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The effects of arachidonic acid (AA) on binding of [3H]naloxone to the agonist and antagonist configurations of opioid receptors were investigated in rat brain. Equilibrium binding parameters of the agonist and antagonist configurations of the receptors were evaluated from homologue displacement data in the presence or absence of AA. Addition of AA at a concentration of 0.6 mM (1.5 mumole/mg of protein) reduced by 22% and 53% the maximal number of binding sites (Bmax) respectively in the absence or presence of 100 mM NaCl. Binding affinity (KD) was not altered significantly (P < 0.05) either in the presence or absence of 100 mM NaCl and AA. We conclude that AA mediated reduction in [3H]naloxone specific binding was chiefly due to a decrease in the number of binding sites. 相似文献
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Male infertility affects approximately 30% of infertile couples. As spermatozoa mature in the epididymal lumen, their potential for mobility increases, and their protein, lipid and small RNA (sRNA) content changes, whereas capacitation and fertilisation take place in the female reproductive tract. Both of the latter processes are affected by maturation, because impaired maturation causes premature capacitation and fertilization. The epididymis produces a suitable environment for sperm maturation via ion transport, vesicle secretion and protein matrix formation. The microenvironment for sperm maturation varies in three broad segments: the caput, the corpus and the cauda epididymis. Epididymosomes transfer proteins, lipids and sRNAs from the epididymal epithelium to spermatozoa and genetic alterations of epididymal genes can lead to decreased sperm motility, morphological abnormalities of spermatozoa and subfertility. Genetic factors are involved in all aetiological categories in male infertility. However, studies conducted on the genes involved in epididymal functions are limited. The sRNA content of spermatozoa changes during epididymal migration, and these sRNAs play a role in embryo development and epigenetic inheritance. This review aims to clarify the role of the epididymal epithelium in the maturation of spermatozoa in light of the current molecular genomic knowledge. 相似文献
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The use of laparoscopic surgery in peritonitis has increased rapidly. The present study examined the effects of pneumoperitoneum on bacterial clearance. Spraque-Dawley rats were divided into six groups of seven animals. In groups 1 and 4, laparotomy with a midline incision was performed and 10(9) E. coli in a volume of 1 ml inserted into the peritoneal cavity. Groups 2, 3, 5, 6 received an identical quantity of E. coli by intraperitoneal injection. Groups 3 and 6 received carbon dioxide pneumoperitoneum at a constant pressure of 5 mmHg for 60 minutes after intraperitoneal injection of E. coli. In one hour groups; the mean bacterial counts per lung from the E. coli injection with laparotomy group was significantly higher than for the E. coli injection with pneumoperitoneum group (p < 0.05). The mean bacterial counts per kidney in the E. coli injection with laparotomy group was higher compared with the E. coli injection and E. coli injection with pneumoperitoneum groups (p < 0.0001). There was statistically significant difference in quantitative bacteraemia between the E. coli injection with laparotomy group and the E. coli injection or E. coli injection with pneumoperitoneum groups (p < 0.05). In four-hour groups; the mean bacterial counts of lungs and liver-spleen were significantly higher in the E. coli injection with laparotomy group than in the E. coli injection and E. coli injection with pneumoperitoneum groups (p < 0.05 and p < 0.001 respectively). The quantitative bacteria was significantly higher in the E. coli injection with laparotomy group than in the E. coli injection and E. coli injection with pneumoperitoneum groups (p < 0.05). This study demonstrates that pneumoperitoneum impairs the clearance of bacteria from the peritoneal cavity in an experimental model of peritonitis. However, we could not detect the deleterious effects of pneumoperitoneum compared with laparotomy. 相似文献
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M. Melikoglu S. Apaydin V. Hamuryudan S. Yurdakul N. Uygun H. Aki G. Ozbay Dr. H. Yazici 《Clinical rheumatology》1996,15(5):498-500
Summary A patient with end stage renal disease developed ischaemic skin necrosis and digital gangrene. He had diffuse arterial calcification associated with hyperparathyroidism secondary to renal failure. The patient received inappropriate cyclophosphamide therapy as he had been misdiagnosed as having an inflammatory vasculitis. This clinical picture, previously named calciphylaxis should come into the differential diagnosis of systemic vasculitis in a uraemic patient with hyperparathyroidism. 相似文献
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Nihal Aladag Muge Filiz Pinar Topsever Petek Apaydin Suleyman Gorpelioglu 《The European journal of contraception & reproductive health care》2006,11(2):81-88
OBJECTIVES: To determine the differences in and factors related to satisfaction between barrier (male condom) and non-barrier method users. METHODS: A semi-structured questionnaire was used for collecting data for this cross-sectional survey. The questionnaires were completed via one-on-one interviews by the researchers. The study group was selected using stratified random sampling. Exclusion criteria were, being unmarried, pregnant, in postmenopausal status and using traditional methods. A total of 434 currently married women using modern contraceptive methods participated in the study. Contraceptive users were dichotomized into two groups as non-barrier method users and barrier method users. RESULTS: About half of the participants (n = 191, 44%) were barrier method users. Their mean age was 33.7 +/- 7.3 years, 66.6% (n = 131) were well educated and reported significantly less pregnancies, given births, living children and abortions (reproductive history events) than non-barrier users. Barrier method users were significantly more likely to be satisfied with their contraceptive method of choice (OR: 2.4; 95% CI 1.2-5.2). Among barrier method users, deciding the type of the contraceptive method themselves had significant effect on satisfaction.CONCLUSION: In our study, satisfaction was mostly affected by heavy side effects and health risks of the methods resulting in less satisfaction with the contraceptive method among non-barrier method users. Other factors which may influence satisfaction deserve further investigation. 相似文献
8.
Joe Iwanaga Vishram Singh Aiji Ohtsuka Youngil Hwang Hee‐Jin Kim Janusz Mory Kumar Satish Ravi Domenico Ribatti Paul A. Trainor Jos Ramn Saudo Nihal Apaydin Gülgün engül Kurt H. Albertine Jerzy A. Walocha Marios Loukas Fabrice Duparc Friedrich Paulsen Mariano Del Sol Philip Adds Ahmed Hegazy R. Shane Tubbs 《Clinical anatomy (New York, N.Y.)》2021,34(1):2-4
Research within the anatomical sciences often relies on human cadaveric tissues. Without the good will of these donors who allow us to use their bodies to push forward our anatomical knowledge, most human anatomical research would come to a standstill. However, many research papers omit an acknowledgement to the donor cadavers or, as no current standardized versions exist, use language that is extremely varied. To remedy this problem, 20 editors‐in‐chiefs from 17 anatomical journals joined together to put together official recommendations that can be used by authors when acknowledging the donor cadavers used in their studies. The goal of these recommendations is to standardize the writing approach by which donors are acknowledged in anatomical studies that use human cadaveric tissues. Such sections in anatomical papers will not only rightfully thank those who made the donation but might also encourage, motivate, and inspire future individuals to make such gifts for the betterment of the anatomical sciences and patient care. 相似文献
9.
Targeted vessel reconstruction in non‐contrast‐enhanced steady‐state free precession angiography
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Efe Ilicak Suheyla Cetin Elif Bulut Kader Karli Oguz Emine Ulku Saritas Gozde Unal Tolga Çukur 《NMR in biomedicine》2016,29(5):532-544
Image quality in non‐contrast‐enhanced (NCE) angiograms is often limited by scan time constraints. An effective solution is to undersample angiographic acquisitions and to recover vessel images with penalized reconstructions. However, conventional methods leverage penalty terms with uniform spatial weighting, which typically yield insufficient suppression of aliasing interference and suboptimal blood/background contrast. Here we propose a two‐stage strategy where a tractographic segmentation is employed to auto‐extract vasculature maps from undersampled data. These maps are then used to incur spatially adaptive sparsity penalties on vascular and background regions. In vivo steady‐state free precession angiograms were acquired in the hand, lower leg and foot. Compared with regular non‐adaptive compressed sensing (CS) reconstructions (CSlow), the proposed strategy improves blood/background contrast by 71.3 ± 28.9% in the hand (mean ± s.d. across acceleration factors 1–8), 30.6 ± 11.3% in the lower leg and 28.1 ± 7.0% in the foot (signed‐rank test, P < 0.05 at each acceleration). The proposed targeted reconstruction can relax trade‐offs between image contrast, resolution and scan efficiency without compromising vessel depiction. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
10.
Calkavur T Yagdi T Apaydin A Islamoglu F Posacioglu H Durmaz I Ozbaran M 《The Journal of heart valve disease》2002,11(2):263-269
BACKGROUND AND AIM OF THE STUDY: Although over 20,000 Edwards-Duromedics valves were implanted worldwide between 1982 and May 1988, use of the valve was voluntarily suspended by the manufacturer in May 1988 on the basis of reported leaflet escapes. In 1990, a modified version was introduced to the market, the Edwards-Tekna. The study aim was to evaluate the short-term outcome with this revised valve. METHODS: Between 1994 and 1998, 137 patients (67 males, 70 females; mean age 36.3+/-9.1 years) underwent heart valve replacement with the Edwards-Tekna prosthesis. Among these patients, 72 had isolated mitral valve replacement, 59 isolated aortic valve replacement, and six double-valve replacement. RESULTS: Early hospital mortality was 0.72% (n = 1). Follow up was 95% complete (129/136 patients discharged from hospital). Mean follow up was 24.9+/-10.5 months (range: 2 to 48 months); total follow up was 282.9 patient-years (pt-yr). Actuarial freedom from complications at two-year follow up and linearized incidence (%/pt-yr) of these events were: late mortality 87.8+/-8.5% (1.77%/pt-yr); thromboembolism 89.8+/-4.9% (2.12%/pt-yr); anticoagulation-related bleeding 97.8+/-1.5% (0.71%/pt-yr); prosthetic valve endocarditis 99.1+/-0.9% (0.35%/pt-yr); valve-related mortality 98.2+/-1.2% (0.71%/pt-yr); and valve-related morbidity and mortality 85.0+/-5.0% (4.24%/pt-yr). There was no structural valve failure such as leaflet escape in this series. Clinically significant hemolysis was not encountered (mean postoperative plasma LDH level 345+/-124 IU/l). Preoperatively, 69% of patients were in NYHA classes III/IV; at two years postoperatively 90% of survivors were in classes I/II. CONCLUSION: The Edwards-Tekna mechanical valve prosthesis has shown excellent overall clinical performance in the short term, though long-term data are needed to confirm its durability. 相似文献