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71.
A case of a 53-year-old male with development of myosarcomaat the site of thorotrast injection is described. Thorotrastwas injected 29 years ago for the preoperative angiographicexamination of brain injury when there was an accidental extravasationof the contrast medium. Recently, a firm tumor was detected in the left side of theneck but without causing any disturbance to swallowing or breathing.Biopsy examination revealed myosarcoma with deposition of thorotrastin the surrounding tissue. Roentgenographic examination of theabdomen also showed deposition of thorotrast in the spleen andupper abdominal lymph nodes.  相似文献   
72.
Although the prime importance in treatment of head and neckcancer is eradication of tumors, due attention should be paidto the conservation of many important structures and functionsin the region. Just to mention a few of these important humanfunctions, there are phonation, digestion and facial expression.Simple surgical procedures specialized by otolaryngologistsare no longer satisfactory. Recently, radiotherapy of head and neck cancer has developedto a superlative degree and chemotherapy to a practical degreealthough much still remains to be satisfied. Our aim was toorganize an interdisciplinary group of specialists in surgery,radiotherapy and regional chemotherapy into a composite attackforce. We aimed at most effective treatment with the least ofside effects. Since 1961, our combined approach to cancer of the head andneck in close collaboration with radiotherapists has yieldedmuch improved results. This has led to an increasing numberof patients with satisfactory rehabilitation.
  1. 1. Cancer of the maxilla: Even in the advanced cases combinedsurgery, radiotherapy and regional chemotherapy has led to thepreservation of important structures and functions. Many patientsare now allowed to return to social life and to their previousjobs.
  2. 2. Cancer of the nasopharynx: Radiotherapy is the firstchoice.When the effect is less satisfactory, chemotherapy anda window-operationof the palate are performed.
  3. 3. Tumorsof the tonsils: The majority of patients suffer fromthe reticulumcell sarcoma. Radiotherapy is the first choice.
  4. 4. Cancerof the larynx: A full dose of radiotherapy is thefirst choice.Partial resections are done when indicated.
  5. 5. Cancer of thetongue, hypopharynx and esophagus: Radiotherapyis the firstchoice in the majority of cases. Some need plasticsurgery.
  相似文献   
73.
Autologous marrow was collected from patients with acute leukemiaduring their first remission, and cryopreserved. In relapse,four of the patients were treated with remission-induction chemotherapymore intensive than the previous treatment, followed by infusionof the cryopreserved autologous marrow. Autologous marrow infusioncaused relatively rapid hematological recovery from the bonemarrow depression induced by high-dose chemotherapy. All fourpatients achieved a second complete remission, but with no maintenancetherapy leukemic relapses were observed in three of them. Onepatient survived without leukemic relapse for 19 months, 13months longer than the previous remission period. Another effectof autoinfusion was reduction in blood products required duringthe bone marrow depression. These observations suggest thatcryopreserved autologous marrow may retain its hemopoietic activityand autologous marrow infusion may be effective in providingearly recovery or rescue from bone marrow failure.  相似文献   
74.
Gene therapy is defined as the treatment of diseases by the transfer of genes into patients. Clinical trials of gene therapy became feasible as a result of the development of retroviral mediated gene transfer techniques. The first trial was begun in September 1990 at the National Institutes of Health when a four year old girl was treated for adenosine deaminase deficiency. Currently, more than 500 patients are being treated by this innovative therapeutic strategy. In the present review article, the basic concepts and present status of human gene therapy are summarized.  相似文献   
75.
Thrombosis of the innominate vein and SVC is a serious complication in patients with pacemakers, inducing puhnonary embolism or SVC syndrome. Venography is the definitive method for its diagnosis; however, it is too invasive for related studies. The purpose of this study was to validate sonography, pulse Doppler, and color flow in detecting noninvasively innominate vein or SVC thrombosis in patients with pacemakers. In 53 patients with pacemakers, the 1 severe SVC stenosis and 18 severe innominate vein stenoses due to thrombosis were diagnosed by digital subtraction angiography. Sonography accurately showed the severe SVC stenosis due to thrombosis, but had limitations on the innominate vein thrombosis. Color flow demonstrated mosaic flow, indicating poststenotic turbulence due to stenosis of the innominate vein and SVC caused by thrombosis in 15 of 16 patients, and pulse Doppler disclosed absence of flow due to complete occlusion of the innominate vein in 2 of 2 patients. Sensitivity and specificity for detecting severe innominate vein stenosis due to thrombosis using combined color flow and pulse Doppler was 94% and 100%, respectively. In conclusion, sonography, pulse Doppler, and color flow allow accurate detection of severe innominate vein or SVC stenosis due to thrombosis, and are therefore useful for the follow-up of patients with a pacemaker.  相似文献   
76.
Abstract The effects of a novel histamine H2 receptor antagonist (FRG-8813) on the restoration process of gastric epithelial wounds were assessed using an in vitro wound healing model. FRG-8813 (1, 10 mol/L) was added to a complete confluent monolayer cell sheet after artificial wounding. The restoration process was analysed by a time-lapse video system and cell migration, proliferation and apoptosis were assessed. Hydrogen peroxide (1, 3 mmol/L) inhibited restoration after wounding by suppressing cell migration and proliferation and induced epithelial cell apoptosis around the wound. The addition of FRG-8813 abolished the hydrogen peroxide-induced retardation and prevented apoptosis, although FRG-8813 itself did not enhance wound healing. FRG-8813 may act as a radical scavenger as well as having an anti-secretory action and may have favourable effects on peptic ulcer healing.  相似文献   
77.
Stem bromelain was cleaved with cyanogen bromide, and the products were fractionated with and without prior maleylation and sulfitolysis. The fragments that corresponded to the carboxyl-terminal half of the molecule were isolated and nearly completely sequenced. This portion of the enzyme molecule contained one disulfide linkage. A specific cleavage at the amino peptide bonds of that cystine residue by reduction, modification into S-cyano derivatives and exposure to alkali gave important information of the amino terminal sequence. By combining the present data with the previously known partial sequence of the parent molecule, 101 amino acid residues were aligned down to the carboxyl terminus and compared with those of papain. The sequence homology between carboxyl-terminal halves of these two thiol proteases of plant origin was found to be 34.7%.  相似文献   
78.
79.
Separation of protected epimeric peptides, Z-Gly-Xaa-Xbb-OMe (where Xaa and Xbb = chiral amino acid residues), by reversed-phase HPLC was utilized for studying racemization in peptide synthesis. Thus, the following factors which might affect the extent of racemization during the coupling by the carbodiimide method were investigated: the combination of amino acid residues to be coupled, coexisting tertiary amine salts, and the relative configuration of the amino acid residues. The following points were revealed: the combination of bulky residues at the coupling site results in extensive racemization in a polar solvent such as DMF, the amine hydrochlorides cause less racemization than the p-toluenesulfonates in DMF, and the influence of relative configuration differs depending on the solvent and the individuality of the amino components. Furthermore, the racemization-suppressing effect of some additives in the carbodiimide method was reevaluated by employing the same procedure.  相似文献   
80.
Long-Term Evaluation of the Ventricular Defibrillation Energy Requirement   总被引:1,自引:0,他引:1  
Defibrillation Energy Requirements. Introduction : Defibrillation energy requirements in patients with nonthoracotomy defibrillators may increase within several months after implantation. However, the stability of the defibrillation energy requirement beyond 1 year has not been reported. The purpose of this study was to characterize the defibrillation energy requirement during 2 years of clinical follow-up.
Methods and Results : Thirty-one consecutive patients with a biphasic nonthoracotomy defibrillation system underwent defibrillation energy requirement testing using a step-down technique (20, 15, 12, 10, 8, 6, 5, 4, 3, 2, and 1 J) during defibrillator implantation, and then 24 hours, 2 months, 1 year, and 2 years after implantation. The mean defibrillation energy requirement during these evaluations was 10.9 ± 5.5 J, 12.3 ± 7.3 J, 11.7 ± 5.6 J, 10.2 ± 4.0 J, and 11.7 ± 7.4 J, respectively ( P = 0.4). The defibrillation energy requirement was noted to have increased by 10 J or more after 2 years of follow-up in five patients. In one of these patients, the defibrillation energy requirement was no longer associated with an adequate safety margin, necessitating revision of the defibrillation system. There were no identifiable clinical characteristics that distinguished patients who did and did not develop a 10-J or more increase in the defibrillation energy requirement.
Conclusion : The mean defibrillation energy requirement does not change significantly after 2 years of biphasic nonthoracotomy defibrillator system implantation. However, approximately 15% of patients develop a 10-J or greater elevation in the defibrillation energy requirement, and 3% may require a defibrillation system revision. Therefore, a yearly evaluation of the defibrillation energy requirement may he appropriate.  相似文献   
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