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81.
82.
Although iodine prevents goiter, enlarged thyroid glands continue to be detected in subjects, especially children, in spite of adequate iodine ingestion. Iodine may cause goiter in susceptible individuals by inhibiting the organic binding of iodine as is seen in adult asthmatics, neonates born of iodine ingesting mothers and in subjects residing along the littoral of Japan. Myxedema, especially in treated Graves' disease and Hashimoto's disease, may also be precipitated by iodine. On the other hand, iodine given to euthyroid subjects in areas of endemic goiter and to subjects with nontoxic nodular goiter may induce thyrotoxicosis by disclosing diffuse autonomously functioning thyroid tissue. An indirect adverse effect of iodine upon the thyroid gland may be manifested by lymphocyte glandular infiltrates and chronic thyroiditis which were sparse or absent in thyroid glands removed from subjects living in iodine deficient areas before iodine prophylaxis and therapy. Not only has the incidence of thyroiditis increased, but the histologic and clinical distinctions between treated Graves' disease and chronic thyroiditis have become indistinct. Experimentally, chronic thyroiditis has been produced in animals following large doses of iodine. Accumulated evidence supports the concept that iodine contributes to the genesis of chronic thyroiditis. 相似文献
83.
Knoll G. F. Lieberman L. M. Nishiyama H. Beierwaltes W. H. 《IEEE transactions on nuclear science》1972,19(1):76-80
A specially designed scintillation probe has been assembled and applied in a promising diagnostic study of malignant melanoma in the human eye. When used in conjunction with a new radiopharmaceutical agent recently developed at The University of Michigan, 125I labeled chloroquine analog, the probe permits simple and nonsurgical gamma ray counting as a substitute for more elaborate techniques required in 32p beta scanning for the same prupose. Preferential uptake of the agent in ocular melanomas has been previously reported using a modified 5-inch NaI (Tl) crystal scanner as the detector. We have realized a substantial improvement in both sensitivity and reproducibility by substituting a hand-held probe placed in contact with the patient's closed eyelid. The counting rate over each eye is followed for a period ranging from 3 to 21 days after dosage. A melanoma in one eye gives rise to an enhanced rate over that eye. Data are presented on a total of 12 patients, including two with confirmed ocular melanomas. In both of these cases, the involved eye consistently shows a significantly greater activity than the opposite eye. In the remaining cases considered "negative", measured eye-to-eye asymmtries are much lower, and a measure of the variance associated with these cases is presented. 相似文献
84.
BACKGROUND: N-methyl-D-aspartate (NDMA) antagonists have minimal effects on acute nociception but block facilitated states of processing. In contrast, the alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) antagonists decrease acute noxious responses. Morphine (a mu-opioid agonist) can also decrease acute nociceptive processing. The authors hypothesized that the interaction between morphine and AMPA receptor antagonists would be synergistic, whereas morphine and NMDA antagonists show no such interaction in acute nociception. METHODS: Sprague-Dawley rats (weight, 250-300 g) were implanted with chronic lumbar intrathecal catheters and were assigned to receive one of several doses of morphine--ACEA 1021 (NMDA glycine site antagonist), ACEA 2085 (AMPA antagonist), AP-5 (NMDA antagonist), saline or vehicle--and were tested for their effect on the response latency using a 52.5 degrees C hot plate. The combinations of morphine and other agents also were tested. RESULTS: Intrathecal morphine (ED50:2 microg/95% confidence interval, 1-4 microg) and ACEA 2085 (6 ng/2-15 ng), but not AP-5 or ACEA 1021, yielded a dose-dependent increase in the thermal escape latency. A systematic isobolographic analysis was carried out between intrathecal morphine and ACEA 2085 using the ED50 dose ratio of 357:1. A potent synergy was observed with decreased side effects. Morphine dose-response curves were carried out for morphine and fixed doses of ACEA 1021 (12 microg) or AP-5 (10 microg). No synergistic interactions were noted. CONCLUSIONS: Spinal mu-receptor activation and AMPA receptor antagonism showed a synergistic antinociception in response to an acute thermal stimulus. NMDA or NMDA glycine site antagonism had no effect alone nor did they display synergy with morphine. These results suggest an important direction for development of acute pain strategies may focus on the AMPA receptor. 相似文献
85.
To establish cheese as a dairy product with health benefits, we examined the multifunctional role of cheeses. In this report, we clarify whether different types of commercial cheeses may possess antiproliferative activity using HL-60 human promyelocytic leukemia cell lines as a cancer model. Among 12 cheese extracts tested, 6 (Montagnard, Pont-l’Eveque, Brie, Camembert, Danablue, and Blue) revealed strong growth inhibition activity and induction of DNA fragmentation in HL-60 cells. Based on the quantification of nitrogen contents in different cheese samples, a positive correlation between the ripeness of various cheeses and their antiproliferative activity tested in HL-60 cells was displayed. Four varieties of Blue cheese ripened for 0, 1, 2, or 3 mo demonstrated that the Blue cheese ripened for a long term was capable of causing the strong suppression of the cell growth and the induction of apoptotic DNA damage as well as nucleic morphological change in HL-60 cells. Collectively, these results obtained suggest a potential role of highly ripened cheeses in the prevention of leukemic cell proliferation. 相似文献
86.
In wet granulation processes, a particle adhesion mediated by a liquid bridge is one of the quite important phenomena. In an actual process, the liquid bridge shows dynamic motion due to continuous motion of the particles. Therefore, understanding of the particle adhesion phenomenon by a dynamic liquid bridge is essential to adequately and precisely control wet granulation processes. This study presents a direct numerical simulation of the particle–particle adhesion by a dynamic liquid bridge. Collision of a dry particle and a wet particle was simulated at various collision angles. In particular, translational and rotational motions of the particle at different collision angles were discussed through comparison with a conventional static liquid bridge force model. As a result, it was found that both translational and rotational motions were largely different between simulation results of the direct numerical simulation and static liquid bridge force model, especially at the tangential collision. To understand these results, we focused on the rotational behavior of the particle and deformation of the liquid bridge. It was concluded that the non-slip behavior of the liquid bridge on the particle surface is a key phenomenon for the particle-particle adhesion by the dynamic liquid bridge at the tangential collision. 相似文献
87.
The effect on evaporation rates of air content in flashing water was investigated experimentally in a scaled-down open-channel flash evaporator. The water was at 97°C–98°C, the flash-down temperature differences were up to about 2°C, and air content was up to 6.32 ppm. The ratio (ΔTs/Rc), of the local liquid superheat to the equilibrium radius of bubbles was proposed as the correlating parameter for the flash-evaporation heat transfer Stanton Number, and a correlation was developed. The presence of air in the water was found to have an important influence on the process: both the Stanton Number and the approach to equilibrium of the flashing water were seen to improve with air concentration. 相似文献
88.
Photodynamic thermoresponsive nanocarbon-polymer gel hybrids 总被引:1,自引:0,他引:1
Miyako E Nagata H Hirano K Hirotsu T 《Small (Weinheim an der Bergstrasse, Germany)》2008,4(10):1711-1715
89.
90.
Hsu HC Kikuchi H Yen SK Nishiyama M 《Journal of materials science. Materials in medicine》2007,18(4):605-609
The properties of several different investments were investigated including phosphate bonded, magnesia bonded, and alumina
cement investments. Measurements included the setting expansion, thermal expansion, and compressive strength of investments,
as well as the tensile strength, elongation, Vickers hardness (VHN) and surface roughness of titanium castings. For phosphate
bonded investment, the setting expansion after being mixed with its own mixing solution was 2.10%, which was larger than the
other investments; the thermal expansion was −0.25% at 200°C, the compressive strength 14 and 5 MPa after heating. For titanium
cast in phosphate bonded investment, the hardness on its top surface was 655 Hv, the tensile strength was 379 MPa, the elongation
was 19.4%, and the surface roughness was 2.29 μm. Athough the thermal expansion of phosphate bonded investment is small, the setting expansion is large enough to compensate
for the shrinkage of titanium castings. As its thermal expansion at T ≥ 600°C was constant and its heating-cooling cycle was almost reversible, these two properties can reduce the thermal shock
and thus avoid cracking of the investment. 相似文献