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Repeated injections of 45 ng/kg of maitotoxin into the peritoneal cavities of male ICR mice resulted in marked atrophy of lymphoid tissues, a reduction of lymphocytes in the circulating blood, reduced immunoglobulin M in serum, and an increase of calcium content in the adrenal glands. A single injection of 200 ng/kg of maitotoxin induced a marked increase in total calcium content of the adrenal glands as well as in plasma cortisol concentration (about seven times control) within 1 hr. In contrast, mice pretreated with CoCl2, a calcium channel inhibitor, and/or adrenalectomized mice, showed no discernible changes in the lymphoid tissues after repeated injections of maitotoxin. It is thus suggested that maitotoxin first stimulates calcium influx in the adrenal glands, which then causes the release of cortisol into the blood. The excess amount of cortisol in serum produces acute involution of the thymus and other lymphoid tissues. 相似文献
55.
Nobuo Takeichi Hisao Ito Rumi Haruta Toshiya Matsuyama Kiyohiko Dohi Eiichi Eiichi 《Cancer science》1991,82(1):19-22
The relationship between the histological grade of dedifferentiation of thyroid cancer and estrogen receptors (ER) was examined immunohistochemically. Thyroid cancers were from postmenopausal females of almost the same mean age (69-73 years old) and within the same period of time (1974–1983). ER immunoreactivity located in the nucleus of the epithelium was found in all 6 well differentiated papillary cancers, and 5 of them (83.3%) showed ER-immunoreactive (ER-IR) cells amounting to 20 or more per visual field (x 100) under a light microscope. Of the 6 cases of poorly differentiated papillary cancer, 5 (83.3%) had 1-19 ER-IR cells per visual field. ER-IR cells were negative in 5 out of 6 cases (83.3%) of anaplastic cancers. Thus, the number of ER-IR cells tended to decrease with the degree of atypism of thyroid cancer (P < 0.001). 相似文献
56.
Anatomical reconstruction of the thyroglossal duct 总被引:9,自引:0,他引:9
57.
Y Ito 《Fukushima journal of medical science》1989,35(1):1-12
With the view of making quantitative examination of the susceptibility of corneal epithelial cell and stromal cell to herpes simplex virus (HSV) infection, 6 HSV strains (4 of HSV type I, 2 of HSV type II) were inoculated in cultured rabbit's corneal cells (epithelial and stromal cells), and the following results were obtained: 1. When stock HSV was titrated with monolayer culture of each epithelial or stromal cells, strong CPE appeared within 24 hr in epithelial cell and the TCID50 titer of HSV was read as 10(7.5)-10(8.7)/ml at 120 hr. On the other hand, in stromal cell the TCID50 titer showed 10(6.4)-10(6.8)/ml at 72 hr and did not increase thereafter. 2. In terms of the growth curve for HSV type I, the eclipse period was about 4 hr for epithelial cell compared with about 4 hr for stromal cell. At 24 hr, postinfection of standard strain, about 10(7) TCID50/ml of virus was obtained from both epithelial and stromal cell culture. In the case of clinical isolate infection, however, about 10(7) TCID50 was obtained from epithelial cells and 1 in 10th lower titer of virus was obtained from stromal cells. The above results seemed to be of importance in the consideration of different onset mechanisms of epithelial type corneal herpes and stromal ones. 相似文献
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60.
M. Ito T. F. Lang M. Jergas M. Ohki M. Takada T. Nakamura K. Hayashi H. K. Genant 《Calcified tissue international》1997,61(2):123-128
This study examined trabecular bone mineral density (BMD) in Japanese women with and without spinal fracture, and compared
the results to American women with and without fracture. The quantitative computed tomography (QCT) systems used at the University
of California, San Francisco (UCSF) and at Nagasaki University were cross-calibrated. Normative BMD was assessed with the
K2HPO4 liquid phantom in 538 Americans aged 20–85 years, and with the B-MAS200 phantom in 577 Japanese aged 20–83 years. These BMD
were adjusted for use with the Image Analysis solid phantom using the result of cross-calibration. The trabecular BMD in 111
postmenopausal American women (55 with fracture), and in 185 postmenopausal Japanese women (67 with fracture) were compared
for investigation of the difference in BMD values relative to fracture status. The absolute BMD values in Japanese were lower
than those in Americans, and the differences were greater with advancing age. The magnitude of the BMD difference was 8.6,
20.5, 38.1 mg/cm3 in women aged 20–24 years, 40–44 years, 60–64 years, respectively. In premenopausal women, BMD began to decrease at the age
of 20 in Japanese, whereas the peak bone mass was maintained until the age of 35 in the American women. In immediate postmenopausal
women, BMD significantly decreased in both populations. In later postmenopausal women, BMD significantly decreased with age
in the Japanese women but decreased less rapidly in the American women. The aging decrease of BMD was 1.4% and 2.2% per year
in the later postmenopausal American and Japanese women, respectively. The fracture threshold is considered to be lower in
Japanese women. However, the BMD difference between American and Japanese women with fracture was similar to that without
fracture. The Z-scores of fracture subjects versus controls were 2.9 in American and 1.8 in Japanese women. In conclusion,
Japanese women were found to have a lower BMD and lower fracture threshold than American women. The significant decrease of
spinal trabecular BMD in late postmenopause is potentially responsible for the higher prevalence of spinal fracture in Japanese
women.
Received: 18 December 1995 / Accepted: 23 September 1996 相似文献