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PubMed1990

Professionalizing domesticity: a synthesis of selected nursing historiography.

The 19th century consolidation of the ideology of domesticity and the ideology of professionalism paralleled the evolution of nursing as a formal occupation for women. Efforts to combine these ideologies, which are based on markedly different foundational assumptions, have been central to the history of American nursing. A meaningful understanding of nursing's history necessitates a synthesis of the interpretations generated by individual historians who have studied similar events in nursing's past. Three feminist historians have studied the professionalizing process in nursing. Generated from diverse perspectives and source materials, the work of these historians illuminates the tensions resulting from nursing's efforts to blend the ideologies of domesticity and professionalism and provides insight into the lessons that can be learned from history.

Female↗
PubMed2025

Parallel genetic adaptation amid a background of changing effective population sizes in divergent yellow perch (Perca flavescens) populations.

Aquatic ecosystems are highly dynamic environments vulnerable to natural and anthropogenic disturbances. High-economic-value fisheries are one of many ecosystem services affected by these disturbances, and it is critical to accurately characterize the genetic diversity and effective population sizes of valuable fish stocks through time. We used genome-wide data to reconstruct the demographic histories of economically important yellow perch (Perca flavescens) populations. In two isolated and genetically divergent populations, we provide independent evidence for simultaneous increases in effective population sizes over both historic and contemporary time scales including negative genome-wide estimates of Tajima's D, 3.1 times more single nucleotide polymorphisms than adjacent populations, and contemporary effective population sizes that have increased 10- and 47-fold from their minimum, respectively. The excess of segregating sites and negative Tajima's D values probably arose from mutations accompanying historic population expansions with insufficient time for purifying selection, whereas linkage disequilibrium-based estimates of Ne also suggest contemporary increases that may have been driven by reduced fishing pressure or environmental remediation. We also identified parallel, genetic adaptation to reduced visual clarity in the same two habitats. These results suggest that the synchrony of key ecological and evolutionary processes can drive parallel demographic and evolutionary trajectories across independent populations.

Animals↗
PubMed2000

Ultrametricity in three-dimensional edwards-anderson spin glasses

We perform an accurate test of ultrametricity in the aging dynamics of the three-dimensional Edwards-Anderson spin glass. Our method consists in considering the evolution in parallel of two identical systems constrained to have fixed overlap. This turns out to be a particularly efficient way to study the geometrical relations between configurations at distant large times. Our findings strongly hint towards dynamical ultrametricity in spin glasses, while this is absent in simpler aging systems with domain growth dynamics. A recently developed theory of linear response in glassy systems allows us to infer that dynamical ultrametricity implies the same property at the level of equilibrium states.

Journal Article↗
PubMed1989

Inhibitory effect of gabaculine on 5-aminolevulinate dehydratase activity in radish seedlings.

We have compared the activity of 5-aminolevulinate dehydratase (5-ALAD) with the amount of protein detected by specific antibodies in rocket immunoelectrophoresis. Parallel kinetic evolutions of enzymic activity and amount of antigen were observed in radish (Raphanus sativus L.) cotyledons, both in complete darkness or under standard far red light involving phytochrome. However, the treatment of seedlings with gabaculine leads to an important decrease in enzymic activity, while the specific protein content is maintained. This inhibition is not overcome by the addition of glutamic acid, but by 5-aminolevulinic acid which points to a specific control of 5-ALAD activity by its substrate. As there is no discrepancy between the enzymic activity and the amount of antigen during the time course development of seedlings, this could confirm a coordinate cellular control between 5-aminolevulinic acid formation and 5-ALAD protein synthesis, both being amplified by the action of phytochrome.

Journal Article↗
PubMed2001

Transition from the incommensurately modulated structure to the lock-in phase in Co-åkermanite.

The adaptation of the incommensurate structure modulation in Ca(2)CoSi(2)O(7) (dicalcium cobalt disilicate) single crystals to decreasing temperature has been examined using in situ high-resolution transmission electron microscopy and electron diffraction. The transition from the incommensurate to the commensurate lock-in phase of Co-åkermanite exhibits a pronounced hysteresis of a highly strained metastable state with a characteristic microdomain morphology. A network of domain walls surrounding single orientation domains develops out of the room-temperature tartan pattern, the domains increase in size and their alignment changes from crystallographic to random. At 100 K the phase transition becomes almost complete. In parallel, the evolution of the modulation structure can be described by a change from a loose arrangement of octagonal tilings into a close-packed configuration of overlapping octagons in the commensurate low-temperature lock-in phase. Thereby, the octagon represents the ordered distribution of low-coordinated Ca clusters within a nanodomain extending over 4 x 4 subunits, on average [Riester et al. (2000). Z. Kristallogr. 215, 102--109]. The modulation wavevector was found to change from q(1,2) = 0.295 (a* +/- b*) at 300 K to q(1,2) = 0.320 (a* +/- b*) at 100 K.

Journal Article↗
PubMed1981

Aspirin prevention of cholesterol gallstone formation in prairie dogs.

When prairie dogs (Cynomys ludovicianus) are fed a diet containing cholesterol, a marked increase in gallbladder mucin secretion parallels the evolution of cholesterol supersaturated bile. Gelation of mucin precedes the precipitation of cholesterol liquid and solid crystals and the development of gallstones. Aspirin given to prairie dogs inhibited mucin hypersecretion and gel accumulation and prevented gallstone formation without influencing the cholesterol content of supersaturated bile. This suggests that gallbladder mucin is a nucleation matrix for cholesterol gallstones.

Animals↗
PubMed1985

Systemic response to local urate crystal induced inflammation in man: a possible model to study the acute phase response.

The production of a systemic inflammatory response to intradermal monosodium urate crystal injection is described. A transient, self-limiting local response is associated with a systemic response detectable by a rise in the white cell count and serum amyloid A protein. The white cell change parallels the evolution of the local response, whereas the serum amyloid A response lags behind the local lesion, peaking after the local lesion is resolving. Intradermal monosodium urate injection is proposed as a possible inflammatory stimulus to explore the acute phase protein response in different disease states.

Acute Disease↗
PubMed1993

Correlation of interleukin-2 and soluble interleukin-2 receptor with clinical activity of multiple sclerosis.

Concentrations of interleukin-2 (IL-2) and soluble IL-2 receptor (sIL-2R) in serum and CSF samples were measured in 63 patients with multiple sclerosis (MS) to evaluate their usefulness as markers of disease activity. CSF concentrations of IL-2 and sIL-2R were significantly higher in MS relapse compared with MS patients in remission or with control subjects. These concentrations correlated with the clinical score by which disease severity was assessed, with the number of relapses per year, and with the total disease duration. Furthermore, there was evidence of intrathecal release of IL-2 and sIL-2R in clinically active MS. The results extend the notion that an activated cellular immune state parallels the evolution of the pathological process in MS and suggest that measurement of IL-2 and sIL-2R concentrations may provide an objective marker of disease activity in patients with MS.

Adult↗
PubMed2004

Intravascular stents in the last and the next 10 years.

The first balloon-expandable coronary stent was approved "for the prevention of restenosis" in 1994, the same year that the Journal of Endovascular Therapy was inaugurated. Since then, the development of the stent has paralleled the evolution of endovascular intervention as a new specialty. Innovators have pushed to explore new and varied stent applications outside the coronary arteries. Carotid stenting, transjugular intrahepatic portocaval shunts, and covered stents are a few of these new applications that have now become commonplace. Dozens of stent designs and several new materials have been tested to solve the problem of in-stent restenosis, but it is the drug-eluting stent (DES) that has emerged as the most promising, at least in the coronary arteries. However, the benefits of DES technology are not likely to be effective in the more pervasive forms of in-stent restenosis, such as encountered in the femoropopliteal segment. In the future, technologies aimed at stimulating rather than inhibiting tissue response to an implant may be part of the next wave of developments, as we take aim against the poor and/or slow tissue incorporation that manifests as leaks and dislodgement. In the superficial femoral artery, for example, mechanical stresses that cause fractures and dislocations may be addressed by using a very flexible endovascular device with a tissue-friendly inner surface that promotes rapid stent endothelialization to counter the biological effects of motion and microtrauma. The rapidly developing fields of nanotechnology, microelectronics, and advanced materials technology will enable the surface engineer to design molecular-specific surfaces for a new generation of vascular devices. Interactive implantable or injectable microdevices aimed at providing specific information upon demand from an external source will revolutionize disease prevention, as emphasis shifts toward monitoring cardiovascular risk exposure. There is no doubt that during the next 10 years, we will witness impressive technological progress in the field of cardiovascular implantable devices.

Femoral Artery↗
PubMed1981

Antibody-induced degradation of acetylcholine receptor in myasthenia gravis: clinical correlates and pathogenetic significance.

Sera of myasthenic patients containing anti-AChR antibodies increase the rate of degradation of mammalian AChR. This phenomenon, antigenic modulation (AMd), was tested on AChR of rat myotubes in serum from 48 myasthenic patients. Sixty-six percent of the sera increased AChR degradation. AMd activity was higher in more severely affected patients, paralleled clinical evolution in individual patients, and was related to AChR-antibody titer. Steroid treatment and thymectomy did not affect AMd activity. Patients who had a thymoma always had greater AMd activity.

Adolescent↗
PubMed2004

Expression systems for the production of recombinant pharmaceuticals.

The new generation of biological products are largely the result of genetic engineering. The qualitative and quantitative demand for recombinant proteins is steadily increasing. Molecular biologists are constantly challenged by the need to improve and optimise the existing expression systems, and also develop novel approaches to face the demands of producing the complex proteins of tomorrow. This continuous evolution is paralleled by growing concerns about the safety of these novel pharmaceuticals, with health authorities setting high standards for certification. One of the strategies used by researchers in this field involves sourcing new genetic elements for incorporation into expression systems by systematically analysing the rich natural diversity of microorganisms and plant-based expression systems. There are, in addition, numerous tools for modifying microorganisms and for re-engineering existing biological pathways or processes to meet the needs of the pharmaceutical industry. The aim of this review is to present the conventional and alternative expression systems, focusing on prokaryotic expression systems and briefly exploring other complementary recombinant protein production systems and their unique features.

Animals↗
PubMed2004

Harvey W. Cushing and cerebrovascular surgery: Part I, Aneurysms.

The development of surgical techniques for the treatment of intracranial aneurysms has paralleled the evolution of the specialty of neurological surgery. During the Cushing era, intracranial aneurysms were considered inoperable and only ligation of the carotid artery was performed. Cushing understood the limitations of this approach and advised the need for a more thorough understanding of aneurysm pathology before further consideration could be given to the surgical treatment of cerebral aneurysms. Despite his focus on brain tumors, Cushing's contributions to the discipline of neurovascular surgery are of great importance. With the assistance of Sir Charles Symonds, Cushing described the syndrome of subarachnoid hemorrhage. He considered inserting muscle strips into cerebral aneurysms to promote aneurysm sac thrombosis and designed the "silver clip," which was modified by McKenzie and later used by Dandy to clip the first intracranial aneurysm. Cushing was the first surgeon to wrap aneurysms in muscle fragments to prevent recurrent hemorrhage. He established the foundation on which pioneers such as Norman Dott and Walter Dandy launched the modern era of neurovascular surgery.

Adult↗
PubMed1991

Neurobiorheology. A new branch of biorheology. Historical background and current ideas.

The application of principles of biorheology, hemorheology and perihemorheology on problems of the nervous system in health and disease was suggested by Alfred L. Copley (1982, 1987). Late in 1988 Copley and Sourander considered neurobiorheology to be an appropriate term for a new branch of biorheology bridging the gap between biorheology and neurobiology. Neurobiorheology can be defined as a research field concerned with deformation behaviour of matter including flow and transportation in context with the structure and function of the nervous system at macroscopic, cellular, subcellular and molecular levels. It may be considered a basic life science with important clinical applications. Its "raison d'être" should be to apply various ways of thinking, calculations and techniques used in biorheology to treat and if possible to solve neurobiological problems. Many regionally different chemical, structural and functional properties characterize the developing and adult nervous system and those parts of the circulatory system ("vessel-blood organ") which penetrate the nervous system at all levels. Considering the close metabolic and functional relations between neurons and surrounding non-neuronal ectodermal cells, neuroglial and Schwann cells deriving from common precursor cells in the wall of the neural tube and neural crest respectively, the term neuroectodermal organ appears suitable. The almost parallel ontogenetic evolution of vessel-blood organ and neuroectodermal organ and their interaction during the entire individual life cycle constitutes a challenging stimulus for integrated research. The main purpose of this review is to give some examples of importance concerning still insufficiently elucidated neurobiological problems suitable for biorheological approaches. Particular attention will be paid to the microenvironment at central and peripheral levels of the neuroectodermal organ.

Animals↗
PubMedDate not supplied

Three years of "CASMS": the world's busiest medical simulation centre.

Medical simulation is a relatively new teaching modality suitable for medical education at all levels, although its long-term benefits have not yet been validated. Simulation allows the participant to practise diagnosis, medical management and behavioural approaches in the care of acutely ill patients in a controlled environment. Simulators have achieved widespread acceptance in the fields of anaesthesia, intensive care and emergency medicine. More recently, team training for pre-hospital and within-hospital multidisciplinary medical response teams has become popular. The increasing number and diversity of courses at "CASMS" parallels the evolution of simulation centres into regional clinical skills centres elsewhere. Such centres are likely to become a cost-effective means of achieving greater consistency in medical skill acquisition and may improve patient outcomes after medical crises.

Anesthesiology↗
PubMedDate not supplied

Neutralizing influenza antibodies, IgA and total protein in the nasopharyngeal secretions of subjects vaccinated by nasal route with the inactivated influenza vaccine prepared in the "Stefan S. Nicolau" Institute of Virology.

Intranasal administration of two doses of the inactivated influenza vaccine prepared in the "Stefan S. Nicolau" Institute of Virology was followed by rises in the level of neutralizing secretory influenza antibodies in 82% of the cases. The concomitant study of secretory antibody, IgA and total protein levels, as well as of the serum HAI influenza antibodies demonstrated that their evolution was parallel only in 23% of the vaccinees. The percentage of secretory antibody conversion was similar to the rate of protection conferred by the vaccine.

Administration, Intranasal↗
PubMed2002

[Contemporary university: a betrayed tradition?].

The current evolution of University is examined in parallel with the evolution of society. Society of uncertainty, crisis of the social actor, selective mechanisms of the elite, fundamental role of technical predominance and of economical processes are analyzed based on the "tradition" concept. The possibility of an authoritative comeback of the role of University is found in an active and articulated intervention of integration and cultural mediation, substantiating the bridge of tradition.

Cultural Characteristics↗
PubMed1992

Failla Memorial Lecture. From beans to genes--back to the future.

Developments in radiation biology have inevitably paralleled the evolution of systems and end points in the wider field of biology. I review the development of three areas that have interested me during the 35 years that I have been involved with radiation research. (1) The dose-rate effect. My first graduate student, Joel Bedford, and I demonstrated the dependence of mammalian cell killing on the dose rate at which gamma rays are delivered. These studies led to the recent development of pulsed low-dose-rate brachytherapy and the design of a new machine for clinical use. (2) Hypoxic radiosensitizers and bioreductive drugs. The hypothesis that the presence of foci of hypoxic cells in human tumors could limit their curability by gamma rays led to the development of nitromidazales that preferentially sensitize hypoxic cells. Our contributions included the observation that misonidazole was also cytotoxic to hypoxic cells, that sensitization was increased by prolonged preincubation, and that the mechanism involved depletion of thiols. More recently we have collaborated with Ged Adams and Bob Sutherland in the development of a new generation of hypoxic cell cytotoxins. In particular, we have been concerned with the assessment of oncogenicity in relation to drug structure. (3) Oncogenic transformation in vitro. The use of in vitro assays for oncogenic transformation has represented a major interest for this laboratory largely due to collaborations first with Carmia Borek, and more recently with Richard Miller and Tom Hei. We published the first dose-response curves for gamma rays, and more recently for a range of neutron energies and for charged particles of defined LET. Radiation-induced oncogenic transformation in C3H 10T1/2 cells has been shown to be due to a dominant acting transforming gene, which has been isolated and is in the process of being characterized and sequenced by Greg Freyer.

Animals↗
PubMedDate not supplied

Dynamics of the changes in the cerebral amounts of cyclic AMP and some prostaglandins during cobalt-60 gamma-radiation-induced brain edema.

The total amounts of cyclic AMP (cAMP), prostaglandin E1 (PGE1) and prostaglandin F2alpha (PGF2alpha) in cerebra have been measured in rats, at constant intervals, up to 18 days after whole body exposure to either a unique moderate dose (500 rads) or a unique lethal dose (750 rads) of cobalt-60 gamma-radiation. The experimental findings indicate that this radiation (i) results in an abrupt short-lasting increase in the amount of cerebral cAMP after a 500 rad-irradiation and a progressive long-lasting increase in its amount after a 750 rad-irradiation, and (ii) induces no change in the normally, existing correlation between cerebral PGE1 and cAMP, but affects deeply the normally existing correlation between cerebral PGF2alpha and cAMP. These biochemical alterations generally parallel the evolution of the radiation-induced brain edema.

Animals↗