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Biomedical subjects

D Francis

Publications and source records attributed to D Francis.

At least 181 records · Page 10Linked to original sources
PubMed1971

Direct test of the positive pressure gradient theory of pseudopod extension and retraction in amoebae.

When one pseudopod of an amoeba is sucked into a capillary connected to a partial vacuum and subjected to a pressure reduction of 30 to 35 centimeters of water, extension of other pseudopods, exposed to atmospheric pressure, is not prevented. This result is interpreted to mean that cytoplasmic streaming cannot be the result of a positive pressure gradient generated along the length of the stream, for if it were, streaming would have reversed its direction under the applied pressure gradient of opposite sign and supposedly greater magnitude.

Amoeba↗
PubMedDate not supplied

Peroperative fine-needle aspiration biopsy: an aid to differential diagnosis between diverticular disease and colonic cancer? A preliminary report.

Fine-needle aspiration biopsy was performed at laparotomy on 15 patients in whose cases differential diagnosis between colonic diverticulitis and colonic cancer on the basis of preoperative and peroperative examinations was impossible. Histologic examination confirmed the cytologic diagnosis to be correct in 14 cases, in four of them correctly positive for tumor cells. There was one false-negative result. Culture of swabs taken from 11 patients after puncture showed growth of intestinal bacteria in five cases, but no complication developed in association with or after the punctures. Peroperative fine-needle aspiration biopsy is a cheap, simple, rapid and safe method that seems to offer a reliable aid to differential diagnosis between diverticulitis and carcinoma. With the use of a rapid staining technique, the result can be available as early as that of frozen-section microscopic examination.

Adult↗
PubMedDate not supplied

Evaluation of a real-time passive personal particle monitor in fixed site residential indoor and ambient measurements.

Recent experimental findings in animals and humans indicate adverse respiratory effects from short-term exposures to particulate air pollutants, especially in sensitive subpopulations such as asthmatics. The relationship between air pollution and asthma has mainly been determined using particulate matter (PM) measurements from central sites. Validated tools are needed to assess exposures most relevant to health effects. Recently, a personal passive particulate sampler (personal Data-RAM, pDR, MIE Inc., Bedford, MA) has become available for studying personal exposures to PM with time resolution at 1 min. The pDR measures light scatter from PM in the 0.1-10 microM range, the significant range for health effects. In order to assess the ability of the pDR in predicting gravimetric mass, pDRs were collocated with PM2.5 and PM10 Harvard Impactors (HI) inside and outside nine homes of asthmatic children and at an outdoor central Air Pollution Control District site. Results are presented of comparisons between the HI samplers and the pDR in various modes of operation: passive, active, and active with a heated inlet. When used outdoors at fixed sites the pDR readings exhibit interference from high relative humidity (RH) unless operated with a method for drying inlet air such as a heater, or if readings at times of high RH are adjusted. The pDR correlates more highly with the HI PM2.5 than with the HI PM10 (r2 = 0.66 vs. 0.13 for outdoors, r2 = 0.42 vs. 0.20 for indoors). The pDR appears to be a useful tool for an epidemiologic study that aims to examine the relationship between health outcomes and personal exposure to peaks in PM.

Adolescent↗
PubMedDate not supplied

Progress in preoperative diagnosis of pulmonary lesions.

Forty consecutive patients with radiologically demonstrated pulmonary lesions were selected according to the following criteria: 1) no cytologic or histopathologic diagnosis performed by conventional examination methods, and 2) no tumor tissue seen by endoscopy including the flexible bronchoscope. In these 40 patients the diagnostic value of speciments obtained by transthoracic fine-needle aspiration by blind bronchial brushing and by biopsy taken by means of the flexible bronchoscope was compared with these diagnostic methods a preoperative correct diagnosis was obtained in 29 (72.5%) cases. In 17 cases (42.5%) the fine-needle aspiration method was the only way to obtain a correct preoperative diagnosis and in four cases (10%) the diagnosis was obtained by the fiberscope.

Aged↗
PubMedDate not supplied

Reflective writing: a strategy to foster critical inquiry in undergraduate nursing students.

Whilst nursing has recognised the importance of reflective practitioners, few strategies designed to achieve this outcome are currently apparent in nursing education literature. Writing, forwarded as one way to enhance the development of critical thinking and reflection in undergraduate nursing students, is the focus of this article. The article describes a project undertaken to explore the ways writing could be incorporated into an undergraduate curriculum as a strategy to enhance and extend personal and professional meaning-making. It examines a number of strategies utilised in the project and offers some insightful understandings developed by the team.

Curriculum↗
PubMedDate not supplied

Moving from technical to critical reflection in journalling: an investigation of students' ability to incorporate three levels of reflective writing.

This paper outlines a research project aimed at changing the levels of reflection of preregistration nursing students in a tertiary institution. Whilst reflection is widely espoused now in nursing, few studies have been found that identify whether the level of reflective writing can be identified or developed by students. Anecdotal and research evidence (Powell 1989; van Manen 1977) however indicates that most student reflective writing occurs at the technical level. A descriptive exploratory study using both qualitative and quantitative techniques was undertaken to apply van Manen's (1977) levels in a structured way in an attempt to facilitate the student's understanding and use of the levels in their reflective writing. The findings of the study indicate that student self evaluation and identification of the levels in their own writing can lead to change in the levels of critical reflective writing achieved by undergraduate students.

Adult↗