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91.
Fragestellung: Orbitotomien nehmen innerhalb der Ophthalmochirurgie auf Grund der involvierten anatomischen Strukturen und des daraus resultierenden Spektrums m?glicher perioperativer Probleme eine Sonderstellung ein. Um einen überblick über die Art und H?ufigkeit intra- und postoperativer Probleme bei Orbitotomien zu erhalten, führten wir eine retrospektive Auswertung an unserer Klinik durchgeführter Orbitotomien durch. Patienten und Methode: Es wurden 48 Orbitotomien bei 46 Patienten berücksichtigt, die zwischen 08/1995 und 02/1998 operiert wurden. Ergebnisse: Schwerwiegende intraoperative Komplikationen waren mit zwei transfusionspflichtigen Blutungen und einer Liquorfistel selten. Sie wurden interdisziplin?r behandelt. Postoperativ traten vorübergehende funktionelle St?rungen mit guter Rückbildungstendenz wie Visusminderungen (35 %), Motilit?tsst?rungen mit oder ohne Doppelbildwahrnehmung (20 %) und Lidfehlstellungen auf. Ihnen liegt v. a. die postoperative ?dem- und H?matombildung zugrunde. Persistierende Funktionseinschr?nkungen waren dagegen selten (10 %). Schlu?folgerung: Unsere Untersuchung zeigt, da? perioperativ bei Orbitotomien v. a. vorübergehende funktionelle Einschr?nkungen auftreten, die sich rasch zurückbilden. Schwere Komplikationen sind dagegen selten, treten v. a. intraoperativ auf und k?nnen eine interdisziplin?re Therapie erfordern.   相似文献   
92.
93.
As several reinjection procedures have shown encouraging results in terms of imaging, we investigated whether the kinetics of thallium-201 would differ between the standard stress-redistribution-reinjection approach and the stress-immediate reinjection approach. In 53 consecutive patients with undiagnosed chest pain, 75 MBq (2 mCi)201Tl was injected at maximal exercise. In 26 of these patients (group I), 37 MBq (1 mCi)201Tl was reinjected immediately after completing the exercise images (the immediate reinjection procedure) and in 27 patients (group II), 37 MBq (1 mCi)201Tl was reinjected after completing 3-h redistribution images (the standard reinjection procedure). Mean peak201Tl blood activity after exercise was 17.7±12.5 kBq/ml (4.8±3.4 mCi/ml) for group I versus 16.4±9.2 kBq/ml (4.4±2.5 mCi/ml) for group II (NS). The relative increase in201Tl blood activity after reinjection of half the initial dose [37 MBq (1 mCi)] exceeded 50% of the initial peak in both groups. The relative amount of201Tl delivered to the myocardium was assessed by the area under the curve after both exercise and reinjection, and was 117%±72% for group I and 112%±73% for group II (NS). Blood clearance of201Tl was at least biexponential. Mean early decay constants (1) after exercise and reinjection were 0.30±0.18 min–1 and 0.22±0.046 min–1 respectively for group I (T 1/2 2.3 min and 3.2 min respectively, NS), and 0.30±0.12 min–1 and 0.24±0.07 min–1 respectively for group II (T 1/2 2.3 min and 2.9 min respectively, NS). For both procedures no significant differences were found between 1 after exercise and 1 after injection. The mean late clearance (2) from the blood was 0.032±0.056 min–1 and 0.012±0.012 min–1 respectively for group I (T 1/2 21.6 min and 57.7 min respectively, NS), and 0.036±0.030 min–1 and 0.014±0.014 min–1 respectively for group II (T 1/2 19.3 min and 49.5 min respectively, NS). Also, no significant differences were found between 2 after exercise for both groups and between 2 after reinjection for both groups. We conclude that reinjection of 37 MBq (1 mCi)201Tl (half the initial dose) results in a relative increase in the initial peak and a relative increase in the amount of201Tl delivered to the myocardium of more than 50% for both the standard and the immediate reinjection procedure. The clearance of201Tl from the blood was not influenced by exercise or by the time of reinjection. Based on201Tl kinetics as measured in the peripheral blood, there is no reason to postpone reinjection until 3–4 h following exercise.  相似文献   
94.
Cystic fibrosis (CF) is caused by mutations in the gene encodinga chloride channel called the CF transmembrane conductance regulator(CFTR). A single mutation in this gene, deletion of three nucleotidesthat leads to the absence of phenylalanine 508 (i.e., F508),is found on 70% of all CF chromosomes. To explore the molecularmechanism(s) responsible for defective chloride transport inpatients with CF, we have studied the processing, localization,and function of wild type (W.T.), F508 and G551D CFTR (a GDmissense mutation at position 551) in retrovirus transducedL cells. Cell transduced with W.T. CFTR expressed a 170 kd CFTRprotein that was endoglycosidase H (Endo H) resistant, localizedto the plasma membrane, and generated a cAMP-mediated anionconductance (GCl) when stimulated with standard concentrationsof forskolin (5 µM), cpt cAMP (400 µM) and IBMX(100 µM). The G551D CFTR was indistinguishable from W.T.CFTR with respect to post-translational processing and localization,but it did not produce a cAMP-activated GCI in response to thestandard stimulation cocktail. However, raising the IBMX concentrationto 4 mM produced Gc, in G551D expressing cells. Cells transducedwith F508 CFTR expressed an Endo H sensitive CFTR protein (140kd) that was found in a cytosolic, perinuclear location. Thesecells did not respond to the standard cocktail, but 20% of cellsincreased GCI when the cocktail contained 4 mM IBMX. Incubationof cells at 26°C for 48 hours prior to analysis elicitedresponses in F508 expressing cells at low IBMX concentrations,but had no effect on the responses of cells expressing W.T.or G551D CFTR. The response of F508 to 26°C was associatedwith plasma membrane localization of CFTR protein. These resultssuggest that there are two mechanisms whereby CFTR mutationslead to loss of cAMP-responsive GCI. First, shown by G551D CFTR,the protein can be processed and targeted to the plasma membranecorrectly, but lack full responsiveness to stimulation by cAMP.Second, as examplified by F508 CFTR, a partially functionalprotein which is not targeted to its correct cellular locationcan also lead to loss of the cAMP, responsive GCI.  相似文献   
95.
Unlike the days of Robert Koch when infectious diseases were the principal contributors to morbidity and mortality, today's illness and death are most often caused by noncommunicable diseases that have the special characteristics of resulting largely from one's own lifestyle, especially tobacco use and nutritional excesses. By listening to nature, we can detect and identify risk factors for various types of cancer, explore their mechanisms of action, and execute preventive strategies leading to their reduction or modification, thereby, decreasing the incidence and mortality of disease. An example of the role of metabolic overload in carcinogenesis is the impact of an excessive intake of dietary fat on the development and progression of breast cancer. For the general pathogenesis of cancer, the risks associated with metabolic overloads are contrasted with those of low-level exposures. To broaden the impact of preventive medicine beyond factorial nutritional education in Germany, we recommend that (a) every medical school have a department of preventive medicine with emphasis on epidemiology and health promotion, and (b) all schools beginning in first grade have a comprehensive school health education program coordinated by a fulltime health education teacher.
Zusammenfassung Zur Zeit von Robert Koch waren Infektionskrankheiten die Hauptverursacher der Morbidität und Mortalität; heute sind Krankheiten und Todesfälle vorwiegend durch nicht übertragbare Krankheiten verursacht. Charakteristisch für solche Krankheiten ist, dass sie die Konsequenz des eigenen Lebensstiles darstellen z.B. Tabakgebrauch, Fehlernährung. Indem wir in einem listening to nature auf die Signale unseres Körpers achten, können wir die Risikofaktoren für die verschiedenen Arten von Krebskrankheiten aufspüren und identifizieren und ihren Wirkungsmechanismus erforschen. Wir werden Strategien zur Prävention entwickeln können, die diese Risikofaktoren vermindern oder verändern und somit zur Senkung der Inzidenz und der Mortalitätsrate beitragen. Welche Rolle eine Stoffwechsel-Überbelastung im Krankheitsverlauf eines Karzinomes haben kann, zeigt das Beispiel einer übermässig fetthaltigen Ernährung auf die Entwicklung und den Krankheitsverlauf bei Brustkrebs. Zum Verlauf einer Krebskrankheit im allgemeinen lässt sich feststellen, dass jene Risikofaktoren, die mit einer Stoffwechselüberbelastung assoziiert sind, sich stark von solchen unterscheiden, welche Expositionen mit geringen Schadstoffmengen haben. Um in Deutschland den Einfluss der Präventivmedizin zu verstärken und zwar über eine Ausbildung in Ernährungslehre hinausgehend, empfehlen wir, dass a) jede medizinische Ausbildungsstätte eine Abteilung Präventivmedizin mit dem Schwerpunkt Epidemiologie und Gesundheitsförderung hat und dass b) alle Schulen vom ersten Schuljahr an eine umfassende Einführung in ein Gesundheitsprogramm anbieten, welches durch einen Spezialisten koordiniert wird.

Résumé Alors que du temps de Robert Koch, les maladies infectieuses étaient les principaux déterminants de la morbidité et de la mortalité, la mort et la souffrance sont aujourd'hui causées le plus souvent par des maladies non transmissibles. Ces dernières ont la caractéristique d'être la conséquence de notre propre style de vie, en particulier l'usage du tabac et les excès alimentaires. En étant attentifs à la nature, nous pouvons identifier les facteurs de risque des cancers, explorer leur mécanisme d'action, et mettre en place des stratégies préventives permettant leur réduction ou leur modification: en somme, on peut diminuer l'incidence des maladies et la mortalité. Un exemple du rôle de la surcharge métabolique dans la carcinogenèse est l'effet de la surconsommation de graisses alimentaires sur le développment et la progression du cancer du sein. La pathogenèse générale du cancer, les risques associés avec les surcharges métaboliques sont comparés aux conséquences d'une sous-consommation. Pour augmenter l'impact de la médecine préventive audelà de l'éducation alimentaire en Allemagne, nous recommandons que a) chaque faculté de médecine ait un départment de médecine préventive actif dans les domaines de l'épidémiologie et la promotion de la santé, b) tous les écoliers devraient avoir dès le début de leur scolarité une éducation sanitaire globale, dont l'enseignement serait coordonné par un spécialiste de l'éducation à la santé.
  相似文献   
96.
Isolated outer hair cells (OHCs) were partially sucked into especially designed cell capillaries allowing an experimental reconstitution of the cells' electroanatomy. The experimental approach separated the apical from the basolateral parts of the cells thus forming an artificial scala media and scala tympani. Resistance between both was 121 +/- 42 M omega. A sequence of negative and positive pressures was applied to the basal cell pole allowing "pulling" or "pushing" of the sensory cell investigated. The resulting length changes together with the known pressures allowed the estimation of an actual longitudinal compliance of 354 +/- 35 m/N. Following "pulling" OHCs tended to resume their initial shape after the force had ceased to be effective indicating elastic distortions. The calculated elasticity modulus of OHCs amounted to 6.1 +/- 3.4 kN/m2. From this data an actual longitudinal whole cell stiffness of OHCs of 3 x 10(-3) N/m was calculated. Ultrasound scanning of immobilized OHCs identified the cuticular plate (CP) and a central core between CP and basal cell pole as structures contributing to the cells' acoustic stiffness. Changes of the potential differences between the artificial scala media and scala tympani resulted in active length changes following the command voltage with a slope of delta 1/(1 x U) = 0.055 V-1. Assuming the validity of Hooke's law, the force generation associated with the active length changes can be calculated since the compliance is known.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
97.
A brief questionnaire (12 items) was developed to assess aspects of anger that could be expeditiously obtained during health screenings where medical students and residents can acquire valuable research and clinical experience simultaneously. Blood pressures were measured immediately upon sitting and after 3 minutes in 179 subjects who attended a health fair in Nashville. The questionnaire was administered after both blood pressure measurements were acquired. Scores on the measure of anger correlated significantly (P = .0009) with resting systolic blood pressure (SBP) in both blacks and whites while a measure of "John Henryism" showed no correlation with blood pressure in either group (P = .81). The findings are consistent with the literature in supporting a connection between anger and blood pressure but do not support the relationship between John Henryism and blood pressure.  相似文献   
98.
The DSM-IV Child Psychiatry Work Group surveyed 460 child psychiatrists about their use of DSM-III-R and their reactions to specific proposed nosological revisions for DSM-IV. This paper presents the responses of the sample as a whole and of respondent subgroups with different theoretical, practice, and training characteristics. The survey indicates that DSM-III and DSM-III-R are widely used and generally accepted by child psychiatrists. Ninety-eight percent of respondents believe a criterion-based diagnostic system is useful, and 65% consider DSM-III-R to be an improvement over DSM-III. Depending on the diagnosis 47% to 66% of the respondents reported that they generally assess all applicable criteria and 28% to 49% often refer to the manual before assigning a diagnosis. A majority of respondents supported proposals for several new diagnostic subtypes. Ninety-three percent of respondents indicated that "adequacy of family support" was very valuable for treatment planning or estimating prognosis. Fifty-five percent of respondents admitted to diagnosing adjustment disorders in order to avoid the stigma associated with other disorders. Child psychiatrists who are psychodynamically oriented or practicing in an office-based setting or out of training for more than 10 years tend to use the DSM-III-R less rigorously.  相似文献   
99.
Screening for complement deficiency in bacterial meningitis   总被引:1,自引:0,他引:1  
Seventy-seven children with bacterial meningitis were screened for complement deficiency. Both the classical and the alternate pathways were normal in 75 patients. Transiently reduced total haemolytic activity of the classical pathway was documented in a boy with meningococcal meningitis. Total haemolytic activity of both the classical and the alternate pathways were reduced in another patient with pneumococcal meningitis: individual complement components determination indicated predominant activation of the alternate pathway.  相似文献   
100.
Foix-Chavany-Marie syndrome (FCMS) is a distinct clinical picture of suprabulbar (pseudobulbar) palsy due to bilateral anterior opercular lesions. Symptoms include anarthria/severe dysarthria and loss of voluntary muscular functions of the face and tongue, and problems with mastication and swallowing with preservation of reflex and autonomic functions. FCMS may be congenital or acquired as well as persistent or intermittent. The aetiology is heterogeneous; vascular events in adulthood, nearly exclusively affecting adults who experience multiple subsequent strokes; CNS infections; bilateral dysgenesis of the perisylvian region; and epileptic disorders. Of the six cases reported here, three children had FCMS as the result of meningoencephalitis, two children had FCMS due to a congenital bilateral perisylvian syndrome, and one child had intermittent FCMS due to an atypical benign partial epilepsy with partial status epilepticus. The congenital dysgenetic type of FCMS and its functional epileptogenic variant share clinical and EEG features suggesting a common pathogenesis. Consequently, an increased vulnerability of the perisylvian region to adverse events in utero is discussed. In honour of Worster-Drought, who described the clinical entity in children 40 years ago, the term Worster-Drought syndrome is proposed for this unique disorder in children.  相似文献   
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