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1.
The venous outlet of the corpus cavernosum is generally believed to be obstructed during erection. Some researchers, however, have demonstrated an increased venous outflow during erection. To elucidate this discrepancy, we carried out a pressure-flow study using a perfusion model of the penile deep artery in dogs. Various states of the corpus cavernosum, which were different in cavernous pressure, were induced by a delicate control of electrostimulation to the cavernous nerve. Inflow rate into the corpus cavernosum, inflow resistance and outflow resistance were simultaneously evaluated. The inflow rate in mild erection was higher than in the flaccid state, and the outflow rate was estimated to be also higher than in the flaccid state. A probable reason for the increased outflow rate was that the arterial resistance decreased remarkably, while the venous resistance only slightly increased. In full erection, both the inflow and outflow rates were lower than in the flaccid state because of a great venous resistance. Histological observation of the canine penis indicated that compression of draining veins passing through the tunica albuginea was weak in mild erection, while intense in full erection. It was proposed that in mild erection, the effect of venous occlusion was slight though that of arterial dilation was noticeable, resulting in an increase in the venous outflow. 相似文献
2.
Kenji Yoshimi Masatoshi Takeda Tsuyoshi Nishimura Takashi Kudo Yu Nakamura Kunitoshi Tada Nobuyoshi Iwata 《Brain research》1991,560(1-2):149-158
Changes in MAP2 and clathrin immunoreactivity were studied in gerbil hippocampus after transient cerebral ischemia. MAP2 immuno-reactivity decreased significantly by 1 h in the subiculum-CA1 and CA2 areas which correspond to reactive change, while no decrease was observed in CA1 until day 4. Before the initiation of delayed neuronal death, MAP2 immunoreactivity was not changed in CA1. On the other hand clathrin immunoreactivity increased in the pyramidal cell layer of CA1 by 3 h after ischemia and remained high for 2 days. Clathrin immunoreactivity in the pyramidal cell layer of CA1 diminished after delayed neuronal death. The transient change of clathrin was noted especially in CA1 in the period prior to delayed neuronal death. These results imply an abnormal change in clathrin turnover after ischemia, which may participate in the pathogenesis of delayed neuronal death. 相似文献
3.
H Hanyu H Arai H Katsunuma R Fujita C Tomori 《Nihon Ronen Igakkai zasshi. Japanese journal of geriatrics》1991,28(2):160-165
A neuroradiological study of crossed cerebellar atrophy (CCA) was performed using X-ray CT in 103 patients suffering from unilateral supratentorial cerebrovascular diseases. CCA was demonstrated in 9 (8.7%) of 103 patients. No difference between the occurrence of CCA in cerebral hemorrhage and that in cerebral infarction was found. CCA was seen in the chronic stage of cerebrovascular disease more than 3 years since stroke occurrence, and was found to be present more frequently and to a greater extent 7 years later. No correlation between the site of bleeding and the occurrence of CCA was found. Trans-synaptic degeneration of the corticopontocerebellar tract was considered in CCA following putaminal and combined hemorrhage involving an internal capsule lesion. However, in thalamic hemorrhage, retrograde degeneration within the cerebellorubrothalamic tract was presumed. CCA following cerebral infarction was seen in patients with massive lesions in the territory of the middle cerebral artery. Multivariate analysis showed that lesions of the parietal and frontal lobes appeared to greatly contribute to the development of CCA. As the degeneration and atrophy in the thalamus on the side of the lesion appeared early and frequently, it was suggested that retrograde degeneration of the cerebellorubrothalamic tract participated, in addition to anterograde corticopontocerebellar tract degeneration, in CCA following middle cerebral artery infarction. It is likely that CCA is caused by both transsynaptic degeneration of the corticopontocerebellar tract and the cerebellorubrothalamic tract. 相似文献
4.
Symptomatic narcolepsy, once regarded as common, is now believed to be very rare. A 32-year-old man had a history of recurrent sleep attacks. A magnetic resonance imaging scan revealed a third ventricle tumor. The tumor was totally removed, and the histology was a craniopharyngioma. The symptoms ceased after the operation. The chronological correlation and the anatomical location of the tumor suggest that the patient had a symptomatic narcolepsy caused by the tumor. This is the first report that documents the cessation of narcolepsy attacks after tumor removal. 相似文献
5.
We report a 47-year-old alcoholic man with alcoholic pellagra encephalopathy (APE) showing myoclonus and ataxia as chief complaints. He had been a heavy drinker for 30 years. He had noticed appetite loss and subsequently showed a subacutely progressive gait disturbance. He had no history of diarrhea, dementia, or dermatitis. On admission, he showed severe alcoholic liver cirrhosis with a large amount of ascites, limbs and truncal ataxia, myoclonus of the limbs and areflexia, although his consciousness was alert and there were no sign of dermatitis. Though the plasma level of ammonia was normal, we started administration of amino acids suspecting hepatic encephalopathy. Symptoms showed no improvement, and subsequent administration of thiamine was also ineffective. A decreased serum level of niacin was demonstrated. After administration of nicotinamide, the symptoms improved gradually. This patient received a diagnosis of APE. Endemic pellagra, characterized by the classical triad of dermatitis, diarrhea and dementia, is known to be caused by a dietary deficiency of the niacin, and has now become very rare in developed countries. At present, pellagra is encountered most often in patients with chronic alcoholism, which is called APE. APE patients often show only disturbance of consciousness. Although several reports has described ataxia and myoclonus in patients with APE, APE patients with myoclonus and ataxia as chief complaints have not previously been reported. On autopsy cases, central chromatolysis of neurons in the dentate nucleus of the cerebellum, gracile and cuneate nuclei, and the Clarke's column has been demonstrated. The APE patients would show myoclonus and ataxia as their first symptoms. In conclusion, we would like to emphasize that administration of niacin should be started for the treatment of chronic alcoholic patients showing myoclonus and ataxia even without the classical triads found in endemic pellagra patients. 相似文献
6.
Akihiko Suto Akira Tsuyuki Nobuyoshi Hiraoka Yasuhiro Hosoda Kiyoshi Kikuchi Yasuo Fujishir 《Surgery today》1994,24(10):915-917
A case of cystadenocarcinoma of the appendix with a large cystic lesion is reported. A 49-year-old man undergoing a routine ultrasonic scan was incidentally found to have an abdominal mass measuring some 30 cm in size. The clinical presentation was asymptomatic, and the patient underwent a laparotomy without ascertaining a diagnosis preoperatively. The lesion, which derived from the appendix, was removed and was found to be cystic and contained huge amounts of mucin. The histological findings revealed a well-differentiated cystadenocarcinoma of the appendix, and immunohistochemical staining of the epithelium and mucinous implants in the mass demonstrated a positive reaction for carcinogenic antigens, including carcinoembryonic antigen and carbohydrate antigen. 相似文献
7.
Relevance of inflammatory cell infiltrates for complete atrioventricular block in experimental murine myocarditis. 总被引:2,自引:0,他引:2
BACKGROUND: There are few systemic pathologic studies on myocarditis. This study aimed to clarify the pathologic characteristics of murine myocarditis. METHODS: We recorded serial electrocardiograms in experimental viral myocarditis in mice and then examined their cardiac pathology. After taking baseline electrocardiograms, we inoculated the mice intraperitoneally with the encephalomyocarditis virus. Electrocardiograms were serially recorded until 220 days after the virus inoculation. RESULTS: Serial electrocardiograms revealed ectopic beats, low voltage of the QRS complex, and the appearance of complete atrioventricular (AV) block. Corresponding myocardial lesions were found in the hearts of mice with these ectopic beats. Mononuclear cell infiltrations into the His bundle were most frequently found in mice with complete AV block. CONCLUSIONS: Inflammatory change with cellular infiltrations was the most common pathologic finding in mice with complete AV block. In clinical settings, anti-inflammatory therapy might be recommended for patients with myocarditis complicated with conduction disturbances. 相似文献
8.
Nobuyoshi Kawaharada Kiyofumi Morishita Johji Fukada Yoshikazu Hachiro Yasuaki Fujisawa Tatsuya Saito Yoshihiko Kurimoto Tomio Abe 《European journal of cardio-thoracic surgery》2005,27(4):622-625
OBJECTIVE: The risk of stroke caused by dislodgment of loose atheromatous plaque or mural emboli is increased by cross-clamping of the aorta. Some patients undergo descending thoracic aortic aneurysm repair with proximal aortic cross-clamping between the left common carotid artery and the left subclavian artery. The objective of this study was to determine the influence of proximal aortic cross-clamping in arteriosclerotic aneurysm or dissecting aneurysm repair. METHODS: Between May 1984 and May 2003, 81 patients underwent elective surgery for distal arch or descending aortic aneurysm repair with proximal aortic cross-clamping between the left common carotid artery and the left subclavian artery. To evaluate the influence of the proximal aortic cross-clamping, patients were divided into two groups: patients who had undergone arteriosclerotic aneurysm repair (group I, n=25) and patients who had undergone dissecting aneurysm repair (group II, n=56). RESULTS: Eight (9.9%) of the 81 patients had a stroke. Six strokes occurred in operations for arteriosclerotic aneurysm repair group I and two strokes occurred in operations for dissecting aneurysm repair group II (24 vs 3.6%; p=0.009). In-hospital mortality rates were 12% in group I and 8.9% in group II (p=0.70). Major postoperative complications included renal failure requiring hemodialysis (in 4.2% of the patients in group I and in 8.3% of the patients in group II, p=0.99) and pulmonary complication (in 20% of the patients in group I and in 16% of the patients in group II, p=0.67). CONCLUSION: Cross-clamping between head vessels should be avoided if at all possible when operating on patients who have arteriosclerotic descending thoracic aneurysms. 相似文献
9.
H Fukui H Ide F Hanyu H Ikemoto N Okushima Y Murata Y Sato A Yamada 《Gan to kagaku ryoho. Cancer & chemotherapy》1987,14(4):1106-1110
Subrenal Capsule Assay (SRCA) as a chemosensitivity test was performed on 14 esophageal squamous cell carcinomas in order to select a more effective form of chemotherapy. Of the 14 assays, 12 were evaluable. Mice were treated with anticancer agents (e.g. Cisplatin, Bleomycin, Methotrexate, Vindesine) on days 1 and 3 after transplantation, and on day 6, the sensitivities were determined. Fresh esophageal cancers yielded an evaluable assay rate of 74%. The implant grew progressively for six days in the remaining group of control mice. Histologically, host cell infiltration at the border of the implant was observed from day 3 after transplantation, and cells had degenerated or had been partially replaced by scar tissue by day 6. The results of chemosensitivity tests differed according to the anticancer agent used or from case to case. Clinically, correspondence between the assay results and clinical results was obtained in 5 out of 7 cases. SRCA is a new promising chemosensitivity test which is clinically useful, and the present results indicated the feasibility of its use in developing an effective chemotherapy for esophageal cancer. 相似文献
10.
Shiro Saito Makoto Hata Ryuichi Fukuyama Kosuke Sakai Jun Kudoh Hiroshi Tazaki Nobuyoshi Shimizu 《International journal of urology》1997,4(2):178-185
Background Mutation converts the H-ras gene into an activated oncogene in about 10% of human bladder cancers. Codons 12 and 61 are the major "hot spots" for activation. A simple and accurate method to detect point mutations in these codons may be clinically useful for early diagnosis of bladder cancer.
Methods Bladder cancer samples from 50 patients, plus 10 samples of normal bladder mucosa, were analyzed for possible point mutation of the H-ras gene at either codon 12 or codon 61. The H-ras gene DNA segments that include these 2 codons were amplified by PCR methods, then the possible presence of a point mutation was evaluated at each codon by susceptibility of the respective DNA segments to digestion with the restriction enzyme and by dot blot hybridization assay. A bladder cancer patient who had an H-ras gene mutation was examined to see whether the mutation was also detectable in the cells released in the urine.
Results Definite or possible point mutations were found in 6 (1 2%) out of 50 bladder cancer patients, while no mutation was detected in normal mucosa. A point mutation could also be detected in cells isolated from the patient's urine sample.
Conclusion The prevalence of point mutations at codon 1 2 or codon 61 of the H-ras gene found in this study was similar to that previously estimated for human bladder cancer by DNA transfection assay. The method we have used for detecting point mutations of the H-ras gene provides a simple and highly accurate way to detect mutated cancer cells even in the urine. It may be clinically usable for early diagnosis of bladder cancer. 相似文献
Methods Bladder cancer samples from 50 patients, plus 10 samples of normal bladder mucosa, were analyzed for possible point mutation of the H-ras gene at either codon 12 or codon 61. The H-ras gene DNA segments that include these 2 codons were amplified by PCR methods, then the possible presence of a point mutation was evaluated at each codon by susceptibility of the respective DNA segments to digestion with the restriction enzyme and by dot blot hybridization assay. A bladder cancer patient who had an H-ras gene mutation was examined to see whether the mutation was also detectable in the cells released in the urine.
Results Definite or possible point mutations were found in 6 (1 2%) out of 50 bladder cancer patients, while no mutation was detected in normal mucosa. A point mutation could also be detected in cells isolated from the patient's urine sample.
Conclusion The prevalence of point mutations at codon 1 2 or codon 61 of the H-ras gene found in this study was similar to that previously estimated for human bladder cancer by DNA transfection assay. The method we have used for detecting point mutations of the H-ras gene provides a simple and highly accurate way to detect mutated cancer cells even in the urine. It may be clinically usable for early diagnosis of bladder cancer. 相似文献