Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Visible Human Projects”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 451 records · Page 25Linked to original sources
PubMed2003

[Dose reduction of radiographs of the pediatric pelvis for diagnosing hip dysplasia using a digital flat-panel detector system].

PURPOSE: To evaluate a possible dose reduction in pediatric pelvic radiographs in congenital hip dysplasia using a digital flat-panel system instead of a phosphor-storage system. MATERIALS AND METHODS: During a six-month period, all pediatric patients referred for pelvic radiography for the evaluation of congenital hip dysplasia were randomly assigned to be examined by either a phosphor-storage system or a digital flat-panel system, whereby the latter system was operated with half the radiation dose. Thirty pairs of radiographs were assessed for the visibility of 16 anatomic details and for 5 orthopedic-radiographic measurements (5-point scale with 1 = excellent; three independent observers). The projection indices of Ball and Kommenda and of Tönnis and Brunken were calculated for all radiographs. The Student's t-test was used to compare the flat-panel and the phosphor-storage radiographs for observers' assessments, patients' age and projection indices. RESULTS: In a total of 7560 observations, the scores for the visibility of anatomic details and orthopedic-radiographic measurements were respectively 2.72 and 2.64 for the flat-panel system and 2.93 and 2.79 for the phosphor-storage system. No significant differences were found between both systems (p > 0.05) and between patient age and projection indices (p > 0.05). CONCLUSION: Pediatric pelvic radiographs can be obtained with a digital flat-panel system using half the radiation dose instead of a phosphor-storage system without sacrificing relevant information in the diagnosis of congenital hip dysplasia.

Age Factors↗
PubMed1997

Improved vessel visualization in MR angiography by nonlinear anisotropic filtering.

This paper deals with a preprocessing technique of magnetic resonance angiography (MRA) images, applied before maximum-intensity-projection (MIP). The purpose was to recover small low-intensity vessels, visible in individual slices, but lost in MIP images that usually have higher background level than the individual slices. The authors have developed a nonlinear three-dimensional spatial filtering technique (called HD filter) based on anisotropic smoothing. The filter first searches for the local orientation of the vessel. It then performs a nonlinear smoothing in the vessel's local direction so as to avoid blurring its boundaries. Noise level reduction, contrast enhancement, and improved small vessel visibility achieved by this filter are illustrated on dynamic contrast-enhanced subtraction MRA images of the lower limbs.

Arteries↗
PubMed1998

3-Dimensional computerized tomography and virtual reality endoscopy of the reconstructed lower urinary tract.

PURPOSE: We describe postoperative surgical anatomy after orthotopic reconstruction of the lower urinary tract using 3-dimensional (D) computerized tomography (CT) and virtual reality endoscopy. MATERIALS AND METHODS: Electronic beam CT was performed in 39 men and 15 women a mean of 60 years old with an orthotopic ileal neobladder (50) or ureteroileal rectosigmoidostomy (4), followed by 3-D reconstruction of the pelvic anatomical structures using specialized computer hardware and software. The mean interval between surgery and CT was 15 months (range 3 to 110) and the mean interval between 2 subsequent 3-D CT studies in 22 patients was 6 months (range 3 to 9). RESULTS: CT time with the patient on the table was 45 minutes and computerized 3-D reconstruction time with the patient off the table was 4 to 5 hours. The pouch had a smooth ovoid shape in 66 and 82% of the patients on the first and second 3-D CT studies, respectively. Mean length of the antireflux nipple was 4 cm. (range 2.5 to 8) and mean length of the afferent limb was 6 cm. (range 3 to 15). There were no radiologically significant sex specific differences in the shape or dimensions of the urinary reservoirs, except for a tendency toward more acute angles between the pouch and remnant urethra. No pathological findings were visible on 3-D CT that were not also evident on conventional CT. CONCLUSIONS: Three-D CT may be clinically useful for surgical planning of a lower abdominal reoperation or unexplained findings and symptoms in patients with bladder substitutions. Cost and time expenditures for processing preclude its routine use in all cases. Virtual reality endoscopy may be a valuable tool for teaching and scientific purposes.

Adult↗
PubMed2002

Signals invisible to the collicular and magnocellular pathways can capture visual attention.

The retinal projection to the superior colliculus is thought to be important both for stimulus-driven eye movements and for the involuntary capture of attention. It has further been argued that eye-movement planning and attentional orienting share common neural mechanisms. Electrophysiological studies have shown that the superior colliculus receives no direct projections from short-wave-sensitive cones (S cones), and, consistent with this, we found that irrelevant peripheral stimuli visible only to S cones did not produce the saccadic distractor effect produced by luminance stimuli. However, when involuntary orienting was tested in a Posner cueing task, the same S-cone stimuli had normal attentional effects, in that they accelerated or delayed responses to subsequent targets. We conclude that involuntary attentional shifts do not require signals in the direct collicular pathway, or indeed the magnocellular pathway, as our S-cone stimuli were invisible to this channel also.

Attention↗
PubMed2006

Community nurses' health promotion work with older people.

AIMS: This paper reports a study describing community nurses' health promotion work with older people aged 50 years and above, and exploring particular health promotion initiatives for older people that would have transferability potential. BACKGROUND: With the ageing of populations worldwide, community nurses in primary healthcare settings have a key contribution to make to the health improvement agenda for older people, yet little is known of the extent of this aspect of their work. METHODS: Questionnaires were sent to 1062 community nurses in six Scottish National Health Service Boards - public health nurses/health visitors, district nurses, general practice nurses, community psychiatric and learning disability nurses and combined duty nurses; 373 (35%) responded, 30 of whom were interviewed by telephone. The data were collected in 2003-2004. FINDINGS: Findings confirmed the wide scope of health promotion, much of which may be embedded and unrecognized. Creative group work showed promise in achieving heath gain for older people, and a range of partnership approaches - interdisciplinary, multidisciplinary and interagency - was evident. Theoretical input and project opportunities within educational programmes had been a catalyst for health promotion initiatives in practice. However, evidence of audit, evaluation, and active involvement of older people in planning health promotion was limited. Funding of health promotion initiatives was vital to sustainability. CONCLUSION: There is merit in making the health promotion work of community nurses more visible through audit and systematic evaluation; promoting the active involvement of older people; strengthening partnership working; and further raising the profile of health in later life within undergraduate and postgraduate community nursing programmes.

Aged↗
PubMed2004

Confocal reflectance imaging of head and neck surgical specimens. A comparison with histologic analysis.

BACKGROUND: Confocal reflectance microscopy (CRM) is an optical method of imaging tissue noninvasively without the need for fixation, sectioning, and staining as in standard histopathologic analysis. Image contrast is determined by natural differences in refractive indices of organelles and other subcellular structures within the tissues. Gray-scale images are displayed in real time on a video monitor and represent horizontal (en face) optical sections through the tissue. We hypothesized that CRM is capable of discerning histologic characteristics of different tissues in the head and neck. OBJECTIVES: To examine the microscopic anatomy of freshly excised head and neck surgical specimens en bloc using CRM and to compare the findings with those generated by conventional histologic analysis. DESIGN: This was a pilot observational cohort study. Bone, muscle, nerve, thyroid, parotid, and ethmoid mucosa from human surgical specimens were imaged immediately after excision. Confocal images were compared with corresponding routine paraffin-embedded, hematoxylin-eosin-stained sections obtained from the same tissue. RESULTS: Characteristic histologic features of various tissues and cell types were readily discernible by CRM and correlated well with permanent sections. However, in all tissues examined, there was less microscopic detail visible in the CRM images than was appreciated in paraffin-embedded histologic sections. CONCLUSIONS: The CRM images revealed cytologic features without the artifacts of histologic processing and thus may have the potential for use as an adjunct to frozen-section analysis in intraoperative consultation.

Cohort Studies↗
PubMed2005

Reconstruction of optical properties of phantom and breast lesion in vivo from paraxial scanning data.

We report on the reconstruction of absorption and reduced scattering coefficients of breast tissue in vivo of a patient with mastopathic disease. Distributions of times of flight of photons through the compressed breast were recorded by paraxial scanning. From data measured at four different source-detector offsets optical properties were reconstructed within the linear Rytov approximation by a fast inverse Fourier space method. Low-pass filtering in Fourier space was employed to remove excessive noise from high spatial frequency components and to reduce the computational efforts by a factor of 3, typically. The mammograms displaying reconstructed absorption and reduced scattering coefficients were compared with projection mammograms either obtained by time-window analysis of experimental data or based on average absorption and reduced scattering coefficients which were derived from measured temporal point spread functions within a simple homogeneous model. All inhomogeneities which were visible in the projection mammograms and which could be associated with specific breast tissue compartments could be correlated with inhomogeneities in the reconstructed absorption coefficient. In particular, the mastopathic disease was detected in the reconstructed absorption mammogram. In order to assess reliability of optical properties reconstructed from data obtained by paraxial scanning, corresponding phantom experiments and reconstructions of phantom optical properties were carried out. Because of the limited angular range sampled by the in vivo and phantom measurements, considerable blurring of the absorption coefficient occurs along the compression direction, compromising longitudinal resolution.

Algorithms↗
PubMed2006

Development of real-time subcellular dynamic multicolor imaging of cancer-cell trafficking in live mice with a variable-magnification whole-mouse imaging system.

With the use of dual-color fluorescent cells and a highly sensitive whole-mouse imaging system with both macro-optics and micro-optics, we report here the development of subcellular real-time imaging of cancer cell trafficking in live mice. To observe cytoplasmic and nuclear dynamics in the living mouse, tumor cells were labeled in the nucleus with green fluorescent protein and with red fluorescent protein in the cytoplasm. Dual-color cancer cells were injected by a vascular route in an abdominal skin flap in nude mice. The mice were imaged with an Olympus OV100 whole-mouse imaging system with a sensitive CCD camera and five objective lenses, parcentered and parfocal, enabling imaging from macrocellular to subcellular. We observed the nuclear and cytoplasmic behavior of cancer cells in real time in blood vessels as they moved by various means or adhered to the vessel surface in the abdominal skin flap. During extravasation, real-time dual-color imaging showed that cytoplasmic processes of the cancer cells exited the vessels first, with nuclei following along the cytoplasmic projections. Both cytoplasm and nuclei underwent deformation during extravasation. Different cancer cell lines seemed to strongly vary in their ability to extravasate. With the dual-color cancer cells and the highly sensitive whole-mouse imaging system described here, the subcellular dynamics of cancer metastasis can now be observed in live mice in real time. This imaging technology will enable further understanding of the critical steps of metastasis and provide visible targets for antimetastasis drug development.

Animals↗
PubMedDate not supplied

Innovative approaches to reducing nurses' distractions during medication administration.

BACKGROUND: Contributing factors to medication errors include distractions, lack of focus, and failure to follow standard operating procedures. The nursing unit is vulnerable to a multitude of interruptions and distractions that affect the working memory and the ability to focus during critical times. Methods that prevent these environmental effects on nurses can help avert medication errors. METHODS: A process improvement study examined the effects of standard protocols and visible signage within a hospital setting. The project was patterned after another study using similar techniques. Rapid Cycle Testing was used as one of the strategies for this process improvement project. Rapid Cycle Tests have become a part of the newly adopted Define, Measure, Analyze, Improve, and Control steps at this particular hospital. RESULTS: As a result, a medication administration check-list improved focus and standardized practice. Visible signage also reduced nurses' distractions and improved focus. CONCLUSION: The results provide evidence that protocol checklists and signage can be used as reminders to reduce distractions, and are simple, inexpensive tools for medication safety.

Adult↗
PubMed2006

Low-dose megavoltage cone-beam computed tomography for lung tumors using a high-efficiency image receptor.

We report on the capabilities of a low-dose megavoltage cone-beam computed tomography (MV CBCT) system. The high-efficiency image receptor consists of a photodiode array coupled to a scintillator composed of individual CsI crystals. The CBCT system uses the 6 MV beam from a linear accelerator. A synchronization circuit allows us to limit the exposure to one beam pulse [0.028 monitor units (MU)] per projection image. 150-500 images (4.2-13.9 MU total) are collected during a one-minute scan and reconstructed using a filtered backprojection algorithm. Anthropomorphic and contrast phantoms are imaged and the contrast-to-noise ratio of the reconstruction is studied as a function of the number of projections and the error in the projection angles. The detector dose response is linear (R2 value 0.9989). A 2% electron density difference is discernible using 460 projection images and a total exposure of 13 MU (corresponding to a maximum absorbed dose of about 12 cGy in a patient). We present first patient images acquired with this system. Tumors in lung are clearly visible and skeletal anatomy is observed in sufficient detail to allow reproducible registration with the planning kV CT images. The MV CBCT system is shown to be capable of obtaining good quality three-dimensional reconstructions at relatively low dose and to be clinically usable for improving the accuracy of radiotherapy patient positioning.

Equipment Design↗
PubMed1983

Reduction of formation of denture plaque by a protease (Alcalase).

The efficacy of a protease preparation (Alcalase, Novo, Denmark) in preventing accumulation of plaque on the fitting surface of complete upper dentures was examined in a double-blind study. Seventeen denture wearers with clinically healthy oral mucosae participated in the study. The protease was dispensed in dissolvent tablets containing 15, 30, 60, 100, 300, 500, or 1000 mg of the enzyme. Enzyme tablets or placebo tablets were dissolved in 150 ml water at 50 degrees C, and the dentures were soaked once daily for 15 min. Denture soaking was performed with or without brushing. The study consisted of 14 1-week periods. At the start of each period the dentures were cleaned by brushing until they showed no visible plaque after staining. At the end of each period plaque was stained and the dentures were photographed. The photographs were projected, and the percentage area of the fitting surface showing plaque deposits was scored with 10% intervals. Statistical analysis showed that there was a significant reduction of plaque scores with increasing enzyme concentration. The most marked reduction in plaque formation was seen when mechanical cleansing was combined with immersion in a 500-mg enzyme solution. At a concentration of 300 mg (or more) the enzyme immersion was as efficient as mechanical cleansing in preventing denture plaque accumulation.

Dental Plaque↗
PubMedDate not supplied

National Rural Health Mission--"rhetoric or reality".

National Rural Health Mission (NRHM) launched by Government of India holds great hopes and promises to serve the deprived and underserved communities of rural areas. The backbone of the programme is Accredited Social Health Activist (ASHA), which will play major role in the implementation of the programme. The invariable existence of socio-cultural clusters in the community has always been a major challenge to the health care efforts made by the government. Though ASHA is a novel concept to melt the ice in the culture of silence among the various cluster community groups, it is important to emphasize that inter-cluster communication may still pose a problem, which ASHA may be unable to address. Considering the constraints of ASHA and success of cluster community approach in Unicef supported community based Maternal Child Health & Nutrition (MCHN) Project, it is quite reasonable to state that inclusion of community mobilisers (Bal Parivar Mitra) from within the cluster community group might well be an asset to the programme, who may actually bring about the task of spreading the spirit of NRHM. These set of functionaries may work in coordination to bring about the desired behaviour changes and decrease the social delays responsible for maternal and childhood mortality. It will also bring about the feeling of community participation and ownership. The programme is in its initial phase but has years ahead of it to bring visible changes at community level to make it a reality.

Child↗
PubMed1980

[Radiological study of painless knees in 50 men over 65 years of age. II. Axial projection and profile radiography (author's transl)].

Radiographs were taken in profile, and femoropatellar axial projection with 60 degrees flexion, in 50 men over 65 years of age who had never complained of symptoms related to their knees. Visible osteophytes of the patella are very frequently noted in profile radiography and were present in 35 subjects. Painless femoropatellar arthrosis is also frequent and this was noted on 60 degrees axial radiography in 7 subjects; unilaterally in 3 cases and bilaterally in 4 subjects. In 9 cases the femoropatellar arthrosis was external, while in 2 cases it was present both externally and internally. Detection of a patellar osteophyte on profile radiography does not necessarily imply the existence of femoropatellar arthrosis detectable radiologically on axial projection. This study was also able to define values for a certain number of the parameters of radiological morphology of the knee.

Aged↗
PubMed2000

The efficacy of surgically placed epidural catheters for analgesia after posterior spinal surgery.

Posterior spinal fusion for correction of scoliosis is a major procedure for which the provision of satisfactory, safe postoperative analgesia is often a problem. One possible solution involves the placement of epidural catheters under direct vision by the surgeon at the end of the procedure, followed by an epidural infusion of local anaesthetic with or without an opioid. Despite its simplicity, this technique has not been reported as being consistently successful. We report an observational study of the analgesia achieved with surgically placed epidural catheters and of the reasons for the failure of the technique. Fourteen consecutive patients undergoing posterior spinal fusion had epidural catheters placed by the surgeon and had radio-opaque dye injected down the catheter 15 min before their routine postoperative chest X-ray. Analgesia was assessed at 0, 6, 12 and 24 h after surgery using visual analogue scores. Five patients had inadequate pain control; none of these patients had dye visible in the epidural space. Seven patients had dye visible in the epidural space; all of these cases had satisfactory analgesia. In two cases, dye was observed in the paravertebral gutters; both of these patients had satisfactory postoperative analgesia. This small pilot study suggests that correctly placed 'surgical' epidural catheters are capable of providing good analgesia after posterior spinal fusion and that misplaced catheters, seen in a large proportion of patients, are associated with inadequate analgesia.

Adolescent↗
PubMed2007

[Visual rating of T2'-blood-oxygen-level-dependent magnetic resonance imaging in acute stroke patients--a pilot study].

PURPOSE: Delineation of brain tissue that is at risk but not yet infarcted (penumbra) continues to be a major challenge for stroke imaging. Metabolic characterization of the penumbra might be able to be achieved using blood-oxygen-level-dependent (BOLD) imaging. MATERIALS AND METHODS: We analyzed MRI data from 20 patients within the first 6 hours after stroke onset and after 5-8 days. Among other sequences, the MRI protocol consisted of diffusion-weighted (DWI/ADC = apparent diffusion coefficient) and quantitative T2 and T2* imaging (qT2, qT2*). BOLD images (T2') were calculated using 1/T2' = 1/qT2* - 1/qT2. BOLD lesions were rated by two blinded observers. RESULTS: Based on the primary blinded reading of the BOLD images, the lesion side was rated correctly by observers 1 and 2 in 80/50 % of the cases, incorrectly in 5/40 % of the cases, and rated as not visible in 15/10 % of the cases. After unblinding the observers, the visibility was rated in 45/45 % of the cases as good, in 35/40 % of the cases as reasonable, and in 20/15 % of the cases as insufficient for diagnostic purposes. The sensitivity for subsequent infarct growth was 0.88 (95 % confidence interval, CI 0.47 to 0.99), the specificity was 0.33 (95 % CI 0.07 to 0.70), the positive predictive value (PPV) was 0.54 (95 % CI 0.25 to 0.81), and the negative predictive value (NPV) was 0.75 (95 % CI 0.19 to 0.99). The odds ratio for subsequent infarct growth was 3.5 (95 % CI 0.20 to 115.53). CONCLUSION: Hypo-intense lesions in BOLD imaging were visible and exceeded the lesion in diffusion-weighted imaging in most of the stroke patients. The encouraging results justify further testing of the hypothesis that BOLD lesions, when larger than DWI lesions, are associated with infarct growth from initial DWI to final infarct.

Acute Disease↗
PubMed1998

Treatment of pigment epithelial detachments due to age-related macular degeneration with intra-ocular C3F8 injection.

PURPOSE: To flatten pigment epithelial detachments (PED) due to age-related macular degeneration in an attempt to visualize the underlying choroidal neovascularization by fluorescein angiography (FA) and reveal a treatment target. METHODS: Nine patients with PED received intravitreal gas injections via the pars plana and postured face down. Fluorescein angiograms were obtained before and after gas injection. In two patients, retinal scotopic sensitivity was also measured. RESULTS: Eight patients demonstrated change in the shape and size of the PED following gas injection. Four patients showed a better delineation of underlying structures on FA. Three patients had focal laser treatment to the newly visible choroidal neovascular complex, but this was successful in only one patient with flattening of the PED. CONCLUSION: Pigment epithelial detachments can be modified by intravitreal gas injection in some patients, but this treatment did not have a major impact on overall outcome or management.

Aged↗
PubMed1996

A pilot study comparing toluidine blue and hematoxylin and eosin staining of basal cell and squamous cell carcinoma during Mohs surgery.

BACKGROUND: Hematoxylin and Eosin (H&E) is the most common stain used for Mohs frozen sections. Toluidine blue (T-blue) is a metachromatic stain that has been frequently utilized for this purpose. OBJECTIVE: To compare the cytologic and stromal staining patterns of each stain for Mohs frozen sections of squamous cell carcinoma (SCC) and basal cell carcinoma (BCC), and to identify the advantages and disadvantages of each technique. RESULTS: T-blue revealed stromal change associated with the presence of BCC and SCC. H&E provided more prominent visibility of individual cell keratinization and necrosis, which are common features seen in SCC. CONCLUSION: We found T-blue to be fast and effective in identifying mucopolysaccharides in stroma associated with basal cell carcinoma. For this reason, T-blue is our preferred stain for BCCs, while H&E can provide greater ease of identification of histologic features of SCCs.

Basal Cell Carcinoma↗
PubMedDate not supplied

Vessel enhancement filtering in three-dimensional MR angiograms using long-range signal correlation.

Small vessels in three-dimensional MR angiograms have low visibility in maximum-intensity projection images because of their low contrast. In a previous study, we had two nonlinear filters that appeared to give significant improvement in small vessel detail. In this paper, we report on a generalization of this filter that allows a more general modeling of the vessels and a more complete suppression of background. One implementation of the general filter gave a vessel mean contrast-to-noise ratio that is 2.52 and 3.51 times higher than the vessel mean contrast-to-noise ratio obtained using our previously reported maximum-minimum (max-min) filter and cross-section filter, respectively.

Blood Vessels↗