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31.
Summary An exotoxin of Bacillus thuringiensis known to inhibit adenylate cyclase in vitro has been used to investigate the role of cyclic AMP in the pathogenesis of fever in the rabbit. Intra-hypothalamic microinjections of the exotoxin are non-pyrogenic and significantly attenuate the hyperthermia caused by intrahypothalamic microinjections of both bacterial pyrogen (endotoxin) and prostaglandin E1. The hyperthermia produced by dibutyryl cyclic AMP is not affected by the exotoxin. These results support the idea that adenylate cyclase is activated during the development of fever in the rabbit.  相似文献   
32.
  1. Adrenomedullin (ADM) is a recently characterized circulating hormone which affects haemodynamic, renal and pituitary function in mammals. We have shown previously that in sheep, ADM produces vasodilatation together with increases in cardiac output and contractility. However, whether these effects are direct or mediated by autonomic reflexes is unclear. The present study examined the cardiovascular actions of an intravenous infusion of ADM in conscious, chronically instrumented sheep with either sympathetic, parasympathetic or autonomic ganglion blockade, to determine the role of the autonomic nervous system in mediating these cardiovascular changes.
  2. Human ADM (1–52) was infused for 60 min at 2 μg kg−1 h−1 following: (1) saline control, (2) combined α/β-adrenoceptor (sympathetic) blockade (proporanolol 0.4 mg kg−1 h−1+phentolamine 0.15 mg kg−1 h−1 for 20 h), (3) muscarinic (parasympathetic) blockade (methscopolamine 0.05 mg kg−1 h−1 for 20 h) or (4) ganglion blockade (hexamethonium 3 mg kg−1 h−1 for 4 h). Measurements were made of mean arterial pressure (MAP), heart rate (HR), cardiac output (CO), stroke volume (SV), total peripheral conductance (TPC), maximal aortic flow (Fmax) and maximal rate of change of aortic flow (dF/dt).
  3. ADM reduced MAP by 3±1 mmHg, and increased CO (1.2±0.2 l min−1), HR (14±2 beats min−1), TPC (21±3 ml min−1 mmHg−1), Fmax (2.3±0.8 l min−1) and dF/dt (86±21 l min−1 s−1) in normal sheep. In animals with α/β blockade, similar changes were observed with ADM. However, during muscarinic blockade, the increases in HR (32±4 beats min−1), CO (2.1±0.4 l min−1), TPC (31±4 ml min−1 mmHg−1), Fmax (4.0±0.6 l min−1), and dF/dt (150±12 l min−1 s−1) produced by ADM were enhanced. During ganglion blockade, ADM produced a greater reduction in MAP (−10±2 mmHg) compared to controls (−3±1 mmHg). However, there was no increase in HR. The changes in CO, TPC and contractility were similar to those observed in control animals.
  4. These results suggest that the vasodilator effects of ADM on the periphery and its ability to increase CO and cardiac contractility are not mediated by the autonomic nervous system, but are probably the result of direct actions of ADM on the heart and vasculature.
  相似文献   
33.
  1. Differentiated HL60 cells have been utilized as a model system to examine the ‘priming'' of neutrophil phospholipase A2 activity. In control cells activation of phospholipase A2 by a 5 min stimulation with the chemotactic peptide formyl-methionyl-leucyl-phenylalanine (100 nM) was essentially undetectable. When cells were primed by preincubation with 5 μM cytochalasin B for 5 min arachidonate release, a measure of phospholipase A2 activation, was observed within 20 s.
  2. Priming by cytochalasin B did not involve or require a change in intracellular free calcium concentration.
  3. Priming was associated with an increase in general protein tyrosine phosphorylation and could also be induced by the receptor tyrosine kinase agonist granulocyte macrophage colony-stimulating factor (GM-CSF, 20 ng ml−1) and be mimicked by treatment with the phosphotyrosine phosphatase inhibitor perhydrovanadate (0.5 mM). However, an increase in MAP kinase activity was not involved in the priming process.
  4. Western blot analysis demonstrated that phospholipase A2 was phosphorylated in both control and primed cells, but that an increase in the amount of membrane associated enzyme was found in the primed cells.
  5. Thus priming appears to be due to membrane association of the phospholipase and this may be regulated by tyrosine kinase activities.
  相似文献   
34.
35.
This study compared parent-reported competencies and behavioral/emotional problems in demographically-matched samples of Greek and American children, ages 6–11. Parents of 356 children of each nationality completed the Child Behavior Checklist (CBCL). Competence scores were higher for American children, except on Academic Competence, where scores were higher for Greek children. Greek scores were significantly higher than American scores on the Withdrawn, Anxious/Depressed, Attention Problems, Delinquent Behavior, Aggressive Behavior, Internalizing, Externalizing, and Total Problem scales. On the Anxious/Depressed syndrome, nationality accounted for 14% of the variance. There were few main effects for sex and age and fewer interactions. The higher problem scores in the Greek sample were partly due to the tendency of Greek parents to use extreme item scores. When items were scored present v. absent, Greek scores were higher only on Withdrawn, Anxious/Depressed, Internalizing, and Total Problems, while American scores were higher on Somatic Complaints and Thought Problems. Nationality differences in rates of referral for mental health services and sample differences in exclusion criteria for prior mental health services may have contributed to differences in problem scores. Results are compared to findings from other cross-cultural studies.
Zusammenfassung Diese Studie vergleicht die Fähigkeiten und Verhaltens- bzw. emotionalen Auffälligkeiten in demographisch parallelisierten Stichproben von griechischen und amerikanischen Kindern im Alter von 6-11 Jahren. Die Eltern von 356 Kindern der beiden Nationalitäten füllten die Child Behavior Checklist (CBCL) aus. Die Kompetenzwerte waren bei den amerikanischen Kindern mit Ausnahme der akademischen Fähigkeiten höher. Die griechischen Werte waren signifikant höher als die amerikanischen im Hinblick auf die Skalen Zurückhaltung, ängstlich/depressiv, Aufmerksamkeitsstörungen, delinquentes Verhalten, aggressives Verhalten, Internalisation, Externalisation und Gesamtauffälligkeiten. Im Hinblick auf das ängstlich/depressive Syndrom war die Nationalität für 14% der Varianz verantwortlich. Nur vereinzelt wurden Haupteffekte im Hinblick auf Geschlecht und Alter und eine geringere Anzahl Interaktionen festgestellt. Die höheren Problemwerte in der griechischen Stichprobe waren teilweise durch die Tendenz der griechischen Eltern bedingt, extreme Werte anzukreuzen. Bei den Items, die als vorhanden bzw. nicht vorhanden gewertet werden mußten, waren die griechischen Werte nur bei den Skalen Zurückhaltung, ängstlich/depressiv, Internalisation und Gesamtprobleme höher, während amerikanische Werte für die Skalen körperliche Beschwerden und Denkstörungen höher lagen. Nationalitätsunterschiede der Zuweisungsraten zu psychosozialen Diensten und Stichprobenunterschieden im Hinblick auf die Ausschlußkriterien für vorangegangene Inanspruchnahme psychosozialer Dienste könnten zu den unterschiedlichen Problemwerten beigetragen haben. Die Ergebnisse werden verglichen mit anderen transkulturellen Studien.

Résumé Cette étude a comparé les compétences et les problèmes de comportement et affectifs rapportés par les parents d'un échantillon d'enfants grecs et américains âgés de 6 à 11 ans appariés démographiquement. Les parents de 356 enfants de chaque nationalité ont rempli la Child Behavior Checklist (CBCL). Les scores de compétence étaient plus élevés pour les enfants américains excepté pour la compétence scolaire pour laquelle les scores étaient plus élevés chez les enfants grecs. Les scores grecs étaient significativement plus hauts que les scores américains quant au retrait, l'anxiété-dépression, les problèmes d'attention, le comportement délinquant, le comportement agressif, les échelles d'internalisation, d'externalisation et de problèmes totaux. Pour le syndrome anxiodépressif, la nationalité intervenait pour une variance de 14%. Il y avait peu d'effets principaux en ce qui concerne le sexe et l'âge. Les scores de problèmes les plus élevés dans les échantillons grecs étaient en partie dûs à la tendance des parents grecs à utiliser des items extrêmes. Quand les items étaient cotés présents versus absents, les scores grecs étaient plus élevés seulement en ce qui concerne le retrait, l'anxiété-dépression, l'internalisation et les problèmes totaux tandis que les scores américains étaient plus hauts en ce qui concerne les plaintes somatiques et les problèmes de pensée. Les différences de nationalité en ce qui concerne les taux de référence à des services de santé mentale et les différences des échantillons dans les critères d'exclusion pour l'utilisation antérieure de services de santé mentale, peuvent avoir contribué aux différences dans les scores de problèmes. Les résultats sont comparés aux autres études transculturelles.
  相似文献   
36.
Chromosome 11q13 markers and D-type cyclins in breast cancer   总被引:7,自引:0,他引:7  
Summary One in six primary human breast cancers has DNA amplification centered on the cyclin D1 gene (CCND1) on chromosome 11q13. This genetic abnormality is preferentially associated with estrogen-receptor positive tumors and may define a sub-class of patients with an adverse prognosis. AlthoughCCND1 has the credentials of a cellular oncogene, being a target for chromosomal translocation and retroviral integration, the 11q13 amplicon encompasses several other markers andCCND1 is not the only candidate for the key gene on the amplified DNA. To assess their relative importance, we have constructed a physical map of the amplified DNA and compared the extent and frequency of amplification across the region. Since it is likely that the gene providing the selective force for amplification will be expressed at elevated levels, we have also examined expression of both RNA and protein. By these criteria, cyclin D1 remains the strongest candidate for the key oncogene on the amplicon and we are currently investigating the functional consequences of its over-expression.Presented by Gordon Peters at the 16th Annual San Antonio Breast Cancer Symposium, San Antonio TX, USA, November 4, 1993; Minisymposium on Molecular Genetics in Breast Cancer.  相似文献   
37.
Intra-anal intussusception was diagnosed in eight of 39 patients on evacuation proctography. Posteroanterior views revealed prolapse of the infolded rectum into the anal canal on straining in seven of eight patients, associated with splaying open of the anal canal and sudden distal movement of the fold during prolapse. Similar changes were seen in four of 31 patients in whom intussusception had not been diagnosed on lateral evacuation proctography. The pattern of the collapsed rectum was assessed for fold length, thickness, and angulation in relation to the midline of the rectum. Infoldings that prolapsed were closer to the anorectal junction on stress (mean 14.6 42.4 mm, p < 0.0001) showed greater change in height between rest and strain (28.8 14.6 mm, p < 0.05) and became more acutely angled during straining (41.9 5.3°, p < 0.01). Intra-anal intussusception may be missed in 33% (four of 12 patients) on routine evacuation proctography. Posteroanterior stress proctography is a simple supplementary examination to validate intussusception.  相似文献   
38.
Multiple endocrine neoplasia type I (MEN-I) is an autosomal dominant disorder characterized by endocrinopathies involving the anterior pituitary gland, parathyroid glands, and pancreas. The long-term prognosis for patients affected with this disorder is uncertain. To better characterize this prognosis, we performed a retrospective review of all patients with MEN-I treated at a single institution during the period 1951–1997. A group of 233 patients served as the study population. Their records were analyzed for confirmation of diagnosis, treatments received, long-term survival, and cause of death. Altogether, 108 eight male patients (46%) and 125 female patients (54%) were identified. At the conclusion of the study, 164 (70%) were alive and 69 (30%) were deceased, with a median follow-up for patients alive at last contact of 13.4 years (range < 1 month to 54.3 years). The cause of death was reliably obtained in 60 patients. Of these patients, 17 (28%) died of causes related to MEN-I, most commonly metastatic islet cell tumors (10 patients). The remaining patients died of causes unrelated to MEN-I, most commonly coronary artery disease and nonendocrine malignancies (14% each). The overall 20-year survival of MEN-I patients was 64% (95% CI was 56–72%), and that of an age- and gender-matched upper Midwest population was 81% (p < 0.001). Patients with MEN-I appear to be at increased risk of premature death. Earlier diagnosis and treatment of potentially malignant pancreatic islet cell neoplasms may result in a decrease of this premature mortality.  相似文献   
39.
目的 建立一种快速有效的分析方法 ,达到鉴定淫羊藿及人参复方产品中黄酮苷类及人参皂苷类成分 ,并测定各成分含量的目的 ,最终控制复方中淫羊藿及人参的比例。方法 通过反相液相色谱 ,对包括药典所收载的淫羊藿药材及其产品进行分析。淫羊藿中的主要黄酮苷类成分 ,以淫羊藿定A、淫羊藿定B、淫羊藿定C、淫羊藿苷为对照品 ;对主要的人参皂苷类成分 ,以人参皂苷Rg1 、Re、Rf、Rb1 、Rb2 、Rd为对照品。结果 在同一色谱条件下 ,对主要黄酮苷类及人参皂苷类成分均可同时测定且分离良好。结论 该方法适用于淫羊藿、人参及其复方产品中淫羊藿黄酮苷类、人参皂苷类成分的定性、定量分析  相似文献   
40.
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