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排序方式: 共有783条查询结果,搜索用时 15 毫秒
1.
MR compatibility of Guglielmi detachable coils   总被引:6,自引:0,他引:6  
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Adverse reaction to intravenous gadoteridol   总被引:1,自引:0,他引:1  
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4.
The present study completed a previous randomized trial that demonstrated the protective effect of 1-year psoas training on lumbar bone loss in postmenopausal women. Computerized tomography had been carried out at the beginning (CT1) and at the end (CT2) of this trial. In the present study, 67 women having completed the first trial were asked to practice psoas exercises (60 hip flexions in sitting position with a 5 kg weight on the knee) for 2 additional years with a third CT control at the end of this period (CT3). The aim of this complementary study was to assess the compliance rate and long-term effect on bone of daily psoas muscle training over a longer period. Twenty-one women performed this daily psoas training for 3 years from CT1 to CT3, and 14 acted as controls during the same period. Fourteen women were controls during the first year (from CT1 to CT2) but practiced psoas training during the following 2 years (from CT2 to CT3). Four women were psoas trained during the first year (from CT1 to CT2) and subsequently crossed over to the control group for the last 2 years. The compliance rate was 42%, with an attendance rate of 88%. The lumbar bone loss was lower in the 21 women trained over the 3 years (−3.26 ± 28.45 mg/cm3) than in the 14 untrained women (−16.79 ± 8.51 mg/cm3) (P= 0.02). The bone loss was not significantly reduced between the two periods of the study in the 12 women having been controls from CT1 to CT2 and having crossed over to the active training group from CT2 to CT3. Psoas training may be effective against lumbar bone loss. We conclude that specific training may play a contributing role in the preventive strategy to avoid osteoporosis. Received: 23 February 1996 / Accepted: 25 October 1996  相似文献   
5.
Two nitroxide spin labels (NSL) were compared for in vitro relaxivity and in normal rats for efficiency of urographic enhancement. One of the NSL, PCA, a pyrrolidinyl agent, was ionic and one, NAT, was a non-ionic pyrrolidinyl NSL with multiple hydroxyl substituents for water solubility. Using both NSLs the renal medulla and papilla were noted to show greater contrast enhancement than the cortex, with a maximum enhancing effect between 5 and 15 minutes. Using doses of 1.0 and 2.5 mmol/kg, more than 100 per cent increases in spin echo intensities above the baseline were observed. The lowest tested dose of 0.1 mmol/kg showed an easily detectable enhancing effect for NAT. The good contrast enhancing properties of NAT, considered together with its better acute tolerance, justifies further investigation of this non-ionic compound.  相似文献   
6.
Patellofemoral joint: kinematic MR imaging to assess tracking abnormalities   总被引:4,自引:0,他引:4  
Shellock  FG; Mink  JH; Fox  JM 《Radiology》1988,168(2):551-553
The patellofemoral joint was imaged with magnetic resonance (MR) in the axial plane while the knee was positioned from 0 degrees to 32 degrees of flexion (nine positions). These multiple sequential images obtained within the early phases of flexion of the knee were viewed in a "cine-loop" format, producing a kinematic study that clearly demonstrated the relationship of the patella to the trochlear groove. Four healthy subjects and one patient with known bilateral subluxing patellae were studied. The preliminary results suggest that kinematic MR imaging of the patellofemoral joint is potentially useful for the evaluation of patellar tracking abnormalities.  相似文献   
7.
Summary Monkey interferon (MKIF) produced in monkey BSC-1 cells infected with Newcastle disease virus showed antiviral activity on human foreskin fibroblasts and RD114 cells—a human line transformed by feline sarcoma virus. The titer of the monkey interferon in human cells was 10–30 fold greater than that found in several normal monkey (BSC-1, CV-1) or SV40 transformed (C2, C6, T-22) monkey cell lines tested. Ten to fifteen-fold purification of MKIF without loss of activity could be achieved by chromatography on Phenyl-Sepharose CL-4B. Antiviral activity of MKIF was fully resistant to treatment with 1 per cent sodium dodecyl sulfate (SDS).With 1 Figure  相似文献   
8.
Summary Biomechanical models of the cervical spine require knowledge of the position, size and orientation of the individual muscles that act on the cervical spine. We have developed a technique to stereometrically measure anatomical specimens. The apparatus is composed of three graduated metallic rods, which slide along a fixed support. This method is accurate to map the anatomy of individual muscles and provides quantitative data on their lines of action. Results are obtained from one specimen. The computer processing of the collected data allows formulation of a three-dimensional model of the neck muscles in man.
Méthode d'étude anatomique quantitative des muscles de la nuqueEtude préliminaire
Résumé Pour élaborer un modèle biomécanique de la colonne cervicale, il faut connaître la position, la taille et l'orientation des différents muscles du cou. Nous avons mis au point une méthode de mesure stéréométrique sur des sujets anatomiques. L'appareil est composé de 3 axes métalliques gradués qui coulissent sur un support fixe. Cette technique permet une étude anatomique précise de chacun des muscles de la nuque, fournissant des données quantitatives sur les différents faisceaux ou lignes d'action. Les résultats sont obtenus sur un sujet. Leur traitement informatique permettra l'élaboration d'un modèle mathématique tridimensionnel des muscles du cou chez l'homme.
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9.
D,L-4-(3,4-Dichloro-benzoylamino)-5-(N-3-methoxypropyl- pentylamino)-5-oxo-pentanoic acid (CR 1505) belongs to a newly discovered class of agents with cholecystokinin (CCK) antagonistic activity. CR 1505 displaces CCK-8 from the central CCK receptors at concentrations of 9.1 mumol/l, and from the peripheral CCK receptors at concentrations of 0.33 mumol/l. CR 1505 antagonizes in vitro the contractant effects of CCK-8 on gall bladder strips of the guinea pig at 0.79 mumol/l and those on the small intestine at 1.6 mumol/l. These antagonistic effects are dose dependent and of competitive type. The antagonistic activities of CR 1505 against contractions of smooth muscles elicited by CCK-8 are at least 1000 times more potent than those against the contractions elicited by acetylcholine, BaCl2, histamine, serotonin, Substance P, bradykinin or dimethylphenylpiperazine. CR 1505 is also practically ineffective against the contractions of the small intestine of the guinea pig elicited by electrical field stimulations either as "cholinergic twich" (0.05 Hz), or as "cholinergic contractions" (trains of 10 min at 1 Hz), or as "non-cholinergic contractions" (200 impulses at 5 Hz in presence of atropine). CR 1505 is therefore a potent, specific, competitive and reversible CCK antagonist.  相似文献   
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