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71.
Methotrexate (MTX) is a key drug in the chemotherapy for childhood acute lymphocytic leukemia (ALL). It is essential in the treatment of such areas as the central nervous system (CNS) and reproductive organs. High-dose chemotherapy is applied for this purpose to obtain an effective plasma concentration in the target organs.There are three major mechanisms of nephrotoxicity related with MTX. One is that induced by allergic reaction, which usually appears as interstitial nephritis. In this case MTX is contraindicated. Another is direct pharmacological toxicity against renal tubules. The third is precipitation of MTX, which plugs the renal tubules. The latter two are consequently dose dependent, and are usually associated with high-dose chemotherapy. To prevent these nephrotoxicities, hydration and alkalinization of the urine are performed to accelerate the urinary excretion and avoid the precipitation of MTX.  相似文献   
72.
Ultraviolet light (UV)-exposed rabbit skin was stained with a fluorescent thiol reagent or haematoxylin and eosin to investigate a time relationship between histochemical stainings for sulphhydryl (-SH) and disulphide (S-S) groups and sunburn cell (SBC) production. SBCs appeared by 8 h after irradiation, increased and showed a peak at 48 h, then declined to zero by 96 h. SBCs showing -SH staining increased to a maximum of 41--59% at 24--48 h and declined to 26--45% by 72 h, whereas S-S-stained SBCs were only a few at 8--24 h and then increased up to 65--85% by 72 h. The results seem to indicate that S-S linkage may occur in the process of SBC production.  相似文献   
73.
A case of pseudomyxoma peritonei that was first recognized bydyspnea and abnormal shadows on chest X-ray film is reported.The patient is a 67-yr-old woman who was found to have an abnormalshadow on chest X-ray filni on routine physical examinationwhen she was 47 yr old (1960). She had been asymptoniatic untilabout 2 yr before admission when she began to experience dyspneawith increased severity. On admission, the chest X-ray filmand com puted tomography showed bilateral pleural thickening.Drainage and decortica tion was carried out, and multiple cystsfilled with a gelatinous substance were found bilaterally inthe thoracic cavity. On the 66th hospital day, pan- peritonitisfollowing perforation of the appendix occurred and an emergencyoperation was performed. The patient died of acute renal failureon the 13th postoperative day. Pseudomyxoma peritonei originatingfrom pseudomucinous cystadenocarcinoma of the appendix was diagnosedon the basis of the findings of the histopathological examination.At autopsy, the gelatinous substance was found in both pleuralcavities, the right subphrenic area, and part of the large omentum.The case presented here is a very rare case of pseudomyxoniaperitonei, because dyspnea was the main feature and abdominalsymptoms such as abdominal distension and pain were lacking.Then high level of serum carcinoenibryonic antigen seen in thiscase is also pointed out.  相似文献   
74.
In 51 patients with primary lung carcinoma, correlations betweennuclear deoxyribonucleic acid (DNA) distribution patterns andpreoperative plasma carcinoembryonic antigen (CEA) levels wereinvestigated as nonmorphological, quantitative criteria forpredicting prognosis. Plasma CEA levels were determined withan Abbott enzyme immunoassay kit. The level of 5.0 ng/ml wasconsidered the upper limit of the normal value. Patients whoselung carcinoma had already established tumor stem line cellscarrying near-triploid (3c) or near-hexaploid (6c) DNA had higherpreoperative plasma CEA levels than did patients whose carcinoniasconsisted of diploid (2c), tetraploid (4c) or octaploid (8c)tumor cells. Plasma CEA values higher than 15.0 ng/ml occurredonly in the patients with near-3c or near-6c tumor stem linecells, never in the patients with 2c, 4c or Sc tumor stem cells.These results strongly indicate a distinct correlation betweennuclear DNA modal patterns and preoperative plasma CEA levelsin lung cancer patients.  相似文献   
75.
The mechanism of verapamil sensitive idiopathic left ventricular tachycardia (ILVT) is considered to be reentry. However, the nature of the reentry circuit, including the location of the slow conduction zone, is unclear. We sought the local electrical activity that would reflect slow conduction by precise mapping around the tachycardia exit (TE) in nine patients with ILVT (mean age, 28 ± 10 years) undergoing radiofrequency catheter ablation (RFCA). The TE was defined as the earliest discrete spiky potential (SP) recorded during the tachycardia, or as a complete configuration-matched pacemap 12-lead electrocardiogram (ECG). In all patients, the TE was located at the mid or inferior distal portion of the septum. The SP at the TE preceded the surface QRS by 20 ± 9 ms. The pacemap score at the TE was 11.4 ± 0.6 points. In three patients, fractionated potentials (FP) were recorded during the tachycardia. The onset of the FP preceded the surface QRS by 47 ± 8 ms and was earlier than the SP at the TE (P < 0.01). The sites where an FP was detectable were restricted to a small area, and were at a distance of 14 ±4 mm from the TE. The direction of the FP site from the TE was more basal in two patients and inferior in one, Pacemap ECGs at the sites with an FP showed poor matching (9 ± 1 points), presumably because of predominant capture of the local ventricular muscle rather than an electrically isolated reentry circuit. Successful RFCA was achieved at the site of the FP in all three patients in which one was recorded, and at the TE in the other six patients. The FP, which has been shown to reflect the slow conduction of the ventricular tachycardia circuit in structural heart disease, was also detected in ILVT in the present study, and it is likely to reflect electrical excitation of the distal rim of the slow conduction zone.  相似文献   
76.
77.
Tertiary structure of parathyroid hormone fragment (1–34) is predicted by the Monto Carlo simulated annealing method. Among the 20 structures obtained after completely unbiased calculations, the lowest-energy conformation exhibits two α-helices around residues 2–10 and 18–22. This structure agrees with the models, especially with the location of helices, deduced from experiments. In addition, the simulation supports empirical implications in the following two points. (1) The helix near the N-terminus is more stable than the C-terminal one. (2) The rest of the peptide segments are flexible and do not tend to have any definite structure. Our calculation correctly predicts only an α-helix, whereas previous analyses by the Chou–Fasman method leave an ambiguity between an α-helix and a β-strand.  相似文献   
78.
The plasma concentration profile, urinary excretion rate and diuretic response were studied in anaesthetized dogs after an intravenous administration of torasemide or furosemide. The urinary excretion rate of furosemide decreased rapidly after administration. The plasma concentration, which is related to the urinary excretion profile, also decreased rapidly. The diuretic response, which reflected the excretion rate, occurred rapidly after administration but lasted for a short time. The urinary excretion rate of torasemide was much lower than that of furosemide and decreased slowly after administration. The plasma concentration also decreased slowly. The diuretic response to torasemide occurred more slowly but lasted longer than the response to furosemide. These results suggest that the diuretic response profile of either diuretic depends on their urinary excretion rate, and that the difference in the diuretic response between torasemide and furosemide may be explained by the different transfer rate of the drugs from the plasma to the nephron.  相似文献   
79.
A case of cardiac foreign bodies leading to development of four varieties of automatic tachycardia is reported. A 51-year-old male with aortic regurgitation was admitted to our hospital because of palpitations. An electrocardiogram revealed junctional tachycardia with or without left bundle branch block, and two types of fascicular tachycardias. Computed tomography showed metallic foreign bodies from a fractured guidewire in the membranous portion of the interventricular septum, which was inadvertently retained when he underwent diagnostic cardiac catheterization at the age of 27.  相似文献   
80.
We report a case of primary testicular leiomyosarcoma. A 76-year-old man, who complained of left scrotal swelling for 6 months, underwent radical orchiectomy. Microscopic examination revealed intratesticular leiomyosarcoma. The patient received no adjuvant therapy and at 12 months after surgery, there had been no recurrence. Primary leiomyosarcoma of the testis is extremely rare; this is the 9th case recorded worldwide.  相似文献   
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