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91.
The response of periodontal nerves to experimentally induced occlusal trauma in rat molars was assessed by immunohistochemistry for protein gene product 9.5 (PGP 9.5) at light and electron microscopic levels, and by computerized image analysis. The occlusal surface on the left upper first molar of 8-wk-old male Wistar rats was raised approximately 1 min under ether anaesthesia. The rats were perfusion-fixed on d 1, 2, 3, 4, and 7 after bite-raising and then decalcified for 2–3 wk. Frozen sagittal cryostat sections were stained by the avidin-biotin complex method. By the second day after bite-raising many Ruffini endings were swollen and their outline unclear at the light microscopic level. Transmission electron microscopy disclosed PGP 9.5 reaction products within Ruffini endings that had unusually long cytoplasmic projections extending through enlarged slits of the Schwann sheaths and also diffuse extracellular PGP 9.5-immunoreactivity near the Ruffini endings. From d 2 to 4, thin nerve fibres on the pressure side of the periodontal ligament were orientated irregularly and had a prominent beaded appearance. An increase in beaded nerve terminals occurred at d 2–4 post elevation, and decreased later. These results suggest that occlusal trauma induces specific changes in the distribution and shape of nerve terminals in the periodontal ligament. 相似文献
92.
Toshihisa Inoue MD Shigeru Watanabe MD Yoshiaki Masuda MD Katsuya Yoshida MD Hitoshi Imai MD Yasuo Imazeki MD Yoshiaki Ishizuya MD Masashi Koga MD Hirotoshi Kato MD Hiroo Ikehira MD Yukio Tateno MD 《Clinical imaging》1996,20(4):262-268
The magnetic resonance phase-contrast technique for the measurement of flow velocity and volume in true and false lumens was studied in six patients with chronic dissecting aneurysms. Phase-contrast images were obtained at a level perpendicular to the dissecting aneurysms of the descending aorta. As the maximum diameter of aneurysms increased, the ratio of the cross-sectional area of the false to the true lumen increased and the peak average velocity in the true lumen during systole was decreased. This technique proved invaluable for determining prognosis and operability for this condition. 相似文献
93.
Immunoreactive opsin and glial fibrillary acidic protein in persistent hyperplastic primary vitreous
An 8-month-old boy had an anterior type of persistent hyperplastic primary vitreous in the right eye. Results of needle biopsy, performed because of elevated intraocular pressure, disclosed clusters of blastic cells. The eye was enucleated on the suspicion of retinoblastoma. Histological examination showed retrolental fibrovascular tissue and retinal dysplasia. Immunoreactive opsin was detected in the innermost structures and in photoreceptor-like cells of rosettes. We conclude that photoreceptor cells differentiated to express opsin, even when neighbouring cells were abnormally arranged. An immunocytochemical study of glial fibrillary acidic protein demonstrated glial proliferation in the inner layer of the retina but not in the preretinal space. 相似文献
94.
S Kubo A Yasuoka T Rikitake T Shimoda K Fujita M Nakatomi K Hara 《Nihon Kyōbu Shikkan Gakkai zasshi》1991,29(9):1161-1167
The authors examined pulmonary hemodynamics with respect to underlying diseases, severity and type of chronic respiratory failure, and the incidence and effect of home oxygen therapy (HOT) in 155 patients with chronic lung diseases (old pulmonary tuberculosis (OTB) 45, chronic pulmonary emphysema (CPE) 54, chronic bronchitis (CBR) 42 and fibrosing lung disease (FLD) 14). They underwent right heart catheterization during a stable period, while breathing room air. The arterial PO2 ranged from 64.3 +/- 9.7 Torr (CBR) to 69.9 +/- 10.0 Torr (CPE), and the mean pulmonary arterial pressure ranged from 17.3 +/- 4.6 mmHg (CPE) to 20.6 +/- 5.4 mmHg (OTB). The incidence of pulmonary hypertension (PH, PA mean greater than or equal to 20 mmHg) was 53.3% in OTB, 40% in CBR, 35.7% in FLD, 23.8% in CPE, 69% in respiratory failure, 40% in quasi-respiratory failure, and 2.1% in non-respiratory failure. The percentage of patients who received HOT was 84.5% in respiratory failure and 54.1% in quasi-respiratory failure. Comparing Type I with Type II chronic respiratory failure, the incidence of PH was lower in the former than the latter (38.3% vs 80.6%), whereas HOT was applied to an equal percentage of patients (67.4%) in both groups. The effect of HOT was evaluated in 11 patients with chronic respiratory failure. The mean pulmonary arterial pressure was 22.7 +/- 4.7 mmHg before HOT, and decreased to 20.7 +/- 5.6 mmHg after 24.5 +/- 10.1 months of HOT. Although this difference was not significant statistically, this result suggests the desirable effect of HOT on pulmonary hemodynamics. 相似文献
95.
Yoshimi Otani Ichiro Yoshida Satoshi Ohki Motoi Kano Osamu Kawashima Masao Suzuki Yasushi Sato Toru Takahashi Akio Ohtaki Susumu Ishikawa Yasuo Morishita 《Surgery today》1997,27(9):812-815
Pulmonary aspergillosis associated with old tuberculosis is generally resistant to treatment. Thus, if patients are treated
only with conservative therapy, their condition continues to deteriorate due to repetitive hemoptysis, and may even become
critical. Surgical treatment is required for these patients; however, it is extremely difficult to resect the lesion due to
severe adhesions to the chest wall and vascular proliferation surrounding the lesion. We performed preoperative arterial embolization,
achieving good results in three patients with hemoptysis caused by pulmonary aspergillosis. The feeding arteries were embolized
using microcoils and/or gelatin sponges, and a lobectomy was safely carried out in all patients. We concluded that preoperative
arterial embolization is a safe and effective technique to prevent massive hemorrhage occurring at the time of surgery.
This work was presented at the 11th Annual Meeting of the Japanese Association for Chest Surgery, held in Kyoto, Japan, May
13–14, 1994 相似文献
96.
Tomoyuki Kawada M.D. Yasuo Kiryu M.D. Shigenobu Aoki Ph.D. Shosuke Suzuki M.D. 《Psychiatry and clinical neurosciences》1992,46(4):937-940
Abstract: The possibility on placing electrodes at Fpz-A2 instead of C3 -A2 was investigated to obtain a more stable configuration avoiding obstruction by the hair. Our original system of alpha wave detection by a microcomputer was used, and a total of 22 all-night hypnograms of five healthy young students waa recorded. Pearson's moment correlation coefficients of alpha wave % between the two positions were 0.780–0.948. Except for one subject, alpha wave % taken at Fpz-A2 tended to be 3–5% lower than that at C3 -A2 . The above analysis indicates that using EEG electrode position of Fpz-A2 is valid and useful as a stable electrode configuration for a long-time monitoring. 相似文献
97.
Gen Matsuo Yasuo Matsumura Kiyoshi Tadano Takashi Hashimoto Shiro Morimoto 《Clinical and experimental pharmacology & physiology》1997,24(7):487-491
1. The effects of sarafotoxin S6c (S6c), a selective endothelin ETB receptor agonist, on renal haemodynamics and urine formation were examined in anaesthetized dogs. 2. Intrarenal arterial infusion of S6c at a rate of 1 or 5 ng/kg per min produced a transient increase in renal blood flow (RBF), with no change in systemic blood pressure and heart rate; RBF then decreased gradually to below the basal value. There were significant and dose-dependent increases in urine flow and free water clearance and decreases in urine osmolality during S6c infusion, whereas urinary excretion of sodium and glomerular filtration rate (GFR) remained unchanged. Simultaneously, S6c administration elicited a marked increase in urinary excretion of nitric oxide (NO) metabolites, N02? and N03? (UNO*V). 3. In dogs simultaneously administered S6c (5 ng/kg per min) and iVG-nitro-L-arginine (NOARG; 40 (jig/kg per min), a NO synthase inhibitor, the renal vasodilator effect of S6c was abolished and marked reductions in RBF and GFR were observed. The S6c-induced diuretic action was not affected by NOARG. In the presence of NOARG, there was a small amount of UNOxV at the basal level and the administration of S6c did not increase UNOxV. 4. These results suggest that an intrarenal arterial infusion of S6c enhances the production of NO in the kidney and that this enhancement contributes to the peptide-induced renal vasodilation. In contrast, it is unlikely that S6c-induced water diuresis is related to NO production stimulated by this peptide. 相似文献
98.
Yasuo Aoki Souji Maruo Akira Arakawa Sadao Sasaki Seiki Hori 《Journal of orthopaedic science》1997,2(6):434-441
Changes in the nerve fibers of the spinal cord were studied in rat experimental epidural tumor models. Light microscopy showed
demyelinization in all with rats paraparesis and paraplegia. Cross-sectional views of nerve fibers stained with 3,3dipentyloxacarbo-cyanine
iodide, obtained by confocal laser scanning microscopy, showed distorted, shrunken fibers with a low fluorescence intensity.
Changes in the electrolyte contents of nerve fibers were studied by electron probe X-ray microanalysis. The K concentration
in axons and the myelin sheath was increased in the paraparesis group, but was decreased in the paraplegia group. These findings
suggest that, in the paraparesis group, compression of the spinal cord damaged cell membrane channels, which subsequently
caused an increase in intracellular K, a decline in the action potential, and low-intensity fluorescence of nerve fibers.
On the other hand, in the paraplegia group, destruction of cell membranes caused a decrease in intracellular K until it approached
the extracellular level. This reduced both the action potential and the fluorescence intensity. As Ca and Mg concentrations
in both axons and the myelin sheath increased in relation to the severity of neurologic damage, it appears that these electrolytes
may also play an important role in damage to nerve fibers. 相似文献
99.
We developed a microtrephine that can be used to create 0.9-mm or 0.5-mm, round, tear-free, anterior lens capsular openings. The 0.9-mm tip can be used to greatly facilitate experimental endocapsular cataract surgery followed by lens refilling. The 0.5-mm tip is useful for obtaining new anterior capsular openings. 相似文献
100.