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61.
Several commercial pilocarpine preparations have been compared for their efficacy of drug delivery as evaluated by changes in pupil diameter, and return to base-line pupil size, in rabbits and squirrel monkeys. Adsorbocarpine, Isoptocarpine, Pilocar, all at 2%, and Pilopine HS gel, 4%, were used. In albino rabbits the order of efficacy, as judged by area under the curve, or maximal pupil diameter change, was Pilopine greater than Isoptocarpine = Adsorbocarpine greater than Pilocar = saline (prepared in this laboratory). In general, greater areas under the curve were associated with greater changes in pupil diameter. Pupil diameter had returned to normal by a maximum of 5 hours after drop instillation. In squirrel monkeys, the maximum pupillary change was statistically (P greater than 0.05) the same for all preparations, as was the percentage change in pupil diameter at 6 hours since pupils were still somewhat constricted at this time after drop instillation. The differences in area under the curve were minor. The greater response in primates compared to rabbits may be due to differences in pigment, intraocular kinetics and a far more active ciliary muscle in primates. Also studied were newly developed, non-surfactant containing, preservative-free polymer- and microparticle-based vehicles. Some of the vehicles, based on cyanoacrylate, modified hyaluronate, anionic copolymers, polyvinyl-pyrrolidone, cross-linked gelatin and microparticles showed greater pupillary changes and areas under the curve in rabbits compared to saline vehicle. When compared to commercial preparations in the monkey eye cyanoacrylate block copolymer and modified hyaluronate showed an increase in efficacy. Polyvinylpyrrolidone, anionic copolymer and cross-linked gelatin were equal to the commercial preparations.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
62.
The experience with the treatment of malignant histiocytosis has been disappointing. Despite modest treatment success with a combination of cyclophosphamide, Adriamycin (doxorubicin), vincristine and prednisone, the overall prognosis remains poor. There are only a few reports of prolonged complete remissions in pediatric patients. The following report describes two children who have had long-term remission with an aggressive combination chemotherapy program that included intrathecal prophylaxis. The chemotherapeutic regimen described merits further evaluation in a larger number of patients. 相似文献
63.
Y. O’Meara A. Green M. Carmody G. Doyle J. Donohoe 《Irish journal of medical science》1989,158(12):300-303
Twenty five patients with renal vasculitis presenting over an eight year period were reviewed. Ten had microscopic polyarteritis,
6 classic polyarteritis, 5 overlap syndrome, 2 Churg-Strauss syndrome and 2 Wegener’s granulomatosis. Clinical features included
hypertension, pulmonary involvement, neurological involvement and arthralgia. Serum creatinine was over 500 umol/1 in 13 patients,
10 of whom required dialysis. Visceral angiography was positive in 80% of those studied, Focal and segmental necrotising glomerulonephritis
was the commonest renal lesion. Treatment consisted of corticosteroids and cytotoxic agents in most cases. Plasmapheresis
was used for rapidly progressive renal failure, severe pulmonary haemorrhage or cerebral vasculitis. Improvement or stabilisation
of renal function was seen in 68% of patients treated. There were 4 early deaths and one late death. The diagnosis, histology,
treatment and outcome of renal vasculitis is discussed. The importance of early diagnosis and treatment is emphasised in this
potentially reversible cause of acute renal failure. 相似文献
64.
The Ca antigen has been reported to be present on the surface of malignant but not, with few exceptions, non-malignant cells. We investigated the potential usefulness of the monoclonal Ca 1 antibody in differentiating oral squamous cell carcinoma from non-malignant or premalignant oral neoplasms. Paraffin-embedded sections from 33 biopsy specimens of 12 hyperplastic and 21 neoplastic oral lesions were examined by immunohistochemical staining. Seven of the 33 specimens showed positive staining for Ca antigen. Fifteen of 21 specimens of oral squamous cell carcinoma were negative for Ca antigen, and one case of focal keratosis was positive. The results indicate that the use of the Ca 1 antibody to distinguish oral squamous cell carcinoma from non-malignant or premalignant oral lesions is highly unreliable. 相似文献
65.
Long-term effects of cochlear implants in children. 总被引:5,自引:0,他引:5
Susan B Waltzman Noel L Cohen Janet Green J Thomas Roland 《Otolaryngology--head and neck surgery》2002,126(5):505-511
OBJECTIVE: Since 1987, when the use of multichannel cochlear implants was initiated in children, candidacy has expanded; many thousands of children have received these devices, and results have revealed a wide range of performance. However, few long-term studies exist on a large population of these children. There have been concerns expressed that cochlear implant function might degrade over time, that devices and electrodes might migrate and extrude in the growing child, or that there might even be a deleterious effect of long-term stimulation of the cochlear nerve. The purpose of this study was to explore the long-term effects of implantation as a function of performance over time, reimplantation, and educational factors. STUDY DESIGN AND SETTING: We studied 81 children who received implants at a major academic medical center and were followed for 5 to 13 years. RESULTS: Results revealed significant gains in speech perception, use of oral language, and ability to function in a mainstream environment. There was no decrease in performance over time and no significant incidence of device or electrode migration or extrusion, and device failure did not cause a deterioration in long-term outcome. CONCLUSIONS: Multichannel cochlear implants in children provide perception, linguistic, and educational advantages, which are not adversely affected by long-term electrical stimulation. 相似文献
66.
67.
68.
OBJECTIVE: Schizophrenic patients typically perform poorly on the Wisconsin Card Sorting Test, which is a putative index of prefrontal functioning. The authors attempted to remediate the deficits of schizophrenic patients on this measure by giving detailed instructions and monetary reinforcement. METHOD: Forty-six inpatients with chronic schizophrenia and 20 control subjects with other psychiatric illnesses were given the Wisconsin Card Sorting Test under four conditions that varied in monetary reinforcement and level of instructions. The schizophrenic patients were given the Brief Psychiatric Rating Scale (BPRS) and three information processing measures (the Continuous Performance Test, Span of Apprehension, and Pin Test). RESULTS: Schizophrenic patients performed worse than psychiatric control subjects across most conditions. Monetary reinforcement had little effect on performance, but detailed instructions significantly improved the scores for both groups. When instructions were withdrawn and monetary reinforcement was maintained, both groups continued to show improved performance over baseline. Symptoms were not significantly associated with Wisconsin Card Sorting Test performance. One measure (the Pin Test) correlated significantly with performance on the Wisconsin Card Sorting Test. CONCLUSIONS: The results suggest the importance of combining motivational with instructional factors for training psychiatric patients in problem solving. 相似文献
69.
Rebecca Knight MD Erick R Ratzer MD FACS Michael E Fenoglio MD FACS John T Moore MD 《Journal of the American College of Surgeons》1997,185(5):481-485
Background:Most abnormal parathyroid glands can be removed through a standard cervical incision; even those in the superior mediastinum. Those located in certain areas of the mediastinum, for example posteriorly or in the aortopulmonic window, historically have required excision through a median sternotomy or thoracotomy. Angioablation is a nonsurgical alternative to management of these lesions.Study Design:We present two case reports of mediastinal parathyroid adenomas that were excised thoracoscopically, and review the literature regarding the management of mediastinal parathyroid adenomas.Results:Both patients who underwent precise localization and thoracoscopic excision of their mediastinal parathyroid adenomas had resolution of their hypercalcemia with minimal associated morbidity and shortened recovery periods.Conclusions:We suggest that thoracoscopic excision of mediastinal parathyroid adenomas is the better means of controlling hypercalcemia secondary to parathyroid adenoma in those patients considered for either median sternotomy, thoracotomy or angiographic ablation where the exact location of the lesion can be established preoperatively. 相似文献
70.