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21.
Seven cases of granular cell Abrikossoff tumours of the larynx and tongue are reported: four in the tongue and three in the larynx. All of these tumours were removed with the carbon dioxide (CO2) laser. The anatomical site of the origin and clinical features of granular cell tumours (GCT) are not specific. Histological, light microscopic, electron microscopic (EM) and immunohistochemical studies are required for diagnosis. The histogenesis and cellular derivation of GCTs is still controversial. The biological potential and lack of cellular atypia define a benign process. However, it is important to take into account that these tumours have ill-defined borders without a capsule. Radiation therapy has proved ineffective in the past. Surgical excision with a wide margin is required. Because of numerous advantages, for example, no bleeding, no oedema, minimal pain and quick recovery, CO2 laser removal is the treatment of choice. The authors have not seen any recurrence or complications.  相似文献   
22.
Summary The effects of hyperthermia on blood flow and oxygen consumption of the tongue were investigated in anesthetized dogs. For comparison, blood flow through the skin and deep muscle of the hind leg was also measured in some animals. Increasing blood temperature revealed a biphasic response of lingual blood flow. At 41°C blood temperature respiratory frequency was twice that of control and there was a reduction of lingual blood flow, while resistance of the lingual bed was increased significantly. The arterio-venous oxygen difference (AVDO2) of lingual blood was markedly increased at this level and the of the tongue was like-wise significantly greater than control. At 41.9°C, the steep increase of respiratory frequency was accompanied by a marked fall in lingual resistance as evidenced by a four-fold increase of lingual blood flow. The systemic AVDO2 rose at this temperature, while the lingual AVDO2 fell dramatically. There was no further increase of lingual . At both temperature levels the blood flow through the skin did not change substantially, while the deep muscle blood flow slightly increased. The mean arterial pressure showed a progressive fall during hyperthermia. It is assumed that the decrease of lingual blood flow at elevated blood temperature without panting is due to a redistribution of cardiac output to areas other than the tongue. The increase of lingual blood flow without an additional increase of lingual during panting may be explained solely as a mechanism for heat dissipation. The fact that the decrease of lingual resistance was demonstrated in immobilized animals concomitant with high frequency phrenic burst activity suggests that the decrease of lingual resistance and panting may be induced by a common central integrating mechanism.  相似文献   
23.
用免疫酶组化染色ABC法,研究了3例狂犬病人舌及3例涎腺中狂犬病毒抗原(RVAg)的分布。在2例4/5舌切片中见其浆液腺细胞、末梢神经、少数横纹肌纤维及复盖上皮包括味细胞中含大量RVAg颗粒,1例舌切片中无浆液腺,为阴性反应。在3例4/9大涎腺切片中只在腺叶内或末梢神经有少量弱反应的RVAg。与以往报告的病犬、狐、臭鼠大涎腺中含大量RVAg不同。人大涎腺中RVAg含量远比舌中为少。人舌浆液腺区可能是RVAg多见部位,可能是一传染源。  相似文献   
24.
Nie X 《Anatomy and embryology》2005,210(2):125-132
The Fgf/Fgfr (Fgf receptor) and Bmp signal pathways are critical for embryonic development and postnatal growth. In order to address their roles in tongue development, preliminary study of expression patterns of some important members in the two families, as well as of apoptosis and proliferation, were carried out in mouse developing tongue. Apoptosis in tongue is a very late event in embryogenesis, restricted to the upper layer of the epithelium whereas proliferation is very vigorous at the early stage of tongue development and remains active throughout embryogenesis. Bmp2, −4 and -5 were localized within the mesenchyme at the early embryonic stage of tongue development (E12 to E13), whereas Bmp3 and Bmp7 were mainly expressed in the epithelium. Most of these molecules were also seen in the tongue muscles at postnatal stages. Among Fgfr isoforms, Fgfr1c, −2b, and -2c were detected in embryogenesis with peak expression at E11 to E13. Fgfr1c and Fgfr2c were localized within the mesenchyme, while Fgfr2b was mainly expressed in the epithelium. High expression of Fgf7 and Fgf10 was also detected in the mesenchyme at the early embryonic stage of tongue development, corresponding to the Fgfr expression, suggesting that they are among the principal ligands functioning at the early embryonic expanding stage. Fgf2 was seen in the tongue muscles at the late embryonic and postnatal stages. These results suggest that Bmp and Fgf signalling regulates tongue development at multiple stages, possibly related to proliferation and differentiation.  相似文献   
25.
舌鳞癌术后颈部区域淋巴结的分析研究   总被引:4,自引:1,他引:4       下载免费PDF全文
目的:分析舌鳞癌颈淋巴结转移的发生规律,探讨舌癌特别是 cNo(临床不怀疑转移)患者的治疗原则。 方法: 通过对1985-2003年199例舌癌患者进行舌颌颈联合根治术的临床病理资料进行回顾性研究。 结果: 舌鳞癌的总体转移率为42.14%,cNo患者的颈淋巴结隐匿性转移率为26.83%,舌鳞癌的隐匿性转移与肿瘤TNM分期等密切相关。 结论: 临床上应根据原发灶的大小等综合考虑分析,选择合理的治疗方案。  相似文献   
26.
The effects of environmental constraints upon licking patterns   总被引:1,自引:0,他引:1  
Rats licked water under three degrees of environmental constraint. As restriction decreased, lick duration increased. Interlick interval changed independently of duration. Lickometer-measured drinking tube contact was longer than fluid contact unless access was highly restricted. The use of controlled access to measure minimal necessary taste input is discussed.  相似文献   
27.
Interactions between taste receptors in the frog tongue   总被引:4,自引:0,他引:4  
Summary Receptors sensitive to stimulation with dilute CaCl2 solutions and located in different fungiform papillae of the frog tongue are cross-connected via branches of the glossopharyngeal nerve fibers to form chemical sensory units comprising on average about 3 papillae; often one or more papillae were found to be common to different units.The receptor response observed when single papillae were individually stimulated increased, when the strength of the stimulus was raised, at a much lower rate than that obtained by stimulating the whole tongue surface. This proves that the antidromic impulses travelling in the cross-connections linking different papillae result in an evident depression of the receptor response to CaCl2.The possible functional significance of mutual interaction between the receptors in the frog tongue is discussed.This study was supported by grants from the Consiglio Nazionale delle Ricerche (Impresa di Elettrofisiologia) of Rome, Italy.  相似文献   
28.
舌粘膜及粘膜下血管网的构筑及其临床意义   总被引:5,自引:0,他引:5  
本研究应用手术显微镜和扫描电镜观察了人舌粘膜的微血管构筑。舌深动脉长支和舌背动脉终支在舌粘膜下形成一完整的致密动脉网,跨越界沟和舌正中线,成为一整体。由动脉网发出微动脉支进入舌粘膜内,形成粘膜内的毛细血管网和各种乳头毛细血管丛。另外,还讨论了舌粘膜下馓血管构筑和舌瓣设计与临床舌诊的关系。  相似文献   
29.
 Glial cell line-derived neurotrophic factor (GDNF) has recently been shown to signal by binding to GDNF receptor-alpha (GDNFR-α), after which the GDNF-GDNFR-α associates with and activates the tyrosine kinase receptor Ret. We have localized Ret messenger RNA (mRNA) in the developing and adult rodent and compared with to the expression of GDNF and GDNFR-α mRNA. Ret mRNA is strongly expressed in dopamine neurons and α-motorneurons as well as in thalamus, ruber and occlumotor nuclei, the habenular complex, septum, cerebellum, and brain stem nuclei. Ret mRNA was also found in several sensory systems, in ganglia, and in nonneuronal tissues such as teeth and vibrissae. Very strong Ret mRNA signals are present in kidney and the gastrointestinal tract, where Ret and GDNF mRNA expression patterns are precisely complementary. The presence of Ret protein was confirmed in adult dopamine neurons using immunohistochemistry. GDNFR-α mRNA was strongly expressed in the developing and adult dopamine neurons. It was also found in neurons in deep layers of cortex cerebri, in hippocampus, septum, the dentate gyrus, tectum, and the developing spinal cord. In the kidney and the gastrointestinal tract, GDNFR-α mRNA and Ret mRNA distribution overlapped. Dorsal root ganglia, cranial ganglia, and developing peripheral nerves were also positive. GDNFR-α was additionally found in sensory areas and in developing teeth. Sensory areas included inner ear, eye, olfactory epithelium, and the vomeronasal organ, as well as developing tongue papillae. The temporospatial pattern of expression of GDNFR-α mRNA did not always match that of Ret mRNA. For instance, GDNFR-α mRNA was also found in the developing ventral striatum, including the olfactory tubercle, and in hippocampus. These areas seemed devoid of Ret mRNA, suggesting that GDNFR-α might also have functions unrelated to Ret. Received: 2 January 1997 / Accepted: 26 February 1997  相似文献   
30.
Perceptual Speed and IQ Are Associated Through Common Genetic Factors   总被引:1,自引:0,他引:1  
Individual differences in inspection time explain about 20% of IQ test variance. To determine whether the association between inspection time and IQ is mediated by common genes or by a common environmental factor, inspection time and IQ were assessed in an extended twin design. Data from 688 participants from 271 families were collected as part of a large ongoing project on the genetics of adult brain function and cognition. The sample consisted of a young adult cohort (mean age 26.2 years) and an older adult cohort (mean age 50.4 years). IQ was assessed with the Dutch version of the WAIS-3R. Inspection time was measured in the so-called -paradigm, in which a subject is asked to decide which leg of the -figure is longest at varying display times of the -figure. The number of correct inspections per second (i.e., the reciprocal of inspection time) was used to index perceptual speed. For Verbal IQ and Performance IQ, heritabilities were 85% and 69%, respectively. For perceptual speed, 46% of the total variance was explained by genetic variance. No differences in heritability estimates across age cohorts or sexes were found. Across the whole sample, a significant phenotypic correlation was found between perceptual speed and Verbal IQ (0.19) and between perceptual speed and Performance IQ (0.27). These correlations were entirely due to a common genetic factor that accounted for 10% of the genetic variance in verbal IQ and for 22% of the genetic variance in performance IQ. This factor is hypothesized to reflect the influence of genetic factors that determine axonal myelination in the central nervous system.  相似文献   
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