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Daniel Drake Kathy Dutton Martha Engelke Maura McAuliffe Mary Ann Rose 《Surgery for obesity and related diseases》2005,1(5):462-466
BACKGROUND: Despite increasing numbers of morbidly obese patients admitted to acute care facilities for surgery or treatment of nonsurgical conditions, there is little evidence of the problems nurses face in providing care to these patients. Anecdotal evidence suggests that the care of these patients is more demanding than the care of nonobese patients. The objective of this study was to describe nurses' perceptions of the challenges that they face when caring for morbidly obese patients. METHODS: Focus groups of nurses from a tertiary care facility were convened. A trained facilitator posed questions to the group concerning various aspects of care for morbidly obese patients. Comments of respondents were categorized using NVIVO software. RESULTS: Nurses reported concerns about the increased staffing needs required for care of these patients and the particular challenges of the physical care. Concerns also included the availability, placement, and use of specialized equipment. Room size and the absence of some equipment were also problematic. Finally, nurses perceived safety issues, both for themselves and their patients. CONCLUSIONS: Morbidly obese patients in the acute care setting require specialized nursing care in terms of techniques, levels of staffing required, and the use of specialized equipment. 相似文献
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Maura Jones Moyle Susan Ellis Weismer Julia L Evans Mary J Lindstrom 《J. Speech Lang. Hear. Res.》2007,50(2):508-528
PURPOSE: This study examined the longitudinal relationships between lexical and grammatical development in typically developing (TD) and late-talking children for the purposes of testing the single-mechanism account of language acquisition and comparing the developmental trajectories of lexical and grammatical development in late-talking and TD children. METHOD: Participants included 30 children identified as late talkers (LTs) at 2;0 (years;months), and 30 TD children matched on age, nonverbal cognition, socioeconomic status, and gender. Data were collected at 5 points between 2;0 and 5;6. RESULTS: Cross-lagged correlational analyses indicated that TD children showed evidence of bidirectional bootstrapping between lexical and grammatical development between 2;0 and 3;6. Compared with the TD group, LTs exhibited less evidence of syntactic bootstrapping. Linear mixed-effects modeling of language sample data suggested that the relationship between lexical and grammatical growth was similar for the 2 groups. CONCLUSION: Lexical and grammatical development were strongly related in both groups, consistent with the single-mechanism account of language acquisition. The results were mixed in terms of finding longitudinal differences in lexical-grammatical relationships between the TD and late-talking children; however, several analyses suggested that for late-talking children, syntactic growth may be less facilitative of lexical development. 相似文献
5.
Human lymphoblastoid cells produce extracellular matrix-degrading enzymes and induce endothelial cell proliferation, migration, morphogenesis, and angiogenesis 总被引:11,自引:0,他引:11
A. Vacca D. Ribatti M. Iurlaro A. Albini M. Minischetti F. Bussolino A. Pellegrino R. Ria M. Rusnati M. Presta V. Vincenti M. G. Persico F. Dammacco 《International Journal of Clinical & Laboratory Research》1998,28(1):55-68
Human lymphoproliferative diseases can be hypothesized to invade locally and to metastatize via mechanisms similar to those
developed by a variety of solid tumors, i.e., the secretion of extracellular matrix-degrading enzymes and stimulation of angiogenesis.
To assess this hypothesis, Namalwa, Raji, and Daudi cell lines (Burkitt’s lymphoma), LIK and SB cell lines (B-cell lymphoblastic
leukemia), CEM and Jurkat cell lines (T-cell lymphoblastic leukemia), and U266 cell line (multiple myeloma) were evaluated
for their capacity to produce matrix metalloproteinase-2 and -9, and urokinase-type plasminogen activator. These cell lines
were also assessed for their ability: (1) to produce the angiogenic basic fibroblast growth factor and vascular endothelial
growth factor; (2) to induce an angiogenic phenotype in cultured endothelial cells, represented by cell proliferation, chemotaxis,
and morphogensis; (3) to stimulate angiogenesis in different in vivo experimental models. All cell lines expressed the mRNA
for one or both metalloproteinases. Namalwa, Raji, LIK, SB, and U266 cells secreted the active form of both metalloproteinases,
while Daudi, CEM, and Jurkat cells produced metalloproteinase-2 but not -9. In contrast, urokinase-type plasminogen activator
was secreted only by SB cells. While Raji, LIK, SB, CEM, and Jurkat cells secreted both basic fibroblast growth factor and
vascular endothelial growth factor, Daudi and U266 cells produced only the former, and Namalwa cells only the latter. Accordingly,
the conditioned medium of all cell lines stimulated cell proliferation and/or chemotaxis in cultured endothelial cells, with
the exception of that of Namalwa cells which was ineffective. The conditioned medium of CEM and Jurkat cells induced morphogenesis
in cultured endothelial cells grown on a reconstituted basement membrane (Matrigel). Lastly, Namalwa, Raji, LIK, SB, U266,
CEM, and Jurkat cells induced angiogenesis and mononuclear cell recruitment in the murine Matrigel sponge model and in a chick
embryo chorioallantoic membrane assay. The extent of angiogenesis in both models was strictly correlated with the density
of the mononuclear cell infiltrate. The results indicate that human lymphoproliferative disease cells possess both local and
remote invasive ability via the secretion of matrix-degrading enzymes and the induction of angiogenesis which is fostered
by host inflammatory cells and by an intervening ensemble of angiogenic factors. 相似文献
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7.
New Insights into the Pathogenesis and the Therapy of Recurrent Focal Glomerulosclerosis 总被引:4,自引:0,他引:4
Recurrent focal glomerulosclerosis (FSGS) in renal allografts has remained a frustrating and enigmatic disease. Recent studies on gene mutations encoding podocin and other components of the slit-diaphragm in patients with native kidney nephrotic syndrome have underscored the heterogenecity of the idiopathic form of FSGS. While familial FSGS rarely recurs following transplantation, the sporadic variety of FSGS is associated with a 30% recurrence rate. The patients with the sporadic variety of FSGS who have homozygous or complex heterozygous podocin mutations have a low recurrence rate. In the other patients with sporadic FSGS, a more complex and likely multifactorial etiology accounts for the recurrence of FSGS. The role of CD80 expression on podocytes is intriguing but requires confirmation in kidney biopsies of patients with recurrent FSGS. Recent findings on podocin genomics, the permeability factor and CD80 expression may ultimately lead to a better understanding of recurrent FSGS as well as a more effective approach to its prevention and treatment. 相似文献
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Jordi Ortiz Lawrence W. Fitzgerald Maura Charlton Sarah Lane Louis Trevisan Xavier Guitart William Shoemaker Ronald S. Duman Eric J. Nestler 《Synapse (New York, N.Y.)》1995,21(4):289-298
In previous studies, we have demonstrated that chronic administration of morphine or cocaine produces some common biochemical adaptations in the ventral tegmental area (VTA) and nucleus accumbens (NAc), components of the mesolimbic dopamine system implicated in the reinforcing actions of these and other drugs of abuse. Since this neural pathway is also implicated in the reinforcing actions of ethanol, it was of interest to determine whether chronic ethanol exposure results in similar biochemical adaptations. Indeed, as seen for chronic morphine and cocaine treatments, we show here that chronic ethanol treatment increased levels of tyrosine hydroxylase and glial fibrillary acidic protein immunoreactivity, and decreases levels of neurofilament protein immunoreactivity, in the VTA. Also like morphine and cocaine, ethanol increases levels of cyclic AMP-dependent protein kinase activity in the NAc. These actions of ethanol required long-term exposure to the drug, and were in most cases not seen in the substantia nigra or caudate-putamen, components of the nigrostriatal dopamine system studied for comparison. Altered levels of tyrosine hydroxylase in catecholaminergic cells frequently reflect altered states of activation of the cells. Moreover, increasing evidence indicates that ethanol produces many of its acute effects on the brain by regulating NMDA glutamate and GABA receptors. We therefore examined the influence of chronic ethanol treatment on levels of expression of specific glutamate and GABA receptor subunits in the VTA. It was found that long-term, but not short-term, ethanol exposure increased levels of immunoreactivity of the NMDARl subunit, an obligatory component of NMDA glutamate receptors, and of the Glu Rl subunit, a component of many AMPA glutamate receptors; but at the same time, long-term ethanol exposure decreased immunoreactivity levels of the α1 subunit of the GABAA receptor complex. These changes are consistent with an increased state of activation of VTA neurons inferred from the observed increase intyrosine hydroxylase (TH) expression. These results demonstrate that chronic ethanol exposure results in several biochemical adaptations in the mesolimbic dopamine system, which may underlie prominent changes in the structural and functional properties of this neural pathway related to alcohol abuse and alcoholism. © 1995 Wiley-Liss, Inc. 相似文献
10.
María De Los Ángeles Monclus Andreína Cesari María Eugenia Cabrillana Paola Vanina Borelli Amanda Edith Vincenti Mario Héctor Burgos Miguel Walter Fornés 《Anatomical record (Hoboken, N.J. : 2007)》2007,290(7):814-824
In many mammals, sperm associations had been observed, but not in the mouse. In this work, mouse sperm rosettes are morphologically described inside the epididymis and during its dissolution in a culture medium. Also characterized are the saccharides present in the linking material. Sperm association and other epididymal actions are supported by sperm during epididymal transit and are verified at the caudal region, suggesting a relation between epididymal transit and sperm maturation. In drops of epididymal content obtained from distal (cauda), but not from proximal (caput and corpus) regions; dissolved in culture medium, rosettes appear to be 10 to 15 motile sperm joined by their heads. After 3 min, sperm progressively detach, disassembling the rosette. These structures are studied by several techniques, including optic, electronic (scanning electron microscopy and transmission electron microscopy), and video microscopy. At the ultrastructural level, a dense network of electron‐dense material was observed between sperm heads, joining them. Based on previous works in rat, several lectins were used to characterize the type of saccharides present in this linking material. To avoid the contact between sperm and epididymal fluid from distal region—that probably exerts an influence on sperm association—a ligature was placed between caput and corpus. This epididymal content isolated from caput did not display any rosettes after 28 days. Anat Rec, 2007. © 2007 Wiley‐Liss, Inc. 相似文献