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51.
52.
The concentration of alpha-tocopherol was measured in liver biopsy specimens obtained from 83 patients with alcoholic and non-alcoholic liver diseases. The mean hepatic vitamin E content (as alpha-tocopherol) was significantly lower in 23 patients with alcoholic cirrhosis (17.6 +/- 12.1 nmol/mg wet weight liver), compared with 12 patients with normal liver histology (39.2 +/- 29.7 nmol/mg, P less than 0.01). The mean serum concentration of alpha-tocopherol was lower in patients with alcoholic cirrhosis (13.9 +/- 7.0 mumol/l) than in individuals with alcoholic fatty liver (21.3 +/- 9.3 mumol/l, P less than 0.01) and patients with normal liver histology (23.4 +/- 11.6 mumol/l, P less than 0.01). A decreased ratio of serum alpha-tocopherol/total serum lipids was also observed in patients with alcoholic cirrhosis, compared with patients with normal liver histology (P less than 0.05). There was a significant correlation between concentrations of alpha-tocopherol in liver and serum (r = 0.43, P less than 0.001). Furthermore, serum alpha-tocopherol correlated with retinol (r = 0.53, P less than 0.001), selenium (r = 0.45, P less than 0.001), and albumin (r = 0.37, P less than 0.001) in serum. We suggest that the reduced content of hepatic alpha-tocopherol observed in some patients may play a role in ethanol-induced lipid peroxidation.  相似文献   
53.
Three patients,with known brain injury and neuropsychological impairments, are followed through an individualized cognitive rehabilitation programme and post discharge from the treatment programme. Single Photon Emission Computed Tomography (SPECT) of the brain was employed to evaluate resting relative cerebral blood flow (rCBF) during the process of recovery from brain injury. All patients experienced significant improvements on measures of neuropsychological functioning and improvements in rCBF during this longitudinal study. The specific changes in rCBF appear to be related to the location of the patient s brain injury and strategies particular to cognitive rehabilitation therapy. Continued improvements in rCBF, functional abilities, and cognitive skills were documented in these three cases up to 45 months post brain injury.  相似文献   
54.
Background: Many studies have addressed the effect of the timing of surgery for breast cancer relative to menstrual cycle phase, with conflicting results. Explanations for the possibility that survival could be altered by the appropriate timing of breast cancer surgery in humans remain speculative. Methods: We examined the expression of three estrogen related proteins (c-erbB-2, cathepsin D, pS2) in the breast tumors from 69 premenopausal women sampled in different phases of the menstrual cycle. Data on S-phase fraction and hormone receptor expression were also analyzed. Immunohistochemical assays were used to measure the proteins of interest. S-phase fraction was determined by flow cytometry. Analyses were performed based on fraction of cells staining positive for the protein, density of stain, and a histoscore that combined both fraction of positive cells and density. Results: We found no differences in c-erbB-2, cathepsin D, hormone receptor, or S-phase levels in tumors sampled in the follicular versus luteal phase, or perimenstrual versus periovulatory phase. The exception was pS2, which was expressed at greater levels during the luteal than during the follicular phase of the cycle (p<0.01); but there was no difference in pS2 expression when the patients were classified as periovulatory versus perimenstrual. Conclusions: Our findings do not support a variation in c-erbB-2, cathepsin D, S-phase fraction, or receptor expression as an explanation for the differences in breast cancer prognosis when surgery is timed by menstrual cycle phase. The finding that pS2 (an indicator of hormone sensitivity, and possibly better prognosis) is expressed at higher levels in tumor samples during the luteal phase suggests that the biologic profile of breast tumors may vary with the menstrual cycle and that these variations deserve further study.  相似文献   
55.
The effects of the enantiomers of 5-fluoro-8-hydroxy-2-(dipropylamino)tetralin, UH-301 and the potent 5-HT1A-receptor agonist (R)-8-hydroxy-2-(dipropylamino)tetralin, (R)-8-OH-DPAT, on locomotion, rearing and total activity were studied in rats. The experiments were performed as tests either of exploratory activity in non-habituated rats or of motor activity of rats habituated to the environment for 2 h before drug injection. (R)-8-OH-DPAT increased locomotion and total activity and decreased rearing in both conditions. (R)-UH-301 increased locomotion and slightly also total activity in habituated rats and decreased rearing in both conditions. (S)-UH-301 decreased locomotion and rearing in both conditions but only in doses of 10 mumol/kg and above. Lower doses of (S)-UH-301 (10 mumol/kg) antagonized (R)-8-OH-DPAT-induced increases of locomotion and total activity. As (S)-UH-301 decreased rearing, per se, it was not able to antagonize the (R)-8-OH-DPAT induced decrease. These results further support previous data that (S)-UH-301 is a 5-HT1A antagonist while (R)-UH-301 is a 5-HT1A agonist.  相似文献   
56.
ABSTRACT: Programs for preventing violence among youth should be evaluated to determine if they are effective. Nurses' logs appear to be a useful tool for evaluating school-based violence prevention programs. The logs provide a record of students' visits to the school nurse that can be used to determine if a violence prevention program is associated with a reduction in fighting—and other injury-related nurse visits. This method has many strengths: it is simple and inexpensive, it does not interrupt the school routine, it permits school-level rather than student-level data collection, it provides a ready "baseline," and it allows continuous data collection. However, potential limitations do exist. For example, the method may provide insufficient information and may be affected by factors unrelated to the intervention. School officials can increase the usefulness of the logs by encouraging standardization and providing training in their use.  相似文献   
57.
Neonatal rat motoneurones are electrically coupled via gap junctions and the incidence of this coupling declines during postnatal development. The mechanisms involved in this developmental regulation of gap junctional communication are largely unknown. Here we have studied the role of NMDA receptor-mediated glutamatergic synaptic activity in the regulation of motoneurone coupling. Gap junctional coupling was demonstrated by the presence of graded, short latency depolarising potentials following ventral root stimulation, and by the transfer of the low molecular weight tracer Neurobiotin to neighbouring motoneurones. Sites of close apposition between the somata and/or dendrites of the dye-coupled motoneurones were identified as potential sites of gap junctional coupling. Early postnatal blockade of the NMDA subtype of glutamate receptors using the non-competitive antagonist dizocilpine maleate (MK801) arrested the developmental decrease in electrotonic and dye coupling during the first postnatal week. These results suggest that the postnatal increase in glutamatergic synaptic activity associated with the onset of locomotion promote the loss of gap junctional connections between developing motoneurones.  相似文献   
58.
59.
Cardiac output was determined with an indicator dilution technique during digital venous angiography of the left ventricle in 11 patients. The contrast medium injected into the right atrium was used as indicator. During and after the injection of contrast medium one blood sample per second was obtained through a catheter placed in the descending aorta. The samples were analyzed for iodine content with x-ray fluorescence analysis and cardiac output determined ad modum Stewart-Hamilton. Thermodilution was used as a reference method. The results indicate that the indicator dilution method with the use of contrast medium might be used for calibration of videodensitometric methods for blood flow measurements.  相似文献   
60.
The clinical and economic effects of each of 3 alternatives—no prophylaxis, general prophylaxis, and selective treatment—have been assessed in conjunction with 3 types of surgery—general surgery, the subset surgery for cholelithiasis, and elective hip surgery. The costs of thromboembolic and hemorrhagic complications have been calculated from the figures for 28 patients hospitalized at the Department of Surgery, Malmö General Hospital, Malmö, Sweden. The anticipated number of thromboembolic complications—and thus even the number of fatal pulmonary embolisms—can be minimized in all 3 types of surgery by means of general prophylaxis. General prophylaxis with low-dose heparin is, however, accompanied by the greatest incidence of hemorrhagic complications. Health care costs are minimized with general prophylaxis in elective hip and general surgery, while no prophylaxis is the best alternative in surgery for cholelithiasis. From the patient's point of view, general prophylaxis minimizes the duration of thromboembolic disease in general surgery as well as in elective hip surgery. In surgery for cholelithiasis, however, no differences in health loss for the individual are shown between the 2 main alternatives, no prophylaxis and general prophylaxis. Selective treatment means treatment after diagnosis of thrombosis with some screening method. The alternative selective treatment was the least satisfactory of those 3 studied.
Resumen Los efectos clínicos y económicos de cada una de 3 alternatives en la profilaxis tromboembólica (no profilaxis, profilaxis general con heparina de baja dosis, y tratamiento selectivo) fueron valorados en 3 tipos de cirugía: cirugía general (abdominal), el subgrupo de cirugía general para colelitiasis, y cirugía electiva de cadera. Los costos de las complicaciones tromboembólicas y hemorrágicas fueron calculados a partir de las cifras observadas en 28 pacientes hospitalizados en el Departmento de Cirugía. El número de predicción de complicaciones tromboembólicas, y el número de embolismos pulmonares fatales pueden ser minimizados en los 3 tipos de cirugía mediante la profilaxis general. Sin embargo, la profilaxis general con heparina de baja dosis se acompaña de la más alta incidencia de complicaciones hemorrágicas.Los costos de la atención pueden ser minimizados mediante la profilaxis general en cirugía electiva de cadera y en cirugía general abdominal, en tanto que la no profilaxis es la mejor alternativa para la cirugía de colelitiasis.Desde el punto de vista del paciente, la profilaxis general minimiza la duración de la enfermedad tromboembólica en la cirugía general abdominal así como en la cirugía electiva de cadera. En la cirugía para colelitiasis, sin embargo, no se demuestran diferencias entre las dos alternatives principales, no profilaxis y profilaxis general.El tratamiento selectivo significa tratamiento una vez establecido el diagnóstico de trombosis mediante algún método de tamizaje. La alternativa de tratamiento selectivo fue la menos satisfactoria de las 3 alternatives estudiadas.

Résumé Les effets cliniques et financiers de 3 comportements variables: absence de prophylaxie, prophylaxie, traitement sélectif ont été évalué en fonction de trois types de chirurgie: chirurgie générale, chirurgie spéciale de la lithiase biliaire, chirurgie élective de la hanche. Les coûts des complications thrombo-emboliques et hémorragiques ont été calculés à partir des données numériques concernant 28 malades hospitalisés dans le service de chirurgie. Le nombre envisagé des complications thromboemboliques et par conséquent le nombre d'embolie pulmonaire fatale a été réduit dans les 3 types de chirurgie choisis grâce au traitement prophylactique. Cependant il convient de noter que le traitement prophylactique à l'aide de faible dose d'héparine s'accompagne de complications hémorragiques plus nombreuses.Les coûts des soins de la chirurgie élective de la hanche et de la chirurgie générale sont réduits grâce au traitement prophylactique alors que l'absence de traitement prophylactique représente la meilleure modalité à observer dans le traitement de la chirurgie biliaire.En ce qui concerne le point de vue du malade le traitement prophylactique réduit la durée de la maladie thromboembolique compliquant la chirurgie générale ou la chirurgie de la hanche. En revanche dans la chirurgie de la lithiase biliaire aucun inconvénient pour la santé du malade ne s'observe que le traitement prophylactique soit ou ne soit pas appliqué.Le traitement sélectif qui répond au traitement institué après que le diagnostic ait été posé par des méthodes de dépistage est la moins satisfaisante des trois attitudes envisagées.


Supported by grant no. 00759 from the Swedish Medical Research Council.  相似文献   
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