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排序方式: 共有7045条查询结果,搜索用时 15 毫秒
31.
Seiitsu Ono Takashi Imai Shigeru Munakata Keiichi Takahashi Fumio Kanda Kazuki Hashimoto Takahiko Yamano Natsue Shimizu Koichi Nagao Mitsuo Yamauchi 《Journal of the neurological sciences》1998,160(2):565-147
During the last 10 years, we have demonstrated morphological and biochemical abnormalities of skin extracellular matrices in amyotrophic lateral sclerosis (ALS). However, currently little is known concerning collagen of the spinal cord in ALS. We measured the amount of collagen and characterized collagen at light and electron microscopic levels in posterior funiculus, posterior half of lateral funiculus and anterior horn of cervical enlargement of the spinal cord obtained from ten patients with ALS, 11 patients with other neurologic diseases (control group A), and ten patients without neurologic ones (control group B). In posterior half of lateral funiculus and anterior horn, (1) by light microscopy, there was no significant difference in vessel wall area between ALS patients and control groups A and B; (2) ultrastructurally, collagen bundles were more fragmented and widely separated, and the fibrils were randomly oriented in the perivascular space of capillaries in ALS patients, which were not observed in any areas of control groups or in posterior funiculus of ALS patients; and (3) the collagen contents in ALS were significantly lower (P<0.001 and P<0.001, respectively) than those in control groups A and B. Fragmented and widely separated collagen bundles in the interstitial tissue surrounding capillaries and markedly decreased amount of collagen in posterior half of lateral funiculus and in anterior horn of ALS could be related to the degeneration of the upper and lower motor neurons in the spinal cord in ALS, that is, selective neuronal vulnerability in ALS. 相似文献
32.
Kazuki Sato Toshiyasu Nakamura Yoshiaki Toyama Hiroyasu Ikegami Kaori Kameyama Shinichiro Takayama 《Hand surgery》2007,12(3):149-154
Calcium deposition in the skin, known as calcinosis cutis, is an uncommon disorder caused by an abnormal deposit of calcium phosphate in the skin. We report a case of idiopathic calcinosis cutis in fingertip treated with surgical excision followed by the occlusive dressing using aluminum foil, and obtained significant pain relief and round-shaped fingertip which looked normal. 相似文献
33.
Selective gap-junctional communication capacity of transformed and non-transformed rat liver epithelial cell lines 总被引:5,自引:2,他引:3
To investigate whether a selective intercellular communicationexists between transformed epithelial cells and their counterparts,the homologous and heterologous communication capacities offour rat liver epithelial cell lines were compared with theirexpression of transformed phenotypes. All four cell lines showedreasonably good homologous junctional communication capacity,as measured by the dye-transfer assay. In heterologous co-cultures,the non-transformed cell line IAR 20 did not communicate withthe transformed cell lines IAR 61 or IAR 27 F. Thesetwo cell lines showed a high degree of transformed phenotypessuch as cell morphology, growth in soft agar and expressionof -glutamyltrans-peptidase activity. Another cell line IAR27 E, showed the least degree of transformation and it communicatedwith IAR 20 cells. Thus, it appears that there is an inversecorrelation between the extent of expression of transformedphenotypes by rat liver epithelial cells and their ability tocommunicate with non-transformed counterparts. There was noheterologous intercellular communication between any combinationof IAR 27 E, IAR 27 F and IAR 61 cell lines. 相似文献
34.
M Yamasaki K Akagi K Niinomi S Kinoshita T Kitawaki K Yoshioka 《No to hattatsu. Brain and development》1989,21(3):215-221
Intracranial hemorrhage is a fatal complication associated with aplastic anemia. We have encountered four patients who experienced six episodes of intracranial hemorrhage (intracerebral hemorrhage; 3, subarachnoid hemorrhage; 2, and subdural hematoma; 1,). Intracranial hemorrhage occurred without traumatic episodes, and was followed by frequent hemorrhagic episodes in other parts of about one year duration. This disease is considered to recur after a short interval. The site, type and degree of intracranial hemorrhage varied, and therefore intracranial hemorrhage seemed to be caused not only by thrombocytopenia but also by multifactorial hemorrhagic tendency. Transfusion of platelet rich plasma, and administration of Glycerol and steroids produced good results for conservative therapy. Continuous spinal drainage for subarachnoid hemorrhage was a relatively safe and useful means of management. In the patients who showed precipitous deterioration, the CT scan findings indicated that the high-density-area was diffusely spread with an unclear border, just like "contusional hemorrhage". For such severe cases, blood evacuation with craniotomy and emergency splenectomy are considered to be valuable. 相似文献
35.
M Iyo T Yamasaki H Fukuda O Inoue K Suzuki H Shinotoh T Ito H Yonezawa M Nishio A Koseki 《Kaku igaku. The Japanese journal of nuclear medicine》1989,26(2):213-220
The effect of aging on 11C-N-methylspiperone binding to living human striatum was demonstrated using positron emission tomography. The 11 normal volunteers (22 to 72 years old) participated in this study. The uptake of 11C-N-methylspiperone in the brain following intravenous injection was highest in the striatum in individual subject. And the uptake in the striatum only gradually increased until the end of the study. The uptake of 11C-N-methylspiperone in cerebellum peaked within 10 minutes following injection and then rapidly dropped. The association rate constant "k3" was calculated from the slope of the radioactivity-ratio of striatum to cerebellum versus the equivalent time. The equivalent time was calculated from the radioactivity of cerebellum as an input function. The exponential decrease of the k3 value with aging was observed. The k3 value of the youngest subject (22 years old, male) was 0.035/min, while that of the oldest one (72 years old, male) was found to be 0.020/min. These data suggested that the dopaminergic activity through D2 dopamine receptors reduces with aging in human striatum. 相似文献
36.
37.
Chakraborty S Garg P Ramamurthy T Thungapathra M Gautam JK Kumar C Maiti S Yamasaki S Shimada T Takeda Y Ghosh A Nair GB 《Journal of medical microbiology》2001,50(10):879-888
This study identified 17 matching serogroups of Vibrio cholerae belonging to serogroups other than O1 and O139 isolated from human cases and from the environment during a concurrent clinical and environmental study conducted in Calcutta, a cholera endemic area. Isolates within these matching serogroups were compared by various phenotypic and genotypic traits to determine if the environment was the source of the organisms associated with the disease. Clinical strains of V. cholerae were resistant to a greater number of drugs and exhibited multi-drug resistance compared with their environmental counterparts. Except for the presence of the genes for the El Tor haemolysin and the regulatory element ToxR in most of the strains of V. cholerae examined, non-O1, non-O139 V. cholerae strains lacked most of the other known virulence traits associated with toxigenic V. cholerae O1 or O139. Restriction fragment-length polymorphism of virulence-associated genes, ribotypes and DNA fingerprints of strains of matched serogroups showed considerable diversity, although some gene polymorphisms and ribotypes of a few strains of different serogroups were similar. It is concluded that despite sharing the same serogroup, environmental and clinical isolates were genetically heterogeneous and were of different lineages. 相似文献
38.
Tanigaki K Han H Yamamoto N Tashiro K Ikegawa M Kuroda K Suzuki A Nakano T Honjo T 《Nature immunology》2002,3(5):443-450
RBP-J is a key mediator of Notch signaling that regulates cell fate determination in various lineages. To investigate the function of Notch-RBP-J in mature B cell differentiation, we generated mice that selectively lacked B cell RBP-J expression using conditional mutagenesis. Absence of RBP-J led to the loss of marginal zone B (MZB) cells with a concomitant increase in follicular B cells; in contrast, B1 cells in the peritoneal cavity were unaffected. Lack of RBP-J caused no defects in B cells maintenance, survival, plasma cell differentiation or activation. It is therefore likely that Notch-RBP-J signaling regulates the lineage commitment of mature B cells into follicular versus MZB cells. In addition, in mice with RBP-J-deficient B cells, had no obvious changes in immunoglobulin production in response to Ficoll, lipopolysaccharide or chicken gammaglobulin. In contrast, these mice exhibited increased mortality rates after blood-borne bacterial infection, which indicates that MZB cells play pivotal roles in the clearance of these bacteria. 相似文献
39.
40.
Fukazawa T Yamasaki K Ito H Kikuchi S Minohara M Horiuchi I Tsukishima E Sasaki H Hamada T Nishimura Y Tashiro K Kira J 《Tissue antigens》2000,55(3):199-205
The purpose of this study was to clarify the association of HLA-DRB1 and -DPB1 alleles with multiple sclerosis (MS) in Japanese, to determine whether optico-spinal MS (OS-MS) and conventional MS are immunogenetically distinct, and to verify the role of gender difference in HLA associations of MS. We studied HLA-DRB1 and -DPB1 polymorphisms in 166 Japanese patients with MS. Forty-seven patients were classified as having the optico-spinal MS (OS-MS) and 119 as having conventional MS. A lack of DPB1*0301 and a higher frequency of DPB1*0501 compared with controls (corrected P<0.0074; odds ratio=9.48) were found in OS-MS. By contrast, we found for the first time an association of DPB1*0301 with conventional MS in Japanese (corrected P=0.0444; odds ratio=3.28). Logistic analysis, adjusted for sex and age, revealed independent associations of DPB1*0301 (P=0.0004, adjusted odds ratio (aOR)=4.70), DPB1*0501 (P=0.0081, aOR= 2.50) and DRB1*1501 (P=0.0252, aOR=2.21) with conventional MS. However, the frequencies of DRB1*1501 and DPB1*0501 in male patients with conventional MS were equal to those in male controls while the DPB1*0301 frequency was increased in both male and female patients. We did not find any association of these HLA alleles with disease course and severity. In conclusion, OS-MS is a DPB1*0501-associated distinct subtype of MS, and DPB1*0301 is the most strongly associated allele with conventional MS in Japanese. In addition, gender plays an important role in HLA association with MS. 相似文献