 = fetal movement felt by patient only, 2 = fetal movement felt by tester, 3 = visual movement seen by tester. A positive fetal acoustic stimulation test result was defined as one with any fetal movement felt or seen by the tester (grades 2 or 3). We then performed a nonstress test. We compared rates of a positive fetal acoustic stimulation test in the test and control groups with the χ2 test. A p value <0.05 was considered significant.RESULTS: We randomized 297 women to the test group and 280 women to the control (mock test) group. Of women tested with the fetal acoustic stimulation test, 81% had fetal movement by palpation or visualization (grades 2 or 3) compared with 19% of the control group (p < 0.0001, odds ratio 19.29, 95% confidence interval 12.42 to 30.07). Of the test group, 283 (95%) had a reactive nonstress test and 14 (5%) had nonreactive tests; the control group had 267 (95%) reactive and 13 (5%) nonreactive nonstress tests. Of 242 patients in the test group with a positive fetal acoustic stimulation test, 236 (98%) had a reactive nonstress test. Of those in the test group with fewer than three contractions per 10 minutes, 164 (89%) had a positive fetal acoustic stimulation test. Of these, 162 (99%) had a reactive nonstress test.CONCLUSION: The fetal acoustic stimulation test evokes significantly more palpated or visualized fetal movement than in controls. Palpated or visualized fetal movement after acoustic stimulation was almost always accompanied by a reactive nonstress test. (Am J Obstet Gynecol 1997;176:1386-8.) 相似文献
89.
肿瘤坏死因子在妊高征发病中的作用 总被引:3,自引:0,他引:3
目的:探讨肿瘤坏死因子(TNF)在妊高征发病中的作用及其对胎儿生长的影响。方法:应用放射免疫法对正常晚期妊娠妇女16例(对照组)及妊高征患者46例(妊高征组)的血浆、羊水和新生儿脐血中TNF进行检测。结果:分娩前妊高征组血浆TNF水平较对照组高,以中、重度妊高征者增高显著(P<0.05);产后72小时妊高征组血浆TNF水平下降,与对照组差异无显著性。对照组及轻度妊高征者新生儿脐血TNF水平与母血接近,羊水TNF水平明显低于母血(P<0.05);中、重度妊高征者脐血和羊水TNF水平均较母血低(P<0.05;P<0.01)。新生儿脐血、羊水中TNF水平在两组间差异无显著性。在中、重度妊高征者中,合并胎儿生长迟缓者其羊水和新生儿脐血TNF水平明显高于未合并胎儿生长迟缓者。结论:TNF可能作为母体对胎儿抗原的异常免疫反应的重要介质,在妊高征的发病中起一定作用。 相似文献
90.
妊高征患者的胎儿血流速度波形改变特点研究 总被引:1,自引:0,他引:1
目的:研究妊高征患者的胎儿脐动脉、肾动脉以及大脑中动脉的血流速度波形的变化特点。方法:妊高征患者96例,正常妊娠148例,于产前1周内行彩色多普勒超声检测胎儿脐动脉、肾动脉和大脑中动脉的搏动指数(PI),产后随访新生儿预后。结果:随着妊高征的加剧,胎儿脐动脉和肾动脉的PI上升,大脑中动脉的PI则改变不明显。在围产儿预后良好和不良的两组中,随着妊高征的加重,胎儿脐动脉、肾动脉和大脑中动脉的PI均有上升的趋势,但预后不良组的改变比对照组明显。按正常妊娠和轻度、中度、重度妊高征分成4组,胎儿窘迫者脐动脉和肾动脉的PI上升,大脑中动脉的PI下降。结论:妊高征和胎儿窘迫对胎儿脐动脉和肾动脉的血流波形改变有协同作用,对大脑中动脉的改变有阻抗作用 相似文献