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排序方式: 共有1310条查询结果,搜索用时 15 毫秒
51.
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
52.
The objective of this study was to determine whether the proposed Malan radiological sinusitis typing (RST) system facilitated a level of agreement and ease of use comparable with the Lund–Mackay (LM) system for chronic rhinosinusitis. Ten observers (one otolaryngologist and nine radiologists), in two separate centres (regional and tertiary), blinded to all clinical data, used these two systems to independently and randomly score and type 15 sets of scans, recording the time to score each film. Using unweighted kappa scores, both methods facilitated a moderate level of agreement, slightly better with the LM system. The Malan system is more time efficient. Preliminarily, this study shows that the Malan RST system is easy to apply with a comparable level of agreement. The Malan RST system is a focused attempt at classifying disease extent radiologically and correlating it to a surgical approach. It emphasizes that scoring systems are vulnerable and proves to be superior to the LM system as a surgical planning tool. To score sinus disease, a Quality‐of‐Life questionnaire in association with this typing method is more appropriate. 相似文献
53.
Jacqueline Banyard Lere Bao Matthias D Hofer David Zurakowski Kristin A Spivey Adam S Feldman Lloyd M Hutchinson Rainer Kuefer Mark A Rubin Bruce R Zetter 《Clinical cancer research》2007,13(9):2634-2642
PURPOSE: We had previously identified a new transmembrane collagen, type XXIII, in metastatic rat prostate carcinoma cells. The purpose of this study was to determine the expression of collagen XXIII in human prostate cancer and investigate its relationship with disease progression. EXPERIMENTAL DESIGN: We investigated collagen XXIII expression in prostate cancer tissue and did a retrospective analysis of association with prostate-specific antigen (PSA)-defined disease recurrence. The presence of collagen XXIII in prostate cancer patient urine was also assessed before and after prostatectomy. RESULTS: Collagen XXIII protein was detected at very low levels in benign prostate tissue and was significantly increased in prostate cancer. Distant metastases exhibited significantly higher collagen XXIII levels compared with either localized prostate cancer or regional (lymph node) metastases. Patients with high collagen XXIII levels had a 2.8-fold higher risk of PSA failure with median time to failure of 8.1 months, compared with low collagen XXIII patients with a median time to failure of 5 years. Multivariate Cox regression showed that the presence of collagen XXIII was significantly associated with time to PSA recurrence, independent of other clinical variables. Collagen XXIII was also detected in prostate cancer patient urine, with reduced levels after prostatectomy, indicating potential as a noninvasive fluid biomarker. CONCLUSIONS: We present the first report demonstrating increased collagen XXIII expression in prostate cancer tissue. We show that collagen XXIII level is a significant independent predictor of PSA-defined disease recurrence, suggesting a potential role as a molecular biomarker of prostate cancer progression and metastasis. 相似文献
54.
ER Brown KA Charles SA Hoare RL Rye DI Jodrell RE Aird R Vora U Prabhakar M Nakada RE Corringham M DeWitte C Sturgeon D Propper FR Balkwill JF Smyth 《Annals of oncology》2008,19(7):1340-1346
BACKGROUND: Tumour necrosis factor-alpha (TNF-alpha) is an important regulator of the chronic inflammation contributing to tumour progression. Infliximab, an anti-TNF-alpha monoclonal antibody was investigated in this trial of patients with advanced cancer. The primary objectives were to determine the safety profile and biological response of infliximab in a cancer population. Clinical response was a secondary objective. PATIENTS AND METHODS: Forty-one patients received infliximab at 5 mg/kg (n = 21) or 10 mg/kg (n = 20) i.v. at 0 and 2 weeks and then every 4 weeks. Post-treatment samples were measured for changes in plasma and serum TNF-alpha, CCL2, IL-6 and C-reactive protein (CRP). RESULTS: Infliximab was well tolerated with no dose-limiting toxic effects. At both doses of infliximab, neutralisation of serum TNF-alpha was observed after 1 h while plasma CCL2, IL-6 and serum CRP were decreased 24 and 48 h following infliximab administration. Seven patients experienced disease stablisation (range 10-50+ weeks). There was no evidence of disease acceleration in any patient. CONCLUSIONS: Infliximab treatment was safe and well tolerated in patients with advanced cancer. There was evidence of biological activity with baseline TNF-alpha and CCL2 being correlated with infliximab response. 相似文献
55.
KA Bergman JF Meis AM Horrevorts L Monnens 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(9):709-711
Systemic candidiasis with renal involvement is a rare but well-recognized complication during intensive care treatment in very-low-birth-weight infants. We report a term neonate who developed anuria associated with bilateral bezoar formation in the renal pelvis and candidemia. The treatment consisted of placement of a nephrostomy tube in the left kidney, short-term irrigation with amphotericin B and iv, and later, oral administration of fluconazole. 相似文献
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PURPOSE: To provide an understanding of the structure, role, and responsibility of the International Federation of Ophthalmological Societies, the International Council of Ophthalmology, and the International Congress of Ophthalmology. These established entities have recently codified their statutes and regulations and registered them in Zurich, Switzerland. METHODS: The International Council of Ophthalmology, which serves as the executive body of the International Federation of Ophthalmological Societies, used historical operating documents to prepare the statutes and regulations, which were reviewed and adopted by the International Federation of Ophthalmological Societies at the 28th International Congress of Ophthalmology in Amsterdam on June 23, 1998. RESULTS: The statutes and regulations of the International Federation of Ophthalmological Societies, the International Council of Ophthalmology, and the International Congress of Ophthalmology are available to supranational ophthalmological organizations, national ophthalmological societies, other ophthalmological organizations, and individual ophthalmologists. CONCLUSIONS: The statutes and regulations of the International Federation of Ophthalmological Societies, the International Council of Ophthalmology, and the International Congress of Ophthalmology provide a basis for an organizational structure in international ophthalmology. The International Congress of Ophthalmology, first held in 1857, is the longest continuing international meeting in medicine. The International Council of Ophthalmology was established in 1927, and the International Federation of Ophthalmological Societies was formed in 1933. These organizations coordinate the International Congress of Ophthalmology, which convenes with the International Federation of Ophthalmological Societies every 4 years. The International Council, as the executive body, meets annually. The International Council of Ophthalmology has for decades worked to coordinate and facilitate interchange, education, and standards in international ophthalmology. Currently, the International Council of Ophthalmology, working with other international organizations, is creating an international ophthalmology strategic plan, which includes focus on ophthalmic training, continuing education, advocacy for the preservation and restoration of vision, clinical guidelines, and research. 相似文献
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