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A genetic epidemiological study of hereditary diseases of the nervous system (HDNS) was conducted in the cities of Volgograd and Volzhsky for the first time. In total, 1 323 500 individuals were examined including the populations of Volgograd and Volzhsky (1 012 800 and 310 700 persons, respectively). The prevalence of neurological diseases with autosomal dominant (AD), autosomal recessive (AR), and X-linked recessive inheritance was estimated. These data were compared with the estimates previously obtained for different population of the Russian Federation. A decrease was found in general HDNS load in Volgograd and Volzhsky. The compared populations were shown to differ in a contribution of AD, AR, and X-linked recessive diseases into the HDNS load formation. The possible effect of population dynamics factors on the HDNS load structure is discussed.  相似文献   

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Summary The presence of dopamine--hydroxylase (DBH) and phenylethanol-amine-N-methyltransferase (PNMT) immunoreactivity in specific neurones of the snail Helix aspersa has been demonstrated. In addition, high performance liquid chromatography and electrochemical detection have revealed the presence of noradrenaline and adrenaline in the snail central nervous system, although the major catecholamine is dopamine. These results suggest that adrenaline, and perhaps noradrenaline, have transmitter or modulatory functions in the snail nervous system.  相似文献   

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Summary Antisera raised against ACTH (1–39), -endorphin and the 16K proopiocortin were used, in association with the immunoperoxidase reaction, to localize positively-staining cell bodies and nerve fibres in the hypothalamus of the rat. Antigens, cross-reactive against anti-ACTH (1–39) serum were detected in a fibre system in the rostro-dorsal hypothalamus situated between the optic chiasm and the third ventricle while immunoreactive 16K-like material was present in fibres localized in the caudal hypothalamus, dorso-lateral to the arcuate nucleus. This latter system was also associated with the appearance of ACTH (1–39) and ACTH (17–39) immunoreactivity.Cells of the arcuate nucleus stained positively for ACTH (1–39), 16K antigen and -endorphin, and on examining adjacent thin sections it was observed that cells that contained 16K antigen-like material, also gave a positive immunoreaction with ACTH (1–39) and -endorphin antisera. In the magnocellular system, cells of the supraoptic (SON) and paraventricular (PVN) nuclei also gave a positive immunoreaction with anti-ACTH (1–39), 16K antigen and -endorphin serum. As in the case of the arcuate nucleus, common cells stained for these three antigens.On the basis of the precursor theory for the synthesis of ACTH, 16K antigen and -endorphin, it was not unexpected to find these three fragments of pro-opiocortin localized together in cells of the arcuate nucleus. That ACTH (1–39), 16K antigen and -endorphin-like materials are present in the magnocellular neurosecretory system would suggest that cells of the SON and PVN are not only involved in the synthesis of neurophysin and the neurohypophysial hormones, but also of some products of the pro-opiocortin molecule. Whether the biochemical nature of the ACTH and -endorphin in cells of the SON and PVN is identical to that of anterior pituitary origin remains to be established, as does the biosynthetic relationship between neurophysin and oxytocin/ vasopressin and these fragments of pro-opiocortin.Drs. M.M. Wilkes, S.S.C. Yen, G. Pelletier, B.A. Eipper and R. Walter are thanked for supplying some of the antisera and antigens used in this study. Thanks also go to Ciba-Geigy Ltd. and Organon Inc. for supplies of ACTH (17–39) and ACTH (1–24) respectively. This work was financed by The Medical Research Council of New Zealand  相似文献   

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By generalizing a previous paper on periodicities in the endocrine system (Bull. Math. Biophysics,30, 735–749, 1968), it is shown that nonperiodic, sporadic oscillations in the system are also possible. A procedure of describing the feedback mechanism between the endocrine system and the central nervous system is suggested. It is shown that the combined system: endocrine—CNS, also may show sporadic fluctuations.  相似文献   

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The epidermal growth factor (EGF) family of polypeptides is regulators for tissue development and repair, and is characterized by the fact that their mature forms are proteolytically derived from their integral membrane precursors. This article reviews roles of the prominent members of the EGF family (EGF, transforming growth factor-alpha [TGF-α] and heparin-binding EGF [HB-EGF]) and the related neuregulin family in the nerve system. These polypeptides, produced by neurons and glial cells, play an important role in the development of the nervous system, stimulating proliferation, migration, and differentiation of neuronal, glial, and Schwann precursor cells. These peptides are also neurotrophic, enhancing survival and inhibiting apoptosis of post-mitotic neurons, probably acting directly through receptors on neurons, or indirectly via stimulating glial proliferation and glial synthesis of other molecules such as neurotrophic factors. TGF-α, EGF, and neuregulins are involved in mediating glial-neuronal and axonal-glial interactions, regulating nerve injury responses, and participating in injury-associated astrocytic gliosis, brain tumors, and other disorders of the nerve system. Although the collective roles of the EGF family (as well as those of the neuregulins) are shown to be essential for the nervous system, redundancy may exist among members of the EGF family.  相似文献   

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The waters of Lagos Harbour have a salinity variation of 30, as a consequence of the annual rainfall regime and of the influx of Atlantic Ocean waters. We made monthly plankton hauls at 10 stations for 11 months starting in October 1986, and found 51 species of rotifers, with Brachionus baylyi Sudzuki & Timms, Keratella hispida Lauterborn, Colurella obtusa Gosse, and Filinia pejleri Hutchinson recorded for the first time in Nigeria. In distribution, species numbers decreased with increasing salinity. Brachionus plicatilis, B. rubens, Hexarthra intermedia, Keratella americana, K. cochlearis and K. tropica were classed as euryhaline. Stenohaline species were Anuraeopsis fissa, Ascomorpha ovalis, Filinia longiseta, F. opoliensis, Gastropus sp., Lecane curvicornis and Monostyla stenroosi. All other monogononts were restricted to waters of salinity below 1.  相似文献   

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 Contrary to traditional views, molecular evidence indicates that the protostomian ventral nerve cord plus apical brain is homologous with the vertebrates’ dorsal spinal cord plus brain. The origin of the protostomian central nervous system from a larval apical organ plus longitudinal areas along the fused blastopore lips has been documented in many species. The origin of the chordate central nervous system is more enigmatic. About a century ago, Garstang proposed that the ciliary band of a dipleurula-type larva resembling an echinoderm larva should have moved dorsally and fused to form the neural tube of the ancestral chordate. This idea is in contrast to a number of morphological observations, and it is here proposed that the neural tube evolved through lateral fusion of a ventral, postoral loop of the ciliary band in a dipleurula larva; the stomodaeum should move from the ventral side via the anterior end to the dorsal side, which faces the substratum in cephalo- chordates and vertebrates. This is in accordance with the embryological observations and with the molecular data on the dorsoventral orientation. The molecular observations further indicate that the anterior part of the insect brain is homologous with the anterior parts of the vertebrate brain. This leads to the hypothesis that the two organs evolved from the same area in the latest common bilaterian ancestor, just anterior to the blastopore, with the protostome brain developing from the anterior rim of the blastopore (i.e. in front of the protostome mouth) and the chordate brain from an area in front of the blastopore, but behind the mouth (i.e. behind the deuterostome mouth). Received: 28 August 1998 / Accepted: 14 November 1998  相似文献   

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《BBA》1987,893(3):452-469
Absorption changes coupled with the individual transitions S0–S3 and redox reactions in the water-splitting enzyme system S of photosynthesis have been measured. The principal difficulties of measuring the very small absorption changes in the ultraviolet coupled with those reactions have been reduced drastically through the use of a highly purified Photosystem II complex isolated from the Cyanobacterium synechococcus. The general problem caused by the mixing of the S states during a train of flashes and the falsification through the overlap with absorption changes of QB (binary oscillations) have been treated as follows. (1) The binary oscillations were bypassed through the use of silicomolybdate and high concentrations of DCBQ, respectively, as external electron acceptor. (2) Stable absorption changes of the mixed S-state transitions have been deconvoluted through fitting procedures to get the changes of the individual transitions of S1 → S2 → S3 → S0 → S1. (3) Kinetically resolved absorption changes of the S-states in the 100-μs range gave independent information on the individual transitions. (4) Stable absorption changes of the S0 → S1 transitions in the forefront were induced after shifting the S states through low concentrations of NH2OH two units backwards. Analysis of the resulting sequence Sx → S0 → S1 → S2 → S3 → S0, beginning with an NH2OH depending pre-state, Sx, and followed by an S0 → S1 transition not mixed with the opposite S3 → S0 transition, increased the conclusiveness considerably. It results that the ultraviolet spectrum of the S0 → S1 transition is different from the spectra of the S1 → S2 and S2 → S3 transition. Possible states of manganese, water and surplus charges responsible for these spectra are presented.  相似文献   

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Summary The central ganglia of the leech,Hirudo medicinalis, were processed for the immunohistochemical localisation of bombesin-, substance P-, cholecystokinin-, vasoactive intestinal polypeptide-, enkephalin-, serotonin- and dopamine--hydroxylase-related substances. To varying extents all of the substances were localised in neuropile processes, and all, with the exception of substance P, were associated with specific perikarya. The most prominent neuropeptides, in terms of the number of immunoreactive neurones, were cholecystokinin and vasoactive intestinal peptide. The dopamine--hydroxylase positive neurones are thought to be octopaminergic, and the serotonin monoclonal antibody revealed positive staining in the Retzius cells. We were unable to demonstrate the coexistence of pairs of substances in any neurones in the leech ganglia.  相似文献   

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Wielkopolska (western Poland) is a region, with good reason, called the main food base of Poland. All indices of agricultural production have always been there (since 19th century) much higher than elsewhere in the country (Ratajczak 1977/1978, Buszko 1984, Gorzelak 1989, Czyzewski et al. 1992; table 1). Such a situation had a beneficial effect on the amount of the income generated by a family of Wielkopolska and, thus, decided on its better financial status. Additionally, rural inhabitants of this region have always been characterised by a more advantageous educational structure in comparison with people of other Polish villages. Generally, it is easy to detect the relationship between the life standard, the level of education and family planning. The aim of this paper is to assess fertility of women from villages of Wielkopolska in the period of transformation of the political and economic system in Poland.  相似文献   

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It is well known that Michaelis–Menten kinetics is suitable for the response function in chemical reaction, when the reaction rate does not increase indefinitely when an excess of resource is available. However, the existing models for insulin therapies assume that the response function of insulin clearance is proportional to the insulin concentration. In this paper, we propose a new model for insulin therapy for both type 1 and type 2 diabetes mellitus, in which the insulin degradation rate assumes Michaelis–Menten kinetics. Our analysis shows that it is possible to mimic pancreatic insulin secretion by exogenous insulin infusions, and our numerical simulations provide clinical strategies for insulin–administration practices.  相似文献   

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Lieber MR  Lu H  Gu J  Schwarz K 《Cell research》2008,18(1):125-133
Nonhomologous DNA end joining (NHEJ) is the primary pathway for repair of double-strand DNA breaks in human cells and in multicellular eukaryotes. The causes of double-strand breaks often fragment the DNA at the site of damage, resulting in the loss of information there. NHEJ does not restore the lost information and may resect additional nucleotides during the repair process. The ability to repair a wide range of overhang and damage configurations reflects the flexibility of the nuclease, polymerases, and ligase of NHEJ. The flexibility of the individual components also explains the large number of ways in which NHEJ can repair any given pair of DNA ends. The loss of information locally at sites of NHEJ repair may contribute to cancer and aging, but the action by NHEJ ensures that entire segments of chromosomes are not lost.  相似文献   

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Wnts comprise a large family of proteins that have shown to be part of a signaling cascade that regulates several aspects of develop- ment including organogenesis, mid brain development as welt as stem cell proliferation. Wnt signaling pathway plays different roles in the development of neuronal circuits and also in the adult brain, where it regulates synaptic transmission and plasticity. It has been also implicated in various diseases including cancer and neurodegenerative diseases, reflecting its relevance in fundamental biological pro- cesses. This review summarizes the progress about Wnts function in mature nervous system with a focus on Alzheimer's disease (AD). We discuss the prospects of modulating canonical and non-canonical Wnt signaling as a strategy for neuroprotection. This will include the potential of Wnts to: (i) act as potent regulators of hippocampai synapses and impact in learning and memory; (ii) regulate adult neurogenesis; and finally (iii) control AD pathogenesis.  相似文献   

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Tonoplast vesicles were prepared from leaf mesophyll homogenates of the crassulacean-acid-metabolism plant Kalanchoë daigremontiana Hamet et Perrier de la Bâthie to study the effects of anions on ATP- and inorganic-pyrophosphate (PPi)-dependent H+ transport. In the presence of gramicidin, substrate hydrolysis by the tonoplast ATPase was characteristically stimulated by chloride and inhibited by nitrate, but was unaffected by malate and a wide range of other organic-acid anions; the PPiase was anion-insensitive. Malate was more effective than chloride both in stimulating ATP- and PPi-dependent vesicle acidification (measured as quinacrine-fluorescence quenching) and in dissipating a pre-existing inside-positive membrane potential (measured as oxonol-V-fluorescence quenching), indicating that malate was more readily transported across the tonoplast. Certain other four-carbon dicarboxylates also supported high rates of vesicle acidification, their order of effectiveness being fumarate malate -succinate > oxalacetate - tartrate; the five-carbon dicarboxylates 2-oxoglutarate and glutarate were also transported, although at lower rates. Experiments with non-naturally occurring anions indicated that the malate transporter was not stereospecific, but that it required the trans-carboxyl configuration for transport. Shorter-chain or longer-chain dicarboxylates were not transported, and neither were monocarboxylates, the amino-acid anions aspartate and glutamate, nor the tricarboxylate isocitrate. The non-permeant anions maleate and tartronate appeared to be competitive inhibitors of malate transport but did not affect chloride transport, indicating that malate and chloride influx at the tonoplast might be mediated by separate transporters.Abbreviations BTP 1,3-bis-[tris(hydroxymethyl)methylamino]-propane - CAM crassulacean acid metabolism - oxonol V bis(3-phenyl-5-oxoisoxazol-4-yl)pentamethine oxonol - pH transmembrane pH difference - PPi inorganic pyrophosphate - PPiase inorganic pyrophosphatase - quinacrine 6-chloro-9-{[4-(diethylamino)-1-methylbutyl]amino}-2-methoxyacridine dihydrochloride - transmembrane electrical potential difference  相似文献   

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