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At least 73 records · Page 4Linked to original sources

PubMed1988

In vivo effects of glucocorticoid excess on the contents of the rat fetal liver in erythroid progenitors.

Following a laparotomy of the pregnant rat at 12 days of gestation, erythroid cell suspensions prepared from the fetal livers at 14 days contained an increased proportion of progenitor cells forming colonies after 2 or 7 days of culture. When laparotomy was performed at 14 days and the fetal livers were sampled at 16 days, the opposite effects were observed. Injection of 0.25 mg/kg dexamethasone to the 12 days pregnant rat increased the proportion of erythroid progenitors in suspensions from 14 days fetal livers; injection of 10 mg/kg (a long-acting dose) produced the opposite effects. Both the composition of the erythroid cell line and its environment change between 12 and 14 days, and these modifications might explain the inversion of glucocorticoid effects between these two stages.

Animals↗

PubMed1984

"Race related illness in Vietnamese refugees".

The author worked for six weeks in September 1982, as a Medical Practitioner and Psychiatrist at the first Asylum Centre Puerto-Princessa, Palawan, Philippines. This paper relates relevant aspects of Mental Health needs of Vietnamese refugees related to racism, aftermath of war, leaving home-land without preparation, perilous escape, prolonged stay in cramped refugee camps, and move on to unsettled, unsure future in another country with alien culture and environment. Changes of life situation, loss of business, property or occupation, loss of loved ones, separation from friends, disruption of family relationships are related to racism and persecution elements in 'Boat People'. The most frequent psychiatric illnesses among the refugees are: depression, anxiety state, psychosomatic disease and psychosis. A special mental health project is needed to train health workers, provide service and consultation and to organising research activities. On the preventive aspects, primary prevention may be achieved by less stress on rapid assimilation and the reduced likelihood of discrimination, hostility and prejudice. Secondary prevention consists of early detection of the disease and early initiation of treatment and tertiary prevention consists of the elimination or reduction of residual disability after an illness.

Adult↗

PubMed1977

Development of stress-induced pituitary prolactin and TSH release in male rats.

Blood was collected from male rats of various ages under control conditions and after introduction of two stress factors. All animals were sacrificed between 15.00 and 16.00 h. Serum prolactin levels in immature male rats were found to be very low between birth and day 15 after birth. Neither exposure to a new environment, for example removal from the animal rooms for the duration of 10 min, nor exposure to concentrated ether vapour resulted in increased serum prolactin levels. Between day 20 and 35 basal serum prolactin levels were increased, they then fell at adult values. During this period of increasing serum prolactin levels pituitary prolactin release became stress-susceptable; i.e. elevated serum prolactin levels were observed after introduction of stress factors as in adult male rats. Serum TSH levels were found to be high between birth and day 10. Low TSH levels measured between day 15 and 40 and adult values were detected after day 40. Neither ether nor removal of the animals from their normal environment changed serum TSH levels at any age tested. The results indicate that the hypothalamo-pituitary in immature rats reacts in a similar way as that in adult animals from day 16-20 onwards. Serum TSH levels in these animals, however, are reduced, indicating that an increase in serum TSH is not necessary for normal processes of maturation.

Age Factors↗

PubMed1988

Divergent selection for growth in Japanese quail under split and complete nutritional environments. 1. Genetic and correlated responses to selection.

Japanese quail were divergently selected for 4-wk body weight under two different nutritional environments. In one environment quail were divergently selected for high and low body weight (H and L) under a split diet (SD) with quail having the opportunity to self-select feed from high protein and high energy diets. In the other environment, quail were similarly selected (H and L) under a normal (28% protein) complete diet (CD). After 11 generations of selection, H-SD and H-CD lines were 48.9 and 49.7% higher in 4-wk body weight than controls. Quail from L-SD and L-CD lines were 46.5 and 45.4% lower in 4-wk body weight than controls. Realized heritabilities for 4-wk body weight were .36 +/- .03, .30 +/- .03, .52 +/- .02, and .47 +/- .03 for H-SD, L-SD, H-CD, and L-CD lines, respectively. Selection differentials were significantly higher in the SD than in the CD environment. Changes in 2-wk, adult body, and egg weight across generations paralleled that of the trait under selection (4-wk body weight). Selection also resulted in decreased hatchability and egg production with increased age to sexual maturity in both environments. The SD environment was determined to be a stress environment because of birds' inferior growth there compared with growth in the CD environment. Rate of growth, however, to reach adult body size was superior for L-SD quail once the stress environment was removed. There was also evidence that eggs were larger for quail in the SD than the CD environment.

Animals↗

PubMedDate not supplied

Individualized enhancement programs for nurses that promote competency.

Working in a cost-conscious health care environment changes the accessibility to conferences, workshops and other continuing education offerings. Educators, employers and individual nurses are compelled to be innovative in their approach to maintaining competency through continuing education (CE). Greater emphasis must be placed on effectively matching CE programs with carefully targeted learning needs. This article illustrates a four-phase approach to an individualized enhancement program that incorporates job expectations and competencies. The phases are: 1) completing a needs assessment, 2) defining learning objectives, 3) assessing available learning resources, and 4) evaluating the CE experience.

Clinical Competence↗

PubMed1990

The immuno-suppressed patient--what are the implications?

Dentists, doctors, and other health professionals are increasingly involved in interacting with immunosuppressed and immuno-deficient patients. As the medico-legal and health-economic environments change, an increasing range of progressively more difficult problems is developing. Like other health professionals, dentists must accept their role as advocates for patients, despite the stresses that this will entail. The psychological and social stresses inherent in handling life-long management problems based upon immuno-suppression and immuno-deficiency exceeds the hazards to dentists and others which result from exposure to various viruses and bacteria. There are implications in terms of history taking, organisation of laboratory and organ-imaging investigations, for continuing education, and for intra-professional referral procedures.

Attitude↗

PubMed1989

Toward the necessary universalizing of a disability policy.

Issues confronting people with disabilities do not result solely from physical or mental impairment, but from the fit between impairments and practically every feature of the social, economic, physical, and political environment. Changes in housing, transportation, and employment policies would augment the quality of daily living for those with disabilities today and in the future. With the entire population facing chronic illness and activity limitations, a universal approach to disability is virtually required, rather than policies focusing exclusively on a person's special needs. The absence of such a universal perspective will lead to the expansion and perpetuation of the segregated and unequal society visible at present.

Aged↗

PubMed1988

Polymorphism of rat gastric mucosal histidine decarboxylase: effects of the coenzyme and sulfhydryl groups.

Several factors are examined for their implication in the charge heterogeneity and form conversion of rat gastric mucosal histidine decarboxylase. The apoenzyme and the holoenzyme are undistinguishable with respect to their pI and to the distribution of enzyme activity in the three forms. The latter are not produced by differential coenzyme binding. Studies for glycoprotein characterization provide evidence that the heterogeneity does not arise from enzyme-bound carbohydrate. Oxidative or reductive environments change the distribution between forms without modifying the molecular weight. Conversion of form III to forms I and II can be effected by treatment with dithiothreitol. A similar loss of negatively charged form occurs upon ageing and is not prevented by an alkylating agent. All three forms show equal sensitivity to N-ethylmaleimide and dithiothreitol inhibitions. The oxidation-reduction state of exposed sulfhydryl groups may be responsible at least in part for the charge heterogeneity.

Animals↗

PubMed1986

Developmental concerns and the health of midlife women.

Prior to providing anticipatory guidance to a woman approaching or at middle age, the nurse should explore her own and her client's expectations of middle age and work to dispel any existing myths. Menopause is not inevitably a time of increased depression or nervous symptomatology. In addition, women whose children are gone from the home are not at increased risk for depression or low life satisfaction. However, we do know that the majority of women experience vasomotor symptoms including hot flashes and night sweats which are directly attributable to the hormonal changes accompanying menopause. The middle-aged woman may begin to note changes in her physical appearance and level of physical energy. This point in life can also be associated with a variety of transitions, including changes in the parental and marital role, the care and death of aging parents, and the loss of a spouse through death or divorce. As the familial environment changes for a woman, work outside the home may take on a different meaning. This stage of life can be one of growth as the woman seeks new directions or it can be a time of dissatisfaction. No one factor distinguishes those who cope well from those who do not. When identifying those women at risk for midlife developmental crises, the nurse must consider the interaction risk for midlife developmental crises, the nurse must consider the interaction of multiple factors. Preliminary evidence suggests that some women may experience a decreased sense of life satisfaction at the time of menopause.(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptation, Psychological↗

PubMed1986

Regulation of hematopoiesis in rats exposed to antiorthostatic hypokinetic/hypodynamia: II. Mechanisms of the "anemia".

Results are presented which demonstrate a close similarity between the ability of antiorthostatic hypokinetic/hypodynamia and orthostatic hypokinetic/hypodynamia to induce anemia in laboratory rats. The "restraint anemia" (whether mediated directly by reduced activity or indirectly by possible changes in blood circulation or in altered weight-bearing capacity of the skeleton) was largely due to reduced food and/or water consumption and displayed the classical symptoms of inadequate nutrition, i.e. decreased serum erythropoietin (Ep) titers and reduced Ep sensitivity of hematopoietic tissue. Only changes in red blood cell (RBC) clearance were unique to the head-down (antiorthostatic) posture. During suspension, RBC clearance was reduced and then accelerated when suspension was terminated or the cells transfused into a normal environment. Changes in RBC clearance were due to both cell-associated and cell-independent factors and may be related to the alterations in RBC survival seen in rats during or immediately after space flight. In both suspension and weightlessness, these changes were limited to alterations in the force and/or direction of the gravity vector.

Anemia↗

PubMed1967

Qualitative and quantitative characteristics adult Culex pipiens fatigans populations according to time, site and place of capture.

The composition of a vector population is largely influenced by the pressures and modifying effects of the environment. Changes in the latter, whether natural or induced (e.g., by insecticides) will be reflected in the former. Thus if the existing characteristics of a vector population are determined, the parameters can subsequently be used to assess the effect of control measures.The effect of environmental conditions on the density and parity of Culex pipiens fatigans in catches in Burma is illustrated by a comparison of results obtained in Kemmendine, which is served by a bucket system for the removal of night-soil, with those from South Okkalapa, which has pit latrines; in the latter area there is a large preponderance of young mosquitos in the monsoon period, in contrast to the situation in Kemmendine.In Kemmendine, the inside-biting catch is reduced by about one-half if an inside-resting catch is made simultaneously. This suggests that C. p. fatigans rests indoors before biting indoors and that an efficient insecticide for inside application would markedly reduce the mosquito population. When a correction is made for the inside-resting catch it is shown that there is little to choose between inside- and outside-biting catches as measures of the activity of C. p. fatigans. The chances of acquiring infection are at least as great out of doors as indoors and this may account for differences in infectivity among different ethnic groups, according to the extent that they sleep out of doors.Differences in parity and in the state of infection of mosquitos according to the type of catch and the time of catching are discussed. Finally, it is noted that, although most male mosquitos are obtained in inside-resting catches, a considerable number, surprisingly, are taken on bait; the reason for this is not yet known.

Adaptation, Biological↗

PubMed1977

Carboxyhaemoglobin saturation in relation to smoking and various occupational conditions.

The effects of smoking and occupational conditions on COHb saturation were studied among employees on traffic duty, in restaurants, in iron foundries, and in an office. The subjects were 139 smokers and 152 nonsmokers working in the same environments. Changes in COHb saturation were observed in samples of blood obtained before and after the working period. Samples of air were collected during the working hours in restaurants, in foundries and in office, 190 samples in all, for the determination of content of CO. Among the nonsmokers there was no change in COHb saturation in restaurants and in office work. On traffic duty and in iron foundries the increase was significant, but the values after work were less than half the permitted occupational threshold limit value (TLV) level of 6 per cent units. In the smoking group the mean values of COHb saturation before work were about twice the mean COHb saturation in the nonsmokers after work. In office work and in foundries the mean COHb saturations after the work exceeded the permitted TLV.

Adolescent↗

PubMed1982

In vivo distribution of carrier protein/67Ga-complexes.

The uptake of 67Ga as citrate, chloride and complexed by carrier-proteins (lactoferrin and transferrin) has been studied in tumor- and inflammatory lesion-bearing rats. Different uptake patterns are shown by tumors and lesions. 67Ga-transferrin complexes are taken up to the highest extent by tumors and inflammatory lesions. The comparative distribution studies using normal animals indicate a systemic increase of 67Ga uptake by tumor- and lesion-bearing animals which might be of importance in explaining the mechanism of 67Ga accumulation. The role of ionic environment changes and radioactivity concentration by isomorphous ionic replacement is discussed.

Animals↗

PubMed1981

Is the doubly deleted alpha-thalassemia gene a "fugitive" allele?

The alpha-thalassemias (particularly in Asia) can be considered as a three-allele system, with one "normal" allele (N) consisting of a pair of closely linked alpha-chain loci, a second "single" allele (S) in which one of the loci has been lost by deletion, and a third "double" allele (D) in which both have been lost. Representatives of all the sets of fitnesses leading to the maintenance of this condition by selection for malaria resistance have been explored, and after the discarding of unlikely sets of fitnesses, it is found that there will be three outcomes: (1) the S chromosome is fixed, (2) the S and N chromosomes form a stable polymorphism, and (3) the N and D chromosomes form a stable polymorphism, but this can be lost and the population forced to fixation by the introduction of sufficiently large number of S chromosomes. Some Melanesian populations appear to have reached outcome (1), while frequencies in African, Mediterranean, and Middle Eastern populations are not incompatible with outcome (2). Southeast Asian populations, however, which carry S and D chromosomes in high frequency, may be in a state of flux. The D chromosome may form a polymorphism with N locally, but it can be driven from the local population by the introduction of large numbers of S chromosomes. The D chromosome would thus be somewhat analogous to a fugitive species, which can only exist in certain transient environments and is displaced as the environment changes. The possibility that N, S, and D are coexisting as a stable polymorphism can almost certainly be ruled out by a consideration of fitness sets required.

Alleles↗

PubMedDate not supplied

Iron, intracellular calcium ion, lipid peroxidation and carcino-genesis.

The evaluation of the accumulated experimental results on the action of complexed iron on cells indicates that the provoked cell injury is rather the consequence of an inhibition of the cytosolic Ca2+ concentration regulatory system than an effect of iron-induced lipid peroxidation. The role of the consequent intracellular ionic environment change in the preneoplastic and neoplastic transformation of the cell is discussed.

Animals↗

PubMedDate not supplied

Moving from the operating room to home care.

Although a change in career can be frightening, a nurse can reap many benefits in a change to home care nursing. With the health care environment changing, home care is increasing and offers a nurse a chance to refresh her enthusiasm for individual patient care and put to use her collective skills learned along the way.

Career Mobility↗

PubMed1976

Lac Repressor. Fluorescence of the two tryptophans.

By comparing the fluorescence emission properties of the wild type lac repressor with two lac repressors altered at tryptophan 190 and 209, respectively, we show that tryptophan residue 209 has its environment changed, either by its own motion, or that of the surrounding amino acids when an inducer molecule is bound. Substitution of this tryptophan with other amino acids results in lac respressor molecules with reduced affinity for inducer molecules, indicating that the geometry at residue 209 affects the geometry of the inducer-binding site. From the results of potassium iodide quenching of fluorescence from the tryptophans, and from attempts to react the native lac repressor with dimethyl(2-hydroxy-5-nitrobenzyl) sulfonium bromide and 2-hydroxy-5-nitrobenzyl bromide, we propose that tryptophan residue 209 is involved in a conformational change of the protein upon binding of inducer, but does not come in direct contact with inducer.

Amino Acids↗

PubMed1994

Reorganization: premises, processes, and pitfalls.

As the technological environment changes and libraries assume new and more active roles in their institutions, the traditional library hierarchy ceases to be an effective organizational structure. Guided by theories that emphasize teamwork, quality, and employee empowerment and participation, libraries are developing flatter, more networked organizations. The Health Sciences Library at Columbia University in New York, New York, recently underwent a reorganization in an effort to become a more resilient, more flexible organization. The process was beneficial overall. While some errors and confusion occurred, these are seen as opportunities for learning and evidence of the library's new atmosphere of creativity and experimentation.

Hospital Restructuring↗