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991.
992.
The thymus of the teleost fish Oryzias latipes is a paired structure found at the dorsoposterior part of the gill chamber. In 3-month-old fish, the thymus shows a great development. The thymus displays atrophy during aging, and the thymus involution continues until 5 years of age. Male thymus shows heavier involution than female thymus of the same age. Emigration of thymus cells takes place at all ages but increases with age.  相似文献   
993.
In a typical case of chronic myelomonocytic leukemia (CMML), a chromosome abnormality, 46,XY,20q-, was observed in all the dividing cells including up to 16-ploid cells in the bone marrow and the blood. As the mitotic figures could be easily seen not only in myelomonocytoid cells but also in erythroblasts in the bone marrow smear, it was concluded that all the cell lineages except lymphocytes had the abnormality. The present case will support the view that the leukemic process in CMML affects a multipotent stem cell rather than a granulocyte-monocyte committed stem cell.  相似文献   
994.
995.
996.
Sweating function and retinal arterial reactivity in patients with migraine were examined during headache-free intervals. The sweat glands were stimulated by intradermal injection of pilocarpine hydrochloride, and molds of sweat droplets were obtained using Silastic. The number of droplets in classic migraine was significantly lower than that in the controls. The retinal arterial response to changes in perfusion pressure was measured by means of a fundus camera. The retinal vasomotor index (-change in retinal arterial diameter (%)/change in effective MABP (mmHg)) was significantly lower in classic and in common migraine than in controls. The above results suggest that sweating function and retinal arterial reactivity are impaired in patients with migraine and that the impairment may play an important role in the pathophysiology of migraine attacks.  相似文献   
997.
998.
999.
The biodistribution and in vivo kinetics of [131I]lipiodol infused into the hepatic artery were studied to estimate the potential of internal radiotherapy of hepatic cancer in five patients. It accumulated only in the vascular tumors and adjacent hepatic tissue (AHT) supplied by the infused artery, and to a lesser extent in the lung throughout 8 days imaging sequence. Iodine-131 lipiodol appeared to lead to oil embolization of the tumor and AHT followed by secondary embolization to the lungs and finally the activity was mainly excreted into urine. Four tumors had rapidly and slowly decreasing components, while the AHT activity decreased exponentially from the beginning. The effective half life in tumors was longer with the slow component (mean +/- s.d.: 5.7 +/- 1.2 days) than the AHT (3.7 +/- 0.6 days). The tumor/AHT concentration ratio in three patients at 2 hr was estimated to be 7.5-21. The activity was lower in the lungs than in the AHT in four patients. Iodine-131 lipiodol thus may be used as an intra-arterial infusion agent to treat certain vascular hepatic cancers.  相似文献   
1000.
To investigate the possibility of flow cytometric BrdU/DNA assay as a rapid chemosensitivity test, preliminary studies were performed utilizing CDDP-sensitive and CDDP-resistant mouse leukemic L1210 cell lines. The results indicated that the anticancer effects of CDDP to these cells could be rapidly determined by analyzing the effects on cell kinetics and the effects on BrdU uptake with this method. Also, this method could detect CDDP-resistant cells at proportion approaching 0.1% in a predominantly CDDP-sensitive population. In the near future, this flow cytometric method could be utilized not only as a useful screening test for anticancer drugs for initial cancer chemotherapy but also as a monitoring test to rapidly detect drug-resistant cells and thereby aid in the selection of a more effective anticancer therapy.  相似文献   
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