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排序方式: 共有466条查询结果,搜索用时 343 毫秒
1.
Keiichiro Yoshinaga Chietsugu Katoh Kazuyuki Noriyasu Yasuyoshi Iwado Hideto Furuyama Yoshinori Ito Yuji Kuge Tetsuro Kohya Akira Kitabatake Nagara Tamaki 《Journal of nuclear cardiology》2003,10(3):275-283
BACKGROUND: Myocardial perfusion single photon emission computed tomography (SPECT) occasionally fails to detect coronary stenosis in patients with coronary artery disease (CAD). We evaluated coronary flow reserve (CFR) using oxygen 15-labeled water in areas with and without ischemia on technetium 99m tetrofosmin stress perfusion SPECT in patients with angiographically documented CAD. METHODS AND RESULTS: Twenty-seven patients with CAD and eleven age-matched normal subjects were studied. Baseline myocardial blood flow (MBF) and MBF during hyperemia induced by intravenous adenosine triphosphate infusion (0.16 mg. kg(-1). min(-1)) were determined with the use of O-15-labeled water positron emission tomography, and the CFR was calculated. Tc-99m tetrofosmin stress/rest SPECT was performed for comparison. On the basis of the results of coronary angiography and SPECT, coronary segments were divided into 3 types: segments with coronary stenosis and a perfusion abnormality on stress SPECT imaging (group A, n = 16), segments with coronary stenosis without a perfusion abnormality (group B, n = 42), and remote segments with no coronary stenosis or perfusion abnormality (group C, n = 18). Baseline MBF values were similar among the 3 groups. CFR in group A was lower (1.82 +/- 0.54) than in group B (2.22 +/- 0.87, P <.05), in group C (2.92 +/- 1.21, P <.01), and in normal segments (3.86 +/- 1.24, P <.001). CFR in group B was lower than in group C (P <.02) and in normal segments (P <.001). CFR in group C was lower than in normal segments (P <.02). CONCLUSIONS: Areas with a perfusion abnormality on stress SPECT had reduced CFR. In the areas without a perfusion abnormality and with coronary stenosis, lowering of CFR was intermediate between the areas with a perfusion abnormality and remote segments. Moreover, CFR was slightly, but significantly, lower in remote segments in patients with CAD compared with normal segments. 相似文献
2.
Kazuo Tamura Yoshihiro Yamamoto Yoshifumi Saeki Jun-ichi Furuyama Joji Utsunomiya 《Human mutation》1993,2(6):478-484
Germline mutations in patients with familial adenomatous polyposis were analyzed by polymerase chain reaction (PCR) amplification of the adenomatous polyposis coli gene. PCR products from heterozygous patients for deletions of this gene formed four distinct bands on polyacrylamide gel electrophoresis. The four fragments were subsequently purified and both strands of each fragment were directly sequenced, using an automated DNA sequencer and the same primers as those for PCR amplification. It was found that the two slower migrating fragments were “bulge” heteroduplexes, while the other two were homoduplexes made up of two wild-type strands and two deletion-mutant strands, respectively. The sites of deletions in the adenomatous polyposis coli gene could be exactly determined in four of the five patients. In an attempt to identify deletion-carriers of familial adenomatous polyposis at the presymptomatic stage, a family study was also carried out, and two children were found to have the same mutations as those of their affected parents. The direct sequencing of heteroduplex fragments generated during PCR amplification is a potentially useful method for detecting mutations of not only the adenomatous polyposis coli gene but also many other genes of genetic diseases. © 1993 Wiley-Liss, Inc. 相似文献
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4.
Characterization and expression of cDNA encoding coproporphyrinogen oxidase from a patient with hereditary coproporphyria 总被引:2,自引:1,他引:2
Fujita Hiroyoshi; Kondo Masao; Taketani Shigeru; Nomura Nakao; Furuyama Kazumichi; Akagi Relko; Nagai Tadashi; Terajima Masanori; Galbraith Richard A.; Sassa Shigeru 《Human molecular genetics》1994,3(10):1807-1810
Hereditary coproporphyria (HCP) is an acute hepatic porphyriawith autosomal dominant inheritance, but with a variable degreeof clinical expression. Molecular cloning, sequencing and expressionof the defective gene for coproporphyrinogen oxidase (CPO) ina patient with HCP were carried out. Enzyme assays revealedthat CPO activity in EBV-transformed lymphoblastoid cells fromthe proband and one of her sisters was 相似文献
5.
Plaque assay and primary isolation of influenza a viruses in an established line of canine kidney cells (MDCK) in the presence of trypsin 总被引:43,自引:0,他引:43
A wide variety of influenza A viruses, comprising human, equine, porcine, and avian strains, grew productively in an established line of canine kidney cells (MDCK) under an overlay medium containing trypsin, and formed well-defined plaques regardless of their prior passage history. Plaquing efficiency was comparable to the efficiency of infection in fertile eggs via allantoic route. MDCK cells have also been successfully employed for the primary isolation of influenza A virus from throat washings of patients. Parallel titration of several clinical specimens showed that the inoculation into MDCK cells followed by incubation in the presence of trypsin was an isolation procedure as sensitive as the amniotic inoculation into fertile eggs. 相似文献
6.
The lower limits of the "therapeutic range" for serum levels of sodium valproate (VPA) were evaluated in epileptic children showing a benign clinical course. Twenty-five outpatients, aged 5 to 16 years, whose seizures were well controlled over three years with VPA alone, were studied. Venous blood was taken 1.1 to 5 hrs after the morning dose. Serum VPA concentrations at steady-state after receiving the maintenance doses to control seizures were determined by enzyme immunoassay. The patients were divided into three groups according to the seizure type and the age at onset; A and B: patients with tonic and/or clonic seizures, aged below 3 yrs (n = 11) and 3 to 11 yrs (n = 6), respectively, C: those with absence seizures, aged 4 to 11 yrs (n = 8). The serum concentrations in A (47.8 +/- 21.6 micrograms/ml, mean +/- SD) were significantly (p less than 0.02) lower than those in groups B and C (85.2 +/- 14.0 and 73.0 +/- 17.4 micrograms/ml, respectively). VPA concentrations below 50 micrograms/ml were seen in 6 patients (55%) in group A. It was concluded that many epileptic children, whose ages at onset were below 3 yrs, with tonic and/or clonic seizures could be controlled even with low initial serum concentrations below the "therapeutic range". 相似文献
7.
An isolated case of Duchenne muscular dystrophy (DMD) in a female who has a deletion of the DMD locus is described. This patient was a 26-year-old woman born to unrelated, healthy parents. She was initially examined at age 6 because of a waddling gait. At age 15, pseudohypertrophy of calves and pes equinus were observed along with proximal muscular weakness and wasting. Her serum creatine kinase level was high and histological evidence of muscular dystrophy was apparent on muscle biopsy. The patient was ambulant at age 15 and progression of motor disability has been slow. Chromosomal studies revealed a normal karyotype, and mental retardation is moderate. DNA analysis at age 26 revealed that she has a deletion of DMD cDNA 8 mapped within Xp21 and is heterozygous for the deletion. Since diagnosis of DMD is now dependent on the evidence of mutation or deletion at Xp21, this patient is thought to have a form of DMD. Expression of the DMD gene in the heterozygous state might be due to random but unequal lyonization. 相似文献
8.
Nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit experimental carcinogenesis and their use in humans has been related epidemiologically to a reduced risk of colorectal polyps and cancer, although the mechanism involved is not known. We found that aspirin triggered the death of SW948 human colorectal adenocarcinoma cells through activation of an apoptotic pathway. Exposure of SW480 and SW948 cells to 25 mu M aspirin for 5 h resulted in the detatchment of cells from the monolayer culture at 48 h. SW948 cells with continuous exposure to 25 mu M aspirin exhibited various morphological and biochemical characteristics of apoptosis, including compact patches of condensed nuclear chromatin, and DNA fragmentation. These in vitro data suggest that apoptosis may play a role in the antitumor effect of aspirin and other NSAIDs and that the induction of apoptosis may provide an attractive therapeutic target in colorectal carcinogenesis. 相似文献
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10.
Hiroyoshi Machida Yoko Shibata Sumito Inoue Akira Igarashi Yoshikane Tokairin Keiko Yamauchi Tomomi Kimura Kento Sato Hiroshi Nakano Michiko Nishiwaki Maki Kobayashi Sujeong Yang Yukihiro Minegishi Kodai Furuyama Tomoka Yamamoto Tetsu Watanabe Tsuneo Konta Yoshiyuki Ueno Isao Kubota 《Respiratory investigation》2018,56(1):34-39