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81.
G.-M. Robertz-Vaupel K. D. Lindecken T. Edeki C. Funke S. Belwon H. J. Dengler 《European journal of clinical pharmacology》1992,42(5):465-469
Summary In the present study the effect of metastatic liver disease on hepatic drug metabolism has been examined by studying the pharmacokinetics of antipyrine and the urinary excretion of antipyrine and its three major metabolites (4-hydroxyantipyrine, norantipyrine, and 3-hydroxymethylantipyrine) in 12 patients with extensive metastatic liver disease, and in 12 matched healthy controls.In the patients total liver volume, the volume of the liver parenchyma, and the volume of the liver metastases were determined by computed tomography. The volume of liver metastases always exceeded 35% of the total liver volume.There were no significant differences between the patients and controls in plasma half-life, plasma clearance, or apparent volume of distribution of antipyrine.The cumulative urinary excretion of antipyrine and its three major metabolites was significantly lower in patients [44 (18)%] than in controls [71 (8)%]. The excretion of antipyrine itself was unchanged and the decrease in cumulative excretion was due to reduced excretion of the three metabolites.The results show that the activity of the hepatic mixed function oxidases was not impaired even in patients with extensive metastatic liver disease. This may be because liver metastases do not cause a corresponding reduction in the volume of normal hepatic parenchyma. The decreased urinary excretion of the three major metabolites of antipyrine, which are mainly glucuronidated, may have been due to an alteration in the process of conjugation. 相似文献
82.
乳腺癌组织中Cyclin D1及p16蛋白表达的联合检测及其意义 总被引:3,自引:1,他引:2
目的:探讨乳腺癌中Cyclin D1及p16蛋白表达的相关性及其临床意义。方法:LSAB法检测多种乳腺组织中Cyclin D1及p16蛋白的表达情况,结合有关临床资料,分析Cyclin D1和p16蛋白表达异常与乳腺癌中重要的临床病理因素的关系。结果:62例乳腺癌组织中,Cyclin D1蛋白过度表达占48·4%,其表达与乳腺癌组织学分级呈明显正相关,且Cyclin D1蛋白过度表达更常见于ER、PR阳性的乳腺癌中。乳腺癌旁组织中Cyclin D1蛋白过度表达为20·0%,其他几种乳腺组织很少有CyclinD1蛋白的过度表达。p16蛋白仅在58·1%的乳腺癌组织中有表达,且p16的表达与组织学分级程度有负相关关系。正常乳腺组织中未见p16蛋白的异常。结论:乳腺癌组织中存在着Cyclin D1蛋白的过度表达及p16蛋白的异常,二者对乳腺癌组织的增殖分化有一定的影响。 相似文献
83.
继发性骨质疏松防治的研究 总被引:2,自引:1,他引:1
伍汉文 《中国现代医学杂志》2004,14(7):75-78
目的总结继发性骨质疏松预防与治疗的经验及提出见解.方法用钙代谢平衡的方法研究了钙代谢的基本情况,比较了补钙与不补钙在若干种生理状态对骨密度的影响,总结继发性骨质疏松的病因及对其采取不同方法的治疗经验.结果中国人膳食含钙量属于正常范围低水平状态,与适宜摄入量(AI)比较是不足的,在一定的生理状态下应予补钙.缺钙是原发性骨质疏松与继发性骨质疏松的不利因素.氟中毒骨病、糖尿病、性腺功能减退、肿瘤、糖皮质激素过多和甲亢均有其各别的病理生理,导致继发性骨质疏松,防治方法各异.结论从胚胎至老年都应防治骨质疏松.不同情况采取方法各异,但有效. 相似文献
84.
Masafumi Ogawa Yasuhiro Magata Yasuomi Ouchi Hidenao Fukuyama Hiroshi Yamauchi Jun Kimura Yoshiharu Yonekura Junji Konishi 《Brain research》1994,650(2):249-252
The effect of the cholinergic blocker, scopolamine on the cerebral blood flow (CBF) response to vibrotactile stimulation of a fore paw was studied using high-resolution positron emission tomography and H215O in 5 pentobarbital-anesthetized cats. Before scopolamine injection, the CBF response to the stimulation was found in the contralateral somatosensory cortex (mean ratio (contralateral/ipsilateral) control: stimulated1.02 ± 0.02: 1.17 ± 0.05; P < 0.01). After intravenous injection of scopolamine (0.35 mg/kg), the CBF response was abolished. However, the cerebral metabolic rate of glucose (CMRGlu) response to the same stimulation was unchanged after scopolamine injection in the same cats. We concluded that scopolamine abolishes the CBF response but not neuronal response to stimulation. We suggest that cholinergic mechanisms may play an important role for mediating CBF coupling to neuronal activity during physiological stimulation. 相似文献
85.
为探讨不同剂量水平的维生素K4及维生素D对绝经妇女骨折早期骨代谢的影响。选择年龄60~84岁(72.17±1.216岁),绝经女性骨折病人35例,随机分为4组,分别给予不同剂量的维生素K4及维生素D口服,实验进行20天。通过观察患者服药前后血清钙、血清磷、血清碱性磷酸酶、血清凝血酶原时间及血清骨钙素值的变化,综合评价维生素K、维生素D对老年妇女骨折早期骨代谢的影响。结果显示,不同剂量水平维生素K4、维生素D对绝经妇女骨折早期骨代谢的影响不同,有统计学意义。维生素K4对骨代谢的影响作用超过维生素D,并随剂量水平不同而差异有显著性。但维生素K4、维生素D对骨代谢的影响无交互作用。表明维生素D、维生素K4能促进骨折早期骨代谢,对骨折愈合有一定促进作用,且维生素K的作用强于维生素D。 相似文献
86.
Tomáš Šimůnek Martin Štěrba Olga Popelová Michaela Adamcová Radomír Hrdina Vladimír Geršl 《Pharmacological reports : PR》2009,61(1):154-171
The risk of cardiotoxicity is the most serious drawback to the clinical usefulness of anthracycline antineoplastic antibiotics, which include doxorubicin (adriamycin), daunorubicin or epirubicin. Nevertheless, these compounds remain among the most widely used anticancer drugs. The molecular pathogenesis of anthracycline cardiotoxicity remains highly controversial, although the oxidative stress-based hypothesis involving intramyocardial production of reactive oxygen species (ROS) has gained the widest acceptance. Anthracyclines may promote the formation of ROS through redox cycling of their aglycones as well as their anthracycline-iron complexes. This proposed mechanism has become particularly popular in light of the high cardioprotective efficacy of dexrazoxane (ICRF-187). The mechanism of action of this drug has been attributed to its hydrolytic transformation into the iron-chelating metabolite ADR-925, which may act by displacing iron from anthracycline-iron complexes or by chelating free or loosely bound cellular iron, thus preventing site-specific iron-catalyzed ROS damage. However, during the last decade, calls for the critical reassessment of this “ROS and iron” hypothesis have emerged. Numerous antioxidants, although efficient in cellular or acute animal experiments, have failed to alleviate anthracycline cardiotoxicity in clinically relevant chronic animal models or clinical trials. In addition, studies with chelators that are stronger and more selective for iron than ADR-925 have also yielded negative or, at best, mixed outcomes. Hence, several lines of evidence suggest that mechanisms other than the traditionally emphasized “ROS and iron” hypothesis are involved in anthracycline-induced cardiotoxicity and that these alternative mechanisms may be better bases for designing approaches to achieve efficient and safe cardioprotection. 相似文献
87.
S Gizurarson M Lorentzon T R?munddal F Waagstein L Bergfeldt E Omerovic 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2007,9(6):411-416
AIMS: Severe sustained bradycardia may cause acute and possibly chronic congestive heart failure (CHF). The aim of this study was to investigate acute and chronic effects of complete heart block (CHB) on cardiac function, morphology, and creatine (Cr) metabolism. METHODS AND RESULTS: CHB was induced in male Sprague-Dawley rats (approximately 250 g, n = 11) by means of electrocautery applied to the region of AV node and were compared with controls (n = 15). The rats were investigated at 1, 3, and 12 weeks after CHB induction with transthoracic echocardiography. Invasive haemodynamic assessment of left and right ventricular pressures was performed at 12 weeks. After the sacrifice, the hearts were freeze-clamped for analysis of myocardial Cr, and high energy phosphometabolites. The efficacy of operative procedure was 54%. The peri-operative mortality rate was 20%. Heart rate (HR) decreased by approximately 50% (P < 0.01) while stroke volume (SV) increased 2.5 times (P < 0.01) in the CHB rats. Cardiac index remained unchanged. The rats with CHB grew normally and were in no apparent distress. Filling pressures in left and right ventricles were normal. The CHB rats developed marked cardiomegaly with biventricular dilatation and eccentric left ventricular hypertrophy (P < 0.01). There was no change in the myocardial content of Cr and high energy phosphometabolites. CONCLUSION: Rats with CHB are compensating for reduction in HR with increased SV without haemodynamic and biochemical characteristics of CHF. This model may be useful to study the effects of CHB and bradycardia on myocardial structure, function, electrophysiology, and metabolism as well as for studies of cell therapy for reparation of AV conductance. 相似文献
88.
89.
母体钙代谢与补钙对妊娠的影响 总被引:1,自引:0,他引:1
妊娠期缺钙严重影响母婴的安全健康 ,其原因是由于妊娠期母体钙代谢发生变化 ,使母体血清游离钙离子浓度降低 ,血清铅浓度增高。有关研究表明 ,母体缺钙导致血铅竞争性过高 ,使胎儿身长、体重均小于胎龄儿 ,胎儿宫内发育迟缓的发生率增高 ,甚至发生早产、死胎等。同时发现血清钙离子可能对内源性一氧化氮合成释放起调节作用 ,而内皮素是最强的缩血管物质之一 ,母体补钙可调节一氧化氮与内皮素的平衡 ,从而降低妊高征的发生率。因此孕期补充钙剂是非常重要的。 相似文献
90.
Friedrich Manz Hermann Kalhoff Thomas Remer 《Pediatric nephrology (Berlin, Germany)》1997,11(2):231-243
In early infancy, complex disorders of acid base metabolism are more frequent than in any other age group, with a predisposition
to metabolic acidosis due to an age-related low renal capacity for acid excretion and an unphysiologically high actual renal
acid load in nutrition with common formulas. Recently in preterm and small-for-gestational-age infants, persistent maximum
renal net acid excretion (NAE) with subnormal or normal blood acid base status, impaired weight gain, and adaptive hormonal
reactions have been observed. Incipient late metabolic acidosis is one example of a mixed disorder of acid base metabolism
with maximum renal NAE in early infancy. Alkali therapy is highly effective and can be realized both on an individual basis,
using urine pH screening as a diagnostic criterium for maximum renal acid stimulation, or on a general preventive level using
modified standard formula with a reduced actual renal NAE similar to that seen on alimentation with human milk. From an integrated
point of view, the low glomerular filtration rate and renal capacity for acid excretion beyond the developmental age of more
than 44 weeks, may well be interpreted as the result of a specific adaptation to breast feeding sparing energy, and thus an
evolutionary advantage for the survival of mother and child.
Received July 10, 1996; received in revised form and accepted October 7, 1996 相似文献