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At least 217 records · Page 12Linked to original sources
PubMedDate not supplied

Overdose with chloral hydrate: a pharmacological and therapeutic review.

The purpose of this review is to highlight the toxicity of chloral hydrate and to review the management of overdoses with chloral hydrate. Three patients are presented in whom life-threatening cardiac arrhythmias dominated the clinical presentation. These arrhythmias were resistant to standard antiarrhythmic therapy. Also, we have reviewed selected features in eight patients who took overdoses of chloral hydrate who were admitted to an intensive care unit between 1981 and 1988. The pharmacology and toxicology of chloral hydrate are discussed with particular reference to the cardiac arrhythmias that are seen with overdosage. A proposed management scheme is detailed, including intravenously-administered propranolol as the preferred first-line antiarrhythmic agent. A case may be made for the discontinuation of the usage of chloral hydrate.

Adult↗
PubMed1976

Medical recommendations--followed or ignored? Factors influencing compliance in arthritis.

Physiatrists are frequently confronted by the failure of patients to follow medical advice, with resultant adverse effects on rehabilitation outcomes. This paper examines the compliance of arthritis patients with an exercise regimen. A number of factors are examined in this study in assessing elements related to patient compliance. Included are patient attributes and perceptions, professional home visits and form of instruction in the regimen and selected features of the patient's social environment. Age, activity status and marital status, use of medications, patient understanding of arthritis and professional home visits appear to have a bearing upon patient compliance. Careful attention to factors likely to influence patient compliance will prove helpful in efforts designed to enhance rehabilitative progress and, ultimately, improve the lives of patients.

Adult↗
PubMed1992

Ultrasonographic appearance of the uterus, placenta, fetus, and fetal membranes throughout accurately timed pregnancy in beagles.

Serial ultrasonographic examinations were performed on 8 Beagle bitches from 20 to 60 days pregnant to determine time of first detection, appearance, and sizes of selected features of pregnancy. Gestation was timed from the day of the preovulatory luteinizing hormone surge. Findings related to gestational age were consistent among bitches. Gestational ages at earliest detection of the following features were: chorionic cavity at day 20; placental layers in the uterine wall at day 22 to 24; zonary placenta at day 27 to 30; embryo and heartbeat at day 23 to 25; yolk sac membrane at day 25 to 28; allantoic membrane at day 27 to 31; choroid plexus of the brain at day 31 to 35; fetal movement at day 34 to 36; skeleton at day 33 to 39; bladder and stomach at day 35 to 39; kidney at day 39 to 47; and liver hypoechoic, compared with lung, at day 38 to 42. Extra-fetal structures were measurable from day 20 or 22 through day 48. Chorionic cavity diameter increased from 0.2 +/- 0.0 cm to 3.3 +/- 0.2 cm, outer uterine diameter increased from 0.8 +/- 0.03 cm to 4.8 +/- 0.2 cm, length of chorionic cavity or zonary placenta increased from 0.3 +/- 0.03 cm to 4.9 +/- 0.05 cm, uterine wall thickness increased from 0.3 +/- 0.03 cm to 0.8 +/- 0.01 cm, and placental thickness increased from 0.1 +/- 0.0 cm to 0.5 +/- 0.05 cm. Chorionic cavity diameter, outer uterine diameter, and placental length each increased at a linear rate through day 37, after which time, each had a marked plateau in growth. Of the extra-fetal structures, chorionic cavity diameter was the most accurate for estimation of gestational age. All of the fetal structures studied increased at an increasing (second order) rate. Crown-rump length increased from 0.3 +/- 0.05 cm on day 24 to 9.2 +/- 0.2 cm on day 48. Body diameter increased from 0.2 +/- 0.03 cm on day 24 to 4.6 +/- 0.15 cm on day 60. Head diameter increased from 0.8 +/- 0.05 cm on day 34 to 2.7 +/- 0.04 cm on day 60. Of the fetal structures, head diameter was the most accurate for estimation of gestational age.

Animals↗
PubMed1991

The immunobiology of heat shock proteins.

A cell's reaction to heat shock is one of the most conserved responses among evolutionary diverse species. Although selected features of the response may vary between organisms, the synthesis of heat shock proteins is universal. The induction of hsps is rapid and occurs immediately following exposure to only a few degrees above normal physiological temperature. The array of assigned functions as well as those hypothesized for heat shock proteins imply that hsps are designed to render cells capable of coping with a variety of physiological stresses, including heat and oxidative injury. Interestingly, the gene for the hsp70 is located between the complement and tumor necrosis factor genes within the class III region of the human major histocompatibility complex on the short arm of chromosome 6. Hsp70 proteins have been linked with a protective role during stress and as unfoldase(s) in protein translocation into the endoplasmic reticulum and mitochondria. Moreover, hsp analogs are often presented as antigens in bacterial or protozoal infections. The mapping of hsp70 in the MHC region may have significant implications with regard to immune mediated diseases. Moreover, the relationship of hsps to immunity and cancer represents the beginning of a major link of the role of hsps in human pathology. Finally, with its pleiotropic roles in essential cellular physiology and immune function, we predict that future experiments will define a relationship between hsps and allergy.

Animals↗
PubMed1990

Alpha- and beta-adrenergic induction of the expression of the uncoupling protein thermogenin in brown adipocytes differentiated in culture.

In order to examine the control of expression of the gene coding for the brown fat specific uncoupling protein thermogenin (UCP), brown fat cells isolated as undifferentiated precursors from the interscapular brown adipose tissue of young mice were grown in culture. In these cells, it was possible by norepinephrine (NE) addition to induce specifically the expression of the UCP gene. The effect of NE was due to activation of transcription. The ability to express the UCP gene was maximal in cells around confluence; cell cultures younger or older than this showed a lower response. The response to NE showed a sharp optimum around 0.1 microM and was linear with time over the 4-h period studied. The presence of insulin or thyroid hormones facilitated the NE response. Pharmacological analysis of the adrenergic response indicated that UCP gene expression could be induced both via beta-receptors (probably beta 3) and via alpha 1-receptors; these effects were synergistic. It was concluded that it is possible to promote these precursor cells to advance to such a state of differentiation that they can demonstrate the selective feature of the brown fat cell, i.e. the ability to express UCP. The expression of the UCP gene is regulated via interacting adrenergic mechanisms.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1991

[Postnatal cellular pleomorphosis in retinal pigment epithelium].

Selected features of cell morphology of the retinal pigment epithelia (RPE) were compared in newborn (42 eyes) and adult albinotic rats (34 eyes) at the age of 9 months. The RPE of newborn rats was found to consist of nearly homeomorphous, hexagonal, mononucleate, and relatively small cells (monomorphism). Minimal regional differences were found to exist. In adult albinotic rats the density of the RPE cell population was found to be considerably reduced, but the cells and nuclei were generally enlarged. A high percentage of RPE cells was found to contain two nuclei, and as a rule there were always some cells with three, four or even more nuclei. The picture of the cell mosaic was characterized by marked pleomorphism with regionally determined graduation. Pleomorphous changes were more pronounced in the central than in the more peripheral areas. The genesis and dynamics of cellular pleomorphism are also discussed.

Animals↗
PubMed1990

Signal analysis for ECG interpretation.

In ECG interpretation usually two main areas are discerned: the signal analysis and the diagnostic classification. This article reviews the major developments in the first area. ECG signal analysis itself is subdivided into the stages data acquisition, data transformation, feature selection, and data reduction. These stages are consecutively reviewed, while in the data transformation stage digital filtering, detection, wave typing, beat selection, and boundary recognition are discussed.

Algorithms↗
PubMed1990

Predictive value of intraoperative liver biopsies of donor organs in patients undergoing orthotopic liver transplantation.

The evaluation of prerevascularization and postrevascularization biopsies in comparison with clinical and laboratory data has revealed a direct correlation between elevated PT and AST levels and pericentral and panlobular individual hepatocyte necrosis. No other significant correlations were determined when comparing selected histologic features to selected clinical laboratory values. In conclusion, these biopsies are of limited use in predicting subsequent allograft function in the absence of prominent individual hepatocyte or pericentral necrosis.

Adult↗
PubMed1990

[The use of the method of principal components for phenogenetic analysis of the integral domestication trait].

In the course of long-term experiment on domestication of silver fox, it was necessary to determine the most important behavioral features, selection for which would give domestication effect. The mathematical method of principal components was used for the analysis of 20 fox behavior traits. The combination of the initial traits which reflected the structure of the integral trait, i.e. domesticated type of behavior, was determined. The practical use of this combination seems to more adequately estimate the level of domestication of a given animal, which is indispensable for subsequent effective selection.

Animals↗
PubMed1989

Fully automated measurements by light microscopy of tissue sections using a cellular array computer.

Software was developed for the acquisition, segmentation and analysis of microscopic OD-images on a VICOM digital image processor, extended with a VISIOMORPH morphoprocessor board. The delineation algorithms for peroxisomes, lysosomes, and nuclei in liver, kidney, and adrenal gland sections start by thresholding the difference between the original image and a low pass filtered version. The resulting binary mask is then processed by morphological operations in order to produce an object overlay. The efficiency of the programs is evaluated by comparing delineated objects at different OD-levels, created by varying the stain or by multiplying the original pixel values with constant factors. Manual delineation on some images is also used as a reference. More complex algorithms are used for the delineation of muscle fibres in ATP-ase-stained sections and immunocytochemically labelled cells in monolayer preparations. Muscle images from parallel sections with different stainings are matched with a coordinate transform, enabling the transfer of the object mask from a single delineated image to the unprocessed images and thus obtain all necessary information for fibre classification. After segmentation, the OD-images and their object overlays are fed into a data extraction program, measuring for each delineated object user-selected features. Data are sent to a VAX for statistical interpretation.

Adrenal Cortex↗
PubMed1989

Karyometric marker features in tissue adjacent to invasive cervical carcinomas.

A companion study showed the existence of statistically significant changes in the value of karyometric "marker features" in the nuclei of histologically normal-appearing ectocervical epithelium adjacent to carcinomas in situ. In this second part of the study, the results obtained in patients with invasive cervical carcinomas were analyzed. Formalin-fixed, paraffin-embedded tissue sections were Feulgen stained and analyzed with a microTICAS video microphotometer. The results, demonstrated for the first time in histologic material, indicate that the marker features are clearly expressed in a majority of nuclei observed in the normal-appearing tissue adjacent to invasive lesions. This effect was statistically significant. The best marker features selected by the discriminant analysis were nuclear roundness, nuclear perimeter length, total optical density and a run length texture measure. These findings may reflect a subtle transformation of the apparently normal cervical epithelium adjacent to an invasive cervical carcinoma.

Carcinoma↗
PubMed1987

Discounting an adverse maternal effect on severity of neurofibromatosis.

Neurofibromatosis, a common, progressive, autosomal dominant disorder, is markedly variable in its expressivity. Some authors have suggested that some contribution to neurofibromatosis's variability may be an adverse effect of a mother's neurofibromatosis on the overall severity seen in her offspring with neurofibromatosis. In the present study of 188 maternal affected, paternal affected, and sporadic von Recklinghausen neurofibromatosis cases, the maternal influence question was systematically examined. Overall severity, selected features most likely to reflect in utero maternal influence, and other common neurofibromatosis-I features were analyzed statistically. Age, racial composition, and gender of the three groups were similar. No significant differences were found (P less than or equal to .01) between maternal affected, paternal affected, and sporadic cases in terms of overall severity, probability of reaching advanced severity as a function of age, indications of possible prenatal influence (eg, congenital neurofibromas, tibial pseudarthrosis), or other neurofibromatosis features. These results demonstrate that the nature and severity of neurofibromatosis for maternal affected cases are essentially the same as for paternal affected and sporadic cases.

Adolescent↗
PubMedDate not supplied

[Dynamics of the age structure of residents in homes for the aged and nursing homes].

In state-run residential and nursing homes in the GDR the proportion of those residents of at least 80 years of age increased from 41.5 to 56.0 p.c. between 1980 and 1983, diversified on districts they moved between 70.0 and 46.5 p.c. Some selected features were correlated, only a low degree of dependence being found on the age-structure of the district-population (r = +0.26), highest degree on the ratio home-capacity/district-population (r = -0.65).

Aged↗
PubMed1982

Occupational mortality and morbidity in relation to selective turnover.

Because of the "healthy worker effect" most occupational cohorts, especially those of persons doing physically heavy work, are selected groups with regard to life expectancy. Health selection is also involved in turnover. Mortality and morbidity were studied on three different exposure levels, defined primarily according to physical demands: heavy level (iron foundries), medium level (manufacture of metal products), and light level (manufacture of electrical devices). The population comprised about 15,700 men who were employed in 1950-1976 in the three branches of the metal industry representing the different levels. The number of person-years of follow-up became about 215,800. During the period 1950-1978, there had occurred 1,407 deaths. Data for the mortality and disability analyses were obtained from the national death and disability registers. Occupational history, morbidity, and reasons for turnover were studied in a sample by means of questionnaire sent to 400 current and 600 former workers from each branch. In addition, a questionnaire concerning occupational history was sent to the next of kin of 450 dead persons. When the three cohorts were compared to the general male population of Finland, the standardized mortality ratio was 124 for the foundry workers, 92 for the metal product workers, and 107 for the electrical workers. The survival curves showed no great differences between the three exposure levels. However, the heavy level had the highest degree of mortality, and the medium level the lowest. Foundry workers showed less social selection than the two other cohorts. Metal product workers seemed to be socially and health selected. Economic fluctuations clearly regulated entries of new employees into the industries and thus introduced additional selective features.

Adolescent↗
PubMed1981

Leukemia revisited.

Selected features of the historical development of our knowledge of leukemia are discussed. The use of different methodologies for study of the nature of leukemic cell proliferation are analyzed. The differences between older cell kinetic data using tritiated thymidine and autoradiography and the newer cell culture methods are more apparent than real. It is suggested that tritiated thymidine and extracorporeal irradiation of the blood may be useful for therapeutic agents that have not been given an adequate trial. Radiation leukemogenesis presents an opportunity for study of the nature of leukemogenesis that has not been exploited adequately.

Animals↗
PubMed1981

[Metric examinations on the development of apical dendrites of cortical pyramidal cells during the postnatal time in the rat].

1. It is explained the postnatal evolution of some selected features of Golgi-impregnated layer V pyramidal neurons in the rat sensorimotor cortex from the 1st to the 90th day after birth (13 stages) quantitatively. Especially it is reported about the development of the length and the quantity of apical main dendrites and of the apical lateral branches from the 1st to the 3rd order as well as the branching behaviour of the dendrites (free ends of dendrites, branching points, ramification index). 2. The evolution of mean length of apical dendrites is represented by a sigmoidal polygon trace - like the classic growing curve. 3. During the 3rd month of the postnatal life the lateral branches of the apical dendrites show a distinct growing increase relating to the mean values of the total length of dendrites, their quantity and the branching behaviour. This intensification of growth is in contrast to the growing stagnation of the apical main dendrites in this time. 4. From this point of view it is deduced that relating to the maturation of pyramidal cells - contrary to the papers of other writers and contrary to a previous private conception - albino rats in the age of 3 months do not are differentiated cortical completely. 5. The several marks of pyramidal dendrites do not form themselves in the same time but successively. The maturing process of new dendrites or dendrite branches is the base of significant increase of the length. 6. It seems, that the formation of dendritic "tree" takes place in growing batches. In this context there are discussed the correlations between the morphometric conceivable changes in the cortical pyramids and the accession of functions in the animal.

Animals↗
PubMed1980

Aytpia status index of respiratory cells: a measurement for the detection and monitoring of neoplastic changes in squamous cell carcinogenesis.

A statistical procedure was developed for calculating an atypia status index (ASI) for cells from the bronchial mucosa. These indices represent the degree of abnormal changes in these cells and classify them as squamous metaplasia, mild atypia, moderate atypia, servere atypia or carcinoma. The classification accuracy of the procedure was more than 99% on trained data and was accomplished by minimizing the overlapping areas between the adjacent multivariate distributions of cell groups for selected features whose group means represent a monotonic function and for which the cell categories are distinguishable. The calculated ASI may reflect abnormal changes in the cell that may not be clearly evident visually. It appears that progression or reversal of bronchial epithelial atypia can be accurately monitored by studying the changes in the ASI, not only for preneoplasia but also for reactions to chemotherapy and various pulmonary infectious disease processes, such as influenza.

Adult↗
PubMed1995

Issues and challenges in the design of curriculum information systems.

Medical schools are increasingly using curriculum information systems to better manage their curricula, to incorporate alternative learning environments, to expand subject-specific instruction, or to adapt the curricula to the changing health care environment. A curriculum information system contains key features, selected by the system's designers, that describe the objectives, the specific content, and/or the educational activities that compose the curriculum. The underlying purpose of such a system is to document and describe the knowledge, behaviors, skills, attitudes, or activities students will be expected to develop or learn. While it might be ideal to have one system that would meet the needs of all possible users, the programming and maintenance requirements of such a single system would exceed most medical schools' resources. Thus, designers of curriculum information systems must first identify the primary intended-user group: students, faculty, or administrators. The system designed for one group will typically differ from the systems for other groups in the emphasis on and level of content detail and curriculum structure information. The general structure and purposes of curriculum information systems are expressed in three distinct system designs: a curriculum database (most helpful for administrators), a curriculum textbase (for faculty), and an electronic syllabus (for students). The authors describe these different designs, and they discuss challenges faced by system designers.

Curriculum↗