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71.
Charles D. Laughlin 《Human nature (Hawthorne, N.Y.)》1991,2(3):171-213
Ample evidence from various quarters indicates that the perceptual-cognitive competence of the pre- and perinatal human being
is significantly greater than was once thought. Some of the evidence of this emerging picture of early competence is reviewed,
and its importance both as evidence of the biogenetic structural concept of “neurognosis” and for a theory of enculturation
is discussed. The literature of pre- and perinatal psychology, especially that of developmental neuropsychology, psychobiology,
and social psychophysiology, is incorporated, and some of the implications of these data for a theory of enculturation are
suggested.
This paper was presented at the annual meeting of the American Anthropological Association, Washington, D.C., November 1989.
Charles D. Laughlin, Professor of Anthropology at Carleton University, Ottawa, Canada, has done ethnographic fieldwork among
the So of northeastern Uganda and among Tibetan lamas in Nepal and India. He completed postdoctoral studies in neurophysiology
at the Institute of Neurological Sciences, University of Pennsylvania. He is editor of both theNeuroanthropology Network Newsletter and thePre- and Peri-Natal Psychology Journal. 相似文献
72.
PurposeFetal biometric measurements face a number of challenges, including the presence of speckle, limited soft-tissue contrast and difficulties in the presence of low amniotic fluid. This work proposes a convolutional neural network for automatic segmentation and measurement of fetal biometric parameters, including biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL) from ultrasound images that relies on the attention gates incorporated into the multi-feature pyramid Unet (MFP-Unet) network.MethodsThe proposed approach, referred to as Attention MFP-Unet, learns to extract/detect salient regions automatically to be treated as the object of interest via the attention gates. After determining the type of anatomical structure in the image using a convolutional neural network, Niblack's thresholding technique was applied as pre-processing algorithm for head and abdomen identification, whereas a novel algorithm was used for femur extraction. A publicly-available dataset (HC18 grand-challenge) and clinical data of 1334 subjects were utilized for training and evaluation of the Attention MFP-Unet algorithm.ResultsDice similarity coefficient (DSC), hausdorff distance (HD), percentage of good contours, the conformity coefficient, and average perpendicular distance (APD) were employed for quantitative evaluation of fetal anatomy segmentation. In addition, correlation analysis, good contours, and conformity were employed to evaluate the accuracy of the biometry predictions. Attention MFP-Unet achieved 0.98, 1.14 mm, 100%, 0.95, and 0.2 mm for DSC, HD, good contours, conformity, and APD, respectively.ConclusionsQuantitative evaluation demonstrated the superior performance of the Attention MFP-Unet compared to state-of-the-art approaches commonly employed for automatic measurement of fetal biometric parameters. 相似文献
73.
Maria Teresa de los Frailes Lucinda Cacicedo Maria Jesús Lorenzo Franco Sánchez-Franco 《Journal of neurochemistry》1989,52(5):1333-1339
The influence of membrane depolarization on somatostatin secretion and protein synthesis by fetal and neonatal cerebrocortical neurons was studied. Cortical cells obtained by mechanical dispersion were maintained as monolayer cultures for 8 days. The ability of fetal cerebrocortical and hypothalamic cells to release immunoreactive somatostatin (IR-SRIF) was confirmed. Total protein synthesis was determined by the incorporation of [3H]phenylalanine into trichloroacetic acid-precipitable proteins. To study the effect of acute depolarization on protein synthesis, cells were incubated for 30 min with [3H]phenylalanine or [3H]leucine and the depolarizing agent. In fetal cerebrocortical cells, potassium (30 and 56 mM) decreased protein synthesis and RNA levels and increased IR-SRIF release. Depolarization by veratridine, a sodium channel activator, induced a similar effect. The effect of veratridine on IR-SRIF and protein synthesis was reversed by tetrodotoxin, a sodium channel blocker, or verapamil, a calcium channel blocker. These findings suggest that protein synthesis by cerebrocortical cells is decreased in fetal brain cells by membrane depolarization and is dependent on Na+ and Ca2+ entry into cells. In postnatal (day 7) cerebrocortical cells, depolarization induced by high potassium concentrations led to a concomitant increase in protein synthesis, RNA content, and somatostatin release. These findings indicate that depolarization of the cellular membrane is coupled to an increase in protein synthesis in neonatal, but not in fetal, dispersed brain cells. 相似文献
74.
John R. Shainoff 《Biochemical and biophysical research communications》1980,95(2):690-695
A gel matrix that can be used in sequence to separate proteins and then immobilize them was obtained by incorporating into agarose an aldehydic ligand with readily controllable reactivity. The gel was prepared by etherifying agarose with glycidol and subsequently oxidizing with periodate. It provided an inert matrix equivalent to ordinary agarose for separating proteins at neutral or acidic pH, but rapidly absorbed them through formation of stable alkyl amine linkages on exposure to either alkaline or concentrated NaCNBH3. Thus, the protein could be fixed without use of denaturants. The ability to array proteins electrophoretically on an immobilizing substrate opens new possibilities for analysis of complex mixtures by providing means for carrying out affinity binding assays in relation to physical properties of the protein, and for performing multiple tests of composition without loss or spread. 相似文献
75.
Silencing of SOCS‐1 and SOCS‐3 suppresses renal interstitial fibrosis by alleviating renal tubular damage in a rat model of hydronephrosis 下载免费PDF全文
76.
The causes of recurrent spontaneous abortion (RSA) and fetal malformations are multifactorial and unclear in most cases. Environmental, maternal, and genetic factors have been shown to contribute to these defects. Whole-exome sequencing (WES) is widely used to detect genetic variations associated with human diseases and has recently been successfully applied to unveil genetic causes of unexplained recurrent spontaneous abortion (URSA) and fetal malformations. Here, we review the current discovery and diagnosis strategies to identify the underlying pathogenic mutations of URSA and fetal malformations using WES technology and propose to further develop WES, both to advance our understanding of these diseases and to eventually lead to targeted therapies for reproductive disorders. 相似文献
77.
目的:通过优化现有的蛋白芯片检测过程,在保证检测准确性的同时缩短甲胎蛋白(Alpha Fetal protein,AFP)的检测时间,提高检测效率,为原发性肝癌的筛查提供经济、便捷、省时、有效的检测方法。方法:本研究在传统蛋白芯片检测流程(1-1.5小时)的基础上,通过优化检测流程将检测时间缩短至18分钟,并且通过和传统方法进行比较,评价该优化方法的检测效能。结果:与传统蛋白芯片检测方法相比,本优化方法的检测时间缩短至18分钟。重复检测同一样本,传统方法 AFP水平为16.50±1.172ng/m L,优化方法 AFP水平为18.33±1.029 ng/m L,结果无明显统计学差异(P=0.251)。结论:本研究成功地优化了AFP的蛋白芯片检测流程,在缩短检测时间的同时,保证了检测的准确率,是一种经济省时易操作的AFP检测方法。 相似文献
78.
Trypanosoma lewisi has previously been described as a nonpathogenic parasite of the rat, but these experiments demonstrate that both embryonal and maternal death may occur in the pregnant rat after infection with this parasite.Rats infected early in the first week of pregnancy resorbed their young with little apparent difficulty, and exhibited parasitemia curves typical of nonpregnant infected females of similar age.Rats infected late in the first week of pregnancy experienced greater difficulty resorbing the young, with half of the females dying shortly before parturition. The parasitemia counts were also similar to those of nonpregnant infected rats.The majority of rats infected during the midterm of pregnancy died at the time of parturition, without giving birth to their young. The number of parasites in these animals was abnormally high compared to nonpregnant infected females. Unusually large numbers of dividing trypanosomes were present in the placentae of these animals, many of them containing 8–16 nuclei and kinetoplasts.Animals infected during the last week of pregnancy gave birth to litters of normal size with little apparent difficulty, and had extremely low parasite counts.The hematocrits of all groups of infected animals showed a decrease at the time of peak parasitemia, and the hematocrits of all groups of pregnant rats showed a decrease at the time of birth, except for those infected when day 2 pregnant. These animals completely resorbed their young. The weight losses of rats infected on day 2 and day 6 of pregnancy reflected a termination of pregnancy. 相似文献
79.
Manjurul Haque Lisa M. Starr Kristine G. Koski Marilyn E. Scott 《International journal for parasitology》2018,48(1):51-58
Maternal dietary protein deficiency and gastrointestinal nematode infection during early pregnancy have negative impacts on both maternal placental gene expression and fetal growth in the mouse. Here we used next-generation RNA sequencing to test our hypothesis that maternal protein deficiency and/or nematode infection also alter the expression of genes in the developing fetal brain. Outbred pregnant CD1 mice were used in a 2 × 2 design with two levels of dietary protein (24% versus 6%) and two levels of infection (repeated sham versus Heligmosomoides bakeri beginning at gestation day 5). Pregnant dams were euthanized on gestation day 18 to harvest the whole fetal brain. Four fetal brains from each treatment group were analyzed using RNA Hi-Seq sequencing and the differential expression of genes was determined by the edgeR package using NetworkAnalyst. In response to maternal H. bakeri infection, 96 genes (88 up-regulated and eight down-regulated) were differentially expressed in the fetal brain. Differentially expressed genes were involved in metabolic processes, developmental processes and the immune system according to the PANTHER classification system. Among the important biological functions identified, several up-regulated genes have known neurological functions including neuro-development (Gdf15, Ing4), neural differentiation (miRNA let-7), synaptic plasticity (via suppression of NF-κβ), neuro-inflammation (S100A8, S100A9) and glucose metabolism (Tnnt1, Atf3). However, in response to maternal protein deficiency, brain-specific serine protease (Prss22) was the only up-regulated gene and only one gene (Dynlt1 a) responded to the interaction of maternal nematode infection and protein deficiency. In conclusion, maternal exposure to GI nematode infection from day 5 to 18 of pregnancy may influence developmental programming of the fetal brain. 相似文献
80.
Yoo SJ Boylan JM Brautigan DL Gruppuso PA 《Archives of biochemistry and biophysics》2007,461(2):186-193
The prototypical form of the Ser/Thr phosphatase PP2A is a heterotrimeric complex consisting of catalytic subunit (C), and A and B regulatory subunits. C-terminal methylation of PP2A-C influences holoenzyme assembly. Using late gestation development in the rat as an in vivo model of liver growth, we found that PP2A-C protein and activity levels were higher in fetal compared to adult liver extracts. However, unmethylated PP2A-C was much higher in the adult extracts. In MonoQ fractionation, unmethylated C eluted separately from methylated C, which was present predominantly in ABC heterotrimers. Gel filtration chromatography revealed that some unmethylated C was present as free catalytic subunit in adult liver. In addition, a significant proportion of PP2A was in inactive forms that may involve novel regulatory subunits. Our results indicate that methylation of PP2A-C appears to be a primary determinant for the biogenesis of PP2A heterotrimers. 相似文献