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31.
OLAV STOKLAND J
RGEN THORVALDSON ARNFINN ILEBEKK FREDRIK KIIL 《Acta physiologica (Oxford, England)》1982,115(4):455-465
The mechanism of increased preload and its contribution to the rise in blood pressure during intravenous angiotensin infusion were studied in anesthetized dogs. In open-chest dogs angiotensin increased mean aortic blood pressure by 58±12 mmHg. Left ventricular end-diastolic dimension, measured as myocardial chord length (MCL) by ultrasonic technique, increased by 7±1 %. By inflating a balloon in the inferior vena cava, end-diastolic MCL was reduced to control value and the rise in mean aortic blood pressure was almost halved to 32±10 mmHg above control value. A similar preload effect was recorded in closed-chest dogs using end-diastolic left ventricular pressure as an estimate of left ventricular volume. During angiotensin infusion to the upper body only, end-diastolic MCL did not increase. When redistribution of the splanchnic blood volume was prevented, the effect of angiotensin on end-diastolic MCL was reduced to 1/3. Angiotensin reduced liver but not splenic dimension measured by ultrasonic technique. We conclude that about half of the rise in blood pressure during angiotensin infusion is due to increased end-diastolic volume caused by blood redistribution. About 2/3 of this increase in preload is due to redistribution from the splanchnic bed, mainly from the liver. 相似文献
32.
前列腺增生症趋于年轻化的探讨 总被引:1,自引:0,他引:1
目的:探讨不同年龄组前列腺增生症的检出率及原因,以达到早发现,早预防,早治疗的目的.方法:应用Acuson 128xp超声显像仪诊断前列腺增生症.结果:前列腺增生症检出率:35岁~39岁纽1053例,检出8例(0.76%);40岁~44岁组1550例,检出30例(1.68%);45岁~49岁组2855例,检出486例(17.0%);50岁~54岁组2784例,检出715例(25.7%);55岁~59岁2924例,检出1231例(37.5%);60岁~64岁组2450例,检出1521例(62.1%);65岁~69岁组1241例,检出826例(66.6%);70岁~74岁组1118例,检出711例(63.6%);≥75岁组588例,检出293例(49.8%).结论:前列腺增生症并非老年人特有疾病,似有年轻化趋势. 相似文献
33.
Various techniques are used to collect specimens from the nasal mucosa for morphologic and biochemical analysis. The purpose of this study was to devise a method that overcomes some of the disadvantages (e.g., invasive procedure, samples not suitable for cytologic and biochemical analysis, lack of standardization, and poor reproducibility) of these techniques. The new method requires subjects, with neck extended, to inhale an ultrasonic nebulization of a hypertonic (3% NaCl) solution (UNHS) for 5 min. They then blow their nose into a Petri dish, one nostril at a time with the other one blocked. The secretions are dispersed with 0.1% dithiothreitol in phosphate buffer solution for 20 min. Total cell count (TCC) is evaluated, and the cellular suspension is divided into two aliquots: one is centrifuged and the supernatants are collected for eosinophil cationic protein (ECP) measurements; the other is cytocentrifuged and the slides, stained with Diff-Quik, are used for differential cell count. The results obtained with the UNHS and nasal lavage (NL) methods were compared. Eleven nonatopic healthy subjects and 19 allergic rhinitic patients were studied. Total cell count (×105 ) was significantly higher with UNHS than with NL (13.0±12.3 vs 1.911.6; P<0.0]) The differential cell count was similar with the two procedures. ECP levels (μg/l) were higher with UNHS than with NL (39.1+38.2 V.S 16.7±41.2; P<0.01). For evaluation of reproducibility, four healthy and six rhinitic subjects underwent UNHS on two occasions within 5 days, and the results of two samples (sample 1 vs sample 2) were analyzed. Reproducibility was good as to TCC, differential cell count, and ECP 相似文献
34.
本文介绍了盲人智能探路手杖的研究.该系统由单片机控制,采用两只超声波传感器的探测模式,对盲人行进路上的路况进行探测和分析,并针对不同的路况发出相应的提示信息,以达到辅助盲人安全行走的目的. 相似文献
35.
The development of emotional behavior is dependent on the early experiences of the infant and the quality of maternal care. In these experiments, the effects of social isolation during the preweaning period on both pup behavior and maternal responsivity were examined. In the first study, the number of ultrasonic vocalizations (USVs) emitted after brief maternal separation was measured in neonatal rats with differing histories of social isolation. The social isolation procedure consisted of 5 days of daily separation from the dam and littermates for either 3 or 6 hr. At both ages tested, socially isolated pups vocalized significantly less than control pups. In the second study, the effects of prior isolation either daily for 5 previous days (Chronic Isolation) or for 4 hr prior to testing (Acute Isolation) were examined in a T-maze choice test. Pup vocalizations in the presence of the dam and dams' maternal behavior were assessed. When the dam was confined to the start box or during the maternal free access period, both Chronic and Acute Isolates vocalized less than pups that had never left the home nest. Dams spent more time with and licked and groomed more frequently and for a longer time both Chronic and Acute Isolates compared to pups that had always been with dams in the home nest. These results suggest that early isolation experience can alter subsequent responses to separation stress in neonatal rats and that maternal behavior is sensitive to the prior experiences of offspring. 相似文献
36.
目的探讨超声诊断输尿管下段息肉的临床应用价值。方法对12例经输尿管镜或膀胱镜检查、病理检查证实为输尿管下段息肉(其中男性8例,女性4例,年龄17~60岁,平均年龄32.6岁;病程1个月~4年。左侧9例,右侧3例,合并输尿管结石4例,膀胱结石2例,肾结石1例,息肉自输尿管口部分脱入膀胱4例,随输尿管喷尿节律性脱入膀胱2例)的患者超声及临床资料进行回顾分析。结果超声对输尿管下段息肉的诊断符合率为58.3%(7/12)。误诊为输尿管癌3例,膀胱肿瘤2例,误诊率为41.7%(5/12)。其中合并输尿管结石4例,膀胱结石2例,肾结石1例。病理诊断为炎性增生性息肉9例,纤维性息肉3例。结论超声是输尿管下段息肉的首选筛查方法,对合并阴性结石、逆行造影困难、碘过敏者更具有价值。 相似文献
37.
When isolated from their dams and littermates, rat pups emit ultrasonic vocalizations to elicit attention and retrieval from their dams. This study examined the effects of perinatal alcohol exposure on ultrasonic vocalizations and maternal-infant interactions. Alcohol was administered throughout gestation to the dams and during the early postnatal period to the pups. Control groups consisted of a nontreated control and an intubated, pair-fed control. Ultrasonic vocalizations were measured on postnatal day (PD) 5 under varying conditions of isolation. Maternal behaviors were examined on PD2, 4, 6, 8, and 10. Maternal behaviors were not significantly affected by prior alcohol administration to either the dams or the pups. However, ethanol-exposed rat pups vocalized more on PD5 than controls regardless of condition. The heightened vocalization response of the ethanol-exposed pups might be an underlying factor in the persistent effects of perinatal ethanol exposure on social behavior. 相似文献
38.
目的:通过超声的引导,对肾囊肿采取精确定位穿刺治疗,从而使肾囊肿的治疗更为简便有效。方法:从1995年以来的肾囊肿患者中选取12例单纯性肾囊肿患者,在穿刺探头引导下,对肾囊肿进行穿刺注射无水乙醇治疗,并在术后3-12个月进行随访。结果:治疗后3个月治愈率41.7%,6个月66.7%,12个月治愈率83.3%,有效率100%,无并发症发生,结论:超声引导穿刺治疗肾囊肿方法简便,安全可靠,痛苦小,治愈率高,值得向广大基层医院推广。 相似文献
39.
目的 了解胎儿脐带绕颈时对胎儿安危及窘迫和缺氧的影响程度。方法 采用日本Aloka-630型超声诊断仪,孕妇孕周为28-42周。结果 二维超声诊断胎儿脐带绕颈136例,经分娩证实129例。符合率94.85%。结论 二维超声诊断与分娩后证实比较,超声是诊断脐带绕颈的可靠方法之一。为分娩方式提供依据。 相似文献
40.
目的 以茶皂素为天然乳化剂制备黄芩苷纳米乳(baicalin nanoemulsion,Bai-NE),并探究其对C57BL/6小鼠毛发生长的促进作用。方法 采用超声乳化法制备Bai-NE,利用单因素实验法对Bai-NE的处方和制备工艺进行优化,并对最优处方和工艺制备的Bai-NE进行理化性质和稳定性考察。以C57BL/6小鼠为研究对象,评价Bai-NE对毛发生长的促进作用。结果 Bai-NE的最佳处方为茶皂素用量为0.5%,油相用量为5%,最佳制备工艺为超声功率180W,超声时间10min,超声次数1次。制得的Bai-NE为O/W型乳液,外观均一,平均粒径为(225.1±0.6)nm,多分散指数(polydispersity index,PDI)为0.082±0.031,载药量为1.10mg/g,pH值为7.25±0.20。稳定性结果显示,Bai-NE具有良好的离心稳定性和储存稳定性。Bai-NE能显著促进C57BL/6小鼠的毛发生长。结论 茶皂素可作为一种潜在的天然乳化剂用于Bai-NE的制备,制备的Bai-NE对C57BL/6小鼠的毛发生长有促进作用。 相似文献