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21.
The number of cataract extractions in Switzerland has tripled since 1981. In 1986, a total of 15,500 cataract operations were performed, 95% of which were accompanied by an intraocular lens implantation. In spite of this tremendous increase pseudophakic bullous keratopathy remains a rare indication for keratoplasties: between 1980 and 1986 only 20 grafts were performed at the authors' clinic for irreversible corneal edema following lens implantation. After implantation of posterior chamber lenses, penetrating keratoplasty for corneal decompensation is performed after a significantly shorter period (one year) than with anterior chamber lenses (three years), or in iris-supported lenses (four years). In Switzerland, the incidence of pseudophakic bullous keratopathy among patients with posterior chamber lenses is around 0.1 to 0.3%. A long-term investigation of the endothelial cell density over a period of seven years in 16 patients with a Binkhorst two-loop lens revealed a quite stable and satisfactory cell density of 1600 cells/mm2. 相似文献
22.
K. Norpoth W. Stücker E. Krewet G. Müller 《International archives of occupational and environmental health》1988,60(3):163-168
Summary From preliminary experiments it was known that radiolabelled benzene and some of its metabolites during its metabolic activation process produce different in vitro DNA-phenyladducts in mitoplasts [5, 11].As we reported previously [9] at least one of these adducts, N-7-phenylguanine, is excreted in the urine of rats in measurable amounts, probably through an excision-repair mechanism after an inhalation experiment. Now we found, after i.p. application of benzene in the urine of rats, a compound separated by cation-exchange chromatography that behaves like a synthezised N-7-phenylguanine reference substance with respect to its retention index and the UV-absorption. This finding could be confirmed by HPLC-measurements with reversed-phase carrier materials. Silylation and gaschromatographic/mass spectrometric (GC/MS) separation of the fraction, which contains the phenylguanine, revealed that these fractions contain further phenyl adducts. Furthermore we studied the time-dependent excretion of the DNA-base adduct. Surprisingly the excretion dropped to zero on the fourth day and showed a new increase thereafter. 相似文献
23.
A representative sample of 800 patients was taken from 15,000 children treated between 1972 and 1984 in the Department of Pediatric Ophthalmology of Frankfurt University Eye Hospital. Their charts were reviewed to answer two questions: what are the most frequent reasons for ophthalmological examination in children under 15 years old and what are the most frequent diagnoses? Ophthalmological examinations were most frequently scheduled because of strabismus, errors of refraction and trauma or inflammation of the anterior segment, though also in a large number of cases because of general diseases, most often neurologic diseases such as epilepsy or elevated intracerebral pressure. The diseases diagnosed ophthalmologically were classified as congenital or acquired eye diseases and congenital or acquired general diseases with ocular symptoms. The most frequent are indicated in the text. Acquired diseases were more frequent than congenital diseases, though this group proved to be much larger in pediatric patients than in adult patients. 相似文献
24.
25.
F St?hlberg A Ericsson B Nordell C Thomsen O Henriksen B R Persson 《Acta radiologica (Stockholm, Sweden : 1987)》1992,33(3):179-200
The present work is intended as a nonmathematical review of the role of flow and motion in nuclear magnetic resonance (MR) imaging. A historical review of MR flow measurement techniques is given, followed by a short overview of flow models in vitro and in vivo. The theory behind the influence of motion on the modulus and phase MR signal information is discussed and effects such as washin/washout, flow-induced signal void, phase offset, and phase dispersion are defined. A simple approach to the concept of MR angiography is given, and methods for quantitative flow measurements such as the phase mapping technique, are surveyed. Aspects of the measurement of diffusion and microcirculation are given, and finally, an overview of the role of MR flow imaging in present and future clinical application is given. 相似文献
26.
S. Störkel 《Der Urologe. Ausg. A》2004,43(3):118-119
27.
28.
Dr. K. Hekmat Dr. A. Kröner Dr. H. Stützer Prof. Dr. R. H. G. Schwinger PD Dr. S. Kampe Prof. Dr. G. B. W. E. Bennink Prof. Dr. U. Mehlhorn 《Zeitschrift für Herz-, Thorax- und Gef??chirurgie》2004,18(6):257-267
Zusammenfassung
Einleitung:
Das Ziel dieser Studie war die Entwicklung eines spezifischen Schweregradklassifizierungssystems für die Beurteilung und Vorhersage von Organfunktionsstörungen und Überleben bei herzchirurgischen Intensivpatienten.
Methoden:
Hierzu wurden konsekutiv alle erwachsenen Patienten nach einem herzchirurgischen Eingriff unter Einsatz der Herzlungenmaschine über einen Zeitraum von 3 Jahren in die Studie aufgenommen. Im Konstruktionsset erfolgte die Auswahl der Variablen mit Hilfe der Patienten, die mindestens 24 Stunden auf der Intensivstation verbrachten. Die Ergebnisse wurden dann in zwei Validierungssets mit allen Intensivpatienten überprüft. Die Qualität des Scores wurde mit dem Hosmer-Lemeshow-Test (HL) sowie der ROC-Analyse beurteilt, und mit dem APACHE-II- und dem MODS-Score verglichen.
Ergebnisse:
Insgesamt wurden 3230 Patienten über einen Zeitraum von 3 Jahren auf unserer Intensivstation aufgenommen. Die HL-Werte für den neuen Score waren 5,8 (APACHE-II: 11,3; MODS: 9,7) für das Konstruktionsset, 7,2 (APACHE-II: 8,0; MODS: 4,5) für das Validierungsset I und 5,9 für das Validierungsset II. Die Fläche unter der ROC-Kurve war 0,91 (APACHE-II: 0,86; MODS: 0,84) für den neuen Score im Konstruktionsset, 0,88 (APACHE-II: 0,84; MODS: 0,84) in dem Validierungsset I, und 0,92 in dem Validierungsset II.
Schlussfolgerung:
Der neue CASUS (Cardiac Surgery Score) zeigt für herzchirurgische Intensivpatienten eine exzellente Kalibrierung und Diskriminierung bezüglich der 30-Tage-Letalität. Die Variablen des CASUS sind einfach, reproduzierbar und werden routinemäßig in herzchirurgischen Intensivstationen erfasst. Der CASUS könnte als Expertensystem für das Diagnostizieren von Organfunktionsstörungen, der Entscheidungsfindung, der Ressourcenauswertung und Vorhersage der Letalität für herzchirurgische Intensivpatienten dienen. 相似文献
29.
Anjali Shah Eric Eggenberger Robert Zivadinov Olaf Stüve Elliot M. Frohman 《Neurotherapeutics》2007,4(4):627-632
Physicians who treat multiple sclerosis (MS) face the challenge of patients exhibiting ongoing disease activity, including
exacerbations, loss of functional capabilities, intellectual decline, and radiologic progression, despite being on a disease-modifying
agent (DMA). After searching for factors that might at least in part explain these changes—such as nonadherent drug-taking
behavior, or the presence of interfer-on-neutralizing antibodies—some providers may ultimately decide to switch the patient
to another DMA. In most circumstances, patients likely derive only partial effects from these agents, even in the absence
of compromising factors. Thus, a number of factors must be considered in order to intensify the treatment regimen in response
to disease progression. In the context of an inadequate treatment response to a DMA, some clinicians will convert the patient
to an alternative therapy, and others will instead use a second agent in combination with the first (the so-called platform
agent). In the first of this two-part series, we explored the use of anti-inflammatory CS and ACTH to treat MS exacerbations.
Although we underscored the limited availability of evidence-based studies to support specific regimens for this purpose,
there is an even greater paucity of data to support the routine use of these agents in order to achieve chronic disease-modifying
effects in those who continue to deteriorate clinically, radiographically, or both. Without doubt, a number of factors influence
the formulation of combination treatment plan for MS. Nevertheless, we will focus on the rationale and practical schemes that
can be considered for using corticosteroids (CS) (and perhaps even ACTH) in an attempt to modify various domains of ongoing
disease activity. 相似文献
30.
PD Dr. S. Ständer 《Der Hautarzt; Zeitschrift für Dermatologie, Venerologie, und verwandte Gebiete》2007,58(7):627-638
Chronic pruritus (starting from 6 weeks duration) is symptom of dermatological, internal, neurological or psychiatric disease. Identification and treatment of the underlying diseases is of great importance especially in the initial phase of chronic pruritus in order to prevent peripheral and central sensitization processes and thus chronification. Application of the redefined clinical classification, newly defined clinical algorithms and inquiry of clinical characteristics of pruritus is helpful in finding the underlying disease. In chronic pruritus existing for several years, clarifying the underlying origin is difficult and therapies are often ineffective. Next to conventional therapies such as antihistamines and corticosteroids, central effective substances can be applied preventing pruritus sensation on spinal or cerebral level. 相似文献