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101.
Shintaro Nemoto Kiyomitsu Yasuhara Katsutoshi Nakamura Yutaka Miyoshi Akira Sakai 《Annals of thoracic and cardiovascular surgery》2004,10(1):19-22
Carnitine is an essential cofactor for fatty acid (FA) metabolism, the predominant source of ATP in the normal aerobic heart. During myocardial ischemia, FA metabolism is impaired and tissue carnitine levels are depleted. Since the heart cannot synthesize carnitine, plasma carnitine could play an important role in maintaining myocardial carnitine levels during reperfusion. The purpose of this study was to determine the incidence of abnormal plasma carnitine concentrations in open heart surgery. Blood samples were obtained from eleven patients before, immediately after, and two hours after cardiopulmonary bypass (CPB). Total and free carnitine levels were significantly reduced immediately after CPB (p<0.01) and remained depressed until two hours after CPB (p<0.01 vs. pre CPB), while acyl carnitine levels were unchanged over the course of this study. These depressed free carnitine levels might affect cardiac metabolism in the heart after open heart surgery. Carnitine supplement might be a useful adjunct in the therapy after open heart surgery. 相似文献
102.
Tatsuo Shirota Mie Tashiro Kohsuke Ohno Akira Yamaguchi 《Journal of oral and maxillofacial surgery》2003,61(4):471-480
PURPOSE: This study investigated the effect of parathyroid hormone (1-34) [PTH(1-34)] on bone reactions after tibial placement of titanium screw implants into ovariectomized rats. MATERIALS AND METHODS: Twelve-week-old female Wistar rats were divided into 3 groups of 24. The first group (Sham group) was sham-operated; the second group (OVX group) was ovariectomized only; and the third group (PTH group) was subcutaneously administered 30 microg/kg PTH in the dorsal region 3 days per week starting the fourth week after ovariectomy until the end of the experiment. Titanium screw implants were placed in the proximal metaphysis of the tibia of all 3 groups at 168 days after surgery. The animals were killed 7, 14, 28, and 56 days after implantation. Undecalcified sections were prepared and evaluated by light microscopy. Histomorphometric measurements were obtained using a computer-based image analyzer to quantify the unit bone mass around the implant and the rate of implant-bone contact. RESULTS: When PTH administration was started 21 days after ovariectomy, the volume density of bone around implants in the PTH group was almost the same as that of the Sham group throughout the entire observation period. This finding suggests that not only can intermittent human PTH(1-34) administration prevent resorption of newly generated trabeculae around an implant but also it can aid in the recovery of bone volume lost due to ovariectomy. CONCLUSION: When dental implants are applied to jaw bone showing trabecular bone loss, it may be possible to increase bone density around an implant by intermittent human PTH(1-34) administration and thereby improve clinical results. 相似文献
103.
Activity labeling was applied to the olfactory systems of the terrestrial slug Limax valentianus using 2-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-2-deoxyglucose (2-NBDG), a fluorescent derivative of glucose. 2-NBDG was incorporated into cultured Limax olfactory interneurons, and this was partially blocked by the presence of a high concentration of glucose in the medium, indicating that a part of the uptake of 2-NBDG is mediated by glucose transporters. Next, in order to map odor-related neuronal activity in the primary olfactory center, tentacular ganglion, we injected 2-NBDG into the body cavities of slugs and exposed them to odors or clean air (control). In the odor-stimulated animals, the cell mass region was strongly stained. The digit-like extensions and the neuropil region were also stained in some animals. The control animals showed no staining. The neurons in the cell mass are thought to be involved in generating oscillating activities in the tentacular ganglion, and their activation may imply modulation of oscillatory activity during odor processing. Our results show that 2-NBDG is useful for mapping neuronal activity in vivo. 相似文献
104.
105.
Ken Yamaguchi Katsumi Aoyagi Ken-ichi Urakami Toyoharu Fukutani Noboru Maki Shigehiro Yamamoto Kotomi Otsubo Yoshio Miyake Tetsuro Kodama 《Cancer science》1995,86(7):698-705
Our previous study demonstrated that pro-gastrin-releasing peptide(31–98), or ProGRP, is a specific tumor marker in patients with small cell lung carcinoma (SCLC). Using a newly developed, highly sensitive enzyme-linked immunosorbent assay (ELISA) for ProGRP, we analyzed 1,446 samples including those obtained from 478 lung cancer patients to evaluate the clinical usefulness of this ELISA. Several properties indicated that ProGRP is a useful tumor marker for SCLC. First, ProGRP was specifically elevated in SCLC patients. In non-SCLC patients and patients with non-tumorous lung diseases, its serum level was very rarely elevated. Secondly, ProGRP was a reliable marker, in terms of the marked elevation of serum ProGRP levels in SCLC patients. Thirdly, serum ProGRP levels were elevated in SCLC patients even at a relatively early stage of this disease. Fourthly, changes in the serum ProGRP level showed an excellent correlation with the therapeutic responses in SCLC patients. Neuron-specific enolase (NSE) is accepted as a tumor marker of SCLC patients. With the aim of comparing ProGRP and NSE as tumor markers for SCLC patients, we measured serum NSE levels in all samples collected in the present study. We found that ProGRP was superior to NSE in terms of sensitivity, specificity and reliability. Therefore, we consider that ProGRP can play a major role as a clinical tumor marker for SCLC patients. 相似文献
106.
107.
H Kimura Y Yamaguchi M Fujino N Yamamoto 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1992,40(8):1177-1181
Lymph node metastasis was analyzed quantitatively with 4 categories and relation to post surgical survival and recurrence pattern was studied in patients with pN2 primary lung cancer who underwent relatively curative or relatively noncurative resection of the tumors. There was no relation between metastatic coefficient and post surgical survival, however, better survival was observed when the metastatic ratio and metastatic frequency were low and metastatic mode was random or skip pattern rather than sequential pattern. Metastatic coefficient and metastatic frequency were higher in cases with recurrence in lymph nodes but the former was lower and the latter was higher in cases with recurrence in intra-pulmonary dissemination or metastasis. There was no relation between metastatic coefficient and distant metastasis but metastatic frequency was lower in cases with recurrence in distant metastasis. Cases with sequential lymph node metastasis showed a tendency of lymph node recurrence and intrapulmonary metastasis and those with random or skip metastasis of lymph nodes had a tendency of distant metastasis. 相似文献
108.
109.
N. Yamaoka T. Yamaguchi E. Otsuji M. Kato T. Kotani K. Kitamura T. Takahashi 《British journal of cancer》1994,70(3):405-408
The monoclonal antibody (MAb) A7 has been used to treat patients with colorectal or pancreatic carcinoma with encouraging results. We therefore determined if MAb A7 would also react with gastric carcinoma cell lines. MAb A7 reacted with seven of eight gastric carcinoma cell lines tested. The intensity of the reaction, measured by flow cytometry, was equal to that of WiDr (colon) and HPC-YS (pancreas) cell lines. In nude mice bearing xenografts of the MAb A7-reactive gastric cancer line MKN45, the percentage injected dose of MAb A7 per g of tumour tissue on day 7 was 9.79; this value was 77% of that on day 1. The in vivo tumour-to-blood ratio of MAb A7 was 2.77 on day 7. Therefore, MAb A7 has long-term retention at binding sites as well as a high probability, high intensity and high specificity of reactivity against gastric cancer, which make it an ideal drug carrier for immunotargeted chemotherapy and immunodiagnosis. 相似文献
110.
Y Misawa T Hasegawa K Fukushima Y Sohara M Katoh F Murayama N Hasegawa H Horimi T Saitoh T Yamaguchi 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1992,40(7):1085-1088
Following cardiac surgery, approximation of sternum will produce systemic hypotension or elevation of left atrial and central venous pressures. A new criteria for delayed sternal closure is proposed. Sternal closure has to be delayed when mean left atrial or central venous pressures increased over 2 mmHg at the tentative closure. In seven cases (3.5%) of consecutive 201 patients was delayed the sternal closure under the above mentioned state, all survived and received the successful closure later. One of them died of congestive heart failure four months after the operation and one died of the rupture of the ascending aortic pseudoaneurysm eleven months after the initial operation. Microbiological examination of the mediastinal and pericardial contents obtained at the final sternal closure were negative in all cases. Comparing the total cardiopulmonary bypass time, ventricular fibrillation time, and myocardial ischemic time between in the secondary closure group and in the primary closure group, the total bypass time and the ventricular fibrillation time of the former were significantly longer than the latter, but the ischemic time revealed no difference. In conclusions, persistent elevation of left atrial or central venous pressures after cardiac surgery at the tentative sternal closure seems the reliable predictor for the delayed closure of the sternum. Careful post-operative management prevents serious mediastinal infection. Delayed sternal closure is preferable procedure for the patient with brittle hemodynamics after open heart surgery. 相似文献