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81.
82.
An unusual association with Raynaud's phenomenon   总被引:1,自引:1,他引:0  
A 36-yr-old lady with a year of typical Raynaud's and polyarthralgiahad a normal examination other than cold peripheries and bloodpressure of  相似文献   
83.
The steady-state density and the turnover rates of D1-dopamine receptors were investigated in the striatum, nucleus accumbens, substantia nigra, and retina of adult (3-month-old) and aged (23-month-old) rats. The turnover rates were measured by monitoring the repopulation kinetics of D1-dopamine receptors labeled with [3H]-SCH 23390 after the irreversible inactivation induced by a single dose of N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ, 10 mg/kg, s.c.). In all the neural tissues examined, the repopulation of D1 dopamine receptors could be adequately described by a theoretical model that assumes a constant rate of receptor production (i.e. zero order) and a rate of degradation that is dependent on the receptor density at any time (i.e. first order). The results obtained indicate that the reduction in the density of D1-dopamine receptors in the striatum, nucleus accumbens and substantia nigra of aged rats is the result of a larger decrease in the receptor production rate (−44 to −60%) than in the receptor degradation rate (−21 to −46%). By contrast, the production rate of D1-dopamine receptors in the retina of aged rats remains unchanged, whilst the degradation rate is reduced by 25%. This results in an age-related increase in the density of D1-dopamine receptors in the rat retina.  相似文献   
84.
The synthesis of some N,N-disubstituted 4-amino-5,6-dihydro-3-phenyl-2H-[1]benzothiepino [5,4-b]pyran-2-ones by reaction of phenylchloroketene with a series of N,N-disubstituted (E)-4-aminomethylene-3,4-dihydro-1-benzothiepin-5(2H)-ones, followed by dehydrochlorination of the primary adducts with DBN, is described. The 4-methylphenylamino derivative showed a local anesthetic activity in mice superior to that of lidocaine and the 4-morpholino derivative showed an antiarrhythmic activity in rats comparable to that of quinidine.  相似文献   
85.
BACKGROUND: The use of immunosuppressive medication is a dominant risk factor for infection in patients with rheumatoid arthritis (RA). Methotrexate (MTX) is one of the traditional disease-modifying antirheumatic drugs. Adalimumab [a human anti-tumor necrosis factor-alpha (anti-TNF-alpha) monoclonal antibody] represent an important advance in the treatment of RA and has been recently come in use. TNF-alpha plays a role in the host defense against Mycobacterium tuberculosis and notably in granuloma formation. Infections occur at a high rate among those who use one or the combination of the two medications. METHOD: We examined a female patient that was referred to our department for evaluation and treatment of a granular lesion on the soft palate and uvula, complaining of mild dysphagia. The patient was treated for 4 months with MTX and adalimumab for RA before the oral lesion appeared. RESULTS: The histopathological examination of a specimen of the oral lesion, taken by biopsy, showed a chronic inflammation characterized by tuberculous granulomas. Polymerase chain reaction test and culture of a new specimen was positive for M. tuberculosis. CONCLUSIONS: The therapeutic use of MTX or/and adalimumab for the treatment of RA or few others diseases, can cause oral tuberculosis.  相似文献   
86.
Summary This paper focuses on improving the accuracy of sample size calculations for cohort studies by careful calculation of the expected number of deaths in the population, taking into account either prior information or realistic assumptions about variables which may affect the mortality or incidence. Sometimes small changes in the assumptions can dramatically alter the expected numbers and may necessitate modifications in the design of the study. Possible modification include extension of the follow-up time, and recognition that the real strength of the study may lie in the potential for pooling several similar studies. The problem will be discussed with reference to two examples of occupational cohort studies where differing prior information was available.
Zusammenfassung Diese Arbeit beschäftigt sich mit der Genauigkeit der Berechnung des Stichprobenumfangs in Kohortenstudien, wenn detaillierte Berechnungen für die erwartete Zahl der Verstorbenen berücksichtigt werden. Dies kann entweder durch die Ausnutzung vorhandener Informationen oder durch realistische Annahmen über die Faktoren, die Mortalität oder Inzidenz beeinflussen, geschehen. Schon kleine Unterschiede in diesen Annahmen kann die erwartete Zahl der Verstorbenen erheblich verändern und es notwendig machen, das Design einer Studie zu verändern. Solche Modifikationen bestehen z.B. in der Verlängerung der Follow-up Zeit der Studie oder in der Einsicht, dass es nötig ist, Daten aus mehreren Studien zusammenzufassen. Die Probleme werden anhand von zwei Beispielen aus dem Bereich der Berufsepidemiologie diskutiert.

Résumé Cet article concerne la précision des estimations de taille d'échantillons pour les études de cohortes. Le calcul précis du nombre de décès attendus dans la population prend en compte les variables susceptibles d'affecter la mortalité ou l'incidence, provenant soit d'une connaissance préalable, soit d'hypothèses réalistes. De modestes changements d'hypothèses peuvent parfois altérer de façon substantielle les nombres attendus et nécessiter des modifications dans le protocole de l'étude. Parmi les modifications possibles, il faut citer la prolongation du temps de suivi de l'étude ainsi que le constat que la valeur réelle de l'étude pourrait reposer sur la possibilité de mise en commun de plusieurs études similaires. Le problème est discuté à l'aide de deux exemples d'études de cohortes professionnelles pour lesquelles différentes informations préalables sont disponibles.
  相似文献   
87.
88.
1. Airways derived from different levels of the lung exhibit a difference in the reactivity and sensitivity to agonists. We have evaluated the effect of acetylcholine and cholinergic selective (pirenzepine, gallamine and 4-dipherylacetoxymethyl piperidine [4-DAMP]) and non-selective (atropine) antagonists on bovine proximal and distal smooth muscle preparations. 2. The distal preparations are more sensitive to acetylcholine than proximal bronchi. The relaxant effect of three selective antagonists on the distal and proximal tissues was the same when the results for each drug were compared. 3. Atropine and 4-DAMP were more potent than pirenzepine and gallamine in relaxing both proximal and distal bovine smooth muscle preparations. 4. These data suggest that the muscarinic sites on the smooth muscle of bovine airways are of the M3 subtype.  相似文献   
89.
Cultures ofTrypanosoma (Megatrypanum) freitasi with L929 mouse fibroblasts at 27.5°C were examined by scanning and transmission electron microscopy in an attempt to clarify the processes of colony formation by the epimastigotes and of their attachment to substrata. It was seen that the flagellates occupy intercellular spaces and do not associate with intact fibroblasts. As the trypanosome population increases, ever larger portions of the substratum are cleared of fibroblasts and occupied by conglomerates of epimastigote colonies consisting of about a dozen organisms that attach to the substratum by their anterior extremities and form pyramidal clusters. Attachment of the epimastigotes involves the flagellar membrane, which becomes extraordinarily enlarged and assumes various aspects of broad sheets, filaments and loops over the substratum or along the flagellum, which exhibits a shortened axoneme. Desmosome or hemidesmosome plaques are present when the attachment takes place between membranes or between the membrane and the substratum.Supported by grants from CNPq and FINEP  相似文献   
90.
Studies have shown that students and the general population have little knowledge about nursing schools and the nursing profession. This study investigates the extent to which a sample of the population of Brazil is aware of the existence of nursing schools, and how they have obtained this information. Data were collected by telephone interviews. The sample consisted of 326 subjects whose telephone numbers were taken from the telephone book. Analysis showed that 73% of the subjects were aware of the existence of two nursing schools in the city; however, 65.03% did not know the names of these schools. Direct communication with friends and family, as well as indirect communication by television and advertising, were the sources of information mentioned by those questioned.  相似文献   
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