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91.
目的:对前庭导水管外口及内淋巴囊的解剖学位置进行显微解剖研究,探讨乙状窦前-迷路后入路中内淋巴囊保护的方法。方法:应用10例20侧10%福尔马林固定成人头颅标本,显微镜下模拟乙状窦前-迷路后入路手术方法解剖前庭导水管外口及内淋巴囊的位置并进行测量与比较。结果:前庭导水管外口在乳突腔面投影大致位于后半规管弧线前上3mm至其后下3mm的范围内。20例标本内淋巴囊的位置I型占60%(12例),II型占35%(7例),III型占5%(1例)。内淋巴囊尾端可越过乙状窦。磨除后半规管后下的骨质尽量保留3mm。外半规管延长线与乙状窦的交点、岩上窦向前暴露的最前端及乙状窦与岩上窦的交点组成三角形,循三角形的中心向顶点的连线做硬脑膜切口能够保护内淋巴囊的完整。结论:了解前庭导水管及内淋巴囊的具体位置并根据其位置设计切口利于保护内淋巴囊的结构完整和保护听力,利于术后关闭硬脑膜切口。  相似文献   
92.
AIMS: Diffuse haemangiomatosis of the spleen is a rare benign vascular condition occurring as a manifestation of systemic angiomatosis or, less commonly, confined to the spleen. It is sometimes accompanied by severe disturbance of blood coagulation. The goal of this study was to characterize an additional case of isolated diffuse haemangiomatosis of the spleen and to determine the histogenesis of this lesion which remains obscure. METHODS AND RESULTS: We describe a case of isolated diffuse haemangiomatosis of the spleen in which histological and immunohistological findings suggested the possibility of a malformative tumour-like lesion. The pathological cavernous vessels were distributed randomly through the red pulp, without continuity with sinuses. The endothelial cells expressed vimentin, factor VIII related antigen and CD34, but not CD8. Some cells lining the sinus lumen expressed CD68, lysozyme and myeloperoxidase. In addition, trabecular veins presented with intimal thickening. These results allow making a diagnosis between diffuse haemangiomatosis and other tumours/tumour-like lesions of the spleen, especially littoral cell angioma, splenoma and peliosis. CONCLUSION: If diffuse haemangiomatosis is usually classified as a benign proliferation of endothelial cells, we suggest that diffuse haemangiomatosis, when confined to the spleen, could be a tumour-like vascular lesion. In this hypothesis, the aetiology may be hamartomatous or malformative as is suspected in arterio-venous haemangioma of the lower extremities. The histogenesis is still questionable and no definitive proof in favour of one or the other hypothesis has been reported.  相似文献   
93.
Aims: We examined whether or not streptozotocin (STZ)‐induced diabetic rats, which have a lower heart rate (HR, beats min?1) than control rats, could maintain hypoxic ventilatory response. Methods: Twenty‐six Wistar rats, which had been injected with STZ (60 mg kg?1, EXP) or vehicle (0.1 m citrate buffer, CONT) intraperitoneally at 9 weeks of age, had their cardiorespiratory responses to normoxia and 12%O2 examined after 5 weeks. Results: Compared with CONT rats, EXP rats had a higher blood glucose [24 ± 3 vs. 5 ± 1 (mean ± SD) mmol L?1], a lower body weight (320 ± 23 vs. 432 ± 24 g), lower HR (303 ± 49 vs. 380 ± 44 in normoxia, and 343 ± 56 vs. 443 ± 60 in hypoxia) and a lower mean arterial blood pressure (MAP) (89 ± 6 vs. 102 ± 10 mmHg in hypoxia). In contrast, both groups had similar values in ventilation (), –metabolic rate (MR) ratio and arterial blood gases (ABGs). In EXP rats, with an acute insulin supplement (i.v., 0.75 U h?1 for 1.5–2 h), not only blood glucose, but also HR, and MAP were normalized as those obtained in CONT rats, and in hypoxia further increased without affecting –MR ratio and ABGs. Such acute cardiorespiratory stimulating effects of insulin could not be obtained in non‐diabetic rats (n = 7, 355 ± 24 g), in which euglycaemia (mean 6.4 mmol L?1) was maintained during the measurements. Conclusions: Our results suggest that, in STZ‐induced diabetic rats: (1) ventilation is hardly suppressed by hyperglycaemia, (2) cardiorespiratory responses can be acutely stimulated by short insulin injection, and (3) the effects, including those through acute blood glucose normalization, are possibly specific for the diabetic impairments.  相似文献   
94.
Summary Substance P (SP) is known to accelerate mucociliary (m.c.) activity in the rabbit maxillary sinus in vivo. The physiological significance of this finding was investigated by testing three putative SP antagonists. [Arg5, d-Trp7, 9, Nle11]SP5–11 could not be used as an antagonist because it stimulated m.c. activity. [d-Arg1, d-Trp7, 9, Leu11]SP had no effect on the m.c. activity changes induced by SP. [d-Pro2, d-Trp7, 9]SP was found to be an effective antagonist, 1 mg/kg of this drug reversibly inhibiting both the effects of 0.1 g/kg SP and the stimulating effect of 1.0 g/kg bradykinin and 30.0g/kg capsaicin; the stimulating effect of 0.5 g/kg methacholine was not inhibited. It is suggested that bradykinin and capsaicin stimulate m.c. activity at least partly by releasing SP.The results of this investigation also support the view that the accelerating effect of SP on m.c. activity reflects physiological SP-mediated protective mechanisms in the airways. It is concluded that [d-Pro2, d-Trp7, 9]SP is a useful pharmacological tool for studying the role of SP in the control of m.c. actvity in rabbits.  相似文献   
95.
Atrial pacing (AAI) in sick sinus syndrome (SSS) has been questionedbecause of the risk of distal conduction disturbances (DCD)and atrial tachyarrhythmias. The authors studied the incidenceof clinically relevant DCD and arrhythmias in 52 SSS patientswith AAI. The observation time was 25–67 (mean 48) months. Invasive electrophysiologic investigation was performed preoperativelyin 29 cases and preoperative atrial pacing to Wenckebach blockor to 150 ppm in 23. The preoperative investigation showed prolongedHV-time in three cases and Wenckebach block at 110ppm in onecase, while six patients had LAH-block, five RBB-block and twofirst degree A V-block. No further DCD developed in any of thesepatients. Second-degree type IA V-block developed in two patientsafter 2 and 19 months, respectively. One had been treated withdigitalis and verapamil and was asymptomatic. The other patient,who had a low ventricular rate, experienced near-syncope. Thesetwo blocks could not be predicted from the preoperative andperoperative investigations. In five patients (10%) permanent atrial fibrillation developedduring the follow-up period. The incidence of concomitant supraventriculartachyarrhythmias in the patients with the bradycardia-tachycardiasyndrome appeared to be unaffected by the pacemaker treatment.  相似文献   
96.
24 hour ambulatory electrocardiography was performed in a representativegroup of people born in 1897. Out of 73 people included in thestudy, 22 were without known heart disease, 15 had definiteischaemic heart disease (IHD) and 36 symptoms of possible cardiacorigin. An R-R interval in excess of 2000 ms was seen in only3 subjects and Wenckebach A-V block in only one. One subjectwithout a history of syncope had a nocturnal episode of completeA-V block with an escape interval of 8000 ms. The most strikingdifference between healthy subjects and patients with IHD wasthe higher number of patients with more than 1000 ventricularpremature beats (VPBs) per 24 hour and ventricular coupletscompared with the number of healthy subjects with such findings.At follow-up two years later 11% had died, with the highestmortality in patients with IHD (33%), and out of 8 patientswith IHD who had more than 1000 VPBs per 24 hour, 4 (50%) haddied compared with only one (14%) of those with less than 1000VPBs. Our results seem to indicate that more than 1000 VPBsper 24 hour is a very unusual finding in healthy 85 year oldindividuals. When it occurs in very old people, it is usuallyin connection with IHD, and in this setting it signifies a poorprognosis.  相似文献   
97.
目的评价起搏电极的植入途径及永久起搏器的类型.方法选择1987~1999年安置的80例永久起搏器患者.结果经颈外静脉植入电极6例,手术时间为256±75分;经头静脉植入电极48例,手术时间为247±65分(P>0.05);经锁骨下静脉途径植入电极26例,手术时间为118±35分(P均<0.01).其中,AAI型3例(4%),DDD型5例(6%),VVI型72例(90%).结论经锁骨下静脉植入起搏电极,方法简单,组织损伤小,手术时间短,优于其它途径.VVI型起搏器在我国仍然是主要使用的起搏器.  相似文献   
98.
功能性鼻窦内窥镜手术100例疗效观察   总被引:1,自引:0,他引:1  
目的:功能性鼻窦内窥镜手术的长期疗效。方法:采用Messerklinger术式为100例患者手术;并以传统术式治疗100例作对照。结果:内窥镜组临床治愈率81%,总有效率95%,明显优于传统手术组(P<0.05),手术并发症发生率为6%,明显低于传统组(P<0.05)。结论:内窥镜手术长期疗效可靠,并发症少,复发率低。  相似文献   
99.
为探讨临床上比较罕见的砂粒性骨化纤维瘤(psammomatoid ossifying fibroma,POF)的临床特征、诊断与治疗方法,分析了6例POF的临床资料并综合文献,提出POF是一种以青少年为主、具有局部侵袭性的良性肿瘤,有明确的组织形态特征,临床症状特别是CT扫描是临床诊断的基础,治疗原则是在彻底清除病灶的基础上,兼顾面容与功能的保护。  相似文献   
100.
傅斌  范姝  万军  包奇昌  周微红  黄勇 《中草药》2023,54(7):2182-2186
目的 探讨灵宝护心丹联合参松养心胶囊治疗窦性心动过缓的临床疗效。方法 选取2019年3月—2020年12月抚州市中医医院内科诊断为窦性心动过缓患者100例,随机分为对照组(50例)和治疗组(50例)。对照组给予参松养心胶囊(每天3次,每次4粒),治疗组在对照组的基础上给予灵宝护心丹(每天3次,每次4粒),治疗24周。治疗后比较两组的临床疗效、24 h动态心电图指标、心率变异性时域指标及不良反应。结果 治疗组中医证候有效率84.0%,对照组为60.0%,两组比较差异有统计学意义(P<0.05)。治疗组动态心电图总有效率86.0%,对照组64.0%,两组比较差异有统计学意义(P<0.05)。治疗后,两组平均心率、总心率、最快心率、最慢心率、24 h全部正常心室搏动间距(R wave-R wave,R-R)间期标准差(standard diviation of NN intervals,SDNN)、24 h连续5 min节段正常R-R间期的标准差(standard deviation of sequential five-minute R-R interval means,SDA...  相似文献   
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