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From 1976 to 1985, 277 cases of carcinoma of the esophagus were resected in the Second Department of Surgery, Tohoku University School of Medicine. Postoperative cardiocirculatory disturbances occurred in 114 cases (41.2%), arrhythmia being the disturbance most frequently observed (86.8%). Low cardiac output syndrome occurred in 8 cases and myocardial infarction occurred in 3 cases. The majority of the cases were treated successfully, but 5 patients died within one month after operation. Causes of death were as follows: myocardial infarction, constrictive pericarditis, cardiac tamponade, non-occlusive mesenteric ischemia and acute cardiac failure. Postoperative arrhythmia occurred mainly up to the third postoperative day. Low cardiac output syndrome occurred just after operation or on the first postoperative day. All cases of myocardial infarction occurred on the first postoperative day. The rate of occurrence of cardiocirculatory disturbances in aged patients (greater than or equal to 70) was significantly higher than other group (less than or equal to 69), (56.7%:38.1%, p less than 0.05). The rate of occurrence of cardiocirculatory disturbances in patients who had a history of hypertension or in patients with abnormal preoperative electrocardiographic findings were relatively higher than those in patients who had no history of hypertension or in patients with no abnormal preoperative electrocardiographic findings. The rate of occurrence of cardiocirculatory disturbances in patients who had undergone total resection of the thoracic esophagus was significantly higher than that in patients who had undergone partial resection of the thoracic esophagus (42.8%:23.8%, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The occurrence sites of intracranial primary germ cell tumors are most often the pineal and suprasellar regions. The histological type observed most frequently in these tumors is germinoma. Cases of embryonal carcinoma arising in the basal ganglia are rarely reported. To our knowledge, only 4 such cases have been previously reported in the literature. A case of an embryonal carcinoma arising in the basal ganglia is reported. A 17-year-old boy was admitted to our hospital on July 30, 1988 because of headache and vomiting, and a right hemiparesis. On admission, physical inspection showed no abnormalities and neurological examination revealed obtunded consciousness, a right central facial paresis and a right hemiparesis with Hoffman and Babinski reflexes. Noncontrast CT scan showed a large mass of low-to slightly high-density in the region of the left basal ganglia accompanied with midline shift and ventricular dilatation. Enhancement of the lesion was made by contrast CT scan. It was not homogeneous. Cerebral angiogram displayed a contralateral shift and an unrolling of the anterior cerebral artery, a lateral stretch of middle cerebral artery, a downward stretch of anterior choroidal artery and a tumor stain fed by the Heubner artery. On August 3, left frontotemporal craniotomy was performed. The tumor was totally removed in a piecemeal manner using microsurgical techniques. Histopathological diagnosis was mixed-type of germ cell tumor comprising embryonal carcinoma and teratoma. Postoperative CT scan showed complete disappearance of the tumor. A course of radiation of 4950 rads and two courses of a combination chemotherapy with cis-platinum, vinblastine and bleomycin were given within 3 months after the operation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Marijuana affects neural functions through the binding of its active component (Delta(9)-THC) to cannabinoid receptors in the CNS. Recent studies have elucidated that endogenous ligands for cannabinoid receptors, endocannabinoids, serve as retrograde messengers at central synapses. Endocannabinoids are produced on demand in activity-dependent manners and released from postsynaptic neurons. The released endocannabinoids travel backward across the synapse, activate presynaptic CB1 cannabinoid receptors, and modulate presynaptic functions. Retrograde endocannabinoid signaling is crucial for certain forms of short-term and long-term synaptic plasticity at excitatory or inhibitory synapses in many brain regions, and thereby contributes to various aspects of brain function including learning and memory. Molecular identities of the CB1 receptor and enzymes involved in production and degradation of endocannabinoids have been elucidated. Anatomical studies have demonstrated unique distributions of these molecules around synapses, which provide morphological bases for the roles of endocannabinoids as retrograde messengers. CB1-knockout mice exhibit various behavioral abnormalities and multiple defects in synaptic plasticity, supporting the notion that endocannabinoid signaling is involved in various aspects of neural function. In this review article, the authors describe molecular mechanisms of the endocannabinoid-mediated synaptic modulation and its possible physiological significance.  相似文献   
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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   
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Our basic techniques for the management of difficult cases of laparoscopic cholecystectomy (LC) are presented in this article. If access to Calot's triangle cannot be gained safely, dissection should be started at the fundus or body of the gallbladder (GB), rather than the neck (fundus-first method). In cases with a short and wide cystic duct, a transfixing suture should be applied for ligation instead of clipping. EndoGIA is useful for ligating and transecting this case to avoid a subsequent stricture caused by normal method of ligation. Intraoperative cholangiography should be performed near the neck of the GB in cases in which orientation is lost during dissection. More dissection should be performed in the direction of the junction of the bile ducts after orientation is regained. In cases with GB filled with stones accompanied by severe fibrosis, part of the GB is incised to remove the stones and expose the lumen of the GB. Confluence stones can be removed by placing an incision on the GB side of the junction of the duct. The incised part is closed with suture. A cystic tube (C-tube) is placed in the common bile duct through the cystic duct for decompression. In more difficult cases in which dissection cannot be started safely at any location, the body and the fundus of the GB are excised, and a drain is placed at the neck of the GB. Dissection can be carried out from the main surgeon's or the assistant's side depending on the situation, and cooperation between the two surgeons is mandatory to achieve safe LC in difficult cases. When performing the LC, one must have a low threshold for converting to open surgery if injuries cannot be managed safely.  相似文献   
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Expression of six proto-oncogenes (fos, myc, myb, Ki-ras, Ha-ras, and N- ras) in 43 cases of non-Hodgkin's lymphoma was analyzed by means of in situ hybridization. Biotinylated DNA probes of the six oncogenes and those of immunoglobulin H (IgH) gene and T-cell receptor beta (TCR beta) chain gene were used. The results of in situ hybridization performed under blind conditions by IgH gene and TCR beta chain gene probes were compatible with those of typing by cell surface markers. The nuclear protein-related proto-oncogenes, fos, myc, and myb, were expressed in about 70% to 80% of all cases regardless of phenotype, histology, or histologic grade. On the contrary, genes of ras family were expressed in more limited numbers of cases except for the Ki-ras gene, which was more frequently expressed by cases of the T-cell immunophenotype with a high malignancy grade. The results of dot hybridization with RNA extracted from some cases were compatible with those of in situ hybridization, further demonstrating the specificity of in situ hybridization.  相似文献   
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We report an 81-year-old patient with progressive dementia, disinhibition, and gait disturbance. He showed visuospacial disorientation, apathy, and gait disturbance at 76 years of age. When he was 77 years old, he was diagnosed Parkinson's disease and treated with the 1-dopa, the dopamine agonist, the amantadin, and the anti-cholinergic drug. These treatments didn't improve his motor disturbances. His motor disturbances, apathy, and abnormal behavior progressed gradually. He was admitted to the hospital at the age of 77. He was severely demented and akinetic. Sometime, violent behavior and hallucination were seen. The brain MRI showed frontotemporal lobe atrophy and severe leukoaraiosis of the frontal white matter. At 79 years of age, he became mute and bedridden. When he was 80 years old, large infarction occurred in his occipital lobe. He died due to renal failure and respiratory suppression at 81 years of age. His brain was examined pathologically. At the neurological CPC, the chief discussant arrived at the conclusion that his diagnosis was Binswanger's disease. Other possibilities discussed were FTD, CBD, and progressive subcortical gliosis. The post-mortem examination revealed diffuse white matter degeneration due to atherosclerotic change of the small artery, many lacunar infarctions, and severe infarction of the occipital lobe. These findings led the diagnosis of Binswanger's disease and cerebral infarction.  相似文献   
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