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排序方式: 共有4609条查询结果,搜索用时 31 毫秒
31.
Molecular cloning and sequence analysis of antigen gene tdpA of Treponema denticola. 总被引:6,自引:4,他引:6
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![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
M Miyamoto S Noji S Kokeguchi K Kato H Kurihara Y Murayama S Taniguchi 《Infection and immunity》1991,59(6):1941-1947
We isolated and characterized an immunogenic protein of an oral spirochete, Treponema denticola Johnson. A genomic DNA library constructed with bacteriophage lambda EMBL3 as a vector was immunologically screened with a rabbit antiserum against the whole cells. Using Western immunoblot analysis, we found a particular clone encoding an antigen with a molecular weight of 53,000; we designated the antigen as T. denticola protein A (TdpA). Complete sequence determination revealed an open reading frame of 1,419 bp and a signal peptide sequence that was homologous to that of bacterial lipoprotein. Southern hybridization analysis revealed that the tdpA gene is highly conserved in six tested strains of T. denticola species. Furthermore, we found that sera from some periodontitis patients contained antibody against the TdpA protein, although the reactivities of the antibodies varied among individuals. 相似文献
32.
Fecal microflora in a patient with short-bowel syndrome and identification of dominant lactobacilli.
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![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
T Kaneko Y Bando H Kurihara K Satomi K Nonoyama N Matsuura 《Journal of clinical microbiology》1997,35(12):3181-3185
Fecal microflora and lactate concentrations in blood and feces obtained from a patient (a 5 year-old boy) with short-bowel syndrome (SBS) were compared during acidosis to results for the normal condition (no SBS symptoms). The taxonomical position of the lactobacilli found predominantly in the feces sample obtained 2 days before the fifth attack was also studied. The D-lactate level in serum obtained 1 day after the fourth attack was 10-fold higher than that for the normal condition, although there was not a great difference in L-lactate levels. D-Lactate (3.91 mM) and L-lactate (2.86 mM) were also detected in the feces samples collected 2 days before the fifth attack, while no lactate was detected in the feces sample for the normal condition. The counts of total fecal bacteria, especially anaerobic bacteria such as members of the family Bacteroidaceae, were found to be low. The counts of lactobacilli and the total population of lactobacilli relative to total fecal bacteria in the feces 2 days before the fifth attack (40.4%) were extremely high. In this case, a majority of the lactobacilli were D-lactate producers as determined by homolactic fermentation. These lactobacilli were identified as Lactobacillus delbrueckii subsp. lactis. The percentages of bifidobacteria relative to total fecal bacteria in feces samples obtained both 2 days before the fifth attack (50.9%) and for normal condition (61.9%) were also high, although these bacteria were L-lactate producers. In the feces samples for the normal condition, the D-lactate producers decreased to less than 10(9) per g, while the counts of L- or DL-lactate producers were 100-fold higher than the numbers in feces samples obtained 2 days before the fifth attack. These results suggested that an increase in the level of D-lactate producers, such as L. delbrueckii subsp. lactis, in the colon may be associated with the clinical expression of metabolic acidosis. 相似文献
33.
M Niwa M Ibaragi K Tsutsumi M Kurihara A Himeno K Mori M Ozaki 《Neuroscience letters》1988,91(1):89-94
We examined the specific rat 125I-alpha-rat atrial natriuretic peptide(1-28)[ANF-(99-126)] (125I-rANP) binding sites in the cerebral capillaries from the cerebral cortex of male adult Wistar rats. The binding of 125I-rANP at 37 degrees C was saturable and of high affinity with a Kd of approximately 100 pM and Bmax of 152 fmol/mg protein. Divalent cations, Mn2+ (2.2 mM) and Ca2+ (1.8 mM) potently inhibited the binding. The rank order for inhibition of the binding was rANP, alpha-human ANP and ANF-(101-126) greater than ANF-(103-126) and ANF-(103-125)"ANF-(103-123). These data on specific binding sites of ANP in cerebral capillaries suggest a possible role for ANP in the blood-brain permeability of water and electrolytes. 相似文献
34.
M Niwa K Shigematsu M Kurihara Y Kataoka T Maeda K Nakao H Imura H Matsuo H Tsuchiyama M Ozaki 《Neuroscience letters》1988,95(1-3):113-118
Specific binding sites of brain natriuretic peptide (BNP), a newly discovered peptide in the subfornical organ (SFO) of porcine brain were investigated, following incubation of related tissue sections with 125I-BNP, then using autoradiography and an image analysis coupled with computer-assisted microdensitometry. Specific 125I-BNP binding sites were found to be localized in the SFO, an area densely labeled by 125I-alpha-rat atrial natriuretic peptide and 125I-(Sar1,Ile8)-angiotensin II. Specific 125I-BNP binding to the SFO was displaced by unlabeled BNP, with a high affinity, and was calculated to be Ka = 0.385 x 10(-9) M and Bmax = 40.1 fmol/mg using a LIGAND computer program. Acquisition of these present findings enhances our knowledge of the physiology of BNP, atrial natriuretic peptides and angiotensin II system in the SFO. 相似文献
35.
Polo-like kinase 1 expression in medullary carcinoma of the thyroid: its relationship with clinicopathological features. 总被引:3,自引:0,他引:3
Yasuhiro Ito Yasushi Nakamura Hiroshi Yoshida Chisato Tomoda Takashi Uruno Yuuki Takamura Akihiro Miya Kaoru Kobayashi Fumio Matsuzuka Kanji Kuma Kennichi Kakudo Akira Miyauchi 《Pathobiology》2005,72(4):186-190
OBJECTIVE: Polo-like kinase 1 (PLK1) is one of the serine-threonine kinases that contributes to cell mitosis and is regarded as a marker of cellular proliferation. However, its protein expression in human carcinoma has not been studied in depth. In this study, we investigated PLK1 expression in medullary thyroid carcinoma by means of immunohistochemistry. METHODS: We immunohistochemically investigated PLK1 expression in 67 cases of medullary thyroid carcinoma. RESULTS: The PLK1 expression level was elevated in 43 of the 67 cases (64.1%). Furthermore, the expression level was directly linked to lymph node metastasis, advanced stage and male sex. All patients who were negative for PLK1 expression are currently alive without tumor recurrence, while 6 of the 43 PLK1-positive patients showed recurrence and 3 have already died of this disease. CONCLUSIONS: These findings suggest that PLK1 expression significantly reflects aggressive characteristics of medullary thyroid carcinoma. 相似文献
36.
Ota H Hayama M Nakayama J Hidaka H Honda T Ishii K Fukushima M Uehara T Kurihara M Ishihara K Hotta K Katsuyama T 《American journal of clinical pathology》2001,115(1):69-79
The specificity of monoclonal antibodies against gastric mucins (designated as HIK1083, PGM 36, and PGM 37) was studied immunohistochemically in normal, metaplastic, and neoplastic human tissues. These antibodies labeled class III mucin-producing cells identified by paradoxical concanavalin A staining in normal stomach, duodenum (Brunner gland), biliary tract, and main pancreatic duct; in mucinous metaplasia of pancreas and gallbladder; and in adenocarcinomas of stomach (90%), bile duct (80%), gallbladder (100%), pancreas (80%), lung (100% of goblet cell type adenocarcinomas), ovary (67% of mucinous carcinomas), and uterine cervix (100% of adenoma malignum tumors). Normal and neoplastic cells of esophagus, colon, salivary gland, kidney, endometrium, breast, prostate, and liver, as well as normal small intestine, lung, and uterine cervix, were all negative. The antibodies used should be valuable for the detection of class III mucin and class III mucin-producing cells in normal, metaplastic, and neoplastic tissues. 相似文献
37.
Atsuko Iwasa Yoshinao Oda Shuichi Kurihara Yoshihiro Ohishi Masafumi Yasunaga Izumi Nishimura Emi Takagi Hiroaki Kobayashi Norio Wake Masazumi Tsuneyoshi 《Pathology international》2008,58(12):757-764
Ovarian mature cystic teratomas (MCT) uncommonly undergo malignant transformation to squamous cell carcinoma (SCC). While alterations in the p53 tumor suppressor gene and protein have been shown, few studies have analyzed other molecular changes leading to this malignant conversion. The purpose of the present study was to investigate 21 samples of SCC arising in MCT for altered expression in known p53‐ and p16/Rb‐dependent cell cycle regulatory proteins, and the association between their expression and cellular proliferation and histological features. Overexpression of the p53 protein was observed in 14 SCC (67%), while four (19%) had point mutations in the p53 gene. Reduced expression of the p16 protein was observed in 18 SCC (86%), while p16 gene alterations (hypermethylation (29%) and point mutation (33%)) were found in 11 (52%). Furthermore, a statistically significant correlation was observed between p53 and Rb overexpression (P = 0.0010), and the overexpression of both p53 and Rb was respectively significantly correlated with increased cellular proliferation. The results indicate that alterations in both the p53 and p16‐Rb pathways are associated with SCC arising in MCT. 相似文献
38.
Xiao Liu Xiaohong Meng Lizhu Yang Yanling Long Yu Fujinami‐Yokokawa Jiayun Ren Toshihide Kurihara Kazuo Tsubota Kazushige Tsunoda Kaoru Fujinami Shiying Li East Asia Inherited Retinal Disease Society Study Group 《American journal of medical genetics. Part C, Seminars in medical genetics》2020,184(3):694-707
Stargardt disease 1 (STGD1) is the most prevalent retinal dystrophy caused by pathogenic biallelic ABCA4 variants. Forty‐two unrelated patients mostly originating from Western China were recruited. Comprehensive ophthalmological examinations, including visual acuity measurements (subjective function), fundus autofluorescence (retinal imaging), and full‐field electroretinography (objective function), were performed. Next‐generation sequencing (target/whole exome) and direct sequencing were conducted. Genotype grouping was performed based on the presence of deleterious variants. The median age of onset/age was 10.0 (5–52)/29.5 (12–72) years, and the median visual acuity in the right/left eye was 1.30 (0.15–2.28)/1.30 (0.15–2.28) in the logarithm of the minimum angle of resolution unit. Ten patients (10/38, 27.0%) showed confined macular dysfunction, and 27 (27/37, 73.7%) had generalized retinal dysfunction. Fifty‐eight pathogenic/likely pathogenic ABCA4 variants, including 14 novel variants, were identified. Eight patients (8/35, 22.8%) harbored multiple deleterious variants, and 17 (17/35, 48.6%) had a single deleterious variant. Significant associations were revealed between subjective functional, retinal imaging, and objective functional groups, identifying a significant genotype–phenotype association. This study illustrates a large phenotypic/genotypic spectrum in a large well‐characterized STGD1 cohort. A distinct genetic background of the Chinese population from the Caucasian population was identified; meanwhile, a genotype–phenotype association was similarly represented. 相似文献
39.
Angiogenic endothelium-specific nestin expression is enhanced by the first intron of the nestin gene 总被引:5,自引:0,他引:5
Aihara M Sugawara K Torii S Hosaka M Kurihara H Saito N Takeuchi T 《Laboratory investigation; a journal of technical methods and pathology》2004,84(12):1581-1592
Nestin is a member of intermediate filaments abundantly expressed in neural stem cells and glioblastomas. The nestin gene has four exons and three introns, and neural cell-specific expression is regulated by the second intron. We previously reported that nestin was invariably detected in the tumor endothelium in gliomas even though tumor cells were negative for nestin. In the present study, we further confirmed nestin immunostaining in tumor endothelium of a variety of common cancers, including lung, stomach, colon, and cervical carcinomas. We examined an endothelium-specific regulator using human umbilical vein endothelial cells (HUVECs) and human glioblastoma-derived U251 cells. In a luciferase reporter assay, the first intron plus 5' upstream promoter (5'UP) gave the highest activity, followed by 5'UP, and the second intron plus 5'UP. However, the assay values were much lower by HUVEC extracts than by U251 cell extracts. Although green fluorescent protein expression was positive over all U251 cells under either the first intron, second intron, or ubiquitously active CAG promoter, the fluorescence in HUVECs was limited to a few cells even under the first intron. This difference came from the growth feature of HUVECs which exhibit growth arrest by contact inhibition. We found that the nestin expression was specific to proliferative endothelium, by using proliferation markers in hemangioblastomas and in situ hybridization. Using an endothelial tube formation assay, tyrosine kinase domain-deleted VEGF receptor KDR effectively abolished the tube formation under the first intron. We suggest that the nestin expression in tumor endothelium is enhanced by the first intron. 相似文献
40.
This study investigated retrospectively the thoughts people had of World War II, especially the Battle of Okinawa at that time, and their current evaluation of their own wartime experience. A questionnaire survey was conducted, and 217 older adults, 114 women and 103 men between 65 and 88 years old, participated. Results indicated that men generally had more negative feelings than women at the end of the war. And psychological damages caused by traumatic war memories seemed to have persisted in not a few individuals in spite of over half a century since the end of the war. However, others had been more positive and accepting toward their wartime experiences. This difference appeared to be related to qualitative differences of various experiences, as well as the person's age. It is argued that a vigorous approach will be necessary for this sort of study of Japanese war victims from a number of viewpoints. 相似文献