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1.
J D Oosting R H Derksen T M Hackeng M van Vliet K T Preissner B N Bouma P G de Groot 《Thrombosis and haemostasis》1991,66(6):666-671
The effect of sera and purified IgG isolated from plasma of 46 patients with systemic lupus erythematosus (SLE) and 9 healthy donors on the endothelial cell (EC) mediated protein C activation was investigated. Out of the 46 SLE sera used, 19 were antiphospholipid antibodies (aPL) positive. From 12 patients IgG was isolated, of which 6 contained aPL. EC were first incubated with IgG (7 mg/ml) or serum (1:1 diluted) for 1 h and then tested for their ability to promote protein C activation by thrombin, with the cells either in a monolayer or in a suspension. The normal range (mean of control values +/- 2 SD) of protein C activation was 80-120%. In contrast to others, we could not detect an inhibition of protein C activation by any of the patient IgG's or sera. The recently described cofactor for binding of antiphospholipid antibodies to phospholipids, beta 2-glycoprotein I, was purified and added to the purified IgG's. A combination of these two components did not inhibit the EC mediated protein C activation by thrombin. This study suggests that the inhibition of the protein C activation, mediated by EC, is not a general mechanism by which aPL related thrombosis can be explained. 相似文献
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Paramagnetic macrocyclic chelates show promise as magnetic resonance (MR) imaging contrast agents due to stability and relaxivity comparable to those of DTPA-type chelates. For the three copper and manganese macrocyclic complexes studied in aqueous solution, T1 and T2 relaxivities ranged from 0.14 to 5.88 mM-1sec-1 at 6.25 MHz. In rats, the intravenous administration of 16 mumol/kg of Mn(cyclam) caused the liver T1 relaxation rate to double at 15 minutes after injection. T1 measurements by pulsed MR imaging and manganese analyses on excised tissue showed that both relaxation rate (1/T1) and manganese content of liver and kidney increase linearly with the dosage of Mn(cyclam). The linear relationship between 1/T1 and manganese content can be considered an "in tissue" relaxivity plot for the agent. The resulting relaxivity is 54 mM-1sec-1 in liver, compared with 3.1 mM-1sec-1 in aqueous solution. Although this work is preliminary, the implication for medical MR imaging applications is that macrocyclic contrast agents can be effective at approximately one-tenth the current typical dose used for gadolinium DTPA. 相似文献
4.
Summary Based upon findings from 60 cadavers (120 sides), the incidence of superior laryngeal nerve loop, connecting the cervical sympathetic chain and the superior laryngeal nerve and its branches, the external and internal laryngeal nerve, was 98.3% (118 out of 120 sides). In most cases the loop connected the sympathetic chain and the external laryngeal nerve. The external laryngeal nerve was looped, and not linear as traditionally thought. The loop could be divided into three categories, V-shaped, U-shaped and mixed, and subdivided into 5 types and 17 subtypes according to morphological variation. The loop without exception innervated not only the cricothyroid muscle, but also the thyroid gland. The loop is one of the origins of the thyroid nerve. It seems that for thyroid surgery the loop, when lower in position, should be carefully separated from the superior thyroid vessels before the latter are ligated, in order to preserve a normal nerve supply to the muscle as well as to the part of the gland that remains after surgery.
L'anse du nerf larynge supérieur, étude anatomique et applications chirurgicales
Résumé La fréquence d'une anse du nerf laryngé supérieur réalisant une anastomose entre la chaine sympathique cervicale et le nerf laryngé supérieur et/ou ses branches (rameau laryngé externe et ingerne), est de 98,3 % (118/120). Ce résultat s'appuie sur l'étude de 60 cadavres. Dans la plupart des cas, l'anastomose se fait entre la chaine sympathique cervicale et le rameau laryngé externe. Ce rameau laryngé externe a un trajet curviligne et non linéaire conformément aux données classiques. Il existe trois catégories d'anses : en "V", en "U" et mixte ; on peut également les subdiviser en 5 types et 17 sous-types en fonction des variations morphologiques. Cette anse innerve constamment non seulement le muscle cricothyroïdien mais aussi la glande thyroïde dont elle fournit une partie de l'innervation. Lors de la chirurgie thyroïdienne, si l'anse est en position basse, les nerfs doivent être soigneusement disséqués et séparés des vaisseaux thyroïdiens supérieurs avant ligature de ces derniers de façon à conserver l'innervation normale du muscle et de la partie restante de la glande.相似文献
5.
0 引言 我科 1996 / 1998分别应用消痔灵与强的松龙混合液、消痔灵液、强的松龙液行鼻息肉内 ,鼻息肉蒂部注射治疗鼻息肉各 5 0例 ,并设对照组为鼻腔滴入及口服类固醇激素 5 0例 ,合计 2 0 0例 ,观察并对比其疗效 .1 对象和方法1.1 对象 男 12 8例 ,女 72例 ,年龄 8~ 78(平均 38)岁 ,病程 32 a~ 45 (平均 4.5 ) a.其中在本次治疗前做过一次鼻息肉摘除术后复发的 2 7例 ,做过 2次或 2次以上手术的 12例 .主要症状为鼻塞、流脓涕、头痛及嗅觉减退 .全部病例治疗前均行鼻窦 X线拍片 ,其中上颌窦炎 12 5例、筛窦炎 5 8例、蝶窦炎 2例、… 相似文献
6.
Diminished effect of etidronate in vitamin D deficient osteopenic postmenopausal women 总被引:7,自引:0,他引:7
J. C. Koster W. H. L. Hackeng H. Mulder 《European journal of clinical pharmacology》1996,51(2):145-147
Objective: The effects of vitamin D deficiency in osteopenic postmenopausal women treated with intermittent cyclical etidronate have
been studied. Bone mass and biochemical parameters as bone markers were measured before and after one year of therapy with
intermittent cyclical etidronate.
Results:
In 30 patients without vitamin D deficiency, bone mass in the lumbal spine and femoral neck was significantly increased compared
to 28 vitamin D deficient patients. After cyclical intermittent etidronate therapy, serum osteocalcin and PTH were significantly
increased in the vitamin D deficient patients, whereas in non-vitamin D deficient patients they did not change.
Conclusion:
It is worthwhile measuring serum vitamin D before starting etidronate therapy and, in case of deficiency, to give vitamin
D.
Received: 6 April 1995/Accepted in revised form: 23 April 1996 相似文献
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9.
Calcium supplementation reduces vertebral bone loss in perimenopausal women: a controlled trial in 248 women between 46 and 55 years of age 总被引:5,自引:0,他引:5
P J Elders J C Netelenbos P Lips F C van Ginkel E Khoe O R Leeuwenkamp W H Hackeng P F van der Stelt 《The Journal of clinical endocrinology and metabolism》1991,73(3):533-540
To study the effect of calcium supplementation on perimenopausal bone loss, 295 women were randomized into a control group and 2 supplementation groups receiving, respectively, 1000 and 2000 mg elemental calcium/day for a period of 2 yr. We observed a significant decrease in lumbar bone loss in relation to the calcium supplementation (mean loss after 2 yr of 3.5% in the control group vs. 1.3% and 0.7% in the 1000 and 2000 mg groups, respectively), a significant increase in urinary calcium excretion, and a significant decrease in the urinary hydroxyproline/creatine ratio, serum alkaline phosphatase, osteocalcin, and 1,25-dihydroxyvitamin D. The effect of calcium supplementation on lumbar bone loss was significant in the first year of supplementation, but not in the second. However, the urinary hydroxyproline/creatinine ratio and the serum alkaline phosphatase level remained significantly decreased in the treatment groups at the end of the study; this was not the case for serum osteocalcin. Calcium supplementation did not have a significant effect on metacarpal cortical bone loss. The difference in biochemical parameters between the 2 supplementation groups was small. No significant interaction was observed between the menopausal status of the subjects and the effect of calcium supplementation. We conclude that calcium supplementation retards lumbar bone loss in the first year of calcium supplementation by reducing bone turnover. However, the effect on lumbar bone loss over a longer time span is still uncertain. 相似文献
10.
Tom De Beule T Boulanger S Heye WJ van Rooij WH van Zwam L Stockx 《Interventional neuroradiology》2021,27(1):51
Background and purposeFlow diverters are increasingly used to treat intracranial aneurysms. We report the safety and efficacy of the p64 flow diverter, a resheathable and detachable device for intracranial aneurysms.Materials and methodsWe retrospectively reviewed 108 patients with 109 aneurysms treated with the p64 between March 2014 and July 2019. There were 87 women and 21 men, mean age 57 years. Of 109 aneurysms, 74 were discovered incidentally, 12 were symptomatic, 18 were previously treated, and five were ruptured dissection aneurysms. A total of 10 aneurysms were located in the posterior circulation. The mean aneurysm or remnant size was 8.1 mm.ResultsHemorrhage by perforation with the distal guidewire occurred in two patients with permanent neurological deficits in one. In one patient, acute in-stent occlusion caused infarction with a permanent deficit. Permanent morbidity was 1.9% (2 of 108, 95%CI 0.1–6.9%); there was no mortality. During follow-up, three in-stent occlusions occurred, all asymptomatic. There were no delayed hemorrhagic complications. At six months, 77 of 96 aneurysms (80.2%) were completely occluded, and at last follow-up, this increased to 93 of 96 aneurysms (96.9%). In-stent stenosis at any degree occurred in 11 patients, progressing to asymptomatic complete occlusion in one. In the other patients, stenosis resolved or improved at further follow-up.ConclusionThe p64 offers an effective and safe treatment option. Aneurysm occlusion rate was 97% at last follow-up, mostly achieved with a single device. There were no delayed hemorrhagic complications. Delayed in-stent stenosis infrequently progresses to occlusion but remains a matter of concern. 相似文献