genetic characteristic

遗传特征
  • 文章类型: Journal Article
    由于抗生素抗性细菌的去除无效,目前的消毒过程会带来新的环境风险,尤其是携带多重耐药质粒(MRP)的消毒残留细菌(DRB)。然而,DRB携带的MRP的特征知之甚少。在这项研究中,qPCR分析显示,消毒后废水中四种质粒的总绝对丰度降低了1.15个对数单位,与所研究的废水处理厂(WWTP)进水相比,它们的相对丰度增加了0.11个拷贝/细胞。我们从消毒后的废水中获得了三种独特的DRB携带的MRP(pWWTP-01-03),每个携带9-11个抗生素抗性基因(ARGs)。pWWTP-01包含25Kbp嵌合基因组岛内的所有11个ARGs,显示出与食源性暴发和医院的MRP的强烈重组模式。抗生物制剂-,消毒剂-,同一质粒上的重金属抗性基因强调了消毒剂和重金属在ARG共选择中的潜在作用。此外,pWWTP-02有一个粘附素类型的毒力操纵子,意味着进入环境后抗生素耐药性和致病性的风险。此外,来自DRB的一些MRP能够转移,并且可以在环境相关的抗生素压力下赋予接受者选择性优势.总的来说,这项研究提高了我们对DRB携带的MRP的理解,并强调了监测和控制废水MRP以实现环境安全的迫切需要。
    Current disinfection processes pose an emerging environmental risk due to the ineffective removal of antibiotic-resistant bacteria, especially disinfection residual bacteria (DRB) carrying multidrug-resistant plasmids (MRPs). However, the characteristics of DRB-carried MRPs are poorly understood. In this study, qPCR analysis reveals that the total absolute abundance of four plasmids in postdisinfection effluent decreases by 1.15 log units, while their relative abundance increases by 0.11 copies/cell compared to investigated wastewater treatment plant (WWTP) influent. We obtain three distinctive DRB-carried MRPs (pWWTP-01-03) from postdisinfection effluent, each carrying 9-11 antibiotic-resistant genes (ARGs). pWWTP-01 contains all 11 ARGs within an ∼25 Kbp chimeric genomic island showing strong patterns of recombination with MRPs from foodborne outbreaks and hospitals. Antibiotic-, disinfectant-, and heavy-metal-resistant genes on the same plasmid underscore the potential roles of disinfectants and heavy metals in the coselection of ARGs. Additionally, pWWTP-02 harbors an adhesin-type virulence operon, implying risks of both antibiotic resistance and pathogenicity upon entering environments. Furthermore, some MRPs from DRB are capable of transferring and could confer selective advantages to recipients under environmentally relevant antibiotic pressure. Overall, this study advances our understanding of DRB-carried MRPs and highlights the imminent need to monitor and control wastewater MRPs for environmental security.
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  • 文章类型: Journal Article
    牛副流感病毒3型(BPIV-3)是牛呼吸道疾病复合体(BRDC)的主要病原体之一。BPIV-3在中国的监测相当有限。在这项研究中,我们用PCR检测了中国的302头牛,发现阳性率为4.64%,羊群水平阳性率为13.16%。分离出6株BPIV-3C菌株,并通过电子显微镜证实,并确定了它们的滴度。通过下一代测序(NGS)对三个进行测序。系统发育分析表明,所有分离株与宁夏NX49菌株的亲缘关系最密切;基因型C菌株的遗传多样性低于基因型A和B菌株;HN,P,和N基因更适合BPIV-3的基因分型和进化分析。蛋白质变异分析表明,所有分离株在蛋白质HN的氨基酸位点都有突变,M,F,遗传重组分析为牛来源的BPIV-3的同源重组提供了证据。毒力实验表明,湖北-03菌株的致病性最高,可作为候选疫苗。这些发现为中国BPIV-3的精确控制提供了重要依据。
    Bovine parainfluenza virus type 3 (BPIV-3) is one of the major pathogens of the bovine respiratory disease complex (BRDC). BPIV-3 surveillance in China has been quite limited. In this study, we used PCR to test 302 cattle in China, and found that the positive rate was 4.64% and the herd-level positive rate was 13.16%. Six BPIV-3C strains were isolated and confirmed by electron microscopy, and their titers were determined. Three were sequenced by next-generation sequencing (NGS). Phylogenetic analyses showed that all isolates were most closely related to strain NX49 from Ningxia; the genetic diversity of genotype C strains was lower than strains of genotypes A and B; the HN, P, and N genes were more suitable for genotyping and evolutionary analyses of BPIV-3. Protein variation analyses showed that all isolates had mutations at amino acid sites in the proteins HN, M, F, and L. Genetic recombination analyses provided evidence for homologous recombination of BPIV-3 of bovine origin. The virulence experiment indicated that strain Hubei-03 had the highest pathogenicity and could be used as a vaccine candidate. These findings apply an important basis for the precise control of BPIV-3 in China.
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  • 文章类型: Journal Article
    牦牛由于其地理和生态环境,已经进化出几种品种或遗传资源,研究品种间体型的遗传构建是育种的关键。这里,对31个牦牛品种和遗传资源的5个体型性状进行了全基因组关联研究(GWAS).根据栖息地对个体进行聚类的信息用于压缩混合线性模型(CMLM)中的亲属关系分组。我们将这种方法命名为pCMLM方法。共获得3,584,464个高质量的单核苷酸多态性(SNPs),pCMLM发现六个标记与身高显着相关。四个候选基因,包括FXYD6、SOHLH2、ADGRB2和OSBPL6。我们的结果表明,当CMLM无法识别最佳聚类组时,pCMLM可以基于人口信息提供足够的关联结果。此外,本研究为牦牛品种体型数量性状的基因定位提供了基础信息。
    Yaks have evolved several breeds or genetic resources owing to their geographical and ecological environment, and investigating the genetic construction of body size among breeds is key for breeding. Here, a genome-wide association study (GWAS) was performed for five body size traits in 31 yak breeds and genetic resources. The information from clustering individuals according to their habitats was used for kinship grouping in the compressed mixed linear model (CMLM). We named this approach the pCMLM method. A total of 3,584,464 high-quality single nucleotide polymorphisms (SNPs) were obtained, and six markers were found to be significantly associated with height by pCMLM. Four candidate genes, including FXYD6, SOHLH2, ADGRB2, and OSBPL6, were identified. Our results show that when CMLM cannot identify optimal clustering groups, pCMLM can provide sufficient associated results based on population information. Moreover, this study provides basic information on the gene localization of quantitative traits of body size among yak breeds.
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  • 文章类型: Journal Article
    背景:甘草具有多种作用,包括补脾补气,清除热量和有毒物质,祛痰,缓解咳嗽和疼痛,协调其他药物的效果。它广泛用于制药和食品工业。
    目的:本综述对甘草属植物的鉴定进行了系统整理。具有药用价值的物种及其分布。形态和遗传特征,分布,中国的储备数量,适宜的环境,综述了重要药用物种适宜生境的面积。综述了自然环境和栽培管理(水和养分)对甘草生长和品质的影响。目的是使人们对G.Linn的药用植物资源状况有一个系统的了解。,了解影响其质量的自然和人为因素,从而为今后重要药用甘草资源的收集和人类对其质量的控制提供帮助。
    方法:我们对主要文献进行了广泛的搜索,硕士和博士论文,和许多国家使用PubMed的药典,Geenmedical,CNKI,WebofScience,SCI-hub和其他数据库。搜索中使用的关键词包括“甘草的分类,\"\"药用甘草,甘草的“\”分布,\"和\"甘草适宜环境\"由我们的研究小组进行的形态学和遗传特征的研究结果,自然分布,综述了人工调控对甘草生长和品质的影响。
    结果:大约有29种G.Linn。全世界,包括15种具有药用价值。这些物种分布在除南极洲以外的所有大陆上,分布在41个国家。印度药典中只有一种甘草,在美国和日本药典中记录了两个物种,在大多数国家药典中记录了三种:G.glabraLinn。,G.uralensisFisch。还有G.InflataBatalin.这三种药用甘草主要分布在欧亚大陆,尤其是中亚。这三种药用甘草之间的主要形态差异在叶子上,花序,豆荚,和种子,它们可以通过ITS和psbA-trnH序列来区分。2010年,中国野生甘草的储量每年减少至104万(t)。中国乌拉尔费希的种植面积目前约为26,900hm2。土壤条件对乌拉尔的产量和质量有很大影响,特别是水和营养。适当的灌溉和施肥措施可以提高乌拉尔草的质量。
    结论:G.林恩总结了物种及其自然分布。形态学,遗传特征,适宜的环境,描述了在主要国家收集的三种药用甘草的适宜栖息地面积。确定了影响其生长和药用品质的主要环境条件和栽培措施。本文对G.Linn进行了全面综述。药用植物资源,以提高这些资源的未来利用。
    BACKGROUND: Glycyrrizae Radix et Rhizoma has various effects, including tonifying the spleen and qi, clearing heat and toxic substances, eliminating phlegm, relieving cough and pain, and harmonizing the effects of other medicines. It is widely used in the pharmaceutical and food industries.
    OBJECTIVE: This review systematically collates the identification of Glycyrrhiza Linn. species with medicinal value and their distributions. The morphological and genetic characteristics, distribution, quantity of reserves in China, suitable environment, and area of suitable habitat of important medicinal species were reviewed. The effects of the natural environment and cultivation management (water and nutrients) on the growth and quality of licorice were reviewed. The aim is to make people have a systematic understanding of the status of medicinal plant resources of the G. Linn., and understand the natural and human factors that affect its quality, so as to provide help for the collection of resources of the important medicinal licorice and the human control of its quality in the future.
    METHODS: We conducted extensive searches of the primary literature, master\'s and doctoral theses, and pharmacopeias of many countries using PubMed, Geenmedical, CNKI, Web of Science, SCI-hub and other databases. The keywords used in searches included \"classification of Glycyrrhiza,\" \"medicinal Glycyrrhiza,\" \"distribution of Glycyrrhiza,\" and \"suitable environment for Glycyrrhiza\" The results of research conducted by our research group on the morphological and genetic characteristics, natural distribution, and effects of artificial regulation on the growth and quality of licorice were summarized.
    RESULTS: There are approximately 29 species of G. Linn. worldwide, including 15 species with medicinal value. These species occur on all continents except Antarctica across 41 countries. Only one licorice is recorded in Indian pharmacopoia,two species are recorded in US and Japanese pharmacopoeias,and three species are recorded in most national pharmacopoeias: G. glabra Linn., G. uralensis Fisch. and G. inflata Batalin. These three medicinal licorice species are mainly distributed in Eurasia, especially Central Asia. The main morphological differences between these three medicinal licorice species are in the leaves, inflorescences, pods, and seeds, and they can be distinguished by ITS and psbA-trnH sequences. The reserves of wild licorice in China have decreased annually to 1.04 million(t) in 2010. The cultivation area of G. uralensis Fisch in China is currently approximately 26,900 hm2. Soil conditions have a substantial effect on the yield and quality of G. uralensis Fisch, especially water and nutrients. Appropriate irrigation and fertilization measures can enhance the quality of G. uralensis Fisch.
    CONCLUSIONS: G. Linn. species and their natural distributions were summarized. The morphology, genetic characteristics, suitable environment, and area of suitable habitat of three medicinal licorice species collected in major countries were described. The main environmental conditions and cultivation measures affecting their growth and medicinal quality were determined. This article provides a comprehensive review on G. Linn. medicinal plant resources to enhance the future use of these resources.
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  • 文章类型: Journal Article
    研究的目的是更好地了解中国苗族的遗传特征。在这里,在来自中国云南苗族(YM)组的210名无关健康个体中,研究了57个常染色体插入缺失(InDel)基因座的遗传特征和法医学应用价值。同时,在YM组和26个参考人群中比较了这些InDel的遗传差异。法医统计分析结果表明,中国YM组中所有57个常染色体InDel均符合Hardy-Weinberg和成对基因座的连锁平衡。此外,YM组的综合判别概率和排除概率分别为0.999999999999999999999999801和0.99999928,这表明包括57个常染色体InDels的多重扩增适合中国YM组的法医个体鉴定和亲子鉴定。此外,等位基因频率分布差异分析的结果,主成分分析,系统发育树重建,和中国YM群体与26个参考种群之间的遗传结构分析表明,YM群体与东亚种群之间的遗传相似性大于YM群体与其他地理种群之间的遗传相似性。这种57常染色体InDels系统也可以有效区分东亚,欧洲,和非洲人口。
    The aim of the study was to better understand the genetic characteristics of the Miao group in China. Herein, genetic characteristics and forensic application values of 57 autosomal insertion-deletion (InDel) loci were investigated in 210 unrelated healthy individuals from the Chinese Yunnan Miao (YM) group. Meanwhile, the genetic differences in these InDels were compared among the YM group and 26 reference populations. The results of forensic statistical analyses showed that all 57 autosomal InDels were in accordance with the Hardy-Weinberg and linkage equilibria of pairwise loci in the Chinese YM group. Moreover, the combined probability of discrimination and probability of exclusion in the YM group were 0.9999999999999999999999801 and 0.999928, respectively, which indicated that the multiplex amplification including 57 autosomal InDels was suitable for forensic individual identification and paternity testing in the Chinese YM group. In addition, the results of allelic frequency distribution differential analyses, principal component analyses, phylogenetic tree reconstruction, and genetic structure analyses between the Chinese YM group and 26 reference populations revealed that the genetic similarities between the YM group and East Asian populations were more than that between the YM group and other geographical populations. This 57 autosomal InDels system can also effectively distinguish East Asian, European, and African populations.
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  • 文章类型: Journal Article
    鼠Kobuvirus(MuKV)是Kobuvirus属的一种新型小核糖核酸病毒,并于2011年在美国的鼠类啮齿动物粪便中首次发现。关于MuKV的传输路由的信息有限。因此,我们进行了一项研究,以调查粪便中的病毒检测率,血清,喉咙,和鼠啮齿动物的肺组织样本.
    总共413个粪便样本,385个肺样本,269个咽喉拭子样本,并从413只小鼠啮齿动物(Rattusnorvegicus,Rattustanezumi,和Rattusrattus)在深圳市区捕获。通过RT-PCR检测科布病毒。只有粪便样本呈阳性,褐家鼠的患病率为34.9%,白家鼠的患病率为29.4%。基于部分3D和完整VP1序列区域的系统发育分析表明,获得的所有MuKV序列均属于AichirvirusA,在基因上与中国报道的其他MuKV密切相关,匈牙利,和美国。获得了28个全长MuKV序列。从两个物种(SZ59和SZ171)中随机选择的两个序列的系统发育分析表明,它们彼此之间具有非常高的核苷酸和氨基酸同一性(94.0和99.3%,分别),与人类Kobuvirus的比较显示氨基酸同一性值为〜80%。此外,污水衍生序列与本研究中确定的大鼠衍生序列具有高度相似性,相应的核苷酸和氨基酸同一性值从86.5和90.7%到87.2和91.1%。
    本研究的结果提供了鼠科布病毒通过粪-口途径传播的证据。
    Murine Kobuvirus (MuKV) is a novel picornavirus of the genus Kobuvirus, and was first identified in the feces of murine rodents in the USA in 2011. There is limited information on the transmission route of MuKV. Thus, we conducted a study to investigate virus detection rates in fecal, serum, throat, and lung tissue samples from murine rodents.
    A total of 413 fecal samples, 385 lung samples, 269 throat swab samples, and 183 serum samples were collected from 413 murine rodents (Rattus norvegicus, Rattus tanezumi, and Rattus rattus) captured in urban Shenzhen. Kobuviruses were detected via RT-PCR. Only fecal samples were positive, with prevalence rates of 34.9% in Rattus norvegicus and 29.4% in Rattus tanezumi. Phylogenetic analysis based on partial 3D and complete VP1 sequence regions indicated that all of the MuKV sequences obtained belonged to Aichivirus A, and were genetically closely related to other MuKVs reported in China, Hungary, and the USA. Twenty-eight full-length MuKV sequences were acquired. Phylogenetic analysis of two sequences randomly selected from the two species (SZ59 and SZ171) indicated that they shared very high nucleotide and amino acid identity with one another (94.0 and 99.3%, respectively), and comparison with human Kobuvirus revealed amino acid identity values of ~80%. Additionally, a sewage-derived sequence shared high similarity with the rat-derived sequences identified in this study, with respective nucleotide and amino acid identity values from 86.5 and 90.7% to 87.2 and 91.1%.
    The results of the current study provide evidence that murine Kobuvirus is transmitted via the fecal-oral route.
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  • 文章类型: Journal Article
    生殖器沙眼衣原体(CT)是性传播感染的最常见因子之一,可引起严重疾病。本研究旨在分析广州地区女性生殖器CT感染的遗传和临床特点。中国。
    从2020年9月到2021年8月,共有8955名女性患者参加了这项研究。通过实时PCR检测生殖器CT的存在,随机选择273例阳性样本进行进一步的遗传和临床特征分析。
    生殖器CT感染阳性率为7.5%(670/8955),在21-30岁的女性中比例最高。共鉴定出8种基因型:DH,J,K,和重组基因型Ba/D主要基因型为J(n=78,28.6%),其次是E(n=63,23.1%),F(n=48,17.6%),D(n=38,13.9%)。阴道分泌物异常(n=165,61.8%),宫颈柱状上皮异位(n=124,46.4%),阴道瘙痒(n=77,28.8%),下腹疼痛(n=61,22.8%)是主要症状。此外,与其他基因型相比,基因型G感染表现出明显更高的阴道分泌物异常率(P=0.03),基因型D感染表现出更高的白细胞计数(P=0.01)。系统发育分析显示,共有20种变异,具有25个突变位置,在我们的研究中首次发现了四名患者的H2变异。
    基因型J,E,F,和D是广州生殖器CT的主要基因型,表现为异常的阴道分泌物,宫颈柱状上皮异位,阴道瘙痒,和下腹部疼痛。本研究为未来的综合干预措施提供了指导,以减轻生殖器CT感染的负担并加快疫苗的开发。
    Genital Chlamydia trachomatis (CT) is one of the most common agents of sexually transmitted infections and can cause severe disorders. This study aimed to analyse the genetic and clinical characteristics of genital CT infection among women in Guangzhou, China.
    From September 2020 to August 2021, a total of 8955 female patients were enrolled in this study. The presence of genital CT was detected by real-time PCR, and 273 positive samples were randomly selected for further genetic and clinical characteristics analysis.
    The positive rate of genital CT infection was 7.5% (670/8955), with the highest rate in women aged 21-30 years. A total of 8 genotypes were identified: DH, J, K, and recombinant genotype Ba/D. The predominant genotype was J (n = 78, 28.6%), followed by E (n = 63, 23.1%), F (n = 48, 17.6%), and D (n = 38, 13.9%). Abnormal vaginal discharge (n = 165, 61.8%), cervical columnar epithelial ectopy (n = 124, 46.4%), vaginal itching (n = 77, 28.8%), and lower abdominal pain (n = 61, 22.8%) were the predominant symptoms. Additionally, genotype G infection exhibited a significantly higher rate of abnormal vaginal discharge (P = 0.03) and genotype D infection exhibited a higher white blood cell count (P = 0.01) than the other genotypes. Phylogenetic analysis revealed a total of 20 variants with 25 mutation positions and the H2 variant in four patients was first discovered in our study.
    Genotypes J, E, F, and D were the major genotypes of genital CT in Guangzhou, and they manifested as abnormal vaginal discharge, cervical columnar epithelial ectopy, vaginal itching, and lower abdominal pain. The present study provides guidance for future integrated interventions to reduce the burden of genital CT infection and accelerate the development of vaccines.
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  • 文章类型: Journal Article
    Distant hybridization can combine whole genomes from parent species and result in changes in the phenotypes and genotypes in hybrids. The characteristics of many hybrid fishes with even number of chromosomes have been reported, but the hybrids with odd number chromosomes are rarely reported. Blunt snout bream (Megalobrama amblycephala, BSB, 2n = 48) and rare gudgeon (Gobiocypris rarus, RG, 2n = 50) belong to two different subfamilies and have quite different biological characteristics. In this study, we obtain the hybrids (BR) derived from the inter-subfamily hybridization of female BSB and male RG. We investigate the fertilization rate, hatching rate, morphological traits, chromosomal numbers, DNA content, growth rates, and 5S rDNA in the BR. The results show that the BR is an allodiploid fish with 49 chromosomes, and all the measurable traits are significantly different (p < 0.05) among BR, BSB, and BR. Interestingly, the upper part of the BR body color is similar to BSB (gray), the lower part of the BR body color is similar to RG (light yellow), and the BR inherits a unique light yellow wide longitudinal band from the RG. Furthermore, the BR has a fast growth rate compared with RG. The 5S rDNA of the BR inherits the specific bands of its parental 5S rDNA respectively and has some mutations, which show obvious recombination, heredity, and variability in BR. This study will be of great significance in fish genetic breeding.
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  • 文章类型: Journal Article
    BACKGROUND: Several members of genus Babesia are important pathogens causing babesiosis in dogs. In China, at least five Babesia species have been described in dogs or ticks. This study sought to determine the prevalence and molecular characteristics of various Babesia spp. in dogs in cities in Shaanxi Province in China, including Xi\'an and Hanzhong.
    METHODS: A total of 371 blood samples were collected from pet dogs presenting to veterinary clinics in the cities of Xi\'an and Hanzhong in Shaanxi, China. Babesia spp. DNA was detected via amplification of partial 18S rRNA genes by semi-nested PCR. Almost full-length 18S rRNA, ITS, partial TRAP and complete cytb genes were recovered for analysis of the genetic characteristics and relationships with known isolates.
    RESULTS: A single species, Babesia gibsoni, was identified in dogs in Xi\'an and Hanzhong. Consistently, B. gibsoni was also detected in 14 ticks collected from positive dogs. Sequence similarities and phylogenetic analysis suggested that the isolates identified herein showed a closer genetic relationship with isolates from East Asian countries rather than India, Bangladesh, or the USA. Sequence analysis based on tandem repeat analysis of the TRAP gene further revealed that specific haplotypes were circulating in both Xi\'an and Hanzhong, with no specific regionality. In addition, 10.9% of all isolates with atovaquone (ATV)-resistance were identified because of M121I mutation in the deduced cytb protein.
    CONCLUSIONS: This study revealed a high prevalence rate of Babesia infection. Babesia gibsoni was the only Babesia species identified in cases of canine babesiosis in the cities of Xi\'an and Hanzhong cities in Shaanxi, China. In addition, the TRAP gene presented high genetic diversity across isolates. Such information is useful for elucidating the epidemiological characteristics of canine babesiosis, as well as the overall genetic diversity of Babesia spp. circulating in dog populations in Shaanxi Province.
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  • 文章类型: Journal Article
    Murine kobuviruses (MuKV) are newly recognized picornaviruses first detected in murine rodents in the USA in 2011. Little information on MuKV epidemiology in murine rodents is available. Therefore, we conducted a survey of the prevalence and genomic characteristics of rat kobuvirus in Guangdong, China.
    Fecal samples from 223 rats (Rattus norvegicus) were collected from Guangdong and kobuviruses were detected in 12.6% (28) of samples. Phylogenetic analysis based on partial 3D and complete VP1 sequence regions showed that rat kobuvirus obtained in this study were genetically closely related to those of rat/mouse kobuvirus reported in other geographical areas. Two near full-length rat kobuvirus genomes (MM33, GZ85) were acquired and phylogenetic analysis of these revealed that they shared very high nucleotide/amino acids identity with one another (95.4%/99.4%) and a sewage-derived sequence (86.9%/93.5% and 87.5%/93.7%, respectively). Comparison with original Aichivirus A strains, such human kobuvirus, revealed amino acid identity values of approximately 80%.
    Our findings indicate that rat kobuvirus have distinctive genetic characteristics from other Aichivirus A viruses. Additionally, rat kobuvirus may spread via sewage.
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