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91.
Studies on the origin of redox enzymes in seminal plasma and their relationship with results of in-vitro fertilization 总被引:3,自引:0,他引:3
Yeung CH; Cooper TG; De Geyter M; De Geyter C; Rolf C; Kamischke A; Nieschlag E 《Molecular human reproduction》1998,4(9):835-839
Glutathione (GSH), GSH peroxidase (GPX), GSH reductase (GRD), superoxide
dismutase (SOD) and catalase-like enzyme activity were quantified in
seminal plasma from normozoospermic patients, men with known distal ductal
occlusion, proven fathers and male partners of couples receiving in-vitro
fertilization (IVF) treatment for both male and female causes. Glutathione
was non-detectable (< 2.5 microM) in seminal plasma. None of the enzyme
activities per unit volume were lower in semen from vasectomized men,
suggesting that they did not originate substantially from the testis or
epididymis. The strongest relationships between enzyme activities and
accessory gland markers were between zinc and GRD (r = 0.678), SOD (r =
0.602) and GPX (r = 0.548), suggesting a largely prostatic origin of these
enzymes. Only weak relationships between accessory gland markers and
catalase-like activity suggested a multi-glandular source of this enzyme.
There was no relationship between the activity of any of the enzymes in the
IVF patients with their fertilization rates in vitro or the establishment
of pregnancy after IVF. Nor was there any correlation of enzyme activity
with the morphology and percentage of motile spermatozoa in semen or with
the percentage motility of spermatozoa immediately after swim-up or after
overnight incubation. These findings suggest that the protective enzymes in
the seminal plasma are contributed largely by the prostate and little by
the epididymis, and that in most cases of IVF, they have no major influence
on the outcome.
相似文献
92.
Report of an unusual lymphoma arising from parafollicular B-lymphocytes (PBLs) or so-called "monocytoid" lymphocytes 总被引:2,自引:0,他引:2
J B Cousar D L McGinn A D Glick A F List R D Collins 《American journal of clinical pathology》1987,87(1):121-128
A distinctive B-cell has been recognized recently in reactive lymph nodes, especially those of toxoplasmic lymphadenitis. Previously designated as "immature sinus histiocytes" or "monocytoid" cells, these B-lymphocytes proliferate in subcapsular and parenchymal sinuses and the parafollicular area of nodes. The authors now report a 55-year-old male who developed a malignant lymphoma composed of cells with light microscopic, immunologic, and ultrastructural characteristics identical with these newly described B-cells. The term parafollicular B-lymphocytes (PBLs) is recommended herein to emphasize their morphologic and immunologic features. An unusual feature of this PBL lymphoma is the numerous benign-appearing hyperplastic follicles surrounded by the neoplastic infiltrate, mimicking the cytologic appearance and distribution of PBLs seen in toxoplasmic lymphadenitis. The function of these recently recognized B-cells is unknown; their anatomic relationship with hyperplastic follicular centers in reactive states and the lymphoma herein described suggests a role in follicular function. 相似文献
93.
94.
We describe the case of a 68-year-old woman who presented with an acute onset spontaneous vaginal vault rupture and intestinal prolapse through the vagina. Results of a literature survey are presented and the causes of vaginal vault rupture are discussed. 相似文献
95.
This randomized double-blind placebo-controlled study was initiated to analyze the behavior of epididymis, processus vaginalis and testicular descent in cryptorchid boys treated with a low dose (20 g) of a luteinizing hormone-releasing hormone analogue (Buserelin), administered daily, as a nasal spray, for a short period (28 days). Fifty-nine true cryptorchid boys were randomly assigned to 3 groups: buserelin, treatment [22], surgical treatment [18] or placebo control group [19]. The 3 groups of patients were similar before treatment in regard to testicular position, chronological and bone age, height and weight, luteinizing hormone, follicle-stimulating hormone, testosterone, penile size and the volume of the contralateral descended testis. None of the patients had retractile testes. Buserelin significantly induced testicular descent compared to the boys treated with a placebo (P<0.01). A normal epididymis was found more often in boys with successful descent (P<0.003). A closed processus vaginalis was also more frequently observed in the group treated with buserelin than in surgically treated one (P<0.05). In conclusion, buserelin was capable of inducing testicular descent besides provoking further development of the epididymis and closing the processus vaginalis. 相似文献
96.
97.
Cooper TG Hellenkemper B 《国外医学(计划生育.生殖健康分册)》2010,29(3):221-224
本研究的目的是提高用过氧化物酶试验检测精液中的白细胞时所得的圆形细胞数量的精确度。精液样本的圆形细胞浓度在(0.6~6)×10^6/mL之间,降低精液的稀释度,增加被测悬浮液的体积。1+5(1:6)的稀释度适合于测量过氧化物酶活性,并能为细胞检测提供足够清晰的背景。在该稀释度下,测定Neubauer-改良精子计数板两边所有18个网格中的细胞数量,额定细胞浓度为(1.9~3.3)×10^6/mL的10个样本中只有3个样本的圆形细胞数/〉400个。由于更低浓度的精子稀释液不适合测定圆形细胞或其过氧化物酶反应产物,所以无法精确测量(抽样误差5%)参考下限值(1×10^6/mL)。结果表明,正是由于测定精液中的10个样本中圆形细胞很难精确到1×10^6/mL,所以白细胞精液症临界值的确定一直存在诸多分歧。因此需要建立一些统计学上合理的参考限。 相似文献
98.
The paper aims to determine whether the inflammation,a powerful risk factor that has been demonstrated for the development of coronary artery disease,plays a role in no-reflow phenomenon in patients with acute myocardial infarction (AMI) after percutaneous coronary intervention (PCI).Methods We prospectively analyzed 656 patients with AMI after primary PCI.Based on post-PCI angiography data,patients were divided into two groups:the no-reflow group (TIMI=2,n =60) and the reflow group (TIMI=3,n =596).Results Our results showed that the inflammatory factors including leukocyte count (×109/L) (10.90±4.04 vs.9.12±2.98 P =0.002),hs-CRP (5.04±0.71 vs.4.70±0.75 P =0.001) and other factor platelet count (×109/L) (210.96±33.42 vs.196.41±46.06 P =0.033) in no-reflow group are significantly higher than those in reflow group,major adverse cardiac events happened in the patients with no-reflow are higher than in reflow patients no matter in hospital or at the end of follow-up.We also found the left ventricular ejection fraction (LVEF) dramatically decreased (58.65±9.34 vs.51.29±11.38,P<0.001) and left ventricular end-diastolic dimension (LVEDD) significantly increased (49.94±6.75 mm vs.54.66±6.68mm,P<0.001) in no-reflow patients at the end of follow-up.Conclusions Our results suggest that inflammation factors function in no-reflow phenomenon,and no-reflow is a serious complication after primary PCI which predicts poor left ventricular systolic functional recovery and mortality in patients with AMI.(J Geriatr Cardiol 2008;5:217-222) 相似文献
99.
Dopa-responsive dystonia in British patients: new mutations of the GTP- cyclohydrolase I gene and evidence for genetic heterogeneity 总被引:4,自引:0,他引:4
Bandmann O; Nygaard TG; Surtees R; Marsden CD; Wood NW; Harding AE 《Human molecular genetics》1996,5(3):403-406
Dopa-responsive dystonia (DRD) was originally described in a series of
Japanese patients, but is now increasingly recognized in other countries.
Recently the GTP cyclohydrolase I (GTPCH) gene was isolated as the first
causative gene for dopa-responsive dystonia (DRD). Mutations were
identified in three Japanese families with autosomal dominantly inherited
DRD and in one sporadic Japanese patient. Characterisation of the
exon-intron boundaries of this gene has now allowed the analysis of
mutations at the level of genomic DNA. Amplifying all six exons, we
analyzed the GTPCH gene in nine British families with 33 affected family
members and in three sporadic cases and found six new mutations. Only point
mutations were found, causing a stop codon in one family and an amino acid
change in highly conserved regions of the gene in a further four families
and in one sporadic case. None of these mutations were detected more than
once and none of the mutations previously described were found in our
patients. No mutations were identified in four families and in two sporadic
cases.
相似文献
100.
Bioreducible polymer-transfected skeletal myoblasts for VEGF delivery to acutely ischemic myocardium
Implantation of skeletal myoblasts to the heart has been investigated as a means to regenerate and protect the myocardium from damage after myocardial infarction. While several animal studies utilizing skeletal myoblasts have reported positive findings, results from clinical studies have been mixed. In this study we utilize a newly developed bioreducible polymer system to transfect skeletal myoblasts with a plasmid encoding vascular endothelial growth factor (VEGF) prior to implantation into acutely ischemic myocardium. VEGF has been demonstrated to promote revascularization of the myocardium following myocardial infarction. We report that implanting VEGF expressing skeletal myoblasts into acutely ischemic myocardium produces superior results compared to implantation of untransfected skeletal myoblasts. Skeletal myoblasts expressing secreted VEGF were able to restore cardiac function to non-diseased levels as measured by ejection fraction, to limit remodeling of the heart chamber as measured by end systolic and diastolic volumes, and to prevent myocardial wall thinning. Additionally, arteriole and capillary formation, retention of viable cardiomyocytes, and prevention of apoptosis was significantly improved by VEGF expressing skeletal myoblasts compared to untransfected myoblasts. This work demonstrates the feasibility of using bioreducible cationic polymers to create engineered skeletal myoblasts to treat acutely ischemic myocardium. 相似文献