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1.
目的:神经断端保留小间隙的静脉桥接模拟神经外膜形成神经再生室,为周围神经再生创造了良好的生理环境,从而保证神经束的良好对合。实验采用部分脱乙酰甲壳质作为套管材料,用小间隙桥接方法修复坐骨神经损伤,观察套管内的神经再生情况,并与传统外膜缝合法进行比较。方法:实验于2001-01/2002-10在北京大学人民医院创伤骨科实验室完成。①主要材料:实验所用中空圆柱形套管为北京大学人民医院与中国纺织科学院共同发明的一种部分脱乙酰甲壳质生物套管(专利号:01136314.2)。实验中所用套管尺寸为:管长4 mm,壁厚0.1 mm,内径1.5 mm。②实验动物:健康成年雄性SD大鼠20只,随机分成2大组,每组10只,每一大组全部10只动物的左腿坐骨神经为一组,右腿坐骨神经为另一组,每组10根坐骨神经。另取5只同样大鼠双侧坐骨神经未做处理作为正常对照组。③实验方法:外膜原位缝合组:切断坐骨神经,显微镜下神经外膜原位缝合;生物套管小间隙原位桥接组:切断坐骨神经,显微镜下小间隙套管桥接;断端旋转180°外膜缝合组:切断坐骨神经,显微镜下远端旋转180°后,神经外膜缝合;断端旋转180°生物套管小间隙桥接组:切断坐骨神经,显微镜下远端旋转180°后,小间隙套管桥接。④实验评估:术后第7,14,21,28,42天取坐骨神经,进行免疫组织化学染色及观察。结果:再生神经延套管中央走行,7 d时已有部分纤维通过2 mm间隙,14 d时有髓纤维数量明显多于近端。21 d后,套管组与原位外膜组新生有髓神经纤维数相近。再生纤维胞核数量较多,髓鞘纤细。套管结构完整。结论:此种部分脱乙酰甲壳质生物套管内的再生神经连续、整齐,髓鞘完整,其神经再生情况好于传统外膜缝合法。  相似文献   
2.
Aluminum potassium sulfate and tannic acid injection (ALTA) is a useful and less-invasive treatment for internal hemorrhoids. However, it is not a treatment option for external hemorrhoidal diseases, including mixed hemorrhoids. Distal hemorrhoidectomy with ALTA injection involves surgical resection of external piles, followed by injection therapy on internal piles. We report technical details and the short-term results of this procedure in patients with mixed hemorrhoids. Seventy-two patients with mixed hemorrhoids treated between 2010 and 2011 were included. The main outcome measures were the short-term response and complication rates. At 28 days after surgery, the disappearance rate of prolapse was 100%. Three patients (4%) had postoperative complications, all minor in nature. No prolapse recurrence was observed within a median follow-up period of 6 months. Distal hemorrhoidectomy with ALTA injection appears to be a promising treatment option for patients with mixed hemorrhoids.Key words: Hemorrhoidectomy, Sclerotherapy, Aluminum potassium sulfate and tannic acidHemorrhoids are a very common anorectal condition, defined as the symptomatic enlargement and distal displacement of normal anal cushions. The most common symptom of hemorrhoids is anal bleeding and prolapse.1Hemorrhoidectomy is the most effective treatment for prolapsed hemorrhoids and is associated with the lowest recurrence rate. However, hemorrhoidectomy is not without complications, which include postoperative pain, urinary retention, secondary hemorrhage, formation of skin tags, anal stenosis, and fecal incontinence.2Aluminum potassium sulfate and tannic acid (ALTA) is an injectable sclerosant for treating hemorrhoids. In a comparative study of ALTA injection and hemorrhoidectomy for prolapsed hemorrhoid cases, ALTA injection produced almost the same effects as hemorrhoidectomy, without the specific complications.3,4 However, ALTA injection is effective only for internal hemorrhoids. In the case of mixed hemorrhoids with predominant external hemorrhoids or thrombosed hemorrhoids, application of ALTA is not appropriate.3,5Distal hemorrhoidectomy with ALTA injection (DHA) is another option for the management of mixed hemorrhoids. The procedure involves surgical resection of the external piles, followed by ALTA injection on the remaining internal piles. This study aimed to describe the technical details and evaluate the short-term response and complication rates in patients with mixed hemorrhoids treated with this combined approach.  相似文献   
3.
Transient elastography (TE) is a novel, non-invasive imaging technique for measuring liver stiffness (LS). It is considered to be useful for predicting the severity of fibrosis and the risk of cirrhosis or hepatocellular carcinoma. However, the association between the presence of diffuse regions of increased cell density in the liver and elevated LS values has not been assessed. We experienced a case in which a mature T-cell neoplasm had invaded the liver, but the infiltrating lesion was not detected by contrast-enhanced computed tomography (CT) or fluorodeoxyglucose positron emission tomography/CT scans. Instead, the tumor’s presence was indicated by the change in the patient’s TE-derived LS values after chemotherapy. At diagnosis liver dysfunction was detected in a biochemical examination, and mean LS value was as high as 25.4 kPa [interquartile range (IQR): 0.3, success rate (SR):100%]. After chemotherapy, the patient’s mean LS value fell to 4.3 kPa (IQR: 0.8, SR:100%). A follow-up pathological investigation demonstrated that proliferating abnormal T-cells were no longer present in the patient’s liver. This is the first report to describe the use of LS data to support a diagnosis of liver infiltration by tumor cells exhibiting a portal and sinusoidal distribution pattern rather than a focal pattern. Elevated TE-derived LS values should lead to hepatic tumor infiltration being considered during initial examinations or a suspicion of recurrence during follow-up examination of lymphoma patients who achieve complete remission, even when radiological investigations do not detect abnormalities in the liver.  相似文献   
4.
目的:已有实验研究证明,移植骨髓来源内皮祖细胞可以促进球囊损伤后血管内皮的修复及抑制内膜的增生.那么移植骨髓来源内皮祖细胞对自体静脉移植术后静脉血管内皮修复和内膜增生是否起同样的作用?观察自体骨髓来源内皮祖细胞移植对自体静脉移植术后静脉桥血管再内皮化及内膜增生的作用。方法:实验于2007-01/08在北华大学附属医院内科实验室完成。实验室级别:P2级。①实验材料:6~8月龄雄性新西兰大白兔由解放军第二军医大学实验动物中心提供.体质量(2.5±0.5)kg,清洁级,实验过程中对动物处置符合动物伦理学标准。②实验方法:抽取成年兔骨髓分离制备骨髓单个核细胞,体外扩增法培养出骨髓来源内皮祖细胞.在培养第7天通过Ac-Dil-LDL、FITC-BS-1双染色及流式细胞仪检测CD34、CD133、FIK-1表达进行细胞鉴定,应用DAPI荧光染料体外标记培养7 d的骨髓来源内皮祖细胞、将成年新西兰大白兔23只随机分为细胞移植组(n=13)和对照组(n=10)进行自体左颈外静脉、颈总动脉移植术,在建模后第3天将DAPI标记的骨髓来源内皮祖细胞悬液经耳缘静脉植入细胞移植组动物体内,埘照组植入等量的PBS液③实验评估:细胞移植后4周.观察兔静脉移植段血管性及内膜厚度。结果:23只免均进入结果分析,无脱落:①通过体外扩增法培养的骨髓来源内皮组细胞,培养至7 d可见AC-Dil-LDI及FITC-BS-1双染色阳性细胞并表达CD34、CD133及FIK-1。②在呈绿荧光染色的血管内皮中可见有部分不均匀的散发蓝色荧光(DAPI标记细胞的细胞核)。③细胞移植组兔静脉血管内皮有DAPI标记的细胞.且内膜厚度明显低于对照组(P<0.05)结论:自体骨髓来源的内皮祖细胞移植可以促进损伤部位血管内皮的修复.并抑制内膜的过度增生。  相似文献   
5.
Bolus injection of adenosine triphosphate (ATP) or adenosine is widely used clinically for terminating supraventricular tachycardia. However, bolus injection of these drugs has been reported to provoke atrial fibrillation (Afib). The effects of ATP and adenosine on the monophasic action potential duration (MAPD) of atrial and ventricular muscle was investigated, as well as the changes in the spatial distribution of atrial functional refractoriness caused by adenosine. Bolus injection of ATP and adenosine shortened atrial MAPD; no change was observed in the ventricle. Because local f-f intervals during atrial fibrillation correlate with the atrial refractory period, changes in mean f-f intervals in the right atrial appendage, His bundle region, coronary sinus ostium and distal coronary sinus were compared before and after injection of adenosine during induced Afib. Maximal shortening of f-f intervals was observed in the right atrial appendage. Inhomogeneous shortening of atrial refractoriness may account for the Afib following bolus injection of ATP or adenosine.  相似文献   
6.
7.
Platelet-derived growth factor promotes polymorphonuclear leukocyte activation   总被引:13,自引:0,他引:13  
Tzeng  DY; Deuel  TF; Huang  JS; Senior  RM; Boxer  LA; Baehner  RL 《Blood》1984,64(5):1123-1128
The platelet-derived growth factor (PDGF) has several well defined important biologic activities. Platelet-derived growth factor is the major mitogen in human serum for cells of mesenchymal origins; it is a potent chemoattractant protein for human monocytes, neutrophils, fibroblasts, and smooth muscle cells; and has been implicated in transformation by simian sarcoma virus and perhaps in transformation by other agents as well. In this article, PDGF has been shown to stimulate activation of human peripheral blood neutrophils defined by loss of membrane associated calcium as reflected by loss of chlortetracycline fluorescence, release of superoxide anion and specific granule enzymes, and enhanced neutrophil adherence and aggregation. These responses occurred in a dose-dependent fashion at concentrations of PDGF between 10 ng/mL (0.4 nmol/L) and 40 ng/mL (1.5 nmol/L) and were comparable to effects obtained with optimal concentrations of fMLP and C5a. Degranulation induced by PDGF was selective for secondary (specific) granules and not primary (azurophil) granules. Platelet-derived growth factor thus is ideally suited for a pivotal role in attracting inflammatory cells locally and initiating neutrophil activation at sites of blood vessel injury. Platelet-derived growth factor or a closely related protein also may play an important role in attracting and activating neutrophils in association with inflammatory tumors.  相似文献   
8.

BACKGROUND:

Diagnosing pulmonary tuberculosis (PTB) is challenging in patients who are unable to spontaneously expectorate. Published evidence suggests that induced sputum (IS) is the least invasive and most cost-effective method of diagnosis, and should be used before fibre-optic bronchoscopy (FOB).

METHODS:

The medical records of 337 adults treated for PTB in northern Alberta between 1997 and 2007 were reviewed to determine whether local practice patterns reflect the evidence. Microbiological data were collected from the Provincial Laboratory for Public Health. Demographic information was collected from the patients’ charts.

RESULTS:

A total of 8.5% (26 of 307) of PTB patients had IS collected, whereas 35.8% (110 of 307) underwent FOB. Among FOB patients, 56.4% (62 of 110) had no sputum sent before the procedure and 29% (18 of 62) of these patients were smear positive. Only five patients referred for FOB had IS sent previously. There were no demographic factors predictive of IS use, whereas being an inpatient at a teaching facility or having a nodule or mass on chest x-ray was predictive of FOB referral. Because so few IS samples were available, not all patients had spontaneously expectorated sputum, IS and FOB tests performed; thus, the calculated yields were not comparable with one another.

CONCLUSIONS:

Despite published evidence recommending IS collection before FOB referral in suspected PTB patients, clinicians in our health region appeared to prefer early FOB over IS by a large margin. This practice pattern is less cost effective and exposes patients and health care workers to greater risk. Further research is needed to identify the reasons for the underuse of sputum induction.  相似文献   
9.
To compare the effects of class Ic and III antiarrhythmic agents on the termination and prevention of atrial fibrillation, the present study investigated the use-dependent electrophysiological effects of flecainide, nifekalant and d,l-sotalol on the human atrium. Flecainide significantly prolonged effective refractory period (ERP), intra-atrial conduction time (IACT) and monophasic action potential duration (MAPD), and its effects on ERP and IACT were use-dependent. Nifekalalant significantly prolonged ERP and MAPD, and these effects were reverse use-dependent; however, there was no significant change in IACT. d,l-Sotalol significantly prolonged MAPD and the effect was reverse use-dependent. It significantly prolonged ERP, but the effect was not reverse use-dependent. d,l-Sotalol increased IACT in a use-dependent manner. Thus, for atrial fibrillation, class Ic antiarrhythmic agents might be more effective in termination and class III antiarrhythmic agents might be more effective in prevention.  相似文献   
10.
Relationship between the fecal occult blood test and benign anal disorders   总被引:1,自引:0,他引:1  
BACKGROUND/AIMS: The fecal occult blood test is a very useful method for mass screening for colorectal cancer. The possibility of the fecal occult blood test being positive is high even in benign anal disorders, but the relationship between anal disorders and the fecal occult blood test has not been fully studied. METHODOLOGY: During the period from November 1995 to April 1996, we performed both fecal occult blood test and sigmoid colonofiberscopy for 440 patients with anal disorders who visited our hospital for the first time. RESULTS: The positive fecal occult blood test rate was 18.8% (77/409) for those who had only anal disorders and no findings in the colon and rectum. The positive fecal occult blood test rate was significantly high in the cases with polyps (42.3%) and in those with colorectal cancer (60%). CONCLUSIONS: These findings suggested the need to analyze fecal occult blood test, keeping in mind that fecal occult blood test might be positive even without any malignant findings in the large intestine in about 20% of cases of patients have anal disorders when fecal occult blood test is performed.  相似文献   
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