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排序方式: 共有2745条查询结果,搜索用时 15 毫秒
21.
A Serda Kantarcio?lu Teun Boekhout G Sybren De Hoog Bart Theelen Ayhan Yücel Tuba R Ekmekci Bettina C Fries Reiko Ikeda Adem Koslu Kemal Altas 《Medical mycology》2007,45(2):173-181
Environmental fungi, in particular primary pathogens and Cryptococcus spp. can be responsible for skin lesions mimicking sporotrichosis. In this paper, we report a case of subcutaneous cryptococcosis in an apparently healthy, young male patient due to a non-C. neoformans Cryptococcus species, C. diffluens. The isolate showed in vitro phenotypic switching that may affect virulence and host inflammatory and immune responses, and in vitro resistance to amphotericin B and 5-flucytosin. This species shares several phenotypic traits with C. neoformans, and, therefore, decisive diagnosis should be based on biopsy and culturing results followed by molecular identification. 相似文献
22.
The 44-amino-acid E5 oncoprotein of bovine papillomavirus type 1 transforms immortalized murine fibroblast cell lines. This highly hydrophobic protein forms homodimers, localizes to intracellular membrane compartments (including the Golgi apparatus), and forms a complex with the 16-kDa membrane-embedded constituent (16k) of the vacuolar proton-ATPase. To develop a system for the genetic and biochemical analysis of the E5/16k interaction, the E5 gene was cloned into a new vector which was designed for expression in the fission yeast Schizosaccharomyces pombe. The E5 protein synthesized in this system dimerized normally and bound to endogenous and overexpressed S. pombe 16k protein. Comparison of the S. pombe and mammalian 16k proteins showed strong conservation in carboxyl-terminal amino acids but greater variation in the amino-terminal sequences, suggesting that E5 was interacting with the 16k carboxyl domains. Finally, a new protein epitope tag is described which permitted for the first time the coprecipitation of E5 with antibodies directed against the 16k protein. 相似文献
23.
24.
Electrical polarization of plasma-spray-hydroxyapatite coatings for improvement of osteoconduction of implants 总被引:1,自引:0,他引:1
Kato R Nakamura S Katayama K Yamashita K 《Journal of biomedical materials research. Part A》2005,74(4):652-658
We have established the electrical polarization method of hydroxyapatite (HA) coatings (HAC) for clinical use, such as dental and orthopedic implants. The HAC examined in the current study was prepared in titanium substrates by plasma spraying of beta-tricalcium phosphate (TCP) powders followed by hydrothermal treatment. The prepared HAC consisted of a single phase of HA, because the starting TCP phase was completely transformed to the HA phase during the posthydrothermal treatment. Polarization was carried out at the elevated temperature of 400 degrees C under a d.c. field of 1 kV . cm(-1). The electrical measurements showed that the stored charges of the polarized HAC were greater than the reported value of the sintered ceramic HA. The enhanced bioactivity of the polarized HAC was demonstrated using 1.5 simulated body fluid (SBF). The crystal growth from the SBF solution was accelerated on the negatively charged surface in comparison with the untreated HAC. Similar to the polarized ceramic HA, the current results confirmed that the bioactivity of HAC would be effective for improving the initial fixation by polarization. 相似文献
25.
Kayo Adachi Michihiko Momota Yoshiki Teranishi Reiko Ueki Masatoshi Hagiwara Takashi Wakabayashi Jerzy Popinigis 《Pathology international》1992,42(8):549-557
The physicochemical properties of mitochondria in liver tissue obtained from rats given 32% ethanol, 32% propanol or 6.9% butanol in drinking water for up to 3 months were investigated using differential scanning calo-rimetry and fluorescence polarization measurements. The results obtained were as follows: 1) Phospholipids extracted from mitochondria showed increases in the relative amounts of phosphatidylcholine, phosphatidylinositol and phosphatidylserine, and a decrease in the relative amount of phosphatidylethanolamine. An increase in the unsatu-rated/saturated fatty acid ratio of phospholipids was also observed. 2) Elevation of the thermotropic lipid phase transition temperature with a decrease in the enthalpy value (δ H ) was revealed by differential scanning calo-rimetry. 3) The elevation of the lipid phase transition temperature was detected also by fluorescence polarization measurements using 1,6 diphenyl 1, 3, 5 hexatriene (DPH) as a probe. Elevation of mitochondrial membrane fluidity was found in some of the experimental animals, but most showed no changes in comparison with the control. A possible role of membrane fusion in the mechanism of formation of ethanol-, propanol- and butanol induced hepatic megamitochondria is discussed on the basis of these results. Acta Pathol Jpn 42: 549–557, 1992. 相似文献
26.
Fujimoto Y Okuyama T Iijima M Tanaka T Horikawa R Yamada K Ogata T 《Molecular genetics and metabolism》2004,82(2):173-179
Although testicular development has been shown to be variably impaired in XY patients with distal 9p monosomy, ovarian and other genitourinary phenotype has poorly been studied in XX patients monosomic for the distal 9p region. Thus, we studied a 13-month-old infant with 46,XX,der(9)t(9;10)(p23;p13) (case 1) and an 11-year-old girl with 46,XX,der(9)t(9;16)(p23;q22) (case 2). Case 1 had primary hypogonadism (basal serum follicle stimulating hormone [FSH], 40.0 mIU/mL; leteinizing hormone [LH], 1.2 mIU/mL; estradiol [E2], <10 pg/mL), whereas case 2 had age-appropriate pubertal development (breast, Tanner stage 4; pubic hair, Tanner stage 3; menarche 11.7 years of age) and hormone values (FSH, 7.3 mIU/mL; LH, 6.7 mIU/mL; E2, 47 pg/mL). In addition, case 1 had hypoplastic labia majora, short distance between the vaginal orifice and the anus, and five renal cysts, and case 2 had anal atresia, short distance between the vaginal orifice and the anus, bilateral hydronephrosis of grade 3 with probable ureteropelvic junction stenosis, and renal dysfunction (serum creatinine, 1.52 mg/dL; urea nitrogen, 34.5mg/dL). Fluorescence in situ hybridization analysis for five regions and microsatellite analysis for 10 loci on 9p confirmed hemizygosity for the distal 9p region with the breakpoints between IFNA and D9S285 in case 1 and between D9S168 and D9S286 in case 2. The results, in conjunction with the previous data in XX patients with molecularly defined distal 9p monosomy, are consistent with the presence of a gene(s) involved in the development of indifferent gonad or subsequent ovarian differentiation in a approximately 11 Mb region distal to D9S168. In addition, it is possible that a gene(s) for anoperineal and renal development also maps distal to D9S168 and that for external genital development maps distal to D9S285 at the position approximately 16 Mb from the 9p telomere. 相似文献
27.
Tsuneyoshi H Oriyanhan W Kanemitsu H Shiina R Nishina T Ikeda T Nishimura K Komeda M 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2005,51(1):116-120
The left ventricular assist device (LVAD) is usually used in patients with end-stage heart failure as a bridge to transplantation. Recently, some studies have reported functional recovery with the use of an LVAD, although the mechanisms responsible for recovery are not fully understood. We investigated the functional recovery of the infarcted, failing rat heart in response to mechanical unloading after heterotopic transplantation. Heart failure was induced in Lewis rats by ligating the left anterior descending artery. After 4 weeks, the infarcted hearts were harvested and heterotopically transplanted. The transplanted infarcted heart was removed after 2 weeks of unloading and examined for hypertrophy and fibrosis, as well as for mRNA levels encoding for brain natriuretic peptide, sarco(endo)plasmic reticulum Ca(2+)-ATPase2a (SERCA2a), and beta1- and beta2-adrenergic receptors. Normal and infarcted rats without transplantation served as control animals. The infarcted heart was hypertrophied as evidenced by an increase in heart weight and myocyte diameter. After unloading the infarcted heart for 2 weeks, there was a decrease in heart weight and myocyte diameter. However, the percentage of myocardial fibrosis increased after unloading. The mRNA expression of brain natriuretic peptide and the beta2-adrenergic receptor significantly improved after mechanical unloading. The levels of SERCA2a mRNA tended to increase after unloading. In conclusion, unloading the failing, infarcted heart can help normalize left ventricular hypertrophy and cardiac gene expression. This unloading model appears to partially mimic the conditions of hemodynamic support with an LVAD in heart failure patients and potentially offers insights into the mechanisms of functional recovery. 相似文献
28.
Reiko Yoshida Yoshimitsu Fukushima Hirofumi Ohashi Masako Asoh Yukio Fukuyama 《Journal of human genetics》1993,38(4):437-444
Summary Two patients with the Costello syndrome are presented. One was a 7-year-old girl with a history of infantile hypotonia and feeding difficulties. The other was a 3 5/12-year-old boy with a history of neonatal sepsis and respiratory problems. Both had relative macrocephaly at birth, curly hair, large ear lobes, epicanthic folds, a low nasal bridge, thick lips, a short and wide nose, a short neck, a barrel chest, redundant skin, tight Achilles tendons, and pes equinovarus. Nasal papillomata, as described in Costello's two patients, were absent in both patients. Borochowitzet al. (1992) described five patients with what we interpreted as the Costello syndrome but without nasal papillomata. In view of these findings, nasal papillomata are not likely to be essential in the diagnosis of the Costello syndrome. 相似文献
29.
Clinicopathological significant and prognostic influence of cadherin-17 expression in gastric cancer 总被引:5,自引:0,他引:5
Ito R Oue N Yoshida K Kunimitsu K Nakayama H Nakachi K Yasui W 《Virchows Archiv : an international journal of pathology》2005,447(4):717-722
Cadherin-17 (CDH17), also called liver–intestine cadherin, is a structurally unique member of the cadherin superfamily. Our
serial analysis of gene expression demonstrated that CDH17 was one of the most up-regulated genes in advanced gastric carcinomas.
CDH17 expression is known to be regulated by Cdx2. In the present study, we examined the expression of CDH17 in primary gastric
carcinoma tissues by immunohistochemistry, and analyzed the correlation of CDH17 expression with clinicopathological characteristics
and patients prognosis. CDH17 expression was detected in 63/94 (67%) of gastric adenocarcinomas in addition to intestinal
metaplasia. The expression of CDH17 tended to be associated with intestinal type carcinoma, and carcinomas with CDH17 expression
was significantly more frequent in advanced stage cases (80%) than in early stage (53%). The prognosis of patients with positive
CDH17 expression was significantly poorer than that of the negative cases (P=0.0314). However, multivariate analysis revealed that CDH17 was not an independent prognostic factor. Six of seven cases
that showed positive expression of Cdx2 simultaneously expressed CDH17 protein. These results suggested that the expression
of CDH17 was characteristic of the advanced gastric carcinoma that is associated with poor prognosis. 相似文献
30.
Yamada H Shimada S Morikawa M Iwabuchi K Kishi R Onoé K Minakami H 《Molecular human reproduction》2005,11(6):451-457
The aim of this cohort study was to investigate immunophenotypic characteristics of natural killer (NK) cells by assessing specific molecules expressed in the decidua of sporadic miscarriages and induced abortions. The deciduae were obtained from 29 consecutively seen women whose pregnancies ended in first trimester miscarriages (MS), and the fetal chromosome karyotype of these MS was analysed. Additionally, 13 deciduae were obtained from induced abortion (IA) with informed consent. The expression of perforin, CD94, CD161, CD158a, CD158b, CD244 on CD3-CD56+NK cells, and perforin on CD3+CD8+ T cells was analysed by flow cytometry. The CD158a (mean+/-SD, 26.2+/-14.7%) and CD94 (50.2+/-25.7%) expressions in MS with normal chromosome karyotype (MSNK; n=11) were significantly decreased as compared with those (41.5+/-19.5%, 71.4+/-20.4%) in MS with abnormal karyotype (MSAK; n=18) and those (44.3+/-21.9%, 80.8+/-17.5%) in IA (n=13). Conversely, the perforin expression on CD3-CD8-CD56+NK cells (76.3+/-11.0%) and CD3+CD8+T cells (30.6+/-9.2%) in MSNK was significantly increased as compared with those (66.8+/-16.6%, 23.6+/-8.7%) in MSAK and those (62.9+/-11.6%, 19.7+/-8.1%) in IA. A positive correlation between CD94 and CD158a expressions on NK cells, negative correlations between CD94 on NK cells and perforin on NK cells/T cells, and between CD158a on NK cells and perforin on T cells were found in the decidua. A divergence of NK cell repertoire in the decidua might be related to aetiology of sporadic MSNK. 相似文献