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101.
The aim of the present study is to investigate the effects of long-term Hypericum perforatum treatment on spatial learning and memory in rats. Hypericum preparation (HP) standardized to 0.3% hypericin content was administered orally for 9 weeks in doses of 4.3 and 13 microg/kg corresponding to therapeutic dosages in humans of 0.3 and 0.9 mg of total hypericins daily. A Morris water maze paradigm was used. The mean escape latency over 4 d for the Control group (21.9 s) and HP 4.3 group (21.7 s) was significantly greater than the latency of the HP 13 group (15.8s). In the probe trial on day 5, the HP 13 group crossed the correct annulus in the SE quadrant more often (4.5) than the other groups: Con (2.4) and HP 4.3 (3.1). After completion of the behavioral experiment, the regional brain concentrations of monoamines and metabolites were estimated in selected brain regions, i.e. prefrontal cortex, hippocampus and hypothalamus. Analysis of variance (ANOVA) demonstrated significant differences in the content of monoamines and metabolites between the treatment groups compared to the Control. The increased 5-hydroxytryptamine (5-HT) levels in the prefrontal cortex correlated positively with the retention of spatial memory. These findings show that the long-term administration of Hypericum perforatum can improve learning and spatial memory with significant changes in the content of monoamines in several brain regions.  相似文献   
102.
Myosin modulates the fibrinolytic process as a cofactor of the tissue plasminogen activator and as a substrate of plasmin. We report now that myosin is present in arterial thrombi and it forms reversible noncovalent complexes with fibrinogen and fibrin with equilibrium dissociation constants in the micromolar range (1.70 and 0.94 microM, respectively). Competition studies using a peptide inhibitor of fibrin polymerization (glycl-prolyl-arginyl-proline [GPRP]) indicate that myosin interacts with domains common in fibrinogen and fibrin and this interaction is independent of the GPRP-binding polymerization site in the fibrinogen molecule. An association rate constant of 1.81 x 10(2) M(-1) x s(-1) and a dissociation rate constant of 3.07 x 10(-4) s(-1) are determined for the fibrinogen-myosin interaction. Surface plasmon resonance studies indicate that fibrin serves as a matrix core for myosin aggregation. The fibrin clots equilibrated with myosin are stabilized against dissolution initiated by plasminogen and tissue-type plasminogen activator (tPA) or urokinase (at fibrin monomer-myosin molar ratio as high as 30) and by plasmin under static and flow conditions (at fibrin monomer-myosin molar ratio lower than 15). Myosin exerts similar effects on the tPA-induced dissolution of blood plasma clots. Covalent modification involving factor XIIIa does not contribute to this stabilizing effect; myosin is not covalently attached to the clot by the time of complete cross-linking of fibrin. Thus, our in vitro data suggest that myosin detected in arterial thrombi binds to the polymerized fibrin, in the bound form its tPA-cofactor properties are masked, and the myosin fibrin clot is relatively resistant to plasmin.  相似文献   
103.
INTRODUCTION: The screening mammography decreases the mortality of female breast cancer. METHODS: A complex, independent centre of screening mammography has been operating in Debrecen since 1999. RESULTS: The number of the examinations were 10,399 in 1999 and 13,800 in 2000. The number of explored breast cancer cases were 43 (0.41%) in 1999 and 62 (0.45%) in 2000. CONCLUSION: Although the mortality reduction can be exactly measured after several years, we are convinced that the chances for a better life of these 107 women operated on with breast cancer in early state increased thanks to our project. The results of the breast cancer screening program in Debrecen fulfilled the professional requirements of mammographic service-screening.  相似文献   
104.
Earlier findings have shown that after unification with the Federal Republic of Germany (FRG) in October 1990 the proportion of very-low-birthweight infants in the former German Democratic Republic (GDR) increased. This study seeks to explore this observation in more detail at the regional level. The analysis of aggregate data of live births in Germany between 1991 and 1997 shows an increasing proportion of very-low-birthweight infants as well as a general trend towards heavier babies in both east and west. The growing proportion of live born infants at very low birthweights in the east, however, seems to be due, in part, to increased registration, most likely reflecting the introduction of the more comprehensive (western) definition of a live birth with unification in October 1990. A fairly distinct east-west pattern in the birthweight distribution present in 1991 had almost disappeared by 1997 and given way to a north-south one.  相似文献   
105.
Today's global health crisis illustrates many of the transnational governance challenges the United States faces today. In the arena of global health, the United States can create a new role for itself by moving beyond a national-interest paradigm and strengthening its "soft power" position in health. Health in recent administrations has moved beyond being "just" a humanitarian issue to being one with major economic and security interests. Despite U.S. unilateralism, new approaches to global health governance are being developed by other actors, who have influenced the U.S. agenda and made important contributions. Yet a larger leader is still needed, especially in identifying and following a sound legal and regulatory global health governance system; bringing political legitimacy; and setting priorities. Responsible political action is needed to develop a new mindset and lay the groundwork for better global health in the future.  相似文献   
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107.
Life-threatening, complete middle cerebral artery infarction occurs in up to 10% of all stroke patients. The "malignant media occlusion" is an infarction occupying more than 50% of middle cerebral artery territory. The malignant, space-occupying supratentorial ischemic stroke is characterised by a mortality rate of up to 80%. Several reports indicate, that hemicraniectomy in this situation can be life-saving. Hemicraniectomy increases cerebral perfusion pressure and optimises retrograde perfusion via the leptomeningeal collateral vessels. A case of a patient is presented, having progressive neurological deterioration due to massive cerebral infarctions. The patient rehabilitation was successful. Decompressive surgery is life saving and can also give acceptable functional recovery. Hemorrhagic stroke is due to stroke in 15% of cases and in 10%, it is "spontaneous" intracerebral hematoma. The intracerebral and intraventricular hemorrhage represents one of the most devastating types of stroke associated with high morbidity and mortality. The 30-day mortality rate is 35% to 50% and most survivors are left with a neurological disability. The value of surgical therapy is debatable. The aspiration and urokinase therapy of the hematoma of intracerebral hemorrhage could improve final neurological outcome. Spontaneous, nontraumatic intraventricular hemorrhage frequently carries a grave prognosis. A large part of morbidity after intraventricular hemorrhage is related to intracranial hypertension from hydrocephalus. One patient presented had intracerebral hemorrhage and another had intraventricular hemorrhage treated with urokinase. Rapid and extensive reduction in the amount of intracerebral and intraventricular blood occurred. Urokinase lysis is safe and can be a potentially beneficial intervention in intracerebral and intraventricular hemorrhage. By performing decompressive craniectomy, the neurologists of stroke departments and intensive care units with the neurosurgeons will have to play major role in the management of stroke patients.  相似文献   
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110.
Prognostic value of exercise test in evaluation of cardiac events were examined in 326 pts after coronary artery bypass grafting (CABG). During 6 years follow up 18 (5.5%) cardiac deaths and 23 (7.1%) myocardial infarctions were observed. Chest pains persisted in 116 pts (35.6%) and 37 (11.3%) pts needed hospital treatment. Coronary and bypass angiography were performed in 25 pts (7.7%) followed by PTCA in 8 pts (2.5%) and CABG in 5 (1.5%) pts. Exercise duration and maximal work capacity in exercise tests were significantly lower in pts with cardiac events. Reasons of exercise termination: ST segment depression, heart rate and blood pressure values were not different in pts with and without cardiac events and didn't have prognostic value. Patients with cardiac events had significantly reduced left ventricle function. The value of ejection fraction influenced significantly relative risk of cardiac death (p < 0.05).  相似文献   
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