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911.
Genetic Conservation of Hemagglutinin Gene of H9 Influenza Virus in Chicken Population in Mainland China 总被引:1,自引:0,他引:1
The hemagglutinin (HA) genes of 12 H9N2 influenza virus strains isolated from chickens in Mainland China during the period 1995–2002 were genetically analyzed. All the isolates possessed the same amino acid motif -R-S-S-R/G-L- at the cleavage site of HA. Except for the conserved amino acids, as is the case in the other avian influenza viruses, located in the receptor binding site, all of the 12 isolates possessed N at amino acid position 183; A, T, or V at position 190; K at position 137, whereas the representative strains of the other lineage (except Dk/HK/Y280/97-like lineage) virus of H9N2 viruses had H, E, and R at these positions respectively. These could be considered as the partial molecular markers of the H9 viruses isolated from chickens in Mainland China. Phylogenetic analyses showed HA genes of these isolates belonged to that of A/duck/Hong Kong/Y280/97-like virus lineage. No A/quail/Hong Kong/Gl/97-like virus was found in chicken, population since the outbreak of H9N2 influenza in Mainland China in 1992. The available evidence indicates that HA genes of H9 influenza virus circulating in Mainland China during the past years were well conserved. 相似文献
912.
Maeno N Kusunoki K Kitajima T Iwata N Ono Y Hashimoto S Imai M Li L Kayukawa Y Ohta T Ozaki N 《Journal of affective disorders》2005,85(3):267-273
BACKGROUND: Although there have been numerous reports in personality of mood disorders, there have been few reports in regard with personality of winter seasonal affective disorder (SAD). Furthermore, no reports have been published concerning summer SAD personality characteristics. Thus, this study was conducted to assess the personality of winter and summer SAD using Tri-dimensional Personality Questionnaire (TPQ) that have been used in a variety of mental disorders. METHODS: A total of 6135 Japanese were evaluated with TPQ, the Seasonal Pattern Assessment Questionnaire (SPAQ) and the Self-rating Depression Scale (SDS). Winter, summer and non-SAD groups were classified by SPAQ. We compared the difference of personality trait among these three groups in consideration of gender, age and SDS score influence. RESULTS: Winter SAD demonstrated higher "Novelty Seeking" and "Harm Avoidance"; summer SAD showed higher "Harm Avoidance" than the non-SAD group. "Harm Avoidance" in both SAD groups was re-analyzed using SDS score as a covariate, and "Novelty Seeking" in winter SAD using age as a covariate. As a result, the significance of high "Novelty Seeking" and high "Harm Avoidance" in winter SAD was excluded. However, "Harm Avoidance" remained the significant difference between summer and non-SAD. LIMITATION: SAD was diagnosed only by SPAQ and not by interview. The state-dependency of "Harm Avoidance" was not confirmed in identical patients over lapse of time. CONCLUSION: Patients with winter SAD have high "Harm Avoidance" dependent on the depressive state that is in accordance with non-seasonal depression. Patients with summer SAD have high "Harm Avoidance" possibly independent from the depressive state. 相似文献
913.
Comparison of various bone marrow fractions in the ability to participate in vascular remodeling after mechanical injury 总被引:2,自引:0,他引:2
Sahara M Sata M Matsuzaki Y Tanaka K Morita T Hirata Y Okano H Nagai R 《Stem cells (Dayton, Ohio)》2005,23(7):874-878
In contrast to conventional assumption, recent reports propose the possibility that hematopoietic stem cells (HSCs) may have broader potential to differentiate into various cell types. Here, we tested the pluripotency of HSCs by comparing vascular lesions induced by mechanical injury after bone marrow reconstitution with total bone marrow (TBM) cells, c-Kit+ Sca-1+ Lin- (KSL) cells, or a single HSC cell (Tip-SP CD34-KSL cell, CD34- c-Kit+ Sca-1+ Lin- cell with the strongest dye-efflux activity) harboring green fluorescent protein (GFP). The lesions contained a significant number of GFP-positive cells in the TBM and KSL groups, whereas GFP-positive cells were rarely detected in the HSC group. These results suggest that transdifferentiation of a highly purified HSC seems to be a rare event, if it occurs at all, whereas bone marrow cells including the KSL fraction can give rise to vascular cells that substantially contribute to repair or lesion formation after mechanical injury. 相似文献
914.
Charles R. Bursey Stephen R. Goldberg 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2007,52(4):368-370
Aplectana krausi sp. nov. (Ascaridida, Cosmocercidae) from the intestines of Platymantis boulengeri (Anura, Ceratobatrachidae) is described and illustrated. Aplectana krausi represents the 42nd species assigned to the genus, the 4th species reported from the Australo-Papuan region. It is easily
separated from the three species previously reported from the region by the distribution pattern of male caudal papillae:
A. macintoshii and A. novaezelandiae have irregular patterns; A. zweifeli and A. krausi have defined patterns. Aplectana zweifeli has 8–10 precloacal, no adcloacal, and 9 postcloacal pairs of papillae, there is a single median papillae just anterior to
the cloaca; A. krausi has 5 precloacal, 1 adcloacal, and 5 postcloacal pairs of papillae, a median papillae is absent. 相似文献
915.
Francesca Fernandez Robert P Curtain Natalie J Colson Micky Ovcaric John MacMillan Lyn R Griffiths 《BMC medical genetics》2007,8(1):57
Background
Migraine with aura (MA) is a subtype of typical migraine. Migraine with aura (MA) also encompasses a rare severe subtype Familial Hemiplegic Migraine (FHM) with several known genetic loci. The type 2 FHM (FHM-2) susceptibility locus maps to chromosome 1q23 and mutations in the ATP1A2 gene at this site have recently been implicated. We have previously provided evidence of linkage of typical migraine (predominantly MA) to microsatellite markers on chromosome 1, in the 1q31 and 1q23 regions. In this study, we have undertaken a large genomic investigation involving candidate genes that lie within the chromosome 1q23 and 1q31 regions using an association analysis approach. 相似文献916.
917.
Francesca Fernandez Teresa Esposito Rod A Lea Natalie J Colson Alfredo Ciccodicola Fernando Gianfrancesco Lyn R Griffiths 《BMC medical genetics》2008,9(1):109
Background
Migraine is a neurological disorder characterized by recurrent attacks of severe headache, affecting around 12% of Caucasian populations. It is well known that migraine has a strong genetic component, although the number and type of genes involved is still unclear. Prior linkage studies have reported mapping of a migraine gene to chromosome Xq 24–28, a region containing a cluster of genes for GABA A receptors (GABRE, GABRA3, GABRQ), which are potential candidate genes for migraine. The GABA neurotransmitter has been implicated in migraine pathophysiology previously; however its exact role has not yet been established, although GABA receptors agonists have been the target of therapeutic developments. The aim of the present research is to investigate the role of the potential candidate genes reported on chromosome Xq 24–28 region in migraine susceptibility. In this study, we have focused on the subunit GABA A receptors type ε (GABRE) and type θ (GABRQ) genes and their involvement in migraine. 相似文献918.
A new pseudo-peptide of Arg-Gly-Asp (RGD) with inhibitory effect on tumor metastasis and enzymatic degradation of extracellular matrix 总被引:2,自引:0,他引:2
Hideki Fujii Naoyuki Nishikawa Hiroyuki Komazawa Makoto Suzuki Masayoshi Kojima Isamu Itoh Aya Obata Koichi Ayukawa Ichiro Azuma Ikuo Saiki 《Clinical & experimental metastasis》1998,16(1):94-104
A series of pseudo-peptide analogs of the Arg-Gly-Asp (RGD) sequence of fibronectin have been synthe-sized, and their anti-metastatic effects in mice and inhibitory effects on tumor cell invasion in vitro have been examined. The partially modified retro pseudo-peptide of RGD, Rrev-COCH2CO-D (FC-63), was more effective in inhibiting tumor metastasis than the original RGDS peptide. Replacement of the malonyl moiety of FC-63 with a carboxyethylene linkage (Rrev-COCH2CH2-D, FC-303 ) achieved more potent inhibition of lung metastasis of melanoma cells than FC-63. Among the analogs, FC-336, a p-xylylendiamine derivative having two FC-303 moieties, showed the most potent inhibitory effect on experimental lung metastasis produced by i.v. co-injection with B16-BL6 melanoma or colon 26 M3.1 cells in a dose-dependent manner. Multiple administrations of FC-336 after tumor inoculation also showed efficient therapeutic potency against spontaneous lung metastasis of B16-BL6 melanoma in mice. Furthermore, FC-336 effectively inhibited the invasion, migration and adhesion of tumor cells in vitro, but its inhibitory effects were not more than those of RGDS peptide. Zymography analysis revealed that FC-336 inhibited the degradation of gelatin substrate by matrix metalloproteinases (MMPs) produced by tumor cells, while the RGDS peptide did not affect the enzymatic degradation. These findings indicate that the pseudo-peptides of the RGD sequence, possessing the inhibitory property of the degradation by MMPs differently from original RGD-containing peptides, may be advantageous and useful in preventing tumor metastasis. © Rapid Science 1998 相似文献
919.
James F Jones Elizabeth M Maloney Roumiana S Boneva Ann-Britt Jones William C Reeves 《BMC complementary and alternative medicine》2007,7(1):12
Background
Chronic fatiguing illnesses, including chronic fatigue syndrome (CFS), pose a diagnostic and therapeutic challenge. Previous clinical reports addressed the utilization of health care provided to patients with CFS by a variety of practitioners with other than allopathic training, but did not examine the spectrum of complementary and alternative medicine (CAM) therapies used. This study was designed to measure CAM therapy use by persons with fatiguing illnesses in the United States population. 相似文献920.
Peter Bright-Asare Stephen J. Sontag Ronald J. Gould Douglas L. Brand Walter M Roufail 《Digestive diseases and sciences》1986,31(2):63S-67S
This study was undertaken to evaluate the efficacy of misoprostol taken twice daily for the healing of duodenal ulcer. Three hundred thirty patients with endoscopically proven duodenal ulcer participated in a multicenter, double-blind, controlled trial comparing placebo with misoprostol 200 μg and 400 μg twice daily for up to four weeks. Patient characteristics were similar in all three treatment groups. Ulcers were between 0.3 cm and 2.0 cm in length. Healing was determined by endoscopy at two weeks; if ulcers were not healed, endoscopy was repeated at four weeks. All patients were given Al(OH)3 antacid (up to 54 meq a day) to be used as needed for pain. Healing rates at four weeks for a total of 280 evaluable patients in the three treatment groups were as follows: misoprostol 400 μg bid, 65.4%; misoprostol 200 μg bid, 52.9%; and placebo, 42.2%. Misoprostol 400 μg bid was superior to placebo (P=0.002) in healing ulcers. However, the healing rate for misoprostol 200 μg bid did not differ significantly from placebo. The percentage of nonsmokers who healed at four weeks was higher than that of smokers in both misoprostoltreatment groups, although the difference was not analyzed for statistical significance. There were no differences in antacid consumption or pain relief among the three experimental groups during the study. Diarrhea was the most common side effect but was mild and self-limiting, occurring in 8.9%, 5.9%, and 1.8% of the misoprostol 400 μg, 200 μg, and placebo groups, respectively. These results indicate that misoprostol 400 μg, 200 μg, and for four weeks is effective and safe for the treatment of duodenal ulcers. 相似文献