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1.
Eur Rev Med Pharmacol Sci ; 28(1): 126-135, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38235864

RESUMO

OBJECTIVE: This study aimed at determining the optimal dose combination of alfentanil and propofol for outpatient abortion anesthesia. PATIENTS AND METHODS: The study was separated into two parts. In the first part, patients were to determine the median effective dose (ED50) and the 95% effective dose (ED95) of alfentanil in combination with 2.5 mg·kg-1 propofol to inhibit body movements during the abortion using the Dixon up-and-down sequential allocation method. In the second part, 170 patients were randomly divided into group C (2.0 mg·kg-1 propofol with alfentanil 12.16 µg·kg-1) and group E (2.5 mg·kg-1 propofol with its ED95) to compare the anesthetic effect. The primary outcome was the sedation level during general anesthesia. The secondary outcomes were circulation, respiratory complications, and postoperative recovery quality. RESULTS: The ED50 and the ED95 values of alfentanil were 3.37 µg·kg-1 (95% CI: 2.58-3.97 µg·kg-1) and 4.68 µg·kg-1 (95% CI: 4.04-9.32 µg·kg-1). The frequency of deep sedation in group E was significantly higher than in group C (76.5% vs. 60%). Patients in group C showed more wakefulness even during the surgery (14.3% vs. 4.4%). The results of our exploratory analyses did not reveal differences in respiratory depression, circulatory depression, postoperative side effects, or recovery outcomes. CONCLUSIONS: The combination of 2.5 mg·kg-1 propofol and 4.68 µg·kg-1 alfentanil produces a better sedative effect than the combination of 2.0 mg·kg-1 propofol and 12.16 µg·kg-1 alfentanil without increasing additional risks associated with anesthesia.


Assuntos
Propofol , Gravidez , Feminino , Humanos , Alfentanil/efeitos adversos , Pacientes Ambulatoriais , Estudos Prospectivos , Método Duplo-Cego
2.
Cancer Gene Ther ; 24(7): 304-308, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28731026

RESUMO

In this study, we characterized the role of HA117, a novel gene we previously identified, in drug resistance in vitro and in vivo. Briefly, CT26 cells expressing HA117 were obtained by infection with a recombinant adenovirus, and tested for drug sensitivity by methyl thiazolyl tetrazolium assay. In addition, the effect of HA117 on drug sensitivity was assessed in CT26 colon tumors transplanted into nude mice. In vitro, expression of HA117 increased the resistance of CT26 cells to 5-fluorouracil 2.75 times (P<0.05). Similarly, expression of HA117 in subcutaneously xenografted CT26 colon cancer significantly lowered its sensitivity to 5-fluorouracil (P<0.05). Collectively, the results suggest that HA117 regulates the development of drug resistance in CT26 cells in vitro and in vivo.


Assuntos
Neoplasias do Colo/genética , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Neoplasias/genética , Adenoviridae/genética , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Neoplasias do Colo/patologia , Modelos Animais de Doenças , Feminino , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica , Vetores Genéticos/genética , Camundongos , Transdução Genética , Carga Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Zhonghua Jie He He Hu Xi Za Zhi ; 40(3): 182-187, 2017 Mar 12.
Artigo em Chinês | MEDLINE | ID: mdl-28297812

RESUMO

Objective: To study the regulative effects of Aspergillus fumigatus (A.fumigatus) on expression of glucocorticoid receptor (GCR) in asthmatic rats. Methods: Wistar rats were randomly divided into 4 groups: a normal control group (UC), a normal control with A. fumigatus group (UC+ AF), an OVA group (OVA), and an OVA with A. fumigatus group (OVA+ AF). OVA and OVA+ AF groups were sensitized and challenged with OVA to establish asthmatic models. UC and UC+ AF groups were given normal saline as controls. After the last challenge, OVA+ AF and UC+ AF groups were given A. fumigatus spores intranasally. Airway hyper-responsiveness, eosinophil percentage (Eos%) and serum IgE level were measured to confirm the establishment of asthmatic models. Sections of pulmonary tissue were stained with hematoxylin-eosin (HE) and the expression of GCR mRNA and protein in lung tissues were measured by qRT-PCR and Western blot. Lung tissues and blood were plated on the potato dextrose agar(PDA)medium and cultured for 24 h to measure the number of colony. Results: The Penh value, Eos% in BALF and serum IgE level in UC+ AF group were slightly higher than those in the UC group (all the P>0.05). The Penh value, Eos% in BALF and serum IgE level in OVA group were significantly higher than those in the UC group (all the P<0.05). The Penh value in OVA+ AF group was significantly increased compared with the OVA group at the concentration of 25 g/L and 50 g/L of methacholine (all the P>0.05). Pulmonary histology revealed that both OVA group and OVA+ AF group showed high levels of inflammatory cell infiltration of bronchus and lung vessels, interstitial edema and smooth muscle thickening, while the UC and UC + AF groups were normal. Compared with the UC group, the expressions of GCR mRNA and protein in UC+ AF group and OVA group were decreased significantly (GCR mRNA in UC, UC+ AF and OVA group were 0.93±0.15, 0.65±0.10, 0.72±0.22, respectively, F=10.744, P<0.01; GCR protein in UC, UC+ AF and OVA group were 100±0, 89±8, 82±15, respectively, F=18.939, P<0.01). The expressions of GCR mRNA and protein in OVA+ AF group were further decreased than those in OVA group (GCR mRNA: OVA group: 0.72±0.22 vs OVA+ AF group: 0.52±0.08, t=2.462, P<0.05; GCR protein: OVA group: 81.88±15.41 vs OVA+ AF group: 59.09±7.60, t=2.997, P<0.05). The ratio of A. fumigatus colonization in lung tissues in OVA+ AF group (4/8) was higher than the UC+ AF group (0/8). Conclusion:A. fumigatus exposure can down-regulate the expression of GCR in the lung, which maybe an important mechanism of steroid-resistant asthma.


Assuntos
Aspergillus fumigatus , Asma/metabolismo , Pulmão/metabolismo , Receptores de Glucocorticoides/metabolismo , Animais , Brônquios , Líquido da Lavagem Broncoalveolar , Contagem de Leucócitos , Pulmão/microbiologia , Camundongos Endogâmicos BALB C , Ratos , Ratos Wistar
4.
Int J Cosmet Sci ; 37(3): 321-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25639473

RESUMO

OBJECTIVES: Salidroside, the predominant component of a Chinese herbal medicine, Rhodiola rosea L., becomes an attractive bio-agent due to its multifunction. Although it is well proposed that this herbal medicine may have photoprotective effect according to the folk hearsay, the direct supportive experimental evidences linking the drug with skin ageing have rarely been reported so far. The study was conducted to investigate the photoprotective role of salidrosdie and its related mechanisms in vitro. METHODS: First, a premature senescence model induced by UVB irradiation (250 mJ cm(-2)) in human dermal fibroblasts (HDFs) was established, and senescent phenotypes were evaluated by cell morphology, cell proliferation, senescence-associated beta-galactosidase (SA-ß-gal) activity and cell cycle distribution. Then the photoprotective effect of salidroside was investigated. Cells were pre-treated with various doses of salidroside (1, 5 and 10 µM) followed by the sublethal dosage of UVB exposure and then were harvested for various detections, including senescence-associated phenotypes and molecules, alteration of oxidative stress, matrix metalloproteinase-1 (MMP-1) secretion and inflammatory response. RESULTS: Pre-treatment of salidroside dose dependently reversed the senescent state of HDFs induced by UVB as evidenced by elevated cell viability, decreased SA-ß-gal activity and relieving of G1/G0 cell cycle arrest. UVB-induced increased protein expression of cyclin-dependent kinase (CDK) inhibitors p21(WAF) (1) and p16(INK) (4) was also repressed by salidrosdie treatment in a dose-dependent manner. Meanwhile, the increment of malondialdehyde (MDA) level in UVB-irradiated HDFs was inhibited upon salidroside treatment. Additionally, salidroside significantly attenuated UVB-induced synthesis of MMP-1 as well as the production of IL-6 and TNF-α in HDFs. CONCLUSION: Our data provided the evidences for the protective role of salidroside against UVB-induced premature senescence in HDFs probably via its anti-oxidative property and inhibition on production of MMP-1 and pro-inflammatory cytokines, which indicated its potential utilization as an active ingredient in the preparation of photoprotective formulation.


Assuntos
Senescência Celular/efeitos dos fármacos , Glucosídeos/farmacologia , Fenóis/farmacologia , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Raios Ultravioleta , Células Cultivadas , Humanos , Mediadores da Inflamação/metabolismo , Metaloproteinase 1 da Matriz/metabolismo , Estresse Oxidativo , Pele/citologia , Pele/metabolismo
5.
Opt Express ; 20(19): 21089-100, 2012 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-23037232

RESUMO

Reflective electro-absorption modulation-intensity modulators (REAM-IMs) are utilized, for the first time, to experimentally demonstrate colorless ONUs in single-fiber-based, bidirectional, intensity-modulation and direct-detection (IMDD), optical OFDM PONs (OOFDM-PONs) incorporating 25 km SSMFs and OLT-side-seeded CW optical signals. The colorlessness of the REAM-IMs is characterized, based on which optimum REAM-IM operating conditions are identified. In the aforementioned PON architecture, 10Gb/s colorless upstream transmissions of end-to-end real-time OOFDM signals are successfully achieved for various wavelengths within the entire C-band. Over such a wavelength window, corresponding minimum received optical powers at the FEC limit vary in a range as small as <0.5 dB. In addition, experimental measurements also indicate that Rayleigh backscattering imposes a 2.8 dB optical power penalty on the 10 Gb/s over 25 km upstream OOFDM signal transmission. Furthermore, making use of on-line adaptive bit and power loading, a linear trade-off between aggregated signal line rate and optical power budget is observed, which shows that, for the present PON system, a 10% reduction in signal line rate can improve the optical power budget by 2.6 dB.

6.
Opt Express ; 19(21): 20557-70, 2011 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-21997063

RESUMO

End-to-end real-time experimental demonstrations are reported, for the first time, of aggregated 11.25Gb/s over 26.4km standard SMF, optical orthogonal frequency division multiple access (OOFDMA) PONs with adaptive dynamic bandwidth allocation (DBA). The demonstrated intensity-modulation and direct-detection (IMDD) OOFDMA PON system consists of two optical network units (ONUs), each of which employs a DFB-based directly modulated laser (DML) or a VCSEL-based DML for modulating upstream signals. Extensive experimental explorations of dynamic OOFDMA PON system properties are undertaken utilizing identified optimum DML operating conditions. It is shown that, for simultaneously achieving acceptable BERs for all upstream signals, the OOFDMA PON system has a >3dB dynamic ONU launch power variation range, and the BER performance of the system is insusceptible to any upstream symbol offsets slightly smaller than the adopted cyclic prefix. In addition, experimental results also indicate that, in addition to maximizing the aggregated system transmission capacity, adaptive DBA can also effectively reduce imperfections in transmission channel properties without affecting signal bit rates offered to individual ONUs.

7.
Cancer Gene Ther ; 18(9): 655-62, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21720420

RESUMO

A novel gene, HA117, was discovered in our previous work. Using the pSOS-HUS vector method which we designed at previous study, we screened for small interfering RNAs (siRNAs) that targeted HA117. The pSOS-HUS siRNA screening results were verified and a delivery system was developed that contained a recombinant adenovirus carrying DNA templates for the transcription of the HA117 siRNAs. Of five pairs of DNA templates, siRNA transcribed from HAi5 produced the strongest effect against HA117. A recombinant adenovirus containing HAi5 (Ad-HAi5) was successfully constructed and evaluated. This work has laid the foundation for further study of HA117 gene function using RNA interference technology and has showed the pSOS-HUS vector method was successfully utilized as a rapid and effective screen of siRNAs for a target gene.


Assuntos
Adenoviridae/genética , Vetores Genéticos/genética , Proteínas/metabolismo , RNA Interferente Pequeno/fisiologia , Linhagem Celular , Humanos , Proteínas/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Opt Express ; 19(4): 2979-88, 2011 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-21369122

RESUMO

The feasibility of utilising low-cost, un-cooled vertical cavity surface-emitting lasers (VCSELs) as intensity modulators in real-time optical OFDM (OOFDM) transceivers is experimentally explored, for the first time, in terms of achievable signal bit rates, physical mechanisms limiting the transceiver performance and performance robustness. End-to-end real-time transmission of 11.25 Gb/s 64-QAM-encoded OOFDM signals over simple intensity modulation and direct detection, 25 km SSMF PON systems is experimentally demonstrated with a power penalty of 0.5 dB. The low extinction ratio of the VCSEL intensity-modulated OOFDM signal is identified to be the dominant factor determining the maximum obtainable transmission performance. Experimental investigations indicate that, in addition to the enhanced transceiver performance, adaptive power loading can also significantly improve the system performance robustness to variations in VCSEL operating conditions. As a direct result, the aforementioned capacity versus reach performance is still retained over a wide VCSEL bias (driving) current (voltage) range of 4.5 mA to 9 mA (275 mVpp to 320 mVpp). This work is of great value as it demonstrates the possibility of future mass production of cost-effective OOFDM transceivers for PON applications.

9.
Opt Express ; 18(20): 21100-10, 2010 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-20941006

RESUMO

A simple optical OFDM (OOFDM) synchronization technique utilizing subtraction and Gaussian windowing at the symbol rate is proposed and implemented in FPGA-based OOFDM receivers. End-to-end real-time symbol synchronization of 128-QAM-encoded OOFDM signals at raw bit rates of 6.56Gb/s is experimentally demonstrated, for the first time, over directly modulated DFB laser-based 25km SMF intensity modulation and direct detection (IMDD) systems. Experimental investigations show that the proposed synchronisation technique offers a number of salient advantages including low complexity, fast tracking speed, high accuracy and suitability for high-capacity optical transmission systems.

10.
Opt Express ; 18(10): 9791-808, 2010 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-20588829

RESUMO

Detailed numerical investigations are undertaken of wavelength reused bidirectional transmission of adaptively modulated optical OFDM (AMOOFDM) signals over a single SMF in a colorless WDM-PON incorporating a semiconductor optical amplifier (SOA) intensity modulator and a reflective SOA (RSOA) intensity modulator in the optical line termination and optical network unit, respectively. A comprehensive theoretical model describing the performance of such network scenarios is, for the first time, developed, taking into account dynamic optical characteristics of SOA and RSOA intensity modulators as well as the effects of Rayleigh backscattering (RB) and residual downstream signal-induced crosstalk. The developed model is rigorously verified experimentally in RSOA-based real-time end-to-end OOFDM systems at 7.5 Gb/s. It is shown that the RB noise and crosstalk effects are dominant factors limiting the maximum achievable downstream and upstream transmission performance. Under optimum SOA and RSOA operating conditions as well as practical downstream and upstream optical launch powers, 10 Gb/s downstream and 6 Gb/s upstream over 40 km SMF transmissions of conventional double sideband AMOOFDM signals are feasible without utilizing in-line optical amplification and chromatic dispersion compensation. In particular, the aforementioned transmission performance can be improved to 23 Gb/s downstream and 8 Gb/s upstream over 40 km SMFs when single sideband subcarrier modulation is adopted in the downstream systems.


Assuntos
Amplificadores Eletrônicos , Dispositivos Ópticos , Semicondutores , Processamento de Sinais Assistido por Computador/instrumentação , Telecomunicações/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
11.
Transplant Proc ; 42(5): 1750-4, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20620515

RESUMO

SUBJECT: The aim of this study was to present our institutional experience with the pediatric intensive care unit (PICU) stays of liver recipients to understand prevention of complications. METHODS: This retrospective review included 22 infants who weighed 8.8 kg or less and underwent 23 transplantations. No grafts were from executed prisoners. We summarized the diagnosis, evaluation, medicine usage, and therapeutic intervention associated with subjects experiencing complications of rejection episodes, surgery, or infection during their ICU stay. RESULTS: There was one perioperative death from primary graft nonfunction. The most common postoperative complications were infections, gastrointestinal bleeding, and vascular complications. Rejection episodes occurred among 25% of patients. The most common isolated pathogenic bacteria was Staphylococcus epidermidis. Median initial ICU stay was 10 days. Mean requirement for artificial ventilation was 37.6 hour. Mean times of use of dobutamine, prostaglandin E1, and dopamine was 3.3, 7.5, and 8.8 days, respectively. Parenteral nutrition was started at a mean of 12 hours and oral food intake at a mean of 72 hours. CONCLUSIONS: Although challenging, orthotopic liver transplantation (OLT) in small infants can be successfully performed with meticulous surgical technique and keen postoperative surveillance.


Assuntos
Atresia Biliar/cirurgia , Unidades de Terapia Intensiva Pediátrica/normas , Transplante de Fígado/métodos , Cuidados Pós-Operatórios/normas , Alprostadil/uso terapêutico , Infecções Bacterianas/classificação , Peso Corporal , Cardiotônicos/uso terapêutico , Dobutamina/uso terapêutico , Dopamina/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Lactente , Unidades de Terapia Intensiva Pediátrica/estatística & dados numéricos , Tempo de Internação , Transplante de Fígado/imunologia , Transplante de Fígado/normas , Omeprazol/uso terapêutico , Tamanho do Órgão , Complicações Pós-Operatórias/microbiologia
12.
Opt Express ; 18(6): 5541-55, 2010 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-20389570

RESUMO

The fastest ever 11.25Gb/s real-time FPGA-based optical orthogonal frequency division multiplexing (OOFDM) transceivers utilizing 64-QAM encoding/decoding and significantly improved variable power loading are experimentally demonstrated, for the first time, incorporating advanced functionalities of on-line performance monitoring, live system parameter optimization and channel estimation. Real-time end-to-end transmission of an 11.25Gb/s 64-QAM-encoded OOFDM signal with a high electrical spectral efficiency of 5.625bit/s/Hz over 25km of standard and MetroCor single-mode fibres is successfully achieved with respective power penalties of 0.3dB and -0.2dB at a BER of 1.0 x 10(-3) in a directly modulated DFB laser-based intensity modulation and direct detection system without in-line optical amplification and chromatic dispersion compensation. The impacts of variable power loading as well as electrical and optical components on the transmission performance of the demonstrated transceivers are experimentally explored in detail. In addition, numerical simulations also show that variable power loading is an extremely effective means of escalating system performance to its maximum potential.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Dispositivos Ópticos , Processamento de Sinais Assistido por Computador/instrumentação , Telecomunicações/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Micro-Ondas
13.
Opt Express ; 17(22): 19727-38, 2009 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-19997193

RESUMO

The fastest ever 6Gb/s real-time FPGA-based optical orthogonal frequency division multiplexing (OOFDM) transceivers utilizing channel estimation are experimentally demonstrated, for the first time, with variable power loading being incorporated to effectively compensate for the rapid system frequency response roll-off effect. The implemented transceivers are constructed entirely from off-the-shelf components and incorporate crucial functionalities of on-line performance monitoring and live optimization of key parameters including signal clipping, subcarrier power and operating conditions of directly modulated DFB lasers (DMLs). Real-time end-to-end transmission of a 6Gb/s 16-QAM-encoded OOFDM signal over 300m OM1 multi-mode fiber with a power penalty of 0.5dB is successfully achieved in an intensity-modulation and direct-detection system employing a DML.


Assuntos
Fibras Ópticas , Processamento de Sinais Assistido por Computador/instrumentação , Telecomunicações/instrumentação , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Micro-Ondas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Opt Express ; 17(22): 20484-93, 2009 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-19997277

RESUMO

The feasibility of implementing 128-QAM in off-the-shelf component-based real-time optical OFDM (OOFDM) transceivers incorporating advanced channel estimation, on-line performance monitoring and live parameter optimisation, is experimentally investigated, for the first time, in intensity-modulation and direct-detection (IMDD) single-mode fibre (SMF) and multi-mode fibre (MMF) transmission systems involving directly modulated DFB lasers. The highest ever spectral efficiency of 5.25bit/s/Hz is demonstrated successfully in the aforementioned simple systems. Experimental investigations show that, it is feasible to transmit 5.25 Gb/s 128-QAM-encoded OOFDM real-time signals over 25 km MetroCor(TM) SMFs and 500 m 62.5/125 microm OM1 MMFs. The impact of key parameters on the transmission performance of the real-time OOFDM transceivers with 128-QAM encoding are explored, based on which optimum signal clipping ratios are identified.


Assuntos
Lasers , Fibras Ópticas , Processamento de Sinais Assistido por Computador/instrumentação , Telecomunicações/instrumentação , Sistemas Computacionais , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Opt Express ; 17(19): 16654-65, 2009 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-19770881

RESUMO

Real-time optical orthogonal frequency-division multiplexing (OOFDM) transceivers based on off-the-shelf components including FPGAs are experimentally demonstrated, for the first time, incorporating key functionalities such as live transceiver optimisation and advanced channel estimation, and also utilising self-developed IFFT/FFT logic algorithms verified at 10 Gb/s. The fastest ever real-time end-to-end transmission of 3Gb/s DQPSK- and 16-QAM-encoded OOFDM signals over 500 m multi-mode fibers is achieved with BERs of <3.3x10(-9) in intensity-modulation and direct-detection systems employing directly modulated DFB lasers. Excellent performance robustness is also observed to various offset launch conditions. This work is a significant breakthrough in demonstrating the great potential of OOFDM for practical implementation in optical networks.

16.
Opt Express ; 17(17): 14574-85, 2009 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-19687937

RESUMO

Real-time optical orthogonal frequency division multiplexing (OOFDM) transceivers are experimentally demonstrated with advanced pilot subcarrier-assisted channel estimation being implemented. The channel estimation technique is, for the first time, proposed and experimentally verified rigorously, which offers a number of unique features including high accuracy, low complexity, small pilot bandwidth usage, excellent stability and buffer-free data flow. The fastest ever real-time end-to-end transmission of 3 Gb/s 16-QAM-encoded OOFDM signals over 75 km MetroCor single-mode fibres is achieved with negative power penalties of -2dB at BERs of 1.0 x 10(-4) in directly modulated DFB laser-based, intensity-modulation and direct-detection systems without in-line optical amplification and chromatic dispersion compensation.

17.
Opt Express ; 16(13): 9480-94, 2008 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-18575513

RESUMO

The impact of Adaptive Cyclic Prefix (ACP) on the transmission performance of Adaptively Modulated Optical OFDM (AMOOFDM) is explored thoroughly in directly modulated DFB laser-based, IMDD links involving Multimode Fibres (MMFs)/Single-Mode Fibres (SMFs). Three ACP mechanisms are identified, each of which can, depending upon the link properties, affect significantly the AMOOFDM transmission performance. In comparison with AMOOFDM having a fixed cyclic prefix duration of 25%, AMOOFDM with ACP can not only improve the transmission capacity by a factor of >2 (>1.3) for >1000 m MMFs (<80 km SMFs) with 1 dB link loss margin enhancement, but also relax considerably the requirement on the DFB bandwidth.


Assuntos
Algoritmos , Tecnologia de Fibra Óptica/instrumentação , Lasers , Modelos Teóricos , Processamento de Sinais Assistido por Computador/instrumentação , Telecomunicações/instrumentação , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de Radiação
19.
Zhongguo Zhong Yao Za Zhi ; 26(4): 226-32, 2001 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-12525044

RESUMO

OBJECTIVE: To develop and utilize the bee plants and bee products in Changbai Mountain area, the representative area of alpine plants in northeast China featuring abundant resources of bee plants. METHOD: The pollen of bee plants was observed and studied by LM and SEM. RESULT: The pollen is morphologically oblate, suboblate, spheroidal and prolate. The external sculpture is commonly reticulate, striate and echinulate. CONCLUSION: Plant pollen identification criteria have been furnished for the development of bee plant resources as well as the inspection of bee products in Changbai Mountain area.


Assuntos
Pólen/ultraestrutura , Animais , Abelhas , China , Mel , Microscopia Eletrônica de Varredura , Pólen/anatomia & histologia
20.
Zhongguo Yao Li Xue Bao ; 19(2): 136-40, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10374636

RESUMO

AIM: To study the relationship between the enhanced proliferation and renin-angiotensin system (RAS) of aortic smooth muscle cells (ASMC) from SHR rats. METHODS: To measure the effects of angiotensin II (Ang), captopril (Cap), saralasin (Sar) on proliferation, Ang and angiotensin converting enzyme (ACE) levels in cultured ASMC from WKY and SHR rats. RESULTS: Ang was a bifunctional growth factor, which induced SHR ASMC hyperplasia in 2% FCS-RPMI 1640 medium, but not in serum free (SF)-medium. SHR ASMC had stronger proliferative ability compared with WKY while SHR ASMC RAS was activated. Enhanced proliferation of SHR ASMC and ACE activity were obviously inhibited by long-term treatment (4-wk) of both Cap and Sar, while Ang content decreased in Cap treatment group and increased in Sar treatment group. The antiproliferative effect of Cap and Sar on SHR ASMC was stronger than that on WKY. SHR, WKY ASMC RAS were not influenced by short-term (24 h) treatment of Cap. CONCLUSION: Long-term treatment of Cap and Sar suppressed SHR ASMC growth through inhibition of Ang generation or blockade of Ang binding to its receptor.


Assuntos
Angiotensina II/farmacologia , Captopril/farmacologia , Hipertensão/patologia , Músculo Liso Vascular/patologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Angiotensina II/metabolismo , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Aorta/patologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultura Livres de Soro , Masculino , Peptidil Dipeptidase A/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Saralasina/farmacologia
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