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21.
The three-dimensional relationship between the acetabulum and femoral head was evaluated using three-dimensional computed tomography (CT) reconstruction before and after rotational acetabular osteotomy. This method provides exact anatomic information on acetabular coverage so that precise operative planning is more easily made. Evaluation of six dysplastic hips indicated the possible dangers of anterolateral rotational shift of the acetabulum when there is marked posterior deficiency, such as in the case of a high decree of subluxated femoral head covered by a shallow false acetabulum. In these circumstances, it may be safer and preferable to plan a lateral shift instead of an anterolateral shift.  相似文献   
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23.
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   
24.
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   
25.
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   
26.
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   
27.
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   
28.
Elective cesarean as a risk factor for transfusion after delivery of twins   总被引:1,自引:0,他引:1  
We examined deliveries of twins to identify factors most strongly associated with an increased risk of transfusion. We reviewed the obstetric records of 511 twin deliveries at the Japanese Red Cross Katsushika Maternity Hospital from 2003 through 2007. After 18 (3.5%) of these deliveries, transfusions were required. Transfusion was significantly more likely after elective cesarean delivery at a gestational aged of 37 weeks or more (odds ratio, 4.85; 95% confidence interval, 1.87-12.61). Emergency cesarean delivery (at > or =37 weeks' gestation) was not associated with an increased risk of transfusion. The delivery mode of twins should be carefully considered because of the increased risk of transfusion after elective cesarean delivery at a gestational age of 37 weeks or more.  相似文献   
29.
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   
30.
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   
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