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991.
Nine years after the beginning of the epidemic of freebase (crack) cocaine abuse in the Bahamas, this historical study was done to characterize the natural course of the epidemic and to estimate the effectiveness of control measures. The authors' data include the incidence of new cases at the only psychiatric hospital in the Bahamas and at the primary community psychiatric clinic in the nation. The Bahamian response included 1) demand reduction, 2) supply reduction, and 3) reduction of money laundering. The annual number of new cases of crack abuse presenting for treatment declined from 1987 to mid-1991 in both facilities, but in 1992 it began rising again in the inpatient setting only. The changes in recent years have been accompanied by an increase in violent crimes against persons, especially robberies. (American Journal on Addictions 1994; 3:14–24)  相似文献   
992.
Dipyridamole thallium scanning (DTS) is an imaging technique with good sensitivity for coronary artery disease (CAD). The purpose of this study was to compare the haemodynamic courses and the correlation between pulmonary capillary wedge pressure (PCWP) and central venous pressure (CVP) in patients with normal DTS (Group 1: n = 12) with those whose scans demonstrated CAD (Group2: n = 11). Haemodynamic profiles were obtained prior to anaesthesia and at several times during surgery. The haemodynamic courses in both groups were similar with significant decreases in cardiac index, stroke index, and left ventricular stroke work index during aortic cross-clamping compared with values prior to anaesthesia. There were no significant changes in PCWP and CVP throughout the study. The correlations between PCWP and CVP were significant in both groups as were the correlations between the changes in PCWP and the changes in CVP observed at the time of cross-clamping. These correlations all had large standard errors of the estimate, however, making it impossible to predict the PCWP from the CVP with precision. It is concluded that, in a limited study population, an abnormal DTS did not identify patients in whom the PCWP and CVP correlated poorly during abdominal aortic aneurysmectomy.  相似文献   
993.
994.
Bilateral six-hydroxydopamine (6-OHDA) lesions were placed in the amygdala of rats self-administering cocaine (1.5 mg/kg per injection i.v.) under a progressive ratio schedule of reinforcement. Post-lesion access to three doses of cocaine (1.5, 0.75 and 0.37 mg/kg per injection i.v.) revealed a lesion effect only at the highest dose. At this dose, the lesion caused a significant increase in breaking point. No change in the breaking point was produced at the lower two doses. The biochemical results show a significant reduction in dopamine and DOPAC levels within the amygdala and an increase in dopamine within the NACC. In contrast, noradrenaline and serotonin (5-HT) levels were unaffected by the lesion in any of the dissected areas. These results demonstrate that no specific effect on cocaine reinforcement was produced by 6-OHDA lesions of the amygdala. The possibility that the lesion may have attenuated the anxiogenic qualities of the high dose of cocaine is discussed.  相似文献   
995.
Noninvasive diagnosis of cavernous hemangioma of the liver is an important step in the investigation of patients with focal hepatic lesions since biopsy may result in life-threatening hemorrhage. To determine the diagnostic accuracy of 99m-technetium red blood cell (99mTc-RBC) imaging with tomography, 50 patients with various types of focal liver lesions were studied. Thirty-two patients had 45 hemangiomas and 7 other benign lesions while 18 patients had either primary (n=8) or secondary (n=10) hepatic malignancies. Tomographic imaging identified 12 more hemangiomas than planar imaging, improving sensitivity from 53% to 80%, and was found most useful for detection of smaller lesions (mean size, 2.1 cm). Specificity for hemangiomas was 100% with all lesions greater than 1.9 cm showing the characteristic scintigraphic pattern of blood-pooling on delayed images. There was excellent agreement between 2 independent observers concerning interpretation of tomographic images (89% for the hemangioma group and 100% for other patients). Therefore99mTc-RBC scintigraphy with tomography is an accurate diagnostic technique in the investigation of cavernous hemangiomas. Its major value resides in its ability to distinguish hemangiomas from other types of hepatic pathology.
Resumen El diagnóstico no invasivo del hemangioma cavernoso del hígado es un paso de importancia en el proceso de investigación de pacientes con lesiones hepáticas focales, puesto que la biopsia puede resultar en hemorragia de consecuencias potencialmente fatales. Con el objeto de determinar la certeza diagnóstica de la tomografía con glóbulos rojos marcados con tecnecio 99m, se estudiaron 50 pacientes con varios tipos de lesiones hepáticas focales. Treinta y dos pacientes presentaron 45 hemangiomas y 7 lesiones benignas, en tanto que 18 pacientes presentaron neoplasias malignas primarias (n=8) o secundarias (n=10). Las imágenes tomográficas obtenidas por este método lograron identificar 12 hemangiomas más, en comparación con imágenes convencionales, aumentando la sensibilidad de 53% a 80%, y demostró ser de máxima utilidad para la detección de las lesiones más peque¯nas (tamaño promedio, 2.1 cm). La especificidad para los hemangiomas fue 100%, con todas las lesiones mayores de 1.9 cm exhibiendo el patrón centelleográfico característico de estancamiento sanguíneo en las imágenes tardías. Se encontró excelente correlación entre 2 observadores independientes en la interpretación de las imágenes tomográficas (89% para el grupo de pacientes con hemangiomas y 100% para el resto de los pacientes). En consecuencia, la escintigrafía con glóbulos rojos marcados con99mTc aparece como una técnica certera en el diagnóstico de los hemangiomas cavernosos. Su mayor valor reside en su habilidad para diferenciar los hemangiomas de otra clase de patología.

Résumé Le diagnostic non invasif d'hémangiome caverneux du foie est une étape importante dans l'investigation des patients ayant des lésions hépatiques focales, puisque la biopsie risque de se résoudre par une hémorrhagie menaçant le pronostic vital. Pour définir la précision diagnostique de la tomoscintigraphie après marquage des hématies au technetium 99m (99mTc), on a étudié 50 patients ayant des types différents de lésions focales du foie. Trente-deux patients avaient 45 hémangiomes et 7 lésions bénignes tandis que 18 patients avaient des tumeurs hépatiques malignes soit primaires (n=8) soit secondaires (n=10). L'imagerie tomographique a identifié 12 hémangiomes de plus que l'imagerie planaire, améliorant la sensibilité de 53% à 80% et s'est avérée très utile pour détecter les lésions plus petites (taille moyenne, 2.1 cm). La spécificité pour les hémangiomes était de 100% pour toutes les lésions dépassant 1.9 cm montrant les caractères scintigraphiques typiques d'accumulation de sang sur les images retardées. Il y a eu concordance totale entre 2 observateurs indépendents sur l'interprétation des images tomographiques (89% pour le groupe des hémangiomes et 100% pour les autres patients). Voilà pourquoi la scintigraphie99mTc avec tomographie est une technique de diagnostic précis dans l'investigation des hémangiomes caverneux. Sa valeur essentielle est sa capacité de distinguer les hémangiomes des autres types de pathologie hépatique.
  相似文献   
996.
997.
The level of psychiatric morbidity and perceived sources of stress among police officers were investigated using the General Health Questionnaire (GHQ) and a stress situation questionnaire, which were sent to 171 officers. Half of the responders were invited to attend group counselling sessions weekly for 12 weeks. Outcome measures studied were a second GHQ completed at the end of the treatment period and the amounts of sick leave taken in the 12-week period before, during and after the treatment period. The results were that 61 people returned the first GHQ of whom 59 were male and of whom 14 were classed as ‘cases’. Of the 31 assigned to the treatment group, 22 attended at least one session. Responses to the stress situation questionnaire and the content of counselling sessions tended to confirm the impression that internal aspects of the organization were viewed as prime sources of stress and dissatisfaction. There were no significant changes in GHQ score within or between groups, nor were there significant differences in the amount of sick leave taken. Nevertheless the sessions appeared to be valued and we conclude that this sort of intervention is at least feasible. We recommend that similar studies measure psychiatric morbidity during treatment and at follow-up, rather than immediately after finishing, when reactions to this termination are prominent.  相似文献   
998.
The effect of the novel 1,4-dihydronaphthyridine Ca2+ channel inhibitor Goe 5438 (CI-951) on voluntary ethanol consumption was examined in selectively bred alcohol-preferring (P) rats in a free choice two bottle preference test versus water. Intraperitoneally injected Goe 5438 dose-dependently (5, 10 or 20 µmol/kg, twice daily) inhibited ethanol and increased water intake over the 24 h period (injection day). The drug decreased ethanol preference, originally above 90%, by 6%, 19% and 45% at respective doses, on the injection day. That inhibitory effect of the highest dose of Goe 5438 on ethanol preference remained significant also on days 2 and 3 after injections (–51% and –18%, respectively). Goe 5438, in the highest dose, also tended to decrease granulated chow consumption during the injection day only. To further test whether the inhibition of ethanol preference is secondary to decrease in reinforcing properties of ethanol and not due to interference with satiety mechanisms, we compared the effect of two higher doses (10 and 20 µmol/kg, intraperitoneally, twice daily) of Goe 5438 on spontaneous preference for a non-caloric 0.04% saccharin solution in Sprague-Dawley rats. We observed a dose-dependent suppression of preference (by 44% and 58%, respectively) during the injection day, but not the subsequent 24 h period. However, Goe 5438 also significantly alleviated food pellet intake on the injection day. In conclusion, Goe 5438 produces potent and long-lasting inhibition of voluntary ethanol consumption, which may be secondary to attenuation of reinforcing properties of ethanol. Additionally, this particular Ca2+ channel inhibitor appears to have mild anorectic properties which may be conducive to acute suppression of alcohol intake.  相似文献   
999.
1000.
Using the rapid-response thermistor pulmonary artery catheter and transoesophageal echocardiography, this study examined the effects of 100 per cent oxygen, 70 per cent nitrous oxide/30 per cent oxygen, and 70 per cent nitrogen/30 per cent oxygen on the pulmonary circulation and ventricular function in ten patients with pulmonary hypertension. In comparison with baseline measurements, nitrous oxide administration resulted in small but statistically significant (P less than 0.05) changes in mean arterial pressure (76 +/- 14 to 67 +/- 12), mean pulmonary arterial pressure (37 +/- 14 to 33 +/- 13 mmHg), and cardiac output (3.7 +/- 1.4 to 3.2 +/- 1.1 L.min-1). Seventy per cent nitrogen resulted in no significant changes from baseline. The repeat 100 per cent oxygen measurements were nearly identical to the nitrous oxide measurements. It is concluded that nitrous oxide does not exacerbate pulmonary hypertension or ventricular dysfunction during high-dose fentanyl anaesthesia in patients with mitral valvular disease.  相似文献   
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