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排序方式: 共有2635条查询结果,搜索用时 15 毫秒
1.
Shinsuke Hamaguchi Yasuhisa Okuda Toshimitsu Kitajima Nobuhide Masawa 《Journal canadien d'anesthésie》2002,49(7):745-748
PURPOSE: To clarify the appropriate concentration and dose of hypertonic saline solution (HSS) for preventing delayed neuronal death in the hippocampal CA1 subfield after transient forebrain ischemia in gerbils. METHODS: Thirty gerbils were randomly assigned to five groups: physiological saline solution (PSS) group, ischemia/reperfusion treated with PSS 2 mL x kg(-1); 5% HSS group, treated with 5% HSS 2 mL x kg(-1); 7.5% HSS group, treated with 7.5% HSS 2 mL x kg(-1); 10% HSS group, treated with 10% HSS 2 mL x kg(-1); 20% HSS group, treated with 20% HSS 2 mL x kg(-1). Transient forebrain ischemia was induced by occluding the bilateral common carotid arteries for four minutes. Five days later, histopathological changes in the hippocampal area were examined, and the degenerative ratio of the pyramidal cells were measured according to the following formula: (number of degenerative pyramidal cells/total number of pyramidal cells per 1 mm of hippocampal CA1 subfield) x 100. RESULTS: In PSS and 20% groups, neuronal cell damage was observed five days after ischemia. In the other three groups, these changes were not observed. The degenerative ratios of pyramidal cells were as follows; PSS group: 91.6 +/- 5.6%, 5% HSS group: 7.2 +/- 1.6%, 7.5% group: 8.3 +/- 1.4%, 10% HSS group: 6.2 +/- 1.1%, 20% HSS group: 85.8 +/- 8.7% (P < 0.05; PSS and 20% HSS vs three other groups). CONCLUSION: This study demonstrates that 5, 7.5 or 10% HSS 2 mL x kg(-1) may prevent delayed neuronal death in the hippocampal CA1 subfield after cerebral ischemia/reperfusion in gerbils. 相似文献
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Tachykinin receptors of the NK2 type involved in the acetylcholine release by nicotine in guinea-pig bladder. 下载免费PDF全文
1. The effects of guanethidine and tachykinins on nicotine- and electrical stimulation-induced cholinoceptor responses were studied in isolated urinary bladder from the guinea-pig. 2. Acetylcholine release and the contractile response stimulated by nicotine were partially reduced by a sympathetic nerve blocker, guanethidine. Neurokinin A (but not substance P methyl ester or senktide) enhanced both acetylcholine release and contraction by nicotine in the presence of guanethidine. 3. Frequency-contraction curves (1 to 50 Hz) for electrical field stimulation (EFS) were partially reduced by atropine (1 microM), and after desensitization to alpha,beta-methylene adenosine 5'-triphosphate, the atropine-resistant contraction to EFS was completely abolished. Guanethidine, the tachykinin antagonist [D-Arg1, D-Pro2, Trp7,9, Leu11]-substance P and application of neurokinin A or substance P did not change the contractile response to EFS. Preganglionic nerve stimulation (5 Hz and 20 Hz) also evoked a similar response to EFS and was not influenced at all by guanethidine or neurokinin A. 4. We conclude that the ability of nicotine to release acetylcholine is enhanced both by endogenous tachykinins (probably released from sympathetic nerves) and by exogenously applied tachykinins as a result of interaction with NK2 receptors in the urinary bladder. 相似文献
4.
Yasuhisa Fujibayashi Hideyuki Taniuchi Kouichi Wada Yoshiharu Yonekura Junji Konishi Akira Yokoyama 《Annals of nuclear medicine》1995,9(1):1-5
The reductive retention of62Cu-PTSM was comparatively studied in the brain and Ehrlich ascites tumor cells by electron spin resonance spectrometry and nonradioactive Cu-PTSM. In the brain, only the mitochondrial fraction showed the ability to reduce Cu-PTSM, and the other subcellular fractions did not. In contrast, the cytosolic fraction of Ehrlich ascites tumor cells was the specific site of Cu-PTSM reduction. It was therefore considered that the retention of Cu-PTSM in the brain is closely related to mitochondrial reduction, most probably involving the mitochondrial electron transport system. 相似文献
5.
H Okamoto N Saijo T Shinkai K Eguchi Y Sasaki T Tamura Y Ohe A Kojima H Kunikane A Karato 《Annals of oncology》1992,3(10):819-824
To elucidate the factors which influence the value of hemoglobin, the nadir value of hemoglobin, frequency of blood transfusion and prognostic value of blood transfusion in patients with primary lung cancer during intensive chemotherapy, the hematological features of 124 patients entered into a randomized phase III study containing cisplatin were retrospectively analyzed. There was no difference in the percent nadir hemoglobin value of the first course of chemotherapy (% of pretreatment value) in any of the subgroups with respect to sex, body weight loss, performance status, age, stage, number of metastatic sites or treatment arms. The only predictive indicator for the nadir hemoglobin value in the first course of chemotherapy was the pretreatment value of hemoglobin. The equation for the regression line was y = 1.07 + 0.73x (R2 = 0.663, p < 0.001). The lowest nadir hemoglobin value (% of pretreatment value) during all chemotherapy courses was significantly lower in the subgroups older than 60 years and those with body weight loss. There was an inverse correlation between the accumulated dose of cisplatin and the lowest nadir hemoglobin value (p < 0.05). The frequency of blood transfusion in patients with more than two metastatic sites was significantly higher than in those with one or no metastatic sites (p < 0.05). Survival of patients who had required blood transfusion after chemotherapy was significantly shorter than that of patients who had not (p < 0.05). 相似文献
6.
Koibuchi Yukio; Iino Yuichi; Joshita Takashi; Yokoe Takao; Shinkai Hiroko; Kawashima Kenji; Kobayash Junya; Tanaka Sunao; Oyama Tetsunari; Hikino Toshiaki; Morishita Yasuo 《Japanese journal of clinical oncology》1995,25(6):273-277
A 66-year-old woman time of 10 days. One month after radicalmastectomy, there was local recurrence, followed by multiplepulmonary metastases, and the patient died of respiratory failure5 months after surgery. The gray-white-colored tumor measured13x12x;10 cm, and its border was well defined. The tumor wascomposed of diffusely growing round or polygonal cells withvesicular nuclei, prominent nucleoli, and ample cytoplasm containingeosinophilic inclusions. Lymph node involvement was widespread.Both vimentin and keratin were clearly demonstrated by immunohistochemicalstaining. Ultrastructural studies revealed that the MRT cellscontained cytoplasmic whorls of intermediate filaments. 相似文献
7.
Surgical treatment for the recurrence of colorectal cancer 总被引:2,自引:0,他引:2
Yasuhisa Yamamoto Hiroyuki Imai Sueharu Iwamoto Yutaka Kasai Tsukasa Tsunoda 《Surgery today》1996,26(3):164-168
We report the results of a retrospective study conducted on patients who developed recurrence following surgery for colorectal cancer, and present a practical plan to improve the survival rates. Of 974 patients who underwent surgery for colorectal cancer in our hospital during the 20 years between 1974 and 1993, 152 developed recurrence, as local recurrence in 70 (7.2%), as liver metastasis in 47 (4.8%), and as pulmonary metastasis in 35 (3.6%). The number of patients who underwent reoperation or curative resection was 54 (77.1%) and 13 (24.1%), respectively, of those with local recurrence, 16 (34.0%) and 6 (37.5%) of those with liver metastasis, and 6 (17.1%) and 6 (100.0%) of those with pulmonary metastasis. The 3- and 5-year survival rates were 13.4% and 8.9%, respectively, after reoperation for local recurrence, 14.4% and 0%, after reoperation for liver metastasis, and 53.3% and 53.3% after reoperation for pulmonary metastasis. Although evaluation was difficult owing to the small number of patients with lung metastasis, resection of a pulmonary lesion resulted in a good outcome. Furthermore, a significant difference in 3- and 5-year survival rates was observed between patients who underwent reoperation and those who underwent conservative treatment, for whom the survival rates were 0% and 0% following local recurrence, 4.6% and 0% following liver metastasis, and 0% and 0% following lung metastasis, at 3 and 5 years, respectively. These findings indicate that aggressive surgery for recurrence may result in a better outcome. 相似文献
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9.
Shinkai T De Luca V Zai G Shaikh S Matsumoto C Arnold PD Hwang R King N Trakalo J Potapova N Wong G Hori H Wong AH Ohmori O Nakamura J Kennedy JL 《Psychiatric genetics》2004,14(3):177-180
OBJECTIVE: Oxidative stress such as free radical-mediated neuronal dysfunction may be involved in the pathophysiology of schizophrenia. The human glutathione peroxidase (GPX1) is a selenium-dependent enzyme, which plays an important role in the detoxification of free radicals. We therefore hypothesized that the GPX1 gene, which is located on chromosome 3p21.3, may be involved in the pathophysiology of schizophrenia. The aim of this study is to examine whether a potentially functional polymorphism, a proline (Pro) to leucine (Leu) substitution at codon 197 (Pro197Leu) of the human GPX1 gene, is associated with susceptibility to schizophrenia. METHODS: We genotyped the Pro197Leu polymorphism in a total of 113 nuclear families that had a proband with schizophrenia. Genetic association was tested using the transmission disequilibrium test (TDT), the sib transmission disequilibrium test (STDT), and the family-based association test (FBAT). RESULTS: The minor allele (Leu) frequency was calculated to be 0.282. We could not find significant transmission disequilibrium of the alleles for the Pro197Leu polymorphism in the GPX1 gene in association with the presence of schizophrenia in our family sample (TDT, chi2=0.03, degrees of freedom=1, P=0.86; combined TDT-STDT, Z'=-0.052, P=0.47; FBAT, Z=0.000, P=1.000). CONCLUSION: The results of this study suggest that the GPX1 polymorphism is unlikely to be associated with susceptibility to schizophrenia. 相似文献
10.
Okamoto N Toribe Y Nakajima T Okinaga T Kurosawa K Nonaka I Shimokawa O Matsumoto N 《Journal of human genetics》2002,47(10):0556-0559
Chromosome 1p36 deletion syndrome is characterized by hypotonia, moderate to severe developmental and growth retardation,
and characteristic craniofacial dysmorphism. Muscle hypotonia and delayed motor development are almost constant features of
the syndrome. We report a 4-year-old Japanese girl with 1p36 deletion syndrome whose muscle pathology showed congenital fiber
type disproportion (CFTD) myopathy. This is the first case report of 1p36 deletion associated with CFTD. This association
may indicate that one of the CFTD loci is located at 1p36. Ski proto-oncogene −/− mice have phenotypes that resemble some of the features observed in patients with 1p36 deletion syndrome.
Because fluorescent in situ hybridization analysis revealed that the human SKI gene is deleted in our patient, some genes in 1p36, including SKI proto-oncogene, may be involved in muscle hypotonia and delayed motor development in this syndrome.
Received: March 4, 2002 / Accepted: July 7, 2002 相似文献