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Studies of reproductive biology in insects often require quantification of sperm production, transfer or storage. Here, we develop a quantitative real-time PCR-based assay using a Y-specific marker for quantification of sperm from spermathecae of female Queensland fruit fly ('Q-fly'), overcoming constraints typical of traditional sperm quantification methods. The assay enables accurate and reliable quantification of as few as 50 sperms and provides a means to analyse large numbers of samples with flexible timing. The real-time PCR method enables revised understanding of how many sperms are stored by female Q-flies, the distribution of storage between the two spermathecae and the relationship between copula duration and sperm storage. Real-time PCR assays based on Y-specific markers provide an effective solution for sperm quantification in tephritid flies, as well as in other insects and potentially other animals with sperm storage organs. 相似文献
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Jaime L. Clark Carla G. Taylor Peter Zahradka 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2021,31(1):216-226
Background and aimsConsuming pulses (dry beans, dry peas, chickpeas, lentils) over several weeks can improve vascular function and decrease cardiovascular disease risk; however, it is unknown whether pulses can modulate postprandial vascular responses. The objective of this study was to compare different bean varieties (black, navy, pinto, red kidney) and white rice for their acute postprandial effects on vascular and metabolic responses in healthy individuals.Methods and resultsThe study was designed as a single-blinded, randomized crossover trial with a minimum 6 days between consumption of the food articles. Vascular tone (primary endpoint), haemodynamics and serum biochemistry (secondary endpoints) were measured in 8 healthy adults before and at 1, 2, and 6 h after eating ¾ cup of beans or rice. Blood pressure and pulse wave velocity (PWV) were lower at 2 h following red kidney bean and pinto bean consumption compared to rice and navy bean, respectively (p < 0.05). There was greater vasorelaxation 6 h following consumption of darker-coloured beans, as shown by decreased vascular tone: PWV was lower after consuming black bean compared to pinto bean, augmentation pressure was lower after consuming black bean compared to rice and pinto bean, and wave reflection magnitude was lower after consuming red kidney bean and black bean compared to rice, navy bean, and pinto bean (p < 0.05). LDL-cholesterol concentrations were lower 6 h after black bean consumption compared to rice (p < 0.05).ConclusionOverall, red kidney and black beans, the darker-coloured beans, elicited a positive effect on the tensile properties of blood vessels, and this acute response may provide insight for how pulses modify vascular function. 相似文献
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A. D. Kane J. Soar R. A. Armstrong E. Kursumovic M. T. Davies F. C. Oglesby L. Cortes C. Taylor I. K. Moppett S. Agarwal J. Cordingley J. Dorey S. J. Finney G. Kunst D. N. Lucas G. Nickols R. Mouton J. P. Nolan B. Patel V. J. Pappachan F. Plaat B. R. Scholefield J. H. Smith L. Varney T. M. Cook collaborators 《Anaesthesia》2023,78(6):701-711
Detailed contemporary knowledge of the characteristics of the surgical population, national anaesthetic workload, anaesthetic techniques and behaviours are essential to monitor productivity, inform policy and direct research themes. Every 3–4 years, the Royal College of Anaesthetists, as part of its National Audit Projects (NAP), performs a snapshot activity survey in all UK hospitals delivering anaesthesia, collecting patient-level encounter data from all cases under the care of an anaesthetist. During November 2021, as part of NAP7, anaesthetists recorded details of all cases undertaken over 4 days at their site through an online survey capturing anonymous patient characteristics and anaesthetic details. Of 416 hospital sites invited to participate, 352 (85%) completed the activity survey. From these, 24,177 reports were returned, of which 24,172 (99%) were included in the final dataset. The work patterns by day of the week, time of day and surgical specialty were similar to previous NAP activity surveys. However, in non-obstetric patients, between NAP5 (2013) and NAP7 (2021) activity surveys, the estimated median age of patients increased by 2.3 years from median (IQR) of 50.5 (28.4–69.1) to 52.8 (32.1–69.2) years. The median (IQR) BMI increased from 24.9 (21.5–29.5) to 26.7 (22.3–31.7) kg.m–2. The proportion of patients who scored as ASA physical status 1 decreased from 37% in NAP5 to 24% in NAP7. The use of total intravenous anaesthesia increased from 8% of general anaesthesia cases to 26% between NAP5 and NAP7. Some changes may reflect the impact of the COVID-19 pandemic on the anaesthetic population, though patients with confirmed COVID-19 accounted for only 149 (1%) cases. These data show a rising burden of age, obesity and comorbidity in patients requiring anaesthesia care, likely to impact UK peri-operative services significantly. 相似文献
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Taylor R. Valentino Kristin J. Stuempfle Marialice Kern Martin D. Hoffman 《Research in sports medicine (Print)》2016,24(3):197-206
It is advised that individuals should avoid losing >2% of their body mass during exercise in order to prevent hyperthermia. This study sought to assess whether a loss of >2% body mass leads to elevations in core temperature during an ultramarathon. Thirty runners agreed to take part in the study. Body mass and core temperature were measured at the start, at three locations during the race and the finish. Core temperature was not correlated with percent body mass change (p = 0.19) or finish time (p = 0.11). Percent body mass change was directly associated with finish time (r = 0.58, p < 0.01), such that the fastest runners lost the most mass (~3.5–4.0%). It appears that a loss of >3% body mass does not contribute to rises in core temperature. An emphasis on fluid replacement for body mass losses of this magnitude during prolonged exercise is not justified as a preventative measure for heat-related illnesses. 相似文献
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