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Summary In the elasmobranch fish, Scyllium stellare, a complex group of cells protrudes into the cavity of the mesencephalic ventricle of the optic tectum. It consists of six to seven large spherical perikarya which resemble neurons of the mesencephalic nucleus of the Vth cranial nerve. The bundled processes of these cells form a stalk connecting the protrusion with the brain tissue. The protrusion is located in the region where the mesencephalic ventricle joins the cerebral aqueduct. This complex was not found in all specimens examined in the present study. The functional role of this peculiar group of cells, which contain dense core granules and are bathed in the cerebrospinal fluid, is open to discussion.  相似文献   
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The ligands 1,3-bis(3-pyridyl)benzene (1), 1,3-bis(4-pyridyl)benzene (2) and 1,3,5-tris(4-pyridyl)benzene (3) have been prepared by Stille coupling of 3- or 4-trimethylstannylpyridine with the appropriate bromoarene. Ligands 1 and 2 react with [M(OTf)2(dppp)] (M=Pd, Pt) to produce the dipalladium- or diplatinum-containing macrocycles [M2(μ-1)2(dppp)2](OTf)4 or [M2(μ-2)2(dppp)2](OTf)4. These have been characterized by NMR spectroscopy and mass spectrometry and, in the case of [Pd2(μ-1)2(dppp)2](OTf)4, by X-ray crystallography. The molecular structure of the [Pd2(μ-1)2(dppp)2]4+ cation reveals a shallow arrangement of the aromatic rings, with the palladium atoms lying above and below. The tridentate ligand 3 reacts with [Pd(OTf)2(dppp)] to produce a trimetallic species of the form [Pd33-3)2(dppp)3](OTf)6.  相似文献   
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Antidepressants are widely used in the treatment of mood disorders associated with dementia, however little information is available on their effect at the molecular level. In certain neurodegenerative disorders, such as in Alzheimer's disease, lymphocytes have been used to assess mirror changes that thought to occur in the brain. Gene expression profiles of lymphocytes from Alzheimer patients have been shown to differ from that seen with controls. To address this issue in light of antidepressant treatment, we used lymphocytes derived from Alzheimer's disease patients and control individuals to assess the impact of the selective serotonine reuptake inhibitor citalopram on gene expression using a cDNA microarray representing 3200 distinct human genes. Sequences that are differentially regulated after treatment with citalopram were identified and categorized based on similarities in biological functions. This analysis revealed that the overexpression of genes in control and Alzheimer white blood cells by citalopram are implicated in cell survival. Apart from this, citalopram did not markedly alter genes involved in other molecular functions in control cells. In contrast, alteration of genes implicated in ionic currents, cell-adhesion, immune mechanism, and adrenergic functions, were also observed in Alzheimer lymphocytes. The expression of genes of Alzheimer lymphocytes by citalopram is modulated differently which may correlate with the pathology.  相似文献   
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We investigated the effects of body fat content on mouse fecundity, ovarian hormone release, and their response to follicle stimulation hormone (FSH). 4 types of females were produced: lean (group 1), normal (group 2), slightly fat (group 3), and significantly fat (group 4). The body weights, fat content, fertility rate, embryo number produced, retarded and degenerated embryo percentage, the release of progesterone (P4), testosterone (T), and insulin-like growth factor I (IGF-I) by isolated ovaries cultured with and without FSH (1.0 IU/mL medium) were evaluated. A gradual increase in body weight and fat contents from groups 1 to 4 was observed. Group 2 had higher fertility rate than those from the other groups. Groups 2 and 3 had fewer retarded and degenerated embryos that those from groups 1 and 4. Embryo production rate was not different among the groups. P4 and T secretion was higher from group 4 than in those from groups 1–3; secretion of IGF-I of group 3 was less than that of groups 1, 2, and 4. FSH promoted ovarian T output in all groups and stimulated ovarian P4 release in groups 1, 3, and 4, but not in group 2. FSH did not affect IGF-I release in any group. Therefore, both malnutrition and overfeeding can affect body weight and fat content in female mice, reducing embryo quality or developmental capacity, but not fertility and embryo production. Excess weight or fat can have stimulatory effects on ovarian P4 and T, but inhibitory effects on ovarian IGF-I release. Both leanness and excess weight or fat can induce the stimulatory action of FSH on ovarian P4.  相似文献   
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