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排序方式: 共有17条查询结果,搜索用时 178 毫秒
1.
无论是正常还是病生理条件下女性尿道的闭合机制还未完全了解清楚。近10余年来,尿道压声反射测量(UPR)得以发展并主要应用于女性压力性尿失禁。UPR利用声波反射检测的原理连续测量整个尿道的压力和相应的截面积,其最大优势在于检测时不改变尿道的自然形状和走向,遵循物理定律。这是常用的检测手段如尿道压力分布测定(UPP)难以实现的。本文介绍了该方法和有关UPR的相关研究,在男性和女性其它尿道疾病应用的可能性及其发展趋势。  相似文献   
2.
In gonococci-infected transduced human urethral epithelial cells (THUEC), the role of ERK, a mitogen-activated protein kinase (MAPK), in apoptosis is unknown. We observed lowering of ERK activation in THUEC following infection with anti-apoptosis-inducing Neisseria gonorrhoeae strain CH811. An isogenic cell division mutant of this strain, Ng CJSD1 (minD deficient), which is large and abnormally shaped, reduced ERK phosphorylation levels even more than its parental strain in THUEC. This led to higher anti-apoptosis in mutant-infected cells as compared to the parental strain-infected cells. Our results suggest that N. gonorrhoeae infection reduces ERK activation in THUEC contributing to anti-apoptosis.  相似文献   
3.
The collection of semen from tomcats by urethral catheterization (CT) after medetomidine administration offers a novel and easy approach to obtain good quality sperm for in vitro fertilization. This study was designed to compare the sperm quality parameters and in vitro fertilizing capacity of CT spermatozoa with those of spermatozoa retrieved after epididymal slicing (EP). Semen was collected in seventeen adult cats by urethral catheterization, after which the cat was orchiectomized. Motility, morphology, plasma membrane integrity, acrosomal status, and in vitro fertilizing capacity of both fresh CT and EP samples were evaluated. The results showed that both total and progressive motility, as well as the percentage of normal spermatozoa, were higher for EP sperm than for CT sperm (P < 0.01). Epididymal sperm had a lower percentage of spermatozoa with an intact acrosome (P < 0.01), while CT sperm contained more spermatozoa with tail abnormalities (P < 0.01). Other morphological parameters, as well as plasma membrane integrity, did not differ (P > 0.05) between CT and EP sperm. Nevertheless, no difference (P > 0.05) in in vitro fertilizing capacity between spermatozoa collected by means of the two different methods was found. In conclusion, semen collection by means of urethral catheterization after medetomidine administration yields fertilization results similar to epididymal slicing, despite the fact that several sperm variables were different. Since this novel catheterization technique is repeatable, is easy to perform and facilitates semen preparation protocols, it may be preferable for routine IVF experiments with fresh spermatozoa.  相似文献   
4.
Incomplete urethral tubularization (hypospadias) and anorectal abnormalities are two common and poorly understood birth defects that affect the extreme caudal midline of the human embryo. We now show that cell surface molecules essential for proper axon pathfinding in the developing nervous system, namely ephrin-B2 and the ephrin receptors EphB2 and EphB3, also play major roles in cell adhesion events that tubularize the urethra and partition the urinary and alimentary tracts. Mice carrying mutations which disrupt the bidirectional signals that these molecules transduce develop with variably penetrant severe hypospadias and incomplete midline fusion of the primitive cloaca. We further show that animals completely lacking ephrin-B2 reverse signaling present a fully penetrant failure in cloacal septation. This results in severe anorectal malformations characterized by an absence of the terminal-most hindgut (rectum) and formation of a fistula that aberrantly connects the intestines to the urethra at the base of the bladder. Consistent with an apparent requisite for both forward and reverse signaling in these caudal remodeling events, EphB2 and ephrin-B2 are coexpressed at the midline in the fusing urethral/cloacal endoderm and underlying lateral mesoderm of the urorectal septum that migrates toward the caudal midline as the cloaca septates. Our data thus indicate that B-subclass Eph and ephrin molecules play an important role in these clinically significant midline cell-cell adhesion and fusion events.  相似文献   
5.
测量排尿过程中的声音信号来诊断膀胱出口梗阻BOO。建立了一个三维的CFD模型,用来研究漩涡与梗阻的关系。通过计算都得到了各种情况下尿道内部的流场分布。比较计算结果可知,漩涡的大小主要由阻塞程度决定,其次还受膀胱压力的影响。计算结果对于完善这种声学无侵入诊断方法具有参考意义。  相似文献   
6.
王忠新  符伟军  洪宝发 《生物磁学》2011,(14):2783-2785
尿道损伤一直是个棘手的泌尿外科常见疾病。逆行尿道造影是评价尿道损伤的金标准。尿道损伤的治疗方法的选择在泌尿系创伤中是争议最多的。目前没有一种方法是最简单有效的处理方法。组织工程技术的诞生和发展,给尿道损伤的处理带来了新的希望,有望为尿道损伤的修复提供新的材料。本文仅就尿道损伤疾病的基本概况及国内外在诊断和治疗方面的的研究现状作简要综述。  相似文献   
7.
Introduction of urethral warmers to aid cryosurgery in the prostate has significantly reduced the incidence of urethral sloughing; however, the incidence rate still remains as high as 15%. Furthermore, urethral warmers have been associated with an increase of cancer recurrence rates. Here, we report results from our phantom-based investigation to determine the impact of a urethral warmer on temperature distributions around cryoneedles during cryosurgery. Cryoablation treatments were simulated in a tissue mimicking phantom containing a urethral warming catheter. Four different configurations of cryoneedles relative to urethral warming catheter were investigated. For each configuration, the freeze–thaw cycles were repeated with and without the urethral warming system activated. Temperature histories were recorded at various pre-arranged positions relative to the cryoneedles and urethral warming catheter. In all configurations, the urethral warming system was effective at maintaining sub-lethal temperatures at the simulated surface of the urethra. The warmer action, however, was additionally demonstrated to potentially negatively impact treatment lethality in the target zone by elevating minimal temperatures to sub-lethal levels. In all needle configurations, rates of freezing and thawing were not significantly affected by the use of the urethral warmer. The results indicate that the urethral warming system can protect urethral tissue during cryoablation therapy with cryoneedles placed as close as 5 mm to the surface of the urethra. Using a urethral warming system and placing multiple cryoneedles within 1 cm of each other delivers lethal cooling at least 5 mm from the urethral surface while sparing urethral tissue.  相似文献   
8.
本文对我国所产13种鼠科啮齿类进行了阴茎形态学的比较研究(包括阴茎骨和软体结构),探讨了在鼠科的家鼠属(Rattus)、姬鼠属(Apodemus)、小家鼠属(Mus)和巢鼠属(Micromys)4个属间以及同属不同种之间的差异。结果表明,阴茎的形态结构具有属和种的特异性和稳定性,可以为分类学的研究提供重要依据。  相似文献   
9.
Summary The distal segment of the human male urethra, in particular the fossa navicularis, was studied with light- and electron microscopy as well as by means of histochemical and immunocytochemical methods. The fossa navicularis of the urethra contains a circumscribed zone of extremely thick, non-keratinized stratified squamous epithelium composed of cells containing a large amount of glycogen. These cells lack acid phosphatase activity and lysozyme-like immunoreactivity, both of which can be demonstrated to varying extents in the other zones of the distal male urethra. These glycogen-rich cells are considered to be the substrate for an endogenous flora of lactobacteria, whereas the acid-phosphatase activity and the lysozyme-like immunoreactivity indicate the presence of macrophages and the secretion of bactericidal agents at the epithelial surface. These observations suggest that the different zones with heterogeneous properties in the distal male urethra probably represent a defense system against the invasion of pathogenic microorganisms. Moreover, the glycogen-rich zone, which resembles the glycogen-rich epithelium of the vagina, is estrogen-dependent. This is demonstrated in cases of sex reversal in which after long-lasting estrogen treatment the glycogen-rich zone becomes extremely extended by displacement of the neighbouring epithelium.  相似文献   
10.
Summary Sex reversed mice heterozygous for the X-linked Tfm mutation are mosaics with respect to the Tfm locus. In the androgen-dependent striated urethral muscle, nuclei coding for the intact testosterone receptor protein and nuclei coding for the defective Tfm receptor protein are incorporated in the same multinucleate muscle fibres. The intact testosterone receptor complex can thus be expected to enter the Tfm nuclei. Our measurements show that the fibre diameters of the mosaic muscle form a homogeneous population, intermediate in size between induced male and non-inducible Tfm phenotypes. By contrast, the nuclear size shows a bimodal distribution, the subpopulations corresponding to Tfm and wild type nuclei. The results indicate that the Tfm nuclei are not activated by the intact testosterone receptor complex.  相似文献   
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