戻る
「早戻しボタン」を押すと検索画面に戻ります。 [閉じる]

コーパス検索結果 (1語後でソート)

通し番号をクリックするとPubMedの該当ページを表示します
1 hemical communication (e.g., desaturases and odorant receptors).
2 teractions among neurons expressing the same odorant receptor.
3 each neuron normally expresses only a single odorant receptor.
4 ionary conservation of an important class of odorant receptor.
5  (ORNs), which in turn depends ultimately on odorant receptors.
6  of the olfactory system, including OBPs and odorant receptors.
7 might limit rather than facilitate access to odorant receptors.
8 eptors is a previously unrecognized class of odorant receptors.
9  and functional expression of representative odorant receptors.
10 in high throughput de-orphaning of mammalian odorant receptors.
11 hen compared to other chemodetectors such as odorant receptors.
12 ive (GC-D+) neurons are not known to express odorant receptors.
13 nt is detected by a combination of different odorant receptors.
14 ggests a chemosensory function distinct from odorant receptors.
15 omplexity of odorant encoding in the bed bug odorant receptors.
16 ffective in eliciting responses from bed bug odorant receptors.
17 ophobic odorants through an aqueous lymph to odorant receptors.
18                        OSNs expressing mouse odorant receptor 23 (MOR23) are relatively broadly tuned
19                             In vitro, ECB(Z) odorant receptor 3 (OR3), a sex pheromone receptor expre
20 able expansions of gustatory (116 genes) and odorant receptors (367 genes), an abundance of cytochrom
21 the expression and ligand-sensitivity of the odorant receptor AaegOr4, which we found recognizes a co
22 uantitative relationship between patterns of odorant receptor activation, the resulting internal repr
23 d model that captures the main mechanisms of odorant receptor activation.
24 s much of the conventional Anopheles gambiae odorant receptor (AgOR) repertoire was carried out in Xe
25 ctionally characterize the Anopheles gambiae odorant receptor (AgOr) repertoire.
26  have identified a subset of the An. gambiae odorant receptors (AgOrs) that are localized to discrete
27 hereas the other ORNs express characteristic odorant receptors (AgORs) that are responsible for their
28 nsory gene transcripts, although a subset of odorant receptors (AgOrs) was modestly enhanced in post-
29  functional differences at over 30% of their odorant receptor alleles.
30 the first step towards using purified insect odorant receptors alone in biosensors to enable the deve
31 dition of an N-terminal rhodopsin tag to the odorant receptors, along with the same set of accessory
32 determine how often genetic polymorphisms in odorant receptors alter receptor function.
33 s little effect on the ligand specificity of odorant receptors, although the amount of receptor expre
34  the ORNs that normally express a particular odorant receptor and find that PNs postsynaptic to the s
35      This modulation depends on the specific odorant receptor and the concentration and identity of t
36 that express a large repertoire of canonical odorant receptors and a much smaller repertoire of trace
37 d receptors: a large repertoire of canonical odorant receptors and a much smaller set of trace amine-
38 ype, for example, differential expression of odorant receptors and cell adhesion molecules across the
39   Functional characterization of two bed bug odorant receptors and co-receptors in response to human
40 rplay of odorant-binding proteins (OBPs) and odorant receptors and disrupting the normal responses to
41                We identified agonists for 18 odorant receptors and found that 63% of the odorant rece
42 se odor cues occurs through the interplay of odorant receptors and odorant-binding proteins (OBPs) th
43 elegans (most notably through a reduction of odorant receptors and other gene families), yet it has a
44 ear how chemical features encoded by diverse odorant receptors and segregated glomeruli in the main o
45 pattern shown to include responses from both odorant receptors and trace-amine associated receptors,
46 erologous expression system involving tagged odorant receptors and various accessory proteins promise
47 Gene family expansions (e.g., 344 functional odorant receptors) and pseudogene accumulation in chemor
48 ablished cell lines stably expressing insect odorant receptors are able to detect odorants with consi
49                           Interestingly, the odorant receptors are also involved in a number of devel
50                                              Odorant receptors are among the fastest evolving genes i
51 pha)s or G(alpha)q pathways; and that insect odorant receptors are G-protein-coupled receptors or odo
52                                       Insect odorant receptors are heteromeric odorant-gated cation c
53                          The OR class insect odorant receptors are ligand-gated ion channels comprise
54 SNs expressing about 1000 different types of odorant receptors are precisely organized and sorted out
55 ot differences in pheromone detection by the odorant receptors, are primarily responsible for the beh
56 , based on Sf21 cell lines expressing insect odorant receptors, are sensitive to the level of several
57 dentifies the dynamic expression of a single odorant receptor as a molecular mechanism for context-de
58  odorant identity and concentration using an odorant-receptor binding rate tensor, modulated by the o
59                      Humans have ~400 intact odorant receptors, but each individual has a unique set
60 rom direct activation of seven-transmembrane odorant receptors by odor molecules.
61           Perinatal expression of transgenic odorant receptor causes rerouting of like axons to new g
62  of the C. elegans amphid apparatus serve as odorant receptor cells and regulate neuronal output and
63 ch olfactory receptor neurons expressing the odorant receptor co-receptor (Orco) gene are labelled wi
64  odorant receptors (ORs) contain a conserved odorant receptor co-receptor (Orco) subunit which is an
65 (DEET) and IR3535 did not activate Anopheles odorant receptor co-receptor (Orco)-expressing olfactory
66 /Or13 were each co-expressed with Agam/Orco (odorant receptor co-receptor subunit) in Xenopus oocytes
67                          A small fraction of odorant-receptor combinations elicit remarkably long res
68  Odor receptor (Or) repertoire, yielding 525 odorant-receptor combinations.
69                        The functional insect odorant receptor complex consists of a common co-recepto
70  odor-evoked currents mediated by the insect odorant receptor complex, comprising a ligand-binding su
71 odour-gated ion channel formed by the insect odorant receptor complex.
72 ry systems, which in addition to a family of odorant receptors, contains an approximately equal numbe
73                                 In vivo, the odorant receptor coreceptor (Orco) is an obligatory comp
74 and characterized several antagonists of the odorant receptor coreceptor of the African malaria vecto
75 MP, or IP3 as second messengers; that insect odorant receptors couple to G(alpha)s or G(alpha)q pathw
76 nt 3535, and p-menthan-3,8-diol activate the odorant receptor CquiOR136 of the southern house mosquit
77 by the odorant concentration profile, and an odorant-receptor dissociation rate tensor, and quantitat
78 ew experiments for massively identifying the odorant-receptor dissociation rates of relevance to flie
79 gets for sensory neurons expressing specific odorant receptors during a critical period in the format
80 n about the functional changes of individual odorant receptors during evolution.
81 city of the interaction between odorants and odorant receptors expressed in different olfactory recep
82 rates an effective approach to deorphanizing odorant receptors expressed in neurons located in interm
83 ives from the existence of a large family of odorant receptors expressed in the cilia of the olfactor
84  with an earlier study, does not contain the odorant receptors expressed in the male antenna that det
85  deorphanize a subset of putative Drosophila odorant receptors expressed in trichoid sensilla using a
86  apical zone of olfactory marker protein and odorant receptor-expressing cells.
87 ory bulb and sort from among 1,000 different odorant receptor-expressing types to converge upon the s
88 ells, previous studies have linked efficient odorant receptor expression with N-terminal modification
89                         Because of increased odorant receptor expression, daf-2(e1370) mutants prefer
90 ted in the nasal olfactory epithelium by the odorant receptor family, whose approximately 1,000 membe
91 insights concerning the molecular aspects of odorant receptor function.
92 lfactory sensory neuron expresses one single odorant receptor gene allele from a large family of odor
93 s and determined the positions of homologous odorant receptor gene alleles in relation to different n
94 d that the two homologous alleles of a given odorant receptor gene are frequently segregated to separ
95                                         Each odorant receptor gene defines a unique type of olfactory
96   Here, we demonstrate in the zebrafish that odorant receptor gene silencing is dependent on receptor
97 The signal transduction mechanism subserving odorant receptor gene silencing remains obscure, however
98 nsory neurons (OSNs) that express a specific odorant receptor gene.
99 ry neurons (OSNs) expressing the same unique odorant-receptor gene converge onto the same glomeruli i
100 ture neurons expressed only one of the ~1000 odorant receptor genes (Olfrs) available, and at a high
101 estigated whether genetic variation in human odorant receptor genes accounts in part for variation in
102 and sufficient to suppress the expression of odorant receptor genes and likely acts through histone m
103  variants that arise during the evolution of odorant receptor genes can contribute to individual vari
104 histone methylation to maintain the silenced odorant receptor genes in transcriptionally inactive het
105                                 Mutations in odorant receptor genes predict olfactory perception of c
106 st one out of a possible approximately 1,000 odorant receptor genes, reflecting an exquisite mode of
107 ay play a critical role in the expression of odorant receptor genes.
108  receptor gene allele from a large family of odorant receptor genes.
109 led by a single QTL containing at least four odorant receptor genes.
110 ory neurons causes them to express different odorant receptor genes.
111 l cavity, allowing full expression of a huge odorant receptor genome.
112                         Insect gustatory and odorant receptors (GRs and ORs) form a superfamily of no
113 lfactory receptor neurons expressing a given odorant receptor has convergent axonal projections to tw
114 , we reveal that transgenic expression of an odorant receptor has non-cell autonomous effects on axon
115                          The accuracy of the odorant receptor heterologous expression system involvin
116  odor binding to ORco, the common subunit of odorant receptor heteromers, may allosterically alter ol
117 such as H. saltator, the 9-exon subfamily of odorant receptors (HsOrs) responds to CHCs, and ectopic
118 eview will focus on the diverse roles of the odorant receptor in the function and development of the
119 e first link between the function of a human odorant receptor in vitro and odour perception.
120                              Mutants lacking odorant receptors in dendrites display constant low spik
121 has been challenging to functionally express odorant receptors in heterologous cells, previous studie
122                                              Odorant receptors in the MOE are coupled to the type 3 a
123 ave enhanced representation for M71 or MOR23 odorant receptors in the olfactory system, as is observe
124                                              Odorant receptors in the periphery map precisely onto ol
125 t, and can amplify odorant signaling through odorant receptors in vitro However, the functional signi
126 e mechanisms underlying regulation of insect odorant receptors in vivoSIGNIFICANCE STATEMENT We have
127                                         Like odorant receptors, individual mouse TAARs are expressed
128 s by reducing the constitutive activities of odorant receptors, inhibiting the basal spike firing in
129                        In one model, once an odorant receptor is chosen for expression, other recepto
130                   Thus, the activation of an odorant receptor is essential for blood progenitor maint
131                 Here, we show that the Or47b odorant receptor is required for the copulation advantag
132 nd globally altered so that only one type of odorant receptor is universally expressed.
133 ein-coupled receptor that, unlike most other odorant receptors, is expressed in a large population of
134                             The discovery of odorant receptors led to endeavors in matching them with
135 on that such odorants would activate class I odorant receptors located in zone 1 of the olfactory epi
136  95% of the sensory neurons express a single odorant receptor, M71.
137                                           An odorant receptor map in mammals that is constructed by t
138       Together, these data indicate that the odorant receptor map is developmentally linked to the ol
139 n the dorsal and ventral subdivisions of the odorant receptor map.
140 ing information from distinct regions of the odorant receptor map.
141 ant receptor, suggesting that other types of odorant receptors might exist.
142 ndritic knobs of mouse OSNs that express the odorant receptor MOR23 along with the green fluorescent
143 nnal sensillae from wild-type, clock mutant, odorant-receptor mutant, and G protein-coupled receptor
144 has been conducted to characterize different odorant receptors, neuroanatomy and odorant response pro
145   KEY POINTS: The release probability of the odorant receptor neuron (ORN) is reportedly one of the h
146                                              Odorant receptor neurons (ORNs) express specific odorant
147 ic cue by insulin are integrated at specific odorant receptor neurons (ORNs) to modulate olfactory se
148 li in the antennal lobe region innervated by odorant receptor neurons from basiconic sensilla.
149                Thus, direct activation of an odorant receptor, not an ionotropic receptor, is necessa
150 n odor (acetophenone) that activates a known odorant receptor (Olfr151) was used to condition F0 mice
151              Chemoreception, mediated by the odorant receptors on the membrane of olfactory sensory n
152 subset of the olfactory sensory neurons, the odorant receptor ONE-GC guanylate cyclase is a central t
153 ila olfactory sensory neurons express either odorant receptors or ionotropic glutamate receptors (IRs
154  and Ggamma(13) but not of G protein-coupled odorant receptors or other components of the odorant sig
155  in insects involves heterodimers between an odorant receptor (OR) and a conserved seven-transmembran
156 urbation of OSN function via knockout of the odorant receptor (OR) co-receptor, Orco, results in dras
157                            Recent studies of odorant receptor (OR) expression, synaptic organization,
158 reveals a remarkable expansion of the insect odorant receptor (Or) family relative to the repertoires
159 e sense of smell is mediated by GPCRs in the odorant receptor (OR) family.
160 identified a honey bee [Apis mellifera (Am)] odorant receptor (Or) for the queen substance 9-oxo-2-de
161 udied to date, neurons that express the same odorant receptor (Or) gene are scattered across sensory
162 sensory neurons (OSNs) that express the same odorant receptor (OR) gene coalesce into one or a few gl
163                   The expression of a single odorant receptor (OR) gene from a large gene family in i
164 sensory neurons (OSNs) expressing a specific odorant receptor (OR) gene send axonal projections to sp
165 ies on the expression of approximately 1,100 odorant receptor (OR) genes across millions of olfactory
166                                              Odorant receptor (OR) genes and proteins represent more
167 ence variants in six Drosophila melanogaster odorant receptor (Or) genes are associated with variatio
168                                Studies using odorant receptor (OR) genes have provided insight into t
169                 From the approximately 1,200 odorant receptor (OR) genes in the mouse genome, an olfa
170 ants have evolved a large and novel clade of odorant receptor (OR) genes to perceive hydrocarbon-base
171 ound for the ratio of the number of class II odorant receptor (OR) genes to that of class I genes, bu
172 tects myriad volatile chemicals using >1,000 odorant receptor (OR) genes, which are organized into tw
173 istry coincides with rapid divergence in few odorant receptor (OR) genes.
174 ntennae-rich olfactory genes, second only to odorant receptor (OR) genes.
175 neuron of one allele of only one of the 1000 odorant receptor (OR) genes.
176 y sensory neurons (OSNs) expressing the same odorant receptor (OR) into the same glomeruli.
177 haviors requires the activity of heteromeric odorant receptor (OR) ion channel complexes and ligands
178  the OB, axons from OSNs expressing the same odorant receptor (OR) sort and converge to form molecula
179 pressed a male-specific, pheromone-sensitive odorant receptor (OR), BmorOR1, from the silkworm moth B
180 sensory neurons (OSNs) that express the same odorant receptor (OR).
181                                              Odorant receptors (OR) are strongly implicated in coales
182 nsable for the responses of the conventional odorant receptor OR22a to its short hydrocarbon fruit es
183 mentalization of Ca(2+) signals dictates the odorant receptor OR2W3-induced ASM relaxation and identi
184 manipulation of olfactory neurons expressing odorant receptor Or65a.
185                   The T1 neurons express the odorant receptor Or67d and are exquisitely tuned to cVA
186 et of Fru(+) olfactory neurons expresses the odorant receptor Or67d and responds to the male-specific
187 own to be required for cVA reception are the odorant receptor Or67d and the extracellular pheromone-b
188 ink between the in vitro function of a human odorant receptor, OR7D4, and in vivo olfactory perceptio
189                    Here we show that a human odorant receptor, OR7D4, is selectively activated in vit
190                     Furthermore, mutation of odorant receptor Or83b resulted in severe olfactory defe
191 potent and specific activator for the orphan odorant receptor Or83c.
192 he mouse nose is mediated by 1,000 different odorant receptors (ORs) and 14 trace amine-associated re
193 nts evolved via expansions in the numbers of odorant receptors (ORs) and antennal lobe glomeruli.
194       The insect chemosensory repertoires of Odorant Receptors (ORs) and Gustatory Receptors (GRs) to
195 lions of odorants requires a large number of odorant receptors (ORs) and that each OR interacts selec
196 ncoded by large gene families, including the odorant receptors (ORs) and the variant ionotropic recep
197  mouse nose is mediated by >1, 000 different odorant receptors (ORs) and trace amine-associated recep
198  to examine the repertoires of rat and mouse odorant receptors (ORs) and type 1 pheromone receptors (
199 anntenogram (EAG) responses, suggesting that odorant receptors (ORs) and/or OR-dependent processes ar
200 A fundamental question in olfaction is which odorant receptors (ORs) are activated by a given odorant
201                                       Insect odorant receptors (ORs) are believed to be a complex of
202                                    Mammalian odorant receptors (ORs) are crucial for establishing the
203                                           As odorant receptors (ORs) are thought to be critical deter
204                                              Odorant receptors (ORs) belong to a large gene family of
205             Here we report the expression of odorant receptors (ORs) belonging to the superfamily of
206                                The mammalian odorant receptors (ORs) comprise a large family of G pro
207                                       Insect odorant receptors (ORs) comprise an enormous protein fam
208    Moreover, the mechanisms of expression of odorant receptors (ORs) constitute one of the biggest en
209 ble odorant specificity subunits, all insect odorant receptors (ORs) contain a conserved odorant rece
210 ant receptor neurons (ORNs) express specific odorant receptors (ORs) encoded by a dramatically expand
211 es of volatile components, competing to bind odorant receptors (ORs) expressed in olfactory sensory n
212 erisation of the near-complete repertoire of odorant receptors (Ors) expressed in this tissue, to fra
213                                              Odorant receptors (ORs) for sex pheromone substances hav
214                                              Odorant receptors (ORs) from moths, fruit flies, mosquit
215 of information about the structure of insect odorant receptors (ORs) hinders the development of more
216 rom >240,000 potential volatiles for several Odorant receptors (Ors) in the Drosophila antenna.
217          Ectopic expression and functions of odorant receptors (ORs) in the human body have aroused m
218                                              Odorant receptors (ORs) in the olfactory epithelium bind
219                  The ciliary localization of odorant receptors (ORs) is evolutionary conserved and es
220         The repertoire of approximately 1200 odorant receptors (ORs) is mapped onto the array of appr
221                                Activation of odorant receptors (ORs) leads to adenylyl cyclase III ac
222           Odorants are initially detected by odorant receptors (ORs) on olfactory sensory neurons (OS
223 tinct odors but do not express either insect odorant receptors (ORs) or gustatory receptors (GRs).
224 tory sensory neurons (OSNs), suggesting that odorant receptors (ORs) or OR-dependent processes are un
225 en a challenging task, with their effects on odorant receptors (ORs) remaining a debatable issue.
226 of activated glomeruli, reflecting different odorant receptors (ORs) stimulated in the nose.
227  is thought to recognize odors with multiple odorant receptors (ORs) that are activated by overlappin
228 eded by the paucity of information about the odorant receptors (ORs) that respond to a given odorant
229 lian olfactory system uses a large family of odorant receptors (ORs) to detect and discriminate among
230                  Male moths are endowed with odorant receptors (ORs) to detect species-specific sex p
231 e receptors (M3-Rs) physically interact with odorant receptors (ORs) to promote odour-induced respons
232 hemosensory proteins (CSPs) and 53 candidate odorant receptors (ORs) using a newly generated whole-ge
233  we functionally characterize a subfamily of odorant receptors (Ors) with a nine-exon gene structure
234  an obligatory component for the function of odorant receptors (ORs), a major receptor family involve
235 arities between neurons expressing TAARs and odorant receptors (ORs), but also unexpected differences
236 s of a critical class of chemoreceptors, the odorant receptors (ORs), from the ponerine ant Harpegnat
237    Chemosensory receptor proteins, including odorant receptors (ORs), gustatory receptors (GRs) and i
238 hemosensory receptor families, including the odorant receptors (ORs), membrane proteins that form het
239 sting of distinct patterns of responses from odorant receptors (ORs), trace-amine associated receptor
240 ly of Aedes aegypti olfactory receptors, the odorant receptors (ORs), was not sufficient to reduce ho
241  discriminated through a divergent family of odorant receptors (ORs).
242 of a single member of a very large family of odorant receptors (ORs).
243 dors via a large family of G protein-coupled odorant receptors (ORs).
244 lapping zones of OSNs that express different odorant receptors (ORs).
245                                          The odorant receptors (OrXs) Or10a, Or22a, and Or71a from th
246            These effects are specific to the odorant-receptor pair lyral-MOR23: there was no effect o
247 issociation rate is only available for a few odorant-receptor pairs.
248 enable the estimation of the affinity of the odorant-receptor pairs.
249                         We conclude that the odorant receptor pathway is crucial for an anthropophili
250  to examine the contribution of Orco and the odorant receptor pathway to mosquito host selection and
251 sponsible for ensuring the expression of one odorant receptor per olfactory sensory neuron.
252 nsory axons from neurons expressing the same odorant receptor project with high precision to specific
253       Each OSN expresses a single functional odorant receptor protein and projects an axon from the s
254 ade in tracing olfactory perception from the odorant receptor protein to the activity of olfactory ne
255  signals are transduced by a large family of odorant receptor proteins, each of which corresponds to
256               Herein, we present that insect odorant receptors reconstituted into the lipid bilayers
257                                     Yet many odorant receptors remain only partially characterized, a
258 tion of individual odors with subsets of the odorant receptor repertoire and mode of signaling that a
259  of S. flava and characterized this species' odorant receptor repertoire.
260 th the corresponding Drosophila melanogaster odorant receptor repertoire.
261                            This chemosensory odorant receptor response was not mediated by adenylyl c
262 tional level of synergism, inducing enhanced odorant receptor responses to odorants and thus defining
263 trates that the currently available data for odorant-receptor responses only enable the estimation of
264 a et al. in this issue demonstrates that the odorant receptor's level of intrinsic activity-in the ab
265  activation of ionotropic receptor IR40a vs. odorant receptor(s).
266                                              Odorant receptor sequence, G-protein cAMP signaling, and
267 or, interacts with Galphaolf and can amplify odorant receptor signal transduction in vitro To explore
268                                              Odorant receptors signal through the olfactory-specific
269 ic) cell division, and Galpha(olf)-dependent odorant receptor signaling.
270 y bulb, lateral inhibition may occur between odorant receptor-specific glomeruli that are linked anat
271  called protoglomeruli well before they form odorant receptor-specific glomeruli.
272           Transgenic mice labeled at the M71 odorant receptor (specifically activated by the odorant
273            In the olfactory epithelium (OE), odorant receptor stimulation generates cAMP signals that
274 mic criteria was carried out across discrete odorant receptor subfamilies.
275 erly called OR83B), and one or more variable odorant receptor subunits that confer odour selectivity.
276 ensory neurons express a seven transmembrane odorant receptor, suggesting that other types of odorant
277 structed based on the responses from all the odorant receptors tested revealed that odorants within t
278 factory neuron is determined by the singular odorant receptor that it expresses.
279 ork identifies an unanticipated cofactor for odorant receptors that is likely to have a widespread ro
280  by inhibiting subsets of heteromeric insect odorant receptors that require the OR83b co-receptor.
281 rved, in neurons that express the M71 or M72 odorant receptors, that Nrp1 inactivation leads to two d
282 ulb in stereotyped patterns according to the odorant receptors they express.
283  the sensitivity of an odour-specific insect odorant receptor to odour ligands and DEET.
284             We investigated the responses of odorant receptors to a large spectrum of semiochemicals,
285 s, we suggest that SNMP acts in concert with odorant receptors to capture pheromone molecules on the
286 e electro-physiological responses of bed bug odorant receptors to human odorants with the Xenopus exp
287 nts and theory that relate the properties of odorant receptors to the detailed wiring diagram of the
288 ry system function, from the distribution of odorant receptors to the functional organization of cent
289 tory epithelium (MOE) depends on coupling of odorant receptors to the type 3 adenylyl cyclase (AC3) i
290                                              Odorant receptors typically obey the "one receptor, one
291  odorant receptors and found that 63% of the odorant receptors we examined had polymorphisms that alt
292 actory sensory neurons (OSNs) with a defined odorant receptor, we demonstrate that OSNs exhibit funct
293 cally, with the use of Sf21 cells and insect odorant receptors, we demonstrated that the established
294 , and G(alphaolf), a diverse set of untagged odorant receptors were successfully expressed heterologo
295 alization, consistent with being mediated by odorant receptors, whereas amino acid responses overlap
296                     Odorants are detected by odorant receptors, which are located on olfactory sensor
297                                 Orthologs of odorant receptors, which detect yeast volatiles in D. me
298 ge family of G protein-coupled receptors-the odorant receptors-which are the chemical sensors underly
299  contains 21 ORNs and a comparable number of odorant receptors whose properties have been examined in
300 junction with the large repertoire of insect odorant receptors, will aid in the development of practi

 
Page Top