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971.
A case of midcervical diastematomyelia presenting as acute traumatic hemiplegia in an adult is discussed, with emphasis upon features reflecting this particular location. Advantages of metrizamide computed tomographic imaging in the diagnosis of this entity are presented, and a method of operative management is outlined.  相似文献   
972.
Three ring beta-secoestradiols, 2alpha,3beta- and 2beta,3beta-2-ethyl-3-(p-hydroxyphenyl)-6beta-methyl-trans-bicyclo[4.3.0]nonan-7beta-ols, have been synthesized and some of them shown to possess significant antiimplantation activity in rats.  相似文献   
973.
974.
AimsDryness of the mouth is one of the most distressing chronic toxicities of radiation therapy in head and neck cancers. In this study, parotid function was assessed in patients with locally advanced head and neck cancers undergoing intensity-modulated radiotherapy (IMRT) with or without chemotherapy. Parotid function was assessed with the help of a questionnaire and parotid scintigraphy, especially with regards to unilateral sparing of the parotid gland.Materials and methodsIn total, 19 patients were treated with compensator-based IMRT between February 2003 and March 2004. The dose to the clinical target volume ranged between 66 and 70 Gy in 30–35 fractions to 95% of the isodose volume. Ipsilateral high-risk neck nodes received an average dose of 60 Gy and the contralateral low-risk neck received a dose of 54–56 Gy. Eight of 19 patients also received concomitant chemotherapy.ResultsSubjective toxicity to the parotid glands was assessed with the help of a questionnaire at 0, 3 and 6 months and objective toxicity was assessed with parotid scintigraphy at 0 and 3 months. The mean dose to the ipsilateral parotid gland ranged from 19.5 to 52.8 Gy (mean 33.14 Gy) and the mean dose to the contralateral gland was 11.1–46.6 Gy (mean 26.85 Gy). At a median follow-up of 13 months, 9/19 patients had no symptoms of dryness of the mouth (grade I), 8/19 had mild dryness of the mouth (grade II) and only 2/19 had grade III xerostomia, although the parotid gland could only be spared on one side in most of the patients.ConclusionsMinimising the radiation dose to one of the parotid glands with the help of IMRT in patients with advanced head and neck cancers can prevent xerostomia in most patients and parotid scintigraphy is a useful method of documenting xerostomia.  相似文献   
975.
Serum sickness is a type III hypersensitivity reaction mediated by immune complex deposition with subsequent complement activation, small-vessel vasculitis, and tissue inflammation. Although the overall incidence of serum sickness is declining because of decreased use of heterologous sera and improved vaccinations, rare sporadic cases of serum sickness from nonprotein drugs such as penicillins continue to occur. Drug-induced serum sickness is usually self-limited, with symptoms lasting only 1-2 weeks before resolving. We report an unusual case of a severe and prolonged serum sickness reaction that occurred after exposure to an intramuscular penicillin depot injection (probable relationship by Naranjo score) and discuss how pharmacokinetics may have played a role. Clinicians should be familiar with serum sickness reactions particularly as they relate to long-acting penicillin preparations. Accurate diagnosis in conjunction with cessation of drug exposure and prompt initiation of antiinflammatory treatment with corticosteroids can produce complete recovery  相似文献   
976.
977.
In vivo corneal absorption of the dipeptide prodrugs of acyclovir (ACV) was evaluated using microdialysis in rabbits. A corneal well was placed on the cornea of the anesthetized New Zealand White rabbits with implanted linear probes into the aqueous humor. Two hundred microliters of a 1% solution of L-valine-ACV (VACV), glycine-valine-ACV (GVACV), valine-valine-ACV (VVACV), and valine-tyrosine-ACV (VYACV) was placed in the corneal well and was allowed to diffuse for a period of 2 h, following which the drug solution was aspirated and well removed. Samples were collected every 20 min throughout the infusion and postinfusion phases and were analyzed by HPLC to obtain the aqueous humor concentrations. Absorption rate constants of all the compounds were found to be lower than the elimination rate constants. GVACV exhibited highest absorption rate (ka) compared with other prodrugs, but all the prodrugs showed similar terminal elimination rate (lambda(z)). The time of maximum absorption (Tmax) of ACV after administration of VACV and the dipeptide prodrugs did not vary significantly (p < 0.05). GVACV exhibited the highest concentration (Cmax) and area under curve (AUC) upon absorption (p < 0.05) compared to VACV, VVACV, and VYACV. Dipeptide prodrugs of ACV were absorbed through the cornea at similar rates but to varying extents. The dipeptide prodrug GVACV owing to its enhanced absorption of ACV seems to be a promising candidate for the treatment of ocular HSV infections.  相似文献   
978.
979.
980.
Posttraumatic cerebrospinal fluid cyst of the orbit. Case report   总被引:1,自引:0,他引:1  
A 27-year-old man sustained a fracture of the orbital roof and a basofrontal dural tear in a motor-vehicle accident. One week later, he developed an orbitocranial dural fistula manifested by an orbital cyst, pulsatile proptosis, and serous drainage from the eye. Specific diagnosis was established only after computerized tomography metrizamide cisternography demonstrated direct communication of the orbital cyst with the subarachnoid space. The pertinent literature is reviewed.  相似文献   
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