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排序方式: 共有3387条查询结果,搜索用时 46 毫秒
91.
R Slutsky D Gordon J Karliner A Battler S Walaski J Verba M Pfisterer K Peterson W Ashburn 《The American journal of cardiology》1979,44(3):459-465
To identify abnormal left ventricular function without exercise stress in patients with coronary artery disease first-pass radionuclide angiograms were analyzed in 32 normal subjects (Group I); 31 patients with coronary disease and normal contrast ventriculograms (Group II); and 17 patients with coronary disease and depressed left ventricular function (Group III). Total ejection fraction (EF) was computed with standard angiographic methods and from each time-activity curve. During the first third of systole, ejection fraction was determined manually by averaging three to five beats and the value compared with that obtained with contrast ventriculography: (Formula: see text). Both total radionuclide ejection fraction (r = 0.95) and first-third ejection fraction (r = 0.91) correlated well with angiography. Intraobserver and interobserver variation was small, averaging 0.02 +/- 0.02 (range 0 to 0.05). The radionuclide first-third ejection fraction was 0.25 or greater in normal subjects and less than 0.25 in 29 of 31 patients (94 percent) in Group II and in all patients in Group III. It is concluded that the first-third ejection fraction obtained with first pass angiography identifies subtle abnormalities of left ventricular function at rest in more than 90 percent of patients with coronary disease that may not be recognized by total ejection fraction alone. 相似文献
92.
93.
Alteration of type A behavior and reduction in cardiac recurrences in postmyocardial infarction patients 总被引:3,自引:0,他引:3
M Friedman C E Thoresen J J Gill L H Powell D Ulmer L Thompson V A Price D D Rabin W S Breall T Dixon 《American heart journal》1984,108(2):237-248
Eight hundred sixty-two postmyocardial infarction patients volunteered to be randomly selected and enrolled into: (1) a control section of 270 patients, who received group cardiologic counseling; and (2) an experimental section of 592 patients, who received group type A behavior counseling in addition to group cardiologic counseling. Reduction in type A behavior at the end of 3 years was observed in 43.8% of the 592 participants, who initially were enrolled to receive group cardiologic and type A behavioral counseling. This degree of behavioral reduction was significantly greater than that observed in participants who initially were enrolled to receive only group cardiologic counseling. The 3-year cumulative cardiac recurrence rate was 7.2% in participants who initially were enrolled to receive group cardiologic and type A behavioral counseling. This was significantly less (p less than 0.005) than that (13%) observed in participants who initially were enrolled to receive only cardiologic counseling. This difference in recurrence rates was due to a lesser incidence of nonfatal infarctions in the patients who had been enrolled in the section receiving type A behavioral as well as cardiologic counseling. These data suggest that type A behavior can be altered in a sizable fraction of postinfarction patients and that such alteration is associated with a significantly reduced rate of nonfatal myocardial infarctions. 相似文献
94.
Charles R McKay Kanu Chatterjee Thomas A Ports Anne N Holly William W Parmley 《American heart journal》1982,104(3):575-580
The hemodynamic response to minoxidil, an orally active, potent vasodilator, was evaluated in 11 patients with severe chronic congestive heart fallure (CHF). The hemodynamic response was determined following single doses of 10, 15, 20, 25, and 30 mg of minoxidil. The hemodynamic response was characterized by marked increases in cardiac index (+63%) and stroke volume index (+52%) and by decrease in systemic vascular resistance (?38%). There was also a slight decrease in pulmonary capillary wedge pressure from an average of 24 ± 8 to 21 ± 7 mm hg. Although the average mean arterial pressure remained unchanged, one patient developed significant hypotension. Chronic minoxidil therapy (eight patients) was associated with fluid retention and weight gain. In four patients in whom fluid retention could be minimized with larger doses of diuretics, a sustained clinical and hemodynamic improvement was observed. These findings suggest that minoxidil has the potential to improve cardiac function and may be useful in chronic vasodilator therapy of CHF, provided fluid retention can be controlled. 相似文献
95.
K O Raivio A Becker L J Meyer M L Greene G Nuki J E Seegmiller 《Metabolism: clinical and experimental》1975,24(7):861-869
In order to clarify the mechanism of hyperuricemia and hyperuricosuria resulting from rapid infusion of fructose in man, the effects of an intravenous infusion of 125-200 g of fructose given over 3-4 hr on the rate of purine synthesis de novo was measured in one individual with osteoarthritis and four patients with gout. The incorporation of 1-minus 14C glycine into urinary uric acid was measured, and the pool size and turnover of urate were assessed by renal excretion of simultaneously administered 15-N urate. Fructose caused an expansion of body urate pool in all subjects, while urate turnover was increased in four. The rate of incorporation of 14-C glycine into urinary uric acid corrected for extrarenal disposal was increased in all cases (21%-430%). In two patients, rates of incorporation of 14-C glycine into urinary creatinine were increased by 10% and 11%, while rates of incorporation into uric acid were increased 84% and 159%, respectively, as a result of fructose infusion. Specific enhancement of the rate of purine synthesis de novo was suggested by these findings. The rate of infusion appeared more important than total dose in determining the magnitude of this effect. Whether the increased rate of purine synthesis was a result of direct stimulation by a fructose metabolite or was secondary to fructose-induced purine nucleotide depletion is uncertain, since the kinetics of glycine incorporation were consistent with either mechanism. Erythrocyte PP-ribose-P concentrations, however, were diminished during infusion rather than increased as might be expected if fructose infusion stimulated purine synthesis by increasing availability of this regulatory substrate. 相似文献
96.
Denise L. Bonilla Charsey Cole-Porse Anne Kjemtrup Lynn Osikowicz Michael Kosoy 《Emerging infectious diseases》2014,20(10):1645-1651
Homeless persons in San Francisco, California, USA, have been shown to have head and body lice infestations and Bartonella quintana infections. We surveyed a self-selected population of homeless persons in San Francisco to assess infestations of head and body lice, risks of having body lice, and presence of B. quintana in lice. A total of 203 persons who reported itching were surveyed during 2008–2010 and 2012: 60 (30%) had body lice, 10 (4.9%) had head lice, and 6 (3.0%) had both. B. quintana was detected in 10 (15.9%) of 63 body lice pools and in 6 (37.5%) of 16 head lice pools. Variables significantly associated (p<0.05) with having body lice in this homeless population included male sex, African–American ethnicity, and sleeping outdoors. Our study findings suggest that specific segments of the homeless population would benefit from information on preventing body lice infestations and louseborne diseases. 相似文献
97.
98.
目的 建立加味逍遥散复方中丹参酮ⅡA的测定方法。方法 采用十八烷基硅烷键合硅胶柱(inertsil ODS-3柱 250 mm×4.6 mm,5 μm);流动相:乙腈-0.1%磷酸,进行梯度洗脱;检测波长:270 nm;流速:1.0 ml/min;柱温:20℃。结果 丹参酮ⅡA在0.0001~0.0005 μg范围内呈现良好的线性关系[r=0.9991,平均回收率为97.36%(RSD=1.38%,n=6)]。结论 本方法专属性强,准确度高,重现性良好,可用于加味逍遥散的质量控制。 相似文献
99.
目的 研究四逆散对Mdr2(Abcb4)基因缺陷(Mdr2-/-)小鼠胆汁淤积性肝纤维化的缓解作用,并探究其作用机制。方法 C57BL/6J小鼠作为对照组;C57BL/6J背景的Mdr2-/-小鼠作为模型小鼠,设模型组和四逆散低、高剂量(按生药量计为3.12、6.24 g·kg-1)组。四逆散组连续3周ig给予四逆散水提物,每天1次,对照组给予纯水。试剂盒法检测血清丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、总胆汁酸水平;取肝脏、脾脏称质量,计算肝脏、脾脏系数;结合小鼠肝组织HE染色,Masson染色,纤连蛋白(Fibronectin)、细胞角蛋白19(CK19)的免疫组化染色,明确四逆散对Mdr2-/-小鼠肝纤维化及胆汁淤积的影响。基于小鼠肝脏转录组学测序技术,挖掘四逆散改善Mdr2-/-小鼠肝损伤的作用靶点,并通过实时荧光定量PCR(qRT-PCR)法检测肝纤维化[fibronectin(Fn1)、胶原蛋白1(Col1a1)、角蛋白19(krt19)]、炎症[白细胞介素-1β(Il1β)、Il6、肿瘤坏死因子-α(Tnfα)、一氧化氮合成酶(Inos)]、细胞焦亡[凋亡相关斑点样蛋白(Pycard)、Il18]、胆汁酸合成[细胞色素P450家族成员7A1(Cyp7a1)]及转运[胆盐输出泵(Abcb11)、ATP结合盒转运蛋白(Abcc3)、钠离子-牛磺胆酸共转运蛋白(Slc10a1)]相关基因的转录水平。结果 与模型组比较,四逆散高剂量显著降低血清总胆汁酸的水平(P<0.05);明显缓解了Mdr2-/-小鼠肝脏中央静脉及胆管周围炎性细胞的浸润和胶原纤维的沉积,并显著抑制胆管反应的发生。转录组学及qRT-PCR结果共同表明,四逆散下调Mdr2-/-小鼠肝脏纤维化、炎症、细胞焦亡相关基因的转录(P<0.05);同时,四逆散下调胆汁酸合成关键限速酶调控基因Cyp7a1和调控胆汁酸向肝内转运的基因Slc10a1的转录,并上调调控胆汁酸外排的基因Abcb11、Abcc3的转录。结论 四逆散能缓解Mdr2-/-小鼠胆汁淤积性肝纤维化,机制可能与其调控炎症反应、细胞焦亡以及胆汁酸的合成和转运有关。 相似文献
100.
Very low density lipoproteins from guinea pig plasma, endogenously labeled with 3H in both the esterified and free cholesterol moieties, were obtained from serum collected 20 hr after the intravenous injection of 3H-cholesterol into donor animals. When these lipoproteins were injected into recipient guinea pigs, the esterified 3H-cholesterol was rapidly cleared from the plasma; 24% was in the liver in 5 min and 54% in 15 min. A smaller fraction of the esterified cholesterol appeared in other plasma lipoprotein fractions, with 3H in the low density lipoproteins reaching a peak of 9%-18% of the injected esterified 3H-cholesterol between 30 and 60 min after the injection. The results indicate that most of the esterified cholesterol in very low density lipoproteins of guinea pig plasma is removed directly by the liver and a minor fraction is transferred to low density lipoproteins. The pattern of labeling of cholesteryl esters of high density lipoproteins in these experiments suggests that their low concentration in the guinea pig is accompanied by a rapid turnover rate. 相似文献