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排序方式: 共有691条查询结果,搜索用时 15 毫秒
81.
目的:采用改进的掌板紧缩手术方法,以矫正手的爪状畸形,间接增强手指背伸肌力和指屈肌力。方法:在掌指关节处将掌板“H”形切开,远侧舌状瓣向近侧牵拉屈掌指关节与近侧瓣重叠缝合在人为制造的掌骨颈部的粗糙面上。结果:196例施行矫正手术,随访1~11年,除4例失败外,均矫正成功,外形良好,增强了手的抓握与夹捏力,无1例发生屈肌腱粘连。结论:本术式有效地矫正了爪状手的畸形 相似文献
82.
This study was conducted in two parts. In the first part, 20 single-rooted teeth that had been scheduled for extraction were investigated. The electronic root canal lengths were measured in vivo with a Dental Sono-Explorer type Y-III, and the actual canal lengths were measured after extraction of the teeth. The rate of agreement of the two measurements was 77.5% within a range of ±0.5 mm, while it was 100% at ±2.0mm, which is acceptable clinically. In the second part, there were 19 simulated canals whose lengths and apical foramen sizes were known beforehand. Experiments revealed a negative correlation between the areas of the apical foramina and the difference between the electronic and the actual root canal lengths. This relationship was shown by the linear regression equation: ?= 0.6 ? 1.6x. With the exception of the smallest areas of foramina, electronic root canal length measurements were less than the actual lengths. 相似文献
83.
广西黑斑蛙的染色体组型及Ag-NORs的研究 总被引:4,自引:1,他引:3
目的:对广西黑斑蛙的染色体组型及Ag-NORs进行研究。方法:采用骨髓细胞直接法制备染色体标本片及用核仁形成区的一步染色法进行银染。结果:本实验蛙的二倍体染色体2n=26。可配成13对同源染色体,其中大型5对,小型8对。在第8号染色体长臂中央具有明显次缢痕。Ag-NORs亦是在No.8,数目为2个。结论:广西黑斑蛙与国内其它地区同种蛙的染色体结构有差异。 相似文献
84.
U. Helmchen U. Kneissler J. F. Liard G. Peters 《Journal of molecular medicine (Berlin, Germany)》1972,50(17):841-844
Summary Unilateral nephrectomy and constriction of the remaining renal artery in the rat induced a sustained increase of systolic blood pressure, which becomes significant as soon as 90 minutes after operation, and a transient rise in renal venous as well as in peripheral plasma renin activity between 20 and 180 minutes after operation. Unilateral nephrectomyper se, after 90 and 180 minutes, caused a significant fall of the systolic blood pressure, a slight increase of renal venous renin activity after 20 and 45 minutes, and between 3 and 24 hours after operation it was followed by a significant decrease of peripheral plasma renin activity. An increased secretion of renin from the clamped kidney may thus contribute to the initial rise of blood pressure in rats with Goldblatt-type hypertension.Supported by Fonds National Suisse de la Recherche Scientifique, Grant No. 53153. 相似文献
85.
吗啡对非伤害性刺激后CCI大鼠脊髓c-fos表达的影响 总被引:3,自引:0,他引:3
目的 观察慢性坐骨神经收缩损伤 (CCI)大鼠触摸刺激后机械痛阈和热痛阈的变化 ,以研究吗啡 (2mg/kg)腹腔注射后对非伤害性刺激后脊髓后角c fos表达的影响 ,探讨脊髓痛觉调控机制。方法 选择雌性SD大鼠 30只 ,随机分为假手术组、CCI组和吗啡组 ,分别于术前 2d、术后 4、7、14d给予机械痛阈和热痛阈测试。大鼠处死前 3h给于非伤害性触摸刺激 ,处死后取脊髓切片 ,免疫组织化学方法检测c fos表达。结果 CCI组和吗啡组大鼠坐骨神经结扎 4d后均呈现不同程度的痛觉过敏 ,以术后 14d为甚 ,触摸刺激导致的脊髓c fos的表达明显增加 ,主要集中分布于脊髓背角表层Ⅰ~Ⅱ层的中间内侧部 ,Ⅴ~Ⅹ层也有一定程度增多。 2mg/kg腹腔注射不能有效的阻断慢性缩神经损伤大鼠痛觉过敏。吗啡组与CCI组相比c fos的表达无明显减少 ,两组相比差异无显著性意义 (P >0 0 5 )。结论 2mg/kg吗啡腹腔注射不能有效抑制非伤害性刺激诱发痛觉过敏以及脊髓背角c fos的表达 ,可能与吗啡用药途径和用量过小有关 ,也可能与脊髓背角二级感觉神经元兴奋性增高有关 相似文献
86.
Summary
Vascular surgery or penile prosthesis implantation are the main surgical options for erectile dysfunction. In this category,
penile revascularization is the only causal therapy for selected patients: males younger than 50 years of age at time of surgery,
maximum of two risk factors, exclusion of diabetes mellitus. Long-term success decreased to 53 % to 55 % in comparison to
first encouraging reports of 80 % success. Venous surgery resulted in an even more distinct decline of success the longer
the elapse of time after surgery. Long-term success dropped under 40 %, leaving only a few indications for penile venous ligation.
In contrast, penile prosthesis implantation results in high satisfaction rates. Despite this, it is not generally recommended
as first choice surgical management as it is linked to irreversible damage of the cavernosal bodies. Among numerous types
of penile implants, preference is nowadays mostly given to the three-piece hydraulic models. However, such complications as
defective or perforated cylinders in up to 35 % after 5 years have arisen, depending on the type of implant. In a selected
patient group, vacuum constriction devices with a mean patient acceptance of 75 % (50 % to 90 %) seldom result in complications
and are thus considered to be a well-established therapeutical option.
相似文献
87.
Ram S. Verma Jorge Rodriguez Harvey Dosik Uta Francke 《American journal of medical genetics. Part A》1981,8(1):17-25
Eighty normal American blacks were studied by the CBG technique (C-bands by barium hydroxide using Giemsa) for estimation of size and inversion heteromorphisms of chromosomes 1, 9, and 16, and the data were compared to those of whites using subjectively defined criteria. Size and inversion heteromorphisms were classified into 5 levels. The frequencies of size heteromorphisms of chromosomes 1 and 16 were 10.63% and 6.88%, respectively, which are not significantly different from those of a normal population of whites. A higher incidence of size heteromorphisms for chromosome 9 was noted in whites (47.5% vs 30%). The frequencies of inversion heteromorphism of chromosomes 1, 9, and 16 were 17.5%, 21.9%, and 0.0%, respectively. Overall, 61 chromosomes were found to have an inversion. Of these, 28 were in chromosome 1, and 33 were in chromosome 9. A higher incidence of inversion heteromorphisms of chromosomes 1 and 9 was noted in American blacks, while no inversions were found in chromosome 16 in either population. A significant association of increased size of the h region with inversion (r = 0.99 P < 0.01) is demonstrated, ie, enlarged h regions have a higher frequency of inversions. 相似文献
88.
目的采用门静脉部分缩窄法建立SD大鼠门静脉海绵样变性(CTPV)的动物模型,观察成模过程中门静脉压力、门静脉及周围组织的结构变化,为临床及基础研究提供可靠、稳定的模型动物。方法将SD大鼠100只,随机分为2组:假手术组和模型组,每组各50只。模型组用21G口径的钝头针对大鼠门静脉部分缩窄术;假手术组仅对门静脉进行游离探查,不进行缩窄。各组分别在术后1、2、3、4、6w随机取出10只,行门静脉测压、门静脉造影、病理学等观察门静脉及其周围组织侧支循环的形成情况。结果假手术组大鼠术后各时间段均未形成门脉高压,门静脉造影未见有侧支循环形成。模型组术后1w即形成门静脉高压,门静脉造影显示术后第3w,肝门区可见向肝性侧支循环,术后6w,门静脉区形成典型的海绵样变性。结论用21G钝针头行门静脉部分缩窄,可以复制出类似CTPV的大鼠模型。术后3w门静脉压力达到高峰,以后稍有下降并逐渐趋于稳定,在术后3w门静脉已出现向肝性侧支循环,到6w时形成典型的门静脉海绵样变性改变。 相似文献
89.
90.
Nobukazu Kuroda Junichi Yamanaka Toshihiro Okada Tadamichi Hirano Yuji Iimuro Jiro Fujimoto 《Journal of hepato-biliary-pancreatic sciences》2006,13(2):160-166