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81.
Sutureless bowel anastomosis using Nd:YAG laser   总被引:5,自引:0,他引:5  
Small bowel anastomoses were performed without sutures by using the Nd:YAG laser to produce welded enterotomies. Optimal energy levels for contact and noncontact laser were determined. Anastomoses produced using five target energy levels between 100 and 500 J were examined. Short-term anastomotic strength of these enterotomies was measured 1 min after the welding. Bursting pressure of the laser welded enterotomies was compared to the bursting pressure of traditional two-layer, inverting, interrupted sutured bowel anastomoses. The overall mean bursting pressure of non-contact-welded enterotomies was 50.6 mmHg. Optimal laser settings determined in this initial phase were then used to produce anastomoses in rabbits which are recovered postoperatively for 1 or 2 weeks in order to examine long-term viability and integrity of the anastomoses. All chronic rabbit preparations recovered without complication. The mean bursting pressure was 200 mmHg, not significantly different from that of uncut bowel or two-layer sutured anastomosis.  相似文献   
82.
Treatment of frog neuromuscular preparations with chlorpromazine (5 mumol/l) resulted in a marked rise in miniature endplate potential (MEPP) frequency of greater than 100% within 30 min, and an increase in evoked transmitter release (quantal content 5-15) of about 35%. Treatment with chlorpromazine sulphoxide (5 microM), a derivative of chlorpromazine with a much lower affinity for calmodulin, had very little effect on either form of transmitter release. It is concluded that stimulatory effects of calmodulin-binding drugs at the nerve terminal may well be exerted through calmodulin inhibition. The stimulatory effect of chlorpromazine on MEPP frequency was markedly reduced in preparations bathed in EGTA-containing Ca2+-free saline, but the response was largely restored by raising the temperature by 3-4 degrees C. It is argued that despite this partial dependence on [Ca2+]o, stimulation of transmitter secretion by chlorpromazine is likely to be mediated by inhibition of calmodulin-activated Ca2+-ATPases, and consequent elevation of [Ca2+]i.  相似文献   
83.
In vivo electrochemical methods were employed to study the potassium (K+-evoked release of monoamines from the cerebellum of the chloral hydrate anesthetized rat. K+-evoked releases were elicited using micropipette-Nafion-coated graphite epoxy electrode arrays in the granule/Purkenje cell layer, molecular layer, and white matter. These recorded releases were generally found to be reversible, moderately dose-dependent, and reproducible. However, the temporal dynamics of the releases were different for the cell layer versus molecular layer records. Releases were infrequently observed in cerebellar white matter, an area which is relatively devoid of monoamine containing terminals. The signals recorded from the cell and molecular layers were significantly attenuated by pretreatment with nomifensine, a potent catecholamine reuptake blocker, significantly prolonged the K+-evoked signals observed in both the granule/Purkenje cell and molecular layers. These data, taken together with earlier reports on the electrophysiological responses to activation of cerebellar noradrenergic inputs, support the conjecture that in vivo electrochemical recording methods have the sensitivity and spatial resolution for studies of functional monoamine release from brain regions that have a diffuse or laminated monoamine innervation.  相似文献   
84.
Heparin-induced Extracorporeal LDL-Precipitation (HELP) is an effective procedure for the elimination of both plasma LDL and fibrinogen. In 10 adult patients with severe type II hyperlipoproteinemia, a single HELP treatment of 3 1 plasma led to an acute decrease in the average plasma viscosity (PV) from 1.30 to 1.1 mPas. At the same time, an even more marked decrease in the mean erythrocyte aggregation rate from a pathological value of 7.9% to a value of 3.7% (normal range less than 5%) was observed. Long-term studies on five patients demonstrated a lasting improvement in these two haemorheological variables. The acute rheological changes were also accompanied by an improvement in polarographically determined muscle oxygen tension. Mean oxygen tension values measured in both the m.biceps brachii and the m.tibialis anterior in five patients before and after a single HELP treatment increased from 30 +/- 4 to 37 +/- 7 mmHg and from 27 +/- 2 to 31 +/- 3 mmHg respectively. These results may provide an explanation for the rapid improvement in patients' clinical symptoms such as angina pectoris and in stress electrocardiogram which have been observed during HELP therapy.  相似文献   
85.
目的探讨三叉神经痛(trigeminal neuralgia,TN)患者三叉神经患支内结缔组织改变与神经脱髓鞘的关系。方法对手术切取的TN患者三又神经患支标本及对照标本行髓鞘染色,在光镜及电镜下观察神经横截面形态改变,并采用图像分析仪进行半定量测量。结果形态观察及图像分析结果都显示TN患者三叉神经患支明显脱髓鞘,神经内结缔组织显著增生,F检验证实二者存在显著线性正相关。结论TN患者三叉神经惠支内神经内结缔组织增生,可能是TN发生的重要机制之一。  相似文献   
86.
目的探讨大鼠脂肪来源间充质干细胞(MSC)对大鼠肝移植术后急性排斥反应的作用。方法分离、培养SD大鼠MSC,体外混合淋巴细胞培养(MLC)体系中,研究MSC对Wistar大鼠T细胞增殖的抑制作用。以SD与Wistar大鼠为供受体建立肝移植模型。随机分为MSC处理组与空白对照组,术后第7天检测肝功能、血清白细胞介素(IL)-2和白细胞介素(IL)-10水平、肝组织病理形态及肝细胞凋亡。结果体外MLC中,Wistar大鼠T细胞增殖明显受抑,抑制率为48.44%。实验组血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、总胆红素(TBIL)、IL-2、IL-10分别为(134.2±45.0)、(162.5±30.5)U/L、(30.6±5.4)μmol/L、(187.35±18.26)、(193.95±37.62)μg/L;对照组上述指标分别为(355.6±54.3)、(296.4±71.2)U/L、(145.7±28.6)μmoL/L、(295.73±57.15)、(75.12±11.23)μg/L,两组差异有统计学意义(P<0.05);病检提示实验组排斥反应较对照组明显减轻;脱氧脲核苷酸缺口末端标记(TUNEL)检测提示实验组肝细胞凋亡程度明显低于对照组(P<0.05)。结论供体来源MSC能明显抑制MLC体系中受体源T细胞的增殖,并能显著减轻大鼠肝移植术后急性排斥反应。  相似文献   
87.
目的 探讨皮肤扩张器的定量扩张法在在耳廓再造中的应用,并对所发生的并发症进行处理.方法 选择50 ml肾形扩张器埋置于残耳后乳突区无毛发皮下,术后3 d拔除引流管,10d拆除缝线.术后7 d进行常规注水,每周3次,每次注水约5 ml,注水总量为60 ml左右.注水完毕后维持扩张1个月.结果 1992年1月至2006年12月共收治先天性小耳畸形患者5 248例,完成50ml肾形扩张器埋置6 252只.扩张器维持扩张完毕后可见扩张皮肤质薄、血管丰富.并发症有血肿、扩张器外露、创口裂开、感染等,发生率较低,约为7.79%.结论 皮肤定量扩张法操作简单、并发症较少,为耳廓再造提供了良好的无毛发、质薄、血供丰富可靠的皮肤.  相似文献   
88.
头皮脑回样病变畸形   总被引:3,自引:0,他引:3  
目的提高对头皮脑回样病变畸形的认识和治疗水平。方法复习有关文献,对头皮脑回样病变畸形的病因、临床表现、诊断、分类和治疗进行了分析,采用切除后植皮或扩张头皮瓣修复治疗6例。结果6例病变切除彻底,随访无复发。其中2例植皮病例患者导致局部秃发,4例扩张头皮瓣修复外形满意。结论头皮脑回样病变畸形是一种罕见的头皮良性病变,头皮扩张术是修复治疗头皮脑回样病变的理想方法。  相似文献   
89.
朱国献  徐梁 《中国美容医学》2007,16(11):1511-1512
目的:探求上唇外侧组织瓣在修复较大面积下唇缺损中的作用。方法:根据患者下唇缺损情况,设计上唇外侧组织瓣,旋转后插入缺损组织,同时在缺损吻合处,将上层外侧旋转瓣内侧粘膜肌肉向外牵拉形成部分新的红唇,然后逐层相对缝合,修复缺损。结果:自2003年1月应用此方法修复患者6例,术后随访1~2年,唇部外形好,无流涎,无口闭合不全,效果满意。  相似文献   
90.
Abstract Background and Aim: The prediction of soft tissue esthetics is important for achieving an optimal esthetic outcome in orthodontic treatment planning. Applicable procedures have so far been restricted to two-dimensional profile predictions that have not proven to be very reliable. The goal of this investigation was therefore to develop a novel finite element-based procedure that allows a three-dimensional, easily visualized, quantitative analysis and prediction of soft tissue behavior for the clinician. The procedure to be developed should be easy to handle and not entail any additional radiation exposure for the patient. Material and Methods: Using a three-dimensional scanner, the facial surfaces of 20 probands were digitalized and individual FEM models were generated. Results: After reduction of data redundancy via several conversion steps, a patient-specific simulation model was prepared consisting of 20,000 to 40,000 individual elements to which specific physical properties could be assigned. The average time required for generating a virtual model was 50 minutes. Problems occurring during model generation were rare (mainly shadowing phenomena and movement artifacts). Conclusion: The procedure outlined herein makes the reliable generation of patient-specific simulation models possible for facial soft tissue prediction in orthodontics.  相似文献   
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