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991.
992.
Measurements of respiratory mechanics are frequently made in ventilated infants and children. Esophageal pressure measurements (Pes using a balloon on a catheter have been used to partition the respiratory mechanics into lung and chest wall components. Appropriate positioning of this balloon is crucial to obtain accurate estimates of pleural pressure. Traditionally, in spontaneously breathing subjects the balloon position is assessed with an occlusion test. In ventilated subjects, it is not always possible to perform an occlusion test prior to paralysis, and even if such a test is performed it may not be relevant under conditions of positive pressure ventilation. We have assessed a positive pressure occlusion test that is suitable for paralyzed subjects. By occluding the airway opening and applying gentle pressure to the abdomen or rib cage, positive swings in pressure can be measured by both Pes and airway opening pressure (Pao). We compared traditional occlusion tests measured in 16 spontaneously breathing puppies to the positive pressure occlusion test performed after paralysis. In 2 pups we were unable to obtain a reasonable traditional occlusion test (>15% difference between Pes and Pao) but we obtained 10 traditional occlusion tests in each of the remaining 14 pups (2.1–14 kg). In 11 of these animals Ape, was within 10% of Pao. This compared well to positive pressure occlusion test using abdominal pressure performed after paralysis, where Apes was within 10% of ΔPao in 10 animals. In 9 of these pups occlusion tests were also performed by applying pressure on the rib cage, where ΔPes was within 10% of ΔPao in 6 animals. These results suggest that it is possible to perform accurate occlusion tests in paralyzed subjects by abdominal or rib cage compression with the airway occluded. Pediatr Pulmonol. 1994; 17:56–62. © 1994 Wiley-Liss, Inc.  相似文献   
993.
The neuro-ophthalmological manifestations of 20 patients with the syndrome of ophthalmoplegia, ataxia and areflexia are described. The symmetrical nature of the ophthalmoplegia and the associated cerebellar ataxia point to centrally placed lesions. Several supranuclear, nuclear and internuclear ophthalmological signs are identified. Some of these, like partial sparing of the levator palpebrae and normal downgaze in the presence of severe ophthalmoplegia are noted too frequently to be just unusual signs of peripheral oculomotor dysfunction. Other identified features included upper lid retraction on attempted upgaze and preserved Bell's phenomenon in the presence of paralysis of the latter, as well as several other central ophthalmological signs. These findings contrast with those seen in the Guillain-Barré syndrome and, thus, the syndrome of ophthalmoplegia, ataxia and areflexia is not a mere variant of it.  相似文献   
994.
An electron microscopic study was done on abductor pollicis brevis muscles of 18 Rhesus monkeys after intramuscular injections of 0.75% bupivacaine, 2% mepivacaine, or 2% lidocaine + epinephrine. The muscles were examined for from 2 h to 28 days. Severe muscle fiber damage, consisting of breakdown of sarcolemma and myofibrils, was seen as early as 2 h. Phagocyte mediated fragmentation of the degenerating muscle fibers was at its peak during the third and fourth days. Myoblasts were abundant during the fourth day. Early myotubes appeared on the fifth and sixth days, and they matured during the second week. Satellite cells appeared alongside mature myotubes. Overall, the local anesthetic-induced breakdown and regeneration of skeletal muscle fibers in the monkey followed a course quite similar to that seen in the rat.  相似文献   
995.
Diagnosis of fetal rubella infection by nucleic acid hybridization   总被引:4,自引:0,他引:4  
The efficacy of nucleic acid hybridization for the diagnosis of rubella infection in experimental and clinical materials was compared with immunoblot and virus isolation techniques. Our results showed that nucleic acid hybridization is specific and rapid but gives false-negative results when compared with conventional virus isolation in some experimental although not in clinical materials so far examined. For this reason, a failure to demonstrate rubella virus in fetal specimens by this method alone cannot yet be taken as a sole criterion for ruling out fetal rubella infection.  相似文献   
996.
997.
Objective Report of two cases of exudative discoid and lichenoid dermatosis (Sulzberger-Garbe), with typical penile lesions. Differential diagnosis of persistent penile plaques. Background Following remission of the generalized eruption of exudative discoid and lichenoid dermatosis (Sulzberger-Garbe), it is not unusual to see a single remaining lesion localized on the penis. Since Sulzberger et al. (Sulzberger MB, Witten VH, Hunt JA. Puzzling persistent penile plaques. Arch Dermatol 1956:73:101-109) reviewed dermatoses presenting with puzzling persistent penile plaques in 1955, further dermatoses have evolved as important differential diagnoses. Much controversy has arisen as to the justification of exudative discoid and lichenoid dermatosis (Sulzberger-Garbe) as a disease entity. Conclusions Diagnosis of most cases of persistent plaques of dermatitis on the penis is possible with a careful examination of the entire skin, and a thorough history to discover past lesions. The possibility of malignancy makes a biopsy mandatory. Exudative discoid and lichenoid chronic dermatosis (Sulzberger-Garbe) typically responds well to systemic steroids. Intrale-sional triamcinolone acetonide has been demonstrated to be effective in the treatment of a persistent penile plaque in exudative discoid and lichenoid dermatosis (Sulzberger-Garbe), and may be helpful in discontinuing or reducing systemic therapy to a level compatible with long-term treatment.  相似文献   
998.
高位食管癌切除颈部胃食管重建术的临床应用和初步评价   总被引:1,自引:0,他引:1  
本文报道了我院自1988年至1994年间采用高位食管癌切除颈部胃食管重建术治疗高位食管癌23例的结果,其中男14例,女9例,年龄35-70岁,平均年龄52岁,病变位于颈段者11例,上胸段者12例。2,3,5年生存率分别为62.5%,55.1%,33.3%。同时介绍了手术要点和该术式的优点,并提出了吻合口瘘的预防措施。  相似文献   
999.
50种传统清热解毒药的抑菌实验   总被引:13,自引:1,他引:12  
华娟  周明康 《中药材》1995,18(5):255-258
本文报告了传统药物文献收载的50种清热解毒药的抑菌实验结果。显示抑菌作用的有41种,占82%。对阳性球菌显示有抑菌作用的有36种;对阴性杆菌显示有抑菌作用的有24种。其中的地胡椒、金果榄、毛果算盘子等显示有较广的抗菌效应,值得进一步研究。  相似文献   
1000.
In this study, large areas of goldfish telencephalon were ablated including rostral nucleus preopticus periventriculare (rNPP), and degenerating axons were traced by a modified Fink and Heimer procedure. The lesioning procedure ablated large regions of area dorsalis telencephali pars medialis, centralis, and dorsolateral complex; and completely removed area ventralis telencephali pars dorsalis, ventralis, and lateralis. In addition, the supracommissural nucleus and rNPP were lesioned specifically because both nuclei have been thought to be involved in courtship behavior and endocrine control of reproduction. This investigation demonstrated extensive fiber projections from telencephalic nuclei and/or rNPP to the hypothalamus. Lesioned telencephalon and/or rNPP projected bilaterally to nucleus preopticus and the suprachiasmatic nucleus and unilaterally to the following tuberal nuclei: nucleus anterior tuberis, and the lateral hypothalamic nucleus. A much larger fiber projection to the inferior lobe nuclei was also observed with a large contralateral as well as ipsilateral input.  相似文献   
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