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21.
Samples from seventy autopsy cases ranging from 27 to 79 years of age who had shown no evidence of renal or malignant diseases were examined histologically to clarify renal changes with age. We evaluated scores for renal histological change and referred the scores to clinical laboratory data; blood pressure, complete blood counts (RBC count, hematocrit, hemoglobin), serum chemistry values (creatinine, urea nitrogen, total cholesterol, total protein, sodium, potassium, chloride) and urinalysis (protein, sediment). We found the score to be related to serum creatinine level, blood urea nitrogen level and the degree of hematuria but not related to the other factors. The progression of arteriosclerosis, tubulo-interstitial change and global sclerosis were found to be severe with ageing. Also renal weight decreased with increasing age. However there were great differences among individuals in the extent of changes. We could not assume histological changes were generally severe in those of more than 55-65 years of age. It was impossible to clarify renal states only with clinical findings. Some kidneys had severe histological changes though less than 2.0 mg/dl of serum creatinine level. It suggests that living relatives and cadavers over 60 years old can be donors for renal transplantation when there are no significant findings of abnormality in preoperative evaluations of their physical state. If insufficient examinations are done, we cannot determine which of them will be good donors. Therefore preoperative biopsy is the best way to evaluate donor suitability. To evaluate only clinical data, it is necessary that serum creatinine level be less than 1.2 mg/dl, blood urea nitrogen level be less than 23 mg/dl and there be no hematuria. 相似文献
22.
Assessment of skull base involvement of nasopharyngeal carcinoma by bone SPECT using three detectors system] 总被引:2,自引:0,他引:2
N Yui T Togawa F Kinoshita F Shimada Y Akiyama 《Kaku igaku. The Japanese journal of nuclear medicine》1992,29(1):37-47
SPECT of the skull was performed on twelve patients with histologically proven nasopharyngeal carcinoma using newly developed three detectors SPECT system (Toshiba GCA 9300A) mounted with fan-beam collimators, for the purpose of early detection of skull base involvement of the disease. This SPECT system has extremely improved resolution with FWHM of 8 mm in the center, and it provides clear tomographic images of the skull which has anatomically complex structure. SPECT image was taken 3 hours after injection of 740 MBq (20 mCi) of 99mTc-MDP following whole body skeletal survey. In twelve patients with confirmed nasopharyngeal carcinoma, 8 patients showed positive findings on SPECT. Three of SPECT positive patients also showed destructive findings on CT. Other five positive patients did not show destructive findings on CT at their initial examinations, but in three of them CT findings turned to positive later. SPECT was superior to CT in early detection of skull base involvement. We believe that SPECT of the skull is a diagnostic tool for early detection of skull base involvement of nasopharyngeal carcinoma. 相似文献
23.
Summary Ghost tangles, neurofibrillary tangles (NFTs) emerging into extracellular space, appear to be subjected to some microglial association in addition to an invasion of astrocytic processes. Our findings lead us to speculate that the NFTs undergo structural and immunocytochemical modification. Electron microscopic observation of the NFTs in the vascular region indicated either the discharge of NFTs into the vessel or formation of NFTs in the astrocytic end-foot. 相似文献
24.
A 30-year-old female received a head injury at the age of 22 years. Subsequently neurological and psychiatric symptoms, such as personality change, urinary incontinence, dementia and gait disturbance developed. On admission, her cognitive function was severely impaired. Brain CT disclosed cerebral atrophy, dilatation of the lateral ventricle and calcification of the basal ganglia. Pathologically membranous structures were recognized in bone marrow. On the basis of these clinical findings, a diagnosis of Nasu-Hakola's disease was made. In this case, a T2-weighted MRI finding of reduced signal intensity in the thalamus and putamen was characteristic. This finding may be related to intracranial calcification. 相似文献
25.
Jira Chindasombatjaroen Naoya Kakimoto Hironori Akiyama Kazuko Kubo Shumei Murakami Souhei Furukawa Mitsunobu Kishino 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(6):e52-e57
The calcifying cystic odontogenic tumor is a rare benign odontogenic lesion. This report documents a case of this lesion associated with odontoma arising from the anterior maxilla in a 14-year-old boy. The diagnosis was confirmed based on computerized tomography findings, which clearly depicted the internal structures obscured in conventional images. 相似文献
26.
T Ohta T Nagakawa K Ueno K Maeda N Ueda M Kayahara T Akiyama M Kanno I Konishi R Izumi 《The Japanese journal of surgery》1990,20(1):36-43
Between 1978 and 1988, 15 patients with gallbladder cancer and 2 patients with bile duct cancer were seen among 49 patients with anomalous union of the pancreaticobiliary ductal system. Radiographic findings revealed two types of this anomalous condition: one in which the pancreatic duct entered the common bile duct (type 1) and one in which the common bile duct entered the pancreatic duct (type 2). In gallbladder cancer, the common bile duct presented no dilatation, or in some patients, mild dilatation, and type-1 anomalous union was frequently found among these patients. In contrast, the two patients with bile duct cancer had cystic dilatation of the common bile duct and type-2 anomalous union. The bile amylase level, which was determined in seven patients, was extremely high in all the patients. Histopathologically, the tumors in most patients showed papillary to papillo-tubular proliferation in the mucosal layer while atypical epithelial hyperplasia was noted in the vicinity of the tumor area. These findings suggest that this congenital anomaly in both ducts results in a loss of the normal sphincteric mechanism of the duodenal papilla, and that chronic relapsing cholecystitis or cholangitis, caused by the reflux of pancreatic juice into the biliary tract, can induced progressive changes to atypical epithelial hyperplasia which may develop into carcinoma. 相似文献
27.
Effects of repeated exposure to Fenitrothion (Sumithion) powder on erythrocyte membrane acetylcholinesterase (AChE) and plasma cholinesterase (PChE) were studied. Rats (Wistar, male) were exposed to fenitrothion powder for 2 hrs/day, 5 days/week for up to 3 months. The suppression of AChE and PChE increased as the exposure period and exposure concentration increased, although no suppression of AChE was found after a single 4-hr exposure. The persistence of AChE inhibition after the termination of exposure increased with the increase of the exposure period and was longer than that of PChE. Therefore, the AChE activity seems to be useful in examining the response to the repeated exposure to fenitrothion powder. 相似文献
28.
Mucoadhesive Microspheres Containing Amoxicillin for Clearance of Helicobacter pylori 总被引:5,自引:0,他引:5
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Naoki Nagahara Yohko Akiyama Masafumi Nakao Mayumi Tada Megumi Kitano Yasuyuki Ogawa 《Antimicrobial agents and chemotherapy》1998,42(10):2492-2494
In an effort to augment the anti-Helicobacter pylori effect of amoxicillin, mucoadhesive microspheres, which have the ability to reside in the gastrointestinal tract for an extended period, were prepared. The microspheres contained the antimicrobial agent and an adhesive polymer (carboxyvinyl polymer) powder dispersed in waxy hydrogenated castor oil. The percentage of amoxicillin remaining in the stomach both 2 and 4 h after oral administration of the mucoadhesive microspheres to Mongolian gerbils under fed conditions was about three times higher than that after administration in the form of a 0.5% methylcellulose suspension. The in vivo clearance of H. pylori following oral administration of the mucoadhesive microspheres and the 0.5% methylcellulose suspension to infected Mongolian gerbils was examined under fed conditions. The mucoadhesive microspheres and the 0.5% methylcellulose suspension both showed anti-H. pylori effects in this experimental model of infection, but the required dose of amoxicillin was effectively reduced by a factor of 10 when the mucoadhesive microspheres were used. In conclusion, the mucoadhesive microspheres more effectively cleared H. pylori from the gastrointestinal tract than the 0.5% methylcellulose suspension due to the prolonged gastrointestinal residence time resulting from mucoadhesion. A dosage form consisting of mucoadhesive microspheres containing an appropriate antimicrobial agent should be useful for the eradication of H. pylori. 相似文献
29.
30.
Ei-ichi Akiyama Yuriko Takamura Yu Nagase 《Macromolecular chemistry and physics.》1992,193(6):1509-1519
Polyimide/polydimethylsiloxane (PI/PDMS) graft copolymer was prepared following the macromonomer method. First, 3-(3,5-diaminobenzyloxy)propyl-terminated polydimethylsiloxane (DAB-PDMS) was prepared by hydrosilylation of allyl 3,5-dinitrobenzyl ether with hydrosilyl-terminated PDMS, followed by catalytic reduction of the two nitro groups. PI/PDMS graft copolymer was synthesized by polycondensation of DAB-PDMS with 4,4′-oxydianiline (ODA) and 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA), followed by chemical imidation. The average degree of polymerization of the PDMS chain was in the range between 7 and 25. The resulting graft copolymers were soluble in several organic solvents. Membranes were prepared by solvent casting, followed by heating at 220°C in vacuo, upon which the membranes became hardly soluble in organic solvents. The gas permeability coefficients of the graft copolymer membranes were much greater than those of the polyimide homopolymer and of the same order as that of a PDMS membrane. Furthermore, a selective permeation of organic liquids, e.g., tetrahydrofuran, acetone and acetonitrile, was observed in the pervaporation of aqueous organic liquids through the copolymer membrane. 相似文献