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排序方式: 共有739条查询结果,搜索用时 484 毫秒
1.
Dr. Barry Pass John E. Aldrich Patricia L. Scallion 《Calcified tissue international》1990,46(3):166-168
Summary The ESR spectra produced in irradiated dentin have been studied over a range of incident radiation energies from 50 kVp to
25 MVp. The behavior of the dentin ESR signal strength is similar to that of enamel as a function of the energy of the incident
radiation. The magnitude of the dentin ESR signals are, however, up to 10 times smaller than the signals of dental enamel
for a given radiation energy. The possible contributions of radiation interaction coefficients, chemical structure, and crystallite
size to the differences in ESR spectra are discussed. 相似文献
2.
3.
本文报道1000例正常人发自由基的电子自旋共振波谱饱和功率(ESR-SP)的检测结果。所得正常值的全组中位数为2.496mw;95%上下限分别为2.989及1.720mw。如按性别统计,则女性下限(1.617mw)较男性(1.983mw)为低,(P<0.05)。按年龄分别统计,则40岁以上的中位数(2.376mw)及其下限(2.009mw)高于40岁以下的中位数(2.548mw)及其下限(1.597mw),两者差异有显著性(P<0.05)及极显著性(P<0.01)。因此在使用此正常值指标时,必须注意性别与年龄因素。 相似文献
4.
Clinical significance of a highly sensitive enzyme immunoassay of hepatitis B surface antigen using a novel electron spin resonance technique. 总被引:3,自引:0,他引:3
Masanori Aoki Takafumi Saito Hisayoshi Watanabe Taku Matsuo Koji Saito Hitoshi Togashi Sumio Kawata Kazuyoshi Ishikawa Masaaki Aoyama Hitoshi Kamada Haruhide Shinzawa 《Journal of medical virology》2002,66(2):166-170
We developed a highly sensitive enzyme immunoassay (EIA), the p-AP/HHTIO method, that detects serum hepatitis B surface antigen (HBsAg) by measuring stabilized nitroxide radicals using a novel electron spin resonance technique [Matsuo et al. (1998) Free Radic Biol Med 25:929-935]. To demonstrate the clinical significance of this method and to reveal occult hepatitis B virus (HBV) infection in patients, we used the method to analyze serum samples of 30 patients with acute or fulminant hepatitis who were negative for HBsAg by standard EIA, and those of seven chronic HBV carriers who became negative for HBsAg during a follow-up period by standard EIA. We also examined serum HBV DNA by amplification of the HBV S gene, using the polymerase chain reaction (PCR) technique. The p-AP/HHTIO method showed that 9 of 20 (45%) patients with acute hepatitis and 2 of 10 (20%) with fulminant hepatitis were positive for HBsAg; PCR detected HBV DNA in these HBsAg-positive patients. Antibody against hepatitis B core antigen was detected in one patient with fulminant hepatitis. The p-AP/HHTIO method demonstrated prolonged seropositivity of HBsAg even after standard EIA showed a loss of HBsAg in all seven HBV carriers. Our p-AP/HHTIO method is useful for screening and diagnosing HBV infection in patients with liver diseases who are negative for conventional HBV-related serological markers. 相似文献
5.
Zhang Y Siebert R Matthiesen P Harder S Theile M Scherneck S Schlegelberger B 《Virchows Archiv : an international journal of pathology》2000,436(3):271-275
For the first time, combined immunophenotyping and fluorescence in situ hybridization (FISH) technique according to the ”fluorescence
immunophenotyping and interphase cytogenetics as a tool for investigation of neoplasms” (FICTION) technique have been successfully
applied in solid tumors. Thus, we were able to visualize the antigen expression of cells with chromosomal deletions of a tumor
suppressor region directly. In six breast carcinoma cell lines, we investigated the correlation between estrogen receptor
(ER) expression status and deletions of the estrogen receptor gene (ESR). To screen for deletions of the ESR gene, dual-color
FISH was performed with a YAC (yeast artificial chromosome) probe containing the ESR gene and, as internal control, with a
centromeric probe of chromosome 6. Deletions of the ESR gene were detected in four of six cell lines. For direct comparison
of ER expression with the copy number of the ESR gene at the single cell level, immunophenotyping with mouse anti-human ER
antibody was combined with FISH with the YAC probe containing the ESR gene according to the FICTION technique. There was no
correlation between lack of or reduced ER expression and deletions of the ESR gene. One cell line with deletions of the ESR
gene did express ER on the protein level, while another cell line without a deletion did not. Cells with deletions of the
ESR gene were either ER expression positive or negative. The staining intensity of ER expression was not associated with the
copy number of the ESR gene. Thus, this FICTION study unequivocally shows that deletions of the ESR gene are not the major
cause of absent or reduced ER expression in breast carcinoma cell lines.
Received: 6 September 1999 / Accepted: 14 September 1999 相似文献
6.
中国健康人两项血液流变学参考值与海拔高度的关系 总被引:1,自引:0,他引:1
为制定中国健康成年男性血沉参考值(温氏法)和中老年女性红细胞压积参考值(温氏法)的统一标准提供科学依据,本文研究了中国226个单位测定的22707例健康成年男性的血沉参考值(温氏法)和312个单位测定的15608例健康中老年女性的红细胞压积参考值(温氏法),并对其与海拔高度的关系进行了研究,发现随着海拔高度的逐渐增大,健康成年男性血沉参考值(温氏法)在逐渐的减小,而健康中老年女性红细胞压积参考值(温氏法)在逐渐的增大,相关性都很显著。用回归分析的方法推导出了二个一元回归方程。如果知道了中国某地的海拔高度,就可以用这二个回归方程,估算这个地区的健康成年男性血沉参考值(温氏法)和健康中老年女性红细胞压积参考值(温氏法)。 相似文献
7.
David R. Allred Charles R. Sterling Philip D. Morse 《Molecular and biochemical parasitology》1983,7(1):27-39
The fluidity of Plasmodium berghei-infected mouse red cell membranes is increased over that of uninfected cells at both 24°C and 37°C. This was demonstrated by electron spin resonance spectroscopy using the hydrocarbon spin labels 2-dodecyl-2′,5,5′-trimethyloxazolidine-N-oxyl and 2-heptyl-2′ -hexyl-5,5′-dimethyloxazolidine-N-oxyl to label regions of the bilayer near its surface, and deeper within the hydrocarbon region, respectively. Arrhenius plots of the ‘empirical motion parameter’ (Ri) obtained from 2-heptyl-2′-hexyl-5,5′-dimethyloxazolidine-N-oxyl-labeled cells versus temperature over the range from 0 to 45°C showed an hysteretic behavior of the spin labels in the membranes of both mature and immature uninfected cells. Such hysteretic behavior was consistently lacking in membranes of infected cells. These differences in membrane fluidity and spin label behavior are interpreted to reflect biochemical modifications of the red cell membrane which occur with infection by the malarial parasite. 相似文献
8.
G L Sussman R P Harvey A L Schocket 《The Journal of allergy and clinical immunology》1982,70(5):337-342
Delayed pressure urticaria (DPU) is a poorly understood syndrome. We describe 17 patients with DPU. Chronic urticaria was present in 94%. All had negative challenges for immediate demographism and cold urticaria. DPU was induced with a pressure challenge on the shoulder of 15 pounds for 15 min. Average onset of pressure lesions after challenge was 6.5. Lesions were painful, not pruritic, peaked at 9 hr, and disappeared by 24 to 48 hr. Fever, chills, and/or arthralgias occurred in 78%. Positive laboratory abnormalities included leukocytosis in 20% and elevated erythrocyte sedimentation rate in 37.5%. Skin biopsies of lesions showed perivascular round cell infiltrates and negative immunofluorescence. Urticaria responded to antihistamines, but not aspirin, in 100% of patients, while pressure lesions improved with nonsteroidal anti-inflammatory drugs (NSAID), but not antihistamines, in 80% of patients. Both urticaria and DPU were controlled with prednisone, which was necessary in 87.5% of patients. A severe nonremitting course was noted in 7%, 40% had a moderate remitting course requiring intermittent prednisone, and 53% had a mild remitting disease requiring no medication or antihistamines and/or NSAID only. We conclude that DPU is more common than previously appreciated and likely involves mediators other than histamine, possibly the prostaglandin system. 相似文献
9.
Kayoko Minakata Osamu Suzuki Takeshi Kumazawa Minoru Asano Naoko Harada 《International journal of legal medicine》1990,103(8):599-607
Summary An electron spin resonance (ESR) method already in use for the quantitative analysis of paraquat was applied to the analysis of diquat in blood, serum, urine, tissue homogenates and several drinks without purification of the samples. The diquat radical produced with ascorbic acid at alkaline pH was much more stable than that produced with the commonly used sodium dithionite. Radical decay in solutions covered with n-hexane was less than 5% after 60 min over a wide range of ascorbic acid concentrations. In 0.2N NaOH solution 85% of the radicals was present even after 24h. The limit of detection was 0.3 g/ml and the required amount of sample was 0.1 ml. When both diquat and paraquat were present in a sample the diquat was first extracted with 1-butanol prior to the ESR measurement, because both species were converted to the radicals. 相似文献
10.
合成N,N,N′,N′ 四 [2 (2 吡啶基)乙基]丁二酰胺(SDP)双核铜(Ⅱ)配合物,并用红外光谱(IR)、电子光谱、电导和元素分析进行表征。3种配合物的电子自旋共振谱(ESR)表明g∥>g⊥,故均为典型Cu(Ⅱ)四方配位。在DMF溶液中,用循环伏安法研究了配合物的电化学性质,3种配合物均为2步1电子准可逆电子转移过程。 相似文献