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61.
目的探讨脊髓纵裂分型治疗的疗效。方法对1978年5月至2006年11月收洽的有完整资料的121例单管型及双管型脊髓纵裂患者的病历资料进行回顾性分析,并通过临床神经功能评分及胫后神经皮层体感诱发电位(FTNCSEP)P40波峰监测,评价其手术及非手术治疗的疗效。结果所有患者均得到随访,随访时间6个月~15年,平均2年6个月。96例双管型患者中手术治疗86例,术后观察和随访发现24例痊愈、22例有明显改善、28例有一定改善、12例无明确效果,临床神经功能评分及PTNCSEP术后有明显改变,尤其是以疼痛为主诉的患者恢复最为明显,手术总有效率为86%;10例双管型患者未行手术治疗,随访发现临床症状无明显改善且有加重趋势。单管型患者25例,手术治疗16例,术前、术后临床神经功能评分及胛NCSEP无明显变化;未手术治疗的9例,随访时上述指标亦无明显变化。结论双管型脊髓纵裂患者脊髓损害重且呈进行性加重,精细的手术治疗可以使大多数患者症状得到缓解,终止神经进行性损伤,确诊后应尽早手术。单管型脊髓纵裂患者脊髓损害轻,无须手术探查。  相似文献   
62.
对60例输卵管结扎术后近段闭塞(间质部及峡部)妇女采用改良输卵管子宫角植入术,并对部分病例切除的近段输卵管标本进行病理形态学观察。病理检查发现:①输卵管慢性炎症;②输卵管子宫内膜异位症;③管腔内增生的纤维组织填塞。术后随访50例(83.33%),输卵管通畅46例(92%),宫内妊娠29例(58%),校正妊娠率为63.04%,宫外孕1例,表明宫角植入术用于此类结扎术后输卵管近段闭塞病例的复通有较好疗效。对此术式的关键点及术后宫内妊娠率与绝育年限、年龄、术后输卵管长度的关系作了分析。  相似文献   
63.
An extensive review of the currently available literature on primary fallopian tube carcinoma is presented. The role of vaginal ultrasonography and the importance of an aggressive evaluation of every tubal deformity is stressed. A staging system which takes into account recent data on the biology of this malignancy is proposed. We emphasize the largely underestimated importance of early lymphatic spread of this disease, necessitating a thorough staging laparotomy with pelvic and para-aortic lymph node sampling in the apparent early stages. The need for adjuvant treatment is obvious, but until now no firm data exist as to what the optimal strategy should be. We recommend that until more representative studies are available, ovarian carcinoma protocols should be used in clinical practice.  相似文献   
64.
A novel sutureless vascular connecting system, an assembly with a delivery rod, an introducing sheath, and a connecting device, was developed for easy implantation of small-caliber vascular grafts less than 2 mm in internal diameter. A microporous stainless tube (length 2 mm, external diameter 1.6 mm, wall thickness 65 µm, pore diameter 400 µm, pore-to-pore distance 500 µm) was designed to serve as a connecting device. The feasibility of the system was tested using two types of preliminary animal experiments. One animal model consisted of graft implantation into the rat abdominal aorta (1.5 mm in diameter). The connecting device was inserted into the proximal and distal ends of the aorta through the introducing sheath by pushing the delivery rod with the connecting device placed over it. Subsequently, the aortic segments were inserted into both ends of model grafts made of segmented polyurethane (1.8 mm in internal diameter) and were fixed with banding silk threads from the exterior. The procedure was completed within 20 min without requiring specialized microsurgery techniques. Blood leakage and obstruction did not occur. The second model consisted of an end-to-end anastomosis between rabbit common carotid arteries (2 mm in diameter), which was performed within several minutes of blood flow interruption. Scanning electron microscopy demonstrated that the luminal surface of the device was fully covered with endothelial cells (ECs) after 1 week as a result of transluminal ingrowth of native ECs through the micropores in the device. This endothelialization may prevent early thrombus-induced occlusion. This simple and “easy-to-learn” technique will promote the development of small-caliber arterial grafts, and furthermore, it may have potential for clinical application.  相似文献   
65.
本研究观察了碱性成纤维生长因子对胚胎神经干细胞生长和分化的影响。从孕 12 d大鼠胚胎神经管分离神经干细胞 ,进行体外培养 ,分为碱性成纤维生长因子组及对照组。培养过程中观察神经干细胞的生长 ,于培养第 3、5、10 d用免疫组化方法检测培养细胞神经元特异烯醇化酶和胶质纤维酸性蛋白的表达 ,以观察神经干细胞分化为神经元及神经胶质细胞的状况。碱性成纤维生长因子可明显地促进培养细胞的生长和分化。免疫组化细胞计数显示 ,培养第 3 d,特异烯醇化酶、胶质纤维酸性蛋白阳性细胞数均明显增加 ;培养第 5 d,特异烯醇化酶阳性细胞数是对照组的 1.9倍 ,胶质纤维酸性蛋白阳性细胞数为对照组的 1.6倍 ,前者表达增加明显 ;培养第 10 d,两者的阳性细胞数仍高于对照组 ,但增加不明显。不同培养时间的胞体最长突起长度也均高于对照组 ;胞体直径及表面积随培养时间延长而增大。说明 ,碱性成纤维生长因子既能促进胚胎神经干细胞的生长 ,也可促使其分化为神经元及神经胶质细胞 ,尤以神经元为明显  相似文献   
66.
冲击波致伤作用实验研究进展   总被引:2,自引:0,他引:2  
原发冲击伤是爆炸产生的冲击波直接作用于生物体而引起的。各种生物激波管和其它冲击波发生装置的研制大大促进了冲击波致伤作用的实验研究的开展。通过将多种动物、离体器官以及培养的细胞暴露于冲击波,获得了大量的原发冲击伤实验研究结果。作者在简述冲击波的基本物理学特征的基础上,着重概括了生物激波管研制和原发冲击伤实验研究方法及其主要进展。  相似文献   
67.
Data on the occurrence of neural tube defects in first-, second-, and third-degree relatives of probands were collected in a United States study. The proportions of affected individuals were 3.2%, 0.5%, and 0.17% respectively. These findings are compared to those from other recent North American studies, and differences are discussed. It is pointed out that accurate recurrence risk figures may not be available, and that caution should be used when counseling families with relatives who are affected with NTD.  相似文献   
68.
The thermolabile variant (677TT) of methylenetetrahydrofolate reductase (MTHFR) is a known risk factor for neural tube defects (NTDs). The relationship between a second MTHFR polymorphism (1298A→C) and NTD risk has been inconsistent between studies. We genotyped 276 complete NTD triads (mother, father and child affected with an NTD) and 256 controls for MTHFR 1298A→C. Our findings do not support a role for the 1298A→C polymorphism in NTDs (OR 0.85 (95% CI 0.49–1.47), p= 0.55), nor do we observe a combined effect with the 677C→T polymorphism. Electronic Publication  相似文献   
69.
A feasibility study was made to examine whether pressure measurements can be used to diagnose vascular obstructions in blood vessels. Distortion of a pressure wave due to an obstruction in an elastic tube was investigated theoretically and experimentally. Linear theory and the method of characteristics were employed in developing mathematical expressions for the distortion of the pressure wave. The quality of the models developed was examined by performing experiments on a latex tube with rigid obstructions. A nonlinear model using the method of characteristics was in good agreement with the experiment data for obstructions with any severity, while a linear model was applicable to small obstructions. The nonlinear model is proposed as a mathematical model for the detection of vascular obstructions by analysing pressure waves.  相似文献   
70.
An intimate arrangement between the utero-ovarian vein and the ovarian artery has been found in many species. The anatomical structure suggests the existence of a counter-current system of exchange, and many animal experiments point to a physiological importance of this transfer system. In man, the utero-ovarian vein forms a plexus around the ovarian artery. In-vitro experiments have demonstrated a local transfer of progesterone; in-vivo experiments have proved that krypton and progesterone can be transferred from the utero-ovarian vein to the ovarian artery. The physiological and pharmacological importance of the counter-current system is still under evaluation, and further investigations are needed. It has been suggested that counter-current transfer facilitates local communication between the ovary, Fallopian tube, and uterus. This may be important in a context of luteolysis, follicular selection and maturation, fertilization, and the recognition and maintenance of pregnancy. The pharmacological and therapeutic potential may be limited, as the ovarian adnexa are relatively difficult to access. Instillation of hormones into the uterine lumen will probably induce a higher plasma concentration in the ovarian arterial blood than in peripheral arterial plasma. A culdoscopic or endoscopic approach might permit introduction of long-acting depots in the uterine fundus near the Fallopian tubes and/or ovaries.  相似文献   
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