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121.
孕妇巨细胞病毒感染对胎儿影响的前瞻性研究 总被引:12,自引:0,他引:12
用酶联免疫吸附试验(ELISA)及聚合酶链反应(PCR)方法对沈阳市450名孕妇进行巨细胞病毒(CMV)筛查,并前瞻性追查到其婴儿100名CMV感染状况。结果孕妇97.11%为既往感染,0.89%为原发感染,11.11%为复发感染,仅2%为易感者。450例中感染组孕妇有畸形儿3例,流产3例,其胎儿感染率与致畸率明显高于对照组。100例母婴检查结果:感染组孕妇所生先天性感染儿比对照组多1.43倍(RR=1.43),感染组有2名低智儿,对照组无。本组早孕原发感染对胎儿危害最大,其宫内传播率为33.3%。感染组孕妇9例感染儿中2例巨细胞包涵体病,7例无症状。为了早期诊断达到优生目的,对孕妇进行CMV筛查是必要的,但筛查过程中发现有活动感染时处理要慎重,最好追查到羊水阳性时考虑终止妊娠。 相似文献
122.
目的 通过随访调查和病毒基因检测,了解母婴阻断后的效果,并研究突破母婴阻断的乙型肝炎病毒基因序列特征,了解病毒母婴传播特点.方法 2003年开始收集临床乙型肝炎病毒表面抗原阳性母亲血清及婴儿血清75对,检测血清学感染指标,取其中母亲与婴儿皆为阳性的血清提取乙型肝炎病毒,扩增包括preS和S基因在内的基因序列片段,序列测定后与标准基因型别比较,确定病毒基因及血清型别,及母婴间病毒核苷酸差异率,及确定a抗原决定簇的氨基酸替代突变率,与免疫成功组进行比较.结果 经血清学检测后共得到母婴血清皆为阳性者4对,包括一对双胞胎,扩增出乙肝病毒基因序列,其中4个乙型肝炎病毒基因型为B型,1个乙型肝炎病毒基因型为C型,其中1对双胞胎婴儿在"a"抗原决定簇出现T143M变异,其余扩增母婴阻断成功病例43例,37例为B型,6例为C型,其中a抗原决定簇发生变异的有3例.结论 母婴阻断失败的儿童中大部分与母亲的基因序列相同,a抗原决定簇变异的比率高于成功组母亲,但差异无统计学意义. 相似文献
123.
Modern Mind-Brain Reading: Psychophysiology, Physiology, and Cognition 总被引:17,自引:0,他引:17
This paper reviews the actual and potential benefits of a marriage between cognitive psychology and psychophysiology. Psychophysiological measures, particularly those of the event-related brain potential, can be used as markers for psychological events and physiological events. Thus, they can serve as "windows" on the mind and as "windows" on the brain. These ideas are illustrated in the context of a series of studies utilizing the lateralized readiness potential, a measure of electrical brain activity that is related to preparation for movement. This measure has been used to illuminate presetting processes that prepare the motor system for action, to demonstrate the presence of the transmission of partial information in the cognitive system, and to identify processes responsible for the inhibition of responses. The lateralized readiness potential appears to reflect activity in motor areas of cortex. Thus, this measure, along with other psychophysiological measures, can be used to understand how the functions of the mind are implemented in the brain. 相似文献
124.
Miniature end-plate currents (m.e.p.c.s) were recorded from frog neuromuscular junctions using a two-electrode voltage clamp. The m.e.p.c. frequency was temporarily elevated following 10 s iontophoretic applications of acetylcholine (ACh) when the junctions were clamped at 100 mV. This post-ACh burst of quanta was also observed at unclamped junctions. At –100 mV, the intensity of the burst was proportional to the amount of current flowing across the end-plate during ACh iontophoresis, but usually did not reach its peak until the end-plate receptor channels were almost completely closed. Addition of 0.5 M TTX to the Ringer's solution, or total replacement of sodium with quanidine, lithium, or methylamine did not inhibit the burst. No burst was observed in Ca2+-free, EGTA solutions, or in Ca2+-free solutions containing 2 mM Mn2+. Sr2+ effectively substituted for Ca2+. Addition of 2 mM Co2+ or Mn2+ to normal Ringer's did not inhibit the burst. Presynaptic muscarinic receptors did not obviously contribute to the burst, since it was not blocked by atropine, nor produced by oxotremorine or pilocarpine. The ACh analogs carbachol and acetyl--methylcholine also produced the burst. The burst was highly dependent on the muscle membrane potential during the period of ACh iontophoresis, becoming more intense at potentials negative to –100 mV and disappearing at –60 mV. The critical importance of the post-synaptic membrane potential suggests that the burst may be due to an action of the muscle end-plate on the motor nerve terminal, possibly by the movement of an anionic substance through open end-plate receptor channels, but this hypothesis does not account for the delay of the burst until near the end of the ACh-induced end-plate current. 相似文献
125.
With the investigations on pregnant women and newbornsinfected withToxoplasma, rubella virus, cytomegalovirus,herpes simplex virus (TORCH), it was found that humanparvovirus B19 (B19 virus), which belongs to the familyParvoviridae and the genus Erythrovir… 相似文献
126.
不同方法注射乙肝免疫球蛋白阻断HBsAg、HBeAg双阳性孕妇母婴传播的研究 总被引:1,自引:0,他引:1
目的研究不同方法注射乙肝免疫球蛋白(HBIG)对HBsAg伴HBeAg双阳性孕妇的乙肝病毒(HBV)宫内感染阻断作用。方法将137例双阳性孕妇分为4组:A组从孕16周起注射HBIG,B组从孕20周起注射HBIG,C组从孕28周起注射HBIG,A、B、C 3组孕妇每次均注射HBIG200IU,并间隔4周1次,直至临产;D组作为对照组,不注射HBIG;出生后4组所有新生儿均于16h内和生后2周注射HBIG200IU,满月起按1、2、7月龄分别接种乙肝疫苗,并定期随访。结果新生儿出生时外周血测得HBsAg,A组与B组无显著性差别(P>0.05),A、B 2组与C组、D组以及C组与D组均有显著性差别(P均<0.05);经随访A、B、C、D 4组HBV宫内感染率分别为5.6%、5.3%、19.4%和48.5%,母婴传播阻断率A组与B组无显著差异(P>0.05),A组和B组均显著高于C组和D组、C组显著高于D组(P均<0.05)。结论对HBsAg伴HBeAg双阳性孕妇,选择孕20周开始注射HBIG比较合适,阻断率最高,能有效减少HBV宫内感染的发生率。 相似文献
127.
Martínez G Ropero C Funes A Flores E Blotta C Landa AI Gargiulo PA 《Physiology & behavior》2002,76(2):219-224
Effect of blocking N-methyl-D-aspartic acid (NMDA) and non-NMDA-glutamatergic receptors on performance in the plus-maze was studied in male rats bilaterally cannulated into the nucleus accumbens (Acc). Rats were divided into seven groups that received either 1 microl injections of saline, (+/-)2-amino-7-phosphonoheptanoic acid (AP-7, 0.2, 0.5, or 1 microg) or 2,3 dioxo-6-nitro-1,2,3,4,tetrahydrobenzo-(f)quinoxaline-7-sulphonamide disodium (NBQX, 0.2, 0.5, or 1 microg) 15 min before testing. Time spent in open arm, time per entry, end arrivals, open, closed, and total arm entries, relationship between open-, closed-, and total arm entries, rearing, face-, head-, and body grooming, and number of fecal boli were recorded. Time spent in the open arm increased under AP-7 (0.5 and 1 microg; P<.01) and NBQX (1 microg; P<.05) treatment, whereas time per entry was increased only with AP-7 (1 microg; P<.05). Open arm entries were increased by the intermediate doses of AP-7 (0.5 microg; P<.01) and NBQX (0.5 microg; P<.05); end arrivals were increased by the intermediate dose of AP-7 (0.5 microg/1 microl, P<.05). The frequency of rearing, grooming, and closed arm entries was not affected by the treatment. We conclude that NMDA and non-NMDA-glutamatergic blockade in the Acc lead to a behavioral disinhibition of cortical influences with the median doses, but that at higher doses the blockers have an anxiolytic-like effect. 相似文献
128.
极低频磁场对胞内钙振荡影响的机理分析 总被引:4,自引:0,他引:4
基于双钙库模型,本文以离子跨过细胞膜、细胞器膜迁移的几率作为细胞对电磁场的响应因子,来调制流过膜通道的离子的速率,进而影响细胞内钙离子的浓度。数值分析表明:在极低频磁场的作用下,一定能量因子下的频率条件或是一定频率因子下的能量条件可引起钙振荡形式的变化;窗效应是频率因子和能量因子共同作用的结果。 相似文献
129.
V Bogomolski-Yahalom E Granot N Linder R Adler S Korman N Manny R Tur-Kaspa D Shouval 《Journal of medical virology》1991,34(4):217-222
Israel has no official prevention policy at present against perinatal and horizontal transmission of hepatitis B virus (HBV) infection in newborns and children at risk. The present study was designed to assess the prevalence of HBV carrier state in a population of 11,123 pregnant women at term. Among this population (mean age 29.7 +/- 5.9), 98 women (0.88%) were found to be asymptomatic HBsAg+ carriers, and 97% of these carriers were anti-HBe+. Evidence for HBV replication, as determined by serum HBV-DNA, was established in 6.6% of the HBsAg+/anti-HBe+ population. The HBsAg carrier rate was strongly influenced by religion, continent, and country of birth of the carrier mothers. The highest relative carrier rate was found among women of Moslem origin (4.3%), as compared to Jewish women (0.67%). Most carrier women were born in Israel (56.1%) to mothers who had emigrated from regions with intermediate or high endemicity of HBV, such as North Africa or the Middle East. In these groups, the HBsAg carrier rate ranged between 1.2 and 3.0%. Ninety-three percent of newborns receiving passive/active vaccination against HBV developed protective levels of anti-HBs. Finally, evidence for horizontal transmission of HBV was found in 19.3% of 83 non-vaccinated children in families of HBsAg carriers. The present study therefore establishes HBsAg prevalence rates in specific risk groups of women at term and confirms the need for an official policy on immunization against HBV in Israel. Since over 50% of women at term belong to the defined risk groups, universal active vaccination of the entire newborn population each year is suggested as the most rational and needed policy in Israel. 相似文献
130.
Schaefer M 《Pflügers Archiv : European journal of physiology》2005,451(1):35-42
Mammalian homologues of the Drosophila melanogaster transient receptor potential (TRP) channels are the second largest cation channel family within the superfamily of hexahelical cation channels. Most mammalian TRP channels function as homooligomers and mediate mono- or divalent cation entry upon activation by a variety of stimuli. Because native TRP channels may be multimeric proteins of possibly complex composition, it is difficult to compare cation conductances in native tissues to those of clearly defined homomeric TRP channel complexes in living cells. Therefore, the possibility of heteromeric TRP channel assembly has been investigated in recent years by several groups. As a major conclusion of these studies, most heteromeric TRP channel complexes appear to consist of subunit combinations only within relatively narrow confines of phylogenetic subfamilies. Although the general capability of heteromer formation between closely related TRP channel subunits is now clearly established, we are only beginning to understand whether these heteromeric complexes are of physiological significance. This review summarizes the current knowledge on the promiscuity and specificity of the assembly of channel complexes composed of TRPC-, TRPV- and TRPM-subunits of mammalian TRP channels. 相似文献