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71.
72.
在免眼中进行经瞳孔阈值下温热疗法的组织学效应和蛋白表达 总被引:1,自引:0,他引:1
Yoshihiro Morimura Annabelle A. Okada Atsushi Hayashi Sayuri Fujioka Sumie Kawahara Tetsuo Hida 李扬 《美国医学会眼科杂志(中文版)》2005,17(3):185-186
目的:研究阈值下经瞳孔温热疗法(TTT)对视网膜组织学的效应。方法:对正常视网膜色素的兔眼进行TTT,通过1个810nm激光二极管产生直径为1.2mm能量为50mW的光斑,持续时间为15、30和60秒。4周后进行荧光血管造影并摘除眼球,通过电子显微镜和免疫组化染色来检查。 相似文献
73.
M Kusunoki Y Shoji Y Sakanoue H Yanagi S Fujita T Yamamura J Utsunomiya 《The Journal of surgical research》1991,51(4):293-296
The effect of gamma-aminobutyric acid (GABA) on the human internal anal sphincter was investigated. Cumulative applications of GABA produced concentration-dependent contractions (10(-8)-10(-5) M) of the isolated human sphincter. Pretreatment with bicuculline (GABAA antagonist) turned them to relaxation. Muscimol, a GABAA agonist, induced concentration-dependent contractions (10(-8)-10(-5) M); however, baclofen (GABAB agonist, 10(-8)-10(-5) M) promoted concentration-dependent relaxation of the strips. These results suggested that both excitatory GABAA receptors and inhibitory GABAB receptors exist in the internal anal sphincter. Oral administration of sodium valproate (1600 mg/day), a GABA transaminase inhibitor, enhanced the anal canal resting pressure in 10 normal volunteers. Anal manometry showed a significant elevation in tonus without affecting amplitudes or frequencies. These results indicated that endogenous GABA, which was increased by sodium valproate, produced elevations in the anal canal resting pressure through its specific receptors in the human internal anal sphincter. 相似文献
74.
75.
T Urakawa Y Nagahata S Fukuoka T Hayashi T Takata S Matsui M Nakamoto Y Hirai K Kumagai Y Saitoh 《Nihon Geka Gakkai zasshi》1986,87(2):180-188
We prepared obstructive jaundice models in rats in order to study the mechanism of acute ulceration in obstructive jaundice centering on impediments to gastric wall blood flow and changes in gastric mucosal NA and PGE2 when the rats were subjected to water immersion restraint stress. The results were: In the obstructive jaundice 2 weeks group, when subjected to water immersion restraint stress, gastric mucosal NA reached a dried up stage from the incipient stage, causing gastric mucosal impediments at the same time, showing a significant decrease of gastric mucosal PGE2. Intragastric pH was at a similar level of excessive acidity in all groups; gastric acid is believed to be a secondary factor promoting ulceration. Gastric mucosal PGE2 showed a significant decrease coinciding with the increase in ulceration index, being a possible factor of ulceration; it is also presumed to regulate gastric wall blood flow alternatively with gastric mucosal NA. Pre-treatment with PGE2 prior to loading stress resulted in a decrease in gastric wall blood flow being significantly controlled. The administration of PGE2 brought about an improvement in gastric wall blood flow and a consequent increase in gastric mucosal NA, being judged effective for acute ulceration in obstructive jaundice. 相似文献
76.
S Ueno R Ootsuka Y Hayashi H Nishitani N Shirakawa T Hashimoto 《Nihon Igaku Hōshasen Gakkai zasshi. Nippon acta radiologica》1992,52(10):1417-1423
Intracranial MR imaging was performed in five patients with achondroplasia. All patients had narrowing of the subarachnoid space at the level of the foramen magnum that was mainly due to protrusion of the posterior aspect. Three patients had compressive deformities of the brainstem and/or upper cervical spine. Among them, two patients had deformities of the pons. Relative upward displacement of the brainstem was seen in all patients. Hydrocephalus was seen in three patients. 相似文献
77.
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
78.
Spermidine/Spermine N-Acetyltransferase, a New Biochemical Marker for Epithelial Proliferation in Rat Bladder 总被引:4,自引:4,他引:0
Isao Matsui-Yuasa Shuzo Otani Yoshihisa Yano Nobuyasu Takada Masa-Aki Shibata Shoji Fukushima 《Cancer science》1992,83(10):1037-1040
We examined the activity of spermidine/spermine N 1 -acetyltransferase (SAT), a rate-limiting enzyme of the biodegradation of polyamines, in N -butyl- N -(4–hydroxybutyI)nitrosamine-induced transitional cell carcinoma (TCC) and melamine-induced papillomatosis of rat bladder, and compared the activity to that of ornithine decarboxylase (ODC). Both activities were higher in both lesions than in control rats. The difference between SAT and ODC activities in cancerous tissue and papillomatosis was not significant. Cells stained for proliferating cell nuclear antigen (PCNA) were abundant in papillomatosis. TCC had areas with much PCNA. The results indicated that an elevation of SAT activity occurs in both reversible and irreversible proliferation of bladder epithelium and could be important in bladder carcinogenesis. 相似文献
79.
We performed a chromosome analysis of 26 pediatric brain tumors, including 20 primitive neuroectodermal tumors (PNETs), 5 astrocytomas, and I immature teratoma. Specimens were treated with collagenase, placed in overnight or short-term cultures, and harvested for chromosome analysis. Numerical and/or structural abnormalities were noted in 14 of the 20 PNETs and 4 of the 5 astrocytomas. In 13 PNETs, so-called medulloblastoma in the cerebellum, an i(17q) was the most frequent structural abnormality, accounting for 30% (4/13). Double minute chromosomes (dmin) were observed in one tumor. Near-diploidy was demonstrated in three of these PNETs, hyperdiploidy in three, and near-tetraploidy in three. We could not find any correlation of these cytogenetic findings with the prognosis. In the remaining seven PNETs other than medulloblastoma, the karyotypes of five PNETs demonstrated a variety of numerical and structural abnormalities. As to the astrocytomas, losses of chromosomes 7 and 9 with dmin were observed in two, and structural abnormalities of chromosomes 1 and 17 were also observed in two tumors. In our limited cases, however, we could not find the same chromosome abnormalities that are well known in adult astrocytomas. A congenital immature teratoma showed hyperdiploidy with increased numbers of chromosomes 3, 6, and 12. We conclude that i(17q) is an important chromosome abnormality in medulloblastomas, and that the oncogenesis of pediatric astrocytomas might be different cytogenetically from that of adult astrocytomas. 相似文献
80.
M. Ito K. Hayashi Y. Ishida M. Uetani M. Yamada M. Ohki T. Nakamura 《Calcified tissue international》1997,60(1):11-15
For several different bone mineral measurements and various skeletal sites, we compared capability to discriminate between
women in various age decades with and without spinal fracture, and attempted to identify the most effective cutoff level in
discrimination of spinal fracture. The subjects were 88 women aged 50–59 years (including 32 with fracture), 95 women aged
60–69 years (including 54 with fracture), and 34 women aged 70–79 years (including 18 with fracture). Spinal trabecular and
cortical bone mineral density (BMD) were measured using quantitative computed tomography (CT), and spinal, radial (ultra-distal,
10% distal and 33% distal), and calcaneal BMD were measured by dual X-ray absorptiometry. These BMD values were obtained in
each subject on the same day. Three statistical techniques—Student's t-test, the logistic regression analysis, and the receiver operating characteristics (ROC) analysis— were applied and accuracy
was calculated using the various cutoff values. The capability to discriminate between women with and those without fracture
using these BMD values was different among the three age groups. In women aged 50–59 and 60–69 years, all measurements showed
good capabilities for discriminating women with fracture. In women aged 70–79 years, these measurements showed lower capability
than in those aged 50–59 and 60–69 years, but among them, the calcaneal and ultradistal radial BMD showed relatively good
capability. The 10% and 33% distal radial BMD values were not useful in the detection of the high risk women with fracture.
The cutoff BMD values for discrimination of women with fracture varied according to the sites and methods of measurement.
For each specific age group, the most suitable measurement methods and the appropriate skeletal sites should be considered,
and the effective cutoff values to discriminate those with fracture may differ according to the measurement methods, the skeletal
sites examined, and age.
Received: 5 February 1996 / Accepted: 18 June 1996 相似文献