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1.
MR compatibility of Guglielmi detachable coils   总被引:6,自引:0,他引:6  
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2.
Fragestellung: Die Karzinomassoziierte Retinopathie (CAR) stellt ein seltenes paraneoplastisches Syndrom dar, das bislang am h?ufigsten bei kleinzelligen Bronchialkarzinomen beschrieben wurde. Wir berichten über 3 Patientinnen mit CAR in Gegenwart eines Mammakarzinoms bzw. eines Karzinoids der Cervix uteri. Patienten und Methode: Es wurden biomikroskopische, perimetrische, angiographische und elektrophysiologische Befunde erhoben. Au?erdem erfolgte eine Testung der Immunreaktivit?t der Seren an humaner Retina. Ergebnisse: Die Befunde umfa?ten ringf?rmige Gesichtsfelddefekte mit statokinetischer Dissoziation und eine pathologische St?bchen- und Zapfenantwort im ERG. Bei 1 Patientin wurde immunhistochemisch eine Reaktion im Bereich der Photorezeptorinnensegmente, der ?u?eren K?rnerschicht sowie der ?u?eren plexiformen Schicht bei fehlendem Nachweis von Antik?rpern gegen Recoverin gefunden. Diskussion: Neben dem kleinzelligen Bronchialkarzinom k?nnen auch andere Prim?rtumoren mit einer CAR vergesellschaftet sein. Der Nachweis von retinalen Autoantik?rpern unterstützt die Annahme einer tumorinduzierten Immunantwort aufgrund der Expression identischer Epitope durch die Tumorzellen. Dabei kommen offensichtlich verschiedene retinale Proteine als Autoantigene in Betracht.   相似文献   
3.
Adverse reaction to intravenous gadoteridol   总被引:1,自引:0,他引:1  
  相似文献   
4.
Purpose: To flatten pigment epithelial detachments (PED) cue to age-related macular degeneration in an attempt to visualize the underlying choroidal neovascularization by fluorescein angiography (FA) and reveal a treatment target. Methods: Nine patients with PED received intravitreal gas injections via the pars plana and postured face down. Fluorescein angiograms were obtained before and after gas injection. In two patients, retinal scotopic sensitivity was also measured. Results: Eight patients demonstrated change in the shape and size of the PED following gas injection. Four patients showed a better delineation of underlying structures on FA. Three patients had focal laser treatment to the newly visible choroidal neovascular complex, but this was successful in only one patient with flattening of the PED. Conclusion: Pigment epithelial detachments can be modified by intravitreal gas injection in some patients, but this treatment did not have a major impact on overall outcome or management.  相似文献   
5.
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   
6.
Cell physiology of cAMP sensor Epac   总被引:9,自引:0,他引:9  
Many animal studies and human epidemiological findings have shown that impaired growth in utero is associated with physiological abnormalities in later life and have linked this to tissue programming during suboptimal intrauterine conditions at critical periods of development. However, few of these studies have considered the contribution of the placenta to the ensuing adult phenotype. In mammals, the major determinant of intrauterine growth is the placental nutrient supply, which, in turn, depends on the size, morphology, blood supply and transporter abundance of the placenta and on synthesis and metabolism of nutrients and hormones by the uteroplacental tissues. This review examines the regulation of placental nutrient transfer capacity and the potential programming effects of nutrition and glucocorticoid over-exposure on placental phenotype with particular emphasis on the role of the Igf2 gene in these processes.  相似文献   
7.
8.
Dihydropyridine (DHP) calcium channel antagonists, which inhibit the slowly inactivating or L-type cardiac calcium (Ca) current, have been shown to be ineffective in blocking45Ca influx and Ca-dependent secretion in a number of neuronal preparations. In the studies reported here, however, the antagonist DHP nifedipine inhibited both the L-type Ca current and potassium-evoked substance P (SP) release from embryonic chick dorsal root ganglion (DRG) neurons. These results suggest that, in DRG neurons. Ca entry through L-type channels is critical to the control of secretion. The inhibition of Ca current by nifedipine was both voltage and time-dependent, significant effects being observed only on currents evoked from relatively positive holding potentials maintained for several seconds. As expected from these results, nifedipine failed to inhibit L-type Ca current underlying the brief plateau phase of the action potential generated from the cell's normal resting potential; likewise, no significant effect of the drug was observed on action potential-stimulated SP release evoked by electrical field stimulation. The results of this work are discussed in terms of an assessment of the role of L-type Ca channels in neurosecretion.This work was supported by United States Public Health Service Grant NS16483 (KD) and by a USPHS Postdoctoral Fellowship (SGR)  相似文献   
9.
Clark  P.  Holz  P.  Booth  R.  Jakob-Hoff  R.  Cooper  D.W.  Boardman  W.S.  Parry  B.W.  Norman  R.J. 《Comparative clinical pathology》2003,12(1):11-16
 Blood was collected from 31 Parma wallabies from five different captive populations. The morphology of erythrocytes, leucocytes and platelets was similar to that previously described for macropodids. The effects of location (population), anaesthesia and analyser on the haematological characteristics of the wallabies were considered. Location had an affect on many of the values, anaesthesia affected some of the leucocyte values, and analyser had little effect. Received: 22 November 2002 / Accepted 13 February 2003 Acknowledgements We thank Mrs R. Power, Ms S. Bayliss, Ms T. Smith and Mrs P. Slack for technical assistance, Mr D. Hopcroft for assistance with electron microscopy and Mr D. Hedderly for performing the statistical analyses.  相似文献   
10.
MR elastography is a novel imaging technique for the visualization of elastic properties of tissue. It is expected that this method will have diagnostic value for the clarification of suspicious breast lesions. Low-frequency mechanical waves are coupled into the tissue and visualized via an MR sequence which is phase-locked to the mechanical excitation. Commonly, elasticity is assumed to be isotropic and reconstruction is performed in only two dimensions. The technique is extended to three dimensions such that the entire symmetric elasticity tensor is assessed. This is achieved by measuring different phases of the mechanical wave during one oscillatory cycle. Thereby it is possible to provide information about the anisotropy of the elasticity tensor. Finite-element simulations as well as phantom experiments are performed to demonstrate the feasibility of the method. Initial clinical results of a breast carcinoma are presented. The analysis of the eigenvalues of the elasticity tensor support the hypothesis that breast carcinoma might exhibit an anisotropic elasticity distribution. The surrounding benign tissue appears isotropic. Thereby new and additional diagnostic information is provided which might help in distinguishing between benign and malignant breast diseases.  相似文献   
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