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101.
ABSTRACT

In this study we compared the neuropsychological profile of phenylketonuria (PKU) and human immunodeficiency virus (HIV) to examine the specificity of the executive function (EF) impairment reported in these two patologies. A total of 55 age-matched children and adolescents were assessed, including 11 patients with PKU, 16 patients with HIV and 28 healthy controls, underwent a neuropsychological assessment. Although neither the PKU nor the HIV group scored below the normative ranges, both groups showed lower scores in neuropsychological tests engaging EFs than controls. In addition, compared to patients with PKU the HIV group performed significantly worse in the Trail-Making Test A, Corsi Span and Verbal Fluency. These findings suggest that EF impairments in PKU (a) are limited to EFs (i.e., working memory and attentional shifting), (b) are not simply due to generalized processing speed deficits and (c) overlap partially with EF impairments found in a chronic medical developmental disorder.  相似文献   
102.
OBJECTIVE: To describe auditory perceptual, pre-attentive, attention-related and cognitive processes along lifespan in normal people by a simple auditory oddball paradigm easily usable in clinical practice. METHODS: ERPs were recorded in 72 normal subjects. Four blocks of tones were delivered (20% rare 2,000 Hz and 80% frequent 1,000 Hz). In the former two blocks, subjects performed a concomitant distracting visual search task (distracted condition); in the latter two blocks, they had to attend the occurrence of the rare tones (active condition). Latency and amplitude of ERPs were analyzed according to age, gender, educational level and repetition. RESULTS: N100 amplitude was greater in active than in distracted condition. MMN amplitude decreased with age. N2b and P300 latencies increased with age, while their amplitudes decreased. Females produced greater P300 than males. In the elderly, P300 latency was found to be longer in the second block than in the first one. CONCLUSIONS: N100 and MMN were found to be less affected by age than N2b and P300. When repeated, P300 showed increased latency in elderly subjects. SIGNIFICANCE: The protocol detected the higher influence of aging on late cognitive processes than on the perceptual and pre-attentive ones. Age-adjusted normative data were produced.  相似文献   
103.
104.
青海省达日县棘球蚴病流行病学调查   总被引:2,自引:0,他引:2       下载免费PDF全文
目的 分析青海省果洛藏族自治州达日县棘球蚴病的流行分布现状,为制定预防控制措施提供科学依据。 方法 于2007年8~9月对达日县6个乡各2~3个自然村的3周岁以上常驻牧民分别用B超、间接红细胞凝集试验(IHA)和间接ELISA法(重组Ag B和Em 18抗原)检查两型棘球蚴病患病和感染情况。并调查当地啮齿类动物、牦牛、绵羊和野犬的感染情况,对采集的棘球绦虫和棘球蚴用PCR-RFLP方法进行虫种鉴定,并确定其基因型。收集牧民的家犬粪便,用双抗体夹心法检测粪抗原阳性率。 结果 共调查牧民1 723人,B超查出棘球蚴病患者236例(占13.7%),其中囊型和泡型棘球蚴病患病率分别为5.5%(95/1 723)和8.2%(141/1 723)。男、女性棘球蚴病患病率分别为11.6%和16.0%(χ 2=7.0,P<0.05)。家犬粪抗原阳性率为11.3%(31/275)。剖检9只无主犬,其中5只棘球绦虫感染阳性,对检获的虫体经PCR-RFLP鉴定,1只犬感染细粒棘球绦虫,基因型为G1,4只犬感染多房棘球绦虫。牦牛、绵羊的细粒棘球蚴感染率分别为26.4%(14/53)和5/16,对从牦牛、绵羊检获的细粒棘球蚴经PCR-RFLP鉴定,基因型均为G1。捕获高原鼠兔239只,石渠棘球绦虫感染率为11.3%(27/239)。 结论 达日县存在细粒棘球绦虫、多房棘球绦虫和石渠棘球绦虫的分布,泡型和囊型棘球蚴病在人群中严重流行,犬是细粒棘球绦虫和多房棘球绦虫主要传染源。  相似文献   
105.
Yang  SY; Coleman  PS; Dupont  B 《Blood》1982,59(4):747-755
R-type vitamin B12 binding proteins (R proteins) from human granulocytes, erythrocytes, plasma, and other body fluids were characterized by isoprotein banding patterns on autoradiograms after resolution via thin-layer polyacrylamide isoelectric focusing (IEF) gel electrophoresis. R proteins obtained from various tissue sources in a given individual show tissue-specific electrophoretic patterns. The desialated R proteins obtained following in vitro treatment with neuraminidase are, however, the same for any given individual and do not show tissue specificity. The differences seen in native R proteins (i.e., transcobalamin I, III, and others) obtained from different tissues are due to variations only in the sialic acid content. Granulocytes from patients with chronic myelogenous leukemia (CML) contain both TC I and TC III, and these R proteins can be released in vitro by lithium stimulation. Normal granulocytes contain only TC III. Differences in desialated R proteins from individual to individual are due to a genetic polymorphism controlled by a single genetic locus (designated TCR) with two alleles, 1 and 2, which are found to be codominantly expressed in heterozygous individuals. The allelic variants of the desialated R proteins found in different blood cells and body fluids are controlled by only one genetic locus.  相似文献   
106.
青海省班玛县泡型和囊型包虫病流行现状调查分析   总被引:8,自引:0,他引:8  
包虫病是由细粒棘球绦虫和多房棘球绦虫的幼虫寄生而引起的人兽共患寄生虫病,主要流行于我国西北地区的新疆、青海、内蒙、宁夏、西藏、四川西部、甘肃等地。青海是青藏高原的主体省份。存在包虫病的高度流行,其中泡型包虫病是一种严重危害人体健康可致死的寄生虫病,为了解果洛州的班玛县两型包虫病的流行分布状况,于2004年8~9月进行了调查。  相似文献   
107.
Nitric oxide has been implicated as a mediator of inflammatory arthritis, and recent work has shown that pro-inflammatory cytokines stimulate NO production in vitro by activation of the inducible nitric oxide synthase (iNOS) pathway. In order to identify the cellular sources of NO production within the joint, we have used immunohistochemical techniques to study the distribution of iNOS in synovium and cartilage from normal and diseased joints. iNOS was most strongly expressed in the synovial lining layer, subsynovium, vascular smooth muscle and chondrocytes from patients with rheumatoid arthritis (RA). Analysis of serial sections, coupled with double immunofluorescent staining, showed that the CD68+ macrophages in the synovial lining layer and, to a lesser extent, fibroblasts were the predominant source of iNOS within synovium, whereas T cells, B cells and neutrophils were negative. A similar pattern of iNOS staining was seen in osteoarthritis, but fewer cells were iNOS positive and the intensity of staining, particularly in cartilage, was much weaker than in RA. In contrast, no evidence of iNOS was detected in non- inflammatory synovium or in cartilage derived from normal joints (fractured neck of femur). In conclusion, these data support the hypothesis that synovium and cartilage are important sources of increased NO production in patients with inflammatory arthritis. Localization of iNOS at these sites within the inflamed joint raises the possibility that increased local production of NO may contribute to the pathogenesis of inflammatory arthritis by increasing synovial blood flow and by modulating cellular function within synovium and articular cartilage.   相似文献   
108.
Grant  S; Traylor  R; Pettit  GR; Lin  PS 《Blood》1994,83(3):663-667
We have examined the in vivo radioprotective effects of the macrocyclic lactone protein kinase C (PK-C) activator, bryostatin 1, administered either alone or in conjunction with recombinant murine granulocyte- macrophage colony-stimulating factor (rmGM-CSF), in Balb/c and C3H/HeN mice subjected to lethal total body irradiation (TBI). When administered alone on a divided dose schedule (24 hours and 30 minutes before TBI), rmGM-CSF (20 micrograms/kg) was ineffective in increasing survival in either strain. However, in Balb/c mice, bryostatin 1 alone (1 microgram) permitted the long-term survival (60 days) of 70% of the animals following TBI, and 80% when administered in conjunction with rmGM-CSF. Bryostatin 1 administered alone according to this schedule exerted minimal radioprotective effects in C3H/HeN mice, but, when combined with a subeffective dose of rmGM-CSF, allowed 50% of the animals to survive. Treatment of Balb/c mice with bryostatin 1 administered as a single dose 4 hours before TBI resulted in a 20% survival rate, and 45% when administered with rmGM-CSF; corresponding values for the C3H/HeN strain were 60% and 40%, respectively. Lastly, the survival rates of Balb/c mice treated with bryostatin 1 administered as a single dose 4 hours following TBI was 20%, and 25% with rmGM-CSF; corresponding values were 50% and 25% for C3H/HeN mice. These findings indicate that the PK-C activator bryostatin 1 exhibits intrinsic in vivo radioprotective effects in lethally irradiated Balb/c and C3H/HeN mice, and may, under some circumstances, augment the radioprotective capacity of rmGM-CSF. They also underscore the critical role that strain differences and scheduling considerations play in determining the in vivo radioprotective capacity of bryostatin 1, as well as its interactions with rmGM-CSF.  相似文献   
109.
Bone marrow transplantation in patients aged 45 years and older   总被引:5,自引:8,他引:5  
Increasing age has been reported to be a poor prognostic factor for survival after bone marrow transplantation. We evaluated causes of death and frequency and type of complications after marrow grafting in 24 syngeneic and 39 allogeneic recipients who were 45 to 68 years old at the time of transplant. Most patients were in an advanced stage of hematologic malignancy. Among patients given syngeneic transplants, actuarial disease-free survival at 7 years is 20%. The major causes of death were relapse of leukemia and idiopathic interstitial pneumonia. Among allogeneic recipients, 9 (23%) are currently alive, and actuarial disease-free survival at 7 years is 11%. Cytomegalovirus pneumonia and septicemia were the most frequent causes of death. Patients over 50 years of age had the poorest survival rate (1/13), but many of these were transplanted in an advanced stage of their disease. However, among 12 patients transplanted while in remission or at an early stage of their disease, 5 are surviving 65 to 1,160 days after transplantation, with an actuarial survival rate of 22% at 3 years. This is in contrast to those who received their transplant in relapse: 2 out of 20 patients (10%) became long-term survivors, with a probability of survival of 15% at 3 years. The actuarial incidence of grade II through IV acute graft- v-host disease (GVHD) was 30% for allogeneic recipients 45 to 50 years of age. This was not significantly different from the incidence in younger patients. In patients 51 to 62 years of age, the actuarial incidence of acute GVHD was 79%; however, this group included three partially HLA-mismatched transplants. Ten of 15 patients surviving at least 3 months developed chronic GVHD. These results suggest that marrow transplantation is feasible and should be considered in patients over 45 years, especially if recipients are in good clinical condition and are at an early stage of their disease, such as the chronic phase of chronic myelogenous leukemia and preleukemia. For patients more than 50 years of age, allogeneic marrow grafting cannot presently be considered first-line therapy.  相似文献   
110.
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