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排序方式: 共有2497条查询结果,搜索用时 15 毫秒
1.
Yutaka Okishio Tadayoshi Takeuchi Akikazu Fujita Kiyotaka Suenaga Kaori Fujinami Satoru Munakata Tadashi Takewaki Fumiaki Hata 《Journal of Smooth Muscle Research》2005,41(3):163-174
Recently an essential role of interstitial cells of Cajal (ICC) within myenteric plexus (ICC-MY) was suggested in ascending contraction and descending relaxation in the mouse ileum. The role of ICC in these neural reflexes was examined in the distal colonic segments prepared from the wild type and c-kit mutant, W/W(V) mice, in the present study. Localized distension of the segments from the wild type mice by using a small balloon resulted in ascending contraction and descending relaxation. In the segments from the mutant mice, localized distension also induced these neural reflexes similar to those observed in the wild type mice. Immunohistochemical examination demonstrated that ICC-MY and ICC present in muscle layers (ICC-IM) were severely disrupted in the mutant mouse, but only ICC, present within submucosal plexus (ICC-SMP), remained unchanged. In the small strips with ICC-SMP absent prepared from the mutant mouse, electrical field stimulation induced contraction or relaxation in the absence or presence of atropine, respectively. It was suggested that ICC have no important role in the ascending and descending neural reflexes in the mouse distal colon, this is in direct contrast to the role of ICC-MY in the ileum. 相似文献
2.
Shinichi Suzuki Kiyotaka Imoto Keiji Uchida Naoki Hashiyama Yoshinori Takanashi 《Annals of thoracic and cardiovascular surgery》2005,11(6):424-428
This report describes the use of transluminal endovascular grafting for the treatment of a presumed aortoduodenal fistula. The patient was a 71-year-old man who had undergone resection and graft replacement for an abdominal aortic aneurysm. Three years after operation, melena was caused by perforation of the duodenal wall by a pseudoaneurysm at the proximal graft anastomosis. The pseudoaneurysm was treated by transluminal endovascular grafting. The pseudoaneurysm was subsequently thrombosed and absorbed. The ulcer-like lesions at the site of the duodenal wall perforated by the pseudoaneurysm also resolved. Endovascular stent-grafts may have a role to play in management of aortoduodenal fistula. 相似文献
3.
Localization of bone marrow-originated cells in the central nervous system (CNS) of the rat was investigated by using bone marrow chimeras. In order to do this, Lewis rats which carry major histocompatibility complex (MHC) class I antigens haplotype 1 (RT1.Al) were reconstituted with (Lew X PVG)F1 (RT1.Al/c) bone marrow cells after lethal irradiation. Transferred bone marrow cells were detected by immunohistochemical staining using a monoclonal antibody, OX27, specific for haplotype c of rat MHC class I antigens (RT1.Ac). The spleen and thymus of chimeric rats were fully reconstituted with transferred F1 cells 4 weeks after bone marrow transplantation. At this stage, mononuclear cells in the subarachnoid space of the CNS expressed OX27 antigen indicating that they were of bone marrow origin. A few OX27-positive blood cells were scattered in the CNS parenchyma 4-12 weeks after reconstitution. Ramified microglia, however, remained OX27-negative. Bone marrow-derived microglia were not observed throughout the period of examination until 24 weeks. In addition, experimental allergic encephalomyelitis (EAE) was induced in chimeric rats in order to augment the expression of MHC class I antigens on microglia. Even under this condition, no OX27-positive microglia were observed. Taken together, ramified microglia might be of neuroectodermal origin and there is little possibility that the microglia are derived from the bone marrow. However, if the ramified microglia are derived from blood cells, the microglia may be expected to have characteristic cell kinetics from the following points: (1) the precursor cells of the microglia may enter the CNS only at the perinatal stage; and (2) even under the condition in which lymphocytes and macrophages enter the CNS as observed in EAE, the precursor cells of the microglia are not supplied from the blood. 相似文献
4.
5.
Kuniaki Nakahara Satoru Shimizu Satoshi Utsuki Sachio Suzuki Hidehiro Oka Kiyotaka Fujii 《Child's nervous system》2007,23(8):863-865
Objects We evaluated whether the presence of lacunar skull deformity (LSD) with myelomeningocele is a predictive factor for subsequent
hydrocephalus development.
Materials and methods We reviewed the clinical and radiological records of 18 infants with myelomeningocele, divided the patients into groups with
(group A, n=9) and without (group B, n=9) ventriculomegaly at birth and assessed whether the presence of LSD was predictive of the necessity for ventriculoperitoneal
shunt (VPS) placement.
Results LSD was present in five group A patients. All nine group A patients underwent VPS placement. Among the group B patients, five
had LSD; they underwent VPS placement. A significantly higher proportion of those with ventricle enlargement or LSD at birth
required VPS placement (p=0.0001).
Conclusion Adding to the ventriculomegaly at birth, the presence of LSD alerts to the necessity to monitor these infants closely to determine
the necessity for VPS placement. 相似文献
6.
Kiyotaka KUROSE Toshikazu MASUMOTO S. M. Fazle AKBAR Kojiro MICHITAKA Norio HORIIKE Morikazu ONJI 《Digestive endoscopy》1997,9(1):34-37
Abstract: Fifty -two patients with primary biliary cirrhosis (PBC), 10 of whom were 65 years or older at the time of diagnosis, were investigated by laparo-scopy. Laparoscopic findings in these 10 patients were evaluated and compared with those in younger patients. The 10 cases were composed of nine females and one male, and two had been diagnosed as having symptomatic PBC with skin itching, while the remaining eight had asymptomatic PBC. Two, seven and one case were in Scheuer's stage I, II and III, respectively, and eight had chronic non-suppurative destructive cholangitis (CNSDC) on liver biopsy specimens. The majority of senescent PBC patients had typical findings of the early stage of PBC on the liver surface; mild undulations in nine and reddish patches in eight. The laparoscopic findings in senescent PBC were relatively mild. 相似文献
7.
Takeo MAEKAWA Kiyotaka YABUKI Koichi SATO Takanori HABA Kaoru OGAWA Michio MATSUMOTO 《Digestive endoscopy》1998,10(1):46-50
Abstract: A 63-year-old man was hospitalized because of jaundice and anorexia. An upper gastrointestinal series and hypotonic duodenography revealed circumferential sclerosis and stenosis of the duodenal wall. Endoscopic examination disclosed an ulcer, the upper margin of which was located at the papilla of Vater. The papilla was situated in the base of the ulcer. Endoscopic retrograde cholangiopancreatography disclosed mild dilatation of the common bile, intrahepatic bile and pancreatic ducts, but with neither severe stenosis nor occlusion. Nevertheless, there was some degree of circumferential compression and mild stenosis of the terminal portions of the bile and pancreatic ducts, as potential causes of obstructive jaundice in this patient. Computed tomographic examination of the abdomen revealed a tumorous lesion at the duodenal bulb. Because malignancy in the duodenum could not be ruled out, a pancreatoduodenectomy was performed. Histopathological examination showed a postbulbar duodenal ulcer, associated with inflammation of the papillary orifice and fibrosis of the region near the papilla. There was no evidence of a tumorous lesion. In this case, a postbulbar duodenal ulcer may have caused obstructive jaundice. 相似文献
8.
Pituitary Adenylate-Cyclase-Activating Polypeptide (PACAP) Binding Sites and PACAP/Vasoactive Intestinal Polypeptide Receptor Expression in Human Pituitary Adenomas 下载免费PDF全文
9.
10.
Mikio Watanabe Dr. Yoshinori Iwatani Tatsunari Kaneda Yoh Hidaka Nobuaki Mitsuda Yasuhiko Morimoto Nobuyuki Amino 《American journal of reproductive immunology (New York, N.Y. : 1989)》1997,37(5):368-377
PROBLEM: Pregnancy affects the maternal immune system and the clinical course of maternal diseases. Here we report the changes in the detailed lymphocyte subsets of helper T cells, suppressor T cells, CD5+ B cells, T cell receptor (TCR) αβ-positive T cells (Tαβ cells), TCRαβ-negative T cell (Tγδ cells), and others during and after pregnancy through to one year postpartum, and discuss the significance of the changes. METHOD: The absolute numbers of helper T cells, suppressor T cells, cytotoxic T cells, TCRαβ-negative T cells (Tγδ cells), CD5— B cells, CD5+ B cells, and NK cell subsets were examined by two-color flow cytometry in peripheral blood from 51 healthy non-pregnant women, 106 healthy pregnant women, and 148 healthy postpartum women. RESULTS: In early pregnancy, the numbers of suppressor T cells and NK cells with strong cytotoxicity (NK+++ cells) increased, and the number of cytotoxic T cells decreased. In late pregnancy, the helper T cell and NK+++ cell numbers decreased. Tαβ, CD5— B and CD5+ B cells decreased during pregnancy. After delivery, helper T cells and cytotoxic T cells increased from 1 to 4 months postpartum, and suppressor T cells increased at 7 months postpartum. TCRαβ-negative T cells increased at 4 to 10 months postpartum. Both CD5— and CD5+ B cells decreased further at 1 month postpartum, but CD5+ B cells increased markedly at 7 to 10 months postpartum. CONCLUSIONS: These data indicate that 1) early increases of suppressor T cells and NK+++ cells during pregnancy may be related to the mechanism to accept or reject the fetus in early pregnancy, respectively; 2) late decreases of helper T cells and NK+++ cells may be related to the maintenance of pregnancy: 3) postpartum increases of helper T cells, cytotoxic T cells, TCRαβ-negative T cells (Tγδ cells), and CD5+ B cells may be related to the postpartum aggravation of autoimmune diseases; and 4) the immunological effects of pregnancy remains until about 1 year after delivery. 相似文献