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81.
82.
Radioaerosol inhalation lung imaging using technegas 总被引:1,自引:0,他引:1
T Isawa T Teshima Y Anazawa M Miki M Motomiya 《Kaku igaku. The Japanese journal of nuclear medicine》1990,27(11):1273-1280
Technegas generator using 99mTc-pertechnetate was tested on 4 normal subjects and 31 patients with various chest diseases including bronchogenic carcinoma, pneumonia, pulmonary tuberculosis, sarcoidosis, and so on. Technegas was inhaled from the RV to the TLC levels through the mouth with the nose clipped followed by breath-holding. Three deep breaths were enough to deposit 37-55.5 MBq (1 to 1.5 mCi) of technegas in the lungs. The average alveolar deposition ratio (ALDR) was 85% and penetration of inhaled technegas to the lung periphery was excellent. "Hot spots" or excessive radioactive deposition were also seen when there was airway obstruction. The former indicated the characteristic as gas and the latter, that as aerosol particles. Because of the large ALDR's the timing for imaging lungs after inhalation of technegas most likely indicated the intrapulmonary sites of effective ventilation, because respective inhalation and perfusion lung images resembled each other very much. The disadvantage of technegas was that it was anoxic right after generation. 相似文献
83.
Nomizu T Tsuchiya A Kanno M Katagata N Watanabe F Yamaki Y Abe R Miki Y 《Breast cancer (Tokyo, Japan)》1997,4(4):239-242
The possible role of germline mutations ofBRCA1 andBRCA2 as causative agents of familial breast cancer was assessed. Their possible involvement in the carcinogenesis of hereditary
breast cancer was investigated using 63 clinically suspect families. Twenty-one lineages (33.3%) had mutations in one of the
twoBRCA genes. This relatively low incidence suggested that germline mutations in unknown genes are involved in the carcinogenesis
of hereditary breast cancer in the Japanese population. However, the clinicopathological features characteristic of hereditary
breast cancer, such as early disease onset, a high incidence of bilateral breast cancer, and a high incidence of multiple
primary carcinomas in other organs were confirmed in the present study. 相似文献
84.
Kunihiko Shiraki Mitsuyasu Moriwaki Muneaki Matsumoto Takeya Khono Tokuhiko Miki 《International ophthalmology》1997,21(1):43-50
Purpose. Hypofluorescent spots were seen inindocyanine green (ICG) angiography of peau dorangefundus in eyes with angioid streaks. Origin of the hypofluorescentspots were examined with attention to their correlationwith a peau dorange appearance of the central fundususing a computer-assisted image comparison system. Methods. ICG angiography was performed in 5 patientshaving peau dorange appearance of fundus using ascanning laser ophthalmoscope (SLO) and a digitalvideo-fundus camera. The same central fundus areas corresponding to hypofluorescent spots in an ICGangiogram were then digitally identified in afluorescein angiogram and in a red-free picture in all10 eyes of the 5 patients. Monochromatic lightobservation was also performed with a dark fieldobservation using a SLO to see subretinal orintrachoroidal pigment clumping. Results. In no patient, the areas identified withhypofluorescent spots did show relevant changes ina fluorescein angiogram or a red-free picture. SLOexamination revealed not perfusion defect at the sameareas. The dark field observation showed no pigmentclumping at the peripapillary and papillomacularbundle regions where hypofluorescent spots were seen.Conclusions: Hypofluorescent spots seen in ICGangiograms did not show exact consistency with peau dorange changes in their location and shape. Perfusion defects or blocking by pigments were not acause of hypofluorescent spots. The scatteredhypofluorescent spots were considered to be relevantwith irregular affinity of the fundus to ICG dye. 相似文献
85.
Approximately 10-30% of the Japanese population suffer from Japanese cedar (Cryptomeria japonica) pollinosis in the spring. To date, the effects of this pollinosis on lymphocyte subpopulations have not been examined epidemiologically. To examine the effects of smoking and Japanese cedar pollinosis on lymphocyte subpopulations, we used flow cytometry to measure CD4+ and CD8+ T-lymphocyte subpopulations, natural-killer cell subpopulations, B(CD19+) lymphocytes, and total lymphocytes in 61 smokers and 51 nonsmokers. Some of these individuals had histories of pollinosis during November 1993-an off-season for Japanese cedar pollination. Our findings suggested that (a) CD4+ T-lymphocyte subpopulations (i.e., CD4+CD29+, CD4+CD45RA+, and CD4+ CD45RO+ cells) together with total CD4+ T, total T, and total lymphocytes, were increased by the effects of smoking; (b) CD8dim+CD11a+T, and CD8+CD11bt, and CD57+CD16+ natural killer cells, together with total CD8+CD11 a+ T and total CD8+ T lymphocytes, were increased by the effects of pollinosis on smokers, even though no lymphocyte subpopulations were increased by only the pollinosis effects; (c) CD4+CD29+T and CD8dimCD11a+ T lymphocytes were increased by the effects of smoking on pollinosis, and (d) CD4+CD29+ T and CD4+CD45RO+ T lymphocytes, CD8dim+CD11 a+ T, and CD8+CD11b+ T lymphocytes and CD57+CD16+ natural killer cells, together with total CD4+ T, total T (CD3+), total CD8+CD11a+, total CD8+ T, and total lymphocytes, were increased by the combined effects of smoking and pollinosis. 相似文献
86.
We investigated age-related changes in the visibility of intracranial arteries on magnetic resonance angiography (MRA) and
the influence of risk factors for stroke. We studied 230 adult patients without specific neurological deficits. MRA was performed
using the three-dimensional time-of-flight technique with a spoiled gradient-recalled acquisition sequence. We classified
internal carotid artery (IC) and the horizontal (M1) and distal (beyond M2) middle cerebral segments into 4 grades. Linear
regression revealed a significant negative relation between age and the quality of demonstration on MRA. For IC and M1, the
score was significantly lower in subjects with risk factors than in those without. The distal MCA was poorly seen in patients
without a history of hypertension or lacunar infarcts. A marked correlation was observed between visibility and age patients
with no history of hypertension, diabetes mellitus and hyperlipidaemia. We suggest that atherosclerotic change and decline
in flow velocity with normal ageing are factors leading to decreased visibility on MRA.
Received: 13 January 1998 Accepted: 6 January 1999 相似文献
87.
Rapid progression of pituitary hyperplasia in humans with primary hypothyroidism: demonstration with MR imaging. 总被引:5,自引:0,他引:5
T Shimono H Hatabu K Kasagi Y Miki S Nishizawa T Misaki A Hiraga J Konishi 《Radiology》1999,213(2):383-388
PURPOSE: To use magnetic resonance (MR) imaging to evaluate the morphologic changes of the pituitary gland during the development of hypothyroidism. MATERIALS AND METHODS: Fourteen patients who had undergone thyroidectomy were evaluated before radioactive iodine 131 therapy. In each patient, MR imaging and measurement of serum hormone levels were performed twice: 5 weeks before 131I treatment as the "euthyroid state" with thyroid hormone supplementation and on the day of 131I treatment as the "hypothyroid state" after a 3-week depletion of thyroid hormone supplements. Nine healthy volunteers also underwent MR imaging twice at an interval of 5 weeks. Pituitary volume and the relative signal intensity ratio of the anterior pituitary to the pons were measured. The shape and signal intensity of the pituitary gland were also visually assessed. The paired Student t test was used to evaluate the significance of the data. A P value less than .05 indicated a statistically significant difference. RESULTS: The patients had significantly larger pituitary volume in the hypothyroid state than in the euthyroid state both quantitatively (P < .001) and visually. No significant differences were found in the relative signal intensity ratios of the anterior pituitary to the pons. In healthy volunteers, no significant differences in pituitary volumes or signal intensity were found between the two MR images. CONCLUSION: Rapid progression of hyperplasia of the anterior pituitary may occur with acute development of hypothyroidism. 相似文献
88.
Greenleaf JE Shiraki K Sagawa S Miki K Wada F Nagaya K Torii R Keil LC 《Aviation, space, and environmental medicine》1999,70(12):1201-1205
BACKGROUND: This study examines the relationship between the threshold for plasma vasopressin concentration [PVP] responses and diuresis (Gauer-Henry reflex), and tests the hypothesis that water intake would not influence diuresis. METHODS: Eight men (19-25 yr) underwent four treatments: euhydration in air (Eu-air), euhydration in water immersion (Eu-H2O), and with prior 3.6% hypohydration in air (Hypo-air), and hypohydration in immersion (Hypo-H2O). Ad libitum drinking was allowed during the 3-h experimental and 1-h recovery periods. RESULTS: Drinking was greatest during the first 10 min: 3.5 ml x kg(-1) with Hypo-air (450 ml x 3 h(-1)) and only 1.7 ml x kg(-1) (p < 0.05) with Hypo-H2O (235 ml x 3 h(-1)). At 1 h, concomitant [PVP] decreased from a control level of 6.6+/-1.5 to 4.0+/-1 .0 pg x ml(-1) (delta = 2.6 pg x ml(-1), p < 0.05) with Hypo-air, and from 5.9+/-0.6 to 2.3+/-0.2 pg x ml(-1) (delta = 3.6 pg x ml(-1), p < 0.05) with Hypo-H2O. Urine flow was unchanged from control level (<1.0 ml x min(-1)) with Hypo-air, Hypo-H2O, and Eu-air, but increased to 4-5 ml x min(-1) with Eu-H2O. Neither water intake volume nor urine flow was related to the magnitude of [PVP] depression. Regression of Uosm/Posm ratio on [PVP] and urine flow indicated that [PVP] above 2 pg x ml(-1) did not affect urine flow. Thus, ad libitum water intake in previously hypohydrated subjects did not affect urine flow or the decrease in [PVP]. The threshold [PVP] to initiate significant diuresis was about 2 pg x ml(-1), and significant diuresis can occur with no change in [PVP] maintained at about 1 pg x ml(-1) during immersion in euhydrated subjects. CONCLUSIONS: Thus, it appears that the Gauer-Henry reflex is not the major mechanism for immersion-induced diuresis. Clearly, other diuretic factors are also involved. 相似文献
89.
90.
Nakanishi H Nakao M Nomoto T Miki T Nakagawa S Kitamura K Watanabe H 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1999,90(11):853-858
BACKGROUND: The objective of this study is to determine age-specific PSA reference ranges in Japanese healthy men and investigate the effectiveness of these ranges as the cut-off values in the mas screening for prostatic cancer. METHODS: The study included a total of 5,206 male aged from 55 to 89 years old who wished to submit the mass screening for prostatic cancer in an urban area of Kyoto in 1995-1997, but had no evident prostatic cancer. We measured serum PSA levels by the filter paper method (Delfia PSA kit). RESULTS: We found the increase in serum PSA levels with the advancing age. With the 95th percentile for serum PSA as the upper limit, the age-specific PSA reference ranges were determined to be 2.1 ng/ml for patients aged 55 to 59 years old, 3.2 ng/ml for 60 to 69 years old, 4.4 ng/ml for 70 to 79 years old, 6.5 ng/ml for 80 to 89 years old. If we used these ranges as the cut-off values in the mass screening this time, five cases from 76 to 89 years old of prostatic cancer were overlooked. CONCLUSIONS: We found the increase in serum PSA levels with advancing age. But the positive proof of using this range to a mass screening for prostatic cancer was not certified, because time incidence of prostatic cancer in the examinees was uncertain and there is a possibility of overlooking some cases. 相似文献