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71.
We studied NK cell function in eight patients with pathological hyperprolactinemia by measuring51Cr release by K562 cells exposed to their mononuclear cells and found it decreased compared to normal controls (P<0.01). Bromocriptine (BrC) treatment corrected NK function but also made it more efficient at 12:1 than at 25:1 or 50:1 effector:target ratios (ANOVA;P=0.01). The study of NK cell function in agarose revealed that its decrease in hyperprolactinemia is due to their low active binding to target cells, active killing, and recycling capacity. BrC tended to correct them but also increased recycling capacity to levels higher than those of controls (P<0.05). Sequential studies in three hyperprolactinemic patients before and after BrC showed correction of NK function within 1 week but its increased efficiency at the 12:1 effector:target ratio required 8 weeks. We conclude that hyperprolactinemia decreases NK cell function. BrC corrects this by decreasing prolactin levels but also makes NK function more efficient by increasing the capacity of NK cells to recycle after killing.  相似文献   
72.
目的 探讨碘伏清洗外耳道的效果。方法 将耳部疾病患者100例(127耳)随机分为观察组和对照组各50例,观察组采用0.5%碘伏液清洗外耳道,对照组采用3%过氧化氩液清洗外耳道。两组其他操作方法相同。结果 两组治疗效果比较,差异无显著性意义(P〉0.05),但观察组外耳道清洗后耳痛发生率显著低于对照组(P〈0.01)。结论 0.5%碘伏液清洗外耳疗效较好,对皮肤黏膜无刺激,可减轻患者痛苦,是比较满意的外耳道洗耳液。  相似文献   
73.
Objectives:  Bipolar disorder is a severe illness that is associated with suicidal behavior. A biological predictor of highly lethal suicide attempts in patients with bipolar disorder would be valuable. We hypothesized that cerebrospinal fluid (CSF) monoamine metabolite levels are related to lethality of suicide attempts in bipolar patients and examined the relation between CSF 5-hydroxyindolacetic acid (5-HIAA), homovanillic acid (HVA), and 3-methoxy-4-hydroxyphenylglycol (MHPG) levels and maximum lethality of suicide attempts at baseline and during a 2-year follow up.
Methods:  Twenty-seven bipolar depressed patients participated in the study. Demographic and clinical parameters were examined and recorded. Lumbar punctures were performed and CSF 5-HIAA, HVA, and MHPG were assayed by high-performance liquid chromatography with electrochemical detection. Following discharge, patients were evaluated after 3 months, 1 year, and 2 years. Each follow-up interview included an in-depth assessment of suicidal behavior during the intervening time period.
Results:  Six subjects made suicide attempts during the 2-year follow-up. Bipolar patients who attempted suicide during the follow-up period had higher aggression and hostility scale scores compared to bipolar subjects who did not make a suicide attempt during the follow-up period. CSF 5-HIAA, HVA, and MHPG levels were negatively correlated with the maximum lethality of suicide attempts during the 2-year follow-up period.
Conclusions:  Our finding is the first observation that CSF monoamine metabolite levels may be predictors of lethality of suicide attempts in patients with bipolar disorder. Further studies are necessary to answer the question whether CSF monoamine metabolite levels are clinically useful biochemical predictors of highly lethal suicide attempts or completed suicides.  相似文献   
74.
75.
The present work tries to establish the antioxidant capacity of the peripheral nervous tissue of the rat, in terms of the enzymatic activities present in this tissue that either prevent the formation of activated species as the semiquinone radical (DT-diaphorase), protect against activated oxygen species (superoxide dismutase, glutathione peroxidase), conjugate natural toxic products or xenobiotics (glutathione S-transferases, especially the activity conjugating 4-hydroxy-nonenal), or complete the glutathione system metabolism (glutathione disulfide reductase, γ-glutamyl transpeptidase). All the activities studied are lower in this tissue than they are in liver, except for γ-glutamyl transpeptidase. The relevance of the results obtained and its possible relationship with different neuropathies is discussed. It is concluded that the peripheral nervous tissue is by far less protected than the liver against oxidative damage.  相似文献   
76.
Melatonin reduces nitric oxide synthase activity in rat hypothalamus   总被引:2,自引:0,他引:2  
Abstract: In this report, rat hypothalamic nitric oxide synthase (NOS) activity is shown to be partially inhibited by physiological concentrations of the pineal hormone melatonin. In vitro studies demonstrate that 1 nM melatonin, which approximates the physiological concentration of the hormone at night, significantly inhibited NOS activity. In vivo studies show that administering melatonin or collecting the hypothalamus from animals at night, when endogenous melatonin levels are elevated, results in a significant decrease of NOS activity. Results also show that calmodulin may be involved in this process since its presence in the incubation medium prevents the inhibitory effect of melatonin on NOS activity.  相似文献   
77.
78.
Immunology     
A selection of interesting papers that were published in the two months before our press date in major journals most likely to report significant results in immunology.  相似文献   
79.
Quantitative receptor autoradiography was used to study possible alterations of the densities of multiple serotonin (5-HT) receptor subtypes and of serotonin transporter in the brain of 5-HT(2C) receptor knockout mice. The radioligands employed were [(3)H]citalopram, [(3)H]WAY100,635, [(3)H]8-OH-DPAT, [(3)H]GR125743, [(3)H]sumatriptan, [(3)H]MDL100,907, [(125)I](+/-)DOI, [(3)H]mesulergine, [(3)H]5-HT, [(3)H]GR113808, and [(3)H]5-CT. As expected, radioligands that label 5-HT(2C) receptors showed a complete absence of labeling in mutant mice choroid plexus and significantly reduced densities in other brain regions expressing 5-HT(2C) receptors. With the rest of the radioligands, no significant alterations in the densities of labeled sites were found in any brain region. In situ hybridization showed no changes in 5-HT(2A) receptor and serotonin transporter mRNA levels, whereas 5-HT(2C) receptor mRNA levels were reduced in certain brain regions. The present results indicate that the mouse serotonergic system does not exhibit compensatory up- or down-regulation of the majority of its components (serotonin transporter and most 5-HT receptor subtypes) in response to the absence of 5-HT(2C) receptors.  相似文献   
80.
Patients treated for sporadic and hereditary medullary thyroid carcinoma (MTC) have varying rates of persistent disease, recurrence, and survival. The aim of this study was to correlate the immunoreactivity of the monoclonal antibody CD15 (LeuM1) to initial clinical findings and the outcome of treatment. The primary tumors of 75 patients with sporadic MTC, 7 with hereditary disease, and 3 members of MEN 2A families were studied. Of these subjects 74 (87%) showed no or little immunoreactivity (<15% positive cells; score 0) in most tumors. The remaining 13% had surgery for tumors with more than 15% cells with positive staining (score I). There was no correlation between LeuM1 immunoreactivity and sex, age, and type of MTC. There was, however, a significant correlation with the pTNM classification and UICC staging. The prognosis for patients with score 0 was significantly better than score 1 patients. CD15 immunoreactivity appears to be a predictive factor in sporadic and hereditary MTC. Lymph node dissection seems to be more successful in patients with score 0 tumors than in those with score 1 tumors. The question of reoperation in patients with recurrence of disease (especially with biochemical recurrence or persistence) should be discussed on the basis of CD15 immunoreactivity.
Resumen Los pacientes tratados para carcinoma medular, esporádico y hereditario, de la glándula tiroides (CMT) exhiben grandes variaciones en las tasas de enfermedad persistente, recidiva y sobrevida. El propósito del presente estudio fue establecer la correlación entre la inmunorreactividad del anticuerpo CD15 (LeuM1) y los hallazgos clínicos iniciales, así como con el resultado final del tratamiento.Se estudiaron los tumores primarios de 75 pacientes con CMT esporádico, de siete con enfermedad hereditaria y de 3 miembros de familias con síndrome NEM2A.Setenta y cuatro pacientes (87%) exhibieron ninguna o muy baja inmunorreactividad (menos de 15% de células positivas; puntaje 0) en la mayoría de los tumores. El 13% restante fue sometido a cirugía por tumores con más de 15% de las células con coloración positiva (puntaje 1). No se evidenció correlación entre la inmunorreactividad LeuM1 y el sexo, edad o tipo del CMT. Sin embargo, sí apareció una correlación significativa con la clasificiación pTNM y la estadificación de la UICC. El pronóstico de los pacientes con puntaje 0 resultó significativamento mejor que el de los pacientes con puntaje 1.La inmunorreactividad CD15 parece ser un factor de predicción de pronóstico en el CMT esporádico y familiar. La disección ganglionar parece ser más exitosa en pacientes con tumores de puntaje 0 que en los que portan tumores con puntaje 1.El interrogante en cuanto a reoperación en pacientes con recidiva de la enfermedad (especialmente cuando hay recidiva o persistencia bioquímica) debe ser considerada con base en la inmunorreactividad CD15.

Résumé Les taux de maladie persistante, de récidive et de survie chez des patients traités pour cancer médullaire sporadique et héréditaire de la thyroïde (CMT) sont très variables. Le but de cette étude a été de corréler l'immunoréactivité des anticorps monoclonaux CD15 (LeuM1) à des données cliniques initiales et l'évolution finale du traitement des CMT. On a étudié 75 patients ayant un CMT primitif, sept ayant une maladie héréditaire, et trois membres d'une famille MEN 2A. Soixante quatre patients (87%) avaient peu ou pas d'immunoréactivité (moins de 15% de cellules positive: score = 0). Les 13% restants ont eu une chirurgie pour les tumeurs ayant un pourcentage > 15 (score = 1). Il n'y avait aucune corrélation entre l'immunoréactivité LeuM1 et le sexe, l'âge et le type de CMT. Il y avait, en revanche, une corrélation significative entre la classification pTMN et le stage UICC. Le pronostic des patients ayant un score = 0 était significativement meilleur que celui des patients ayant un score = 1. L'immunoréactivité CD15 apparaît comme étant un facteur pronostique des CMT. Le curage lymphatique


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