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111.
The aim of this study was to determine if 6-month acclimation would enable accurate evaluation of hematological, biochemical data, and ECG recorded under restraint for conscious rhesus monkeys of both sexes. Periodic evaluation of these parameters was made during the 6-month period of acclimation. The platelet count, alkaline phosphatase, glucose, and sodium levels significantly decreased, whereas creatinine increased, compared with pre-acclimation values. The heart rate was significantly reduced compared with pre-acclimation values. QT-RR relation followed the square root regression function, which means modification of Bazett's QTc formula can be applied even if the ECG is recorded under restraint. In conclusion, 6-month acclimation was effective for stabilizing the blood data and for allowing accurate evaluation of the ECG even under restraint. Current results show that an acclimation period at least 3 months may be necessary prior to using rhesus monkeys for chronic studies. 相似文献
112.
Takuma A Kaneda T Sato T Ninomiya S Kumegawa M Hakeda Y 《The Journal of biological chemistry》2003,278(45):44667-44674
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The changes in the levels of the binding protein for 5 alpha-dihydrotestosterone in cytoplasmic extract of the submandibular glands during development were compared in male and female mice using a DEAE-cellulose filter assay. The binding protein was first detectable 5 days after birth in both sexes, at a time coincident with androgen-independent cytodifferentiation of the convoluted tubular cells in the submadibular gland. The level of the binding protein in female mice was maintained at 5 pmol/mg protein after birth, whereas in males it began to decrease from 3 weeks after birth with inccrease in serum testosterone, becoming much less than a quarter of the level in females or immature mice by 4 weeks after birth. However, after castration, the level of detectable binding protein in mature male mice increased within 7 days to the same level as that in females or immature mice. This suggests that the low binding capacity for exogenous hormone in mature male mice is due to occupancy of the binding sites by endogenous hormone. 相似文献
115.
The actions of thyroxine, 5 alpha-dihydrotestosterone and hydrocortisone singly or in combination in enzyme regulation in the submandibular gland were studied in intact and adrenalectomized female mice. 1. Adrenalectomy decreased the activity of trypsin-like esteroprotease (EC 3.4.4.-), and administration of hydrocortisone to adrenalectomized mice restored the activity to normal. 2. Hydrocortisone and thyroxine had synergistic effects in induction of esteroprotease in adrenalectomized mice, but 5 alpha-dihydrotestosterone and hydrocortisone did not have synergistic effects in either intact or adrenalectomized mice. 3. The activity of glucose-6-phosphate dehydrogenase (EC 1.1.1.49) was not influenced by change in the glucocorticoid level, but was increased by thyroxine and 5 alpha-dihydrotestosterone in both adrenalectomized mice and intact mice.4. Isoelectric focusing in polyacrylamide gel showed that there are three distinct activities of esteroprotease in this gland with isoelectric points of 5.6, 6.2 and 7.3. Both thyroxine and 5 alpha-dihydrotestosterone similarly induced these activities and glucocorticoids did not affected the isozyme patterns induced by the other two hormones. 相似文献
116.
To gain further insight into the architecture of the gel network of some branched (1 → 3)-β-d-glucans, a 13C-n.m.r. study of sodium hydroxide-induced, conformational change was performed. The branched d-glucans examined were lentinan from Lentinusedodes, a lower-molecular-weight fraction thereof, and schizophyllan from Scilizophyllum commune; these (1 → 3)-β-d-glucans have two branches for every five d-glucopyranosyl residues (lentinan), or one for every three or four (schizophyllan) at 0-6. In contrast to the gel oflinear (1 → 3)-β-d-glucan (curdlan), all of the 13C signals due to the β-d-(1 → 3)-linked d-glucosyl residues were completely suppressed in the gel state. As the peak intensity and line width of the 13C-resonance peaks for the gel state are strongly influenced by the degree of cross-linking, such a complete loss of the peak areas can be explained in terms of a higher degree of cross-linking than that of the linear d-glucans. As demonstrated previously, the cross-links involve physical association of the helical segments, such as the double- or triple-stranded helices. These helix forms were found to be converted, at 0.2M sodium hydroxide, into the random-coil form (gel-to-sol transition), which gives rise to full peak-areas, because of complete breaking of the physical cross-links. Also, in contrast to the linear d-glucan, such helix-coil transition of the branched d-glucans proceeded in a noncooperative way: the peak intensity and line width gradually changed with the concentration of sodium hydroxide. This behavior is best interpreted in terms of distribution of the various degrees of cross-linking. Some loose cross-links are readily broken in the lower range of concentration of alkali (0.09M), and others are resistant until complete conversion into the random coil occurs (0.2M). This result is consistent with the view that the primary structure of the branched (1 → 3)-β-d-glucans is hi-highly branched, as in a tree-like structure. 相似文献
117.
Summary The development of trypsin-like esteroproteases in the submandibular gland of mice was studied, using a newly synthesized napthyl ester (tosyl-l-lysine -naphthyl ester) for the preparation of zymograms and for histochemical demonstration of the enzyme. Esteroprotease activities were first detected spectrophotometrically on day 15 after birth; then increased markedly after day 20. A sex difference in esteroprotease activity appeared on day 25. Zymograms prepared after isoelectric focusing in polyacrylamide slab gels showed that the glands of neonatal mice contained esteroproteases with a rather different composition from that of adult mice. The adult type isozymes appeared first on day 15, and their activities increased markedly after day 20. Histochemical studies revealed that the isozymes of neonatal mice were derived from mast cells. A few striated ducts were first stained on day 15, and the sex difference of the granular tubules became obvious on day 25. These results indicate that the development of trypsin-like esteroproteases faithfully reflects the differentiation of granular tubules in the mouse submandibular gland, except in the neonatal period.This work was supported in part by Grant-in-Aid for Scientific Research from the Ministry of Education, Science and Culture, Japan 相似文献
118.
Saya Tamura Takuma Hayashi Hideki Tokunaga Nobuo Yaegashi Kaoru Abiko Ikuo Konishi 《Current issues in molecular biology》2021,43(2):1188
Uterine leiomyoma, also known as fibroids, is the most common benign neoplasm of the female genital tract. Leiomyoma is the most common uterine tumor. The leiomyoma subtypes account for approximately 10% of leiomyomas. Intravenous leiomyomatosis, a uterine leiomyoma subtype, is an intravascular growth of benign smooth muscle cells, occasionally with pelvic or extrapelvic extension. Uterine leiomyosarcoma, a malignant tumor, tends to metastasize hematogenously, and distant metastasis to the lungs and liver is common. Therefore, the oncological properties of this intravenous leiomyomatosis resemble those of the malignant tumor uterine leiomyosarcoma. Cancer stem cells migrate to distant organs via intravascular infiltration, leading to micrometastases. We examined the oncological properties of intravenous leiomyomatosis using molecular pathological techniques on tissue excised from patients with uterine leiomyoma. CD44-positive mesenchymal tumor stem-like cells were detected in both patients with intravenous leiomyomatosis and uterine leiomyosarcoma. The oncological properties of intravenous leiomyomatosis were found to be similar to those of uterine leiomyosarcoma. However, in intravenous leiomyomatosis, cyclin E and Ki-67-positive cells were rare and no pathological findings suspecting malignancy were observed. It is expected that establishing a treatment method targeting cancer stem cells will lead to the treatment of malignant tumors with a low risk of recurrence and metastasis. 相似文献
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