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991.
992.
Centrally Dampening Drugs, II: 3-Substituted 4-Hydroxypyrimido[1,2-a]benzimidazol-2-ones The 4-hydroxypyrimido[1,2-a]benzimidazol-2-ones 3a–g obtained by reacting 2-aminobenzimidazole (1) with the malonic acid esters 2a–g exhibit centrally dampening, hypertensive, fungicidal, and antibacterial properties.  相似文献   
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The ultrastructure ofToxocara canis eggs is described before and after exposure to microwaves. The morphology of normal eggs is compared to that of eggs from other helminths. Following treatment, the complete disorganization of the surface structure of the shell and the loss of much turgidity of the egg are observed. The destruction of the internal structure is most marked in the center of the egg and is associated with the disappearance of some layers of the shell. In addition, there is substantial damage to the synthesis apparatus (ribosomes, endoplasmic reticulum, lipid cisternae). An explanation based on the specific action of microwaves and micro-overheating is proposed, and the prophylactic use of this technique is considered.  相似文献   
995.
Three cases of spontaneous extracranial vertebral artery dissection   总被引:3,自引:0,他引:3  
We describe three cases of extracranial vertebral artery dissection that are unusual in both their modes of presentation and their associations with other pathologic conditions. The first patient had Marfan's syndrome and migraine; his dissection was asymptomatic and was diagnosed by chance at the time of repeat angiography following a previous internal carotid artery dissection. The second patient had systemic lupus erythematosus and presented with a subarachnoid hemorrhage attributed to an intracranial vertebral artery dissection by the demonstration of an extracranial dissection. The third patient had a minor basilar artery stroke in which dissection had occurred beside a congenital hemivertebra deformity.  相似文献   
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BACKGROUND AND PURPOSE: Post-operative radiotherapy is indicated for the treatment of head and neck cancers. In vitro, chemotherapy potentiates the cytotoxic effects of radiation. We report the results of a randomized trial testing post-operative radiotherapy alone versus concomitant carboplatin and radiotherapy for head and neck cancers with lymph node involvement. MATERIALS AND METHODS: The study involved patients undergoing curative-intent surgery for head and neck cancers with histological evidence of lymph node involvement. Patients were randomly assigned to receive radiotherapy alone (54-72Gy, 30-40 fractions, 6-8 weeks) or identical treatment plus concomitant Carboplatin (50mg/m(2) administered by IV infusion twice weekly). RESULTS: Between February 1994 and June 2002, 144 patients were included. With a median follow-up of 106 months (95% confidence interval (CI) [92-119]), the 2-year rate of loco-regional control was 73% (95% CI: 0.61-0.84) in the combined treatment group and 68% (95% CI: 0.57-0.80) in the radiotherapy group (p=0.26). Overall survival did not differ significantly between groups (hazard ratio for death, 1.05; 95% CI: 0.69-1.60; p=0.81). CONCLUSIONS: Twice-weekly administration of carboplatin concomitant to post-operative radiotherapy did not improve local control or overall survival rates in this population of patients with node-positive head and neck cancers.  相似文献   
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