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1.
Jürgen Schlegel Beate Ullrich Gabriele Stumm Peter Gass Ina-Maria Harwerth Nancy E. Hynes Marika Kiessling 《Acta neuropathologica》1993,86(5):473-479
The present study investigated the expression of c-erbB-2 in 59 meningiomas, including different histological subtypes and anaplastic variants, by immunocytochemistry and molecular biological techniques. Immunohistochemistry using the monoclonal antibody FWP-51 directed against c-erbB-2-encoded oncoprotein gp185 demonstrated variable degrees of immunoreactivity in all meningiomas. The intensity of immunostaining correlated with the degree of expression as assessed by Western analysis in 28 meningiomas using polyclonal antiserum 21N. There was no correlation between the degree of expression and histological variants. Immunoreactivity of all menigiomas was distinctly less intense, however, than that of the human breast cancer cell line SK-BR-3, and slightly lower than that of brain metastases of breast and ovarian carcinomas that served as positive controls for both methods. By Southern analysis all meningiomas showed a single copy of the c-erbB-2 gene. Non-neoplastic arachnoid cap cells also exhibited c-erbB-2 expression and the degree of immunoreactivity was comparable with the majority of meningiomas. These data argue against an overexpression of c-erbB-2 in meningiomas, but rather indicate a cell-type-specific constitutive expression of the c-erbB-2 gene product in meningiomas and their putative progenitor cells. Since a subgroup of meningiomas is known to express progesterone receptors (PR), gp185 immunoreactivity was compared to the hormone receptor status using monoclonal antibody KD68. Fifty-six percent meningiomas showed PR immunoreactivity, but there was no statistically significant correlation with the degree of gp185 expression.This study was supported by a grant of the Tumorzentrum Heidelberg/Mannheim (M.K., No. 10028060) 相似文献
2.
肱骨干骨折--髓内钉与钢板固定的比较 总被引:1,自引:1,他引:0
MohidBhandari JosephR BeateP.Hanson DanC.Norvell 《中华创伤骨科杂志》2004,6(6):676-680
总体而言,这些报道提示:采用髓内钉治疗肱骨干骨折较采用钢板带来更多的并发症,尤其是采用顺行人路。同时,这些报道没有提供确切的证据证明何种方法在骨折愈合、减少感染或上肢总体功能上优于另一种。 相似文献
3.
Yanfei L Ma Qingqiang Zeng David W Donley Louis-Georges Ste-Marie J Christopher Gallagher Gail P Dalsky Robert Marcus Erik Fink Eriksen 《Journal of bone and mineral research》2006,21(6):855-864
Transiliac bone biopsies were obtained from 55 women treated with teriparatide or placebo for 12-24 months. We report direct evidence that modeling bone formation at quiescent surfaces was present only in teriparatide-treated patients and bone formation at remodeling sites was higher with teriparatide than placebo. INTRODUCTION: Recombinant teriparatide [human PTH(1-34)], a bone formation agent for the treatment of osteoporosis when given once daily subcutaneously, increases biochemical markers of bone turnover and activation frequency in histomorphometry studies. MATERIALS AND METHODS: We studied the mechanisms underlying this bone-forming action of teriparatide at the basic multicellular unit by the appearance of cement lines, a method used to directly classify surfaces as modeling or remodeling osteons, and by the immunolocalization of IGF-I and IGF-II. Transiliac bone biopsies were obtained from 55 postmenopausal women treated with teriparatide 20 or 40 microg or placebo for 12-24 months (median, 19.8 months) in the Fracture Prevention Trial. RESULTS: A dose-dependent relationship was observed in modeling and mixed remodeling/modeling trabecular hemiosteons. Trabecular and endosteal hemiosteon mean wall thicknesses were significantly higher in both teriparatide groups than in placebo. There was a dose-dependent relationship in IGF-II immunoreactive staining at all bone envelopes studied. The greater local IGF-II presence after treatment with teriparatide may play a key role in stimulating bone formation. CONCLUSIONS: Direct evidence is presented that 12-24 months of teriparatide treatment induced modeling bone formation at quiescent surfaces and resulted in greater bone formation at remodeling sites, relative to placebo. 相似文献
4.
Contractile properties of in situ perfused skeletal muscles from rats with congestive heart failure 总被引:3,自引:0,他引:3
Per Kristian Lunde Esther Verburg Morten Eriksen Ole M. Sejersted 《The Journal of physiology》2002,540(2):571-580
We hypothesized that in congestive heart failure (CHF) slow-twitch but not fast-twitch muscles exhibit decreased fatigue resistance in the sense of accelerated reduction of muscle force during activity. Experiments were carried out on anaesthetized rats 6 weeks after induction of myocardial infarction or a sham operation (Sham). Animals with left ventricular end-diastolic pressure (LVEDP) > 15 mmHg under anaesthesia were selected for the CHF group. There was no muscle atrophy in CHF. Force generation by in situ perfused soleus (Sol) or extensor digitorum longus (EDL) muscles was recorded during stimulation (trains at 5 Hz for 6 s (Sol) or 10 Hz for 1.5 s (EDL) at 10 or 2.5 s intervals, respectively) for 1 h in Sol and 10 min in EDL at 37 °C. Initial force was almost the same in Sol from CHF and Sham rats, but relaxation was slower in CHF. Relaxation times (95–5 % of peak force) were 177 ± 55 and 131 ± 44 ms in CHF and Sham, respectively, following the first stimulation train. After 2 min of stimulation the muscles transiently became slower and maximum relaxation times were 264 ± 71 and 220 ± 45 ms in CHF and Sham, respectively ( P < 0.05 ). After 60 min they recovered to 204 ± 60 and 122 ± 55 ms in CHF and Sham, respectively ( P < 0.05 ). In CHF but not in Sham rats the force of contraction of Sol declined from the second to the sixtieth minute to 70 % of peak force. The EDL of both CHF and Sham fatigued to 24–28 % of initial force, but no differences in contractility pattern were detected. Thus, slow-twitch muscle is severely affected in CHF by slower than normal relaxation and significantly reduced fatigue resistance, which may explain the sensation of both muscle stiffness and fatigue in CHF patients. 相似文献
5.
6.
S. H. Sindrup L. Arendt-Nielsen K. Brøsen P. Bjerring H. R. Angelo B. Eriksen L. F. Gram 《European journal of clinical pharmacology》1992,42(6):587-591
Summary We have studied the hypoalgesic effect of codeine (100 mg) after blocking the hepatic O-demethylation of codeine to morphine via the sparteine oxygenase (CYP2D6) by quinidine (200 mg). The study was performed in 16 extensive metabolizers of sparteine, using a double-blind, randomized, four-way, cross-over design. The treatments given at 3 h intervals during the four sessions were placebo/placebo, quinidine/placebo, placebo/codeine, and quinidine/codeine. We measured pin-prick pain and pain tolerance thresholds to high energy argon laser stimuli before and 1, 2, and 3 h after codeine or placebo.After codeine and placebo, the peak plasma concentration of morphine was 6–62 (median 18) nmol·.l–1. When quinidine pre-treatment was given, no morphine could be detected (<4 nmol·l–1) after codeine. The pin-prick pain thresholds were significantly increased after placebo/codeine, but not after quinidine/codeine compared with placebo/placebo. Both placebo/codeine and quinidine/codeine increased pain tolerance thresholds significantly. Quinidine/codeine and quinidine/placebo did not differ significantly for either pin-prick or tolerance pain thresholds.These results are compatible with local CYP2D6 mediated formation of morphine in the brain, not being blocked by quinidine. Alternatively, a hypoalgesic effect of quinidine might have confounded the results. 相似文献
7.
Reversal of postmenopausal vertebral bone loss by oestrogen and progestogen: a double blind placebo controlled study 总被引:3,自引:0,他引:3
N Munk-Jensen S Pors Nielsen E B Obel P Bonne Eriksen 《British medical journal (Clinical research ed.)》1988,296(6630):1150-1152
Because of uncertainty about the place of hormones in the treatment of postmenopausal bone loss vertebral and forearm bone loss was measured by absorptiometry in early postmenopausal women before and after continuous or sequential treatment with combined oestrogen and progestogen in a double blind placebo controlled trial. Treatment with hormones significantly reversed the vertebral bone loss. The net gain in vertebral bone density amounted to 6.4% a year with continuous supplementation and 5.4% a year with sequential supplementation; the net gain in forearm bone density was lower (3.6% with continuous and 3.7% with sequential supplementation). Before a policy of supplementation with hormones can be recommended to all postmenopausal women with the aim of reducing the incidence of vertebral crush fractures further studies with different doses and combinations of hormones, administered over several years, are needed. 相似文献
8.
Patients underwent intracapsular cataract extraction and implantation of a Choyce Mk IX anterior chamber intraocular lens. At fluorescein angiography (FAG) at a mean of 8 months post-operatively, 9 showed leaking from the iridal vessels, and 3 were normal: Three cases were excluded because of factors affecting the iris FAG. At a mean of 37 months 5 still had a slight degree of leakage. No primarily negative iris FAG changed to positive later. Fluorescein gonioscopic photography (FGP) revealed leakage in 29.5% of the tips of the foot plates at a mean of 37 months. No correlation was observable between FGP and gonioscopy. The pupillary deformation quotient DQ (greatest: smallest pupillary diameter) was significantly greater at a mean of 8 months in the eyes with leakage in iris FAG than in eyes without leakage (P = 0.0145). Individually a change both in direction against normalisation and in elongation was recorded during the observation time. 相似文献
9.
10.