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PubMed1980

Kidney size in normal children measured by sonography.

Kidney length and depth were measured by sonography in 46 normal children fro 0 to 16 years of age. Sonography was used to obtain kidney measurements without the known magnification caused by factors of chemical and photographic nature seen by urography. The results of our study were used to control the age-adapted equipment for renography in children. There was a good correlation between kidney length and depth and variables like age, weight, height and body surface area. The best values were found in the correlations to body surface area. We could confirm the previous findings by other methods of kidney size measurements in children that there is no significant difference in kidney length between boys and girls. The left kidney is slightly longer than the right one and the kidney centre distance is slightly but significantly larger on the left side. No such difference was present in the distance skin to kidney surface.

Adolescent↗
PubMed2000

The relationship between frequency of rapid eye movements in REM sleep and SWS rebound.

Previous studies have shown a decrease in rapid eye movement (REM) frequency during desynchronized sleep in recovery nights following total or partial sleep deprivation. This effect has been ascribed to an increase in sleep need or sleep depth consequent to sleep length manipulations. The aims of this study were to assess REM frequency variations in the recovery night after two consecutive nights of selective slow-wave sleep (SWS) deprivation, and to evaluate the relationships between REM frequency and SWS amount and auditory arousal thresholds (AAT), as an independent index of sleep depth. Ten normal males slept for six consecutive nights in the laboratory: one adaptation, two baseline, two selective SWS deprivation and one recovery night. SWS deprivation allowed us to set the SWS amount during both deprivation nights close to zero, without any shortening of total sleep time. In the ensuing recovery night a significant SWS rebound was found, accompanied by an increase in AAT. In addition, REM frequency decreased significantly compared with baseline. This effect cannot be attributed to a variation in prior sleep duration, since there was no sleep loss during the selective SWS deprivation nights. Stepwise regression also showed that the decrease in REM frequency is not correlated with the increase in AAT, the traditional index of sleep depth, but is correlated with SWS rebound.

Adult↗
PubMedDate not supplied

Factors predictive of survival in patients with node-positive colorectal cancer in Taiwan.

BACKGROUND/AIMS: Preoperative CEA levels, depth of tumor penetration, and the number of positive lymph nodes were reported as independent factors prognostic of survival in colorectal cancer patients. This study was carried out in an effort to evaluate the prognostic significance of these three factors in patients with Dukes' C colorectal cancer in Taiwan. METHODOLOGY: Between 1992 and 1994, a total of 112 patients with node-positive colorectal cancer were evaluated retrospectively at the Veteran General Hospital-Taipei. All patients underwent potentially curative surgery and received 5-fluorouracil based adjuvant chemotherapy. Reference to the Dukes' classification was according to the classical criteria described in 1932 for carcinoma of the rectum and adapted for use in colonic tumors. Data on the location of the tumor, depth of penetration, number of positive lymph nodes, degree of tumor differentiation, and preoperative CEA levels were analyzed to understand their association with survival. Blood samples for CEA measurement were taken a few days before operation. A multivariate analysis using the Cox's proportional hazards regression model was then performed to determine the most important independent predictors of survival among all the possible variables. RESULTS: Using univariate analysis the number of positive lymph nodes (P < 0.001), penetration of the bowel wall (P < 0.001), and preoperative CEA levels (P < 0.001) were found as significant prognostic factors, while the degree of tumor differentiation, location of the tumor, age and sex were not significant. Using multivariate Cox analysis the number of positive lymph nodes, penetration of the bowel wall, and preoperative CEA levels were still found as independent prognostic factors in node-positive colorectal cancer patients. CONCLUSIONS: Data obtained from our study indicates that preoperative CEA levels, depth of tumor penetration, and the number of positive lymph nodes were independent prognostic factors in Dukes' C colorectal cancer patients. They could serve as appropriate modifications of the initial Dukes scheme in node-positive diseases.

Carcinoembryonic Antigen↗
PubMed2000

Periodontal tissue responses after insertion of artificial crowns and fixed partial dentures.

PURPOSE: The purpose of this review was, first, to critically evaluate published evidence on the effects of artificial crowns and fixed partial dentures (FPDs) on adjacent periodontal tissue health, and second to synthesize this evidence into meaningful summaries. Restoration qualities that contribute to inflammatory responses were identified based on strength of evidence, and variables that should be controlled in future investigations were outlined. Such information is necessary to accurately predict the prognosis of periodontal tissues adjacent to crowns or FPDs. METHODS: Clinical trial and epidemiologic evidence published in English was collected. The effects of crowns or FPDs on gingival inflammation, probing depths, and bone loss were evaluated based on accuracy of measurement, reliability of measurement, and/or appropriateness of data analysis. RESULTS: Crowns and FPDs increased the incidence of advanced gingival inflammation adjacent to restorations, particularly if restorations had intracrevicular finish line placement, poor marginal adaptation, or rough surfaces. However, because of the limitation in the accuracy and reliability of probing depth measurements, reports of greater mean probing depths of crowned teeth, which tended to be less than 1 mm greater than control teeth, should be questioned. Finally, crowns and FPDs in general did not accelerate the rate of adjacent bone loss. CONCLUSION: Clinically deficient restorations, as well as clinically acceptable restorations, can contribute to gingival inflammation. However, with the limitations of the applied methods of measurement, current evidence has not shown an increased attachment loss adjacent to crowns or FPDs. Future trials should document periodontal health before therapy and periodically after restoration insertion so that each tooth serves as its own control. In future studies, the periodontal disease history of the patient, the influence of the restoration on plaque formation, and the composition of the crevicular microflora must be recorded.

Alveolar Bone Loss↗
PubMed1995

Natural problems for stereoscopic depth perception in virtual environments.

The use of virtual reality (VR) display systems has escalated over the last 5 yr and may have consequences for those working within vision research. This paper provides a brief review of the literature pertaining to the representation of depth in stereoscopic VR displays. Specific attention is paid to the response of the accommodation system with its cross-links to vergence eye movements, and to the spatial errors that arise when portraying three-dimensional space on a two-dimensional window. It is suggested that these factors prevent large depth intervals of three-dimensional visual space being rendered with integrity through dual two-dimensional arrays.

Accommodation, Ocular↗
PubMed1994

The interaction of depth parameters in motion integration with polar plaids.

Many parameters have been investigated as to their effect on the way in which the visual system is able to integrate different motion directions at the same visual location. Of special interest have been parameters that determine the depth relationship between surfaces, such as disparity, relative contrast, and occlusion versus transparency. The preferred stimulus for this research has been the 'plaid', usually constructed from two linear gratings. The present study concentrated not on these Cartesian plaids, but on polar plaids, made from a combination of concentric circles and radial gratings. These kinds of plaids also have a special theoretical significance: within the Lie Transformation Group approach to visual pattern processing, Cartesian and polar stimuli represent different invariances in the visual world. This study compared Cartesian, polar and hybrid plaids as to their propensity to be perceived as coherently moving stimuli. Cartesian and polar plaids were similar in terms of the effects of intersection luminance and relative contrast on coherence, polar plaids being consistently less coherent. Hybrid plaids did not usually cohere at all. Adaptation to an unambiguously coherent plaid decreased perceived coherence when tested with a bistable plaid from the same, and not from the other Lie group, i.e. there was within-group adaptation but no between-group adaptation. Polar plaids also offer the possibility of studying the influence of another depth parameter on motion integration: expansion or contraction of circular gratings, which represent motion-in-depth toward or away from the observer. This motion-in-depth was tested for interaction with disparity or relative contrast in the determination of motion integration. The results were negative under the present conditions. Thus not all depth parameters contribute equally to the determination of the stimulus depth relations affecting the motion integration process.

Depth Perception↗
PubMed2005

Irradiance regulation of photosynthesis and respiration in modern marine microbialites built by benthic cyanobacteria in a tropical lagoon (New Caledonia).

Microbialites are organosedimentary deposits that have built up as a result of the growth and binding of detrital sediment by a benthic microbial community. This study focuses on microbialites built by monospecific populations of cyanobacteria in the south-west lagoon of New Caledonia, where they have been observed down to 20-25 m depth. The aim was to study their photosynthetic and respiratory responses to various light intensities. The Phormidium sp. TK1 microbialite was collected at 19 m depth and the P. crosbyanum (Tilden) microbialite was collected at 0.5 and 13 m depth. Phormidium sp. TK1 showed all the characteristic features of a low-light adapted species. The initial slope of the Photosynthesis versus Irradiance curve for this microbialite was close to the maximum quantum yield indicating an efficient light absorption and utilization at low light. The photosynthesis maximum was located 0.2-0.4 mm below the surface and did not shift with changing light intensity. Respiration rates were low and not enhanced by light; photoinhibition was observed at higher light intensities. In Phormidium crosbyanum (Tilden) microbialites, the photosynthesis maximum shifted downward to lower depths with increasing light, probably as a result of phototactic migration of cyanobacterial filaments, and light-enhanced respiration was observed at light intensities above light saturation. The photosynthetic para- meters measured in P. crosbyanum indicate that P. crosbyanum is capable of photo-acclimation at high light intensities. The gross productivity of the different microbialites was comparable to values measured in cyanobacterial stromatolites observed in other shallow environments. However, the microbialites studied here were characterized by a lower respiration / production ratio which indicates a higher growth efficiency.

Chromatography, High Pressure Liquid↗
PubMed2004

The role adaptation process of head nurses in the general hospitals.

PURPOSE: The purpose of this study is to identify the role adaptation process experienced by head nurses. METHODS: Data were collected from 10 head nurses with in-depth interviews about their actual experiences. All the interviews were recorded and transcribed. The collected data were analyzed by the grounded theory methodology of Strauss and Corbin. RESULTS: The core category was identified as "weighing and balancing," and the role adaptation process was divided into six stages by time sequence: inquiring, approaching to others, bringing people into their fold, working with conviction, avoiding conflicts, and settling. CONCLUSION: The results of this study yield useful information for top managers of nursing to identify, by stages, the demands of the head nurses in their role adaptation process. The findings of this study contributes to developing programs that facilitates the head nurses' role adaptation.

Adaptation, Psychological↗
PubMed2005

The lived experience post-autologous haematopoietic stem cell transplant (HSCT): a phenomenological study.

Autologous haematopoietic stem cell transplant (HSCT) has a high physical and emotional morbidity. This study using Husserlian phenomenological methodology and using Giorgi's (Phenomenology and Psychological Research, Dusquesne University Press, Pittsburgh, 1985) method of analysis was undertaken to attempt to gain some understanding of the patient's experience. Five adult patients who had previously undergone autologous transplantation for a haematological malignancy at least 6 months before participated in the study. Interviews with the participants were audio taped and then transcribed verbatim. Nine themes emerged from the participants' stories and included psychological cost, physical and psychological adaptation, reprioritisation and a sense of isolation. The transplant experience can be separated into a discrete period of time and the findings illustrate that the experience of transplantation impacts on the life of the person for an undetermined period of time. The changes experienced may be permanent and the post-transplant person, emotionally, psychologically and physically, is not the same person who entered into transplant. For nurses and other health care professionals to improve practice it is imperative that they understand the lived experience their patients have undergone. Pretransplant preparation and post-transplant rehabilitation can be enhanced by having a greater depth of understanding.

Activities of Daily Living↗
PubMed2004

The contribution of stereo vision to one-handed catching.

Participants with normal (StereoN) and weak (StereoW) stereopsis caught tennis balls under monocular and binocular viewing at three different speed conditions. Monocular or binocular viewing did not affect catching performance in catchers with weak stereopsis, while the StereoN group caught more balls under binocular vision as compared with the monocular condition. These effects were more pronounced with increasing ball speed. Kinematic analysis of the catch partially corroborated these findings. These results indicate that StereoW catchers have not developed a compensatory strategy for information pick-up, and that negative effects of a lack of stereopsis grow larger as temporal constraints become more severe. These findings also support the notion that several monocular and/or binocular information sources can be used in the control of interceptive action.

Adaptation, Physiological↗
PubMed2004

Long-term care of the patient with the atrial defibrillator.

With an aging population, atrial fibrillation is becoming an increasingly common cause of hospital admission. Patients with recurrent, symptomatic persistent atrial fibrillation often require repeated admissions to the hospital for cardioversion. The development of the atrial defibrillator has empowered such patients to take charge of their condition and perform cardioversion on themselves at home. This liberates them from the worry of hospitalization and can increase patient confidence. The implantation of an atrial defibrillator, however, has some disadvantages, and long-term use of the device exposes patients to some of the psychological adaptations that occur in recipients of implantable devices. This article discusses in depth the patient selection process, the implantation procedure, the use of the atrial defibrillator, and problems that can arise during long-term follow-up.

Anti-Arrhythmia Agents↗
PubMed2001

3D after-effects are due to shape and not disparity adaptation.

There are a variety of stereoscopic after-effects in which exposure to a stimulus with a particular slant or curvature affects the perceived slant or curvature of a subsequently presented stimulus. These after-effects have been explained as a consequence of fatigue (a decrease in responsiveness) among neural mechanisms that are tuned to particular disparities or patterns of disparity. In fact, a given disparity pattern is consistent with numerous slants or curvatures; to determine slant or curvature, the visual system must take the viewing distance into account. We took advantage of this property to examine whether the mechanisms underlying the stereoscopic curvature after-effect are tuned to particular disparity patterns or to some other property such as surface curvature. The results clearly support the second hypothesis. Thus, 3D after-effects appear to be caused by adaptation among mechanisms specifying surface shape rather than among mechanisms signaling the disparity pattern.

Adaptation, Physiological↗
PubMed1997

[Use of the laryngeal mask in adenoidectomy in childhood--a comparison with endotracheal intubation].

PURPOSE: Anaesthesia for adenoidectomy is possible during infancy without succinylcholine. One possibility is intubation with vecuronium bromide, whereas another possibility is the use of the laryngeal mask (LMN). The conditions for intubation as well as further details during anaesthesia are listed and compared. METHODS: 200 children are divided into 4 groups. Group A: intubation with thiopental and vecuronium bromide. Group B: LMN with thiopental, Group C and D: as A and B but the thiopental replaced by propofol. The following aspects are compared: the conditions of intubation; circulation conditions; oxygen saturation; the behaviour when coming out of anaesthesia; complications; the assessment by the surgeons. A further control of 100 routine LMN covers the complications which arose. RESULTS: Adenoidectomy can be carried out successfully with both kinds of anaesthesia. Tracheal intubation attained a better assessment by most surgeons and is easier to administer. Brief declines in the saturation of oxygen occur more frequently when using LMN. LMN has its advantages in the low irritation of the respiratory mucous membranes and results in improved behaviour on coming out of the anaesthesia, especially if used with propofol. Problems arise mainly through the use of the mouth clamp which can result in obstructions of the respiratory tract and re-intubation. These problems arise less frequently when the use of this method has become routine. CONCLUSION: LMN takes time to get used to, and places greater demands on the anaesthetist. Success of LMN depends on the cooperation and collaboration to the surgeon to lower the risk of complications. Once specific improvements in the LMN have been made, it may become the standard method for adenoidectomy in future. It is already used by us and in some outpatient departments, as well as in England and America. Our suggestions are as follows: Aims at convincing the surgeons and improving their co-operation; No routine fixation of the laryngeal mask. The laryngeal mask should be kept slightly taut before opening--preferably slowly--the mouth clamp; possible technical modifications of the mouth clamp itself, which produce a wider gap, could be adapted to the new conditions of the wider LM; reaching the necessary depth of anaesthesia through higher doses of propofol or possibly by total intravenous anaesthesia; routine wearing of the LM in the recovery room until it is no longer tolerated by the child.

Adenoidectomy↗
PubMed2006

Population differentiation and the effects of herbivory and sand compaction on the subterranean growth of a desert lily.

Differences in level of herbivory can select for local adaptation and genetic differentiation of plant populations in different environments. Mean bulb depth of the desert lily Pancratium sickenbergeri, differs considerably among populations differing in the level of herbivory by the dorcas gazelle. The gazelle digs in the sand to remove most of the bulb of the lily. Deeper bulbs have less material removed by herbivory than shallow bulbs and have higher fitness. A possible confounding factor is the degree of sand compaction, which may retard the downward growth of the bulb. We conducted a common garden experiment with 2 sand types with seeds from source populations with different levels of herbivory. There was a large genetic difference among populations. Two of 3 analyses indicated that there was an interaction between population and sand type, indicating that there is a heritable component of plasticity.

Animals↗
PubMed2026

Toward simple, rapid, and deep plant proteome analysis with an in-cell proteomics strategy.

While liquid chromatography-mass spectrometry (LCMS) has revolutionized plant proteomics over the past decade, plant sample preparation remains a major challenge due to rigid cell walls, abundant secondary metabolites, and wide dynamic range of protein abundance. These hurdles demand laborious tissue disruption, complex precipitation, and extensive cleanup prior to LCMS analysis, limiting the widespread adoption of proteomic technologies within the plant biology community. To overcome these barriers, we introduced an "in-cell proteomics" strategy that bypasses cell lysis and protein extraction by performing digestion directly inside methanol-fixed cells. We systematically benchmarked this strategy against conventional lysate-based workflows across 4 model plants (Arabidopsis thaliana, Nicotiana benthamiana, Zea mays, and Sorghum bicolor) and 3 tissue types (leaves, pollen, and seeds). Combined with minimal input material and single-shot LCMS, the in-cell approach consistently identified 9,000 to 12,000 proteins from leaves, 7,000 to 9,000 from pollen grains, and approximately 8,000 from seeds. Our comprehensive dataset demonstrates that this in-cell digestion approach substantially simplifies plant sample preparation while delivering proteomic performance equivalent to established workflows. Finally, to demonstrate the biological utility of this approach, we characterized the proteomes of N. benthamiana leaves infected with 2 fungal strains that exhibit different host specificities. Our in-depth proteomic data revealed distinct host response signatures differentiating the host-adapted Colletotrichum destructivum from the nonhost-adapted Colletotrichum sublineola strain. Overall, this study provides a simple, unbiased alternative for plant proteomic analysis that can be readily applied to tackle complex agricultural and physiological challenges in plant biology.

Proteomics↗
PubMed2004

Simulation of surface EMG signals generated by muscle tissues with inhomogeneity due to fiber pinnation.

Surface electromyographic (EMG) signal modeling has important applications in the interpretation of experimental EMG data. Most models of surface EMG generation considered volume conductors homogeneous in the direction of propagation of the action potentials. However, this may not be the case in practice due to local tissue inhomogeneities or to the fact that there may be groups of muscle fibers with different orientations. This study addresses the issue of analytically describing surface EMG signals generated by bi-pinnate muscles, i.e., muscles which have two groups of fibers with two orientations. The approach will also be adapted to the case of a muscle with fibers inclined in the depth direction. Such muscle anatomies are inhomogeneous in the direction of propagation of the action potentials with the consequence that the system can not be described as space invariant in the direction of source propagation. In these conditions, the potentials detected at the skin surface do not travel without shape changes. This determines numerical issues in the implementation of the model which are addressed in this work. The study provides the solution of the nonhomogenous, anisotropic problem, proposes an implementation of the results in complete surface EMG generation models (including finite-length fibers), and shows representative results of the application of the models proposed.

Action Potentials↗
PubMed1984

The constructs 'stress' and 'coping' as a rationale for nursing activities.

In this paper the constructs 'stress' and 'coping' as defined in an earlier paper (Clarke 1984) are used as a perspective for the interpretation of disease processes. The second half of the paper is devoted to an examination of the nurse's role which is seen as concerned with helping patients in the reduction or avoidance of stress and the strengthening of coping. General hospital nursing and district nursing is analysed in greater depth than other types of nursing.

Adaptation, Physiological↗