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1.
Appl Opt ; 54(30): 8835-43, 2015 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-26560368

RESUMO

We describe the design, development, and performance of a narrowband, all-reflective, unaliased spatial heterodyne spectrometer (SHS) that has been tested in observations at the focus of the 1.6 m main telescope of the McMath-Pierce solar telescope on Kitt Peak. The all-reflective SHS described herein is a highly robust common-path Fourier transform spectrometer without moving parts that, over a limited spectral region, combines the large field of view and high resolving power characteristic of interference spectrometers but at substantially reduced instrument size and optical tolerances. The self-scanned region of wavelength space and resolving power of the SHS are determined by the beam size, the diffraction grating groove density, the number of detector elements, and the fixed orientation of a set of pilot mirrors. The results presented here represent the first successful implementation of this reflective SHS design for field use. We discuss concepts behind the unaliased reflective SHS design and report the performance of the instrument when used to observe terrestrial airglow and absorption features, the solar spectrum, and the Jovian spectrum near λ=6300 Å, at the achieved resolving power (R=λ/δλ) of R>100,000. The results confirm that reflective SHS instruments can deliver effective interferometric performance in the visible to the far-ultraviolet wavelengths with commercial optics of moderate surface quality.

4.
Heart Lung ; 28(6): 429-37, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10580217

RESUMO

PURPOSES: To investigate symptom experiences of patients who have single and bilateral-sequential lung transplantation and to determine whether differences exist according to gender, pretransplantation diagnosis, and type of transplantation procedure. DESIGN AND METHODS: In the context of a descriptive, comparative survey design, surviving recipients of single and bilateral-sequential lung transplants (n = 56) were mailed a symptom frequency and distress questionnaire. The response rate was 85.7% (n = 48). The average time since the recipients' lung transplantations was 1.5 +/- 0.7 years. RESULTS: Recipients of lung transplants reported that several symptoms (eg, muscle weakness, shortness of breath with activity, and changed appearance) were both frequently occurring and quite distressing. Other symptoms were identified as being distressing, but not frequently occurring, or vice versa. Significant (P <.05) differences were found for symptom experiences among pretransplant diagnostic groups and between genders and types of transplant procedures. CONCLUSIONS: These findings elucidate the symptom experiences of recipients of lung transplants and suggest that subgroup differences exist. The data provide a basis for strengthening patient and family education and for developing symptom management strategies. Further investigation of the symptom experiences of the recipients of lung transplants is needed, especially in relation to subgroups.


Assuntos
Transplante de Pulmão , Estudos de Casos e Controles , Fibrose Cística/cirurgia , Feminino , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Pneumopatias/cirurgia , Pneumopatias Obstrutivas/cirurgia , Transplante de Pulmão/efeitos adversos , Transplante de Pulmão/psicologia , Transplante de Pulmão/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Fatores Sexuais
6.
Protist ; 149(3): 277-90, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23194639
7.
Protist ; 149(1): 3-6, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23196106
8.
Protist ; 149(1): 89-97, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23196116
9.
J Ambul Care Manage ; 17(3): 76-80, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10136097

RESUMO

Failed patient appointments in ambulatory care may result in decreased revenues. The purpose of this study was to determine if patient reminders would affect the "no-show" rate of a medical ambulatory care setting. Patients of 10 physicians participated in a 6-week study. Patients were randomly assigned to one of three groups: 2 weeks of appointment reminder postcards, 2 weeks of appointment reminder phone calls, and 2 weeks of no intervention. Chi-square analysis revealed significant differences between the control group and the two groups receiving interventions. Patient reminders may be a mechanism to decrease the no-show rate in ambulatory care.


Assuntos
Agendamento de Consultas , Ambulatório Hospitalar/organização & administração , Cooperação do Paciente , Sistemas de Alerta/normas , Centros Médicos Acadêmicos/organização & administração , Centros Médicos Acadêmicos/estatística & dados numéricos , Distribuição de Qui-Quadrado , Coleta de Dados , Pesquisa sobre Serviços de Saúde/métodos , Relações Hospital-Paciente , Humanos , Illinois , Medicina/organização & administração , Ambulatório Hospitalar/estatística & dados numéricos , Serviços Postais/estatística & dados numéricos , Distribuição Aleatória , Especialização , Telefone/estatística & dados numéricos
15.
Biosystems ; 28(1-3): 1-14, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1292654

RESUMO

The present Botanical and Zoological Codes of Nomenclature are often inadequate for resolution of all the peculiar problems caused by the very nature of the numerous and diverse groups of the so-called 'lower' eukaryotic organisms known as protists. Whether or not a separate code should therefore be created for these species--many but not all of which are unicellular in structure and microscopic in size--is complicated by several factors. The principal one is related to the wide dispersal of protists throughout many taxonomic classes and phyla/divisions; sometimes even multiple kingdoms are involved. If recognition of a single kingdom Protista is no longer tenable, then even the concept of one code per kingdom is not applicable. Other difficulties arise primarily from long-standing differences in major provisions of present Botanical and Zoological Codes. Numerous 'ambiregnal' forms exist, species currently under dual code jurisdiction. The matter of names for suprafamilial taxa of protists, irrespective of their ultimate kingdom assignment, poses another set of concerns not yet resolved. A plea is made to recognize the legitimacy of having distinct high-level ranks for protist species that seem to be widely separated phylogenetically from fellow protists or from other eukaryotic assemblages.


Assuntos
Eucariotos/classificação , Animais , Classificação , Células Eucarióticas , Filogenia , Terminologia como Assunto
16.
J Heart Transplant ; 9(2): 92-6, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2181091

RESUMO

Factors that predict hospital length of stay after heart transplantation were identified from retrospective data of 65 patients (82% male, mean age, 43.3 years). Multiple regression analysis with a stepwise procedure was used to generate three predictive models for length of stay: (1) a model to be used before operation, (2) a model that combines preoperative and donor information, and (3) a model that takes preoperative, donor, and postoperative factors (complete model) into consideration. Hospital length of stay ranged from 15 to 45 days after heart transplantation (median length of stay, 22.5 days; mean length of stay, 24.4 +/- 6.4 days). In the preoperative model, diagnosis, duration of cardiac symptoms, severity of heart failure, and pulmonary vascular resistance were significantly related to length of stay and together accounted for 36% of the variance in length of stay. When donor information (for example, size and ischemic time) was added to preoperative information, the resultant model failed to account for appreciably more of the variance in length of stay. A model that considered preoperative, donor, and postoperative factors accounted for 71% of the variance in length of stay. Significant variables in the model were the month in which the patient had transplantation in the program, duration of cardiac symptoms before transplantation, preoperative severity of heart failure, pulmonary vascular resistance, and postoperative incidence of severe acute rejection. Patient age, sex, and postoperative infections were not related to length of stay. In conclusion, there are cardiopulmonary and immunologic factors that can predict length of stay. The model also suggests that a program's experience with heart transplantation affects length of stay.


Assuntos
Transplante de Coração , Tempo de Internação/estatística & dados numéricos , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Análise de Regressão
19.
Pediatr Res ; 27(1): 89-97, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2136947

RESUMO

The metabolism of individual dietary n-3 fatty acids was studied in n-3 fatty acid-deficient newly hatched chicks. Laying hens were fed the n-6 fatty acid, ethyl linoleate, as the only source of polyunsaturated fat. Chicks were then fed the n-3-deficient hens' diet, or one of three other diets supplemented with the ethyl ester of 18:3 n-3, 20:5 n-3 [eicosapentaenoic acid (EPA)], or 22:6 n-3 [docosahexaenoic acid (DHA)] at 0.44% of calories. At the end of 0, 1, 2, and 3 wk, the fatty acid composition of the brain, retina, liver, and serum was determined. Dietary EPA and DHA were equally effective at raising levels of DHA in the brain and retina. Dietary 18:3 was relatively ineffective in restoring brain and retina DHA. In the n-3-deficient chicks fed EPA or DHA, levels of DHA recovered to control values in both the brain and retina by 3 wk. Very little EPA accumulated in the brain or retina of chicks fed EPA. Hepatic synthesis of DHA from EPA appeared low, suggesting that the brain and retina synthesized the DHA that accumulated rapidly in these tissues after the feeding of EPA. The delta-4-desaturase enzyme was apparently very active, then, in the brain and retina. Retroconversion of dietary 22:6 to 22:5 and 20:5 was evident in the serum, liver, and retina but not in the brain. Thus, it was possible to study the relative metabolism and especially the interconversion of n-3 fatty acids in a environment uncomplicated by existing stores of these essential fatty acids. This study would suggest that 18:3 as the sole source of n-3 fatty acids in the diets of animals, including the human infant, may not be adequate for the biochemical development of the brain and retina and that dietary DHA is the preferred fatty acid of the n-3 series.


Assuntos
Encéfalo/crescimento & desenvolvimento , Galinhas/crescimento & desenvolvimento , Gorduras Insaturadas na Dieta/metabolismo , Ácidos Docosa-Hexaenoicos/metabolismo , Retina/crescimento & desenvolvimento , Animais , Encéfalo/metabolismo , Química Encefálica , Ácidos Docosa-Hexaenoicos/análise , Ácidos Docosa-Hexaenoicos/sangue , Ácidos Graxos/análise , Ácidos Graxos/sangue , Retina/análise , Retina/metabolismo
20.
Eur J Protistol ; 26(1): 15-24, 1990 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-23196121

RESUMO

Most of the so-called "lower hypostomes", nassophorean ciliates in the most recent classifications of the phylum Ciliophora, have been little studied in modern times (e.g., employing methods of silver impregnation, a technique widely considered indispensable in comparative taxonomic work on these protists today). In this paper, we present descriptions of two species, a new strain of Nassulopsis elegans (Ehr., 1833) and Zosterodasys derouxi n.sp., based primarily on use of the pyridinated silver carbonate method of Fernández-Galiano. From our own data, especially on the oral hypostomial frange of the first organism and the true somatic synhymenium of the second, and review of the relevant literature, we suggest that the phylogenetic affinities of these forms need to be reassessed. We also tentatively propose some changes in the suprafamilial classification of the ciliate groups involved. While recognizing the need for additional information that can be supplied only by future ultrastructural studies and comparative morphogenetic investigations, we briefly offer the following two speculative ideas at this time: (1) that Nassulopsis be removed from the order Synhymeniida and be considered an evolutionarily primitive genus of the "higher" order Nassulida; and (2) that Zosterodasys be considered a "pivotal" primitive nassophorean that may have given rise, phylogenetically, not only to the more evolved groups of its own class (the Nassophorea) but also to the (primitive groups of the) entire neighboring class Phyllopharyngea.

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