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排序方式: 共有73条查询结果,搜索用时 15 毫秒
1.
More than forty years after the first birth following in vitro fertilization (IVF), the success rates of IVF and of IVF-derived assisted reproduction techniques (ART) still remain relatively low. Interindividual differences between infertile couples and the nature of the problems underlying their infertility appear to be underestimated nowadays. Consequently, the molecular basis of each couple’s reproductive function and of its disturbances is needed to offer an individualized diagnostic and therapeutic approaches to each couple, instead of applying a standard or minimally adapted protocols to everybody. Interindividual differences include sperm and oocyte function and health status, early (preimplantation) embryonic development, the optimal window of uterine receptivity for the implanting embryo, the function of the corpus luteum as the main source of progesterone production during the first days of pregnancy, the timing of the subsequent luteoplacental shift in progesterone production, and aberrant reactions of the uterine immune cells to the implanting and recently implanted embryos. In this article, the molecular basis that underlies each of these abnormalities is reviewed and discussed, with the aim to design specific treatment options to be used for each of them.  相似文献   
2.
The present study aimed to investigate the relationship between the concentrations of bisphenols residues in the amniotic fluid (AF) samples collected during amniocentesis and fetal chromosomal abnormalities in pregnant women. A total of 33 pregnant Polish women aged between 24 and 44 years, and screened to detect high risk for chromosomal defects in the first trimester, were included in this study. Samples were collected from these patients during routine diagnostic and treatment procedures at mid-gestation. The concentrations of various bisphenols residues in the samples were determined by liquid chromatography coupled with triple quadrupole tandem mass spectrometry (LC-ESI-QqQ-MS/MS). Residues of eight analytes (BPS, BPF, BPA, BPAF, BADGE, BADGE•2H2O, BADGE•H2O•HCl and BADGE•2HCl) were detected in amniotic fluid samples in the range 0.69 ng/mL to 3.38 ng/mL. Fetuses with chromosomal abnormalities showed a slightly higher frequency of occurrence of selected bisphenols residues in the AF samples collected between 15–26 weeks of pregnancies. Finally, the proposed method was applied in the simultaneous determination of several endocrine-disrupting chemicals from bisphenol group in 33 human AF samples. BADGE•H2O•HCl has been identified in the AF samples taken from women older than average in the examined group. The number of detected compounds has been significant for the following analytes: BPS, BPAF, BADGE•H2O•HCl and BADGE. The proposed method may be an attractive alternative for application in large-scale human biomonitoring studies.  相似文献   
3.
Psychopathy is associated with abnormalities in attention and orienting. However, few studies have examined the neural systems underlying these processes. To address this issue, the authors recorded event-related potentials (ERPs) while 80 incarcerated men, classified as psychopathic or nonpsychopathic via the Hare Psychopathy Checklist-Revised (R. D. Hare, 1991, 2003), completed an auditory oddball task. Consistent with hypotheses, processing of targets elicited larger frontocentral negativities (N550) in psychopaths than in nonpsychopaths. Psychopaths also showed an enlarged N2 and reduced P3 during target detection. Similar ERP modulations have been reported in patients with amygdala and temporal lobe damage. The data are interpreted as supporting the hypothesis that psychopathy may be related to dysfunction of the paralimbic system--a system that includes parts of the temporal and frontal lobes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
Motor abnormalities occur in schizophrenia (SZ) and may arise from striatal dysfunction. This study examined whether the pattern of performance on simple and complex motor abilities in SZ was similar to that of patients with Parkinson's disease (PD). Quantitative tests of speeded movement and motor and cognitive sequencing were used to assess 25 SZ, 16 PD, and 84 normal controls (NCs). Sequencing performance was also examined with motor rigidity taken into account. Compared with the NC group, the SZ and PD groups were impaired on measures of motor rigidity and motor sequencing. With rigidity accounted for, the SZ group was significantly more impaired than the PD group on motor sequencing; cognitive and motor processes contributed to the motor deficit. Cognitive sequencing performance predicted motor sequencing performance in PD but not SZ. Although both SZ and PD resulted in significant motor and cognitive sequencing deficits, the pattern and correlates of these deficits differ, suggesting that the affected neural systems underlying motor deficits in SZ are different from those involved in PD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
目的探讨唐氏儿血清学筛查及超声检查在诊断胎儿染色体异常中的价值。方法对近3年我院5907例孕妇血清学筛查结果及40例因胎儿结构异常进行染色体检查的病例进行回顾性分析。结果5907例孕妇中检出唐氏儿高危病例521例(含82例年龄≥35岁的孕妇),阳性率8.82%,共有198例进行了羊膜腔穿刺,穿刺率38%。40例胎儿畸形病例引产时取胎儿血或羊水进行染色体检查,成功率100%。共诊断17例胎儿染色体异常,其中21三体8例,18三体3例,13三体1例,1Turner综合征1例,Klinefelter综合征1例,18染色体短臂微缺失1例,9号染色体臂间倒位2例(1例来源于母亲)。17例中有8例进行了唐氏儿血清学筛查,5例异常,11例超声检查胎儿有结构异常。与染色体异常有关的畸形主要包括多发畸形、心脏畸形、胎儿水肿、消化道畸形等。结论应加强宣教,提高唐氏儿血清学筛查及高风险孕妇羊膜腔穿刺率;超声检查在胎儿染色体异常诊断中具有重要价值。  相似文献   
6.
Socioemotional abnormalities, including decreased social interactions and increased self-directed activity, were reported when rhesus monkeys with neonatal ablations of either the medial temporal lobe (AH) or the inferior temporal cortex (TE) were paired with unoperated peers at two and six months of age, though these abnormalities were more severe in Group AH (Bachevalier et al., 2001). As adults (Experiment 1), the monkeys were re-evaluated in the same dyads and their reactivity to novel toys, social status, and reactions to separation were also assessed. Group TE now showed only few if any of the abnormal behaviors observed in infancy. In contrast, Group AH continued to display decreased social interactions and increased self-directed activity and showed also increased submission and reduced responses to separation, but normal reactivity to novel toys. To determine whether this degree of socioemotional impairment was less severe than that produced by the same damage in adulthood, we assessed dyadic social interactions of monkeys raised until adulthood in laboratory conditions similar to those in Experiment 1 and then given the AH ablations (Experiment 2). Two months postoperatively these monkeys showed a small reduction in social interactions that became more pronounced six months postoperatively, yet remained less severe than that seen in the infant-lesioned monkeys. No other socioemotional effects, except for an increase in food/water consumption, were observed. The finding that neonatal AH lesions produce more severe socioemotional disturbances than the same lesion in adulthood is the reverse of the effect commonly reported for other cognitive functions after cerebral damage. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
目的:观察585nm脉冲染料激光治疗血管性疾病所致的副作用。方法:分析500例经585nm脉冲染料激光治疗后的副反应。结果:500例接受治疗的患者中发生副反应者89例。其中色素沉着35例、色素减退12例、萎缩性瘢痕40例、增生性瘢痕2例。出现副反应与疾病种类、治疗能量无关,与治疗次数有关。结论:585nm脉冲染料激光治疗血管性疾病无连续激光治疗后所致的增生性瘢痕、持续性色素沉着等副作用,用于治疗血管性疾病是比较安全的。  相似文献   
8.
自然流产是妊娠并发症,指妊娠在28周之前自然终止,其发病率在15%~40%。近年来在辅助生育技术的使用中,同样面临着较高的自然流产率的问题。自然流产的病因十分复杂,除了遗传因素以外,还包括解剖因素、内分泌因素、感染因素、环境因素、免疫因素、血栓前状态以及母体的全身性疾病等等。自然流产的细胞遗传学研究,主要在两个方面,一是胚胎染色体的异常,包括染色体数量异常和结构异常;二是夫妇染色体的异常。在自然流产中胚胎染色体异常的检出率在60%左右,且随着流产次数的增加,染色体异常的比例下降。其中大部分为胚胎染色体数目异常如三体、三倍体及X单体等,较少为染色体结构异常,包括染色体断裂、倒置、缺失和易位等。在自然流产的夫妇中,尤其是反复自然流产的夫妇,其染色体异常的检出率在8%左右,且随着流产次数的增加异常的比例升高。成人染色体的异常多为染色体的平衡易位。随着细胞遗传学的检测技术的发展,从传统染色体核型分析和荧光原位杂交技术到染色体微阵列芯片分析、第二代测序技术即高通量测序技术的相继应用,使得自然流产的遗传学方面的研究更加深入。自然流产的细胞遗传学的研究进展,对于自然流产的病因研究以及生育指导有着非常重要的意义。  相似文献   
9.
1IntroductionTheioallingradiationoflowdosesandlowdose-ratesarecloselyrelatedtotheenvironmentofhUmanproductionandlife.Hencetheeffectsofionizingradiationonorgedsznsorvariouscellshaveincreasinglybeenconcerned.Olivierietal.[1]foundin1984thathUInanperipheralbloodlylnphocytesexposedtolowdosesof3H-TdRorX-raybecomerefractorytotheinductionofforomosomaldamagebysubsequenthighdoseofX-rayradiation.Thisphenomenonissaidtobeadaptiveresponse.Sincethenmanystudiesregardingtheadaptiveresponseofcellsinducedinb…  相似文献   
10.
"We believe that the heterosexual affectional system in the rhesus monkey, like all the other affectional systems, goes through a series of developmental stages—an infantile heterosexual stage, a preadolescent stage, and an adolescent and mature heterosexual stage." Isolation-raised monkeys later displayed severe social abnormalities—a sociopathic syndrome. Monkeys raised with surrogate mothers—rejecting wire frame mothers, air-blast mothers, and infant-shaking mothers—have seldom displayed normal sex behavior. "Month after month female monkeys that never knew a real mother, themselves become mothers—helpless, hopeless, heartless mothers devoid, or almost devoid of any maternal feeling." (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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