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91.
OBJECTIVE: To assess the ability of Kruger morphology to predict the outcome of the sperm penetration assay (SPA). DESIGN: A retrospective review using univariate and multivariate analysis, t tests, and logistic regression was performed to examine the correlation between Kruger morphology and the optimized zona-free hamster egg sperm penetration assay (O-HESPA). SETTING: University hospital. PATIENT(S): One hundred fifteen private-practice patients who underwent semen analysis, including Kruger morphology and O-HESPA, as part of an infertility evaluation between 1997-2000 were retrospectively reviewed. INTERVENTION(S): Retrospective analysis of the sperm penetration assay. MAIN OUTCOME MEASURE(S): Univariate and multivariate analysis, Student's t test, and logistic regression were performed to analyze Kruger morphology, count, and viability and their relationship to SCI result. RESULT(S): Univariate analysis demonstrated a statistically significant correlation between SCI and sperm count, viability, and Kruger morphology. Multivariate analysis demonstrated statistically significant correlations between SCI and count and viability. There was no correlation between Kruger morphology and SCI. Logistic regression was performed on the SCI results, using count, Kruger morphology, and viability. Sperm count was found to be the only variable that was statistically significant with respect to SCI results. CONCLUSION: This study demonstrated that Kruger morphology assessment cannot be used to predict the results of SCI or replace it in the management of the infertile couple. 相似文献
92.
Ruttner Z Ivanics T Slaaf DW Reneman RS Toth A Ligeti L 《Journal of the Society for Gynecologic Investigation》2002,9(5):294-298
OBJECTIVE: It has been well established that oxytocin (OXT) increases intracellular free calcium ([Ca(2+)](i)) by targeting both intracellular and extracellular stores, but the mechanisms involved in the increase through activation with prostaglandin F(2alpha) (PGF(2alpha)) are still incompletely understood. This study was designed to elucidate the source(s) of increased [Ca(2+)](i) in response to PGF(2alpha) (10(-6) M) or OXT (10(-8) M) administration in the near-term rat myometrium. METHODS: The animals were divided into an in vitro group (n= 8), where the developed tension of uterine strips was assessed, and an in vivo group (n= 5), where a lobe of the uterus with intact innervation and circulation was loaded with the fluorescent indicator Indo-1 AM to assess [Ca(2+)](i). RESULTS: PGF(2alpha) and OXT induced a 30.1% and 35.9%, respectively, increase in developed tension in the potassium chloride-depolarized myometrial strips. Nifedipine reduced the PGF(2alpha) and OXT increased tension by 65.8% and 49.4%, respectively. In vivo, both PGF(2alpha) and OXT increased [Ca(2+)](i) in the potassium chloride-depolarized uterine muscle by 35.7% and 44.6%, respectively, increases similar to the rises in tension in vitro. Nifedipine reduced these effects of PGF(2alpha) and OXT by 45.3% and 39.6%. CONCLUSION: These findings indicate that in near-term myometrium the source of increased [Ca(2+)](i) after administration of PGF(2alpha), similar to OXT, is both extracellular and intracellular. 相似文献
93.
Aging-induced phenotypic changes and oxidative stress impair coronary arteriolar function 总被引:1,自引:0,他引:1
Csiszar A Ungvari Z Edwards JG Kaminski P Wolin MS Koller A Kaley G 《Circulation research》2002,90(11):1159-1166
We aimed to elucidate the possible role of phenotypic alterations and oxidative stress in age-related endothelial dysfunction of coronary arterioles. Arterioles were isolated from the hearts of young adult (Y, 14 weeks) and aged (A, 80 weeks) male Sprague-Dawley rats. For videomicroscopy, pressure-induced tone of Y and A arterioles and their passive diameter did not differ significantly. In A, arterioles L-NAME (a NO synthase blocker)-sensitive flow-induced dilations were significantly impaired (Y: 41+/-8% versus A: 3+/-2%), which could be augmented by superoxide dismutase (SOD) or Tiron (but not L-arginine or the TXA(2) receptor antagonist SQ29,548). For lucigenin chemiluminescence, O(2)(.-) generation was significantly greater in A than Y vessels and could be inhibited with SOD and diphenyliodonium. NADH-driven O(2)(.-) generation was also greater in A vessels. Both endothelial and smooth muscle cells of A vessels produced O(2)(.-) (shown with ethidium bromide fluorescence). For Western blotting, expression of eNOS and COX-1 was decreased in A compared with Y arterioles, whereas expressions of COX-2, Cu/Zn-SOD, Mn-SOD, xanthine oxidase, and the NAD(P)H oxidase subunits p47(phox), p67(phox), Mox-1, and p22(phox) did not differ. Aged arterioles showed an increased expression of iNOS, confined to the endothelium. Decreased eNOS mRNA and increased iNOS mRNA expression in A vessels was shown by quantitative RT-PCR. In vivo formation of peroxynitrite was evidenced by Western blotting, and immunohistochemistry showing increased 3-nitrotyrosine content in A vessels. Thus, aging induces changes in the phenotype of coronary arterioles that could contribute to the development of oxidative stress, which impairs NO-mediated dilations. 相似文献
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95.
Hegele A Heidenreich A Varga Z von Knobloch R Olbert P Kropf J Hofmann R 《Urological research》2003,30(6):363-366
Various tumor markers for transitional cell carcinoma (TCC) of the bladder have been described, but none of them are used in clinical routine. Fibronectin, a glycoprotein, seems to play a very important role in both the progression and invasion of cancer. The aim of this study was to evaluate cellular fibronectin (cFN) in the urine and blood of patients with TCC of the bladder and to determine its possible role as a tumor marker and prognostic factor. Morning urine samples and blood were collected from 20 patients (8 women, 12 men, mean age 69.9 years) before they underwent transurethral resection of bladder tumors (TURB). Twenty patients (10 women, 10 men, mean age 63.4 years) with nonmalignant urological disorders were recruited as the control group. Determination of cFN in plasma and urine was performed by using a newly developed time-resolved fluorescence immunoassay (TRFIA). Patients with nonmalignant diseases had mean cFN plasma levels of 404 ng/ml (range 181-746 ng/ml). Patients with TCC of the bladder showed significantly higher cFN plasma levels of 686 ng/ml (range 274-1999 ng/ml, p<0.05). Subdivided according to the TNM system, muscle-invasive bladder tumors (n=5) demonstrated higher cFN plasma levels (mean 944 ng/ml) than superficial bladder tumors (n=15, mean 463 ng/ml). There were no differences of plasma cFN concentrations concerning tumor grade and also no differences in urine levels between the different groups. We found a significant difference (p<0.04) of cFN plasma levels between patients with TCC of the bladder and the control group. The difference in cFN plasma levels between pTa/pT1 and >or=pT2 tumors indicates a clinically useful potential of this tumor marker for preoperative staging and postoperative follow-up. Our data underline the important but still unclear role of cFN as a tumor marker in TCC, and this will be the focus of future studies. 相似文献
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98.
Combined analysis of DTI and fMRI data reveals a joint maturation of white and grey matter in a fronto-parietal network 总被引:18,自引:0,他引:18
Olesen PJ Nagy Z Westerberg H Klingberg T 《Brain research. Cognitive brain research》2003,18(1):48-57
The aim of this study was to explore whether there are networks of regions where maturation of white matter and changes in brain activity show similar developmental trends during childhood. In a previous study, we showed that during childhood, grey matter activity increases in frontal and parietal regions. We hypothesized that this would be mediated by maturation of white matter. Twenty-three healthy children aged 8-18 years were investigated. Brain activity was measured using the blood oxygen level-dependent (BOLD) contrast with functional magnetic resonance imaging (fMRI) during performance of a working memory (WM) task. White matter microstructure was investigated using diffusion tensor imaging (DTI). Based on the DTI data, we calculated fractional anisotropy (FA), an indicator of myelination and axon thickness. Prior to scanning, WM score was evaluated. WM score correlated independently with FA values and BOLD response in several regions. FA values and BOLD response were extracted for each subject from the peak voxels of these regions. The FA values were used as covariates in an additional BOLD analysis to find brain regions where FA values and BOLD response correlated. Conversely, the BOLD response values were used as covariates in an additional FA analysis. In several cortical and sub-cortical regions, there were positive correlations between maturation of white matter and increased brain activity. Specifically, and consistent with our hypothesis, we found that FA values in fronto-parietal white matter correlated with BOLD response in closely located grey matter in the superior frontal sulcus and inferior parietal lobe, areas that could form a functional network underlying working memory function. 相似文献
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100.