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排序方式: 共有392条查询结果,搜索用时 31 毫秒
101.
Endoxin antagonist lessens myocardial ischemia reperfusion injury@柯永胜$Department of Cardiology, Yijishan Hospital, Wannan Medical College, Wuhu, 241001 China
@王德国$Department of Cardiology, Yijishan Hospital, Wannan Medical College, Wuhu, 241001 C 相似文献
102.
目的:监测地戈辛血药浓度。方法;采用放免法监测746例地戈辛治疗慢性心功能不全病人的血药浓度。结果;血药浓度在治疗范围者325例,偏低者99例,高者322例,大于治疗范围者中有12例出现中毒症状。结论:监测地戈辛血药浓度可作为判断药物疗效和中毒的客观指标。 相似文献
103.
COX-2 expression is induced by UVB exposure in human skin: implications for the development of skin cancer 总被引:12,自引:6,他引:12
Buckman SY; Gresham A; Hale P; Hruza G; Anast J; Masferrer J; Pentland AP 《Carcinogenesis》1998,19(5):723-729
Extensive documentation has validated the role of UV irradiation as a tumor
initiator and promoter, inducing both squamous and basal cell carcinomas.
Human epidermis is a tissue which undergoes active metabolism of
arachidonic acid to prostaglandins which is regulated by the action of
prostaglandin H synthase (also known as cyclooxygenase). One mechanism for
the promotional activity of UV light may involve its ability to induce
prostaglandin formation. Work in our laboratory has demonstrated that acute
exposure of human keratinocytes to UVB irradiation results in increased
production of prostaglandin E2 (PGE2). When cultured human keratinocytes
were examined after irradiation with 30 mJ/cm2 UVB in vitro, Western blot
analysis showed a 6-fold increase in COX-2 protein which was evident at 6 h
and peaked 24 h after irradiation. Furthermore, when human subjects were
irradiated on sun- protected skin with up to four times their minimal
erythema dosage (MED) and biopsied 24 h later, upregulation of COX-2
protein expression was observed via immunofluorescence microscopy. RNAase
protection assays supported this observation, showing induction of COX-2
message which peaked at approximately 12 h following irradiation in vitro.
Furthermore, human squamous cell carcinoma biopsies exhibited strongly
enhanced staining for COX-2 protein via immunohistochemistry and Western
analysis when compared to normal non-sun-exposed control skin. Together,
these data demonstrate acute upregulation of COX-2 via UVB irradiation and
suggest the need for further studies of COX-2 expression as a potential
pharmacological target mediating human skin tumor development.
相似文献
104.
Patterns of brain activation in people at risk for Alzheimer's disease 总被引:27,自引:0,他引:27
Bookheimer SY Strojwas MH Cohen MS Saunders AM Pericak-Vance MA Mazziotta JC Small GW 《The New England journal of medicine》2000,343(7):450-456
BACKGROUND: The epsilon4 allele of the apolipoprotein E gene (APOE) is the chief known genetic risk factor for Alzheimer's disease, the most common cause of dementia late in life. To determine the relation between brain responses to tasks requiring memory and the genetic risk of Alzheimer's disease, we performed APOE genotyping and functional magnetic resonance imaging (MRI) of the brain in older persons with intact cognition. METHODS: We studied 30 subjects (age, 47 to 82 years) who were neurologically normal, of whom 16 were carriers of the APOE epsilon4 allele and 14 were homozygous for the APOE epsilon3 allele. The mean age and level of education were similar in the two groups. Patterns of brain activation during functional MRI scanning were determined while subjects memorized and recalled unrelated pairs of words and while subjects rested between such periods. Memory was reassessed in 14 subjects two years later. RESULTS: Both the magnitude and the extent of brain activation during memory-activation tasks in regions affected by Alzheimer's disease, including the left hippocampal, parietal, and prefrontal regions, were greater among the carriers of the APOE epsilon4 allele than among the carriers of the APOE epsilon3 allele. During periods of recall, the carriers of the APOE epsilon4 allele had a greater average increase in signal intensity in the hippocampal region (1.03 percent vs. 0.62 percent, P<0.001) and a greater mean (+/-SD) number of activated regions throughout the brain (15.9+/-6.2 vs. 9.4+/-5.5, P=0.005) than did carriers of the APOE epsilon3 allele. Longitudinal assessment after two years indicated that the degree of base-line brain activation correlated with degree of decline in memory. CONCLUSIONS: Patterns of brain activation during tasks requiring memory differ depending on the genetic risk of Alzheimer's disease and may predict a subsequent decline in memory. 相似文献
105.
A ninth locus (RP18) for autosomal dominant retinitis pigmentosa maps in the pericentromeric region of chromosome 1 总被引:3,自引:1,他引:3
We studied a large Danish family of seven generations in which autosomal
dominant retinitis pigmentosa (adRP), a heterogeneous genetic form of
retinal dystrophy, was segregating. After linkage had been excluded to all
known adRP loci on chromosomes 3q, 6p, 7p, 7q, 8q, 17p, 17q and 19q, a
genome screening was performed. Positive lod scores suggestive of linkage
with values ranging between Z = 1.58-5.36 at theta = 0.04-0.20 were
obtained for eight loci on proximal 1p and 1q. Close linkage without
recombination and a maximum lod score of 7.22 at theta = 0.00 was found
between the adRP locus (RP18) in this family and D1S498 which is on 1q very
near the centromere. Analysis of multiply informative meioses suggests that
in this family D1S534 and D1S305 flank RP18 in interval 1p13-q23. No
linkage has been found to loci from this chromosomal region in six other
medium sized adRP families in which the disease locus has been excluded
from all known chromosomal regions harbouring an adRP gene or locus
suggesting that there is (at least) one further adRP locus to be mapped in
the future.
相似文献
106.
Fragile X (FraX) syndrome is the most common cause of inherited mental retardation. To see whether FRAXA or FRAXE can account for the etiology of some unexplained neurodevelopmental disorders in children, we screened for trinucleotide repeat expansion in a consecutive cohort of 73 Chinese children and their mothers seen in 1995 (group 1) referred for developmental assessment due to developmental delay, language delay, attention deficit hyperactivity disorder, autistic spectrum disorder, mental retardation and/or learning disability. We also screened DNA samples of all five previously diagnosed cytogenetically-positive FraX boys, their mothers and sisters (group 2). A control group of unrelated teenagers and adults were recruited from the community (group 3). In group 1, 3 families (2 mothers and a mother and her son) were found to carry a small premutation allele at FRAXA (premutation frequency = 2%, 3/153 independent X chromosomes), but none had any expansion at FRAXE. In group 2, all 5 FraX boys had full mutation at FRAXA and normal repeat length at FRAXE. In group 3, 1 male has a premutation allele out of 18 males and 59 females tested (premutation frequency of control = 0.7%, 1 out of 136 X chromosomes). For FRAXE screening in group 3, 2 females were carriers (1.5%, 2 out of 136 X chromosomes). Thus, FRAXA and FRAXE cannot account for the etiology of neurodevelopmental disorders in our cohort of Chinese children, and the prevalence of FRAXE mutation in normal Chinese population appears to be higher than reported in the Caucasians. 相似文献
107.
108.
109.
目的 调查中国香港儿童分泌性中耳炎发病率,并且进一步与西方的研究结果做比较。方法 1995-1998年,在中国香港特别行政区随机抽取小学、幼稚园(4-5岁)及幼儿园(2-3岁),对6872名2-7岁儿童进行检查,在校内接受由耳鼻咽喉科专家施行的耳镜检查及由听力学家执行的鼓室导抗测试。为了与西方研究结果作出标准化的比较,根据他们所采用的诊断标准重新计算。结果 在划分为2-3岁、4-5岁及6-7岁的研究对象中,若以耳镜临床诊断作标准,本研究分泌性中耳炎发病率为5.2%-21.6%;若以鼓室导抗图作诊断标准,发病率为7.3%-30.7%。同一组数据,发病率计算结果是会因为采用不同的鼓室导抗图诊断定义而有偏差,但无论是用哪种方法,结果都与西方同龄研究的发病率差异无显著性,而且发病率随年龄增加而下降。结论 香港2-3岁、4-5岁,及6-7岁中国儿童的分泌性中耳炎发病率与西方文献报告没有显著性差异。 相似文献
110.
Pouratian N Bookheimer SY O'Farrell AM Sicotte NL Cannestra AF Becker D Toga AW 《Journal of neurosurgery》2000,93(4):676-681
The organization of language in the brains of multilingual persons remains controversial. The authors investigated language representations in a proficient bilingual patient by using a novel neuroimaging technique, intraoperative optical imaging of intrinsic signals (iOIS), and a visual object naming task. The results indicate that there are cortical areas that are activated by the use of both English and Spanish languages (superior temporal sulcus, superior and middle temporal gyri, and parts of the supramarginal gyrus). In addition, language-specific areas were identified in the supramarginal (Spanish) and precentral (English) gyri. These results suggest that cortical language representations in bilingual persons may consist of both overlapping and distinct components. Furthermore, this study demonstrates the utility of iOIS in detecting topographical segregation of cognitively distinct cortices. 相似文献