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31.
Abstract: To prevent side effects from a silicone shim in Isshiki thyroplasty type I, we used a ceramic shim in 10 patients with unilateral recurrent laryngeal nerve paralysis. No published reports have described the use of ceramic in this type of surgery. According to the degree of glottic insufficiency, ceramic shims of various heights were inserted into the fenestration made in the thyroid ala. All patients experienced subjective improvement of voice postoperatively. Laryngoscopies in most cases showed that glottic insufficiency improved postoperatively. In the postoperative examination, the maximum phonation time improved an average of 3.7 s, and the mean flow rate improved an average of 331 ml/s. We have analyzed the relationship of these improvements to the degree of glottic insufficiency and have compared our results with those of other investigators.  相似文献   
32.
The lateral habenular nucleus of the rat contains a dense plexus of dopaminergic fibers, which are more marked in the medial part of the lateral habenular nucleus than in its lateral counterpart. Employing a combination of fluorescent retrograde axonal tracing with fluorogold and tyrosine hydroxylase immunofluorescence histochemistry, we investigated the distribution of cells of origin of the dopaminergic afferent fibers to the lateral habenular nucleus in the rat. The cells double-labeled with both fluorogold injected into the lateral habenular nucleus and tyrosine hydroxylase antisera were seen in a variety of fore- and midbrain regions, including the bed nucleus of the stria terminalis, medial preoptic area, periventricular, ventromedial, and dorsomedial hypothalamic nuclei, ventral tegmental area, interfascicular nucleus, substantia nigra pars compacta, ventrolateral division of the midbrain periaqueductal gray, and dorsal raphe nucleus. The double-labeled cells were located bilaterally with an ipsilateral predominance, and constituted approximately 10% of the total fluorogold-positive cell population. We have further observed by anterograde axonal tracing with Phaseolus vulgaris–leucoagglutinin that projection fibers arising from the sites of origin of the dopaminergic afferent fibers to the lateral habenular nucleus terminate mainly in the medial part of the lateral habenular nucleus, and to a lesser extent in its lateral conterpart. Thus, we have found in the present study that the dopaminergic neurons sending their axons to the lateral habenular nucleus are widely distributed in the A9, A10, A14, and A15 dopaminergic cell groups. Such dopaminergic neurons may exert regulatory influences upon many limbic-associated brain regions via the lateral habenular nucleus. © 1993 Wiley-Liss, Inc.  相似文献   
33.
Developments in the treatment of childhood cancer have beenevaluated in patients who had been treated in the National Children'sHospital from 1965 to 1987. The total number of patients was867, of which leukemia accounted for 376, malignant lymphoma61, neuroblastoma 174, Wilms' tumor 55, yolk sac tumor 29, rhabdomyosarcoma36 and hepatoblastoma 30. Patients were divided into three timeintervals: the 1960s, 1970s and 1980s. A marked improvementin five-year survival was recognized in Wilms' tumor and yolksac tumor, amounting to 80%, followed by rhabdomyosarcoma, acutelymphoblastic leukemia and malignant lymphoma. There was noimprovement in patients with acute non-lymphoblastic leukemia,neuroblastoma and hepatoblastoma. Prognostic factors for neuroblastomawere further analyzed, and the age of onset and stage of diseasewere found to have remained constant for 23 years. Factors relatingto the improvement of survival were discussed.  相似文献   
34.
Summary We describe two patients with sporadic amyotrophic lateral sclerosis (ALS), who had developed progressive external ophthalmoplegia of a predominantly supranuclear type while they survived on respirators, and displayed histopathological abnormalities both typical and atypical of ALS. Patient 1 was a 43-year-old man with ALS of 5-year duration, who had initially exhibited fulminant ALS, and remained on a respirator for 4 years. Patient 2 was a 51-year-old man with ALS of 13-year duration, who remained on a respirator for 8 years. Both patients died in a totally locked-in state. Autopsy of both patients revealed not only histopathological abnormalities consistent with ALS, but also multisystem degeneration which involved the pontine tegmentum, substantia nigra, Clarke's dorsal nuclei and spinocerebellar tracts. In addition, Patient 2 displayed intracyto-plasmic neuronal basophilic inclusion bodies which exhibited marked immunoreactivity to anti-ubiquitin antibodies. Our case reports indicate that the longer survival which is possible through the use of respirators may make one subgroup of ALS patients prone to develop atypical clinical and neuropathological features which are not observed during the natural cours of ALS.Supported by a Grant-in-Aid from the Research Committee of CNS Degenerative Diseases, the Ministry of Health and Welfare of Japan, and by a Grant from Nihon University School of Medicine, Tokyo  相似文献   
35.
Although anaphylactoid reactions to local anesthetics are well known, a radioallergosorbent test (RAST) to detect specific drug reagin (IgE) anti-body has not been developed. We established RAST for local anesthetics by using carboxylic acid derivatives of lidocaine, procaine and methylparaben. Serum samples were taken from 100 volunteers who were regarded to be nonallergic to the drugs used. Negative RAST values obtained from these volunteers were 1653 ± 254(SD) cpm (lidocaine), 2750 ± 264cpm (procaine), and 2805 ± 336cpm (methyl paraben).(Kokubu M, Oda K, Shinya N: Radioallergosorbent test (RAST) for specific IgE antibody to lidocaine, procaine and methylparaben. J Anesth 3: 74–79, 1989)  相似文献   
36.
Transient induction of single GST-P positive hepatocytes by DEN   总被引:12,自引:3,他引:9  
The single cells positive for placental glutathione S-transferase(GST-P), detectable in livers of rats soon after treatment withhepatocarcinogens, are possible ‘initiated cells’,the hypothesis tested in the present series of experiments.No low dose threshold was observed in male Sprague-Dawley ratsat different single doses of diethylnitrosamine (DEM) althougha plateau was reached between 160 and 200 mg/kg body weight.At the latter single dose 12 400 positive cells/cm3 were observedimmunohistochemically in rat livers after one week, the numbersthen decreasing to week 8 and thereafter rising again. In thenumbers then decreasing to week 8 and thereafter rising again.In the early stages single cells predominated but with timea gradual increase in mini-foci and larger lesions became evident.Application of selection pressure (feeding of diet containing0.02% 2-AAF plus partial hepatectomy) to rats 2–24 weeksafter single DEN-treatment resulted in the formation of largefoci positive for GST-P, especially in the early stages, thegrowth response being less pronounced with time. The numberof foci, on the other hand. was correlated with the number offoci, on the other hand, was correlated with the number ofsingle cells/mini-foci detected inhepatectomy tissue of thesame individuals. These results suggest that the early GST-Ppositive populations could be the precursor for preneoplasticfoci and nodules.  相似文献   
37.
Classical citrullinemia (CTLN1), a rare autosomal recessive disorder, is caused by mutations of the argininosuccinate synthetase (ASS) gene, localized on chromosome 9q34.1. ASS functions as a rate-limiting enzyme in the urea cycle. Previously, we identified 32 mutations in the ASS gene of CTLN1 patients mainly in Japan and the United States, and to date 34 different mutations have been described in 50 families worldwide. In the present study, we report ASS mutations detected in 35 additional CTLN1 families from 11 countries. By analyzing the entire coding sequence and the intron-exon boundaries of the ASS gene using RT-PCR and/or genomic DNA-PCR, we have identified 16 novel mutations (two different 1-bp deletions, a 67-bp insertion, and 13 missense) and have detected 12 known mutations. Altogether, 50 different mutations (seven deletion, three splice site, one duplication, two nonsense, and 37 missense) in 85 CTLN1 families were identified. On the basis of primary sequence comparisons with the crystal structure of E. coli ASS protein, it may be concluded that any of the 37 missense mutations found at 30 different positions led to structural and functional impairments of the human ASS protein. It has been found that three mutations are particularly frequent: IVS6-2A>G in 23 families (Japan: 20 and Korea: three), G390R in 18 families (Turkey: six, U.S.: five, Spain: three, Israel: one, Austria: one, Canada: one, and Bolivia: one), and R304W in 10 families (Japan: nine and Turkey: one). Most mutations of the ASS gene are "private" and are distributed throughout the gene, except for exons 5 and 12-14. It seems that the clinical course of the patients with truncated mutations or the G390R mutation is early-onset/severe. The phenotype of the patients with certain missense mutations (G362V or W179R) is more late-onset/mild. Eight patients with R86H, A118T, R265H, or K310R mutations were adult/late-onset and four of them showed severe symptoms during pregnancy or postpartum. However, it is still difficult to prove the genotype-phenotype correlation, because many patients were compound heterozygotes (with two different mutations), lived in different environments at the time of diagnosis, and/or had several treatment regimes or various knowledge of the disease.  相似文献   
38.
This study was conducted to quantify the change in the number and size of myelinated nerve fibers of the maxillary nerve with tooth loss in humans. We carried out a morphometric analysis to compare the number and size of myelinated nerve fibers in the human maxillary nerve between four dentulous and four edentulous jaw cases. Our results indicated that the number of axons decreased by approximately 13,000 with tooth loss. The average size of axons remained unchanged, but there was a change in the fiber size distribution, namely the loss of a large number of small-sized axons was accompanied by the total disappearance of small number of large-sized axons.  相似文献   
39.
All of the five commercially available benzylpenicillin preparations obtained from different sources and a PcG preparation prepared by filtration of a commercial PcG on Sephadex G10 elicited the systemic anaphylactic reactions in guinea pigs which had been immunized with benzylpenicilloyl (BPO)-Ascaris extract conjugate (BPO-As) mixed with aluminum hydroxide gel. These preparations could evoke no such reactions in guinea pigs immunized with BPO-bovine gamma globulin conjugate (BPO-BGG) emulsified with complete Freund's adjuvant. The severity of the systemic anaphylactic reactions correlated significantly with the titers of either 8-day passive cutaneous anaphylactic (8-day PCA) reactions or 4-hr PCA reactions evoked with the same benzylpenicillin preparations. In vitro benzylpenicillin preparation contracted the tracheas of the guinea pigs immunized with BPO-As. These results indicated that the commercially available benzylpenicillin preparations have enough antigenicity to evoke systemic anaphylactic reactions in guinea pigs immunized with BPO-As mixed with aluminum hydroxide gel. Such guinea pigs represent an animal model for investigation of penicillin allergy.  相似文献   
40.
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