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21.
“C”型曲线的中耳声学特性改变与鼓室积液的关系 总被引:10,自引:2,他引:8
对40耳声导抗检查为“C”型曲线患耳进行中耳系统共振频率点测试并进行鼓室穿刺抽液,结果表明:共振频率点低于600Hz,患耳鼓室积液阳性率为82.1%,高于600Hz患者鼓室和液阳性率16.7%,提示依据鼓室导抗图和共振频率点测定可初步判断“C”型曲线患耳鼓室积液的可能. 相似文献
22.
Alan G. Meehan Iain C. Medgett David F. Story 《Naunyn-Schmiedeberg's archives of pharmacology》1988,337(5):500-503
Summary The present study examined the involvement of Ca+ mobilization in the amplifying effect of serotonin on steady-state responses of rabbit isolated perfused ear artery to exogenous noradrenaline (NA; 0.001–3 ol/l). In contrast to its marked amplifying effect on responses to NA, serotonin in the subconstrictor concentration of 100 nmol/l had no effect on responses to KCl. The Ca+-entry blocking drug diltiazem (10 gmol/1) decreased responses to NA; in addition, the amplifying effect of serotonin on responses to NA was reduced by diltiazem. Lowering the concentration of Ca+ in the Krebs-Henseleit perfusion solution from 2.5 to 0.25 mmol/l also reduced both responses to NA and the amplifying effect of serotonin. Using the method of Manzini et al. (1982), separate intra- and extracellular Ca+-dependent responses to NA were obtained. Serotonin had no effect on intracellular Ca+-dependent responses to NA but enhanced extracellular Ca2+-dependent NA responses. These results suggest that the amplifying effect of serotonin on responses of rabbit ear artery to exogenous NA involves a selective enhancement of the component of the NA response which is dependent on extracellular Ca+; serotonin may increase NA-evoked entry of Ca2+ into the vascular smooth muscle cells through receptor-operated Ca+ channels.
Send offprint requests to A. G. Meehan at the above address 相似文献
23.
Sue Piper Duckles 《Neurobiology of aging》1983,4(2):151-156
The adrenergic control of vascular smooth muscle was compared in young and adult rabbits using a variety of in vitro techniques. Norepinephrine (NE) content and accumulation of 3H-NE were not different in blood vessels from the two age groups. In contrast, stimulation-evoked release of endogenous NE was reduced by 40–60% in vessels from the aged animals. Functional studies of smooth muscle contractions were carried out using isolated ring segments of the ear artery. There were no differences in the resting force-response relationship between vessels from young and adult rabbits. Maximum contractile responses to nerve stimulation, NE or KCl were not different in vessels from the two age groups, nor was the NE ED50. However, blockade of the neuronal uptake system with desmethylimipramine produced a greater shift in the NE concentration-response curve in vessels from the young animals compared to the shift in vessels from adult animals. This observation reflects a decline in neuronal NE uptake with age. Although maximal contractile responses to transmural nerve stimulation at 16 Hz were unchanged, responses to stimulation at lower frequencies were reduced in vessels from adult rabbits, an effect which was also enhanced when an antagonist of neuronal uptake was present. Thus, there is a decline in function of adrenergic nerves in adult animals, reflected in a decrease in stimulation-evoked NE release and a decrease in norepinephrine uptake revealed by functional studies. These two effects tend to balance each other, so that there is a small decrease in contractile response to adrenergic nerve stimulation which is exacerbated when neuronal uptake mechanisms are blocked. 相似文献
24.
Syun Hosoda Hiroo Tateno Hanae Kito Inoue Genzo Isojima Sadahiko Kondo Takayoshi Konishi 《Pathology international》1992,42(8):614-620
A 69-year old man complaining of longstanding hearing loss and mild otorrhea was found to have a mass obliterating the external auditory canal and polypous tympanic mucosa with accompanying absence of the tympanic membrane and ossicular chain. Tumors excised from the external auditory canal and tympanum showed histologic features essentially characteristic of a carcinoid tumor: a ribbon or festoon arrangement of tumor cells, formation of anastomosing cords and glandular spaces, presence of numerous argyrophilic as well as argentaffin secretory granules within many of the tumor cells, and ultrastructur-al evidence of neurosecretory granules in the tumor cell cytoplasm. Immunohistochemically, the tumor was found to contain not only neuronal marker substances such as neuron-specific enolase, S 100 protein and chromogranin A, but also serotonin and multiple peptide hormones such as pancreatic polypeptide, glucagon, cholecystokinin and leucine-enkephalin. A review of the pathology of 17 previous cases of carcinoid of the middle ear suggested that this type of carcinoid may have a variegated hormone profile among carcinoids of foregut origin, and hormonally may resemble ileal carcinoid arising from the midgut, although their histogenetic origins may differ, because of frequent production of serotonin. Acta Pathol Jpn 42: 614–620, 1992. 相似文献
25.
26.
目的探讨开放性乳突病变切除术后加速乳突术腔上皮化及缩小乳突术腔的有效办法。方法63例行开放性乳突病变切除术的患者按照复查治疗方法分为两组,异种脱细胞真皮组36例,应用异种脱细胞真皮基质覆盖术腔,碘仿纱条组27例,以碘仿纱条填塞术腔。术后随访两组患者,对比观察术腔愈合情况和上皮化时间。结果异种脱细胞真皮组术腔上皮化时间为2~4周,平均2.2周;碘仿纱条组术腔上皮化时间为9~35周,平均13.7周,异种脱细胞真皮组的上皮化时间短于碘仿纱条组(P〈0.01)。结论异种脱细胞真皮基质可促进上皮组织再生,减少术后感染及肉芽发生,加速乳突腔上皮化,提高开放性乳突病变切除术的疗效。 相似文献
27.
Masami Sakurai Nozomu Mori Ougi Horiuchi Nariaki Matsuura Yasushi Kobayashi 《Pathology international》1988,38(11):1453-1460
A primary tumor of the middle ear was examined histologically, histochemi-cally, immunohistochemically and ultrastructurally. Neuroendocrine cell differentiation, a carcinoid feature, was demonstrated by the presence of numerous argyrophil granules, as well as positive serotonin, glicentin, glucagon, and human pancreatic polypeptide (hPP) granules in some of the Grimelium-positive cells. Chromogranin A was also detected in the cells, but much less frequently than Grimelius-positive staining. Neither neuron-specific enolase (NSE) nor epithelial membrane antigen (EMA) was demonstrated in the tumor. Mucin was demonstrated only intraluminally. Electron microscopy revealed many typical neurosecretory granules in tumor cells, but no apical mucin granules. The tumor appeared to be benign, and there has been no sign of recurrence during a postoperative period of one year. ACTA PATHOL JPN38: 1453–1460, 1988. 相似文献
28.
分泌性中耳炎中耳积液和血清中sIL-2R水平的初步研究 总被引:2,自引:0,他引:2
应用酶联免疫吸附法(ELISA)对30例正常人血清(对照组)和60例分泌性中耳炎患者(SOM组)中耳积液和血清中可溶性白细胞介素2受体(sIL-2R)进行了检测。结果示SOM组血清sIL-2R水平明显高于对照组,MEF中其含量明显高于血清;鼻咽癌组血清及MEF中sIL-2R水平明显高于─般SOM组;粘液组高浆液组;慢性组高于急性组(均P<0.01)。提示:血清及MEF中sIL-2R水平的测定有助于对SOM患者免疫状态的评估;MEF中sIL-2R可能主要由局部中耳粘膜产生;MEP中高浓度的sIL-2R存在可能是SOM迁延不愈的─个原因。 相似文献
29.
The topical anti-inflammatory properties of flutrimazole, a new imidazole antifungal, have been evaluated. Flutrimazole inhibited mouse ear oedema induced by arachidonic acid, tetradecanoylphorbolacetate and dithranol, with IC50 values of 3.32, 0.55 and 2.42 mols/ear, respectively. Ketoconazole showed similar potency in arachidonic acid and dithranol models (IC50=3.76 and 2.41 mols/ear) whereas it was less active against tetradecanoylphorbol acetate (IC50=1.96 mols/ear). The standard anti-inflammatory sodium diclofenac was overall slightly more potent than antifungals (IC50=2.23, 0.57 and 0.57 mols/ear against arachidonic acid, tetradecanoylphorbol acetate and dithranol, respectively). Both 2% flutrimazole and 2% ketoconazole creams, applied topically, inhibited carrageenan-induced rat paw oedema by about 40%. Under the same conditions, 1% flutrimazole and diclofenac creams inhibited by 26 and 54%, respectively. Flutrimazole may work through the inhibition of 5-lipoxygenase, as it inhibited LTB4 production by human granulocytes with an IC50 value of 11 M (IC50 value for ketoconazole was 17 M), whereas ram seminal vesicle cyclooxygenase was only inhibited by 16% at a concentration of 25 M. Drugs such as flutrimazole, with dual anti-inflammatory/antifungal activity, may be advantageous in the treatment of topical fungal infections with an inflammatory component.accepted by I. Ahnfelt-Rønne 相似文献
30.
中耳占位性病变的CT诊断 总被引:1,自引:0,他引:1
目的:探讨中耳不同占位性病变的CT诊断及鉴别诊断问题。方法:对手术病理证实的25例中耳良性及恶性占位性病变患者的CT图像资料进行分析,分别总结其CT诊断及鉴别诊断要点。结果:(1)胆脂瘤:肿物多为单发,中心多位于上鼓室或鼓窦入口区,常破坏鼓室盾板,骨破坏区边缘多清晰硬化,常见听小骨受压移位表现。(2)炎性肉芽肿:肿物呈多发结节状或斑片状,病灶常相连并紧贴鼓室或鼓窦壁附壁分布伴边缘清楚的骨破坏。(3)中耳癌:肿物及骨破坏区形态极不规则,边缘模糊不清,可累及中耳结构以外的骨结构;骨破坏区达乳突或岩骨边缘者,CT横断层面示乳突或岩骨边缘骨壁呈“多点中断”表现。结论:听小骨移位及鼓室盾板骨破坏为诊断胆脂瘤最可靠和重要的依据;骨破坏区边缘模糊,乳突或岩骨边缘骨壁呈“多点中断”表现为中耳癌的特征性CT征象。 相似文献