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51.
CHRISTOPH STELLBRINK KLAUS-PETER KUNZE PETER HANRATH 《Pacing and clinical electrophysiology : PACE》1995,18(9):1717-1720
STELLBRINK, C., et al .: Preexcitation in Hypertrophic Cardiomyopathy: A Case of a Fasciculoventricular Mahaim Fiber . A patient with hypertrophic cardiomyopathy (HCM) who presented with preexcitation pattern on the surface ECG suggestive of the Wolff-Parkinson-White (WPW) syndrome is described. Intracardiac electrophysiological study revealed a fixed anomalous QRS complex and a short fixed His-ventricular interval indicating a fasciculoventricular Mahaim fiber. As this specific form of accessory connection does not cause reentrant tachycardias, no treatment was required. It is important to distinguish this entity from atriofascicular or nodoventricular Mahaim fibers or the WPW syndrome in patients with HCM showing a preexcitation pattern in the surface ECG, as these may cause life-threatening arrhythmias in this patient population. 相似文献
52.
粉防己碱和氯丙嗪对人胚肺成纤维细胞胶原和透明质酸合成的影响(英文) 总被引:4,自引:0,他引:4
目的:研究粉防己碱(Tet)和氯丙嗪(Chl)对人胚肺成纤维细胞胶原与透明质酸(HA)合成的影响,为应用钙拮抗剂防治器官纤维化提供依据.方法:采用[~3H]脯氨酸掺入和放射免疫法分别测定胶原与HA合成.结果:Tet 5—80 μmol L~(-1)和Chl 10—40 μmol L~(-1)均以浓度依赖方式抑制胶原与HA合成.Tet 5—20μmol L~(-1))对细胞无明显毒性却显著抑制胶原与HA合成(P<0.01).结论:Tet在低浓度(5—20μmol L~(-1))时对细胞无明显毒性作用而显著抑制成纤维细胞胶原与HA合成,可望成为治疗器官纤维化的有效药物. 相似文献
53.
本文采用中性洗涤剂法测定了广东78种食物的不溶性膳食纤维含量,结果提示,不溶性膳食纤维的平均含量:干豆坚果类为7.12%,鲜果类为1.93%,根茎类为1.55%,叶菜类为1.31%,粮谷类为1.27%,茄瓜类为1.15%。其中干豆坚果类与茄瓜类、粮谷类、叶菜类、根茎类和鲜果类的含量差别极显著(P<0.01),而后五类食物的含量相互间差别不显著(P>0.05)。粮谷类的变异系数较大(CV:142%)。其中以加工较深的米面及其制品较低(0.31%—0.72%),而未深加工的玉米、薏米的含量则高(2.48%—6.08%)。 相似文献
54.
I. Gorai Y. Taguchi O. Chaki M. Nakayama H. Minaguchi 《Calcified tissue international》1997,60(4):317-322
Urinary excretion of cross-linked N-telopeptide of type I collagen (NTx) has been reported to be a specific marker of bone
resorption [18]. We assessed a new immunoassay for NTx as an indicator of changes in bone resorption caused by spontaneous
menopause and compared cross-sectionally the levels of urinary NTx, hydroxylysylpyridinoline (HP), lysylpyridinoline (LP),
hydroxyproline (OH-Pr), other serum biochemical indices, and lumbar spine and proximal femur bone mineral density (BMD). Eighty-one
Japanese women aged 22–77 participated in this study; 36 were premenopausal and 45 were postmenopausal. Urinary HP, LP, and
NTx stayed at low levels in the premenopausal period and rose 21%, 30%, and 67% in the postmenopausal period, respectively.
The rise in LP and NTx was statistically significant (P < 0.01), suggesting that NTx is mostly released from bone matrix when bone resorption is accelerated. When premenopausal
women were divided into two age groups and postmenopausal women were divided into two groups according to years since menopause
(YSM) there were significant differences in LP and NTx between women <4 YSM and women aged <40 and those women aged 41+ (P < 0.01 and P < 0.05, respectively). A significant 110% increase in urinary NTx and a 48% increase in urinary LP were observed in postmenopausal
women compared with age-matched premenopausal women aged 45–55. All biochemical markers other than serum PTH correlated significantly
with each other (r = 0.243–0.858, P < 0.05–0.0001). Urinary NTx inversely correlated with lumbar spine BMD. When postmenopausal women were divided into three
groups, the correlation between bone resorption and formation markers in women 0-1 YSM was greater than in women 2–10 YSM
and in women 11 + YSM, indicating that resorption and formation are coupled at the early postmenopausal period. We conclude
that urinary NTx is responsive to changes in bone metabolism caused by estrogen deficiency and may be a more sensitive and
specific marker than HP, LP, or OH-Pr in the early postmenopausal years.
Received: 15 February 1995 / Accepted: 18 October 1996 相似文献
55.
56.
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
57.
复合膳食纤维对大鼠体内脂质过氧化作用的影响 总被引:5,自引:1,他引:4
制备复合膳食纤维 (dietaryfiber,DF) ,并分别探讨复合、混合及三种单一的DF对高脂血症大鼠体内脂质过氧化作用的影响。选健康、断乳Wistar大鼠 6 4只 ,按体重随机分为 8组 ,用高脂饲料诱发高脂血症的同时 ,分别添加 10 %的DF :纤维素 (B组 )、果胶 (C组 )、海藻酸钠 (D组 )、纤维素 -果胶复合物 (E组 )、纤维素 -海藻酸钠复合物 (F组 )、纤维素 -果胶混合物 (G组 )、纤维素 -海藻酸钠混合物 (H组 ) ,以单纯的高脂饲料组为对照组 (A组 ) ,观察各种DF对大鼠的生长发育及脂质过氧化作用的影响。结果显示 :1、添加 10 %的各种DF不影响大鼠的生长发育。 2、各种DF皆可显著升高血清超氧化物歧化酶 (SOD) (P <0 0 1)、谷胱甘肽过氧化物酶 (GSH Px)活性 (P <0 0 1) ,降低丙二醛 (MDA)水平 (P <0 0 5 ,B、D组除外 ) ,提高红细胞膜的流动性 (P <0 0 5 ) ,以复合物、混合物效果为明显。 3、各种DF可不同程度地增加粪重和粪脂排出量 (P <0 0 5 ,D组除外 ) ,以复合物、混合物为明显。提示各种DF皆可不同程度地降低大鼠体内脂质过氧化作用 ,提高红细胞膜的流动性 ,其中可溶性DF效果优于不可溶性DF ,而复合、混合DF的效果又优于单一的DF ,且以复合物效果为佳 相似文献
58.
J. M. Greally L. Y. Boone S. G. Lenkey S. L. Wenger M. W. Steele 《American journal of medical genetics. Part A》1992,44(3):334-339
A child with manifestations of acrogeria and metageria, two “premature aging” syndromes, is presented. Because of his indistinct phenotype and because the question has been previously raised as to whether these conditions are separate, we propose the designation of acrometageria to describe this phenotypic continuum. As there is much in common clinically between acrometageria and the syndrome of type III procollagen deficiency (Ehlers-Danlos type IV), it might be presumed that a similar pathogenesis for acrometageria exists. This possibility has been tested previously, without demonstrating specific quantitative or qualitative deficits, but with some indirect evidence that collagen metabolism is deranged in these patients. One such crude indicator is the elevation of urinary hyaluronic acid levels, demonstrated in our patient and also observed in the phenotypically distinct Werner and Hutchinson-Gilford premature aging syndromes. On one hand, it could be argued that this supports the concept that premature aging syndromes exist as a biological continuum. On the other hand, it is equally valid to argue that syndromes of premature aging are so described merely because they include recognizable changes of normal aging and that the demonstration of an underlying mutation in a collagen gene, for example, invalidates their study as models of accelerated normal aging. © Wiley-Liss, Inc. 相似文献
59.
Hideto SAKAI Kiichiro JINDE Noboru SAOTOME Wei SUNG Mitsunori YAGAME Yasuo NOMOTO Masanobu MIYAZAKI Takashi HARADA 《Nephrology (Carlton, Vic.)》1997,3(1):91-94
Summary: In situ hybridization of mRNA for collagen IV, collagen VI, stromelysin (MMP-3) and TIMP1 was examined in renal biopsy specimens from patients with IgA nephropathy (IgAN) or diabetic nephropathy with various degrees of tissue damage. The majority of cells in the glomeruli expressed these mRNA almost simultaneously, but a few cells demonstrated positive expression for only one of these probes. There was a parallel relationship between the degree of tissue damage and that of mRNA expressions of these probes in patients with IgAN, while patients with diabetic nephropathy showed a reverse relationship between these two parameters. It is concluded that patients with mesangial proliferative glomerulonephritis expressed mRNA for collagen collagenase and its inhibitor in the glomeruli in parallel with the progress of tissue damage. In contrast, glomerular samples from patients with diabetic nephropathy showed that there was an inverse relationship between tissue damage and expression of mRNA. It is concluded that expression of collagen, collagenase and its inhibitor parallels the progression of glomerular changes in IgAN, but such parallel expression was not observed in patients with diabetic nephropathy. 相似文献
60.
Induction of type II collagen-specific antibody production in blood lymphocyte cultures of rhesus monkeys (Macaca mulatta) with collagen-induced arthritis using the immobilized native antigen. 下载免费PDF全文
Peripheral blood mononuclear cells (PBMC) from Rhesus monkeys previously immunized with bovine type II collagen to induce arthritis were cultured with the same antigen. Because the native protein is poorly soluble in culture medium a heating step is often used. The antigen in this form induced PBMC proliferation, but epitopes for the induction of antibody production and arthritis were lost. To keep the native protein intact it was coated on affigel beads. With the immobilized antigen specific antibody production could be induced. 相似文献