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991.
Huang XH Loimaala A Nenonen A Mercuri M Vuori I Pasanen M Oja P Bond G Koivula T Hiltunen TP Nikkari T Lehtimäki T 《Journal of molecular medicine (Berlin, Germany)》1999,77(12):853-858
The insertion/deletion (I/D) polymorphism of the human angiotensin-converting enzyme (ACE) gene is a major determinant of circulating ACE levels. The D allele has been suggested to be a potent risk factor for coronary artery disease; however, the effect of the ACE gene on carotid atherosclerosis remains controversial. We therefore studied the relationship between the ACE gene I/D polymorphism and carotid artery intima-media thickness (IMT). A random sample of 300 men aged 50-59 years living in southern Finland were selected, and 233 agreed to participate (74%). Data were collected in 219 subjects. Quantitative B-mode ultrasonography was used to measure the maximum near and far wall IMT of right and left common, bifurcation, and internal carotid artery. The mean maximum IMT (overall mean) was calculated as the mean of 12 maximum IMTs at 12 standard sites. Patients with an IMT higher than 1.7 mm in at least one of 12 standard sites were assumed to have carotid atherosclerosis. The I/D polymorphism was determined by polymerase chain reaction. Overestimation of the frequency of the DD genotype was eliminated by insertion-specific primer and the inclusion of 5% dimethylsulfoxide. No significant differences were found in carotid wall thickness between the three genotypes; the overall mean IMT were 1.18 +/- 0.30, 1.22 +/- 0.24, and 1.08 +/- 0.40 mm in genotypes of II, ID, and DD, respectively. Similarly, the ACE genotypes and allele frequencies did not differ significantly between the subjects with and those without carotid atherosclerosis. There was no association in the subgroups among only nonsmoking subjects or subjects without chronic medication. The present data indicate that the I/D polymorphism of the ACE gene is not related to carotid IMT and is unlikely to play a major role in carotid atherosclerosis. 相似文献
992.
目的:探讨肿瘤标志物甲胎蛋白(AFP)、α-L-岩藻糖苷酶(AFU)、铁蛋白(SF)在原发性肝癌(PHC)诊断中的应用价值。方法:对78例PHC患者、46例良性肝病患者及45例正常人的血清AFP、AFU、SF进行同步检测分析。结果:PHC组血清AFP、AFU、SF的水平显著高于健康对照组及良性肝病组(P<0.05)。三种肿瘤标志物的联检阳性率为93.6%,较AFP、AFU、SF单项检测时有明显提高(P<0.05)。结论:肿瘤标志物AFP、AFU、SF对PHC有一定的诊断价值。三种肿瘤标志物联检可提高诊断PHC的阳性诊断率。 相似文献
993.
颞骨内面神经管的解剖测量及其临床意义 总被引:3,自引:0,他引:3
目的为避免中耳手术中对面神经的损伤。方法对50例(100侧)成人尸头颞骨内面神经管进行解剖测量。结果面神经管迷路段为4.53±1.21mm,鼓室段为9.32±1.25mm,乳突段为13.25±1.53mm,面神经管总长为29.86±0.57mm。结论熟悉颞骨内面神经管的解剖结构,可避免对面神经的损伤,减少和避免面瘫的发生。 相似文献
994.
Neonatal sepsis in the neonatal intensive care unit: characteristics of early versus late onset. 总被引:1,自引:0,他引:1
Jia-Horng Jiang Nan-Chang Chiu Fu-Yang Huang Hsin-An Kao Chyong-Hsin Hsu Han-Yang Hung Jui-Hsing Chang Chun-Chih Peng 《Journal of microbiology, immunology, and infection》2004,37(5):301-306
Neonatal sepsis is a major cause of death in newborns despite sophisticated neonatal intensive care. This retrospective study reviewed the clinical characteristics of cases of culture-proven sepsis in a neonatal intensive care unit from January 1992 to December 2001. Patients were divided into those with onset of sepsis in the first 7 days of life (early-onset group) and those with onset after the seventh day of life (late-onset group). A total of 270 cases with 325 episodes of sepsis and 353 isolated pathogens were identified and included in the study. The male-to-female ratio was 1.4. The majority of cases of sepsis occurred in low birth weight (75.9%) and premature babies (76.7%). Late onset occurred in 71.9% of cases. Patients with late onset had a lower mortality rate than those with early onset (11.3% vs 28.9%). Coagulase-negative staphylococci (20.1%) was the most common organism isolated, but infection with Pseudomonas aeruginosa was associated with the highest morality rate (55.0%). Late-onset sepsis was significantly more common in very low birth weight and premature infants. The most frequently encountered pathogens in the early-onset group were group B streptococci (GBS) and Escherichia coli, while in the late-onset group, the organisms were coagulase-negative staphylococci and Enterobacteriaceae, including E. coli, Klebsiella pneumoniae, and Acinetobacter baumannii. GBS infection resulted in the highest mortality when the onset of sepsis was within the first 24 hours of life. 相似文献
995.
High-Throughput Generation of P. falciparum Functional Molecules by Recombinational Cloning 总被引:2,自引:0,他引:2 下载免费PDF全文
Joo Carlos Aguiar Joshua LaBaer Peter L. Blair Victoria Y. Shamailova Malvika Koundinya Joshua A. Russell Fengying Huang Wenhong Mar Robert M. Anthony Adam Witney Sonia R. Caruana Leonardo Brizuela John B. Sacci Jr. Stephen L. Hoffman Daniel J. Carucci 《Genome research》2004,14(10B):2076-2082
Large-scale functional genomics studies for malaria vaccine and drug development will depend on the generation of molecular tools to study protein expression. We examined the feasibility of a high-throughput cloning approach using the Gateway system to create a large set of expression clones encoding Plasmodium falciparum single-exon genes. Master clones and their ORFs were transferred en masse to multiple expression vectors. Target genes (n = 303) were selected using specific sets of criteria, including stage expression and secondary structure. Upon screening four colonies per capture reaction, we achieved 84% cloning efficiency. The genes were subcloned in parallel into three expression vectors: a DNA vaccine vector and two protein expression vectors. These transfers yielded a 100% success rate without any observed recombination based on single colony screening. The functional expression of 95 genes was evaluated in mice with DNA vaccine constructs to generate antibody against various stages of the parasite. From these, 19 induced antibody titers against the erythrocytic stages and three against sporozoite stages. We have overcome the potential limitation of producing large P. falciparum clone sets in multiple expression vectors. This approach represents a powerful technique for the production of molecular reagents for genome-wide functional analysis of the P. falciparum genome and will provide for a resource for the malaria resource community distributed through public repositories. 相似文献
996.
Chen JJ Huang JC Shirtliff M Briscoe E Ali S Cesani F Paar D Cloyd MW 《Journal of leukocyte biology》2002,71(2):271-278
Recent studies have provided evidence that macrophages from Th1-prone mouse strains respond with an M1 profile, and macrophages from Th2-prone mouse strains respond with an M2 profile, characterized by the dominant production of NO or TGF-beta 1, respectively. We have shown that peritoneal macrophages from IL-12p40 gene knockout mice have a bias toward the M2 profile, spontaneously secreting large amounts of TGF-beta 1 and responding to rIFN-gamma with weak NO production. Moreover, IL-12p40KO macrophages are more permissive to Trypanosoma cruzi replication than their wild-type littermate cells. Prolonged incubation with rIL-12 fails to reverse the M2 polarization of IL-12p40KO macrophages. However, TGF-beta 1 is directly implicated in sustaining the M2 profile because its inhibition increases NO release from IL-12p40KO macrophages. IFN-gamma deficiency is apparently not the reason for TGF-beta 1 up-regulation, because rIFN-gamma KO macrophages produce normal amounts of this cytokine. These findings raise the possibility that IL-12 has a central role in driving macrophage polarization, regulating their intrinsic ability to respond against intracellular parasites. 相似文献
997.
Chih-Kang Huang Alina Dulau Chiao-Ju Su-Rick Qiulu Pan 《Diagnostic molecular pathology》2007,16(1):50-53
UDP glucuronosyltransferase (UGT) 1A1 gene promoter polymorphism can affect the expression level of the UGT 1A1 enzyme. The polymorphism consists of an insertion of a TA nucleotide sequence into a (TA)6TAA sequence in the gene promoter resulting in (TA)7TAA (UGT1A1*28). This results in a reduced UGT 1A1 expression with 70% less glucuronidation capacity for bilirubin and other UGT1A1 substrates. Other polymorphisms include (TA)8TAA (UGT1A1*37) and (TA)5TAA (UGT1A1*36). The longer the TA repeats the lower the enzyme expression level. The anticancer agent irinotecan is metabolized to the active SN-38, which is further glucuronidated and detoxified by UGT 1A1. Decreased glucuronidation leads to SN-38 accumulation with severe neutropenia and diarrhea. We have developed a rapid polymerase chain reaction (PCR)-based detection of all length polymorphisms in the UGT 1A1 gene promoter. It uses PCR and DNA fragment analysis using an ABI Genetic Analyzer. Thirty-two blood samples were analyzed for UGT 1A1 promoter polymorphism. We found 2 (TA)(5)TAA/(TA)(5)TAA, 4 (TA)(5)TAA/(TA)(6)TAA, 2 (TA)(5)TAA/(TA)(7)TAA, 9 (TA)(6)TAA/(TA)(6)TAA, 11 (TA)(6)TAA/(TA)(7)TAA, 2 (TA)(7)TAA/(TA)(7)TAA, and 2 (TA)(7)TAA/(TA)(8)TAA in our sample group. To confirm the results, 6 samples with different repeats were also analyzed by DNA sequencing method. This is a rapid and reliable method for analysis of the promoter length polymorphisms of UGT 1A1 gene. 相似文献
998.
999.
应用地高辛标记探针原位杂交法和单克隆抗HCV-NS3-HRP建立直接酶标免疫组化法分别测定52例肝炎患者肝组织HCVRNA和HCAg-NS3。结果抗HCV阳性组HCVRNA检出率57.1%(16/28),HCAg-NS3检出率53.6%(15/28);抗HCV阴性组其两项检出率均为12.5%(3/24)。肝组织中HCVRNA阳性物呈蓝紫色细小颗粒存在于肝细胞核或胞浆内,其在肝小叶中的分布可分为3型,即弥漫型、局灶型、散在型。肝组织中HCAg-NS3阳性物呈棕黄色细小颗粒分布于肝细胞核或胞浆内,以单个或数个阳性细胞散布于肝小叶中。23例HCVRNA或/和HCAg-NS3阳性病例以肝炎后肝硬化(LC)病例占多数(14/23),其次为慢性重型肝炎(CSH)和中度慢性肝炎(CAH)。此两种检测方法具有较高符合率(90.4%,47/52),表明病毒核酸及其表达产物均存在于肝细胞内,与HCV感染密切相关。这为HCV感染诊断提供了直接依据,有利于研究HCV感染中病毒复制、慢性化进程、抗病毒治疗监测及重叠感染时病毒相互关系。 相似文献
1000.