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121.
AIM: To study the antagonism of l-stepholidine (SPD) against bromocriptine (Bro)-inhibition on prolactin (PRL) level. METHODS: Bro (0.5 mg.kg-1.d-1, s.c.) reduced the PRL and caused a dysplasia of mammary gland in lactational rats. The weight growing of newborn rats was retarded. The PRL of the lactational rats was assessed by immunoradiometric assay (IRMA); the weight of newborn rats and development of mammary glands in lactational rats were also examined. Antagonism of SPD was evaluated. RESULTS: SPD (30 & 100 mg.kg-1.d-1, i.p.) obviously antagonized the Bro that induced lowering the PRL level in lactational rats, the PRL was 11 +/- 4 & 23 +/- 6 micrograms.L-1 (NS 7 +/- 2) respectively on d 15 of postpartum and the development of mammary gland in lactational rats was normal. The newborn rats grew rapidly in 11-15 d. CONCLUSION: SPD possessed an antagonism with Bro inhibition on D2 receptors located in the pituitary gland, and was an antagonist of dopamine D2 receptors.  相似文献   
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66 inpatients who met the DSM-III-R and ICD-10 criteria for paranoid schizophrenia-active phase were assessed using the SAPS and CDS in order to establish interrelations between depressive and positive symptomatology. The results were then analyzed in reference do particular items of the scale CDS and the three stages of examinations. Numerous positive correlations were found between depressive symptoms and the symptoms from the subscale of Delusions and Hallucinations SAPS (Delusions of Sin or Guilt, of Mind Reading, of Being Controlled, of Reference, Somatic Delusions and Hallucinations) and negative correlations with the symptoms from the subscale of Positive Formal Thought Disorder.  相似文献   
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Differentiating the binding properties of applied lectins should facilitate the selection of lectins for characterization of glycoreceptors on the cell surface. Based on the binding specificities studied by inhibition assays of lectin-glycan interactions, over twenty Gal and/or GalNAc specific lectins have been divided into eight groups according to their specificity for structural units (lectin determinants), which are the disaccharide as all or part of the determinants and of GalNAc alpha 1-->Ser (Thr) of the peptide chain. A scheme of codes for lectin determinants is illustrated as follows: (1) F (GalNAc alpha 1-->3GalNAc), Forssman specific disaccharide--Dolichos biflorus (DBL), Helix pomatia (HPL) and Wistaria floribunda (WFL) lectins. (2) A (GalNAc alpha 1-->3 Gal), blood group A specific disaccharide--Codium fragile subspecies tomentosoides (CFT), Soy bean (SBL), Vicia villosa-A4 (VVL-A4), and Wistaria floribunda (WFL) lectins. (3) Tn (GalNAc alpha 1-->Ser (Thr) of the protein core)--Vicia villosa B4 (VVL-B4), Salvia sclarea (SSL), Maclura pomifera (MPL), Bauhinia purpurea alba (BPL) and Artocarpus integrifolia (Jacalin, AIL). (4) T (Gal beta 1-->3GalNAc), the mucin type sugar sequences on the human erythrocyte membrane(T alpha), T antigen or the disaccharides at the terminal nonreducing end of gangliosides (T beta)--Peanut (PNA), Bauhinia purpurea alba (BPL), Maclura pomifera (MPL), Sophora japonica (SJL), Artocarpus lakoocha (Artocarpin) lectins and Abrus precatorius agglutinin (APA).(5) I and II (Gal beta 1-->3(4)GlcNAc)--the disaccharide residue at the nonreducing end of the carbohydrate chains derived from either N- or O-glycosidic linkage--Ricinus communis agglutinin (RCA1), Datura stramonium (TAL, Thorn apple), Erythrina cristagalli (ECL, Coral tree), and Geodia cydonium (GCL). (6) B (Gal alpha 1-->3Gal), human blood group B specific disaccharide--Griffonia(Banderiaea) simplicifolia B4 (GSI-B4). (7) E (Gal alpha 1-->4Gal), receptors for pathogenic E. coli agglutinin, Shiga toxin and Mistletoe toxic lectin-I (ML-I) and abrin-a.  相似文献   
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OBJECTIVE: Studies of sex differences in neuropsychological performance in schizophrenia report inconsistent results, due in part to methodological artifacts. The study presented here was specifically designed to examine sex differences in neuropsychological performance. It was hypothesized that schizophrenic women would exhibit fewer neuropsychological deficits than schizophrenic men and that their performance would be more similar to that of normal women than schizophrenic men's performance would be to that of normal men. METHOD: Thirty-one outpatients with DSM-III-R-defined schizophrenia were systematically sampled from an extensive service network serving a large urban catchment area for seriously mentally ill persons. Twenty-seven normal comparison subjects were matched within sex on the basis of age, parental socioeconomic status, ethnicity, and handedness. An extensive neuropsychological test battery was administered, and multivariate analysis of variance was used to test for the effects of sex and group and sex-by-group interactions. RESULTS: Male patients were significantly impaired across all functions in comparison with normal male subjects and on tests of attention, verbal memory, and executive functions in comparison with female patients. Female patients performed significantly worse than female normal comparison subjects only on tests of attention, executive functions, visual memory, and motor functions. CONCLUSIONS: The findings suggest that women with schizophrenia may be less vulnerable to particular cognitive deficits, especially those involving verbal processing, than schizophrenic men.  相似文献   
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Recent data suggesting complex I dysfunction in Parkinson's disease (PD) arises from mitochondrial DNA (mtDNA) mutation does not conclusively answer whether the responsible genetic lesion is inherited (primary) or somatic (secondary). To address this question, we identified a family in which multiple members over three generations are affected with PD through exclusively maternal lines. Cytoplasmic hybrids (cybrids) were created for 15 family members over two generations by transferring each individual's mtDNA to mtDNA-depleted human neuroblastoma cells. Eight of the 15 cybrid lines contained mtDNA obtained from maternally descended family members and seven contained mtDNA from paternally descended family members. After 6 weeks of culture, cybrid cell lines were assayed for complex I activity and oxidative stress, and mitochondrial morphology was analyzed by electron microscopy. Compared with the cybrid lines containing mtDNA from paternal descendants, cybrid lines containing mtDNA from maternal descendants had lower complex I activity, increased reactive oxygen species production, increased radical scavenging enzyme activities, and more abnormal mitochondrial morphologic features. These findings were present in cybrid lines containing mtDNA from maternal descendants with PD as well as in currently asymptomatic young maternal descendants, and support a precedent for inherited mtDNA mutation in some persons with PD.  相似文献   
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To identify epitopes on pilins of Haemophilus influenzae type b (Hib) that may also be immunologically available on assembled pili, antisera were developed against eight synthetic peptides that represent conserved and hydrophilic regions of Hib pilin. Seven of the eight peptides were immunogenic. Binding of the anti-peptide antibodies to purified pili of Hib strain Eagan was weak. However, when the purified pili were denatured by heating, binding of the anti-peptide antibodies improved considerably, suggesting that the epitopes defined by the peptides were more available for anti-peptide antibody binding on the denatured pilins than on purified pili. On Western blot analysis, strain variation was seen in the binding of some of the anti-peptide antibodies, notably those directed against peptides in the N-terminal half of the pilin. Thus, when pilins are assembled into pili, the epitopes defined by the seven immunogenic peptides appear to be altered so that binding of the anti-peptide antibodies is greatly reduced.  相似文献   
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