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61.
Abstract. Objectives. To evaluate lipids and lipoproteins as risk factors for coronary heart disease (CHD) in older men with non-insulin-dependent diabetes (NIDDM) or abnormal glucose tolerance compared with normoglycaemic men. Design. A prospective, population-based cohort study based on the lipoprotein examination (1970–72) of the Honolulu Heart Program. Follow-up was through to December 1988. Setting. Honolulu, Hawaii. Subjects. Japanese-American men, ages 51–72 at baseline: 2042 with 1 h glucose < 12.5 mmol l?1 (normal group); 376 on oral hypoglycaemic agents or with 1 h glucose ≥ 12.5 mmol l?1 after 50 g oral glucose challenge (abnormal glucose tolerance group). None had prevalent coronary heart disease (CHD) or stroke at baseline. Main outcome measures. Incident CHD: definite nonfatal myocardial infarction (MI) or fatal CHD. Results. There were 221 incident cases in the normal group, and 65 in the abnormal glucose tolerance group. Total and high-density lipoprotein (HDL) cholesterol were significant predictors of incident CHD in men with NIDDM or abnormal glucose tolerance after controlling for age, body-mass index, systolic blood pressure, pack-years of cigarettes and alcohol consumption (P < 0.05). Total, low-density lipoprotein (LDL) and very-low-density lipoprotein (VLDL) cholesterol were significant predictors in normal men, and HDL cholesterol was of borderline significance. Conclusions. Abnormal lipids and lipoproteins are significant, independent predictors of CHD in subjects with NIDDM or abnormal glucose tolerance. Attention to lipid and lipoproteins as CHD risk factors should be part of clinical management of these patients. 相似文献
62.
复方天棘胶囊对老龄鼠血气影响的研究 总被引:1,自引:0,他引:1
本研究选用昆明种老龄鼠50只,随机分为正常对照组、阳性对照组和复方天棘胶囊高、中、低剂量组;每组10只。观察灌服复方天棘胶囊溶液对实验性老龄鼠血气的影响。结果表明,老龄鼠灌服2.0、1.0和0.5g/kg体重复方天棘胶囊溶液及5.0g/kg体重红参水煎液10天后,复方天棘胶囊各剂量组均有不同程度的升高动脉血氧分压(PaO_2)和血氧饱和度(SaO_2)的作用;且随剂量的递增,PaO_2和SaO_2明显升高,其中高剂量组升高PaO_2和SaO_2的作用最为明显(P<0.01);红本组SaO_2也有明显升高(P<0.01)。提示复方天棘胶囊具有升高PaO_2和SaO_2的作用。 相似文献
63.
Mario Feola Jan Simoni David Fishman Rue Tran Peter C. Canizaro 《Artificial organs》1989,13(3):209-215
Hemoglobin (Hb) solutions can cause vasoconstriction and activation of intravascular coagulation. Because the endothelium plays a major role in the regulation of vascular tone and hemostasis, a study was conducted of human umbilical vein endothelial cells (EC) incubated with various Hbs. Cell injury was evaluated by electron microscopy and the release of lactic dehydrogenase, H2O2, and procoagulant "tissue factor." Cell reaction was assessed by the measurement of 6-keto-prostaglandin F (PGF)1 alpha (metabolite of prostacyclin) and thromboxane B2 (metabolite of thromboxane A2). Incubation with unmodified bovine hemoglobin for 24 h caused no cell injury and a reaction characterized by 48.4 +/- 8.2% increase in 6-keto-PGF1 alpha production, accompanied by 40.2 +/- 9.4% reduction in thromboxane (Tx)B2 (compared with a control group of EC incubated with saline solution). Incubation with a nonpure Hb solution (Hb plus red blood cell membrane aminophospholipids; a-PLs) caused cell injury with significant release of tissue factor, plus a reaction characterized by 97.5 +/- 12.5% increase in TxB2 production accompanied by 25.3 +/- 3% reduction in 6-keto-PGF1 alpha. A second nonpure Hb [Hb plus bacterial environmental endotoxin (E)] caused cell injury, the release of tissue factor, and increased production of both prostaglandins, with greater release of TxB2 (197 +/- 17%) than of 6-keto-PGF1 alpha (112 +/- 8.3%). These data indicate that the endothelium reacts differently to pure and nonpure hemoglobins. The biocompatibility of Hb solutions, with regard to vasoconstriction and activation of intravascular coagulation, depends on the absence of stromal a-PLs and bacterial E. 相似文献
64.
Effects of different inspiratory concentrations of sevoflurane (fluorometyl-1,1,1,3,3,3,-hexafluoro-2-propylether) on blood pressure, heart rate and efferent activities of cardiac sympathetic, cardiac parasympathetic and renal sympathetic nerves were examined using rats either under the resting condition or during noxious mechanical stimulation of a hindpaw. Under the resting condition, an increase in the inspiratory concentration of sevoflurane from 2.1% to 4.2% gradually caused a decrease in blood pressure and heart rate. With the increase in the sevoflurane concentration, cardiac sympathetic nerve activity decreased, whereas renal sympathetic nerve and cardiac parasympathetic nerve activities did not change significantly. When noxious mechanical stimulation was applied to a hind-paw by pinching, blood pressure and heart rate, renal sympathetic and cardiac sympathetic nerve activities all increased at the 2.1% concentration of sevoflurane. The responses of these parameters were attenuated at the 3.1% concentration of sevoflurane and almost disappeared at the 4.2% concentration. Cardiac parasympathetic nerve activity did not change significantly during the pinching stimulation throughout the 2.1–4.2% concentration increase.(Kurosawa M, Meguro K, Nagayama T et al.: Effects of sevoflurane on autonomic nerve activities controlling cardiovascular functions in rats. J Anesth 3: 109–117, 1989) 相似文献
65.
王小新 《中国健康心理学杂志》2002,10(3):161-162
目的 了解高师学生心理健康现状和父母文化程度对高师学生心理健康水平的影响。方法 对河南省部分高师学生进行问卷调查。结果 河南省大部分高师学生心理健康状况是好的和比较好的;15.13%的高师学生心理健康状况不良,教师、咨询人员和家长应高度重视,密切配合,正确地对他们进行引导和教育。结论 父母文化程度不同对高师学生心理健康水平的影响有差异。但差异不显著。 相似文献
66.
Flow cytometry immunolabeling, tube agglutination tests, and thin-layer chromatography immunostaining with two different anti-A
monoclonal antibodies (anti-A mAb1 and anti-A mAb2) and one anti-B mAb were used to demonstrate differences in expression
of the A and B antigens among erythrocytes from type A and four different type AB cats. Although the flow cytometric patterns
of reactivity and agglutination scores for erythrocytes from types A and B cats detected with the anti-A and anti-B mAbs were
consistent, reactivity among erythrocytes of different type AB cats was variable. By flow cytometric analysis, 99.9% of type
A erythrocytes, no type B erythrocytes, 2.5–4.0% of erythrocytes from type AB cats 1, 3, and 4, and 60.7% of erythrocytes
from type AB cat 2 had detectable A antigen when anti-A mAb1 was used. In contrast, 86.4% of type A erythrocytes, no type
B erythrocytes, 20.2–38.0% of erythrocytes from type AB cats 1, 3, and 4, and 68.5% of erythrocytes from type AB cat 2 had
detectable A antigen when anti-A mAb2 was used. In addition, 86.9% of type B erythrocytes, no type A erythrocytes, 83.1–96.8%
of erythrocytes from type AB cats 1, 3, and 4, and 73.0% of erythrocytes from type AB cat 2 had detectable B antigen when
the anti-B mAb was used. Agglutination scores of type AB cats were comparable to the percent binding on flow cytometry. Thin-layer
chromatography immunostains confirmed differences in the amount of A antigen between erythrocyte glycolipids of type A and
AB cats and those of type AB cats 1 and 2. These results suggest that at least two different phenotypes exist within the feline
AB blood type, which differ in the amount of A antigen expressed on the erythrocyte surface. 相似文献
67.
To investigate the age-dependent functional importance of cholinergic neocortical inputs, and to explore whether cortical cholinergic denervation in aged animals might better model the cerebral metabolic changes of Alzheimer's disease, the effects of unilateral ablation of the nucleus basalis magnocellularis (NBM) on cerebral glucose metabolism were studied in young and aged rats. Regional cerebral metabolic rates for glucose (rCMRglc) were determined, using the [14C]deoxyglucose method, in 48 brain regions of 3- and 24-month old Fischer-344 rats at 3, 7, 14 and 28 days after stereotaxic injection of ibotenate into the right NBM, and in sham-operated animals at 3 and 14 days later. For both ages the peak effect of unilateral NBM ablation occurred 3 days later: in young rats, rCMRglc was significantly reduced (compared to the contralateral side) in all 24 anterior cortical areas examined (mean decline 20%), whereas in aged animals, only 9 of 24 areas showed a significant decline in glucose utilization, and the magnitude of rCMRglc reduction (9%) was smaller. Near complete recovery of rCMRglc occurred by 7 days in young and old rats. We conclude that the basalocortical cholinergic projection plays a smaller role in neocortical function of aged rats, possibly because its tonic activity is reduced. Both young and aged rats undergo cortical metabolic normalization after unilateral NBM ablation; hence the NBM-lesioned aged rat is not a better model of the progressive decline in rCMRglc that occurs in Alzheimer's disease. 相似文献
68.
Wie lange ergeben aufbewahrte Blut- und Knochenmarksausstriche zuverlässige zytochemische Färbungen?
Summary We tested how long unstained and unfixed films of blood and aspirated bone marrow could be kept before special cytochemical staining. To exclude influences other than time on the outcome of the reactions, all the material was taken from hematologically normal persons. A simple score was used to evaluate the results. These may be summarized as follows: in most cells Naphthol-AS-acetate-esterase first shows a progressive decline in reactivity after a delay of 6 weeks, the reaction becoming very weak after 10±1 weeks. This does not hold for monocytes, megakaryocytes and platelets, which maintain reactivity (and susceptibility to NaF) for more than three months. With PAS staining, a slight decrease in reactivity after 8±2 weeks could be observed, whereas all other stainings tested (POX, Sudan black B and Naphthol-AS-D-esterase) were unaffected even by a delay of up to 16 weeks. 相似文献
69.
N. A. T. Lusamvuku P. Aubineau R. Sercombe 《Medical & biological engineering & computing》1980,18(5):643-649
A new method is described for simultaneous measurements of electrical and mechanical activity in an intact segment of a small
artery (outside diameter 0·3–0·5 mm). A 7–9 mm segment of rabbit middle-cerebral artery was ligated on a Teflon tube connected
to a perfusion circuit. The presence of a plug in the tube, flanked by two orifices, forced the physiological solution to
flow in the annular space between the tube and the artery wall. Physiological pressures could thus be attained at low rates
of flow, and the pressure, measured upstream, was significantly modifed by the slightest constriction or dilatation of the
vascular segment. Electrical recording with glass microelectrodes was performed on a short immobilised portion of the artery.
The artery and tube were bathed in a physiological solution at 38°C, but perfusing and incubating solutions did not mix. Spontaneous
electrical and mechanical activity of middle cerebral arteries is described, together with modifications induced by vasoactive
agents. 相似文献
70.
Summary The effects of hyperthermia on blood flow and oxygen consumption
of the tongue were investigated in anesthetized dogs. For comparison, blood flow through the skin and deep muscle of the hind leg was also measured in some animals. Increasing blood temperature revealed a biphasic response of lingual blood flow. At 41°C blood temperature respiratory frequency was twice that of control and there was a reduction of lingual blood flow, while resistance of the lingual bed was increased significantly. The arterio-venous oxygen difference (AVDO2) of lingual blood was markedly increased at this level and the
of the tongue was like-wise significantly greater than control. At 41.9°C, the steep increase of respiratory frequency was accompanied by a marked fall in lingual resistance as evidenced by a four-fold increase of lingual blood flow. The systemic AVDO2 rose at this temperature, while the lingual AVDO2 fell dramatically. There was no further increase of lingual
. At both temperature levels the blood flow through the skin did not change substantially, while the deep muscle blood flow slightly increased. The mean arterial pressure showed a progressive fall during hyperthermia. It is assumed that the decrease of lingual blood flow at elevated blood temperature without panting is due to a redistribution of cardiac output to areas other than the tongue. The increase of lingual blood flow without an additional increase of lingual
during panting may be explained solely as a mechanism for heat dissipation. The fact that the decrease of lingual resistance was demonstrated in immobilized animals concomitant with high frequency phrenic burst activity suggests that the decrease of lingual resistance and panting may be induced by a common central integrating mechanism. 相似文献