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101.
AIM: To evaluate the guiding effect of high-frequency stimulation (HFS) on renal denervation (RDN), and to compare the similarities and differences of blood pressure changes at the time of electrical stimulation and radiofrequency ablation. METHODS: A total of 6 Kunming dogs were included in this study. Renal artery abnormalities were excluded by angiography. High-frequency stimulation and radiofrequency ablation were performed at the same sites from distal to proximal segments of the renal artery. Invasive blood pressure (BP) was recorded during the whole procedure. The change of the blood pressure was analyzed. HE and Masson staining was adopted to detect the structural changes in the wall of the renal artery and surrounding tissues. The immumohistochemical staining for tyrosine hydroxylase (TH) was used to observe the renal nerve damage after ablation. RESULTS: Electrical stimulation and radiofrequency ablation were delivered in a total of 50 sites. The BP increasing response was induced at 34% sites (n=17), while the rest sites (66%, n=33) had no response. Compared with the baseline, HFS caused the increases in systolic BP of (0.34±3.38), (0.41±3.04), (10.47±5.73), (13.27±3.63), (10.17±1.87) and (0.78±1.87) mmHg in 6 serial 20 s time segments during 120 s of HFS at positive BP response sites. Similarly, the increases in systolic BP by (-0.88±3.44), (-1.64±3.47), (13.17±3.12), (12.82±3.21), (9.50±2.68) and (-6.09±2.21) mmHg were observed during 120 s of ablation procedure at the same sites in 6 serial 20 s time segments. At non-responding sites, HFS and ablation failed to cause a significant increase in systolic BP. The mean area of nerves in the response sites was (0.51±0.28) mm2, whereas that in non-response sites was (0.09±0.06) mm2 (P<0.01). The average absorbance values of TH in renal nerves at ablation and non-ablation sites were 0.031±0.015 and 0.085±0.018 (P<0.01), respectively. CONCLUSION: Renal sympathetic nerves can be effectively mapped by HFS. Radiofrequency ablation guided by HFS is valid to injure sympathetic nerves around renal artery. 相似文献
102.
We describe the culture and stimulation of lymphocytes from the model marsupial, the tammar wallaby (Macropus eugenii). We also describe the capacity of tammar wallaby lymphocytes isolated from blood, spleen and lymph nodes to produce soluble
immunomodulatory factors. Culture conditions were optimized for mitogen-driven stimulation using the plant lectin phytohaemagglutinin
(PHA). Products secreted by stimulated cells were harvested and crudely fractionated before they were added back to freshly
isolated lymphocytes. Using the 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay, both stimulatory
and inhibitory bioactive factors were detected in serum-free supernatants harvested from mitogen-treated peripheral blood
mononuclear cells. This paper describes the capacity of leukocytes of the tammar wallaby to respond to mitogenic stimulation
and to produce soluble, low-molecular-weight bioactive molecules that possess cytokine-like activity. 相似文献
103.
KAZUSHI MIYASHITA ICHIRO AOKI KOUTARO SENO KENJI TAKI & TAKASHI OGISHIMA 《Fisheries Oceanography》1998,6(4):266-271
In this study, the feasibility of identification and abundance estimation of isada krill, Euphausia pacifica , was examined using a two-frequency (38 and 120 kHz) method. The acoustic survey and midwater trawling were conducted off the Sanriku coast, northern part of Honshu, Japan. In one pattern, the SV difference between the two frequencies was large, and in the other, the SV difference was small. These results were interpreted by scattering models, and showed that discrimination between isada krill and walleye pollock was possible. 相似文献
104.
为研究电刺激采精技术能否在甘肃高寒牧区藏系羊繁殖中推广应用,该技术是否对公羊精液品质和采精量有影响,项目课题组在甘肃省天祝县旦马乡进行了牧区藏羊种公羊电刺激采精实验。选择本土选育的欧拉型藏羊种公羊,配种期每日每只采精2次,即:首日(标注为d1)早上采用传统的假阴道采精法采精,下午采用电刺激法采精,次日(标注为d2)早上采用电刺激法采精,下午采用传统的假阴道采精法采精,依次不同采精方法交叉采精,减少误差,连续采精6d,及时检查采精量及精液密度、精子活力等品质。实验结果表明,甘肃天祝牧区藏羊种公羊电刺激采精所得精液量均在0.80 mL~0.96 mL之间,符合藏系羊正常精液量,平均精子活力均在0.80以上,平均精液密度均“中”以上,精液品质符合人工授精精液品质要求,可应用于藏羊繁殖生产实践。 相似文献
105.
106.
KENTARO HONDA ALISTAIR J. HOBDAY RYO KAWABE NAOKI TOJO KO FUJIOKA YOSHIMI TAKAO KAZUSHI MIYASHITA 《Fisheries Oceanography》2010,19(2):151-158
Juvenile southern bluefin tuna (Thunnus maccoyii, SBT) were monitored in nearshore waters off southwest Australia using acoustic tagging and monitoring over five austral summers (2002/2003–2006/2007) to determine patterns in age‐based distribution of SBT. A total of 20–70 receivers were deployed in early December along one to three cross‐shelf transects and at three inshore topographic features (lumps) where SBT are known to occur; and a total of 59–84 juvenile SBT (41–90 cm fork length) were tagged and released each year. After several months, receivers were recovered, and data extracted. In 2002/2003 and 2003/2004, 2‐yr‐old SBT were detected more frequently in nearshore areas than did 1‐yr old fish. Similarly in 2004/2005 and 2006/2007, it was the larger 1‐yr‐old SBT that were detected more frequently at inshore lumps (>85% of detections) while small 1‐yr‐old SBT were detected more widely over the study area. In 2005/2006, although large 1‐yr‐old SBT were still detected more frequently at inshore lumps than small 1‐yr old SBT, the percentage of all detections at lumps was lower at 31.5%, indicating wider distribution of both small and large age‐1 fish. The observed age‐dependent distribution pattern may be enhanced by the distribution of prey, which disperse or concentrate depending on the local oceanography. 相似文献
107.
Intense fishing pressure has led to changes in species composition, demography and the over‐exploitation of many coastal fishes. To restore populations, artificial reefs (ARs) are used with the assumption that new habitat will increase fish productivity. Kelp bass (Paralabrax clathratus), barred sand bass (P. nebulifer) and California sheephead (Semicossyphus pulcher) are three important recreational gamefish species in southern California. Home ranging behaviour, space use and spawning‐related activity of these three species were quantified on a large AR. Kelp bass used the largest amount of area, but space use was similar among species. While no spawning behaviour could be determined for sheephead, kelp bass exhibited two different activity patterns during spawning months and barred sand bass migrated (indicative of spawning). Results of this study indicate that this large AR is providing suitable habitat for these species, and spawning‐related activity could be a sign that this AR is meeting essential life history demands. 相似文献
108.
Mads Christoffersen Jon C. Svendsen Jane W. Behrens Niels Jepsen Mikael van Deurs 《Fisheries Management and Ecology》2019,26(2):172-182
In just two decades, round goby Neogobius melanostomus (Pallas) has dispersed throughout most of the Baltic and the North American Great Lakes. It thrives in shallow sheltered areas, where it is impacting native fauna. In Denmark, researchers, governmental institutions and fishers have joined in an effort to establish a sustainable round goby fishery. To do so, basic information about the movement of round goby is essential, so the movements of 50 round gobies were tracked using acoustic telemetry. The results revealed that activity took place mainly at night and seasonal migrations were common. The most frequent migration behaviour observed was a seaward return migration during winter, which was further confirmed by a snorkel survey. Tracking data also revealed riverine upstream dispersal. The results demonstrate that the round goby can be mapped using telemetry, and it is suggested that fishing for round goby may improve efficiency by targeting seasonal migration corridors. 相似文献
109.
大亚湾核电临近海域中国毛虾声学探测分析 总被引:1,自引:0,他引:1
于2019年1月11―14日在大亚湾核电基地临近海域尝试采用声学探测技术,同时辅以拖网调查与水下视频观测的方法,对该海域中国毛虾(Acetes chinensis)的空间分布特征、定向迁移聚集规律和种群资源评估方法进行了研究分析,以期为大亚湾核电基地典型冷源致灾生物中国毛虾的监测预警与应急防控提供新的思路。调查发现,拖网渔获物中中国毛虾所占比重在99%以上,仅有数量极少的水母和鱼类。19:00―07:00的声学原位观测结果显示,不同时段中国毛虾海里面积反向散射系数(NASC)波动较大(0.56~170.30m~2/nmile~2),整体呈先增后减的变化趋势,最高值出现在22:30―22:40时段。垂直空间分布上,中国毛虾主要集群分布于水深5.2~7.2m的中下层水域,在22:50―00:10期间有明显向底层迁移的趋势。水平空间分布上,中国毛虾生物量密度由湾内至湾口断面逐渐增大。结合不同时段中国毛虾资源动态规律与水下视频观测结果,调查海域中国毛虾很可能在19:00―23:00期间向湾内迁移,23:00之后向湾口迁移。综上分析可知,声学评估方法较传统的渔业调查手段具有生态、高效、时空分辨率高、能提供实时监测数据等诸多优点,更能满足大亚湾核电站冷源生物安全预警与应急防控的现实需求。 相似文献
110.