Age related changes of the thyroid gland of CF1 mice ranging in age from 15 days to 24 months were studied morphologically and biochemically. The mean diameter of follicles becomes larger with advancing age due to fusion of adjacent follicles, and there is also an increasing variability of follicle diameter. The volumetric density of lysosomes in the cytoplasm of epithelial cells lining follicles increases with age. In the younger (seven days to 1.5-month-old) mice, most lysosomes are small and homogeneously dense; these are considered to be the primary lysosomes necessary for the hydrolysis of reabsorbed colloid droplets. The heterogeneously dense, large lysosomes containing lipid-like droplets increase in number with age, especially in mice over 15 months. The specific activities of acid phosphatase, beta-glucuronidase and beta-galactosidase show a relative decrease with age after six months; although there may be an absolute increase. Some of the lysosomes observed in old animals may be residual bodies.
This paper describes the development of a reinforcing method for reinforced concrete (hereinafter RC) structures by using carbon fibers (hereinafter CF). This developed method attaches a light-weight CFUD prepreg material for reinforcement by laterally winding CF strand impregnated with epoxy resin, which is hardened under normal temperature. This method is economical because no skills and special tools are required. An RC pillar with circular cross section and a hollow RC test body assuming a chimney were used as models. The paper details the experiment. This method has been used in several ten existing RC stacks with effective reinforcing result. Resistance strengths of CF strands and UD prepregs were verified in an accelerated exposure test performed according to JIS A 1415, standard for plastic building materials. The effects of the anti-seismic reinforcement have resulted in improvement in shear resistance force in RC pillars by means of CF winding method, improvement in bending stress in RC structures as a result of CF attaching method, and effectiveness in repair of existing RC stacks. Sufficient exposure resistance has also been proved. A bending test by means of two-point concentrated loading has been performed as a weighted test. 4 figs.
The residual pancreatic exocrine function before and after pancreaticoduodenectomy (PD) for periampullary carcinoma was studied clinically as well as experimentally. In clinical instances (n = 35), the N-Benzoyl-L-Tyrosil-p-Aminobenzoic Acid test (BTPABA test) before and within two months after PD revealed reduction of the function compared with those in the control study. However, the test result one year after PD was improved compared with those before and within two months after operation, without differences from that of the control group. In new canine PD models in which drainage of the pancreatic duct, 50 per cent pancreatectomy and duodenojejunectomy were performed after three months of pancreatic duct obstruction, fibrosis surrounding the pancreatic duct was disclosed. However, the results of examination five months after PD revealed a milder degree of pancreatic fibrosis without aggravation of the lesion. The aforementioned findings indicated that the exocrine pancreas before PD was impaired due to obstructive pancreatitis and that the postoperative pancreatic function was well preserved at the level close to that in the control group even after approximately 50 per cent resection of the pancreas, if pancreatic duct drainage was effectively performed.
There are two different methods for coronary artery bypass grafting: end-to-side and side-to-side anastomosis. In vitro mock test, flow visualization and animal experiments were performed in parallel to compare the hemodynamic effect between two methods. Thus, bioengineers can provide practical useful information to the clinical team.
