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71.
本文用生物伯德图分析了血压稳定性。按照经典的控制理论,讨论了生物系统的稳定性,提出了血压控制的数学模型。根据生物特点,建立了生物伯德图的表达式。作为系统稳定性的指标,增益裕量和相位裕量可以用作图法求得,也可以用计算机求解。实验结果与理论分析能很好地符合。 相似文献
72.
心脏病患者血清七种元素含量与血压及生化指标的关系 总被引:31,自引:0,他引:31
我们检测了心脏病患者血清微量元素Zn、Cu、Fe和常量元素K、Na、Ca、Mg的含量,并与血压及生化指标作相关分析。结果发现心脏病患者K和Ca/Mg显著低于对照组,而Na、Mg、Zn、Fe和Na/K、Zn/Cu则显著高于对照组。K、Ca/Mg与血压呈负相关,而Na、Zn、Fe、Zn/Cu和Na/K与血压呈正相关;Fe与红细胞压积(Hct)呈正相关;Zn/Cu与Hct、甘油三酯、极低密度脂蛋白均呈正相关,而与高密度脂蛋白呈负相关。 相似文献
73.
强噪声对大鼠血液粘度血糖及几种酶的影响 总被引:9,自引:0,他引:9
本文检测强噪声刺激12小时大鼠血液流变学九项指标,胆碱酯酶和谷丙转氨酶活力及血糖浓度,与对照组比较,其结果显示:(1)低切粘度,红细胞电泳时间和全血还原粘度明显增高(P<0.05;P<0.05和P<0.01);(2)真性和假性胆碱酯酶活力明显增高(二者均P<0.01);(3)血清谷丙转氨酶活力和血清葡萄糖浓度显著增高(P<0.01和P<0.05)。揭示强噪声作用后机体听觉外系统发生明显变化,长期暴露后必将严重损伤全身性调节功能而引起脏器损害与疾病。 相似文献
74.
M. Estryn-Behar B. Kapitaniak M. C. Paoli E. Peigne A. Masson 《International archives of occupational and environmental health》1992,64(2):131-139
Summary The aim of this study was to evaluate the level of physical capacity in a female hospital population of Paris and its suburbs. A total of 1505 women working in the selected departments filled in a questionnaire concerning their working conditions, life habits and health and also attended a medical examination. The effort test performed consisted in flexing the legs 20 times with the chest held straigt, in 40 s. The heart rates were measured for the first, the second and the third minutes of recovery (first 15 s multiplied by 4). The blood pressure was measured just after the heart rate, for the first and the third minute. Recovery indices have been constituted from the results. The respective weights of anthropometric and sociodemographic risk factors for recovery indices were studied in multiple logistic regression models. The classification enables us to consider about 25%–30% of our population as having a satisfactory physical capacity, about 26%–27% as having an acceptable capacit, and about 24%–27% as having a weak capacity. About 21% of the population presented an excessive pressure reaction and 44% a questionable pressure reaction. Our results concerning the level of physical capacity of the female nursing staff should be taken into account especially in the future planning of work loads and architectural choices, which must avoid excessive physical burdens in relation to this level. An improvement in the level of physical capacity could be envisaged as well. 相似文献
75.
Drinking History Is Related to Persistent Blood Pressure Dysregulation in Postwithdrawal Alcoholics 总被引:1,自引:1,他引:0
Andrea C. King Oscar A. Parsons Nancy C. Bernardy William R. Lovallo 《Alcoholism, clinical and experimental research》1994,18(5):1172-1176
We have previously demonstrated that alcoholics with transitory (< 72 hr) elevations in blood pressure (BP) during withdrawal continue to show residual cardiovascular dysregulation up to 4 weeks of abstinence. The present study replicates and extends these findings. Alcoholic inpatients were divided into three subgroups ( ns = 14) based on BP during the first 72 hr of withdrawal: transitory hypertensives (tHTs; BP > 160/95 mm Hg), transitory borderline hypertensives (tBHs; 140/90 BP < 160/95), and normotensives (NTs; all BPs < 140/90). All patients had normal resting pressures after 72 hr of withdrawal. At 3–4 weeks postadmission, the alcoholics and 14 nonalcoholic controls (CONTs) were tested at rest and during a 5-min handgrip task. The tHTs showed an exaggerated systolic and diastolic BP response to handgrip compared with NTs and CONTs, with tBHs intermediate ( ps < 0.05). Drinking history showed the tHTs had the highest reported level of alcohol consumption and severity of withdrawal symptoms ( ps < 0.05). Regression analyses indicated that consumption of hard liquor was the variable most predictive of admission BPs; further, parental history of hypertension potentiated this relationship for systolic BP. Age and consumption of nicotine and caffeine were not significant predictors of admission BP. The results suggest a persistent cardiovascular dysregulation in alcoholics showing transient hypertensive withdrawal BPs. These alcoholics may be at increased risk for future alcohol-related cardiovascular disorder. 相似文献
76.
M.C. TEREK S. TAMSEL† S. AYGUL L. AKMAN S.V. IRER‡ I.M. ITIL & G. ALPER‡ 《International journal of gynecological cancer》2006,16(1):376-379
The aim of this study is to evaluate the changes in Doppler resistive index (RI) and plasma creatinine and magnesium concentrations after unilateral ureteral obstruction in a rabbit model. Fourteen adult female rabbits were used in this study. In seven rabbits, the left ureter was ligated with silk suture, and the control group was sham operated. Before surgery and on the second and seventh days after surgery, blood samples were obtained to measure plasma creatinine and magnesium concentrations. Doppler RIs of both kidneys were also measured before surgery and on the second and seventh days after the surgical procedure. With regard to magnesium levels, there was a significant within-subjects sessions difference [F(2, 20) = 15.21, P= 0.001] indicating a decrease through sessions. Magnesium concentrations decreased significantly at the postoperative second and seventh days compared to preoperative baseline levels (P= 0.003 and P= 0.001, respectively). Multifactorial analysis of variance was applied for each session separately with laterality, and groups as factors. The Doppler RI and the creatinine level did not show any significant differences or interactions for all sessions (P > 0.05). The decreasing plasma magnesium concentration after surgery may indicate ureteral injury; however, Doppler studies and creatinine levels may not be useful as well. 相似文献
77.
股骨颈骨折后选择性血管造影评价股骨头血液循环 总被引:13,自引:0,他引:13
目的 探讨选择性血管造影检查对评价股骨颈骨折后早期股骨头血液循环损伤及影响因素的价值。方法采用选择性旋股动脉及支持带动脉造影(DSA),对9例2~23天内单侧股骨颈骨折患者血管损伤和血液循环改变进行评价。结果髋关节囊内出血2例,骨内出血4例,下、后支持带动脉损伤和血管移位各3例。患髋牵引时,除外下支持带动脉,其他支持带动脉无显影或仅显示起始部主干,相应股骨头颈部几无灌注成像,静脉显影延迟;髋关节维持伸直内旋位或囊内注入生理盐水后造影,所有支持带动脉无明确显影或仅显示其主干,股骨头颈部无灌注、染色,静脉显影延迟。结论选择性旋股内、外侧动脉DSA技术是一项准确评价股骨颈骨折后股骨头血液循环损伤及影响因素的微创性检查方法;股骨头血液循环受髋关节体位、囊内压和牵引等因素影响;牵引可导致或加重股骨颈骨折后股骨头缺血。 相似文献
78.
原发性高血压和血液流变学异常之间的关系的研究 总被引:3,自引:1,他引:2
目的探讨原发性高血压病和血液流变学异常改变之间的关系。方法对80例高血压病人进行血液流变学观察。结果原发性高血压病组血液流变学多项指标出现异常升高,与正常对照组比较差异有显著性,其主要表现为全血粘度增高,其增高程度和血压升高程度之间呈正相关趋势。其中红细胞压积增高可能是血液粘度增高的重要因素。结论高血压病患者的血液流变学异常和血压增高程度之间有密切相关性。 相似文献
79.
本文对比观察了中西医结合治疗与单纯西药治疗慢性肾炎的临床疗效,结果表明,前者缓解率及总有效率分别为79.8%和92.1%,显著高于对照组(均P<0.01)。治疗组各临床类型及各中医证型的疗效亦均明显高于对照组相对应的各型肾炎(P<0.05~0.01)。治疗组各型肾炎之血液流变学及甲皱微循环改善均较对照组为显著。两组中完全缓解加基本缓解者,该两类检查指标改善极为显著(P<0.05~0.01),而好转及无效者则无明显改善(P>0.05)。提示临床疗效与之密切相关。 相似文献
80.
活血化瘀中药联合血管内皮生长因子基因转移促进股骨头坏死处新生血管形成的实验研究 总被引:5,自引:4,他引:1
目的:观察活血化瘀中药联合血管内皮生长因子(VEGF)基因转移对促进股骨头缺血坏死处新生血管形成情况。方法:日本大耳兔40只,随机分为对照组、模型组、中药组、基因组和综合组。治疗8周后采用免疫组织化学方法观察股骨头滑膜VEGF阳性细胞率及数字减影血管造影股骨头血管数目改变情况。结果:模型组VEGF阳性细胞表达率减低,与对照组、基因组、综合组比较,差异有显著性意义(P<0.01),与中药组比较,有统计学差异(P<0.05),综合组VEGF阳性细胞表达率较高,与中药组及基因组比较,有统计学差异(P<0.05)。血管数目:在A区,各组与模型组比较,均无统计学差异;在B区,各组较模型组血管数目均有增加,对照组、基因组、综合组与模型组比较,有统计学差异(P<0.05)。综合组与基因组比较有统计学差异(P<0.05),中药组虽然血管数目较模型组多,但是无统计学意义。结论:活血化瘀中药及VEGF基因转移均可促进股骨头缺血坏死处局部新生血管形成和侧支循环的建立,尤以活血化瘀中药联合基因疗法效果为好,为临床应用活血化瘀中药联合基因疗法治疗股骨头缺血性坏死提供实验依据。 相似文献