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排序方式: 共有4936条查询结果,搜索用时 15 毫秒
61.
目的 探讨肝段下腔静脉阻塞症的有效治疗方法。方法 54例病人中,20例下腔静脉隔膜破膜术,5例行下腔静脉切开根治性隔膜切除术,16例行下腔静脉右心耳人造血管转流术,8例行肠系膜上静脉-右心耳人造血管转流术;4例作了下腔静脉-右心耳、肠系膜上静脉、下腔静脉人造血管联合转流术,1例行肺包脾手术。结果 本组54例患者中,除3例分别于术后12d、45d、7个月因肝肾功能衰竭死亡死亡外,其余51例术后症状明 相似文献
62.
目的:探讨内科急危重患为进行静脉营养,休克救治及中心静脉压监测,肿瘤的系统化疗,建立静脉通路最人选择与术后护理。方法:42例中选择锁骨下静脉置管术11例,选择腋静脉末端置管术31例。结果:术后经X检查,导管前端到达上腔静脉39例,到位率为92.8%,到达颈内静脉3例(占7.14%),无气胸、血胸、空气栓塞等并发症。结论:内科危重症患及肺心病、肺癌、脓胸、扩张型心肌病建立静脉通道可选用腋静脉末端 相似文献
63.
目的评价B超对肺癌急症的快速鉴别诊断价值。方法应用B超诊断肺癌急症35例,其中有中央型右上肺癌肿块压迫引起的上腔静脉综合征(SVC)5例,探查取胸骨右缘第2、3肋间;中大量心包积液伴亚急性心包填塞症10例,包括心肌与心包转移癌致急性出血性心包积液2例,探查取心前区及左腋前线第5、6肋间;恶性胸腔大量积液20例,探查位于两侧背部膈上。介入性治疗,B超定位穿刺抽液并腔内注入中药榄香烯乳,配合临床化疗药物、输血等综合治疗。结果在4周内急症得到暂时缓解者占82.8%,稳定占8.5%,无效占8.5%。结论简便、可重复性的超声诊断及时、可靠,并可提供疗效参考依据,证实榄香烯乳对控制急性心肌心包出血有特效,起乳剂微栓止血作用。对部分包裹性胸腔积液无效。B超对SVC诊断有一定局限性。 相似文献
64.
目的 研究次声对下丘的作用机制。方法 用抗 F O S 蛋白和抗神经型一氧化氮合成酶(nc N O S) 免疫组织化学方法,将大鼠暴露于8 Hz 、120 d B 的次声中,持续2 小时,观察下丘 F O S 蛋白的表达情况及其与nc N O S 阳性神经元的关系。结果 在下丘出现大量 F O S 样及散在的nc N O S 样免疫反应阳性神经元,且部分nc N O S阳性神经元的胞核同时呈 F O S 染色阳性,这种 F O S/nc N O S 双标记神经元约占 F O S 阳性神经元总数的10 % 。结论 部分nc N O S 神经元参与对次声刺激的反应。 相似文献
65.
Colour Doppler ultrasound assessment of the inferior vena cava in patients with Wilms' tumour 总被引:2,自引:0,他引:2
OBJECTIVE: To assess the diagnostic accuracy of colour flow Doppler ultrasound in diagnosing inferior vena caval (IVC) extension of tumour thrombus in patients with Wilms' tumour. MATERIALS AND METHODS: Over a 3-year period from June 1994 to June 1997, 74 patients with Wilms' tumour were referred to our institution. In this retrospective study we reviewed the preoperative colour flow Doppler ultrasound reports of 64 of these patients and compared the reports with the intra-operative findings in 51 patients who underwent surgery. RESULTS: Vena caval extension of tumour thrombus was present in 12 patients (18.7%) and in six of these patients (9.4%) there was also atrial extension of the tumour. Colour flow Doppler ultrasound correctly diagnosed IVC extension of tumour thrombus in nine patients and correctly predicted the cranial extent of the tumour thrombus in eight patients. CONCLUSION: Colour flow Doppler ultrasound has an overall positive predictive value of 73.4% in assessing IVC patency and correctly diagnosing IVC extension of tumour thrombus, in patients with Wilms' tumour. However, non-diagnostic ultrasound examinations can occur in over 20% of patients. 相似文献
66.
Background: Colic ischemia is a serious complication that can occur after abdominal aortic surgery. It has been described in two patients
after laparoscopic aortic surgery. The goal of the current experiment was to determine the feasibility of inferior mesenteric
artery (IMA) reimplantation during laparoscopic aortobifemoral bypass (LAFB).
Methods: Six piglets were submitted to the laparoscopic approach according to the ``apron' technique previously described. The infrarenal
aorta was clamped and an LAFB was performed using a dacron graft. The IMA was reimplanted in the body of the graft with a
running 5-0 polypropylene suture.
Results: Mean operation and dissection times were 282.5 min (range, 270–310 min) and 123 min (range, 110–140 min), respectively, with
a mean blood loss of 108 ml (range, 80–150 ml). Aortic clamping and anastomotic times were 123 min (range, 110–135 min) and
33 min (range, 24–45 min), respectively. The IMA reimplantation took 55 min (range, 45–70 min). At autopsy, all anastomoses
were patent with no stenosis nor leak.
Conclusion: Laparoscopic IMA reimplantation during laparoscopic aortobifemoral bypass is feasible.
Received: 10 July 1998/Accepted: 15 November 1998 相似文献
67.
Donatella Carretta Anne Herv-Minvielle Victoria M. Bajo Alessandro E. P. Villa Eric M. Rouiller 《Brain research》1999,841(1-2):170-183
Neuronal activity was established in the auditory pathways in relation to behavioural response and cognitive information processing during a sensory-motor acoustic learning. Rats were trained in three consecutive phases. The first phase was an association between an auditory stimulus and a food reward; the second phase a simple discrimination between two sounds of different frequency components, and the third phase a more complex discrimination involving both spectral and spatial sound dimensions. Auditory stimuli were bursts of complex sounds lasting 500 ms. Neuronal activity related to the behaviourally relevant stimuli was established in 20 "learning" rats undergoing this protocol, which were progressively sacrificed at the beginning, middle and end of each phase. For comparison, activity was also established in four "control" rats exposed to the same stimuli delivered pseudo-randomly, thus carrying no behavioural meaning. Neuronal activity was assessed immunocytochemically using the functional marker Fos. To establish a baseline, two rats were unexposed to controlled acoustic stimulation ("unstimulated" rats). In the superior olivary complex (SOC), inferior colliculus (IC) and medial geniculate body (MGB), the number of Fos-like immunopositive cells was comparable in "learning" and "control" animals, but higher than in the "unstimulated" rats. In the auditory cortex (AC), most prominently in the secondary area Te2, the number of Fos-like positive cells differed between "learning" and "control" rats, suggesting that the auditory cortical areas may be involved in the encoding of the behavioural significance of the acoustic stimuli. 相似文献
68.
The inferior colliculus is involved in conveying auditory information of an aversive nature to higher cortical structures.
Gradual increases in the electrical stimulation of this structure produce progressive aversive responses from vigilance, through
freezing, until escape. Recently, we have shown that microinjections of NMDA into the inferior colliculus mimic these aversive
effects and that the neural substrates responsible for learned escape behavior in the inferior colliculus are regulated by
GABA−benzodiazepine mechanisms. In the present study, we extend these observations showing that unlearned aversive responses
are also depressed by muscimol and midazolam, both GABA-benzodiazepine agonists, and that microinjection of glutamate, an
excitatory amino acid, into the inferior colliculus can trigger freezing responses. Electrical stimulation of the inferior
colliculus of rats placed inside an open field allowed the determination of thresholds for the aversive responses, alertness,
freezing and escape. Systemic administration (3 and 5.6 mg/kg) as well as microinjections into the inferior colliculus of
the anxiolytic compound midazolam (10, 20 and 40 nmol) caused increases in threshold for these aversive responses. Similar
results were obtained following microinjections of the GABA-A agonist muscimol (0.1, 1 and 5 nmol) into this brainstem structure.
Microinjections of low doses of glutamate (5 nmol), presumed to activate mainly AMPA/kainate receptors, into the ventrolateral
division of the central nucleus of the inferior colliculus of rats placed inside a circular arena induced aversive reactions,
characterized by freezing responses. However, higher doses of glutamate caused no apparent effects. GDEE, an AMPA/kainate
receptor antagonist, inhibited, whereas AP7, a NMDA receptor antagonist, did not influence these responses. It is suggested
that GABA-benzodiazepine processes modulate the expression of defensive reactions in the inferior colliculus and that activation
of fast-acting excitatory amino acid receptors in this midbrain region can trigger the initial steps of the defense reaction
without eliciting the motor explosive behavior usually seen following the activation of NMDA receptors.
Received: 13 May 1998 / Final version: 12 August 1998 相似文献
69.
鼻腔神经部分切断术及下鼻甲粘骨膜下剥离术治疗变应性鼻炎18例临床分析 总被引:4,自引:2,他引:4
目的:观察鼻腔神经部分切断术和下鼻甲粘骨膜下血管神经离断术对变应性鼻炎的疗效。方法:对18例常年性变应性鼻炎患者进行鼻腔神经部分切断术与下鼻甲粘骨膜下血管神经离断术。所有病例随访12个月,评价其临床效果。结果:10例临床症状消失,体征明显改善;7例临床症状明显缓解,体征改善;1例无效。总有效率94.4%。结论:鼻腔神经部分切断和下鼻甲粘骨膜下血管神经离断术治疗常年性变应性鼻炎效果显著。 相似文献
70.
目的 探讨并总结包括腔静脉旁部肝尾叶切除的方法和经验。方法 分别采用右后途径和左侧途径行右尾叶和全尾叶切除;前者附加部分右后叶切除,后者可为单独全尾叶切除或附加左外叶或左半肝切除。结果 成功施行包括腔静脉旁部的肝尾叶切除13例,其中右尾叶切除7例,全尾叶切除6例;全组无手术死亡,术中、术后均无严重病发症发生;术后平均失血量为896.15ml,平均肝门阻断时间为25.40min,术后平均住院12.38天。结论 虽然解剖关系复杂,切除包括腔静脉旁部的肝尾叶安全可行。 相似文献