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21.
C. W. Pittius F. Ellendorff V. Höllt N. Parvizi 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1987,69(1):208-212
Summary Using solution hybridization analysis and Northern blotting with complementary RNA probes labelled to high specific activity, levels of proenkephalin A and B mRNA were analyzed throughout prenatal development in the hippocampus and striatum of fetal pigs. A differential time course for the appearance of these opioid precursor mRNAs was observed: in hippocampus, both mRNAs increased linearly throughout development with proenkephalin B mRNA increasing faster than proenkephalin A mRNA. In striatum, both mRNAs behaved similarly, increasing to a maximum level around mid-gestation and declining thereafter. The differences might be attributed to differential localization of the two precursor systems in the tissues and might be of functional relevance.Abberviations PENK A, PENK B
Proenkephalin A, B
- mRNA
Messenger Ribonucleic Acid
- cRNA
Complementary RNA 相似文献
22.
Polyovular follicles in the ovary of immature mice exposed prenatally to diethylstilbestrol 总被引:2,自引:0,他引:2
Summary Polyovular follicles (PF) occur in the ovary of 30-day-old offspring of ICR/JCL mice given 4 daily subcutaneous injections of 20–2,000 g diethylstilbestrol (DES)/day from days 15 to 18 of gestation. PF containing 2–9 oocytes per follicle in the prenatally DES-exposed mice are increased 33- to 112-fold as compared to controls. In 5- to 25-day-old offspring of mothers given injections of 2,000 g DES/day, PF are observed 17–65 times more frequent than in controls. 相似文献
23.
为了解先天性肾上腺皮质增生症患者的21-羟化酶CYP21B基因中Ile~(172)→Asn错义突变的发生率,根据放大受阻突变体系(Amplificationrefractorymutationsystem,ARMS)的要求,设计了3种引物:5'd(TTGGGAGACTACTCCCTGCTCT)3'(共同引物)、5'd(AGGTGAGGTAACAGA)3'(正常引物)、5'd(AGGTGAGGTAACAGT)3'(突变引物),在7例患儿中进行了检测,发现具有本突变者3例。对其中一例进行的家系分析,结果提示:这组引物有快速、简便的优点,不需使用同位素就能对具有Ile~(172)→Asn变异的高危家庭成员作产前诊断。 相似文献
24.
The contributions of prenatal and postnatal androgen exposure upon the development of sexual behavior in rats were examined by prenatal treatment of pups with an androgen antagonist (flutamide) and postnatal androgenization or castration. Male and female rats were exposed to the androgen receptor-blocker flutamide (FLU) in utero via prenatal injections to the mother on Days 10 through 22 of gestation. At birth (Day 1) males were castrated. Both males and females were injected with either 100 μg testosterone propionate (TP) or oil on Day 1. In adulthood all gonadectomized animals were tested for the display of feminine sexual behavior (lordosis) in response to a range of estrogen dosages. Prenatal exposure to FLU enhanced lordosis in both sexes when compared to vehicle-treated controls. Postnatal TP treatment decreased lordotic potential as expected. However, in animals given TP postnatally, those receiving prenatal flutamide had higher lordosis quotients than animals receiving vehicle treatment. These data confirm (1) that the development of feminine sexual behavior is inhibited by androgen exposure, (2) that such exposure occurs prenatally, (3) that the potential for feminine behavioral differentiation occurs prenatally as well as postnatally, and (4) that androgen acts perinatally to affect estrogen sensitivity in adulthood. 相似文献
25.
Tan JA George E Tan KL Chow T Tan PC Hassan J Chia P Subramanium R Chandran R Yap SF 《Clinical and experimental medicine》2004,4(3):142-147
Abstract
β-thalassemia is the most-common genetic disorder of hemoglobin synthesis in Malaysia, and about 4.5% of the population are
heterozygous carriers of the disorder. Prenatal diagnosis was performed for 96 couples using the Amplification Refractory
Mutation System and Gap-Polymerase Chain Reaction. We identified 17 β-globin defects-initiation codon for translation (T-G),
-29 (A-G), -28 (A-G), CAP +1 (A-C), CD 8/9 (+G), CD 15 (G-A), CD 17 (A-T), CD 19 (A-G), Hb E (G-A), IVS1-1 (G-T), IVS1-5 (G-C),
CD 41/42 (-CTTT), CD 71–72 (+A), IVS2-654 (CT), poly A(A-G), 100-kb Gγ(Aγδβ)° and 45-kb Filipino deletions. The 192 β-alleles studied comprised Chinese (151 patients), Malay (21), Orang Asli from
East Malaysia (15), Filipino (1), Indian (1), Indonesian Chinese (2), and Thai (1). In the Chinese, 2 β-globin defects at
CD 41/42 and IVS2-654 were responsible for 74% of β-thalassemia. β-mutations at CD 19, IVS1-1 (G-T), IVS1-5, poly A, and hemoglobin
E caused 76% of the hemoglobin disorders in the Malays. The Filipino 45-kb deletion caused 73.3% of bthalassemia in the Orang
Asli. Using genomic sequencing, the rare Chinese β-mutation at CD 43 (G-T) was confirmed in 2 Chinese, and the Mediterranean
mutation IVS1-1 (G-A) was observed in a Malay β-thalassemia carrier. The β-globin mutations confirmed in this prenatal diagnosis
study were heterogenous and 65 (68%) couples showed a different globin defect from each other. The use of specific molecular
protocols has allowed rapid and successful prenatal diagnosis of β-thalassemia in Malaysia. 相似文献
26.
孕早期宫颈分泌物中获取胎儿细胞DNA进行产前诊断的可行性 总被引:2,自引:1,他引:2
目的:探索获取胎儿细胞DNA用于产前基因诊断的可行性,及能否用于预期胎儿性别。方法:收集92例孕早期人工流产妇女宫颈分泌物和绒毛组织,提取宫颈分泌物中DNA,扩增Y染色体特异重复序列DNA。短期培养制备绒毛染色体,分析核型确定流产胎儿性别。结果:92例经绒毛染色体核型分析的人工流产胎儿中,正确预期胎儿性别72例,准确率78%。结论:采集孕早期宫颈分泌物,可获得胎儿滋养层细胞DNA用于产前诊断,其准确性和可靠性有待进一步提高。 相似文献
27.
Summary Lung fragments from 10 human fetuses aged 10 to 14 weeks of gestation were implanted into athymic nude mice. Cytodifferentiation of the transplants was studied by both scanning and transmission electron microscopy.Two weeks after implantation mitotic figures of epithelial and stroma cells were observed. In five week old transplants ciliated as well as endocrine cells were found dispersed among undifferentiated bronchial epithelium. During further experimental period epithelial differentiation in the transplants proceeded. Thus, eight week old implants assumed the morphologic appearance of fetal lungs in the canalicular stage displaying prospective type I and II pneumocytes. In addition stroma cells also differentiated forming mature fibroblasts and myofibroblasts.Our study indicates that human fetal lung tissue transplanted into nude mice not only grow but even differentiate. Xenogeneic transplantation of human fetal cells and tissues, therefore, offers additional opportunities to investigate the prenatal development of human tissues.Supported by EMDO and by Hartmann Müller Foundation 相似文献
28.
产前筛查和基因多态性位点在唐氏综合征产前诊断中的应用 总被引:6,自引:3,他引:6
目的 在建立可靠的产前筛查方法的同时,采用快速,简便,准确的产前诊断方法,防止唐氏综合征(DS)患儿的出生,方法 采用酶联免疫方法测定妊娠14-20w孕妇血清甲胎蛋白(AFP)和绒毛膜促性腺激素β亚基(β-HCG)浓度,结合孕妇年龄,孕周和体重,用计算机软件进行分析,得到每位孕妇所怀胎儿DS风险系数,对筛查出胎儿唐氏综合征高风险孕妇,再利用21号染色体上的6个多态性位点对其作产前基因诊断。结果 经产前筛查,在395例孕妇中发现10例胎儿唐氏综合征高风险孕妇,其中1例产前基因诊断为胎儿唐氏综合征,与染色体核型分析结果相符。结论 产前筛查结合基因多态性在唐氏综合征产前诊断中具有很好的应用价值。 相似文献
29.
K. Iwase M. Takemura T. Shimada S. Wakisaka T. Nokubi Y. Shigenaga 《Anatomy and embryology》1998,197(3):229-247
This study characterizes the developmental expression of NADPH-diaphorase from embryo to adulthood in the forebrain, midbrain
and cerebellum of rat brain via histochemical staining. On embryonic day 12 no neurons stained. Labeling was observed in certain
nuclei from E15 through the postnatal period to adulthood. Labeling in neurons increased or maintained a constant level with
increased age. The embryo demonstrated substantial labeling in neurons of the caudate putamen, bed nucleus of the stria terminalis,
preoptic area, lateral hypothalamic area, paraventricular thalamic nucleus, ventromedial hypothalamic nucleus, magnocellular
nucleus posterior commissure, and periaqueductal central gray. Additional neuronal labeling was observed postnatally in the
olfactory bulb, cerebral cortex, amygdala, various nuclei of the thalamus, interpeduncular nucleus, linear nucleus of the
raphe, pretectal area and superior colliculus. In the cerebellum, labeling appeared only after P14 in cells of the molecular
cell layer and granular cell layer. The sizes of labeled neurons developed significantly from P4 to P14 in several nuclei.
The distinctive temporal and spatial expression pattern of NADPH-diaphorase implies that the NO/cGMP system may play an important
role in physiological and developmental functions.
Accepted: 8 September 1997 相似文献
30.
报告1例产前超声联合胎儿颅脑磁共振成像(magnetic resonance imaging,MRI)诊断胎儿脑灰质异位合并细丝蛋白A(filamin A,FLNA)基因突变的病例。患者超声检测结果显示侧脑室外壁凹凸不平,颅后窝池宽,透明隔间腔略窄,小脑延髓池轻度增宽。MRI诊断结果为胎儿脑灰质异位合并大枕大池。羊水穿刺获得脱落细胞,采用全外显子测序和基因拷贝数变异(copy number variations,CNV)分析,显示与脑灰质异位疾病相关的FLNA基因外显子出现缺失,其为可能导致脑灰质异位的致病基因。因此,超声结合胎儿颅脑MRI能有效提高脑灰质异位的诊断率,其中染色体检查可筛查出部分致病原因,并对下次妊娠提供帮助。该病例可丰富临床医生对胎儿大脑灰质异位的产前超声检查、合并畸形、临床表现等的认识。 相似文献