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161.
Oral motor dysfunction is common in children with neurological impairment. Nutritional advice depends upon an accurate assessment of feeding potential in these cases. Videofluoroscopic assessment of oral motor function has been the accepted "gold standard" investigation for several years but has significant drawbacks, including the time constraints set by the use of ionizing radiation and the problems posed by the cumbersome equipment needed in mimicking the child's normal feeding situation. Ultrasonography (US) has been suggested as an alternative or additional investigation of oral motor function in children with neurological impairment. We prospectively evaluated a scoring system derived from US assessment of oral motor function in 32 malnourished disabled children with feeding problems by comparing them with a group of matched control children without neurological impairment. US imaging provided useful information with regard to the oral cavity and the soft tissue structures, capturing the salient features of tongue/hyoid/palate activity and bolus transport across the tongue and through the hypopharyngeal area. The mean percentage score obtained by US assessment of oral motor function in children with neurological impairment was 54.3 +/- 23.2 and from children without neurological impairment 91.9 +/- 12.7 (p < 0.0001). Scores for the oral and pharyngeal phases of swallowing were also very significantly lower than that in the control group, both phases being equally impaired in the disabled children. This study has demonstrated that a scoring system based on US assessment of different components of oral motor activity detects statistically significant differences in the feeding capabilities of children with neurological impairment. 相似文献
162.
DB Matchar EZ Oddone DC McCrory LB Goldstein PB Landsman G Samsa RH Brook C Kamberg L Hilborne L Leape R Horner 《Canadian Metallurgical Quarterly》1997,32(3):325-342
OBJECTIVE: To examine specifically the influence of estimated perioperative mortality and stroke rate on the assessment of appropriateness of carotid endarterectomy. DATA SOURCES/STUDY SETTING: An expert panel convened to rate the appropriateness of a variety of potential indications for carotid endarterectomy based on various rates of perioperative complications. We then applied these ratings to the charts of 1,160 randomly selected patients who had carotid endarterectomy in one of the 12 participating academic medical centers. STUDY DESIGN: An expert panel evaluated indications for carotid endarterectomy using the modified Delphi approach. Charts of patients who received surgery were abstracted, and clinical indications for the procedure as well as perioperative complications were recorded. To examine the impact of surgical risk assessment on the rates of appropriateness, three different definitions of risk strata for combined perioperative death or stroke were used: Definition A, low risk < 3 percent; Definition B, low risk < 5 percent; and Definition C, low risk < 7 percent. PRINCIPAL FINDINGS: Overall hospital-specific mortality ranged from 0 percent to 4.0 percent and major complications, defined as death, stroke, intracranial hemorrhage, or myocardial infarction, varied from 2.0 percent to 11.1 percent. Most patients (72 percent) had surgery for transient ischemic attack or stroke; 24 percent of patients were asymptomatic. Most patients (82 percent) had surgery on the side of a high-grade stenosis (70-99 percent). When the thresholds for operative risk were placed at the values defined by the expert panel (Definition A), only 33.5 percent of 1,160 procedures were classified as "appropriate." When the definition of low risk was shifted upward, the proportion of cases categorized as appropriate increased to 58 percent and 81.5 percent for Definitions B and C, respectively. CONCLUSIONS: Despite the high proportion of procedures performed for symptomatic patients with a high degree of ipsilateral extracranial carotid artery stenosis and generally low rates of surgical complications at the participating institutions, the overall rate of "appropriateness" using a perioperative complication rate of < 3 percent was low. However, the rate of "appropriateness" was extremely sensitive to judgments about a single clinical feature, surgical risk. These data show that before applying such "appropriateness" ratings, it is crucial to perform sensitivity analyses in order to assess the stability of the results. Results that are robust to moderate in variation in surgical risk provide a much sounder basis for policy making than those that are not. 相似文献
163.
RGH-2716 is a novel 1-oxa-3,8-diazaspiro[4.5] decan 2-one, which was published to have potent inhibitory effect on neuronal Na and Ca movement and stimulatory action on nerve growth factor (NGF)-production, as well as to show significant antiamnesic activity in experimental amnesia models. The aim of the present experiments was to study the effect of the compound on the learning process and on the different stages of memory using water-labyrinth in normal and memory impaired young animals, as well as to study cognitive effect of RGH-2716 on aged animals. At the doses of 0.5 mg/kg i.p. or 3 mg/kg p.o. given before daily swimming, this compound improved the learning process of young animals impaired by either diazepam (DIA) or scopolamine (SCOP). In retrograde amnesia model RGH-2716 (3 mg/kg p.o.) significantly ameliorated consolidation process and retrieval of information impaired by SCOP or DIA. Nimodipine and vinpocetine (10 mg/kg p.o.) showed moderate effect compared to RGH-2716. Aged rats pretreated with daily i.p. RGH-2716 performed the tasks with significantly fewer errors and shorter swimming time than untreated aged rats. When aged animals had to solve a new labyrinth problem, treated aged rats showed significantly better learning ability than aged controls. One month of oral treatment of aged rats with 3 mg/kg dose of RGH-2716 two times daily resulted in a "tendency-like" improvement in learning of aged Fischer 344 and spontaneously hypertensive (SH) rats. The present results make RGH-2716 an interesting compound for the treatment of cognitive disorders. 相似文献
164.
F Song K Ito TL Denning D Kuninger J Papaconstantinou W Gourley G Klimpel E Balish J Hokanson PB Ernst 《Canadian Metallurgical Quarterly》1999,162(4):2275-2280
IL-10 plays an important role in preventing excessive inflammation to the normal flora in the intestinal lumen. The purpose of this study was to compare the effect of normal flora on inflammation in mice in which the IL-10 gene was disrupted. IL-10 knock-out mice housed in germfree conditions remained healthy while those housed in conventional conditions developed colitis after weaning, suggesting that IL-10 inhibits the adverse responses to luminal Ag. Crypt abscesses were present in virtually all of the diseased animals as evidenced by flattening of the epithelial cells and a large number of neutrophils in the lumen of the crypt. Since KC is a chemokine that is capable of recruiting neutrophils in mice, mRNA and protein for KC was measured. Increased levels of both KC mRNA and protein were detected in the colon of diseased mice. To determine whether the epithelial cells were capable of synthesizing KC and contributing to neutrophil accumulation in the crypts, a murine intestinal epithelial cell line (Mode-K) was shown to express mRNA and protein for KC. Two cytokines induced in association with colitis in these mice, TNF-alpha and IFN-gamma, increased the expression of KC mRNA and protein in murine epithelial cells. However, IL-10 was incapable of decreasing the induction of KC, even though the cells expressed the IL-10 receptor. These results suggest that the neutrophil chemokine KC is produced by gastrointestinal epithelial cells in response to inflammatory mediators that are expressed following exposure to normal flora in animals lacking IL-10. 相似文献
165.
Hair, muscle, and liver mercury concentrations were determined in river otter (Lutra canadensis) carcasses collected from the lower coastal plain and piedmont of Georgia. Mean muscle and hair mercury concentrations were greater (P < 0.001) in otters from the lower coastal plain (4.42 and 24.25 mg/kg wet wt, respectively) compared to otters from the piedmont (1.48 and 15.24 mg/kg, respectively). Liver tissue from lower coastal plain otters averaged 7.53 mg/kg mercury. Mean fetus brain and muscle mercury concentrations were 1.03 and 1.58 mg/kg wet wt, respectively, and fetal muscle mercury concentrations were correlated (r = 0.92) with maternal muscle mercury concentrations. Comparison of mercury concentrations found in Georgia otters to those associated with adverse effects in otter and mink (Mustela vison), indicate sublethal contamination with concentrations in some individuals approaching that observed in experimentally dosed individuals that developed clinical signs of mercurialism. Mercury concentrations in fish from the lower coastal plain approached or exceeded concentrations demonstrated to be toxic to experimentally dosed otters. 相似文献
166.
PB Francioli 《Canadian Metallurgical Quarterly》1993,7(1):97-115
There are a total of 8000 cases of infective endocarditis yearly in the United States. Central nervous system metastatic infections are not uncommon in infective endocarditis. Because ceftriaxone is highly bound to serum proteins, there is concern that the drug is highly bound to serum proteins, there is concern that the drug might not penetrate well in the core of an infected vegetation. To date, there are two published studies on the treatment of nonenterococcal streptococcal endocarditis by ceftriaxone in humans. Ceftriaxone appears to be an attractive alternative antibiotic therapy to conventional regimens in the treatment of streptococcal endocarditis. 相似文献
167.
Different classes of tryptophan residues in sarcoplasmic reticulum calcium-ATPase were investigated with respect to their exposure to quenchers and sensitivity to high-affinity calcium binding to the ATPase. The charged quenchers, iodide and cesium, produced only slight quenching of ATPase fluorescence, whereas noncharged acrylamide and notably oxygen produced significant quenching. This finding gives support to the proposed location of most of the tryptophan residues of the ATPase in transmembrane domains of this protein (MacLennan et al., 1985, Nature 316r, 696-700). Among the different quenchers tested, oxygen quenching alone was sensitive to calcium binding to the ATPase, indicating that oxygen quenched tryptophan residues located in regions of the ATPase molecule which undergo conformational changes upon calcium binding. Time-resolved oxygen quenching data were analyzed with a recently described model that takes into account the existence of two different classes of emitters in the ATPase (Ferreira and Verjovski-Almeida, 1991, J. Lumin. 48, 430-434): a short-lived blue-shifted exponential component plus a long-lived red-shifted continuous lifetime distribution. Oxygen quenching of the single-exponential lifetime component was found to be insensitive to calcium, whereas quenching of the distributed lifetime component was significantly (ca 25%) enhanced by calcium binding. The different sensitivities of the two tryptophan classes to calcium binding to the ATPase are interpreted in terms of the proposed location of tryptophan residues in relation to the calcium transport sites in the ATPase molecule. 相似文献
168.
169.
PB Carrieri V Provitera R Bruno M Perrella G Tartaglia A Busto O Perrella 《Canadian Metallurgical Quarterly》1997,19(6):599-600
Cerebrospinal fluid (CSF) and serum levels of transforming growth factor (TGF)-beta and soluble intercellular adhesion molecule-1 (sICAM-1) were evaluated in ten patients with definite multiple sclerosis (MS) of the relapsing-remitting type. CSF TGF-beta levels of MS patients in remission were significantly (p < 0.01) higher than of MS patients in active phase, and there was a significant inverse correlation (p < 0.05) between TGF-beta and slCAM-1 levels in the CSF of patients in both remitting and relapsing type. This is consistent with a possible down-regulation of TGF-beta on ICAM-1 expression and suggests a possible synthesis in the central nervous system of TGF-beta. 相似文献
170.
N Baumgartner PB Dobrin M Morasch QS Dong R Mrkvicka 《Canadian Metallurgical Quarterly》1996,111(5):1063-1072
Experiments were performed in dogs to evaluate the mechanics of 26 end-to-end and 42 end-to-side artery-vein graft anastomoses constructed with continuous polypropylene sutures (Surgilene; Davis & Geck, Division of American Cyanamid Co., Danbury, Conn.), continuous polybutester sutures (Novafil; Davis & Geck), and interrupted stitches with either suture material. After construction, the grafts and adjoining arteries were excised, mounted in vitro at in situ length, filled with a dilute barium sulfate suspension, and pressurized in 25 mm Hg steps up to 200 mm Hg. Radiographs were obtained at each pressure. The computed cross-sectional areas of the anastomoses were compared with those of the native arteries at corresponding pressures. Results showed that for the end-to-end anastomoses at 100 mm Hg the cross-sectional areas of the continuous Surgilene anastomoses were 70% of the native artery cross-sectional areas, the cross-sectional areas of the continuous Novafil anastomoses were 90% of the native artery cross-sectional areas, and the cross-sectional areas of the interrupted anastomoses were 107% of the native artery cross-sectional areas (p < 0.05). At physiologic pressures, there were no differences in compliance among the three types of anastomosis. These data suggest that when constructing an end-to-end anastomosis in a small vessel, one should use an interrupted suture line or possibly continuous polybutester suture. Forty-two end-to-side anastomoses demonstrated no differences in cross-sectional areas or compliance for the three suture techniques. This suggests that, unlike with end-to-end anastomoses, when constructing an end-to-side anastomosis in patients any of the three suture techniques may be acceptable. 相似文献