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51.
目的 探讨食管癌颈部吻合术中前壁单层吻合的临床应用价值 ,并与同期荷包状食管胃吻合法 (前壁双层吻合法 )相比较。方法 对 32 1例食管癌行根治性切除及食管胃颈部吻合术 ,其中前壁双层吻合 16 1例 ,前壁单层吻合16 0例。结果 双层吻合术中 ,吻合口瘘 5例 (3.13% ) ,随访 137例 ,吻合口直径 <0 .5 cm者占 5例 (3.5 % ) ,0 .5 - 1cm者70例 (5 0 .9% ) ,1cm以上者 6 2例 (4 5 .6 % ) ,单层吻合术中 ,吻合口瘘 7例 (4 .38% ) ,随访 131例 ,吻合口直径 <0 .5 cm者无 1例发生 ,0 .5 - 1cm者 5 3例 (4 0 .8% ) ,>1cm以上者 78例 (5 9.2 % )。结论 食管癌颈部吻合术中 ,前壁单层吻合能减少吻合口狭窄 ,改善术后病人的生活质量 ,而吻合口瘘发生率无明显增加。 相似文献
52.
Objective:To study whether adenovirus-mediated human β-nerve growth factor (Ad-hNGFβ) gene has any protective effect on blast hearing impairment. Methods:Deafness was induced by blast exposure (172.0 dB) in 30 healthy guinea pigs. On day 7 of blast exposure, Ad-hNGFβ was infused into the perilymphatic space of 20 animals as the study group (hNGFβ group), and artificial perilymph fluid (APF) was infused into the perilymphatic space of the other 10 animals as the control group. At weeks 1, 4 and 8 after blast exposure, the animals were sacrificed and the cochleae were removed for immunohistochemical and HE stainings. Results: Expression of Ad-hNGFβ protein was detected in each turn of the cochlea at the 1st week, with almost equal intensity in all turns. At the 4th week, the reactive intensity of the expression of Ad-hNGFβ protein decreased. At the 8th week, no expression was detectable. The results of HE staining showed that the amount of spiral ganglions in hNGFβ group was significantly greater than that of the control group at week 4 (P〈0.01). Conclusion: Ad-hNGFβ can be expressed at a high level and for a relatively long period in the blast impaired cochlea, suggesting that Ad-hNGFβ has a protective effect on cochlear spiral ganglion cells after blast exposure and the efficient gene transfer into cochlea had been achieved without toxicity. 相似文献
53.
目的:观察病房康复延伸护理对脑卒中迟缓性偏瘫患者三维步态时空参数的影响。方法:将60例脑卒中迟缓性偏瘫患者随机分为常规护理组(A组,n=30)、病房康复延伸护理组(B组,n=30)两组,予以相应的方法治疗8周,评估治疗前后两组患者三维步态时空参数。结果:与治疗前相比,治疗后两组患者的步长、步幅、步速、步频、支撑相、双支撑相等参数及B组摆动相均有不同程度的改善(P<0.05); A组摆动相和步宽及B组步宽的变化差异无统计学意义(P>0.05)。与治疗后A组比较,治疗后B组的步长、步幅、步速、步频、支撑相、双支撑相等参数改善较为明显(P<0.05),步宽和摆动相的改善差异无统计学意义(P>0.05)。结论:病房康复延伸护理能改善脑卒中迟缓性偏瘫患者三维步态时空参数,具有临床意义。 相似文献
54.
55.
一种可生物降解温度敏感型聚乙二醇-聚己内酯-聚乙二醇水凝胶的合成和表征 总被引:1,自引:0,他引:1
合成了一系列分子量较低的聚乙二醇.聚己内酯-聚乙二醇(Poly(ethylene glycol)-Polycaprolactone-Poly(ethylene glycol),PEG-PCL—PEG)三嵌段共聚物。分别采用FTIR和1H—NMR对其结构进行了表征。所合成的PEG-PCL-PEG共聚物具有良好的水溶性,当水溶液浓度高于临界凝胶浓度(Critical gel concentration,CGC)时,随着温度的变化聚合物水溶液会呈现特有的凝胶-溶胶转变。研究了共聚物亲水疏水链段的比例和长度,以及热历史等对凝胶-溶胶转变行为的影响。通过调节上述条件,可以在一定程度上拓宽凝胶-溶胶转变温度范围,有助于PEG—PCL-PEG水凝胶在可注射药物控制释放系统等方面的应用。 相似文献
56.
本文借助电子显微镜技术对 4月胎龄组及 6月胎龄组水囊引产胎儿海马中段部位的凋亡神经元超微结构进行观察、拍照 ,并对结果进行了分析讨论。结果显示 :两组对象中均可见凋亡神经元 ,所见的凋亡神经元的超微结构变化基本相同 ,即细胞核内有明显的染色质边集和凝结成块的现象 ,并可见核膜皱缩和扭曲。另外 ,6月组凋亡细胞的结构变化较 4月组更为明显。在 6月组细胞质内和核内均有小体出现 ,其他细胞器无显著变化。从而更进一步说明在胚胎海马发育中存在着神经元不同性质的死亡现象 -即正常死亡和凋亡。而且提出 6月组显现出更为明显的凋亡神经元形态变化 相似文献
57.
Proximal tubular epithelial cell integrins respond to high glucose by altered cell-matrix interactions and differentially regulate matrixin expression 总被引:11,自引:0,他引:11
Karamessinis PM Tzinia AK Kitsiou PV Stetler-Stevenson WG Michael AF Fan WW Zhou B Margaritis LH Tsilibary EC 《Laboratory investigation; a journal of technical methods and pathology》2002,82(8):1081-1093
Thickening of the tubular basement membrane (TBM) occurs in diabetic nephropathy, but the effects of high glucose on the functional aspects of proximal tubular epithelial cells are not clearly understood. In the present study, we examined the effects of elevated glucose concentrations on (a) integrin expression by human proximal tubular epithelial cells (HK-2) and integrin-mediated interactions with type IV collagen (colIV) and laminin, major components of TBM; (b) the expression of matrixins/matrix metalloproteinases (MMPs), which is regulated by integrins; and (c) the expression of tissue inhibitors of metalloproteinases (TIMPs). HK-2 cells cultured in 25 mM glucose underwent a reduction of the expression of alpha3, beta1, alpha(v)beta3, and alpha5 integrin subunits, with a concomitant increase of the alpha2 subunit, compared with cells grown in 5 mM glucose. Adhesion experiments demonstrated that high glucose led to increased cell adhesion on either colIV or laminin. Experiments of competition of adhesion using anti-integrin antibodies indicated that HK-2 cells in 5 mM glucose used mainly alpha(v)beta3 and alpha5beta1 integrins to adhere to colIV, whereas in 25 mM glucose they additionally used alpha2beta1. In the case of laminin, a beta1-mediated adhesion was observed when HK-2 cells were in 5 mM glucose, whereas in 25 mM glucose, alpha2beta1 and alpha(v)beta3 were also involved. Elevated glucose concentrations resulted in decreased expression of MMP-9 and MMP-2, whereas an increase in TIMP-1 and a decrease in TIMP-2 expression were observed. We also examined which integrins mediated the expression and secretion of matrixins MMP-2 and MMP-9. Ligation of alpha3beta1 with mAbs resulted in induction of MMP-2 expression and secretion, whereas antibody ligation of alpha(v)beta3 led to down-regulation of MMP-9. The above data implicate integrins of proximal tubular epithelial cells in the regulation of MMPs and in the development of TBM thickening in diabetic nephropathy. 相似文献
58.
耳穴电参数时变关系实验表明,在测量起始t<2τ时,因瞬变作用,电位E(t)和压降U(t)为瞬态响应,响应函数呈指数关系,特征参数为弛豫时间τ,τ≈RC;t>2τ时,为时变间期。电路分析给出数学描述,并与耳穴和模拟实验结果较相符。提示,时变特征应以t>2τ后提取,静态电测量时,采样应避开瞬变期,可提高准确性。该工作对正确鉴别时变性和特征提取,全面认识耳穴电特性具有重要意义。 相似文献
59.
Han Lü Sixun Zheng Bing Zhang Xiaozhen Tang 《Macromolecular chemistry and physics.》2004,205(6):834-842
Summary: The blends of poly(hydroxyether sulfone) (PHES) with poly(N‐vinylpyrrolidone) (PVPy) were investigated by means of differential scanning calorimetry (DSC) and FTIR spectroscopy. The miscibility of the blend system was established on the basis of the thermal analysis results. DSC showed that the PHES/PVPy blends prepared by casting from N,N‐dimethylformamide (DMF) possessed single, composition‐dependent glass transition temperatures, indicating that the blends are miscible in the entire composition. The experimental glass transition temperatures have higher values than those calculated on the basis of additive behavior; the variation of the glass transition temperatures of the blends was accounted for by the Kwei equation. FTIR studies indicate that competitive hydrogen bonding interactions exist upon addition of PVPy to the system, which were involved in the self‐ and cross‐association, i.e., ? OH···O?S, ? OH···OH of PHES and ? OH···O?C< of PVPy. The FTIR spectra in the range of the sulfonyl stretching vibrations showed that the hydroxyl‐associated sulfonyl groups are partially “set free” upon addition of PVPy to the system. The IR spectroscopic investigation of both the model compounds and the PHES/PVPy blends suggests that the strength of the hydrogen bonding interactions in the blend system increases in the following order: ? OH···O?S, ? OH···OH and ? OH···O?C<.
60.
Encoding of electrical, thermal, and mechanical noxious stimuli by subnucleus reticularis dorsalis neurons in the rat medulla 总被引:2,自引:0,他引:2
1. In anesthetized rats, recordings were made within the medullary subnucleus reticularis dorsalis (SRD) from neurons that exhibited convergence of nociceptive inputs from the entire body. Neurons with total nociceptive convergence (TNC) responded to suprathreshold percutaneous electrical stimuli (2-ms duration) with an early and a late peak due to activation of A delta- and C-fibers, respectively, no matter which part of the body was stimulated. Neurons with partial nociceptive convergence (PNC) responded to the same stimuli with an A delta-peak regardless of which part of the body was stimulated and with a C-peak of activation from some, mainly contralateral, parts of the body. The characteristics of the responses of these neurons to the application of graded intensities of electrical, thermal, and mechanical stimuli were analyzed. 2. All TNC neurons and 85% of PNC neurons responded to A delta- and C-fiber activation following percutaneous electrical stimulation of the contralateral hindpaw. With regard to A delta-fiber-evoked responses, a linear relationship between the logarithm of the applied current and the magnitude of the responses was found within the 0.25- to 6.0-mA and 0.5- to 24-mA ranges for TNC and PNC neurons, respectively; however, these curves were essentially similar. With regard to C-fiber-evoked responses, such a linear relationship was found within the 1.5- to 6.0-mA range for both types of SRD neurons, although the TNC neurons presented larger C-fiber-evoked responses than did the PNC neurons. 3. TNC and PNC neurons linearly increased their discharges during the application of noxious thermal stimuli to the contralateral hindpaw within the range 44-52 degrees C; the mean responses evoked by noxious heat from TNC neurons were of higher magnitude than those from PNC neurons. The majority of SRD neurons presented long-lasting afterdischarges, especially with the highest temperature employed (52 degrees C). 4. TNC neurons monotonically increased their discharges during graded mechanical or thermal stimulation of the tail. When mechanical stimuli were applied, a linear relationship was found between the logarithm of the strength of the mechanical stimulus and the neuronal discharges, in the 5.3- to 7.4-N/cm2 range. With thermal stimulation, TNC neurons linearly increased their discharges in the 44-52 degrees C range. When increasing amounts of the tail were immersed in a 50 degrees C waterbath, TNC neurons increased their discharges within a restricted range of tail surface areas (0.9-5.7 cm2); further increases in the stimulated surface size were not followed by increases in firing rate.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献