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71.
Emilio Bombardieri Antonia Martinetti Rosalba Miceli Luigi Mariani Maria Rita Castellani Ettore Seregni 《European journal of nuclear medicine and molecular imaging》1997,24(11):1349-1355
Bone scintigraphy plays a major role in the diagnosis of bone metastases. The clinical utility of new biochemical markers
of bone metabolism has recently been investigated in various bone diseases. This study evaluated the role of some bone metabolism
markers in comparison with bone scan in the follow-up of breast cancer patients. We studied 149 patients with breast cancer,
33 (22%) of whom had bone metastases. IRMAs were used for the evaluation of blood levels of osteocalcin, bone alkaline phosphatase
(BAP), the C-terminal propeptide of type I procollagen and the C-terminal cross-linked telopeptide of type I collagen (ICTP).
Multivariate regression analysis showed that menopausal status (P=0.007) and metastatic bone lesions (P=0.001) affected bone marker levels. When considering post-menopausal women, the only subset in which bone metabolism marker
behaviour could be reliably investigated, we found a high degree of overlap in marker distribution for scan-positive and scan-negative
patients. Discrimination between scan-negative and scan-positive patients based on the above markers, taken singly or jointly,
was assessed by means of logistic discriminant analysis. The best discrimination was achieved with BAP, closely followed by
ICTP. BAP and ICTP together gave a slight improvement over the use of the two markers separately. However, even in this case
the degree of discrimination was poor and its clinical utility was limited. In fact, to achieve a specificity of 95%, the
sensitivity of the test was about 20%; conversely, with a sensitivity of 95%, the specificity was below 10%. In conclusion,
based on our findings, we believe that blood levels of the investigated markers cannot replace bone scintigraphy in the follow-up
of breast cancer patients for the early detection of bone metastases.
Received 14 April and in revised form 5 July 1997 相似文献
72.
早期肠道营养对烧伤后肠源性高代谢的影响 总被引:9,自引:1,他引:8
从80年代末起,通过对600只大(豚)鼠、60只兔和60头小香猪所建立的4种烧伤后早期营养的动物模型,以及21例严重烧伤病人对比分析,发现烧伤后早期肠道喂养可改善胃肠道血流供应,减轻肠道缺血再灌流损伤;可维护肠粘膜结构以及吸收、分泌、运动功能,降低门脉、中心静脉血内毒素水平,减少肠道内毒素易位;可降低伤后枯否细胞获得数、吞噬墨汁枯否细胞数和面积,以及其培养上清中肿瘤坏死因子(TNF)量,对伤后枯否细胞的活化有刺激作用;可降低血胰高糖素、皮质醇、儿茶酚胺、TNF、IL-8前列腺素E2(PGE2)等递质的水平,降低高代谢,使烧伤45%成人静息能量消耗(REE)在烧伤后4、8、14d的均值降低28.6%。通过相关分析发现REE与血丙二醛(MDA)、内毒素、分解激素、TNF均呈显著正相关(r=0.7386~0.9922,P<0.05~0.01)。 相似文献
73.
Mitsuhiko Yanagisawa Rumiko Hosoki Masanori Otsuka 《European journal of pharmacology》1992,220(2-3):111-117
We have developed an isolated spinal cord-skin preparation of the newborn rat. The spinal cord together with a piece of skin connected to the cord by the saphenous nerve was isolated from 1- to 4-day-old rats and separately superfused with artificial cerebrospinal fluid in two neighbouring chambers. Potentials were recorded extracellularly from the third lumbar ventral root. Application of capsaicin (0.5-2 μM) or KCl (60–350 mM) with brief pressure pulses to the perfusion bath of the skin evoked a depolarizing response of 20- to 40-s duration in the ventral root. The response was depressed by [Met5]enkcphalin (0.03–3 μM). morphine (0.1–2 μM) and a tachykinin antagonist, [D-Arg1,D-Trp7,9,Leu11] substance P (spantide), 1–10 μM), applied to the spinal cord by superfusion, whereas the response was augmented by centrally administered calcitonin gene-related peptide (0.1–0.2 μM) or bicuculline (0.5–1 μM). 相似文献
74.
Seven subjects underwent a standard localized exercise of calf muscles in order to investigate whether the metabolic exercise-induced steady-state, as revealed by the evaluation of inorganic phosphate/phosphocreatine ratio, depends on the conditioning of the muscle just prior to the exercise. The experimental protocols consisted of two separate experiments using first [31P]nuclear magnetic resonance spectroscopy and second (on 3 subjects) infrared oxyphotometry to respectively follow variation of energy metabolism and tissular deoxygenation. The exercise consisted of 240 successive plantar flexions (0.5 Hz frequency) against a high load equivalent to SO% of the maximal voluntary contraction. This exercise was accomplished before cold exercise and after warm exercise, a warming-up period bringing to approximately 50% of Vo2max. The results showed that: (1) steady-state level of phosphate/phosphocreatine and intracellular acidosis was significantly lowered by warming-up; (2) cold and warm exercise steady-state of calculated adenosine diphosphate values were not significantly different; (3) cold exercise rapidly induced a high tissular deoxygenation that is not observed during warm exercise; and (4) time-constant of phosphocreatine resynthesis is lowered after warm exercise but the initial slope of time-evolution is not modified. Parallel experiments also showed that phosphate/phosphocreatine steady-state was not modified in comparison with warm exercise when the same power of exercise was reached by stepwise incrementation of the charge. From these results we postulate that a better tissue oxygenation due to a global or localized warming-up allows to reach the same mechanical performance with a lower decrease of PCr content, owing to a faster adjustment of oxidative metabolism during the transitional period. However the aerobic pathway flux during the steady-state is probably the same before and after the warming-up despite different values of phosphate/phosphocreatine. As a consequence it can be assumed that this ratio is not a good indicator of the rate of muscle oxidative metabolism during the steady-state phase of the exercise. 相似文献
75.
C. A. Nienaber 《Clinical physiology and functional imaging》1994,14(3):337-348
Summary. The development of positron emission tomography (PET) in the clinical environment along with the synthesis of biologically active molecules and tracer kinetic principles has provided a diagnostic tool for in vivo tissue characterization in humans. Moreover, based on the growing knowledge of cellular function on the molecular level of diseases PET biological imaging has stimulated the synthesis of numerous metabolic compounds labelled with the four primary positron-emitting radioisotopes C-ll, F-18, N-13 and 0–15. While the concept of biological imaging has gained attraction for probing both the central nervous system and neoplastic tissues, current diagnostic benefit from PET is probably best defined in cardiovascular medicine. 相似文献
76.
目的 探讨感觉神经肽P物质(SP)对离体培养的肉芽组织成纤维细胞表皮生长因子(EGF)表达的调控作用及特点。方法 采用甲醛注射的方法造成Wistar大鼠局部无菌性炎性反应,提取肉芽组织进行成纤维细胞原代培养;采用逆转录—聚合酶链反应(RT—PCR)方法检测SP对肉芽组织成纤维细胞EGF基因表达的调控作用,观察时间及剂量—效应关系;采用Western-blotting方法检测EGF蛋白表达情况,观察时间及剂量—效应关系。结果 10^-7mol/L SP可诱导成纤维细胞EGF mRNA的表达,在作用后6h与对照组比,差异有显著性(P<0.01);SP在10^-8-10^-6mol/L范围内可以显著促进成纤维细胞EGF mRNA表达,在10^-7mol/L达到峰值,10^-5mol/L时与对照组差异无显著性(P>0.05)。10^-7mol/L SP作用12h后可检测到EGF蛋白明显表达增强(P<0.01),24h达高峰,48h后逐渐有所回落。SP在在10^-8--10^-5mol/L范围可诱导EGF蛋白的表达,均在10^-7mol/L剂量点达到峰值(P<0.01)。结论 SP可诱导肉芽组织成纤维细胞EGF基因和蛋白的表达,且呈现出一定的时间和剂量特点,在SP调控创伤愈合的作用中具有重要意义。 相似文献
77.
目的 探索LDH实验检测细胞活力的可行性。方法 原代培养骨髓细胞和软骨细胞,用LDH实验测定上述两组细胞的活力,并与镜下活体观察到细胞的生长状况相比较。与目前比较成熟的测定细胞活力的MTS实验的测得的值相比较。结果 LDH实验对上述两组细胞的活力的测定结果与镜下活体观察到的结果相符合。与MTS实验的测得的结果经统计学处理无显著差异。结论 LDH实验可用于细胞活力的直接测定,而对活细胞的生存、繁殖无影响。 相似文献
78.
α<Subscript>2β</Subscript> adrenoreceptor 301–303 deletion polymorphism in polycystic ovary syndrome
Alexandros D. Saltamavros George Adonakis Sosanna Kritikou Vasiliki Koika Kleanthis Koufogiannis Kostas Spyropoulos George Kourounis Christodoulos Flordellis Venetsana Kyriazopoulou Neoklis A. Georgopoulos 《Clinical autonomic research》2007,17(2):112-114
α2β adrenoreceptor 301–303 deletion polymorphism does not influence basal metabolic rate, insulin resistance or weight gain in
Greek women with polycystic ovary syndrome. 相似文献
79.
2型糖尿病并脂肪肝与血脂紊乱的关系探讨 总被引:2,自引:0,他引:2
目的 探讨 2型糖尿病并脂肪肝患者与脂代谢紊乱之间的关系。方法 对 60例 2型糖尿病并脂肪肝和 5 2例 2型糖尿病不并有脂肪肝病例的血脂谱 ,空腹血糖 (FPG ) ,餐后 2小时血糖 ( 2hPG) ,空腹胰岛素 (FINS)进行测定 ,计算体重指数 (BMI)及胰岛素敏感指数 (ISI)。结果 2型糖尿病并脂肪肝与不并脂肪肝相比 ,甘油三脂 (TG) ,低密度脂蛋白胆固醇 (LDL -C) ,FINS均升高 (P <0 .0 5 ,P <0 .0 1) ,而ISI明显降低 (P <0 .0 1)、脂蛋白a(Lp(a)降低(P <0 .0 5 )。结论 2型糖尿病并脂肪肝比不并脂肪肝者存在明显脂代谢紊乱及胰岛素抵抗 相似文献
80.
Peter R. Martin Sondra Levin Giovanni Impeduglia Yoomi Choe John Karanian Anil B. Mukherjee 《Psychopharmacology》1989,97(2):253-256
To determine whether prenatal thiamine deficiency, a frequent concomitant of alcoholism, reduces the response to ethanol during adulthood in the rat as does ethanol exposure in utero (Abel et al. 1981), pregnant Sprague-Dawley rats received either control or thiamine deficient diets together with daily injections of the thiamine antagonist pyrithiamine. At 7 months of age, male offspring were exposed to precisely regulated ethanol vapor concentrations in an inhalation chamber for 24 h and blood ethanol concentrations (BECs) and ethanol-induced intoxication were determined. Prenatally thiamine deficient rats and controls were indistinguishable in terms of appearance, body and liver weights, and the ratios of liver to body weight and brain to liver weight. However, total body water was significantly greater, and BECs and behavioral impairment were decreased, in the experimental rats. These findings indicate that prenatal thiamine deprivation is associated with reduced pharmacologic effect of ethanol as a result of increases in its volume of distribution and rate of metabolism. 相似文献