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991.
Lars O. E. Ebbesson Bo Holmqvist Thomas Östholm Peter Ekström 《Cell and tissue research》1992,268(2):389-392
Summary In coho salmon (Oncorhynchus kisutch), smolt transformation has been shown to be associated with sequential surges of neurotransmitters in the brain. In order to determine if the surge of serotonin (5-HT) is correlated with structural changes, we have used immunocytochemistry to observe changes in the serotonin immunoreactivity before, during and after the 5-HT surge. The following stages were studied: 12-month-old freshwater presmolts, 17-month-old freshwater presmolts, 18-month-old saltwater smolts, 19-month-old saltwater postsmolt, 24-month-old postsmolt, and adult spawners. In the 17-month-old samples, but not at any other stage, we found a set of transient (serotonin-immunoreactive) 5-HT-immunoreactive neurons in the lateral preoptic area, as well as a discrete population of 5-HT-immunoreactive neurons in the lateral part of the dorsal right habenular nucleus. In addition, a higher density of serotonergic fibers was found in the telencephalon at this stage compared to the following two stages. Since the transient 5-HT-immunoreactive structures presented here do not appear simultaneously with the 5-HT total brain concentration surge, we conclude that they are unlikely to be the source of the 5-HT surge, but are probably related to other developmental changes in the brain associated with smolt transformation. 相似文献
992.
Cihan Öner Aleksandar J. Dimovski Nancy F. Olivieri Gino Schiliro John F. Codrington Sladdehine Fattoum Adekunle D. Adekile Reyhan Öner Gunes T. Yüregir C. Altay A. Gurgey Rashik B. Gupta Vinod B. Jogessar Michael N. Kitundu Dimitris Loukopoulos Gabriel P. Tamagnini M. Leticia S. Ribeiro Ferdane Kutlar Li-Hao Gu Kenneth D. Lanclos Titus H. J. Huisman 《Human genetics》1992,89(1):99-104
Summary We have determined the s haplotypes in 709 patients with sickle cell anemia, 30 with SC disease, 91 with S--thalassemia, and in 322 Hb S heterozygotes from different countries. The methodology concerned the detection of mutations in the promoter sequences of the G- and A-globin genes through dot blot analysis of amplified DNA with 32P-labeled probes, and an analysis of isolated Hb F by reversed phase high performance liquid chromatography to detect the presence of the AT chain [A75 (E19) IleThr] that is characteristic for haplotype 17 (Cameroon). The results support previously published data obtained with conventional methodology that indicates that the s gene arose separately in different locations. The present methodology has the advantage of being relatively inexpensive and fast, allowing the collection of a vast body of data in a short period of time. It also offers the opportunity of identifying unusual s haplotypes that may be associated with a milder expression of the disease. The numerous blood samples obtained from many SS patients living in different countries made it possible to compare their hematological data. Such information is included (as average values) for 395 SS patients with haplotype 19/19, for 2 with haplotype 17/17, for 50 with haplotype 20/20, for 2 with haplotype 3/3, and for 37 with haplotype 31/31. Some information on haplotype characteristics of normal A chromosomes is also presented. 相似文献
993.
It is argued that in order to optimize the achievement of self-control and to evaluate the clinical effects of biofeedback three skills should be included in training and assessment, namely: (1) the ability of voluntary control with external feedback, (2) the ability of voluntary controlwithout external feedback, and (3) the ability toapply the self-control skill in critical situations in everyday life. A review of the literature concerning temperature-biofeedback in the treatment of migraine headaches shows that the research from this point of view is in a rather poor state of affairs and that no definite conclusion can in fact be drawn about the degree of self-control which has been achieved and hence of the ultimate clinical value of biofeedback.This study was supported by grant no. 80/66 from the Bank of Sweden Tercentenary Foundation. 相似文献
994.
Freezing of spinach or barley chloroplasts during continuous illumination results in the trapping of a paramagnetic state or a mixture of such states characterized by a multiline EPR spectrum. Added Photosystem II electron acceptor enhances the signal intensity considerably. Treatments which abolish the ability of the chloroplasts to evolve oxygen, by extraction of the bound manganese, prevent the formation of the paramagnetic species. Restoration of Photosystem II electron transport in inhibited chloroplasts with an artificial electron donor (1,5-diphenylcarbazide) does not restore the multiline EPR spectrum. The presence of 3-(3,4-dichlorophenyl)-1, 1-dimethylurea (DCMU) results in a modified signal which may represent a second paramagnetic state. The paramagnetic forms appear to originate on the donor side in Photosystem II and are dependent on a functional oxygenevolving site and bound, intact manganese. It is suggested that magnetically interacting manganese ions in the oxygen-evolving site may be responsible for the EPR signals. This suggestion is supported by calculations. 相似文献
995.
A Inui M Okita T Inoue N Sakatani M Oya H Morioka T Ogawa N Mizuno S Baba 《Peptides》1988,9(5):1093-1100
We investigated the mechanism by which CCK-8 injected into the third cerebral ventricle (ITV administration) inhibits food intake and stimulates insulin and pancreatic polypeptide (PP) secretion in the dog. ITV administration of CCK-8 (4.08 micrograms/5 min) resulted in a significant elevation of plasma insulin and PP concentrations. This effect was abolished by truncal vagotomy and promptly inhibited by ITV administration of atropine (20 micrograms) and proglumide (10 mg). CCK-8 was less effective in increasing insulin and PP concentrations than in reducing feeding. Thus, 1.36 micrograms of ITV CCK-8 markedly reduced food intake to 14, 15, 29 and 31% of control values at 10, 30, 60 and 120 min, respectively. Atropine and naloxone (50 micrograms) had no blocking effect on CCK-8-induced satiety, whereas proglumide antagonized it. These results indicate that ITV CCK-8 effects the endocrine pancreas and food intake through atropine-sensitive and atropine-insensitive mechanisms, respectively, both of which are likely to be mediated by CNS CCK receptors. Intravenous CCK-8 also stimulated PP and insulin release, through mechanisms that were atropine-sensitive and atropine-insensitive, respectively. However, its mode of action, especially on insulin secretion, was quite different from that of ITV CCK-8. Therefore, exogenous CCK appears to act in the brain and the periphery in concert with and independently from cholinergic systems. 相似文献
996.
The changes in the levels of proline, sugar and soluble protein during leaf rolling and its relationship to osmotic adjustment
were studied in laboratory conditions. Upon irrigation of plants which have rolled leaves, many sugar crystals occurred on
the abaxial surface of the leaves in Ctenanthe setosa (Rosc.) Eichler. The sugar crystals were determined to have sucrose, glucose and fructose. The levels of reducing sugars
and proline are higher in rolled leaves while soluble protein levels in rolled leaves are lower than those of unrolled leaves.
It was found 1–3, 9–13, 16–21 and 24–28 crystals at degree of leaf rolling 23, 28, 47 and 52%, respectively. Finally, we found
a significant correlation between the crystal number and degree of leaf rolling in Ctenanthe setosa. In addition, soluble sugars are found predominant accumulating solute in the plant and are of major importance as a contributor
to osmotic adjustment during leaf rolling. 相似文献
997.
Abstract Volcanic archipelagos represent excellent areas to study colonization and speciation processes. The grasshopper genus Arminda is one of many endemic taxa of the Canary Islands. It consists of seven wingless species, most of which are single‐island endemics. We sequenced two mitochondrial (12s rRNA, ND5) and two nuclear gene fragments (28s rRNA, ITS2) to reconstruct the colonization pattern of the genus. Our results are in accordance with a stepping‐stone colonization model from east to west, corresponding to the prevailing ocean currents, but alternative hypotheses cannot be fully rejected. The populations of A. brunneri from Tenerife belong to two different lineages (east and west) consistent with the geological history of the island. It remains to be tested whether these lineages represent different species and whether further lineages exist on this island. The five clades of the four western islands (A. brunneri group) have approximately similar branch lengths. The short internodes between these lineages resulted in a poorer phylogenetic resolution. Specimens from La Palma were genetically distinct and are subsequently described as a new species, Arminda palmae sp.n. Our results suggest in situ speciation on Gran Canaria, which was accompanied by a stronger degree of morphological diversification than the inter‐island speciation processes. The aberrant species A. canariensis has formerly been assigned to a monotypic subgenus Chopardminda, which is now synonymized with Arminda syn.n. based on its phylogenetic position. Gran Canaria seems to be the only island where Arminda species occur sympatrically, although allopatric speciation seems likely due to the long history of volcanism and erosion on the island. 相似文献
998.
Elif İlkay Taşkın Kadriye Akgün‐Dar Ayşegül Kapucu Esma Osanç Hüsniye Doğruman Hakan Eraltan Engin Ulukaya 《Cell biochemistry and function》2009,27(8):542-546
Morinda citrifolia L. (Noni) is a herbal remedy with promising anti‐cancer properties. However, its effects on various cancers are to be investigated to make a firm conclusion before implementing it into the clinical practice. Therefore, we investigated the cytotoxic potential of noni on Ehrlich ascites tumor grown in female Balb‐c mice and also combined it with a potent anti‐cancer agent, doxorubicin. One group received noni only (n = 8), another one doxorubicin (n = 8), and the other one noni + doxorubicin (n = 8) for 14 days after the inoculation of cells. The control group (n = 7) received 0.9% NaCl only. We found that short and long diameters of the tumor tissues were about 40–50% smaller, compared to those in control group. This anti‐growth effect resulted from the induction of apoptosis, which was confirmed by the positive results from the Terminal Deoxynucleotidyl Transferase dUTP Nick End Labeling (TUNEL) analysis and the active caspase‐3 cells in tissues. Apoptosis also confirmed by caspase‐cleaved cytokeratin 18 elevation in serum of the treated groups. Further, the proliferation was decreased, which was immunohistochemically shown by the PCNA staining. We conclude that noni may be useful in the treatment of breast cancer either on its own or in combination with doxorubicin. Further studies are warranted to assess the dosage and safety of using noni fruit juice in conjuction with anti‐cancer drugs against breast cancer. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
999.
Özlen Güzel Alfonso Maresca Rebecca A. Hall Andrea Scozzafava Antonio Mastrolorenzo Fritz A. Mühlschlegel Claudiu T. Supuran 《Bioorganic & medicinal chemistry letters》2010,20(8):2508-2511
A series of 2-(hydrazinocarbonyl)-3-substituted-phenyl-1H-indole-5-sulfonamides and 1-({[5-(aminosulfonyl)-3-phenyl-1H-indol-2-yl]carbonyl}amino)-2,4,6 trimethylpyridinium perchlorates possessing various 2-, 3- or 4-substituted phenyl groups with methyl-, halogeno- and methoxy-functionalities, as well as the perfluorophenyl moiety, have been evaluated as inhibitors of the β-carbonic anhydrases (CAs, EC 4.2.1.1) from the pathogenic fungi Cryptococcus neoformans (Can2) and Candida albicans (CaNce103). Both enzymes were potently inhibited by these sulfonamides, KIs in the range of 4.4–118 nM against Can2, and of 5.1–128 against CaNce103, respectively. Minor structural changes in the 3-substituted phenyl moiety contribute significantly to the inhibitory activity. Some of the investigated sulfonamides showed promising selectivity ratios for inhibiting Can2 over the host, human enzymes CA I and II. 相似文献
1000.
Georgi Markov Nuri Yiğit Ercüment Çolak Maria Kocheva Milena Gospodinova 《Biologia》2014,69(1):101-106
This study aims to represent the first report on population variation of 20 non-metric skull characters in East European vole (Microtus levis) from the Balkan (populations from Northern Dobruja; Southern Dobruja; East part of the Danube Plain; North-east Trace; Sofia field; South-east Trace) and Anatolian peninsulas (populations from North-west Anatolia region and Central Anatolia region), on the basis of which to determine its epigenetic variability and to analyse their mutual geographical epigenetic relations through comparison of the epigenetic divergence among them. Estimation of epigenetic variation of the studied populations of M. levis showed similar pattern of variation, but it is mostly higher than the other rodent species with a similar range of distribution, such as Microtus arvalis, Mus musculus, Apodemus sylvaticus, Apodemus flavicollis and Clethrionomys glareolus. Each one of the studied traits manifested some polymorphism. Moreover, all the calculated epigenetic distances (MMD) were statistically insignificant (P < 0.05) and epigenetic cranial uniqueness (MU) of any studied population was not found. These results reveal lack of expressed geographic relationship of population epigenetic variability in East European vole. The revealed populations epigenetic polymorphism of M. levis gives an opportunity for more complete assessment of variability and biological diversity of this species, but further research is necessary to elucidate its population epigenetics, especially as the data obtained in recent investigations of cranial morphology of the sibling species from the group the M. arvalis (sensu lato) added new locations to the distribution map of the East European vole in Eurasia. 相似文献