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排序方式: 共有5807条查询结果,搜索用时 15 毫秒
1.
Nobuaki Yanagisawa Shinichi Abe Hiroko Agematsu Koji Sakiyama Akinobu Usami Yuichi Tamatsu Yoshinobu Ide 《Annals of anatomy》2006,188(4):329-336
To elucidate the effects of teeth on muscle fibers in the tongue during the developmental process, we examined the expression of muscle contractile proteins and the genes for those proteins in normal mice and microphthalmic (mi/mi) mice with impaired tooth eruption. The mice were observed during the growth period, including weaning, which is when feeding movements undergo major changes. Expression of the myosin heavy chain (MyHC)-2a protein, whose contraction speed is relatively slow, disappeared after weaning in normal mice, while it remained in high concentrations even after weaning in mi/mi mice. The presence of MyHC-2a after weaning in mice with no tooth eruption was attributed to a compensation for lack of proper masticatory function and sucking-like movements, as MyHC-2a is necessary for these movements. 相似文献
2.
The ion recombination loss is one of the most important correction factors for dosimetry using ionization chamber especially for the measurement of high-intensity pulsed radiation beam. The two-voltage method has been used frequently for the correction of ion recombination loss. Several ways to approximate the method are presented. Comparisons were carried out to check the validity of the approximation. Using four ionization chambers of different types and shapes, measurements were made to obtain the optimal value of the ratio for the two voltages. 相似文献
3.
Nobuaki Miyazono M.D. Hiroki Inoue Akira Hori Ichiroh Kanetsuki Jurio Shimada Masayuki Nakajo 《Cardiovascular and interventional radiology》1994,17(1):36-37
We present a 44-year-old woman in whom a bronchialto-coronary artery communication via the conus branch was discovered after distal bronchial artery embolization with gelatin sponge for hemoptysis. If this bronchial-to-coronary artery anastomosis, not visible prior to embolization, had been inadvertently embolized, the patient could have developed a myocardial infarction. To reduce the likelihood of a serious complication, the possibility of this anastomosis should be kept in mind and angiography should be repeated before attempting proximal bronchial artery embolization. 相似文献
4.
Michihiko Fukui Maho Imoto Nobuaki Shime Tetsuo Hatanaka Hideaki Tojo 《Journal of anesthesia》1997,11(1):27-31
We developed a continuous oxygen consumption (Vo2) measurement system employed the reversed Fick method, in which Vo2 in computed from continuously measured sured arterial and mixed venous oxygen saturation assed by pulse oximetry and mixed
venous oximetry, respectively, and cardiac output by the heat deprivation technique. This system was compared with the conventional
intermittent reversed fick method in 7 patients during surgery and with indirect calorimetry in 4 intensive care unit (ICU)
patients. The Vo2 measured by the continuous reversed Fick method showed a high correlation with those simultaneously measured by the intermittent
Fick method (r=0.97,P<0.01) and by indirect calorimetry (r=0.74,P<0.01). The 95% confidence limits (bias±2 SD) of the continuous reversed Fick method were −0.6±45 ml·min−1 with the intermittent Fick method and −31±56 ml·min−1 with indirect calorimetry. The continuous Fick method is in satisfactory agreement with the conventional methods for the
measured of Vo2 and potentially allows for convenient assessment of Vo2 in critically ill patients.
This study was supported in part by Grants-in-Aid for the Encouragement of Young Scientists 01771185 and 04857171 from the
Ministry of Education, Science and Culture of Japan 相似文献
5.
6.
Expression of cell-matrix molecules and integrin receptors in human liver grafts during chronic rejection 总被引:1,自引:0,他引:1
Ken Hoshino Bjorn Nashan Gustav Steinhoff Rudolf Pichlmayr K. Hoshino 《Transplant international》1994,7(S1):637-640
Abstract The inflammatory response of immune cells to target cells and cell-matrix molecules is regulated by several receptor-ligand molecules. As fibrosis develops in ongoing chronic rejection after liver transplantation, it is of interest to analyze patterns of integrin receptors and cell-matrix molecules in order to study the relation between immune cells and the stromal and parenchymal cells. In the present study, we demonstrated the expression of these molecules in chronic rejected human liver grafts using immunohistochemical techniques. The results showed a differential expression and induction of integrin receptors and cell-matrix molecules on resident liver cells, especially on sinusoids, reflecting a state of chronic inflammation and a specific interaction between integrin receptors and cell-matrix molecules. The patterns of induced integrin receptors on graft-infiltrating cells was closely related to the local production of cell-matrix molecules and reflected the final sequence of a stepwise progress of the inflammatory reaction. 相似文献
7.
Contraction of the longitudinal smooth muscle of the isolated guinea pig oviduct in response to autacoids was examined at different phases of the sex cycle or during ovarian steroid treatments. Isolated strips from isthmic smooth muscle of the female guinea pig (body weight; 300-900 g) oviduct were mounted in an organ bath and their isotonic responses were measured in the longitudinal direction. Histamine (greater than or equal to 3 X 10(-8) M) produced a concentration-dependent contraction of the oviductal smooth muscle, which was unaffected by the sex cycle. Noradrenaline and adrenaline (greater than or equal to 10(-8) M) produced a contraction mediated by alpha-adrenoceptors and a relaxation mediated by beta-adrenoceptor. During proestrus and metestrus (high estrogen), the contractile response was reduced but relaxation was increased, compared with those observed during diestrus. Prostaglandin E2 and F2 alpha (greater than or equal to 10(-10)M and greater than or equal to 10(-9)M, respectively) produced a concentration-dependent contraction and their maximum responses were about 50% of that induced by histamine (10(-4)M). These contractile responses were unaffected by the sex cycle. On the other hand, acetylcholine did not modify the smooth muscle tone of the isolated guinea pig oviduct in the concentration range from 10(-7)M to 3 X 10(-4)M. The contractile response of the oviductal smooth muscle to adrenaline after bilateral ovariectomy was inhibited by estrogen treatment, while relaxation was inhibited by progesterone treatment. 相似文献
8.
9.
T Hoshino L A Rodriguez K G Cho K S Lee C B Wilson M S Edwards V A Levin R L Davis 《Journal of neurosurgery》1988,69(6):839-842
The proliferative potential of low-grade astrocytomas was estimated in 47 patients. Each patient received an intravenous infusion of bromodeoxyuridine (BUdR), 150 to 200 mg/sq m, at the time of craniotomy to label cells in deoxyribonucleic acid (DNA) synthesis; the percentage of S-phase cells, or BUdR labeling index (LI), of each tumor was determined immunohistochemically. In 29 patients (60%), the tumors had BUdR LI's of less than 1%, indicating a slow growth rate; only three (10%) of these patients died of recurrent tumor during a follow-up period of up to 3 1/2 years. In contrast, of the 18 patients (40%) whose tumors had BUdR LI's of 1% or more, 12 (67%) had a recurrence and nine died during the same follow-up period. These results show that the proliferative potential, as reflected by the BUdR LI, is an important prognostic factor that separates low-grade astrocytomas into two groups and provides a more scientific rationale for selecting treatment for individual patients. 相似文献
10.
Acute effect of thyroid hormone on insulin secretion in rats 总被引:1,自引:0,他引:1
T Ikeda K Fujiyama T Hoshino Y Tanaka T Takeuchi H Mashiba M Tominaga 《Biochemical pharmacology》1990,40(8):1769-1771
To elucidate the mechanism of thyroid hormone-induced hyperinsulinemia, the acute and direct effect of thyroid hormone administration on insulin secretion was investigated in rats in vivo and in vitro. In the perfused rat pancreas, the addition of thyroxine (10 micrograms/dL) or 3,5,3'-triiodothyronine (150 ng/dL) to the perfusing medium did not affect insulin secretion. The administration of thyroxine (40 micrograms/kg, s.c.) in vivo increased the plasma insulin level from 11 +/- 2 microUnits/mL (mean +/- SD) to 30 +/- 7 microUnits/mL, while blood glucose and plasma glucagon were unchanged. This phenomenon was inhibited completely by the preadministration of oxprenolol hydrochloride (2 mg/kg, s.c.), and inhibited partly by the preadministration of metoprolol tartrate (35 mg/kg, s.c.). These results suggest that thyroid hormone induces hyperinsulinemia via beta-adrenergic stimulation in the rat. 相似文献