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991.
Liu JH  Okazaki K  Mweene A  Shi WM  Wu QM  Su JL  Zhang GZ  Bai GR  Kida H 《Virus genes》2004,29(3):329-334
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   
992.
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   
993.

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   
994.
995.

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   
996.
Background: The high speed and processivity of replicative DNA polymerases reside in a processivity factor which has been shown to be a ring-shaped protein. This protein (‘sliding clamp’) encircles DNA and tethers the catalytic unit to the template. Although in eukaryotic, prokaryotic and bacteriophage-T4 systems, the processivity factors are ring-shaped, they assume different oligomeric states. The Escherichia coli clamp (the β subunit) is active as a dimer while the eukaryotic and T4 phage clamps (PCNA and gp45, respectively) are active as trimers. The clamp can not assemble itself on DNA. Instead, a protein complex known as a clamp loader utilizes ATP to assemble the ring around the primer-template. This study compares properties of the human PCNA clamp with those of E. coli and T4 phage. Results: The PCNA ring is a stable trimer down to a concentration below 100 nm (Kd ≈ 21 nm ). On DNA, the PCNA clamp slides freely and dissociates from DNA slowly (t1/2 ≈ 24 min). β is more stable in solution (Kd < 60 pm ) and on DNA (t1/2 ≈ 1 h) than PCNA which may be explained by its simpler oligomeric state. The T4 gp45 clamp is a much less stable trimer than PCNA (Kd ≈ 250 nm ) and requires association with the polymerase to stabilize it on DNA as observed previously. The consequence of this cooperation between clamp and polymerase is that upon finishing a template and dissociation of the polymerase from DNA, the gp45 clamp spontaneously dissociates from DNA without assistance. However, the greater stability of the PCNA and β clamps on DNA necessitates an active process for their removal. The clamp loaders (RF-C and γ complex) were also capable of unloading their respective clamps from DNA in the presence of ATP. Conclusions: The stability of the different clamps in solution correlates with their stability on DNA. Thus, the low stability of the T4 clamp explains the inability to isolate gp45 on DNA. The stability of the PCNA and β clamps predicts they will require an unloading factor to recycle them on and off DNA during replication. The clamp loaders of PCNA and β double as clamp unloaders presumably for the purpose of clamp recycling.  相似文献   
997.

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   
998.
目的 为从基因水平抑制呼吸道合胞病毒(respiratory syncytial virus,RSV)的复制,针对RSV的M2-2基因构建小发卡结构状RNA(short hairpin RNA,shRNA)重组质粒,在细胞水平观察shRNA对RSV复制的影响。方法 将成功构建的针对RSV M2-2基因的重组质粒pshRNA8260转染HEp-2细胞,利用光镜观察pshRNA8260对RSV致HEp-2细胞病变效应(cytopathogenic effect,CPE)的影响并计算CPE抑制率,空斑形成实验检测RSV滴度变化。结果 成功构建了针对人RSV M2-2基因mRNA的pshRNA8260重组质粒,研究发现pshRNA8260能明显改善RSV所致的病变效应,降低RSV在细胞内复制的病毒滴度。结论 针对RSV M2-2基因的pshRNA82(g)重组质粒具有明显的特异性抗RSV效应的作用。  相似文献   
999.
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   
1000.
目的 分析2015—2020年四川省手足口病流行病学及病原学特征,为手足口病的防控提供科学依据。 方法 利用描述流行病学方法对2015—2020年四川省手足口病监测资料进行统计分析。 结果 2015—2020年四川省累计报告手足口病520 147例,重症1 759例,死亡38例,2015—2020年四川省手足口病发病率呈波动状,年均发病率为104.82/10万,2015—2017和2019年呈现明显的双峰(4—7月和10—12月),2018、2020年呈单峰,发病高峰分别在7—11月和10—12月;年龄以 5 岁及以下儿童为主,男女性别比为1.38∶1;发病率居前五位的地区是成都市(221.25/10万)、眉山市(145.51/10万)、德阳市(115.52/10万)、雅安市(108.02/10万)和遂宁市(100.56/10);共报告实验室确诊病例44 410例,其中其他肠道病毒、CoxA16、EV71分别占65.53%、22.35%、12.12% 。 结论 2015—2020年四川省手足口病发病水平呈上升趋势,防控压力逐渐加大。四川省手足口病发病以5岁以下儿童为主,成都及周边,川东北发病率较高,优势病原分型构成发生变化,其他肠道病毒比重逐渐提高,病原学监测工作需要调整。  相似文献   
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