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排序方式: 共有196条查询结果,搜索用时 15 毫秒
81.
Julian Chavarriaga Juan Prada Peter Olejua Hugo López-Ramos Maryori Manjarrez José-Miguel Silva 《Andrologia》2021,53(11):e14212
Erectile dysfunction is a condition associated with increasing age. Patient evaluation and management should follow a comprehensive, stepwise approach. The aim of this article was to report our experience with the complete study for erectile dysfunction, including intracavernous injection rigidity test, biothesiometry and colour duplex Doppler ultrasound. Data were collected and analysed prospectively. The primary end point was to determine whether treatment decision-making was eased by the CompED test. Secondary end points were to establish which clinical variables prior to the study could impact the results of the CompED test, to finally improve patient selection for the study. 187 patients were recruited, 31.2% of the patients had an axial rigidity below 50%, 28.5% had a peak systolic velocity <25 cm/s, 13.2% had an end-diastolic velocity >5cm/s and 27.5% had an abnormal biothesiometry. The factors that best predicted an abnormal result in any of the tests were age >70 years, IIEF domain A < 14 points, and previous radical prostatectomy or radiotherapy. The CompED test stands as a new alternative for the evaluation of patients with erectile dysfunction, being less time consuming, aiding in a more accurate determination of the aetiology and guiding treatment decision-making. 相似文献
82.
83.
Paul LF Tang Ching‐Lung Cheung Pak C Sham Philip McClurg Bob Lee Shut‐Yan Chan David K Smith Julian A Tanner Andrew I Su Kathryn SE Cheah Annie WC Kung You‐Qiang Song 《Journal of bone and mineral research》2009,24(6):1013-1021
BMD is a heritable trait and risk indicator for osteoporosis. In this study, we used a genome‐wide haplotype association mapping (HAM) approach to identify a haplotype block within Cer1 that partitions inbred mice strains into high and low BMD groups. A cohort of 1083 high and low BMD human subjects were studied, and a nonsynonymous SNP (rs3747532) in human CER1 was identified to be associated with increased risk of both low BMD in premenopausal women (OR: 2.2; 95% CI: 1.0–4.6; p < 0.05) and increased risk of vertebral fractures (OR: 1.82, p = 0.025) in the postmenopausal cohort. We also showed that Cer1 is expressed in mouse bone and growth plate by RT‐PCR, immunohistochemistry, and in situ hybridization, consistent with polymorphisms potentially influencing BMD. Our successful identification of an association with CER1 in humans together with our mouse study suggests that CER1 may play a role in the development of bone or its metabolism. Our study highlights the use of publicly available databases for rapidly surveying the genome for quantitative trait loci. 相似文献
84.
Tzovara A Murray MM Bourdaud N Chavarriaga R Millán Jdel R De Lucia M 《NeuroImage》2012,60(4):1959-1969
Decision-making in an uncertain environment is driven by two major needs: exploring the environment to gather information or exploiting acquired knowledge to maximize reward. The neural processes underlying exploratory decision-making have been mainly studied by means of functional magnetic resonance imaging, overlooking any information about the time when decisions are made. Here, we carried out an electroencephalography (EEG) experiment, in order to detect the time when the brain generators responsible for these decisions have been sufficiently activated to lead to the next decision. Our analyses, based on a classification scheme, extract time-unlocked voltage topographies during reward presentation and use them to predict the type of decisions made on the subsequent trial. Classification accuracy, measured as the area under the Receiver Operator's Characteristic curve was on average 0.65 across 7 subjects. Classification accuracy was above chance levels already after 516 ms on average, across subjects. We speculate that decisions were already made before this critical period, as confirmed by a positive correlation with reaction times across subjects. On an individual subject basis, distributed source estimations were performed on the extracted topographies to statistically evaluate the neural correlates of decision-making. For trials leading to exploration, there was significantly higher activity in dorsolateral prefrontal cortex and the right supramarginal gyrus; areas responsible for modulating behavior under risk and deduction. No area was more active during exploitation. We show for the first time the temporal evolution of differential patterns of brain activation in an exploratory decision-making task on a single-trial basis. 相似文献
85.
Objective: To investigate the protamine and protamine mRNA in the epididymal sperm of normal and infertile rats. Methods: Rats were made infertile by adenine treatment. The total nuclear basic protein (TNBP) of epididymal sperm was extracted and analyzed by gel electrophoresis. The total RNA was isolated and the relative amount of protamne mRNA was determined by means of RT-PCR techniques. Results: The content of protamine in the epididymal sperm was much less in the infertile than that in the normal rats. The same results were obtained with protamine mRNA analysis. Conclusion: The relative amount of protamine mRNA in the sperm could reflect the content of sperm protamine. The results may provide a new approach toward the genetic diagnosis for male infertility. 相似文献
86.
The mechanism of effect of high-dose intravenous immunoglobulin (IVIG) therapy in immune cytopenias is incompletely known. One of the leading theories ascribes the short-term effects of IVIG to the competition of infused IVIG for Fc receptors, thereby inhibiting IgG-mediated clearance. Using a system independent of IgG-Fc receptor interactions, we examined another potential mechanism of IVIG action. Guinea pigs were infused with a human IVIG preparation at 600 mg/kg/day for two consecutive days. Parallel groups of animals were treated with the same volume and/or concentration of saline and albumin. Clearance of IgM- sensitized guinea pig erythrocytes, which is wholly complement dependent, was significantly retarded in animals treated with high-dose IVIG. The effect was specific for IVIG, since human albumin (as a second foreign protein) failed to change the clearance of IgM- sensitized guinea pig erythrocytes. Experiments in which IVIG-treated animals were subjected to pre- and posttreatment clearance studies revealed heterogeneity among individual animals in respect to their response to IVIG infusions. Decrease of available plasma complement components did not account for the effect, since both C3 and CH50 values remained unchanged after IVIG treatment, despite rising levels of IVIG in sera of treated animals. The results of in vitro C3 uptake studies and the effect of IVIG on clearance of preopsonized cells suggest that IVIG produces a kinetic depression of C3 uptake and modifies the process of complement fragment deposition on erythrocytes. A generalized effect on mononuclear phagocytes is less likely but cannot be wholly ruled out. These studies establish another potential mechanism of IVIG action and suggest extension of its use to other complement-mediated diseases. 相似文献
87.
Adeno-associated virus (AAV) vectors can move along axonal pathways after brain injection, resulting in transduction of distal brain regions. This can enhance the spread of therapeutic gene transfer and improve treatment of neurogenetic disorders that require global correction. To better understand the underlying cellular mechanisms that drive AAV trafficking in neurons, we investigated the axonal transport of dye-conjugated AAV9, utilizing microfluidic primary neuron cultures that isolate cell bodies from axon termini and permit independent analysis of retrograde and anterograde axonal transport. After entry, AAV was trafficked into nonmotile early and recycling endosomes, exocytic vesicles, and a retrograde-directed late endosome/lysosome compartment. Rab7-positive late endosomes/lysosomes that contained AAV were highly motile, exhibiting faster retrograde velocities and less pausing than Rab7-positive endosomes without virus. Inhibitor experiments indicated that the retrograde transport of AAV within these endosomes is driven by cytoplasmic dynein and requires Rab7 function, whereas anterograde transport of AAV is driven by kinesin-2 and exhibits unusually rapid velocities. Furthermore, increasing AAV9 uptake by neuraminidase treatment significantly enhanced virus transport in both directions. These findings provide novel insights into AAV trafficking within neurons, which should enhance progress toward the utilization of AAV for improved distribution of transgene delivery within the brain. 相似文献
88.
Decreased actin content of lymphocytes from patients with chronic lymphocytic leukemia 总被引:3,自引:0,他引:3
Actin, a major cytoskeletal protein, was quantitated in normal and chronic lymphocytic leukemia lymphocytes. The actin content of normal human blood lymphocytes was 2.2 +/- 0.4 mg/10(9) cells and represented 6.6% +/- 1.8% of the total cellular protein. A significant decrease (p less than 0.001) was noted in chronic lymphocytic leukemia lymphocytes that contained 1.4 +/- 0.3 mg actin/10(9) cells, constituting 4.3% +/- 1.1% of the total protein. Normal T and B cells did not differ in actin content. Reduced actin levels were found in the T as well as in the B lymphocytes of "B-cell" chronic lymphocytic leukemia. The possible importance of the decreased actin level in the anomalous capping response and motility of chronic lymphocytic leukemia lymphocytes is discussed. 相似文献
89.
90.
Distribution of spermidine and spermine in blood from cystic fibrosis patients and control subjects 总被引:1,自引:0,他引:1
Previous studies have shown an abnormality of the spermidine-to- spermine (Spd/Spm) ratio in whole blood of cystic fibrosis homo-and heterozygotes. To investigate Spd and Spm distribution amoung blood components as a possible cause of the abnormality, blood was fractionated using Rabinowitz's glass bead technique and Boyum's Ficoll- Hypaque method. Free (unconjugated) polyamines were extracted with perchloric acid and quantitated on an amino acid analyzer. In controls, mean +/- SEM concentrations in nmoles/10(9) cells of Spd and Spm, respectively, were 1.02 +/- 0.08 and 0.894 +/- 0.28 for erythrocytes; 126 +/- 31 and 357 +/- 105 for lymphocytes; 36 +/- 16 and 240 +/- 33 for granulocytes; and less than 0.5 and less than 0.5 nmoles/ml for plasma. When converted to the concentration in whole blood, it was found that greater than 90% of Spd and over 70% of Spm was associated with erythrocytes. While the higher cellular concentration in leukocytes was not unexpected, the fact that Spd and Spm in whole blood were primarily associated with erythrocytes was a new finding. Comparison with controls revealed that the Spd/Spm ratio in both whole blood and erythrocytes was significantly higher in the group of cystic fibrosis patients. 相似文献