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1.
Congenital absence of the portal vein (CAPV) is a rare malformation of the splanchnic venous system. Although CAPV is usually detected in the pediatric age group, our patient was a 35-year-old woman. She had been diagnosed with CAPV in 1996 when she was 27 years old. In 1998, she was placed on hemodialysis due to chronic renal failure. After several episodes of encephalopathy in 2002, liver transplantation (LT) was recommended to her and her family. Since there was no suitable living donor candidate, she was put on the waiting list for a deceased donor liver transplant in Japan. In 2004, her ammonia level increased to around 300 microg/dl, and she went into a coma lasting for three days. After recovering from this event, she underwent a living domino transplantation using a whole liver donated by a familial amyloid polyneuropathy (FAP) patient. Her portal vein, which had drained directly into the inferior vena cava (IVC), was transected together with a cuff of the IVC wall and anastomosed to the graft liver portal vein in an end-to-end fashion. In conclusion, liver transplantation proved to be a safe and effective way to save this patient and improve her quality of life.  相似文献   
2.
Somatosensory vertex potentials (SVPs) were examined in 12 healthy subjects in response to painful electrical stimulation of the finger. SVPs consisted of N1, P1, and N2. The average latencies of the 3 peaks were 150, 225, and 350 msec, respectively. The latency and amplitude of each potential were reproducible for each subject. Recovery functions of the SVPs were analyzed in 10 subjects. A pair of stimuli were delivered to the right or left finger with interstimulus intervals (ISIs) of 50, 100, 150, 200, 350, 500 and 650 msec. SVPs partially recovered with the shortest ISI (50 msec). Full recovery could not be obtained even with the longest ISI (650 msec). Differences in recoveries within 650 msec of ISI were not observed between right and left stimulations. To examine the interaction between SVPs evoked by right and left finger stimulation, recovery functions from prior contralateral finger stimulation were analyzed with the same ISIs. SVP recoveries for right after left or left after right patterns of stimulus delivery were nearly the same as those for ipsilateral ones. It is suggested that SVPs are generated at nearly the same site in the sensory pathway regardless of the side stimulated.  相似文献   
3.
A case of recurrent medullary thyroid cancer (MTC) was evaluated with123I-MIBG,99mTc(V)-dimercaptosuccinic acid (DMSA), and201Tl scintigraphy. This patient had been operated on for MTC in the right thyroid. Recently a left neck mass was noticed, and was suspected of being a. recurrence of MTC based on increased plasma calcitonin (CT) and carcinoembryonic antigen (CEA). He was operated on for the neck mass which revealed MTC, and papillary thyroid cancer was incidentally found in the left thyroid, but the CT and CEA levels remained high, and remaining MTC tumor was suspected. But the location of the tumor was unknown. Although99mTc(V)-DMSA scintigraphy is generally believed to be superior in sensitivity to123I-MIBG scintigraphy, it did not demonstrate the tumor site but201Tl and123I-MIBG did. Furthermore,123I-MEBG scintigraphy has greater specificity for tumors which arise in the neural crest. Judging from the results of this case and cases reported in the literatures, both123I-MIBG and99mTc(V)-DMSA should be performed in the detection of recurrent MTC.  相似文献   
4.
Cardiovascular effects of (2'R)-4'-O-tetrahydropylanyladriamycin X HCl (THP) and doxorubicin (adriamycin, ADM) were studied in hamsters. In experiments to observe acute effects, THP was administered intravenously at a dose of 12.5, 25.0 or 50.0 mg/kg, and ADM at 1.56, 3.13 or 6.25 mg/kg was given to different subjects. The THP caused slight ECG alterations at a dose of 12.5 mg/kg. At a dose of 25.0 mg/kg or 50.0 mg/kg, THP caused moderate to remarkable alterations in ECG like a widening of PR and PRc interval, A-V block, ST segment depression and T wave flattening. The ADM caused moderate to remarkable alterations in ECG at a dose of 3.13 mg/kg or 6.25 mg/kg, including arrhythmia, bradycardia, A-V block, ST segment changes and T wave flattening. These changes caused by THP and ADM recovered within 5 approximately 10 minutes after injection. Alterations in the ultrastructure of the myocardium caused by THP at a dose of 50.0 mg/kg included some cells with slight changes like swelling of mitochondria, focal intracellular edema, and enlargement of myofibrils. The ADM, at a dose of 3.13 mg/kg, induced severer swelling of mitochondria than THP, dilatation of sarcoplasmic reticulum, intracellular edema, and disorganization of myofilaments. At a dose of 6.25 mg/kg of ADM, these changes became more pronounced. In experiments to observe subacute effects, hamsters were treated with THP or ADM by daily intraperitoneal injections for 15 consecutive days, and then allowed to be recovered for 15 days. Dose levels of THP or ADM were 0.125, 0.25, 0.5 and 1.0 mg/kg. General toxicity, ECG, hematological and blood biochemical analysis, and electron microscopic examination were studied. In the ECG study, THP-treated hamsters showed a reversible elevation of R wave amplitude at a daily dose of 0.5 mg/kg. Widening of PR and PRc interval, elevation of R and S wave amplitude, and reduction of T wave amplitude were observed at a daily dose of 1.0 mg/kg of THP. Hamsters treated with ADM showed increase of heart rate, reduction of T wave amplitude, and shortening of PR and PRc interval at a daily dose of 0.5 mg/kg. Severe changes were observed at a daily dose of 1.0 mg/kg of ADM including an increase of heart rate, elevation of R wave amplitude, reduction of S and T wave amplitude, and shortening of QT interval. The electron microscopic examination revealed that THP-treated hamsters showed separation of intercalated discs, formation of myelin structure, and dilatation of T-tubules at a daily dose of 1.0 mg/kg. Similar changes were caused by ADM at a daily dose of 0.25 to 1.0 mg/kg.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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6.
To investigate spatial resolution requirements for digitized portal images in radiation therapy, observer performance tests were performed. One hundred twenty portal images were digitized with sampling frequencies of 0.700, 0.350, and 0.175 mm for observation. Receiver operating characteristic analysis was used to determine the acceptable sampling frequency for clinical portal images. The detectability of setup errors was significantly better on the original images than on the digitized images with sampling frequencies of 0.700 mm (P = .005) and 0.350 (P = .046). Some clinical disadvantages might accrue with the use of a sampling frequency of 0.350 mm or larger.  相似文献   
7.
To clarify the physiological role of the mechanism that adrenergic nerve inhibits Ach release from intramural cholinergic nerve endings, the influence of Midaglizole, alpha 2-adrenergic receptor antagonist, to postprandial gastrointestinal motilities in conscious dogs was investigated. Postprandial motilities of gastric antrum, duodenum, ileum, and colon were significantly enhanced by Midaglizole (3.0-5.0 mg/kg body weight, i.v.). These excitatory responses were abolished by atropine (0.05-0.1 mg/kg body weight, i.v.). On the other hand, in most cases (29 cases out of 32), when Midaglizole was administered during quiesent phase of IMC, no change occurred in gastrointestinal motility. However, after subliminal dose of pentagastrin or cisapride, which stimulated Ach release from intramural cholinergic neuron without development of motility, was administered, Midaglizole induced phasic, postprandial motility-like contraction in gastrointestinal tract. Even in the fasted state, when Midaglizole was administered intragastrically, irregular contractions with high amplitude occurred in every regions from gastric antrum to colon. And these excitatory responses were abolished by atropine. Similar reaction was observed also in truncal vagotomized dogs. These results suggest that it is the physiological mechanism that adrenergic nerve presynaptically inhibits Ach release from intramural cholinergic neuron, which is the main mechanism of development of postprandial motility, acting on alpha 2-adrenergic receptor, and has tonic control of postprandial motility.  相似文献   
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9.
S-adenosylhomocysteine hydrolase is a prospective target for developing new anti-malarial drugs. Inhibition of the hydrolase results in an anti-cellular effect due to the suppression of adenosylmethionine-dependent transmethylations. Based on the crystal structure of Plasmodium falciparum S-adenosylhomocysteine hydrolase which we have determined recently, we performed mutational analyses on P. falciparum and human enzymes. Cys59 and Ala84 of the parasite enzyme, and the equivalent residues on the human enzyme, Thr60 and Gln85, were examined. Mutations of Cys59 and Thr60 caused dramatic impact on inhibition by 2-fluoronoraristeromycin without significant effect both on its kinetic parameters and on inhibition constant against noraristeromycin. In addition, the impact was independent from the electronegativity of the side chain of the substituting residue. These results showed that steric hindrance between a functional group at the 2-position of an adenine nucleoside inhibitor and Thr60 of the human enzyme, not an electrostatic effect, contributed to inhibitor selectivity.  相似文献   
10.
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