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141.
大鼠腹主动脉注入1%墨汁硝酸银溶液,可同时显示小肠淋巴管和微血管,浆膜下注入10%ABS丁酮溶液可制成小肠粘膜淋巴管的铸型标本,用光镜和SEM观察,利用图像分析仪测量了肠粘膜淋巴管的数量、管径、长度等。小肠粘膜初始淋巴管数为275±52/mm2,管径为349±40μm,长度为2085μm,初始后淋巴管管径为349+40μm,长度1074μm,提出了区分初始淋巴管和初始后淋巴管的依据,获得了有关汇合淋巴管、粘膜下层淋巴管网数、园形因子等数据,小肠不同区段如十二指肠、空肠、回肠、淋巴管的上述数据有某些差别。我们的研究结果加深了对大鼠小肠淋巴管的分布、走行和形态等的认识 相似文献
142.
不同月龄正常大鼠骨形态计量学参数动态变化的研究 总被引:3,自引:0,他引:3
目的 :探讨不同月龄正常大鼠骨形态计量学参数变化 ,为抗骨质疏松药物研究提供对照依据。方法 :4 .5月龄SD雌性大鼠 ,按体重随机分组 ,在实验的d 0 (4.5月龄 )、d 30 (5 .5月龄 )、d 75 (7月龄 )、d 14 0 (10月龄 )杀死大鼠取材 ,采用体内双荧光标记法 ,胫骨上段硬组织包埋切片及松质骨形态计量学分析 ,观察不同月龄段大鼠的骨变化情况。结果 :正常大鼠 4 .5~ 10月龄 ,骨量有一缓慢上升后下降的过程 ,但变化辐度不大 (P >0 .0 5 ) ,骨量相对稳定 ,骨形成和骨吸收有先上升后下降的变化过程 (P <0 .0 5 )。结论 :4 .5~ 10月龄的SD雌性大鼠体重和骨计量学参数变化正常 ,选择该月龄段大鼠做模型 ,研究药物对骨质疏松的防治是可行的。 相似文献
143.
The ventrolateral periaqueductal gray (PAG) and pontine reticular formation (PRF) are implicated in the neuronal network for audiogenic seizures (AGS). The AGS of genetically epilepsy-prone rats (GEPR-9s) culminate in tonic hindlimb extension (TE), and elevated acoustically evoked neuronal firing and burst firing, immediately preceding TE, have been observed in PAG and PRF. This study examined changes in PAG and PRF neuronal firing and behavior in GEPR-9s, following phenytoin administration. Recordings involved 16 PAG and nine PRF neurons in GEPR-9s. Phenytoin in doses (mean, 6. 3 mg/kg) that suppressed TE selectively did not consistently alter PAG neuronal firing. However, these doses of phenytoin resulted in significant (51.6% of control) suppression of PRF neuronal firing. Doses of phenytoin (mean, 8.3 mg/kg), which completely blocked AGS, significantly reduced PAG neuronal firing (64.6% of control), and more greatly suppressed PRF firing (25.8% of control). These results are consistent with a critical role for PRF neurons in generation of TE not evident for PAG. The suppression of PAG and PRF neuronal firing induced by phenytoin with complete seizure blockade is consistent with vital roles for both structures in the seizure network. The differential effects of phenytoin on structures requisite to the seizure network indicate that this experimental approach may be able to identify the most sensitive therapeutic target for anticonvulsant drugs, which could be critical to pharmacological suppression of specific seizure behaviors manifest in various types of convulsions, potentially including human epilepsy. 相似文献
144.
The ventral hippocampal formation (vHF) seems to constrain diverse responses to psychological stimuli, and disruption of this function may underlie severe neuropsychiatric diseases. In particular, the ventral subiculum inhibits hypothalamic-pituitary-adrenal axis (HPA) activity following psychological, but not systemic, stressors. Despite the difficulty in interpreting such HPA responses, they have been relied upon to further characterize vHF function, because increased HPA axis activity is implicated in neuropsychiatric disturbances, and reliance on behavioral and cognitive data is even more problematic. Plasma arginine vasopressin (pAVP), which is inhibited by psychological stimuli and is also implicated in diverse neuropsychiatric diseases, provides a less ambiguous measure of CNS function. To test if its inhibition by psychological stress is also mediated by the vHF, we conducted two studies. In the first, pAVP and behavioral responses to novel acoustic stress were assessed in rats with bilateral excitotoxic lesions of the ventral subiculum and the ventral hippocampus. The subiculum lesions blocked the fall in pAVP and enhanced escape behaviors, whereas the hippocampal lesions produced responses intermediate to those in the subiculum-lesioned and control rats. In the second study, the pAVP response was similarly blocked by small lesions restricted to those vHF subfields which project to the neuroendocrine hypothalamus, compared to the response in animals with lesions in other vHF subfields. These results indicate that discrete projections from the vHF inhibit the pAVP response to psychological stimuli, and suggest that pAVP may provide a reliable probe of vHF activity. 相似文献
145.
Haberthür C Elsasser S Eberhard L Stocker R Guttmann J 《Acta anaesthesiologica Scandinavica》2000,44(6):749-757
BACKGROUND: In tracheally intubated or tracheostomized spontaneously breathing patients, tube resistance can highly increase the patient's work of breathing. In this study we focused upon the relationship between total (WOBtot) and tube-related additional inspiratory work of breathing (WOBadd) and compared different ventilatory modalities for proper tube compensation. METHODS: In ten tracheostomized spontaneously breathing patients we measured WOBtot and WOBadd in the continuous positive airway pressure (CPAP) mode, under inspiratory pressure support of 5, 10, and 15 cmH2O in the pressure support ventilation (PSV) mode, and under flow-adjusted pressure support in the automatic tube compensation (ATC) mode. WOBadd and WOBtot were calculated on the basis of measured tracheal pressure and esophageal pressure, respectively. Inspiratory peak tracheal pressure above PEEP was taken as an estimate of pressure support beyond mere tube compensation (i.e., overcompensation). RESULTS: The percentage of the tube-related WOBadd on WOBtot in the CPAP mode was 52%. It decreased with increasing pressure support in the PSV mode from 32% (PSV 5 cmH2O) to 17% (PSV 15 cmH2O). WOBadd was only 15% of WOBtot in the ATC mode. In contrast to the other ventilatory modes, reduction of WOBadd in the ATC mode was achieved with the smallest amount of overcompensation, i.e. with minimal pressure assist beyond mere tube compensation. CONCLUSION: In tracheally intubated or tracheostomized spontaneously breathing patients, adequate compensation of tube resistance (i.e. with minimal overcompensation and minimal undercompensation) is best done by the ATC mode. 相似文献
146.
慢性化脓性中耳炎的咽鼓管功能对手术疗效的影响 总被引:3,自引:0,他引:3
目的探讨慢性化脓性中耳炎咽鼓管功能改变对手术疗效的影响.方法分析40耳行鼓室成形术的慢性化脓性中耳炎的咽鼓管功能与手术疗效的关系.咽鼓管功能检查用正-负压试验、TTAG法及音响法,咽鼓管鼓室口及咽口的观察分别用鼓室镜及鼻窦镜,对比分析咽鼓管功能改变与病变部位的关系,并比较鼓室成形术后咽鼓管功能正常耳与异常耳的鼓膜生长及听力变化情况.结果慢性化脓性中耳炎的咽鼓管功能与鼓室口病变程度相关,鼓室口病变轻者,咽鼓管功能良好;而鼓室口病变重者咽鼓管功能不良.40耳鼓室成形术后咽鼓管功能良好耳鼓膜生长良好,咽鼓管功能不良耳鼓膜生长欠佳;两者均有统计学意义.结论慢性化脓性中耳炎咽鼓管功能与鼓室成形术效果关系密切,咽鼓管功能障碍可能是导致手术失败的重要因素之一. 相似文献
147.
乳头溢液514例分析 总被引:2,自引:0,他引:2
目的 :探讨乳头溢液的病因和诊断方法 ,有效降低乳腺疾病的发生。方法 :采用乳头溢液涂片检查对 5 14例乳头溢液病例进行回顾性分析。结果 :乳腺导管内乳头状瘤 31.13% ,乳腺囊性小叶增生 2 2 .5 7% ,乳腺癌 14 .78% ,导管扩张症 13.0 4 % ,乳腺炎 12 .4 5 % ,其他 6 .0 3%。结论 :乳头溢液脱落细胞学检查是乳头溢液病因及诊断的首选检查 ,近红外线扫描检查有助于诊断。半数以上≥ 5 0岁乳头溢血患者是乳腺癌患者。早诊、早治溢液性乳腺疾病是防止乳腺癌的重要措施。 相似文献
148.
目的 探讨高频电灼联合硅胶管植入术治疗泪小(总)管阻寨的适应证,手术方法和临床疗效.方法 对2年来行高频电灼联合硅胶管植入术治疗的泪道阻塞62例(68只眼),进行回顾性分析.结果 62例(68只眼)泪小(总)管阻塞有效率达88.2%.结论 高频电灼联合硅胶管植入术治疗泪小(总)管阻塞具有成功率高,操作简便,并发症少,经济,损伤小和美观等优点,具有临床适用价值. 相似文献
149.
309例神经管缺陷围产儿相关因素研究 总被引:1,自引:1,他引:1
目的:描述1998~2003年期间辽宁省围产儿神经管缺陷(NTDs)的特征及变化趋势。方法:以医院为基础的监测方法。结果:辽宁省累计NTDs发生率9.99/万,其中男性6.95/万,女性13.15/万,城市5.96/万,农村17.35/万。无脑畸形发生率6年下降73.19%。母龄别发生率为25~29岁组发生率最低;孕妇末次月经在8、9月时出生的男性NTDs高发。NTDs围产儿早产占51.78%,低出生体重占46.92%,围产期病死率为75.08%。结论:辽宁省围产儿NTDs发生率女性高于男性,农村高于城市。男性NTDs发生有季节性流行趋势。NTDs儿围产期病死率高,预后差。加强药物预防、科普宣教和产前诊断是降低其发生率的有效措施。 相似文献
150.
Surinder K. Singhal Ramandeep S. Virk Arjun Dass Bimaljit Singh Sandhu 《Indian journal of otolaryngology and head and neck surgery》2006,58(3):300-302
Tracheoesophageal fistula is a life threatening condition. Patients not managed surgically ultimately die of their disease.
Surgical management is the treatment of choice. We present a case of a patient that developed a tracheoesophageal fistula
after tracheostomy. Surgical repair was done which failed due to infection. The patient was managed with the help of an esophageal
stent and Trichloroacetic Acid cautery. This approach can be used in selected patients, depending upon the size and site of
TEE Larger fistulae and those situated lower down e.g. supra carinal cannot be managed by this technique. 相似文献