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71.
We examined the literature relating to the safe care of acutely ill hospitalized patients, and found that there are substantial opportunities for improvement. Recent research suggests substantial benefit may be obtained by systems of outreach care that facilitate better integration, co-ordination, collaboration and continuity of multidisciplinary care. Herein we review the various approaches that are being adopted, and suggest the need for continuing evaluation of these systems as they are introduced into different health care systems.  相似文献   
72.
The aim of this study was to evaluate the in vivo biodegradation and biocompatibility of three-dimensional (3D) scaffolds based on a hydroxyl-functionalized polyester (poly(hydroxymethylglycolide-co-ε-caprolactone), PHMGCL), which has enhanced hydrophilicity, increased degradation rate, and improved cell-material interactions as compared to its counterpart poly(ε-caprolactone), PCL. In this study, 3D scaffolds based on this polymer (PHMGCL, HMG:CL 8:92) were prepared by means of fiber deposition (melt-plotting). The biodegradation and tissue biocompatibility of PHMGCL and PCL scaffolds after subcutaneous implantation in Balb/c mice were investigated. At 4 and 12 weeks post implantation, the scaffolds were retrieved and evaluated for extent of degradation by measuring the residual weight of the scaffolds, thermal properties (DSC), and morphology (SEM) whereas the polymer was analyzed for both its composition ((1)H NMR) and molecular weight (GPC). The scaffolds with infiltrated tissues were harvested, fixed, stained and histologically analyzed. The in vitro enzymatic degradation of these scaffolds was also investigated in lipase solutions. It was shown that PHMGCL 3D-scaffolds lost more than 60% of their weight within 3 months of implantation while PCL scaffolds showed no weight loss in this time frame. The molecular weight (M(w)) of PHMGCL decreased from 46.9 kDa before implantation to 23.2 kDa after 3 months of implantation, while the molecular weight of PCL was unchanged in this period. (1)H NMR analysis showed that the degradation of PHMGCL was characterized by a loss of HMG units. In vitro enzymatic degradation showed that PHMGCL scaffolds were degraded within 50 h, while the degradation time for PCL scaffolds of similar structure was 72 h. A normal foreign body response to both scaffold types characterized by the presence of macrophages, lymphocytes, and fibrosis was observed with a more rapid onset in PHMGCL scaffolds. The extent of tissue-scaffold interactions as well as vascularization was shown to be higher for PHMGCL scaffolds compared to PCL ones. Therefore, the fast degradable PHMGCL which showed good biocompatibility is a promising biomaterial for tissue engineering applications.  相似文献   
73.
Altered glutamate transmission in the striatum has been proposed to play a critical role in the pathophysiology of Huntington's disease (HD), a genetic disorder associated with impaired activity of the mitochondrial complex II (succinate dehydrogenase, SD). In the present study, we recorded spontaneous (sEPSCs) and miniature excitatory postsynaptic currents (mEPSCs) from striatal neurons of both toxic (systemic administration of 3-nitropropionic acid in rats) and genetic models of HD (R6/2 transgenic mice). In both models, we found a significant down-regulation of glutamate transmission, suggesting that reduced synaptic excitation of the input structure of the basal ganglia represents a physiological correlate of HD.  相似文献   
74.
OBJECTIVES: The aim of the study was to assess the clinical significance of intra-uterine fluid collection in postmenopausal women with cervical stenosis with and without vaginal bleeding. METHODS: A group of 82 consecutive postmenopausal women with cervical stenosis and sonographically confirmed intra-uterine fluid collection underwent D&C with or without hysteroscopy. Diagnostic hysteroscopy was performed in all patients with an endometrial thickness (ET) was greater than 8mm, or with irregular endometrium at any degree of ET. The patients were divided and evaluated prospectively into two groups according to the presence or absence of postmenopausal bleeding (PMB). Twenty-six women were with PMB and 56 women were asymptomatic. RESULTS: The groups were similar as far as endometrial thickness and histopathological results were concerned. Atrophic endometrium was found in 69 patients (84%), 23 in the PMB group (89%) and 46 in the other group (82%), proliferative endometrium in 7 (9%) and endometrial polyps were found in 35 patients (43%), 12 in the PMB group (46%) and 23 in the other group (41%). When ET was > or =8 mm, in 93% of the cases an endometrial polyp was found (25 out of 27). No case of endometrial cancer was found. A premalignant condition was diagnosed in one patient with an endometrial polyp in the PMB group. All patients with endometrial thickness of less than 3 mm in ultrasound had atrophic endometrium. The incidence of intrauterine pathology increased with the increasing thickness of endometrium as observed by ultrasound. CONCLUSIONS: The presence of intra-uterine fluid collection in postmenopausal patients with cervical stenosis seems to be a benign condition. Normal endometrium of less than 3mm observed by ultrasound in postmenopausal women without vaginal bleeding does not necessarily need further surgical investigation.  相似文献   
75.
Despite the increasingly dangerous world where trauma and loss are common, relatively few studies have explored traumatic grief in children. The 1998 American Embassy bombing in Nairobi, Kenya, provided an unfortunate opportunity to examine this topic. This report describes findings in 156 children who knew someone killed in the incident, assessed 8 to 14 months after the explosion. Bomb-related posttraumatic stress was associated with physical exposure, acute response, posttraumatic stress related to other negative life events, type of bomb-related loss, and subsequent loss. Grief was associated with bomb-related posttraumatic stress, posttraumatic stress related to other negative life events, and type of bomb-related loss. The study supports the developing literature on traumatic grief and the need for studies exploring the potentially unique aspects of this construct.  相似文献   
76.
Classifying human beings according to race and ethnicity may seem straightforward to some but it, in fact, belies a difficult process. No standard procedure exists for categorizing according to race and ethnicity, calling into question the variables' use in research. This article explores the use of race and ethnicity variables in the nursing research literature. Content analysis was conducted of a sample of 337 original research studies published in Nursing Research from the years 1952, 1955, and then every 5 years through to 2000. Of the 337 research articles reviewed, 167 mentioned race, ethnicity, or their 81 code words or phrases. Out of the 167 articles, 153 used race or ethnicity to describe the study sample, and 45 of the 167 articles included race or ethnicity as an element of data analysis. Throughout the sample, there was substantial inconsistency related to race and ethnicity categorization, meanings of the terms, and use of these variables. Specificity related to conceptual assumptions, definitions, and context was missing and, as a result, data interpretation and understanding are suspect. The integrity of nursing knowledge requires that nurse researchers recognize and address the difficulties inherent in using race and ethnicity in health research.  相似文献   
77.
DJ-1 plays an important role in oxidative stress, and is involved in various neurodegenerative diseases. Accumulating evidence suggests a central role for oxidative stress in multiple sclerosis (MS). The aim of this study was to examine whether changes occur in DJ-1 expression in an animal model of MS, experimental autoimmune encephalomyelitis (EAE). We found upregulation of DJ-1 mRNA and protein expression levels in EAE and a correlation between disease severity and increased DJ-1 levels. Although DJ-1 isoforms were more alkaline in controls, in EAE, a shift was noted toward acidic isoforms. ROS induced by SIN-I exposure led to an increase in DJ-1 mRNA and protein levels in human glioma U-87 cells. Immunocytochemical staining demonstrated that DJ-1 is present both in the cytoplasm and the nuclei of these cells. This is the first report of modulation of DJ-1 expression in EAE. Upregulation of DJ-1 was noted in EAE, and similar results were observed in glioma cells exposed to ROS. In view of the accumulating evidence on the central role of oxidative stress in MS, and the importance of DJ-1 in oxidative stress management by the CNS, we believe that DJ-1 will be found to have a central role in MS.  相似文献   
78.
79.
After our initial discovery of under expression of the GABA(A) receptor delta subunit in a genome wide screening for differentially expressed mRNAs in brain of fragile X mice, a validated model for fragile X mental retardation syndrome, we analyzed expression of the 17 remaining subunits of the GABA(A) receptor using real-time PCR. We confirmed nearly 50% under expression of the delta subunit and found a significant 35%-50% reduction in expression of 7 additional subunit mRNAs, namely alpha(1), alpha(3), and alpha(4), beta(1) and beta(2) and gamma(1) and gamma(2), in fragile X mice compared to wild-type littermates. In concordance with previous results, under expression was found in cortex, but not in cerebellum. Moreover, decreased expression of specific GABA(A) receptor subunits in fragile X syndrome seems to be an evolutionary conserved hallmark since in the fragile X fly (Drosophila melanogaster) model we also found almost 50% under expression of all 3 subunits which make up the invertebrate GABA receptor, namely Grd, Rdl and Lcch3. In addition, we demonstrated a direct correlation between the amount of dFmrp and the expression of the GABA receptor subunits Rdl and Grd. Our results add evidence to previous observations of an altered GABAergic system in fragile X syndrome. Because GABA(A) receptors are the major inhibitory receptors in brain, involved in anxiety, depression, insomnia, learning and memory and epilepsy, processes also disturbed in fragile X patients, the well described GABA(A) receptor pharmacology might open new powerful opportunities for treatment of the behavioral and epileptic phenotype associated with fragile X syndrome.  相似文献   
80.
The influence of differentiation medium (DM) components on C2C12 murine myoblast differentiation has only been studied in monolayer cultures. Serum-free formulations have been applied that omit the use of sera with unknown composition. The goal of the present study was to compare the influence of serum-free media on C2C12 differentiation in 3-dimensional tissue-engineered muscle constructs. Myoblast proliferation and differentiation in media containing Ultroser G (DMU), insulin-like growth factor (IGF)-I (DMI), or both (DMUI) were compared with those induced by more-traditional media containing horse serum (HS) or horse serum and IGF-I (HSI). Effects of the applied media were assessed from gross construct morphology, total protein content, creatine kinase activity, and tissue viability. Addition of IGF-I (HSI) to the standard DM (HS) improved myoblast differentiation in muscle constructs. Even better results were obtained using DMU and DMUI culture conditions. DMI could not induce differentiation or maintain cell viability. Serum-free culture medium supplemented with DMU or DMUI accelerates and improves myoblast differentiation in engineered muscle tissue better than the gold standard HS.  相似文献   
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