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排序方式: 共有6831条查询结果,搜索用时 31 毫秒
31.
Tadashi Nomura MD ; Hiroto Terashi MD PhD ; Makoto Omori MD ; Atsushi Sakurai MD ; Takeru Sunagawa PhD ; Masumi Hasegawa MS ; Shinya Tahara MD PhD 《Wound repair and regeneration》2007,15(6):833-837
Hypertrophic scars (HS) are a consequence of abnormal wound healing. We examined fatty acids that are contained within, and participate in, every reaction through the membrane; then, we analyzed the percentage composition of the fatty acids in deepithelialized normal dermis (ND) and HS. In vivo HS samples were obtained from six patients undergoing surgical excision, and ND samples from five patients undergoing skin grafting surgery for excess. In vitro, cultured fibroblasts from HS and ND were also analyzed. The percentage composition of fatty acids extracted from all the samples was analyzed. In vivo, arachidonic acid (20:4) was significantly more abundant in HS than in ND, in the phospholipids from both whole tissue and cell membranes. In vitro, there were no significant differences among ND, HS, and 10% fetal calf serum. The results suggest that HS formation does not necessarily involve simple excess of 20:4; however, there are considerable differences in the percentage composition of 20:4 between ND and HS. Arachidonic acid probably participates in the formation and maintenance of HS, whereas in vitro cultured fibroblasts are affected largely by fetal calf serum. 相似文献
32.
33.
Yasushi Nishihira Chun‐Feng Tan Junko Hirato Junichi Yoshimura Kenichi Nishiyama Hideaki Takahashi Yukihiko Fujii Hitoshi Takahashi 《Neuropathology》2007,27(6):551-555
Two embryonal CNS tumors, atypical teratoid/rabdoid tumor (AT/RT) and primitive neuroectodermal tumor (PNET), may be confused with each other and misdiagnosed. Here we report an infant with a congenital supratentorial tumor, which was detected by fetal MRI at 37 weeks gestation. On routine histological examination, the tumor was composed mainly of small undifferentiated cells, among which many rhabdoid cells and occasional sickle‐shaped embracing cells were observed. No mesenchymal or epithelial areas were evident. Our impression was that the tumor was an atypical example of AT/RT. Immunohistochemically, almost all the tumor cells were strongly positive for vimentin. However, epithelial membrane antigen was notably negative, and most of the tumor cell nuclei were clearly positive for INI1. In addition, many tumor cells were positive for neurofilament protein. There were also occasional small areas containing many tumor cells positive for glial fibrillary acidic protein. Finally, a diagnosis of PNET, with a rhabdoid phenotype and expression of neuronal and glial markers, was made. In the present case, application of INI1 immunostaining was very helpful for distinguishing PNET from AT/RT. 相似文献
34.
目的 探讨胞嘧啶脱氨酶(cytimidine deaminase,CD)基因修饰神经干细胞及其基因表达。方法 通过构建真核表达质粒pCMVCD,限制性内切酶消化鉴定后,采用Lipofectamine 2000脂质体介导法转染新生大鼠室管膜下区神经干细胞(Neural stem cells,NSCs),G418筛选阳性克隆,加入不同浓度的5-氟胞嘧啶(5-Flourocytosine,5-FC),MTT比色法测定NSCs的生存率。结果 本实验成功地培养并鉴定了神经干细胞,并将CD基因成功地转染了神经干细胞,G418阳性NSCs对低浓度5-FC高度敏感。结论 CD基因修饰神经干细胞的离体实验研究为干细胞治疗研究提供依据。 相似文献
35.
N Yoshimura T Asada H Matsuda H Nohara T Higami M Nishiwaki N Mukohara M Chibana K Ogawa 《Kyobu geka. The Japanese journal of thoracic surgery》1990,43(2):157-159
A 17-year-old male patient with Marfan syndrome was admitted due to recurrent bilateral pneumothorax which had recurred totally 11 times during the past 3 years. For the treatment of obstinately continuing right pneumothorax resection of bullae in combination with pleuropexy using OK 432 was effective. Two months thereafter Bentall operation with a composite graft consisting of a woven Dacron tube and a Bj?rk-Shiley 27 mm aortic valve prosthesis was performed for his anuloartic ectasia. Left pneumothorax recurred 2 weeks after Bentall operation. But it was treated successfully with OK 432 injection into the left pleural cavity. Now, he is doing well as a student. 相似文献
36.
Y Takahashi S Yoshimura H Masago K Inouye T Shirai T Nagoya M Sakaguchi S Inouye S Katagiri 《Arerugī》1992,41(11):1611-1613
Airborne pollens collected in a pollen collector (Virtual Impactor) was treated with a fluorescein isothiocyanate-labeled monoclonal antibody (KW-S10) which was strictly specific to Japanese cedar pollen antigen (Cry j I). Flow cytometric analysis revealed that the intensity of fluorescence of the pollen samples treated with the antibody was greater than that of non-treated reference pollen or the antibody treated Hinoki-cypress pollen. By use of this method, it may be possible to display the airborne pollen concentration within 20 min after sampling. 相似文献
37.
Y Yoshimura K Tomimatsu T Nishimura A Miyake N Hashimoto 《The Journal of antibiotics》1992,45(5):721-734
As a part of our studies on cephalosporins bearing condensed-heterocyclic azolium methyl groups at the 3 position in the cephalosporin nucleus, we describe here the synthesis and antibacterial activity of 7 beta-[2-(2-aminothiazol-4-yl)2(Z)-methoxyiminoacetamido] cephalosporins (1-16, 7 beta-[2-(2-amino-5-chlorothiazol-4-yl)-2(Z)- methoxyiminoacetamido] cephalosporins (17,18) and 7 beta-[2-(5-amino- 1,2,4-thiadiazol-3-yl)-2(Z)-methoxyiminoacetamido) cephalosporins (19-23) containing a variety of condensed-heterocyclic triazolium methyl groups at the 3 position in the cephalosporin nucleus. These cephalosporins exhibited potent antibacterial activity, and it appears that condensed-heterocyclic triazolium as well as condensed-heterocyclic imidazolium rings are effective moieties for improving antibacterial activity and the spectrum of activity. Among the cephalosporins tested, 7 beta-[2-(2-aminothiazol-4-yl)-2(Z)-methoxyiminoacetamido]-3-(5- methyl[1,2,3]triazolo-[1,5-alpha]pyridinium-1-yl)methyl-3-cephem-4- carboxylate (9) and 7 beta-[2-(2-aminothiazol-4-yl)-2(Z)-methoxyiminoacetamido]-3-(6- methoxy[1,2,4]triazolo[1,5-alpha]pyridinium-1-yl)methyl-3-cephem-4- carboxylate (11) showed good antibacterial activity. 相似文献
38.
M Mochizuki T Watanabe K Yamaguchi K Yoshimura S Nakashima M Shirao S Araki K Takatsuki S Mori N Miyata 《American journal of ophthalmology》1992,114(2):123-129
Seroepidemiologic, clinical, and virologic studies were performed to determine whether human T-cell lymphotropic virus type I was closely associated with uveitis in two hospitals. One hospital was in an endemic area of the virus (Miyakonojo, Miyazaki) and the other hospital was in a less endemic area (Kurume). In the endemic area, the seroprevalence of the virus in patients with uveitis without defined causes (35.4%, 62 of 175 patients) was significantly higher than that in patients with nonuveitic ocular diseases (16.1%, 42 of 261 patients), or in patients with uveitis with defined causes (10.3%, eight of 78 patients). The seroprevalence in younger patients (20 to 49 years of age) with uveitis without defined causes in the area was 44.8% (30 of 67 patients), whereas it was only 9.3% (ten of 107 patients) in the other two groups. A similar observation was recorded even in the less endemic area (Kurume). Because the seroprevalence of the virus in the general population is known to be low in younger patients and to increase with age, these findings were interpreted to indicate that the association of human T-cell lymphotropic virus type I with uveitis was significant. Most patients, particularly those aged 20 through 49 years, had an intermediate uveitis characterized by a moderate inflammation in the vitreous body accompanied by an iritis and retinal vasculitis. The ocular symptoms in the patients differed from those of other types of uveitis common in Japan (Beh?et's disease, Vogt-Koyanagi-Harada's disease, and toxoplasmosis, for example).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
39.
Analysis of T Cell Receptor Variability in Fresh Tumor-infiltrating Lymphocytes from Human Head and Neck Cancer 总被引:1,自引:1,他引:0
Kazuaki Chikamatsu Masao Eura Koji Nakano Yuichi Kanzaki Hiroaki Matsuoka Keisuke Masuyama Takeru Ishikawa 《Cancer science》1994,85(6):626-632
In this study, we analyzed T cell receptor (TCR) gene rearrangements in tumor-infiltrating lymphocytes (TIL) freshly obtained from 15 patients with head and neck cancer using the reversely transcribed polymerase chain reaction (RT-PCR) method. These TILs showed preferential expression of Vα10, Vα8 and Vα1, detected in 13 (87%), 11 (73%), and 9 cases (60%), respectively. The TCRVβ gene revealed diversity without preferential usage. The head and neck region is exposed to bacteria and viruses, so it is possible that the tumor site can become infected and accumulate T cells involved in infection and inflammation. Therefore, we also investigated TCR gene usage in T cells infiltrating in chronic sinusitis mucosa to address the question of whether the Vα1, Vα8, and Vα10 subfamilies are characteristic in TIL from squamous cell carcinoma of head and neck. TCR Vα10 gene usage was also the most common in Vα segment in T cells infiltrating the sinus mucosa, but Vα and Vα8 were not detected in the T cells in sinusitis. These results indicate that the Vα10 subfamily, the preferred T cell population in both TIL and T cells in inflammatory disease, might he involved mainly in inflammation or infection. On the other hand, Vα1 and Vα8 appear to be relatively specific populations for antitumor immunity in head and neck cancer. 相似文献
40.
HTLV-I uveitis: a distinct clinical entity caused by HTLV-I. 总被引:16,自引:0,他引:16
M Mochizuki T Watanabe K Yamaguchi K Takatsuki K Yoshimura M Shirao S Nakashima S Mori S Araki N Miyata 《Japanese journal of cancer research》1992,83(3):236-239
Seroepidemiological, clinical and virological studies were carried out in an HTLV-I endemic area to find out if HTLV-I caused an intraocular inflammatory disorder, uveitis. The seroprevalence in patients with uveitis without defined etiologies (62/175, 35.4%) was significantly higher than that in patients with non-uveitic ocular diseases (42/261, 16.1%) or in patients with uveitis with defined etiologies (8/78, 10.3%). Moreover, the seroprevalence in young adults (20-49 years) with uveitis without defined etiologies was 30/67 (44.8%), whereas it was only 10/107 (9.3%) in the other two groups. The uveitis in HTLV-I carriers was characterized clinically by a moderate inflammation of the vitreous body accompanied by a mild iritis and retinal vasculitis. The proviral DNA of HTLV-I was detected by polymerase chain reaction from the inflammatory cells in the anterior chamber in 9 out of 9 seropositive patients with the uveitis, but not in any of the tested patients with other types of uveitis. These data, thus, indicate that HTLV-I causes a specific type of intraocular inflammation, uveitis. 相似文献