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51.
鱼腥草的有效成分、药理作用及临床应用的研究进展 总被引:92,自引:1,他引:91
鱼腥草中含有癸酰乙醛、癸醛、月桂醛及甲壬酮等成分,其中癸酰乙醛具有抗病原微生物活性.药理研究证明鱼腥草具有抗菌、抗病毒、增强机体免疫、抗炎等作用,故在呼吸科、五官科及消化科疾病中都有广泛的应用. 相似文献
52.
Ajit K. Shah Richard C. Brundage Kathleen D. Lake Ronald J. Sawchuk 《Biopharmaceutics & drug disposition》1995,16(1):59-70
We estimated the free fraction (fu) of cyclosporine (CyA) in the plasma from concentrations of CyA in urine (Cu) and plasma (Cp), urine flow rate (UF), and glomerular filtration rate in rabbits and in heart transplant patients. Following intravenous administration of CyA (5–30 mg kg?1) in ten NZW rabbits and oral administration of CyA (4.8–12.1 mg kg?1) in nine heart transplant patients, CyA concentrations in urine and plasma were measured by HPLC. The ratios of Cu to Cp and UF data were fitted to a physiological model of renal clearance using NONMEM. The free fraction of cyclosporine in the rabbits and the heart transplant patients was 0.0122 and 0.14, respectively. Because of the relatively low permeability of CyA across the tubular epithelium, no apparent equilibrium between Cu and Cp at any urine flow rate was reached and, therefore, the Cu to Cp ratio will not be equal to fu. 相似文献
53.
An immunohistochemical study of melanocytic tumours using 19A2, a monoclonal antibody against proliferating cell nuclear antigen (PCNA/cyclin), was performed on tissues routinely processed with formalin fixation and paraffin embedding. In normal skin, keratinocytes of the suprabasal region in epidermis, the papillae and outer root sheath of hair follicles and the basal cells lining the lobules of sebaceous glands were stained in the nucleus. Other skin components, including basal and follicular melanocytes, did not demonstrate nuclear labelling. In addition, expression of PCNA/cyclin in keratinocytes was higher in sun-exposed skin compared with unexposed skin. In melanocytic lesions, PCNA/cyclin positive tumour cells increased in number and staining intensity according to the following progression: common melanocytic naevi; dysplastic naevi; primary melanomas; and metastatic melanomas. Expression of PCNA/cyclin, therefore, provides a useful marker for proliferation and tumour progression in skin. 相似文献
54.
粪便隐血试验是检测消化道微量出血的重要手段。本文用三种隐血试验:血红蛋白定量试验(HQT)、反向间接血球凝集试验(RPHA)和联苯胺试验(BT)对不同消化道疾病患者的粪便进行检测。结果表明隐血的检出用HQT和RPHA较BT更为特异和敏感。 相似文献
55.
二维超声心动图对高原婴幼儿右室射血分数的估测 总被引:2,自引:0,他引:2
目的:将二维超声测量右室射血分数(RVEF)的方法应用于临床。方法:用心尖四腔观单平面面积-长度法测量43例高原正常婴幼儿RVEF,并与40例患右室扩张肥厚型心肌病(RVDCHM)婴幼儿进行了比较。结果:健康组RVEF均值为58.20%,标准差为7.24%;患儿组均值为36.10%,标准差为7.01%,两组测量的RVEF有非常显著差异(P<0.001)。结论:心尖四腔观单平面面积-长度法测量RVEF可作为估测右室收缩功能的简单可靠的方法。 相似文献
56.
胸腺免疫抑制组分的抗变态反应作用 总被引:1,自引:0,他引:1
整体实验表明,胸腺免疫抑制组分肌内注射1wk对大鼠被动皮肤过敏反应(8、20、50和125mg·kg-1)兔Arthus反应(4和12mg·kg-1)均有明显的抑制作用。体外实验表明,该药能抑制致敏豚鼠离体回肠平滑肌的过敏性收缩,IC50为446.7mg·L-1。上述结果表明,胸腺免疫抑制组分有抗Ⅰ和Ⅲ型变态反应的作用。 相似文献
57.
H-C. HSIA H-C. LIN F-Y. LEE Y-T. TSAI S-D. LEE H-C. MENG Y. CHAO S-S. WANG K-J. LO 《Journal of gastroenterology and hepatology》1993,8(1):15-20
Abstract Somatostatin has been used to effectively control acute variceal haemorrhage, with conjectured mechanisms on portal hypertension. We, therefore, evaluated the effects of somatostatin on hepatic and systemic haemodynamics in 15 patients with hepatitis B-related cirrhosis and portal hypertension. All patients received an intravenous, continuous infusion of somatostatin 250 μg/h, following a bolus injection of 250 μg. In systemic haemodynamics, the mean arterial pressure (MAP) increased ( P < 0.05), associated with a reflex bradycardia within 3 min following bolus injections, compared with basal values. The right atrial pressure, pulmonary capillary wedge pressure, inferior vena cava pressure, cardiac index, and systemic vascular resistance remained unaffected after drug infusion. In hepatic haemodynamics, the wedge hepatic vein pressure remained unchanged after drug administration. However, there was an increase in free hepatic vein pressure (FHVP; P < 0.05), and a trend toward a decrease in the hepatic vein pressure gradient (HVPG; P = 0.063), within 3 min after bolus injection. Furthermore, the hepatic blood flow decreased significantly at 10 and 30 min after somatostatin infusion ( P < 0.05). The effective sinusoidal perfusion assessed by indocyanine green infusion also decreased progressively at 10 min ( P = 0.057) and 30 min ( P < 0.05). We concluded that somatostatin, at the dose used in this study, caused a transient and bolus-related vasoconstrictive effect, resulting in increases in MAP and FHVP, a decrease in heart rate, and a trend toward lower HVPG. In addition, somatostatin reduced the hepatic blood flow and effective sinusoidal perfusion which may be hazardous to cirrhotic patients during variceal haemorrhage. 相似文献
58.
A breathing lung phantom for 81mKr lung ventilation studies its use in dosimetry and quality control
J. A. J. Camps C. Zuur J. A. K. Blokland J. J. Broerse E. K. J. Pauwels 《European journal of nuclear medicine and molecular imaging》1988,14(11):529-532
The construction of a breathing lung phantom that can be used to measure the amount of radioactive gas in the lungs as well as to determine the absorbed dose is described. For a lung ventilation study that consists of 6 views of 300 kents each, an effective dose equivalent of 50 Sv was calculated. The phantom is also suitable for comparison of different generator systems. 相似文献
59.
Robert H. Smallwood George W. Mihaly Richard A. Smallwood Denis J. Morgan 《Journal of pharmacokinetics and pharmacodynamics》1988,16(5):529-542
For substances eliminated from blood by the liver, the effect of a change in unbound fraction of drug (fu
b
)on steady state total (C
b
)and unbound (Cu
b
)blood concentrations has hitherto only been considered for the two limiting cases, i.e., at the upper and lower extremes of hepatic intrinsic clearance (CL
int
).For a substance of very low CL
int
,if fu
b
changes, C
t
will change and Cu
b
will remain constant, whereas if CL
int
isvery high, Cu
b
will change and C
b
will remain constant.The present study defines the effects of a change in fu
b
on C
b
and Cu
b
over the whole CL
int
range. Computer simulations were undertaken which predicted that, for a given change in fu
b
,absolute and relative changes in C
b
would decreasenonlinearly with increasing CL
int, twhile the relative change in Cu
b would increasewith CL
int
.The absolute change in Cub
would be independent of CL
int
.Significant changes in Cb and Cu
b would be observed at intermediate values of CL
int not just at the high and low extremes. These theoretical predictions were investigated experimentally in the isolated perfused rat liver by examining the effects of a change in fu
b of sodium taurocholate a substance with intermediate CL
int
(such that at fu
b
=0.27,hepatic extraction ratio=0.71) induced by concurrent administration of sodium oleate. Sodium 24-
14
C-taurocholate (specific activity 52 Ci/mmol) was infused into the reservoir in a recycling system at 30 mol/hr for 105 min (n=6). At 45 min a bolus dose of sodium oleate (50 mmol) was administered to the reservoir, followed by a constant infusion of 143 mmol/hr for 1 hr. Following the administration of oleate, taurocholate fu
b fell promptly by 55% (0.27–0.12). There was a relative increase of taurocholate C
b of 22.7% and a relative decrease in Cu
b of 45.4%, in accordance with the simulations (p<0.05). We conclude that important changes in unbound steady-state concentration, the pharmacologically active moiety, can occur upon changes in unbound fraction with compounds of intermediate hepatic intrinsic clearance.This study was supported by the National Health and Medical Research Council of Australia. 相似文献
60.
背景 血栓栓塞(TE)事件是肥厚型心肌病(HCM)的重要并发症。目前针对HCM患者TE事件的风险预测,仅国外学者构建了两个模型:HCM Risk-CVA及French HCM score,然而,现有研究发现HCM Risk-CVA模型对于中国HCM患者的临床价值较为有限。目的 本研究拟构建适合中国HCM患者的TE事件风险预测模型。方法本研究系回顾性队列研究,收集2010—2018年在四川大学华西医院就诊的537例HCM患者的病例资料。本研究通过电话随访或电子病历系统查询患者就诊记录,每6~12个月随访1次,直至出现终点事件或死亡或研究拟定的评估日期(2019-12-31),终点事件定义为复合性TE事件。采用单因素和多因素Cox回归分析构建风险预测模型,并使用自助重抽样的方法进行内部验证。结果 537例患者中,24例患者有不同程度的数据缺失,最终纳入513例患者。中位随访时间为4.2(1.3,6.2)年,随访过程中42例(8.18%)发生TE事件,年发病率为2.10%[95%CI(1.47%,2.73%)]。根据多因素Cox回归模型构建TE事件风险预测模型,最终纳入年龄、既往TE事件、心... 相似文献