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101.
102.
103.
T Kaihoh T Masuda N Sasano T Takahashi 《The Tohoku journal of experimental medicine》1986,149(1):1-10
Surgical and autopsy specimens of normal pancreas from three human adults were submitted to morphometry of Langerhans islets and so-called extra insular islet cells, by measuring the islet radii on serial sections immunostained for either insulin or glucagon. All the islets contained in a test volume were measured including single cells, and the distribution of their radial sizes was studied. It was found that the distribution of islets was strongly skewed and continuous, with the majority of islets having radial values near to the minimum. From the fact that only one peak was found in the distribution curve, it is concluded that in spite of the distinction previously made between islets of Langerhans and so-called extra-islet cells, they are in fact both part of a continuous distribution. Moreover, the Weibull function, assumed as the theoretical distribution, fit well with the empirical histograms, giving support for the contention of continuous distribution with a single peak. Although the small islets account for a majority of the number of islets, they account for only a very small percentage of the islet volume. This is thought to indicate that the bulk of the endocrine functions of the pancreas are carried out by large islets, whereas the so-called extra-islet cells are likely to be their precursors. With regard to the cellular structure of the islets, it was found that the smaller the islet, the smaller the percentage of islets containing A cells, with the vast majority of cells in the smallest islets (often single cells) being B cells. 相似文献
104.
105.
Komaki K Sakuma M Ishigaki H Hozawa H Yamamoto Y Takahashi T Kumasaka N Kagaya Y Ikeda J Watanabe J Shirato K 《The Tohoku journal of experimental medicine》2003,199(1):49-57
We examined whether differences in the location of myocardial hypertrophy influence the right ventricular diastolic function in patients with non-obstructive hypertrophic cardiomyopathy using cineangiography. Biplane right ventriculography was performed in 34 subjects (normal = 14, asymmetric septal hypertrophy = 9, apical hypertrophy = 11) during cardiac catheterization. In patients with asymmetric septal hypertrophy, compared with apical hypertrophy and normal groups, the indices of the right ventricular diastolic function including right ventricular peak filling rate and filling fraction of rapid filling phase were lower and the time to peak filling rate was prolonged. But in patients with apical hypertrophy, these indices were not significantly different compared with normal. There were no differences in right ventricular ejection fraction and cardiac index among the three groups. These data suggest that the location of the myocardial hypertrophy of the left ventricle is a significant factor affecting the right ventricular diastolic filling in non-obstructive hypertrophic cardiomyopathy. 相似文献
106.
Nakagawa M Ooie T Takahashi N Taniguchi Y Anan F Yonemochi H Saikawa T 《Pacing and clinical electrophysiology : PACE》2006,29(6):607-613
OBJECTIVES: The aim of this study was to investigate the effects of the menstrual cycle on QT interval dynamics and the autonomic tone in healthy women. METHODS: Holter ECGs were recorded in 11 healthy women aged 18-32 years during the follicular and luteal phases of their regular menstrual cycle. The interval from QRS onset to the apex (QaT) and to the end of the T-wave (QeT), the interval between the apex and the end of the T-wave (Ta-e), and RR intervals were measured automatically in the course of 24 hours by Holter ECGs. The QeT/RR, QaT/RR, and Ta-e/RR relationships were evaluated in each subject. The autonomic tone was assessed by the serum catecholamine level at rest and heart rate variability was measured by Holter ECGs. RESULTS: (1) The follicular and luteal phases did not differ significantly with respect to the slopes of the QeT/RR, QaT/RR, and Ta-e/RR relationships. However, QeT and QaT intervals were significantly shorter for all RR intervals in the luteal than in the follicular phase (P < 0.0001). (2) The serum progesterone concentration was significantly higher in the luteal than in the follicular phase (P < 0.001). (3) Noradrenaline was significantly higher in the luteal than in the follicular phase (P < 0.05). There was no significant difference in the follicular and luteal phases with respect to heart rate variability measurements. CONCLUSIONS: Our results suggest that the menstrual cycle affects the QT intervals. The observed shorter QT interval during the luteal than the follicular phase may be attributable to the increase in serum progesterone and sympathetic tone. 相似文献
107.
Kotani N Hashimoto H Kushikata T Yoshida H Muraoka M Takahashi S Matsuki A 《Critical care medicine》2001,29(10):1943-1949
OBJECTIVE: Anesthesia and surgery decrease antimicrobial and increase proinflammatory functions of alveolar immune cells. Thus, anti-inflammatory agents that do not further suppress antimicrobial functions are required. We tested the hypothesis that intraoperative prostaglandin E1 (PGE1) suppresses proinflammatory responses and prevents the reduction in antimicrobial responses of alveolar immune cells. DESIGN: Prospective, randomized, controlled, double-blind study. SETTING: University hospital. PATIENTS: A total of 40 patients undergoing elective orthopedic surgery under propofol/fentanyl anesthesia. INTERVENTION: In double-blind fashion, the patients received PGE1 from the beginning to the end of surgery (PGE1 group, n = 20) or nothing (control group, n = 20). METHODS AND MAIN RESULTS: Alveolar immune cells were harvested by bronchoalveolar lavage immediately after induction of anesthesia; 2, 4, and 6 hrs after induction of anesthesia; and at the end of surgery. We measured opsonized and nonopsonized phagocytosis. Microbicidal activity was evaluated to directly kill Listeria monocytogenes in alveolar macrophages. Finally, we determined the expression of proinflammatory cytokines including interleukin (IL)-1beta, IL-8, interferon-gamma, and tumor necrosis factor-alpha, and that of anti-inflammatory cytokines (IL-4 and IL-10) by semiquantitative polymerase chain reaction. Nonopsonized and opsonized phagocytosis and microbicidal activity of alveolar macrophages decreased and the expression of genes for all pro- and anti-inflammatory cytokines increased significantly over time in both groups. Starting 2-4 hrs after induction of anesthesia, the increases in gene expression of proinflammatory cytokines were 1.5-3 times smaller in the PGE1 than in the control group. Starting 6 hrs after anesthesia, the increase in gene expression of IL-10 was 1.5-3 times greater in the PGE1 than in the control group. Intraoperative decreases in phagocytic and microbial activities were the same in the two groups. CONCLUSION: Intraoperative PGE1 not only suppressed proinflammatory responses, but also protected antimicrobial functions of alveolar macrophages, possibly because PGE1 is mostly inactivated in the pulmonary intravascular space. Our results suggest that intraoperative PGE1 protects the pulmonary immune defense in alveolar immune cells. 相似文献
108.
109.
Elevated bradykinin and decreased carboxypeptidase R as a cause of hypotension during tryptophan column immunoabsorption therapy. 总被引:2,自引:0,他引:2
Tryptophan column immunoabsorption therapy is beneficial to the patient with a neuroimmunological disease, but some complications have been attributed to this treatment. There have been some instances of an abrupt shock state along with severe decreases in blood pressure. In regards to this shock state, it has been reported that plasma bradykinin levels increase during tryptophan column immunoabsorption therapy. In this study, we examined the correlation between plasma bradykinin levels and either blood pressure or the levels of its degrading enzymes, angiotensin converting enzyme (ACE) and carboxypeptidase R (CPR) in 6 patients. Increased concentrations of bradykinin were present in the latter half of the therapeutic interval, and plasma bradykinin levels were found to be inversely correlated to CPR activity. The decreased CPR level could augment the activities of bradykinin. We speculate that bradykinin could be responsible for the hypotension occurring in patients during tryptophan column immunoabsorption therapy and that the metabolism of bradykinin could be caused by the decreased activity of CPR. 相似文献
110.
Yoshiaki Takahashi Toshiharu Matsuura Koichiro Yoshimaru Yusuke Yanagi Makoto Hayashida Tomoaki Taguchi 《Journal of pediatric surgery》2018,53(11):2245-2249