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41.
Lung cancer is the most prevalent malignancy in western countries and most of the patients present at advanced stages, but single splenic metastasis is exceptional instead. We report on a case of a seventy-three-year old male presenting with non-hemoptoic productive cough, constitutional syndrome and pain in the left lower quadrant. Physical examination and complementary radiological and hystologycal procedures revealed the presence of an adenocarcinoma of the left lung with probable splenic metastasis. The patient underwent splenectomy, which confirmed the diagnose of splenic metastasis of lung adenocarcinoma and, secondly, lung resection was performed. Topics about lung cancer metastasis are discussed.  相似文献   
42.
Summary The long-term efficacy of a new vasodilator, cadralazine (ISF 2469), and chlorthalidone have been compared in 20 hypertensive patients not adequately controlled by atenolol. After 4 weeks of treatment with atenolol 100 mg once daily, patients whose diastolic blood pressure was >95 mmHg were randomly divided into two groups to receive in addition to atenolol, either cadralazine 15 mg once daily or chlorthalidone 25 mg once daily. Both treatments were administered for 6 months. At the end of treatment with atenolol and after 3 and 6 months of combination therapy, blood pressure and heart rate were measured at rest and during bicycle exercise 24 h after the last dose. Compared to atenolol alone, both cadralazine and chlorthalidone caused a significant and similar reduction in resting blood pressure. Both groups showed an increase in diastolic blood pressure during exercise while receiving atenolol alone. The addition of chlorthalidone did not modify the pressor response to exercise, whereas patients taking cadralazine had a decrease in exercise diastolic blood pressure, which was fully evident after 6 months of therapy. The reduction in exercise diastolic blood pressure induced by cadralazine was proportional to the increase in exercise heart rate, suggesting a fall in peripheral vascular resistance. Chlorthalidone caused a significant increase in serum glucose and uric acid and a decrease in K+, whereas no change was observed during cadralazine It is concluded that cadralazine given once a day with atenolol has the same efficacy in controlling blood pressure at rest as the combination of atenolol and chlorthalidone, and in addition it improves the pressor response to dynamic exercise and does not cause unwanted metabolic effects.  相似文献   
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44.
A system to simultaneously measure the total deposition of four different sizes of monodisperse microspheres in normal and damaged lungs of rats was developed and tested. The system reproducibly measured the deposition of microspheres in control rats, and the procedure was shown to be sufficiently sensitive to measure ozone-induced changes in deposition rates. Rats exposed to 1.2 ppm ozone 6 h/d for 2 consecutive days showed greater deposition of the 1.09-micron-, 2.02-micron-, and 2.99-micron- but not of the 0.48-micron-diameter microspheres when compared to controls. After 8 consecutive days of exposure to the same concentration of ozone, there were no differences in deposition rates between control and ozone-exposed rats. Respiratory physiology and lung histopathology data provided evidence that subtle changes in the airway architecture and/or aerodynamics were likely to be responsible for the differential deposition rates as a function of the duration of ozone exposure.  相似文献   
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46.
Recent longitudinal studies using personality questionnaires and ratings have shown remarkable stability across the adult years. In an investigation of age changes and differences in personality as measured by the Holtzman Inkblot Technique (HIT), ninety-three men and women aged twenty-five to ninety were administered Form A of the HIT; forty-four of these were retested one to three years later. Stability coefficients ranged from .07 for Form Appropriateness to .73 for Form Definiteness, with most variables showing significant but moderate stability. Repeated measures analyses of variance showed increases in six variables and decreases in two others, but only one of these changes was paralleled by cross-sectional age differences. Correlations with self-report measures of the broad personality domains of neuroticism, extraversion, and openness to experience failed to show hypothesized relations, and the associations seen were attributable to chance. It was concluded that the HIT measures perceptual-cognitive variables that are moderately stable in adulthood.  相似文献   
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48.
Muscarinic receptor-stimulated phosphoinositide metabolism has been recently suggested as a possible target for the neurotoxic effects of ethanol during brain development. Since two other alcohols, tertiary butanol and n-propanol, have been shown to cause microencephaly in the rat when administered during the brain growth spurt, in the present study we investigated the in vitro effects of five short chain aliphatic alcohols on muscarinic receptor-stimulated phosphoinositide metabolism in cerebral cortical slices from 7 day-old rats. In neonatal animals all alcohols tested inhibited carbachol (1 mM)-stimulated [3H]inositol phosphates accumulation in a dose- and time-dependent manner. The order of potency was t-butanol greater than n-propanol greater than or equal to iso-propanol greater than ethanol greater than methanol. After 90 min of incubation, ethanol, n-propanol and t-butanol caused a significant inhibition of muscarinic receptor-stimulated inositol metabolism at doses as low as 15 - 50 mM, comparable to the blood concentrations reached after in vivo administration of doses able to induce developmental neurotoxicity. The inhibitory effect of ethanol was additive to that of iso-propanol or t-butanol. Differently from these effects in 7 day-old rats, in cortical slices from adult animals methanol and ethanol had no effect on carbachol-stimulated phosphoinositide metabolism, while the two propanol isomers and t-butanol were less effective than in neonatal animals. These results suggest that muscarinic receptor-coupled phosphoinositide metabolism might be a common neurochemical target for the developmental neurotoxicity of short chain aliphatic alcohols.  相似文献   
49.
The mechanism of delayed neurotoxicity, triggered by glutamate, was studied in 7-8-day-old primary cultures of rat cerebellar granule cells. Treatment of cultures for 15 min with 50 microM glutamate in Mg2+ -free medium, followed by removal of the excitoxin, resulted in neuronal death, which started to appear 2-3 hr after the termination of glutamate treatment. The number of dead neurons increased gradually in the next few hours and 80-85% of neurons were found dead 24 hr later. Antagonists of N-methyl-D-aspartate-sensitive glutamate receptors (phencyclidine) or 1.2 mM MgCl2, but not the antagonist of N-methyl-D-asparatate-insensitive glutamate receptors (6-cyano-7-nitroquinoxaline-2,3-dione), abolished the neurotoxic effect of kainate. Development of glutamate-induced neuronal death depends strongly on Ca2+. Removal of extracellular Ca2+ (with 1mM ethyleneglycol-bis-(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid) immediately after the termination of glutamate exposure and before the appearance of the early signs of neuronal death (post-glutamate period) dramatically reduced neuronal degeneration. Neurotoxic concentrations of glutamate induced sustained increase of 45Ca2+ uptake in the post-glutamate period. The delayed increase of 45Ca2+ uptake, as well as the delayed neurotoxicity, were not affected by post-glutamate treatment with phencyclidine, dibenzocyclohepteneimine; DL-2-amino-5-phosphonovalerate, or MgCl2 or with voltage-dependent Ca2+ channel blockers (nitrendipine, verapamil, diltiazem). Neurotoxic concentrations of glutamate also induced a delayed sustained increase of [3H]phorbol-12,13-dibutyrate binding, reflecting an increased translocation of protein kinase C (PKC) from cytosol to the cell membrane during the post-glutamate period. Pretreatment of neurons with the ganglioside GT1b (trisialosylgangliotetraglycosylceramide), followed by removal of free GT1b from the incubation medium, prevented PKC translocation, the sustained increase of 45Ca2+ uptake in the post-glutamate period, and the delayed neuronal death. We suggest that the sustained activation and translocation of PKC primed by glutamate receptor stimulation may be the triggering event causing the protracted increase of neuronal Ca2+ influx. This influx is insensitive to voltage-dependent Ca2+ channel blockers and glutamate receptor antagonists. It appears that this delayed increase of Ca2+ influx may be important in causing neuronal death.  相似文献   
50.
Six treatment-resistant schizophrenic patients were given a ten-week single-blind trial of carbamazepine. Treatment resistance was determined on the basis of documented failure to respond to treatment with at least three neuroleptic drugs from two different chemical classes. The adjunctive use of carbamazepine resulted in a significant improvement of the negative symptoms of schizophrenia. These symptoms are often poorly responsive to conventional antipsychotic drugs. Therefore, controlled studies should be performed to further assess the possible efficacy of carbamazepine in schizophrenia.  相似文献   
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