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71.
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BACKGROUND: Tuberculin reactivity varies on the basis of the PPD lot and the population studied. AIMS: To compare tuberculin reactivity in the elderly following successive applications of PPD from 2 different lots. POPULATION: Elderly nursing-home residents, from the province of Guadalajara, Spain. METHODS: The elderly were randomly selected and administered with a first Mantoux intradermoreaction of 2 UT of PPD-RT23 or 2 UT of PPD-CT68. The study was performed in a scaled basis, eliminating the reactors (transversal induration > or = 5 mm at 72 h). The non reactors were restudied with a second and third test in alternative arms at a 7-day interval with the same lot and initial dosis of PPD. At one year the scaled study was repeated with 2 UT of PPD-CT68. RESULTS: Eight hundred and thirty elderly persons (79 +/- 9 years) were studied, with 410 receiving PPD-RT23 and 420 receiving PPD-CT68. No differences were observed in the percentage of initial reactors (31% vs 29%; p = 0.26) or in the booster reactors (23% vs 20%; p = 0.16). The PPD-RT23 was found to trigger more intensive reactions than the PPD-CT68 leading to a greater frequency of indurations > 14 mm. After one year, the percentage of stable reactions was similar in both groups (50.5% vs 49.5%; NS). CONCLUSIONS: 1) In elderly nursing-home residents 2 UT of PPD-RT23 and 2 UT of PPD-CT68 showed similar results in regard to the number of reactors and the frequency of booster reactions. 2) The proportion of intense reactions was greater with 2 UT of PPD-RT23 than with 2 UT of PPD-CT68. 3) The stability of the reactions at one year was independent of the lot used in the first phase.  相似文献   
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The analysis of 49 fatal cases of venous thromboembolism--VTE (15% of total ambulatory patients number during long observation was performed. The advanced age of patients, multiple risk factors, underlying circulatory and respiratory tract diseases, malignancies, previous episodes of VTE especially with secondary pulmonary hypertension were the most important factors determining fatal prognoses in those patients.  相似文献   
75.
Pharmacological effects of acute treatment with venlafaxine (VEN), a clinically active antidepressant [a noradrenaline (NA) and 5-hydroxytryptamine (5-HT) reuptake inhibitor without any affinity for neurotransmitter receptors] were studied in mice and rats. VEN inhibited the reserpine- or apomorphine-induced hypothermia and enhanced the L-5-HTP-induced head twitches in mice. It reduced the immobility time in Porsolt's test in mice and rats, but either did not change the locomotor activity (mice) or decreased it (rats). VEN reduced the locomotor hyperactivity induced by amphetamine (AMP), apomorphine (APO) and quinpirole (QUI), as well as the APO-induced stereotypy; the stereotypy induced by AMP in rats was prolonged. VEN neither changed the clonidine-induced aggressiveness in mice nor the behavioral syndrome induced by oxotremorine in rats. The obtained results indicate that VEN, given acutely, shows a pharmacological profile similar to that of tricyclic NA and 5-HT reuptake inhibitors. In contrast to the antidepressants mentioned above, VEN does not exhibit an alpha 1-adrenolytic or a cholinolytic activity (in vivo tests).  相似文献   
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We have identified mutations in Raf-1 that increase binding to Ras. The mutations were identified making use of three mutant forms of Ras that have reduced Raf-1 binding (Winkler, D. G., Johnson, J. C., Cooper, J. A., and Vojtek, A. B. (1997) J. Biol. Chem. 272, 24402-24409). One mutation in Raf-1, N64L, suppresses the Ras mutant R41Q but not other Ras mutants, suggesting that this mutation structurally complements the Ras R41Q mutation. Missense substitutions of residues 143 and 144 in the Raf-1 cysteine-rich domain were isolated multiple times. These Raf-1 mutants, R143Q, R143W, and K144E, were general suppressors of three different Ras mutants and had increased interaction with non-mutant Ras. Each was slightly activated relative to wild-type Raf-1 in a transformation assay. In addition, two mutants, R143W and K144E, were active when tested for induction of germinal vesicle breakdown in Xenopus oocytes. Interestingly, all three cysteine-rich domain mutations reduced the ability of the Raf-1 N-terminal regulatory region to inhibit Xenopus oocyte germinal vesicle breakdown induced by the C-terminal catalytic region of Raf-1. We propose that a direct or indirect regulatory interaction between the N- and C-terminal regions of Raf-1 is reduced by the R143W, R143Q, and K144E mutations, thereby increasing access to the Ras-binding regions of Raf-1 and increasing Raf-1 activity.  相似文献   
78.
The study of the morphology of eggs, larvae, pupae and adults of Aedes excrucians from Germany, Italy and France has led the authors to rise again the binomen Aedes surcoufi (Theobald, 1912) to particularize the european populations. At the same time, the characteristics of the different species of the Aedes excrucians complex are discussed.  相似文献   
79.
In sheep and calf ventricular bundles, increasing the internal calcium by increasing the frequency of voltage-clamping to plateau range potentials increased the time-independent outward current. This effect was more marked with higher [Ca]o, and was reduced if the Ca current blockers Verapamil or D 600 were used. 2. If the internal Ca was increased by the addition of cyanide and reduction of external sodium the outward current was also increased. The frequency-dependent increase in outward current also occurred in this Na-poor (12 mM) solution. 3. Tension measurement on the ventricular bundles showed that a Na-free solution with cyanide did not cause a contracture. On changing from Tyrode to a Na-free solution containing cyanide, and on changing back to Tyrode there was a potentiation of the twitch. 4. In Na-poor solution with cyanide, although no contracture was found, ECa was less positive, suggesting that under these circumstances Ca accumulates at the inner side of the membrane, but not around the myofibrils. 5. The prolongation of the action potential in Cl-free solution is frequency-dependent. A greater prolongation is seen at lower frequencies suggesting that Cl current is relatively more important for repolarization at lower frequencies of stimulation. 6. It is suggested that calcium at the inner side of the membrane sets the level of the background outward current. A feed-back mechanism on this basis is proposed for the control of the action potential duration. Various factors that could influence this basic mechanism are discussed.  相似文献   
80.
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