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61.
We reviewed 12 cases of infarcts in the territory of the anterior choroidal artery (AChA) on CT and/or MRI. In each case vascular occlusion in the region was verified angiographically. Although the extent of the lesion on CT/MR images was variable, all were located on the axial images within an arcuate zone between the striatium anterolaterally and the thalamus posteromedially. The distribution of the lesions on mutiplanar MRI conformed well to the territory of the AChA demonstrated microangiographically. The variability of the extent of the infarcts may be explained by variations in the degree of occlusive changes in the AChA or the development of collateral circulation through anastomoses between the AChA and the posterior communicating and posterior cerebral arteries. The extent of the lesion appeared to be closely related to the degree of neurological deficit.  相似文献   
62.
MRI of the brain in chronic carbon monoxide poisoning   总被引:3,自引:0,他引:3  
We examined 13 patients with chronic carbon monoxide (CO) poisoning by magnetic resonance imaging (MRI); all of them had been in an explosion in a coal mine 25 years previously. Symmetrical globus pallidus lesions were observed in 12, as was degeneration of the white matter, with focal cortical atrophy. The temporal parietal and occipital lobes were usually affected, the parietooccipital region being the most frequently and extensively damaged. Of the 12 patients with white matter degeneration 7 had definitely asymmetrical cortical and subcortical lesions. There were 6 patients with dilated temporal horns, probably due to atrophy of the hippocampal gyri. A history of CO inhalation and an awareness of the typical distributions of lesions are important for recognition of the effects of CO poisoning, especially when patients are in the chronic stage.  相似文献   
63.
To apply Nd:YAG laser irradiation through a new sapphire tip contact laser method to catheter ablation in treatment of tachy-arrhythmias, effects of laser irradiation on ventricular myocardium were investigated in 10 mongrel dogs. Nd:YAG lase (1064nm) discharges were delivered to different sites on the endomyocardium at power of 5, 10, 15, 20 or 25w with duration of 3, 5, or 10 seconds (sec.) respectively in closed beating hearts. Histopathologically, the lesion irradiated was clearly demarcated from the normal myocardium by the construction band necrosis zone. The depth of injured myocardium was less than 2mm with 3 sec. irradiations, with 5 sec. from 1 mm to 4 mm in proportion to power increase, with 10 sec. from 3mm to 8 mm in proportion to the power from 5w to 15w and could not be measured in cases of more than 20w irradiations. Although with every irradiation duration, the depth of injury increased in proportion to the power increase. With the same total energy, a longer time of irradiation produced deeper injury than a shorter time. This method makes it easier to keep the laser positioned to target than bare laser, and is suitable for use in catheter ablation.  相似文献   
64.
In an attempt to review the Japanese epidemiology of the anaphylactic and/or anaphylactoid reactions in the perioperative period, we investigated 105 cases with clinical features of anaphylactic and/or anaphylactoid reaction, which are reported in the Japanese anesthesiology-related journals from 1952 to 1990. Eighty-nine percent of the cases were reported during the last decade. There were 66 males and 34 females. The majority of the patients were below 60 years of age, and most of the patients were in their teens and fifties. Ninety percent of the patients had no past history of drug-induced allergy nor tendencies of atopy. Ninety-four percent of the patients recovered completely without any sequelae, and 0.95 percent of them recovered with serious complications. Deaths occurred in 4.67% of the patients. Most frequent clinical signs were cardiovascular (91.4%) and cutaneous (84.8%) manifestations. Respiratory, signs appeared in 41% of the patients. Patients are frequently unconscious and covered with drapes, and early signs and symptoms of anaphylaxis can be masked. In 25% of the patients cardiovascular collapse, including cardiac arrest and undetected blood pressure, appeared as the first noticeable sign. Causative drugs were confirmed immunologically in 5.7% of the patients. In other cases, causative drugs were presumed based on clinical course. Causative drugs and presumed causative drugs were varied, including blood and blood products (24 cases), intravenous anesthetics (19 cases), local anesthetics (15 cases), and muscle relaxants (9 cases), which were used generally in the perioperative period.  相似文献   
65.
66.
Non-hormonal adrenocortical adenoma with oncocytoma-like appearances   总被引:5,自引:0,他引:5  
We report a case of non-hormonal adrenocortical adenoma. The tumor was removed en block with the adrenal gland. The specimen was 5.0 X 4.5 X 3.0 cm, weighed 30 g and was solid. Histologically, this tumor had an oncocytoma-like appearance. However, as there is no concept of oncocytoma in connection with adrenocortical adenoma, this case was diagnosed as adrenocortical adenoma. A case with such histological findings has never been reported.  相似文献   
67.
Positron Emission Tomography (PET) allows in vivo visualization of the expression and function of protein using a radioligand. Quantitative analysis of serotonin transporter, receptors, and the function of P-Glycoprotein has been performed in living human brains. Furthermore, the relationship between the phenotype of those proteins and their genetic polymorphism has also been investigated. Regarding the effect of antipsychotics on dopamine D2 receptor, occupancy and its time-course have been measured in a living body using PET. This approach can provide in vivo pharmacological evidences of antipsychotics and establish a rational therapeutic strategy. PET is a powerful tool not only in the field of brain research but also drug discovery and individual medicine.  相似文献   
68.
Electrochemotherapy is a novel antitumor treatment involving the systemic administration of bleomycin followed by the delivery of electrical pulses to the tumor. The present study investigates the effects of electrochemotherapy on the growth of colon 26 cells inoculated subcutaneously into the backs of BALB/c mice. The mice were divided into the following four experimental groups: 20 that received no further treatment after the inoculation of colon 26 cells (control group); 20 that received 500 μg of bleomycin intraperitoneally 7 and 9 days after the inoculation (BLM group); 20 that received electric pulses to the tumor 7 and 9 days after the inoculation (EP group); and 30 that received electrochemotherapy 7 and 9 days after the inoculation (ECT group). During 28 days of observation, no deaths due to tumor progression occurred in the ECT group, but there were 18 in the control group, 11 in the BLM group, and 18 in the EP group. While weight loss was observed in all groups, it was most remarkable in the control group. Tumor growth was significantly inhibited in the ECT group, compared to the other experimental groups (P<0.01). The results of this study demonstrated that electrochemotherapy significantly inhibited the growth of colon 26 tumors in mice, without causing any remarkable adverse effects.  相似文献   
69.
1. Endothelin-3 (ET-3) elicited relaxations at low concentrations (up to 10(-8) M) and contractions at higher concentrations in dog isolated coronary arteries precontracted with prostaglandin F2 alpha (PGF2 alpha). The relaxation by ET-3 was not affected by endothelium denudation nor treatment with NG-nitro-L-arginine, but was abolished or reversed to a contraction by treatment with indomethacin and markedly suppressed by tranylcypromine, a PGI2 synthetase inhibitor, or diphloretin phosphate, a prostaglandin receptor antagonist. ET-1 produced only concentration-dependent contractions. 2. BQ-123, a new selective ETA receptor antagonist, caused relaxation of the strips contracted with ET-3 in a dose-dependent manner and prevented the ET-3-induced contraction but did not affect the contraction produced by PGF2 alpha. The relaxation caused by ET-3 was enhanced by treatment with BQ-123. 3. It is concluded that the relaxations elicited by ET-3 in dog coronary arteries are mediated via liberation of PGI2 by activation of non-ETA receptors, located in subendothelial tissues, possibly smooth muscle cells, whereas the peptide-induced contractions are mediated via ETA receptors.  相似文献   
70.
A 66-year-old man died of massive gastrointestinal hemorrhage caused by a fistula between the third portion of the duodenum and the abdominal aorta. An autopsy revealed that duodenal tuberculosis had resulted in the development of a fistula into the aorta with no pathological changes, and no active pulmonary tuberculosis was found. Duodenal tuberculosis and primary aortoduodenal fistula (ADF) without an aneurysm are both extremely rare. Thus, we report herein a unique case of primary aortoduodenal fistula without an abdominal aortic aneurysm, but associated with duodenal tuberculosis, and review the current literature.  相似文献   
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