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排序方式: 共有1463条查询结果,搜索用时 15 毫秒
1.
Scott E Strome Elizabeth Martin Dallas Flies Dianne Khurana Diva Salomao Koji Tamada Andrei I Chapoval Jan L Kasperbauer Kerry D Olsen Lieping Chen 《Otolaryngology--head and neck surgery》2002,126(2):180-187
OBJECTIVES: CD62L was evaluated as a determinant of human pre-effector T cells. STUDY DESIGN AND SETTING: Phenotype and cytokine secretion profiles of CD62L cells were determined based on activation status. RESULTS: CD62L(Low) T cells demonstrated significantly higher secretion of interleukin (IL)-10 and interferon (IFN)-gamma than did CD62L(High) T cells. After activation, the majority of cells expressed high levels of the CD62L surface marker. Postactivation levels of IL-10 production remained elevated or unchanged. In a murine B16 melanoma model, freshly isolated CD62L(Low) tumor draining lymph nodes (TDLN) T cells showed increased secretion of IL-2 and IL-4 but not of IL-10 or IFN-gamma. The surface expression of CD62L and cytokine secretion patterns were maintained after activation with concomitant increases in IL-10. CONCLUSION: Our results provide evidence that CD62L(Low) T cells in TDLNs of progressively growing squamous cell carcinoma of the head and neck differ phenotypically and functionally from those of mouse origin. SIGNIFICANCE: Characterization of this human CD62L(Low) T cell population provides initial insight regarding novel surface markers in TDLN T cells that might correlate with antitumor reactivity. 相似文献
2.
Kazuhiko Yanai Tatsuo Ido Kiichi Ishiwata Jun Hatazawa Toshihiro Takahashi Ren Iwata Taiju Matsuzawa 《European journal of nuclear medicine and molecular imaging》1986,12(3):141-146
The endogenous hallucinogen, N,N-dimethyltryptamine (DMT), was labeled with carbon-11 and its regional distribution in rat brain studied. [11C]DMT showed higher accumulation in the cerebral cortex, caudate putamen, and amygdaloid nuclei. Studies of the subcellular distribution of [11C]DMT revealed the specific localization in the fractions enriched with serotonin receptors only when a very low dose was injected into rats. The proportions of the radioactivity in receptor-rich fractions were greatly enhanced by pretreatment with the monoamine oxidase inhibitor, pargyline. Specific binding of [11C]DMT to serotonin receptors in dog brain was demonstrated by a positron emission tomographic study in which 5-methoxy-N,N-dimethyltryptamine caused approximately 20% displacement of the radioligand from the receptors. 相似文献
3.
Yasuhiko Tamada Kikuka Yokochi Yoshimi Oshitani Yukiko Nitta Toshihiko Ikeya Kazuo Hara Katsushi Owaribe 《The Journal of dermatology》1995,22(3):201-204
We report a 73-year-old woman with typical clinical, histological and immunofluorescence features of pemphigoid nodularis. Direct immunofluorescence studies of prurigo nodularis-like lesions and peribullous skin showed the linear deposition of IgG and C3 at the basement membrane zone. Circulating IgG against the basement membrane was also detected by indirect immunofluorescence. The serum from the patient was shown to contain the autoantibody against 230 kDa hemidesmosomal antigen associated with bullous pemphigoid antigen. 相似文献
4.
Yasuhiko Tamada Hiromichi Takama Toshihiko Ikeya Takashi Yokochi Hijiri Mori Yoshinari Matsumoto 《The Journal of dermatology》1995,22(12):913-916
Lewis Y (Ley) antigen, a difucosylated tetrasaccharide found on type 2 blood group oligosaccharides of glycolipids and glycoproteins, is thought to be a phenotypic marker predictive of cell differentiation. The distribution of this antigen in human anagen hair follicles was examined by immunohistochemical staining using a monoclonal antibody (AH-6) to Ley. In the bulbar and suprabulbar portion of anagen hair follicles, Ley antigen was detected in the three layers of the inner root sheath. Subsequently, the positive staining became translocated to the innermost layer of the outer root sheath in the middle part of the hair follicles. In the upper portion of the hair follicles, Ley antigen was found in the outer cells of the outer root sheath. These findings suggested that the expression of Ley antigen in the anagen hair follicles was correlated with the processes of keratinization or terminal differentiation. 相似文献
5.
6.
K Iwata H Yoshimura Y Tsuji A Shirai F Uto T Tamada I Yamamoto T Tomiyama T Wada H Ohishi 《International journal of radiation oncology, biology, physics》1992,22(5):1109-1115
For intracavitary high dose-rate radiation therapy, a thermoluminescent [TL] sheet for in vivo measurement of spatial dose distribution around source has been recently developed. The TL sheet was found to have a linear response with a very wide dynamic range from at least 0.002 cGy to 5000 cGy for 60Co gamma-rays. This TL sheet (40 cm x 50 cm x 200 microns), which is composed of Teflon mixed with BaSO4:Eu doped powder, is very flexible and can be cut to the desired size. In addition, this sheet is easy to handle because of its insensitivity to room light. The spatial dose distribution is displayed in a color mode by using a newly developed TL sheet readout system. For a clinical application, the TL sheet was wrapped on an applicator for intracavitary radiation therapy of a rectal cancer and was inserted into the rectum. The location of the TL sheet could be confirmed with diagnostic X ray film. After irradiation with high dose-rate 60Co source, the in vivo relative dose distribution on the surface of the rectum was determined. This TL sheet provided a convenient means of measuring the relative dose distributions around 60Co sources of various patterns in intracavitary radiation therapy. 相似文献
7.
Flow karyotypes and chromosomal DNA contents of genus Triticum species and rye (Secale cereale) 总被引:3,自引:0,他引:3
Jai-Heon Lee Youzhi Ma Toshiyuki Wako Lian Cheng Li Kee-Young Kim Seong-Whan Park Susumu Uchiyama Kiichi Fukui 《Chromosome research》2004,12(1):93-102
The flow cytometry and chromosome imaging method were jointly used for analyzing genome content and chromosomal DNA content of hexaploid wheat (AABBDD), hexaploid triticale (AABBRR), tetraploid wheat (AABB), and AA, BB, DD genome donors and RR genome rye. Their genome sizes were 34.4 pg, 40.9 pg, 26.2 pg, 12.1 pg, 13.7 pg, 10.5 pg, and 16.9 pg, respectively. The 2C nuclear DNA content of BB genome donor with 13.7 pg was the highest value among the other genome donors, AA or DD. The genome content of tetraploid wheat, unlike hexaploid wheat or hexaploid triticale, was larger than the sum of the genomes of AA and BB genome donors. The DNA content of each chromosome ranged from 1.22 pg in DD genome donor to 2.61 pg in rye. Each chromosome peak was divided into three to four groups. Only one chromosome was included in the highest chromosomal DNA peak in hexaploid wheat, tetraploid wheat, DD genome donor and rye but two chromosomes in AA, BB genome donors, and hexaploid triticale. Correlation between 2C nuclear DNA content and chromosome density volume was the highest value compared with the other chromosomal parameters of chromosome area, or chromosome length. 相似文献
8.
Takahito Adachi Makoto Takeuchi Satomi Uno Motohisa Kato Kiichi Miya Shigetoyo Saji 《Surgery today》1997,27(12):1144-1149
Although tumor cryosurgery would be expected to produce beneficial immunological effects from the enhancement of anti-tumor
activity, under certain conditions the tumor may become enlarged and metastases promoted due to increased immunosuppressive
activity and a high zone tolerance. In the present study, we examined whether hepatocyteproliferating factors were produced
by the inoculation of freezing-thawing hepatic tissue (FTHT). Serum obtained from rats inoculated with FTHT increased DNA
synthesis, according to measurement by [3H]thymidine incorporation in primary cultured rat hepatocytes. This increase was dependent on the serum concentration, with
serum obtained on day 14 after the inoculation being the most potent for hepatocyte proliferation. The sensitized serum promoted
DNA synthesis nearly as much as serum obtained from a 70% hepatectomized rat, but slightly less than 10ng/ml hepatocyte growth
factor. The sensitized serum also protected hepatocytes from carbon tetrachloride (CCI4)-induced hepatotoxicity. Optical density measured by the 3-(4,5-dimethyl-thiazole-2-yl)-2,5-diphenyl tetrozolium bromide
(MTT) cytotoxicity assay was increased, and the release of aspartate aminotransferase, alanine aminotransferase, and lactate
dehydrogenase in medium was decreased by treating hepatocytes damaged by CCI4 with the sensitized serum. These results suggest that certain hepatocyte-proliferating and protective factors are induced
in serum by the inoculation of freezing-thawing hepatic tissue, and that the sensitized serum may be useful in the treatment
of liver failure. 相似文献
9.
10.
Summary The complete nucleotide sequences of beet necrotic yellow vein virus RNA-1 to RNA-4 of the Japanese isolate S (BNYVV-S) were determined and compared with those of French isolate (BNYVV-F2). The nucleotide sequences of the two isolates were very similar, differing by only 1.7% (RNA-1), 4.1% (RNA-2), 2.9% (RNA-3) and 3.6% (RNA-4), respectively. The differences of the amino acid sequences of the two isolates depended upon the open reading frames (ORF) as follows: P237, 1.4%; P22 (coat protein), 2.1%; 54k ORF, 3.4%; P42, 0.5%; P13, 1.7%; P15, 3.0%; P14, 7.0% P25, 6.4%; P31, 3.5%. Comparison of the coat protein and triple gene block (P42, P13 and P15) regions of RNA-2 with other isolates revealed that BNYVV-S was much more similar to the Yugoslavian isolate (BNYVV-Yu2) than to BNYVV-F2. The nucleotide differences between BNYVV-S and BNYVV-Yu2 were less than 1%. Based upon the grouping of BNYVV variants reported by Kruse et al. [10], BNYVV-S is thus considered to belong to the A type along with BNYVV-Yu2, whereas BNYVV-F2 is classified in the B type. Our data suggest that the Japanese isolate S may have been derived from European countries other than France or Germany.The BNYVV-S nucleotide sequences have been assigned the accession numbers D84410, D84411, D84412 and D84413 in the DDBJ. 相似文献