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3.
Cryo Letters ; 35(3): 162-70, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24997833

RESUMO

BACKGROUND: The pan-tropical genus Ardisia has more than 400 species and is of high horticultural and medicinal value. Due to overexploitation it is important to conserve the germplasm of this genus. OBJECTIVE: To investigate the feasibility and methods of cryopreservation for long-term seed storage of three Ardisia species: A. elliptica Thunb., A. brunnescens Walker, and A. virens Kurz. METHODS: We tested whether rapid desiccation can increase desiccation tolerance and cryotolerance, and whether the thawing rate can affect cryopreservation success. Seeds were subjected to three desiccation treatments: 1) activated silica gel at 25 +/- 2 degree C, and 4% relative humidity (RH); 2) saturated NaCl solution in closed jars in 25 +/- 2 degree C and 75% RH; and 3) air-drying at room conditions at 27 +/- 2 degree C and RH 60% for different desiccation durations (12h, 24h, 48h, 96h, and 196h). Seeds were then assessed for desiccation tolerance and cryotolerance after rapid thawing (direct immersion in 36 degree C water bath for 2 min) or slow thawing (at 27°C for 1 h). RESULTS: For all three species, desiccation method and duration significantly affected cryotolerance (P < 0.0001). Fast desiccation did not improve germination compared to slower desiccation (P < 0.01). Whereas A. elliptica germination was unaffected by desiccation duration, drying time significantly (P < 0.0001) affected germination percentage in the other two species especially after 48h. Although slow thawing improved cryotolerance of A. brunnescens seeds (P < 0.05), there was no significant effect of thawing rate on A. elliptica. A. virens seed did not survive cryopreservation. CONCLUSIONS: Cryopreservation protocols of Ardisia species may be species-specific and should be established for each species in the genus so that cryopreservation can be used as a successful conservation strategy.


Assuntos
Ardisia/crescimento & desenvolvimento , Criopreservação/métodos , Dessecação/métodos , Sementes/crescimento & desenvolvimento , Germinação , Umidade , Sílica Gel/química , Água/química
4.
Int J Tuberc Lung Dis ; 3(12): 1137-9, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10599020

RESUMO

OBJECTIVE: To evaluate the utility of sputum induction in the large-scale tuberculosis control program. METHODS: Prospective study on sputum induction for improving the diagnostic yield of pulmonary tuberculosis, and estimation of the direct costs for sputum induction. RESULTS: Of 1,648 tuberculosis suspects with poor or absent sputum production, induced sputum was smear-positive in 558 patients (353 previously smear-negative, 97 inadequate sputum and 108 unproductive). The direct cost per induced sputum was US $0.37. CONCLUSION: Sputum induction is an effective, low-cost, and simple technique for improving the smear-positive case detection rate in a tuberculosis control program.


Assuntos
Mycobacterium tuberculosis/isolamento & purificação , Escarro/microbiologia , Tuberculose Pulmonar/prevenção & controle , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Custos e Análise de Custo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Manejo de Espécimes/economia , Tuberculose Pulmonar/economia
5.
Space Med Med Eng (Beijing) ; 12(6): 431-5, 1999 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-12434810

RESUMO

Objective. To probe into the characteristics of authors, institutes and region distribution of papers published in "Space Medicine & Medical Engineering" (SMME), as well as its papers indexed and cited by CBMDisc, CB-ISITC and CSCD-CD98; to look into its core authors, core regions and core institutes. Method. Bibliometric method was used to analyse its published papers, cited papers and indexed papers. Result. 716 papers have been published in SMME, among which 622 were coauthor papers (86.9%); 94 were single author papers (13.1%); organization collaboration papers 109 (15.2%); institutes 548 (76.5%); colleges and Universities 132 (18.4%); hospitals 36 (5.1%). CBMDisc and CB-ISTIC index rate were 81% and 75% of its papers respectively, SMME's 39 papers were cited in 25 journals via CSCD-CD98, 10 of 42 core authors are cited. Conclusion. Papers published in SMME per issue have been increasing in 10 years, core region is Beijing. Core authors have been formed in SMME. Papers indexed by CBMDisc and CB-ISTIC are also increasing. But its citation status is not ideal, and high cited papers and high cited authors are few. Numbers and types of Natural Scientific Foundation supported papers are increasing.


Assuntos
Medicina Aeroespacial , Autoria , Bibliometria , Publicações Periódicas como Assunto , Editoração , Academias e Institutos , China , Análise Multivariada , Estudos Retrospectivos
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