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1.
Yuan Peng Yuman Li Haiyan Cao Liu Hong Yu Wang Mingxing Xie 《Journal of ultrasound in medicine》2019,38(2):539-544
A pulmonary artery (PA) sling is a very rare congenital cardiovascular anomaly, and only a few studies have reported PA slings in fetuses. The relationship of the PA, aorta, ductus arteriosus, and trachea can be evaluated in the 3‐vessel and 3‐vessel and trachea views during fetal echocardiography. A PA sling can be detected by abnormal positioning of the left PA in relation to the trachea when sweeping from the 3‐vessel view cranially to the 3‐vessel and trachea view. Here we report 3 cases of fetal PA slings and their follow‐ups. Two cases were confirmed by postnatal echocardiography, and the other case was confirmed by a cardiovascular cast after pregnancy termination. We emphasize that the 3‐vessel and 3‐vessel and trachea views are of crucial importance in the prenatal diagnosis of a PA sling. 相似文献
2.
Granular cell tumours rarely involve the lower respiratory tract. We report eight cases surgically resected at our institution. There were four females and four males, aged between 18 to 56 years (mean 40). One tumour associated with a peripheral lung adenocarcinoma was asymptomatic. The other lesions presented with obstructive pneumonitis (3 cases), haemoptysis (2), dyspnea (1) or cough (1). These tumours were tracheal (1) or bronchial (6) and one case was located in the lung parenchyma. Four cases were multicentric with associated lesions located in a bronchus (2), the oesophagus (1) or a mediastinal lymph node (1). All tumours, with the largest diameter ranging from 0.5–4.5 cm, were histologically invasive. The tumours were positive for S-100 protein, neuron specific enolase, KP1 (CD68) and vimentin. No tumour expressed desmin, keratin or p53 oncoprotein. Our study demonstrates that, in spite of marked anatomical and clinical polymorphism, the rare granular cell tumours of the lower respiratory tract have a constant histological appearance. Our observations confirm that large tumours (> 8–10 mm) usually extend beyond the tracheo-bronchial cartilages and, therefore, only surgical treatment may avoid recurrence. 相似文献
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Necrotizing sialometaplasia is a benign condition first described in minor salivary glands of the soft palate with morphological changes which can be misinterpreted as squamous-cell carcinoma. Similar lesions have been subsequently reported in other locations including major salivary glands, lip, breast and skin (the term syringometaplasia has been applied for the latter). We report three cases of such a process involving submucosal glands in the trachea following prolonged translaryngeal intubation. 相似文献
5.
院前紧急气管插管与机械通气24例临床分析 总被引:1,自引:0,他引:1
目的总结紧急气管插管与机械通气在院前急救中应用的经验,以期提高院前急救水平。方法回顾性分析24例院前气管插管与机械通气抢救心搏呼吸骤停病人的临床资料。结果24例病人气管内插管均获成功,成功率100%。完成气管内插管的时间是15s~60s,平均时间(25±15)s。心搏、自主呼吸恢复4例(16.7%),心搏恢复8例(33.3%);心搏及自主呼吸均未恢复12例(50.0%)。结论气管插管与机械通气是急诊抢救危重病人的基础,对保证进一步心肺复苏、挽留手术机会以及提高危重患者抢救成功率有重要意义。要加强对抢救人员进行紧急气管插管和机械通气的培训。 相似文献
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淫羊藿总黄酮对肾上腺素β_1受体的特异性阻断作用 总被引:2,自引:0,他引:2
为探讨淫羊藿总黄酮(TFE)对肾上腺素受体的作用,本实验用离体兔心房肌、主动脉及豚鼠气管观察了TFE对肾上腺素全体的作用,结果TFE(0.13g/L)抑制心房肌肌力和频率,并使异丙肾上腺素(ISO)对心房肌正性频率作用的量效曲线平行右移,但无钙拮抗作用及M受体激动效应,且不影响ISO对豚鼠气管条的负性肌力作用及去甲肾上腺囊(NE)对兔主动脉条的收缩作用。提示TFE选择性阻断肾上腺素β_1受体。 相似文献
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Artificialtrachealprosthesisisnowachallengetotheentiresurgicalfieldallovertheworld Previously ,allkindsofprosthesiswere“innerstent”thatcouldnotbeintegratedwithnativetrachea Sincethereisaninterfacebetweensmoothsurfaceofthe prosthesisandlivingtissues,andtheinnersideoftheprosthesisisnotcoveredwithlivingmembrane,infectionsalwayshappenaroundtheprosthesis Wethendevelopedanewtechnique,whichcombinedmemory alloymeshwithtraditionaloperativeprocedures Memory alloymeshisextensible,flexibleandcanmaintain… 相似文献
10.
Substance P is one of the peptides released from sensory nerves that mediate "neurogenic inflammation." Although substance P-immunoreactive (SP-IR) axons are known to be present within the mucosa of the respiratory tract, the relative extent of the innervation of various components of the mucosa is not known. Therefore, we determined the distribution and number of SP-IR axons in the rat trachea and bronchi, by using immunohistochemistry on tissue whole mounts. Specifically, we sought to learn whether these axons directly innervate the postcapillary venules involved in neurogenic plasma extravasation, the arterioles involved in neurogenic vasodilatation, and the airway smooth muscle involved in bronchoconstriction in pathogen-free, adult male F344 rats. We found that 90% of the SP-IR axons were single axons, usually having varicosities. Eighty-five percent of these were in the epithelium, 6% innervated arterioles, and the remainder elsewhere in the lamina propria. Only 10% of the mediator-sensitive postcapillary venules (i.e., venules labeled with Monastral blue pigment after challenge with capsaicin or substance P) were within 10 microns of SP-IR axons. SP-IR axons were more than 10 times as frequent in the smooth muscle of the distal bronchi as in the trachea. Capsaicin pretreatment (168 mg/kg over 7 days) reduced the number of SP-IR axons in the trachea by 96%, which is consistent with their being sensory. Unilateral vagotomy reduced the number of SP-IR axons bilaterally in the trachea and ipsilaterally in the main stem bronchus. Using an antibody to Protein Gene Product 9.5 as a nonspecific marker for all nerves in the trachea, we determined that SP-IR axons constituted 90% of the axons in the epithelium, 32% of the axons on arterioles, and only 4% of the axons in the smooth muscle. We conclude that most SP-IR nerves in the trachea are sensory axons and most of these axons end in the epithelium. SP-IR axons innervate mucosal arterioles, but few innervate postcapillary venules. Therefore, the mechanism by which sensory axons evoke plasma extravasation from these venules is likely to involve the diffusion of the peptide or a secondary mediator from the epithelium or from the arterioles upstream. 相似文献