50 resultados para ISDN-käyttäjäosa
Resumo:
A randomized controlled trial was conducted to compare the costs of realtime teleneurology with the cost of conventional neurological care. Two district hospitals in Northern Ireland were equipped with videoconferencing units and were connected to the regional neurological centre by ISDN at 384 kbit/s. Of 168 patients randomized to the study, 141 kept their appointments (76 male, 65 female). Sixty-five patients were randomized to a conventional consultation while 76 were randomized to a teleconsultation. The average age was 44 years of those seen conventionally and 42 years of those seen by telemedicine. The groups had similar diagnoses. The telemedicine group required more investigations and reviews than the conventional group. The average cost of the conventional consultation was pound 49 compared with pound 72 for the teleconsultation. Realtime teleneurology was not as cost-effective as conventional care.
Resumo:
We have established a realtime fetal tele-ultrasound consultation service in Queensland, which has been integrated into our routine clinical practice, The service, which uses ISDN transmission at 384 kbit/s, allows patients in Townsville to be examined by subspecialists in Brisbane, 1500 km away. For the 90 tele-ultrasound consultations performed for the first 71 patients, 90% of the babies have been delivered, and outcome data have been received on all the pregnancies. All significant anomalies and diagnoses have been confirmed. The referring clinicians would have physically referred 24 of the 71 patients to Brisbane in the absence of telemedicine. A crude cost-benefit calculation suggests that the tele-ultrasound service resulted in a net saving of A$6340, and at the same time enabled almost four times the number of consultations to be carried out.
Resumo:
We have developed a software application to enable interactive rehabilitation via the Internet. The reliability of the telemedicine application was examined by comparing it with face-to-face assessment. The physical outcome measures assessed were knee range of motion, quadriceps muscle strength, limb girth and an assessment of gait. One therapist performed both in-person and Internet-based measurements of all outcome measures on 20 normal subjects. There was good agreement between the two techniques (the 95% limits of agreement included zero for all the variables studied). Internet assessments were conducted at two bandwidths: ISDN at 128 kbit/s and the telephone network at 17 kbit/s. Bandwidth had no significant influence on any of the measures. This study suggests that Internet-based physiotherapy interventions delivered to the home are suitable for further development.
Resumo:
In the B-ISDN there is a provision for four classes of services, all of them supported by a single transport network (the ATM network). Three of these services, the connected oriented (CO) ones, permit connection access control (CAC) but the fourth, the connectionless oriented (CLO) one, does not. Therefore, when CLO service and CO services have to share the same ATM link, a conflict may arise. This is because a bandwidth allocation to obtain maximum statistical gain can damage the contracted ATM quality of service (QOS); and vice versa, in order to guarantee the contracted QOS, the statistical gain have to be sacrificed. The paper presents a performance evaluation study of the influence of the CLO service on a CO service (a circuit emulation service or a variable bit-rate service) when sharing the same link
Resumo:
Iowa Code section 8D.10 requires certain state agencies prepare an annual report to the General Assembly certifying the identified savings associated with that state agency's use of the Iowa Communications Network (ICN). This report covers estimated cost savings related to video conferencing via ICN for the Iowa Department of Transportation (DOT). In January 2012 the Iowa DOT requested the ISDN video circuit be disconnected which closed its ICN account.
Resumo:
PURPOSE: To explore the use of telementoring for distant teaching and training in endovascular aortic aneurysm repair (EVAR). METHODS: According to a prospectively designed study protocol, 48 patients underwent EVAR: the first 12 patients (group A) were treated at a secondary care center by an experienced interventionist, who was training the local team; a further 12 patients (group B) were operated by the local team at their secondary center with telementoring by the experienced operator from an adjacent suite; and the last 24 patients (group C) were operated by the local team with remote telementoring support from the experienced interventionist at a tertiary care center. Telementoring was performed using 3 video sources; images were transmitted using 4 ISDN lines. EVAR was performed using intravascular ultrasound and simultaneous fluoroscopy to obtain road mapping of the abdominal aorta and its branches, as well as for identifying the origins of the renal arteries, assessing the aortic neck, and monitoring the attachment of the stent-graft proximally and distally. RESULTS: Average duration of telementoring was 2.1 hours during the first 12 patients (group B) and 1.2 hours for the remaining 24 patients (group C). There was no difference in procedural duration (127+/-59 minutes in group A, 120+/-4 minutes in group B, and 119+/-39 minutes in group C; p=0.94) or the mean time spent in the ICU (26+/-15 hours in group A, 22+/-2 hours in group B, and 22+/-11 hours for group C; p=0.95). The length of hospital stay (11+/-4 days in group A, 9+/-4 days in group B, and 7+/-1 days in group C; p=0.002) was significantly different only for group C versus A (p=0.002). Only 1 (8.3%) patient (in group A: EVAR performed by the experienced operator) required conversion to open surgery because of iliac artery rupture. This was the only conversion (and the only death) in the entire study group (1/12 in group A versus 0/36 in groups B + C, p=0.31). CONCLUSIONS: Telementoring for EVAR is feasible and shows promising results. It may serve as a model for development of similar projects for teaching other invasive procedures in cardiovascular medicine.
Resumo:
Nokia TETRA –järjestelmä on digitaaliseen tekniikkaan pohjautuva radiopuhelinjärjestelmä, joka on tarkoitettu erityisvaatimuksia omaavien organisaatioiden ammattikäyttöön. Sen tyypillisiä käyttäjiä ovat erilaiset viranomaiset, kuten poliisi, palo- ja pelastuslaitos sekä rajavartiolaitos. Se perustuu avoimeen TETRA-standardiin, joka määrittelee tärkeimmät palvelut ja rajapinnat tiettyjen verkkoelementtien välillä. TETRA-järjestelmän käyttöpaikkatyöasemat ja palvelimet perustuvat kaikki samaan Nokia TETRA –rajapintapalvelimen arkkitehtuuriin. Käyttöpaikat tarjoavat tehokkaat toiminnot verkon operatiiviseen käyttöön ja hallintaan. Palvelimet puolestaan tarjoavat ohjelmointirajapintansa kautta kolmansille osapuolille mahdollisuuden luoda TETRA-järjestelmän palveluita käyttäviä sovelluksia. Työn tavoitteena oli tutkia uusien rajapintojen soveltuvuutta sekä selvittää niiden vaikutusta Nokia TETRA –rajapintapalvelimen arkkitehtuuriin. Ensin kartoitettiin nykyisen arkkitehtuurin ongelmat ja puutteet äänikommunikaatioon käytetyssä tiedonsiirrossa, ja äänikommunikaatiossa käyttäjään päin. Näiden ratkaisemiseksi tutkittiin uusia rajapinta-vaihtoehtoja. Parhaiten soveltuvista vaihtoehdoista muodostettiin ratkaisu, jonka vaikutus uuden sukupolven arkkitehtuuriin selvitettiin.
Resumo:
UMTS is a 3rd generation telecommunication system, which introduces new network architecture. The change in the network architecture introduces new logical network nodes and changes the role of existing nodes in the network. This architecture changes the current vertically specialized network into a horizontally layered structure. In practice, the layering means that different levels in network hierarchy are separated, and they communicate over well-specified interfaces. The Connectivity Layer, at the bottom of the UMTS network architecture, contains Media Gateways (MGW). The GSM radio access network and UMTS access network are connected to the connectivity network via a MGW. External networks, e.g. ISDN networks, are accessed via other MGWs. The user plane is transported across the connectivity network between/via MGWs. ATM network is used as the backbone in Ericsson’s UMTS core network release 2.0. The main goal of this thesis is to study how the MGW is used to bridge ATM and TDM networks. The Circuit Emulation Service (CES) for ATM is studied, as the conversion from TDM to ATM is made according it. The transportation is made using AAL2 and the issues that it has with voice traffic are studied. The implementation and usage of TDM switching service in MGW are described in detail.
Resumo:
A telemedicina é definida como a troca de informações utilizando tecnologia de informação e de comunicação em saúde e a distância. Entre as diversas modalidades da telemedicina incluem-se as videoconferências, que permitem a integração em tempo real, recebendo e enviando áudio e vídeo de alta qualidade entre pontos distantes geograficamente. O objetivo deste trabalho é descrever, de maneira simplificada, os sistemas de videoconferências, destacando-se suas aplicações no contexto da telemedicina. Para a realização de videoconferências são necessários equipamentos que façam captura e reprodução de áudio e vídeo, e que tenham possibilidade de conexão com equipamentos similares, como microcomputadores e equipamentos dedicados. Os tipos de conexão para uma videoconferência são: via ISDN (integrated services digital network) ou via IP (internet protocol). A qualidade do áudio e do vídeo e a velocidade são críticas para o sucesso da videoconferência. Experiências internacionais na utilização de equipamentos de videoconferência, inclusive na radiologia e diagnóstico por imagem, já são uma realidade. No Brasil, relatos mostram iniciativas isoladas de telemedicina, em sua maioria incluindo redes universitárias. A videoconferência representa uma excelente ferramenta para a capacitação e atualização do profissional médico, além de proporcionar grande impacto nos custos do atendimento à população.
Resumo:
In the B-ISDN there is a provision for four classes of services, all of them supported by a single transport network (the ATM network). Three of these services, the connected oriented (CO) ones, permit connection access control (CAC) but the fourth, the connectionless oriented (CLO) one, does not. Therefore, when CLO service and CO services have to share the same ATM link, a conflict may arise. This is because a bandwidth allocation to obtain maximum statistical gain can damage the contracted ATM quality of service (QOS); and vice versa, in order to guarantee the contracted QOS, the statistical gain have to be sacrificed. The paper presents a performance evaluation study of the influence of the CLO service on a CO service (a circuit emulation service or a variable bit-rate service) when sharing the same link
Resumo:
We have previously shown that melatonin influences the development of alpha 8 nicotinic acetylcholine receptor (nAChR) by measurement of the acetylcholine-induced increase in the extracellular acidification rate (ECAR) in chick retinal cell cultures. Cellular differentiation that takes place between DIV (days in vitro) 4 and DIV 5 yields cells expressing alpha 8 nAChR and results in a significant increase in the ECAR acetylcholine-induced. Blocking melatonin receptors with luzindole for 48 h suppresses the development of functional alpha 8 nAChR. Here we investigated the time window for the effect of melatonin on retinal cell development in culture, and whether this effect was dependent on an increase in the expression of alpha 8 nAChR. First, we confirmed that luzindole was inhibiting the effects of endogenous melatonin, since it increases 2-[(125)I] iodomelatonin (23 pM) binding sites density in a time-dependent manner. Then we observed that acute (15, 60 min, or 12 h) luzindole treatment did not impair acetylcholine-induced increase in the ECAR mediated by activation of alpha 8 nAChR at DIV 5, while chronic treatment (from DIV 3 or DIV 4 till DIV 5, or DIV 3.5 till DIV 4.5) led to a time-dependent reduction of the increase in the acetylcholine-induced ECAR. The binding parameters for [(125)I]-alpha-bungarotoxin (10 nM) sites in membrane were unaffected by melatonin suppression that started at DIV 3. Thus, melatonin surges in the time window that occurs at the final stages of chick retinal cell differentiation in culture is essential for development of the cells expressing alpha 8 nAChR subtype in full functional form. (C) 2010 ISDN. Published by Elsevier Ltd. All rights reserved.
Resumo:
We investigated the possible participation of TRPV1 channels in retinal apoptosis and overall development. Retinas from newborn, male albino rats were treated in vitro with capsazepine, a TRPV1 antagonist. The expression of cell cycle markers was not changed after TRPV1 blockade, whereas capsazepine reduced the number of apoptotic cells throughout the retina,increased ERK1/2 and p38 phosphorylation and slightly reduced JNK phosphorylation. The expression of BAD, Bcl-2, as well as integral and cleaved capsase-3 were similar in all experimental conditions. Newborn rats were kept for 2 months after receiving high doses of capsazepine. In their retinas, calbindin and parvalbumin protein levels were upregulated, but only the number of amacrine-like, parvalbumin-positive cells was increased. The numbers of calretinin, calbindin, ChAT, vimentin, PKC-alpha and GABA-positive cells were similar in both conditions. Protein expression of synapsin Ib was also increased in the retinas of capsazepine-treated rats. Calretinin, vimentin, GFAP, synapsin Ia, synaptophysin and light neurofilament protein levels were not changed when compared to control values. Our results indicate that TRPV1 channels play a role in the control of the early apoptosis that occur during retinal development, which might be dependent on MAPK signaling. Moreover, it seems that TRPV1 function might be important for neuronal and synaptic maturation in the retina. (C) 2011 ISDN. Published by Elsevier Ltd. All rights reserved.
Resumo:
We have used P19 embryonal carcinoma cells as in vitro model for early neurogenesis to study ionotropic P2X and metabotropic P2Y receptor-induced Ca2+ transients and their participation in induction of proliferation and differentiation. In embryonic P19 cells, P2Y(1), P2Y(2) and P2X(4) receptors or P2X-heteromultimers with similar P2X4 pharmacology were responsible for ATP and ATP analogue-induced Ca2+ transients. In neuronal-differentiated cells, P2Y(2), P2Y(6), P2X(2) and possibly P2X(2)/P2X(6) heteromeric receptors were the major mediators of the elevations in intracellular free calcium concentration [Ca2+](i). We have collected evidence for the involvement of metabotropic purinergic receptors in proliferation induction of undifferentiated and neural progenitor cells by using a BrdU-incorporation assay. ATP-, UTP-, ADP-, 2-MeS-ATP- and ADP-beta S-induced proliferation in P19 cells was mediated by P2Y, and P2Y2 receptors as judged from pharmacological profiles of receptor responses. ATP-provoked acceleration of neuronal differentiation, determined by analysis of nestin and neuron-specific enolase gene and protein expression, also resulted from P2Y, and P2Y2 receptor activation. Proliferation- and differentiation-induction involved the activation of inositol-trisphosphate sensitive intracellular Ca2+ stores. (C) 2008 ISDN. Published by Elsevier Ltd. All rights reserved.
Connexin-mediated communication controls cell proliferation and is essential in retinal histogenesis
Resumo:
Connexin (Cx) channels and hemichannels are involved in essential processes during nervous system development such as apoptosis, propagation of spontaneous activity and interkinetic nuclear movement. In the first part of this study, we extensively characterized Cx gene and protein expression during retinal histogenesis. We observed distinct spatio-temporal patterns among Studied Cx and an overriding, ubiquitous presence of Cx45 in progenitor cells. The role of Cx-mediated communication was assessed by using broad-spectrum (carbenoxotone, CBX) and Cx36/Cx50 channel-specific (quinine) blockers. In vivo application of CBX, but not quinine, caused remarkable reduction in retinal thickness, suggesting changes in cell proliferation/apoptosis ratio. Indeed, we observed a decreased number of mitotic cells in CBX-injected retinas, with no significant changes in the expression of PCNA, a marker for cells in proliferative state. Taken together, Our results pointed a pivotal role of Cx45 in the developing retina. Moreover, this study revealed that Cx-mediated Communication is essential in retinal histogenesis, particularly in the control of cell proliferation. (C) 2009 ISDN. Published by Elsevier Ltd. All rights reserved.
Resumo:
The present study aimed to analyze the gene and protein expression and the pattern of distribution of the vanilloid receptors TRPV1 and TRPV2 in the developing rat retina. During the early phases of development, TRPV1 was found mainly in the neuroblastic layer of the retina and in the pigmented epithelium. In the adult, TRPV1 was found in microglial cells, blood vessels, astrocytes and in neuronal structures, namely synaptic boutons of both retina] plexiform layers, as well as in cell bodies of the inner nuclear layer and the ganglion cell layer. The pattern of distribution of TRPV1 was mainly punctate, and there was higher TRPV1 labeling in the peripheral retina than in central regions. TRPV2 expression was quite distinct. its expression was virtually undetectable by immunoblotting before P1, and that receptor was found by immunohistochemistry only by postnatal day 15 (PI 5). RNA and protein analysis showed that the adult levels are only reached by P60, which includes small processes in the retinal plexiform layers, and labeled cellular bodies in the inner nuclear layer and the ganglion cell layer. There was no overlapping between the signal observed for both receptors. in conclusion, our results showed that the patterns of distribution of TRPV1 and TRPV2 are different during the development of the rat retina, suggesting that they have specific roles in both visual processing and in providing specific cues to neural development. (C) 2009 ISDN. Published by Elsevier Ltd. All rights reserved.