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71.
72.
EM Bevis 《Canadian Metallurgical Quarterly》1993,24(4):56-61
As the whole context of nursing continues to change radically in the face of unmet societal needs, nothing short of total revolution will suffice. Nurses must take control of nursing practice and be critical of the nation's inadequate "sick-care" system in order to effect sweeping changes in the scope, availability and efficacy of healthcare in the U.S. To do this requires an acknowledgment that true nursing education cannot exist without nursing practice. The transformation of curriculum must center on caring, which characterizes what nurses really do in a medically dominated system focused exclusively on curing. 相似文献
73.
An unusual clinical variant of porokeratosis (Mibelli's disease) appeared in a patient soon after birth; the lesions were widely distributed mostly on the right half of the body. Spontaneous recurrent ulcerations occurred over certain sites. The right foot was grossly deformed as a result of atrophic scarring after ulcerations. Biopsy specimens of the classical lesion showed cornoid lamella. It is suggested that the term "ulcerative systematized porokeratosis" be used to describe this clinical variant of porokeratosis. 相似文献
74.
Sung Wook Hwang Jin Kie Shim Susan EM Selke Herlinda Soto‐Valdez Laurent Matuana Maria Rubino Rafael Auras 《Polymer International》2012,61(3):418-425
Poly(L ‐lactic acid) (PLLA) films containing various concentrations of two natural antioxidants, α‐tocopherol and resveratrol, were fabricated by a melt compounding and compression molding process. The influence of the antioxidants on the optical properties such as color and UV‐visible light transmission was analyzed. The thermal, mechanical, rheological and physical properties of PLLA films with added antioxidants were assessed. PLLA films with added α‐tocopherol and resveratrol showed a yellowish brown color and the lightness was influenced by the presence of the antioxidants. The glass transition and melting temperatures were significantly reduced with the addition of antioxidants while enhanced thermal stability was observed, which could be a benefit and important for processing and production. PLLA films with added antioxidants were slightly more hydrophobic than neat PLLA. The combination effect of plasticizing and enhancement of the elastic modulus with differing concentrations of two antioxidants played a critical role in the mechanical and thermomechanical properties of PLLA films. The melt viscosity of the PLLA films with added antioxidants was substantially higher than that of neat PLLA. The higher melt viscosity and G′(ω) could be an indication of formation of entanglement between PLLA and the two antioxidants. Copyright © 2012 Society of Chemical Industry 相似文献
75.
M Dong XQ Ding DI Pinon EM Hadac RP Oda JP Landers LJ Miller 《Canadian Metallurgical Quarterly》1999,274(8):4778-4785
The molecular basis of ligand binding to receptors provides important insights for drug development. Here, we explore domains of the cholecystokinin (CCK) receptor that are critical for ligand binding, using a novel series of fluorescent photolabile probes, receptor proteolysis, and rapid high resolution separation of peptide fragments by capillary electrophoresis. Each probe incorporated the same fluorophore and a photolabile p-benzoylphenylalanine at the amino terminus of the pharmacophoric domain (residue 24 of CCK-33) of CCK analogues representing full agonist, partial agonist, and antagonist of this receptor. Each was used to label the CCK receptor expressed on Chinese hamster ovary-CCKR cells, with the labeled domain then released by cyanogen bromide cleavage. Capillary electrophoresis with laser-induced fluorescence detection achieved an on-capillary mass sensitivity of 1.6 attomoles (10(-18) mol), with an excellent signal-to-noise ratio. Each of the biologically divergent, but structurally similar probes saturably and specifically labeled the same receptor domain, consistent with conservation of "docking" determinants. This had an apparent mass of 2.9 kDa, most consistent with the first extracellular loop domain. An additional probe having its site of covalent attachment in a different region of the probe (residue 29 of CCK-33) labeled a distinct receptor fragment with differential migration on capillary electrophoresis (third extracellular loop). Identification of the specific receptor residue(s) covalently linked to the amino-terminal probes must await further fragmentation and sequence analysis. 相似文献
76.
VL Cressman EM Hicks WK Funkhouser DC Backlund BH Koller 《Canadian Metallurgical Quarterly》1998,19(6):853-866
In the cystic fibrosis (CF) patient, lung function decreases throughout life as a result of continuous cycles of infection, particularly with Pseudomonas aeruginosa and Staphylococcus aureus. The mechanism underlying the pathophysiology of the disease in humans has not been established. However, it has been suggested that abnormal, tenacious mucus, resulting perhaps from improper hydration from loss of Cl- secretion via the cystic fibrosis transmembrane conductance regulator (CFTR) protein, impairs clearance of bacteria from the CF airway and provides an environment favorable to bacterial growth. If this hypothesis is correct, it could explain the absence of respiratory disease in CFTR-deficient mice, since mice have only a single submucosal gland and display few goblet cells in their lower airways, even when exposed to bacteria. To test this hypothesis further, we induced allergic airway disease in CFTR-deficient mice. We found that induction of allergic airway disease in mice, unlike bacterial infection, results in an inflammatory response characterized by goblet cell hyperplasia, increased mucin gene expression, and increased production of mucus. However, we also found that disease progression and resolution is identical in Cftr-/- mice and control animals. Furthermore, we show that the presence of mucus in the Cftr-/- airway does not lead to chronic airway disease, even upon direct inoculation with S. aureus and P. aeruginosa. Therefore, factors in addition to the absence of high levels of mucus secretion protect the mouse from the airway disease seen in human CF patients. 相似文献
77.
Refusal to eat by the elderly, and subsequent malnutrition, occurs in both institutional and community settings. Causes include physiologic changes associated with aging, mental disorders such as dementia and depression, and medical, social, and environmental factors. Treatment approaches call for management of these causes while considering the roles that medicine, ethics, and culture play in the process. 相似文献
78.
EM Burtsev LA Zhdanova TV Riabchikova EV Batanova NB Fokina GN Gromtseva 《Canadian Metallurgical Quarterly》1998,98(9):9-11
90 infants with intrauterine growth retardation (IGR) and 100 normal infants (control group) were followed up from 5 days till 3 years of life. In IGR infants there was a more frequent combination of several neurologic syndromes, an early manifestation of motor disorders (from the very moment of birth), a delay of neuro-psychic development (during the first year of life), a tendency to development of moderate hydrocephalus by the age of 6 months. Autonomic-visceral disorders in them were mostly characterized by the symptoms of abaissement, but not of irritation. 相似文献
79.
DJ Birnbach DJ Stein O Murray DM Thys EM Sordillo 《Canadian Metallurgical Quarterly》1998,88(3):668-672
OBJECTIVE: The clinical, mammographic and low grade cytologic features of mucinous carcinoma can make it difficult to diagnose by fine needle aspiration (FNA). Fine needle aspirates of mucinous carcinoma were reviewed with the mammographic findings to improve the diagnostic criteria and specificity for FNA. STUDY DESIGN: All aspirates were reviewed for cytologic criteria and cellularity, atypia and single epithelial cells (SEC). A nuclear grade was assigned to each aspirate. The mammographic findings were correlated with the FNA diagnoses. RESULTS: Forty-five patients with an aspirate and confirmed diagnosis of mucinous carcinoma were identified. The clinical impressions were: benign tissue (5), fibroadenoma (6) and cancer (32). The initial cytologic diagnoses were: adenocarcinoma (32), atypical/suspicious for cancer (11), insufficient (1) and negative (1). The cytologic findings showed smears with increased cellularity (35/45 cases) and minimal atypia. SEC with eccentrically located nuclei and eosinophilic cytoplasm were numerous. The assigned nuclear grade was as follows: grade 1, 16 cases; grade 2, 20 cases; and grade 3, 6 cases. Abundant mucin was present in Papanicolaou-stained slides in 23 cases; focal mucin was observed in 14 cases. The mammograms showed a smoothly outlined to lobulated mass with only slight irregularities identified. CONCLUSION: Mucinous carcinoma has a cytologic pattern that includes increased cellularity, with numerous single cells and abundant mucin. Although the mammographic findings may mimic a benign lesion, in the most patients a specific diagnosis of mucinous carcinoma can be made by FNA. 相似文献
80.
A Martin M State K Koenig R Schultz EM Dykens SB Cassidy JF Leckman 《Canadian Metallurgical Quarterly》1998,155(9):1265-1273