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排序方式: 共有7130条查询结果,搜索用时 15 毫秒
91.
K Nishikawa T Morii H Ako K Hamada S Saito N Narita 《The Journal of allergy and clinical immunology》1992,90(2):169-174
The antigen, CD69, has been demonstrated to be expressed on activated T cells and natural killer cells. There have been no studies concerning the expression of CD69 on eosinophils. In this article, we demonstrate that lung eosinophils obtained from the bronchoalveolar lavage fluid of patients with eosinophilic pneumonia expressed significant levels of CD69, whereas peripheral blood (PB) eosinophils did not express CD69. We also activated PB eosinophils in vitro using phorbol myristate acetate and cytokines to determine whether CD69 was expressed. PB eosinophils expressed CD69 after short-term culture with phorbol myristate acetate and eosinophil hemopoietic cytokines (interleukin-3, granulocyte-macrophage--colony-stimulating factor, and interleukin-5). These findings suggest that CD69 may be a useful marker for activated eosinophils at inflammatory sites. 相似文献
92.
S Shimano M Fukushima T Yamaguti Y Yamakawa A Nishikawa S Takashima K Tukamoto H Narimatu K Fujinaga M Hashimoto 《Rinsho byori. The Japanese journal of clinical pathology》1990,38(11):1291-1294
We studied a sensitivity of HPV DNA detection by in situ hybridization method using 3H labeled HPV DNA. The materials were CaSki cells and SiHa cells which were derived from as a negative control. The total cellular DNAs extracted from these cell lines were estimated copy numbers of HPV 16 DNA using Southern blot hybridization. In our result, CaSki cell has 400 copies/cell, SiHa cell were appeared to have 1-5 copies/cell. Simultaneously these cells were fixed by periodate-buffered lysine-paraformaldehyde-glutaraldehyde (PLPG) and were detected HPV 16 DNA using in situ hybridization. We detected HPV 16 DNA in CaSki cells and SiHa cells by in situ hybridization also. We concluded that the sensitivity of our in situ hybridization technique is 1-5 copies/cell. 相似文献
93.
Yohtaro Numachi Sumiko Yoshida Motoyasu Yamashita Ko Fujiyama Shigenobu Toda Hiroo Matsuoka Yasushi Kajii Toru Nishikawa 《Neuroscience letters》2007
Methamphetamine is a potent and indirect dopaminergic agonist which can cause chronic brain dysfunctions including drug abuse, drug dependence and drug-induced psychosis. Methamphetamine is known to trigger molecular mechanisms involved in associative learning and memory, and thereby alter patterns of synaptic connectivity. The persistent risk of relapse in methamphetamine abuse, dependence and psychosis may be caused by such alterations in synaptic connectivity. EphA5 receptors constitute large families of tyrosine kinase receptor and are expressed almost exclusively in the nervous system, especially in the limbic structures. Recent studies suggest EphA5 to be important in the topographic projection, development, and plasticity of limbic structures, and to be involved in dopaminergic neurotransmission. We used in situ hybridization to examine whether methamphetamine alters EphA5 mRNA expression in the brains of adult male Wister rats. EphA5 mRNA was widely distributed in the medial frontal cortex, cingulate cortex, piriform cortex, hippocampus, habenular nucleus and amygdala. Compared to baseline expression at 0 h, EphA5 mRNA was significantly decreased (by 20%) in the medial frontal cortex at 24 h, significantly increased (by 30%) in the amygdala at 9 and 24 h, significantly but transiently decreased (by 30%) in the habenular nucleus at 1 h after a single injection of methamphetamine. Methamphetamine did not change EphA5 mRNA expression in the cingulate cortex, piriform cortex or hippocampus. Our results that methamphetamine altered EphA5 mRNA expression in rat brain suggest methamphetamine could affect patterns of synaptic connectivity, which might be responsible for methamphetamine-induced chronic brain dysfunctions. 相似文献
94.
Antifungal activities of tacrolimus and azole agents against the eleven currently accepted Malassezia species 总被引:5,自引:0,他引:5
Sugita T Tajima M Ito T Saito M Tsuboi R Nishikawa A 《Journal of clinical microbiology》2005,43(6):2824-2829
The lipophilic yeast Malassezia is an exacerbating factor in atopic dermatitis (AD) and colonizes the skin surface of patients with AD. With the goal of reducing the number of Malassezia cells, we investigated the antifungal activities of a therapeutic agent for AD, tacrolimus, and the azole agents itraconazole and ketoconazole against Malassezia species in vitro. We examined 125 strains of the 11 currently accepted Malassezia species by using the agar dilution method. All strains of the 11 Malassezia species were very susceptible to both azole agents, with MICs ranging from 0.016 to 0.25 mug/ml. Tacrolimus had antifungal activities against half of the strains, with MICs ranging from 16 to 32 mug/ml. Two of the major cutaneous floras, Malassezia globosa and Malassezia restricta, have several genotypes in the intergenic spacer region of the rRNA gene; the azole agents had slightly higher MICs for specific genotype strains of both microorganisms. A combination of azole agents and tacrolimus had a synergistic effect against Malassezia isolates, based on a fractional inhibitory index of 0.245 to 0.378. Our results provide the basis for testing these agents in future clinical trials to reduce the number of Malassezia cells colonizing the skin surface in patients with AD. 相似文献
95.
Michio Tanaka Shutaro Satake Yutaka Kawahara Masaya Sugiura Kenzo Hirao Kazushi Tanaka Tokuhiro Kawara Akihiro Masuda Toshio Nishikawa Takeshi Kasajima 《Pathology international》1991,41(7):487-498
Radiofrequency catheter ablation of the atrioventricular (AV) node or bundle of His was performed in 12 adult mongrel dogs. The aim was to create chronic incomplete AV block (first- and second-degree AV block) and to examine the histopathology of the ablated lesions. However, the late electrophysiological results (2 4 weeks follow up) were various: normal in 2 dogs, mild PR prolongation (< 50%) in 2 dogs, first-degree AV block (PR prolongation a 50%) in 2 dogs, second degree AV block in 2 dogs, complete AV block in 4 dogs. The maximally ablated area (%) of the atrioventricular conduction system in serial histologic sections from dogs with these conditions was 69%, 75%, 89.5%, 95% and 99.5%, respectively. The number of intact conduction cells at the maximally ablated site varied from 6 to 30 in the four cases of incomplete AV block. The mean ablated volume (%) of either the AV node or penetrating His bundle correlated roughly with the degree of AV block. The ablated lesions were well demarcated and almost replaced by dense fibrous tissue at 4 weeks. Interruption (3 dogs) or thinning (1 dog) of the endocardial elastic lamellae was detected, in association with endocardial thickening (mean 913 μm). Endocardial thrombi were found in 3 dogs (2 fresh, 1 organized). We conclude that radiofrequency catheter ablation does not cause severe complicated lesions. Several possible conditions for creating chronic incomplete AV block are discussed. Acta Pathol Jpn 41: 487–498, 1991. 相似文献
96.
Xuan Xuenan Nishikawa Yoshifumi Takashima Yasuhiro Tuchiya Kotaro Ueda Susumu Yokoyama Naoaki Maeda Ken Mikami Takeshi Otsuka Haruki 《Virus genes》1998,17(1):25-32
An improved method for constructing canine herpesvirus (CHV) recombinants expressing foreign genes by using the lacZ-TK gene
cassette as a double selectional marker was developed. A recombinant CHV carrying the lacZ-TK gene at a targeted gene locus
was constructed and used as a parental virus for generating new recombinants. The parental virus formed blue plaques and was
sensitive to TK-specific drugs, while newly generated recombinants, in which the lacZ-TK gene was replaced with the desired
foreign gene, become both resistant to the TK-specific drugs and formed white plaques. Recombinants were isolated by using
the combination of drug selection and color selection. This improved method allows construction of recombinant CHV with great
ease, because the drug selection can enrich the frequency of recombinant CHV from 0.01–0.1% to 10–80%. This method was employed
to construct a recombinant CHV that expressed rabies virus (RV) glycoprotein (G protein).
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
97.
The prevalence of TT virus (TTV) infection and its relationship to hepatitis in children 总被引:4,自引:0,他引:4
Iriyama M Kimura H Nishikawa K Yoshioka K Wakita T Nishimura N Shibata M Ozaki T Morishima T 《Medical microbiology and immunology》1999,188(2):83-89
TT virus (TTV) is a newly discovered virus from a patient with post-transfusion hepatitis. We investigated the frequency
and pathogenesis of TTV infection in children. A semi-nested PCR assay was used to amplify TTV-DNA in serum samples from 254
ambulatory children without liver disease, 20 with hepatitis of unknown etiology, and 18 transfusion recipients or hemophiliacs.
In positive samples, TTV-DNA was quantified by real-time quantitative PCR using a fluorescent probe. We detected TTV-DNA in
20% of children with hepatitis of unknown etiology, which was not statistically different from the 23% prevalence in ambulatory
children. In transfusion recipients or hemophiliacs, the frequency was higher (50%) than that in ambulatory children (P = 0.01). Among ambulatory children, TTV-DNA was frequently detected in children with acute gastroenteritis (36%). TTV-DNA
was detected in 10% of the infants under 6 months old, and 20% of the children from 7 to 12 months old. The prevalence was
constant after the age of 1 year; however, the copy number of TTV-DNA was significantly higher in children under 1 year of
age (mean: 105.4 versus 103.8 copies/ml, P= 0.008). Finally, TTV-DNA was quantified serially in three children with chronic hepatitis who were positive for TTV-DNA.
The presence or amount of TTV-DNA was unrelated to the serum alanine aminotransferase level. These results indicate that TTV
infection is common in children. The larger quantity of TTV-DNA in infants and the high prevalence of TTV in children of all
ages suggest that TTV may be transmitted in early childhood. Its relationship to hepatitis is doubtful in children.
Received: 8 April 1999 相似文献
98.
Follicular density in ovarian biopsy of infertile women: a novel method to assess ovarian reserve 总被引:4,自引:15,他引:4
Lass A; Silye R; Abrams DC; Krausz T; Hovatta O; Margara R; Winston RM 《Human reproduction (Oxford, England)》1997,12(5):1028-1031
The ageing ovary appears to be characterized by depletion of primordial
follicles. The relationship between infertility and the number of follicles
in the ovarian cortex is not known. Moreover, there are no accurate markers
or clinical methods to predict the decline in ovarian reserve. This study
investigates the correlation between early follicular follicle stimulating
hormone, ovarian size and follicular density in 60 infertile women aged
19-45 years (mean = 34.4 +/- 5.5). An ovarian biopsy was taken from each
patient while performing diagnostic laparoscopy (n = 28) or laparotomy for
tubal surgery or myomectomy (n = 32). The median number of follicles was
similar in tubal and unexplained infertility patients (9.5 versus 5.5).
Increasing age showed a significant negative correlation with follicular
density and ovarian volume (r = -0.46, P = 0.0003;. r = -0.43, P = 0.0016,
respectively). In women > or = 35 years of age the ovarian volume showed
a strong correlation with follicular density (r = 0.71, P < 0.0001). Our
results indicate that infertile women in their late thirties and over have
a decreased ovarian reserve which could possibly be predicted by ovarian
volume measurement. Ovarian biopsy may have a place as part of infertility
evaluation in older women.
相似文献
99.
Computerized detection of clustered microcalcifications in digital mammograms: applications of artificial neural networks. 总被引:3,自引:0,他引:3
Artificial neural networks have been applied to the differentiation of actual "true" clusters from normal parenchymal patterns and also to the differentiation of actual clusters from false-positive clusters as reported by a computerized scheme for the detection of microcalcifications in digital mammograms. The differentiation was carried out in both the spatial and frequency domains. The performance of the neural networks was evaluated quantitatively by means of receiver operating characteristic (ROC) analysis. It was found that the networks could distinguish clustered microcalcifications from normal nonclustered areas in the frequency domain, and that they could eliminate approximately 50% of false-positive clusters of microcalcifications while preserving 95% of the positive clusters, when applied to the results of the automated detection scheme. A large, comprehensive training database is needed for neural networks to perform reliably in clinical situations. 相似文献
100.
A new pseudo-peptide of Arg-Gly-Asp (RGD) with inhibitory effect on tumor metastasis and enzymatic degradation of extracellular matrix 总被引:2,自引:0,他引:2
Hideki Fujii Naoyuki Nishikawa Hiroyuki Komazawa Makoto Suzuki Masayoshi Kojima Isamu Itoh Aya Obata Koichi Ayukawa Ichiro Azuma Ikuo Saiki 《Clinical & experimental metastasis》1998,16(1):94-104
A series of pseudo-peptide analogs of the Arg-Gly-Asp (RGD) sequence of fibronectin have been synthe-sized, and their anti-metastatic effects in mice and inhibitory effects on tumor cell invasion in vitro have been examined. The partially modified retro pseudo-peptide of RGD, Rrev-COCH2CO-D (FC-63), was more effective in inhibiting tumor metastasis than the original RGDS peptide. Replacement of the malonyl moiety of FC-63 with a carboxyethylene linkage (Rrev-COCH2CH2-D, FC-303 ) achieved more potent inhibition of lung metastasis of melanoma cells than FC-63. Among the analogs, FC-336, a p-xylylendiamine derivative having two FC-303 moieties, showed the most potent inhibitory effect on experimental lung metastasis produced by i.v. co-injection with B16-BL6 melanoma or colon 26 M3.1 cells in a dose-dependent manner. Multiple administrations of FC-336 after tumor inoculation also showed efficient therapeutic potency against spontaneous lung metastasis of B16-BL6 melanoma in mice. Furthermore, FC-336 effectively inhibited the invasion, migration and adhesion of tumor cells in vitro, but its inhibitory effects were not more than those of RGDS peptide. Zymography analysis revealed that FC-336 inhibited the degradation of gelatin substrate by matrix metalloproteinases (MMPs) produced by tumor cells, while the RGDS peptide did not affect the enzymatic degradation. These findings indicate that the pseudo-peptides of the RGD sequence, possessing the inhibitory property of the degradation by MMPs differently from original RGD-containing peptides, may be advantageous and useful in preventing tumor metastasis. © Rapid Science 1998 相似文献