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21.
22.
目的:检测转化生长因子β1在腹膜透析大鼠腹膜内表达,并探讨其在腹膜纤维化中的意义。方法:实验于2005-06/2006-03在中南大学湘雅二医院肾内科实验室完成。①实验材料:雄性SD大鼠,体质量180~240g,由中南大学湘雅二医院动物实验中心提供。②实验方法:将28只大鼠按随机数字表随机分为4组,每组7只。正常对照组不予任何干预;生理盐水组腹腔注射20mL生理盐水;低糖透析液组腹腔注射20mL1.5%葡萄糖透析液;高糖透析液组腹腔注射20mL4.25%葡萄糖透析液,均为1次/d。4周后,向大鼠腹腔注射4.25%葡萄糖腹膜透析液20mL,4h后于大鼠右下腹缓慢插入带有多个侧孔的10号静脉留置针,缓慢低位引流腹透液,量取引流液。③实验评估:取大鼠壁层腹膜组织,以苏木素-伊红染色,镜下测量腹膜厚度,采用免疫组织化学方法检测大鼠腹膜中转化生长因子β1及纤连蛋白。结果:28只大鼠均进入结果分析。①高糖透析液组、低糖透析液组超滤量均明显低于正常对照组与生理盐水组,并且高糖透析液组超滤量明显少于低糖透析液组(P均<0.05)。②高糖透析液组腹膜明显增厚,表面粗糙,间皮细胞肿胀,脱落,间皮下有大量血管生成以及胶原纤维沉积,还可见单核细胞等炎症细胞浸润,与其他组比较,腹膜厚度明显增加(P<0.05)。③高糖透析液组转化生长因子β1、纤连蛋白表达量均明显高于其他组;低糖透析液组转化生长因子β1、纤连蛋白表达量均明显高于正常对照组与生理盐水组(P<0.05)。④大鼠腹膜组织转化生长因子β1蛋白与纤连蛋白表达量、腹膜厚度之间呈明显的正相关(r=0.86,0.83,P<0.05)。结论:葡萄糖透析液可诱导腹膜组织转化生长因子β1明显上调,腹膜转化生长因子β1高表达与腹膜透析腹膜纤维化密切相关。 相似文献
23.
24.
Analysis of the steroidogenic acute regulatory protein (StAR) gene in Japanese patients with congenital lipoid adrenal hyperplasia 总被引:1,自引:0,他引:1
Nakae J; Tajima T; Sugawara T; Arakane F; Hanaki K; Hotsubo T; Igarashi N; Igarashi Y; Ishii T; Koda N; Kondo T; Kohno H; Nakagawa Y; Tachibana K; Takeshima Y; Tsubouchi K; Strauss JF rd; Fujieda K 《Human molecular genetics》1997,6(4):571-576
Genomic DNA from 19 Japanese patients with congenital lipoid adrenal
hyperplasia (lipoid CAH) representing 16 different families was examined to
identify the genetic alterations of steroidogenic acute regulatory protein
(StAR). Ten of 19 patients had a 46,XX karyotype and nine had a 46,XY
karyotype. Six of the 46,XX patients have experienced spontaneous pubertal
changes including breast development and irregular menstruation whereas
none of the 46,XY subjects displayed pubertal changes. Eight different
mutations were identified. Sixteen patients were either homozygotes or
compound heterozygotes for the Q258X mutation. The seven other mutations
identified were 189delG, 246insG, 564del13bp, 838delA, Q212X, A218V and
M225T. The 189delG, 246insG, 546del13bp and Q212X mutants encode truncated
proteins. COS-1 cells transfected with expression vectors encoding cDNAs
for the mutant StAR proteins which affect the C-terminus, 838delA, A218V
and Q258X, exhibited no steroidogenesis enhancing activity. However, the
M225T mutant retained some steroidogenic activity. The patient with the
M225T mutation had late onset of this disorder and some capacity to secrete
testosterone in response to hCG. These findings suggest: (i) that the Q258X
mutation can be used as a genetic marker for the screening of Japanese for
lipoid CAH, (ii) that the C-terminus of StAR plays an important role in the
protein's activity and (iii) that there are differences in the extent of
functional impairment of the testis and ovaries in lipoid CAH.
相似文献
25.
Telfer JF; Thomson AJ; Cameron IT; Greer IA; Norman JE 《Human reproduction (Oxford, England)》1997,12(10):2306-2312
Superoxide, an agent which attenuates the half-life of nitric oxide, is
metabolized and synthesized by superoxide dismutase (SOD) and xanthine
oxidase, respectively. Over the last few years much work has focused on the
role of nitric oxide in human parturition. The aim of this study was to
determine whether the onset of human parturition is associated with a
change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD),
manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the
uterus. Samples of myometrium, placenta, decidua and fetal membranes were
obtained from women before and after the onset of labour at term.
Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine
oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like
immunoreactivity was detected in syncytiotrophoblast cells, villous stromal
cells and endothelial cells of blood vessels in the placenta. In the
myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial
cells and to some vascular smooth muscle cells. In the fetal membranes we
observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion,
extravillous trophoblast and decidua. There was no difference in SOD enzyme
activity or staining intensity for SOD between different cell types before
and during labour. Xanthine oxidase immunoreactivity was identified in each
of the tissues examined and again there was no difference in immunostaining
in tissues obtained from women delivered before or after the onset of
labour. These results show that the pregnant uterus is capable of both
synthesizing and degrading superoxide and suggest that superoxide dismutase
and xanthine oxidase may play a role in the maintenance of uterine
quiescence during pregnancy, but not in the initiation of parturition.
相似文献
26.
Enhancement of motility by treating spermatozoa with an antioxidant solution (Sperm-Fit) following ejaculation 总被引:1,自引:1,他引:1
Parinaud J; Le Lannou D; Vieitez G; Griveau JF; Milhet P; Richoilley G 《Human reproduction (Oxford, England)》1997,12(11):2434-2436
Oxygen radical generation is known to be detrimental to sperm function,
especially motility, through the lipid peroxidation of the membranes.
Generation of reactive oxygen species can be induced by leukocyte
contamination, sperm centrifugation and the presence of abnormal
spermatozoa with excess residual cytoplasm. This study aims to evaluate the
effect on sperm motility of incubation in an antioxidant-containing
solution, during liquefaction and centrifugation. Thirty semen samples were
each divided into two equal parts: one mixed with Tyrode's solution, the
other with a salt solution containing antioxidants (Sperm- Fit; Ellios
Bio-Media, Paris, France). All the procedures were identical in the two
groups. The ratio of leukocytes to spermatozoa was significantly correlated
with the motility after liquefaction and after a 24 h incubation in routine
in-vitro fertilization (IVF) medium and with the number of motile
spermatozoa recovered after Percoll preparation. Moreover, when this ratio
was > or = 0.2, all motility parameters were lowered. Incubation with
Sperm-Fit allowed a higher percentage of motility after Percoll preparation
when the ratio was > or = 0.2 (48 +/- 5% versus 41 +/- 6% for Sperm-Fit
and Tyrode's solution respectively; P < 0.05) and a greater number of
motile spermatozoa recovered after Percoll preparation, whatever the ratio
(3.2 +/- 1.0 x 10(6) versus 2.4 +/- 0.7 x 10(6) for Sperm-Fit and Tyrode's
solution respectively when ratio > or = 0.2; 18.1 +/- 3.4 x 10(6) versus
14.4 +/- 2.9 x 10(6) for Sperm-Fit and Tyrode's solution respectively when
ratio < 0.2; P < 0.05). These results show that incubation with
antioxidants during liquefaction and centrifugation increases recovery of
motile spermatozoa.
相似文献
27.
Janneke AL van Kempen Henk J Schers Anne Jacobs Sytse U Zuidema Franca Ruikes Sarah HM Robben René JF Melis Marcel GM Olde Rikkert 《The British journal of general practice》2013,63(608):e225-e231
Background
Primary care is increasingly interested in the identification of frailty, as it selects the target population for integrated care. However, instruments for the identification of frailty specifically validated for use in primary care are scarce. This study developed the Easycare Two-step Older persons Screening (Easycare-TOS), which provides a valid, efficient, and pragmatic screening procedure to identify frail older people.Aim
This paper aims to describe the development of the Easycare-TOS and the data from the pilot studies.Design and setting
Observational pilot study in seven academic GP practices in and around Nijmegen, The Netherlands.Method
The Easycare-TOS was developed in a cyclic process with the input of stakeholders. In every cycle, the requirements were first defined, then translated into a prototype that was tested in a pilot study. The Easycare-TOS makes optimal use of prior knowledge of the GP, and the professionals’ appraisal is decisive in the frailty decision, instead of a cut-off score. Further, it considers aspects of frailty, as well as aspects of the care context of the patient.Results
The pilot data have shown that after step 1, two-thirds of the patients do not need further assessment, because they are judged as not frail, based on prior knowledge of the GP. The overall prevalence of frailty in this pilot study is 24%. Most professionals who participated in the pilot studies considered the time investment acceptable and the method to be of added value.Conclusion
The Easycare-TOS instrument meets the predefined efficiency, flexibility, and acceptability requirements for use as an identification instrument for frailty in primary care. 相似文献28.
The magnetic resonance (MR) relaxation rates of protons were compared in the myelinated and nonmyelinated nerves of the garfish. The long, large olfactory nerve of the garfish, as an easily accessible source of nonmyelinated axons, is uniquely suited for such a comparison. The T1 and T2 measurements revealed distinct and consistent differences between nonmyelinated olfactory nerves and myelinated optic and oculomotor nerves. Comparisons between water content, lipid content, and relaxation rates indicated that the differences in MR properties represent complex differences in the distribution and physical environment of the constituent lipid and water protons. 相似文献
29.
Intestinal obstruction proximal to a transition zone without an interposed physical barrier usually indicates Hirschsprung disease. The authors report one case of focal small bowel muscular thinning just distal to a transition zone that produced clinical and radiographic findings that simulated long-segment Hirschsprung disease in a 2-day-old infant. 相似文献
30.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1