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排序方式: 共有788条查询结果,搜索用时 11 毫秒
91.
Yoshifumi Nakayama Seiji Naito Masahiro Ryuto Yasuaki Hata Mayumi Ono Katsuo Sueishi Sohtaro Komiyama Hideaki Roh Michihiko Kuwano 《Clinical & experimental metastasis》1996,14(5):466-474
We developed a modifiedin vitro invasion assay system using monolayers of vascular endothelial cells. A type I collagen gel was formed in plastic dishes, and overlaid with type IV collagen. Calf pulmonary arterial endothelial (CPAE) cells were seeded onto these plates, and incubated until they reached confluence. Five human renal cell carcinoma cell lines with various metastatic potentialsin vivo were then seeded on the monolayer CPAE cells, and their colony formation and invasion activities were examined for 9 days. At day 4, the highly metastatic cell lines increased the number of colony foci on monolayer CPAE cells several fold higher than their poorly metastatic counterpart. The horizontal spreading patterns were also different between poorly and highly metastatic cell lines. On day 9, the number of carcinoma foci that penetrated the monolayer of CPAE cells and type IV collagen sheets into type I collagen gels in highly metastatic cell lines greatly increased as compared with that of poorly metastatic cell lines. Ourin vitro invasion assay using monolayer CPAE cells would be useful to evaluate protease activities and colony formation during invasion. 相似文献
92.
Takeshi Miyairi Shinichi Takamoto Yutaka Kotsuka Atsuko Takeuchi Katsuo Yamanaka Hajime Sato 《European journal of cardio-thoracic surgery》2005,28(1):97-101; discussion 102-3
OBJECTIVE: Retrograde cerebral perfusion (RCP) is used as an adjunctive method to hypothermic circulatory arrest to enhance cerebral protection in patients undergoing thoracic aortic surgery. It remains unclear whether RCP provides improved neurological and neuropsychological outcome. METHODS: Forty-six patients undergoing thoracic aortic surgery using RCP, and 28 undergoing coronary artery bypass grafting (CABG; n = 28) with CPB, were enrolled in the study. Patients receiving RCP were subdivided into two groups, those with less than 60 min of RCP (S-RCP; n = 27) and with 60 min or more (L-RCP; n = 19). The patients' neurocognitive state was assessed by the revised Wechsler Adult Intelligence Scale a few days before operation, at 2-3 weeks and 4-6 months after operation. RESULTS: There were no stroke, seizure, and hospital mortality in either group. Significant decline between baseline and early scores were seen in three subtests (digit span, arithmetic, and picture completion) for S-RCP and four (digit span, arithmetic, picture completion, and picture arrangement) for L-RCP. Significant decline between baseline and late scores were seen in one subtest (arithmetic) for S-RCP, four (digit span, arithmetic, picture completion, and picture arrangement) for L-RCP, and one (object assembly) for CABG. The mean change of scores for one late test (digit symbol) was significantly lower in S-RCP than in CABG. The mean change of scores for three early tests (digit span, vocabulary, and picture arrangement) and four late tests (information, digit span, picture completion, and picture arrangement) were significantly lower in L-RCP than in CABG. Stepwise logistic regression analysis disclosed that, after considering the other variables, significant difference in test score changes were observed between CABG and L-RCP for two early tests (picture completion and digit symbol) as well as for three late tests (digit span, similarities, and picture completion). None of test score changes showed significant difference between CABG and S-RCP. CONCLUSIONS: The neurocognitive outcome in patients undergoing RCP less than 60 min were comparable with patients undergoing CABG without circulatory arrest. Prolonged RCP of 60 min or more in patients undergoing surgery of the thoracic aorta was associated with postoperative neurocognitive impairment. 相似文献
93.
A case of a 14 month old Japanese female infant presenting with nasal glioma Is reported. The tumor had been noticed at the nasal radix since birth and had slowly and progressively enlarged. There was no communication between the tumor and the cranial cavity on radiological examination. The tumor was macroscopically anchored to the nasal septum by a fibrous stalk, and histologically consisted of nests or trabeculae of either polygonal or spindle cells with plump eosinophilic cytoplasm and oval nuclei, separated by vascular-rich connective tissue intermingled with multinu-cleated giant cells. These tumor cells were immunohisto-chemically positive for glial fibrillary acidic protein as well as for S-100 protein and vimentin. An electron microscopic examination revealed collagen fibers and basal lamina between the tumor cells and the fibroblasts. Tumor cells possessed abundant intermediate filaments, which showed occasional Rosenthal fiber-like structures, in their cytoplasm and processes. A few oligodendrocytes and cilia of 9 micro-tubule doublets either with or without 2 central microtubules were also noted. These clinicopathological findings suggested that this tumor was once an encephalo(meningo)cele, which probably degenerated as a result of the loss of intracranial communication and then appeared to be isolated from the intracranial tissue. 相似文献
94.
The relationship between changes in intracellular free calcium concentration (Cai2+) and cell functions is becoming more clear, since it has become possible to measure Cai2+ in a living cell. There are, however, still unsolved questions concerning the role of Ca2+ in cellular signal transmission. It is not easy to relate Ca2+ signalling to the functions of a living cell. It is possible to control the amount of Ca2+ using calcium channel blockers, but it is still almost impossible to elucidate the relationship between Ca2+ and cellular functions by controlling Ca2+ signalling. One approach to solving this problem is to develop and use protein kinase inhibitors. Inhibitors specific to Ca2+/calmodulin-dependent protein phosphorylation, which is one of the important network systems of the Ca2+ signalling, attract interest among many researchers. The substances that can control Ca2+ signalling include: 1) calcium channel blockers, 2) calmodulin antagonists, and 3) Ca2+/calmodulin-dependent protein kinase inhibitors. Each substance has a different site of action. In this article, the action of KN-62, an inhibitor specific for Ca2+/calmodulin protein kinases (CaM kinases) will be described. 相似文献
95.
96.
Hiroko Kawai Mitsuru Kawamura Satoshi Mochizuki Katsuo Yamanaka Hiroshi Arakaki Kuniaki Tanaka Juro Kawachi 《Brain and nerve》2002,54(4):307-311
We never forget how to ride a bicycle, and it is thought that procedural memories are retained for a long time. Recently, it was reported that patients with dementia of the Alzheimer type(DAT) could not only acquire, but also retain, long-lasting procedural memories. Previous group studies had shown procedural memory retention times of only 1 month in DAT patients, while amnesic patients and healthy people could retain such memories for 12 months. The relationship between the ability to retain procedural memory and the stage of the disease is not clear, as to date there has been no longitudinal study of procedural memory retention in DAT patients. Thus, we examined DAT patients' ability to retain long-term procedural memories (after 1, 5 and 20 months), and analyzed the relationship between procedural memory ability and the progress of disease. Motor-type procedural memory was examined using the mirror tracing task and the bi-manual coordinated tracing task. All three of the DAT patients showed improvement in their performance. The time required for the tracing was reduced between trials, and the improvement did not disappear between sessions, or rather, their times further decreased in subsequent sessions. Even the most severe DAT patient (Mini Mental State Examination(MMSE) score of 4) was able to acquire the procedural memory and retain it for at least 3 months. Furthermore, one of the subjects showed retention of the procedural memory at 20 months. Our results suggest that DAT patients can retain procedural memories for extended periods, with no relationship between retention ability and disease progression. It is possible for even severely demented patients to acquire and retain motor-type procedural memories. Cognitive rehabilitation in DAT appears to be effective, and it is possible for DAT patients to learn new things. It may be that DAT patients can ameliorate their quality of life by using retained procedural memory. 相似文献
97.
Tsutomu Sakuma Katsuo Usuda Masashi Handa Gunji Okaniwa Tasuku Nakada Shigefumi Fujimura Michael A. Matthay 《Surgery today》1997,27(8):762-765
Alveolar fluid clearance was studied in the resected lung of a 58-year-old man who had undergone exploratory thoracotomy 9
days earlier. An isosmolar albumin solution was instilled into the distal air spaces, and the albumin and electrolyte concentrations
were measured over 4h. Alveolar sodium and fluid clearance had increased by nearly 200% from the control values in the resected
lungs of patients without prior thoracotomy (n=5), and histological examination showed that the number of alveolar type II epithelial cells was markedly elevated. These
results suggest that an increase in the number of alveolar type II cells may accelerate alveolar fluid clearance under certain
clinical conditions. 相似文献
98.
Takehiko Shimoyama Ryuta Suzuki Katsuo Yoshiya Yasushi Yamato Teruaki Koike 《General thoracic and cardiovascular surgery》2003,51(4):167-171
A 73-year-old woman evidencing an abnormal shadow on chest X-ray film since 1993 was admitted after a tumor of the left 8th rib was diagnosed in 2001. Computed tomography showed a low-density mass with coarse calcification arising from the left 8th rib and protruding into the abdominal cavity. The tumor was diagnosed as low-grade chondrosarcoma by incision biopsy and was resected together with the left 7th, 8th, and 9th ribs. The chest wall was reconstructed using Marlex mesh. Histological findings were compatible with Grade I chondrosarcoma. The patient had a long clinical course without distant metastasis thanks to the tumor's low malignancy. 相似文献
99.
Rats were trained to lever-press for intracranial self-stimulation (ICSS) with electrodes implanted in the ventral tegmental area (VTA). The effect of inescapable footshock on response rates to ICSS was examined in the present study. Markedly decreased response rates to ICSS were observed 15 min to 24 h following inescapable footshock. Naloxone (10.0 mg/kg) itself was without effect on response rates to ICSS, but completely antagonized the decreased response rates by the stressor treatment. A relatively low dose of methamphetamine (0.5 mg/kg), which showed no effect on ICSS rates in naive rats, also antagonized the decreased response rates to ICSS. The present results suggest that inescapable footshock may release endorphin in the mesolimbic or mesocortical area; the released endorphin may act on dopaminergic nerve endings and interrupt dopaminergic transmission. The decreased activity of dopaminergic neurons may cause the decreased response rates to ICSS. 相似文献
100.
Robert L. Wilson Katsuo Kamata James C. Bigelow George V. Rebec R. Mark Wightman 《Brain research》1986,370(2)
An increase in the concentration of ascorbate in the extracellular fluid of the rat striatum following systemic amphetamine administration previously has been demonstrated with the use of in vivo electrochemistry, push-pull cannula and in vivo dialysis. In this report, the effect of infusions of amphetamine into the substantia nigra on extracellular ascorbate levels in the striatum is further investigated by in vivo electrochemistry. Electrolytic lesions in the crus cerebri of the striatonigral pathway abolish this effect. Furthermore, these lesions abolish the effect of systemic amphetamine in the striatum ipsilateral to the lesion but not on the contralateral side. This phenomenon is independent of neostriatal dopamine or γ-aminobutyric acid since levels were shown to be unchanged relative to the intact side. These results lend further support to the hypothesis that ascorbate secretion in the striatum after amphetamine is mediated in the central nervous system, and indicate that a pathway that courses through the crus cerebri is necessary for this release. 相似文献