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991.
《Clinical and experimental hypertension (New York, N.Y. : 1993)》2013,35(6):397-401
We aimed to determine the prevalence and risk factors of retinopathy in hypertensive outpatients. Demographic data, accompanying diseases, anthropometric measurements, and blood and urine biochemistry of 655 hypertensive patients were evaluated. Hypertensive retinopathy rate was 66.3% (grade 1, 33.6%; grade 2, 32.7%). Age, duration of hypertension, and systolic blood pressure levels were significant risk factors for retinopathy (P = .048, P = .035, and P = .012, respectively). Any correlations between retinopathy and gender, body mass index, biochemistry, and associated diseases were not found. This study shows that the degree and duration of hypertension increases the incidence of retinopathy. Low-grade retinopathy seems not to be associated with other cardiovascular risks. 相似文献
992.
M.R. Jones A. Huibonhoa 《Clinical and experimental hypertension (New York, N.Y. : 1993)》2013,35(5):801-810
ABSTRACTEpidemiological studies in man suggest that blood pressures tend to be higher in persons with low calcium (Ca) intakes. Previous studies in normal rats have shown that severe Ca restriction raises blood pressure. The chronic effect of moderate Ca restriction is not known. We evaluated the effect upon systolic blood pressure of rearing young Wistar rats on a diet marginally adequate in Ca. Male weanling Wistar rats (8 rats per group) were placed on one of four diets containing 0.5% Ca (control diet), 0.4% Ca, 0.3% Ca, or 0.2% Ca. The three experimental diets were made up by replacing CaHPO4 in the salt mix with (NH4)H2PO4. Content of PO4 and electrolytes other than Ca was the same for all 4 diets. Sodium (Na) content was 0.1%. Diets were fed for 19 weeks. Rats did not grow normally on the 0.2% Ca diet, but growth was normal on the other three diets. There was no overall statistically significant effect of diet upon systolic pressure. During the first nine weeks of study there were no significant differences between groups and no consistent trends. During the last seven weeks, however, there was a consistent trend toward higher systolic pressures as Ca intake decreased. The mean change in blood pressure during the last five weeks of study from the baseline value at 4 weeks of age was significantly greater in rats consuming 0.2% Ca and tended to be greater in rats consuming 0.3 and 0.4% Ca than in controls. On several occasions, group mean systolic pressures were significantly greater in rats on the experimental diets than in controls. Systolic pressures for individual rats, averaged over the last seven blood pressure measurements, varied over a wider range in the experimental groups than in rats eating the control diet, and the distribution in the experimental groups was shifted toward higher systolic pressures. The results suggest that rearing normal rats on a diet marginally adequate in Ca may lead to a modest elevation in the blood pressures of some, but not all rats. The effect, however, is of much smaller magnitude than that observed with severe Ca restriction. 相似文献
993.
目的探讨双水平无创正压通气在重症心理衰竭患者的护理.方法选择50例重症心力衰竭患者分为对照组和治疗组,对照组在常规治疗的基础上使用鼻导管吸氧,治疗组在常规治疗的基础上使用双水平无创正压通气治疗,观察两组患者治疗前后的临床症状.结果治疗组的疗效明显优于对照组,各指标的恢复都比较迅速.结论双水平无创正压通气是治疗重症心力心衰竭比较可靠、安全、方便、患者容易接受的治疗方法,疗效显著. 相似文献
994.
《Gait & posture》2017
The present study evaluated the measurement of head movements as a valid method for postural emotional studies using the comparison of simultaneous recording of center of pressure (COP) sway as criterion. Thirty female students viewed a set of 12 pleasant, 12 unpleasant and 12 neutral pictures from the International Affective Picture System, repeated twice, using a block presentation procedure while standing on a force platform (AMTI AccuSway). Head movements were recorded using a webcam (©KPC139E) located in the ceiling in line with the force platform and a light-emitting diode (LED) placed on the top of the head. Open source software (CvMob 3.1) was used to process the data. High indices of correlation and coherence between head and COP sway were observed. In addition, pleasant pictures, compared with unpleasant pictures, elicited greater body sway in the anterior-posterior axis, suggesting an approach response to appetitive stimuli. Thus, the measurement of head movement can be an alternative or complementary method to recording COP for studying human postural changes. 相似文献
995.
996.
目的 讨论机械通气患者气管插管导管、气管切开套管的套囊压力和注气量是否合适,提供正确给套囊注气的科学依据.方法 对35例气管插管、气管切开进行机械通气患者的气管套管套囊压力和注气量的实际值和理想值进行准确测量.结果 65%的患者气管套管套囊实际压力和注气量过高,大于理想值.其中套囊实际注气量大于理想注气量2~4ml,套囊压力超过理想压力2~26 cm H2O.结论 临床上大部分气管套管套囊压力和注气量偏高,因此,应对人工气道患者采用专用套囊测压仪指导套囊注气量及控制囊内压,最大限度地避免气道黏膜的损伤. 相似文献
997.
《Sport》2013,29(3):166-171
The European approach of preparticipation screening to prevent sudden cardiac deaths in sports consists of anamnesis, physical examination and ECG. The knowledge of training-related ECG alterations reduces false-positive results. In high performance sports in Germany and some other countries, an exercise ECG is additionally performed. The implementation of the exercise ECG is generally recommended for athletes older than 35 years. Under laboratory conditions, ECG at rest and during exercise can be involved in the performance diagnostics. Measurements of lactate and respiratory parameters during bicycle and treadmill ergometry can be combined with ECG. 相似文献
998.
目的研究酒精摄入对大鼠血压、肝脏结构及学习记忆的影响。方法成年雄性SD大鼠随机分为酒精组与对照组。酒精组给予50%酒精1 ml/(100g bw.d),每天分两次灌胃,对照组给予等量生理盐水灌胃。两组均于灌胃6w后Morris水迷宫观察大鼠学习记忆的改变、颈总动脉插管观察血压,HE染色观察心肌细胞、肝细胞、海马结构的变化。结果⑴与对照组大鼠相比,酒精组大鼠平均逃避潜伏期时间及搜索距离延长(P<0.05);撤离平台后120s内穿过原平台象限内游泳的时间及原平台象限游泳距离占总距离的百分比减小(P<0.05)。⑵两组大鼠血压比较无显著性差异。⑶光镜下观察:与对照组比较酒精组大鼠心肌纤维及海马结构未见明显不同;酒精组大鼠肝细胞有明显的脂肪变性。结论酒精摄入使大鼠学习记忆能力下降、大鼠肝细胞脂肪变性,其对血压的影响还有待进一步研究。 相似文献
999.
《Gait & posture》2021
BackgroundHallux valgus orthoses are available in a wide range of designs and materials, but the effects of their design on functional performance have not been fully investigated.Research questionThis present study aims to comprehensively analyze the immediate effects of soft and semi-rigid hallux valgus orthoses on balance, plantar pressure, hallux valgus angle, and subjective sensations.MethodsSixteen female subjects have participated in the study, including 10 subjects with healthy feet and 6 with hallux valgus. Three conditions are tested, including in the barefoot and using two types of commercially available hallux valgus orthoses. The subjects participate in static and dynamic (walking) tests with the use of the Novel Pedar® system. The peak pressure values in the hallux, lateral toes, first metatarsophalangeal joint, 2-4th metatarsal heads, 5th metatarsal head, medial midfoot, lateral midfoot and rearfoot in the various foot conditions are examined and compared. The hallux valgus angle of each subject is measured based on their footprint. Their subjective feelings towards the orthoses are also evaluated. A repeated-measures analysis of variance, and independent-sample t-test are performed.ResultsThe correction of the hallux valgus angle is statistically significant when the subjects with hallux valgus use the orthoses. In comparing the two types of orthoses, the use of the orthosis made of soft materials results in correction in the hallux valgus angle and higher wear comfort, and lower plantar pressure in hallux area.SignificanceThe results provide insights into the design of hallux valgus orthoses, thus offering practical reference for the selection of hallux valgus orthosis with compromise between functional performance and wear comfort. 相似文献
1000.