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491.

Background and Purpose

Timely intravenous (IV) thrombolysis for acute ischemic stroke is associated with better clinical outcomes. Acute stroke care implemented with “Stroke Code” (SC) may increase IV tissue plasminogen activator (tPA) administration. The present study aimed to investigate the impact of SC on thrombolysis.

Methods

The study period was divided into the “pre-SC era” (January 2006 to July 2010) and “SC era” (August 2010 to July 2013). Demographics, critical times (stroke symptom onset, presentation to the emergency department, neuroimaging, thrombolysis), stroke severity, and clinical outcomes were recorded and compared between the two eras.

Results

During the study period, 5957 patients with acute ischemic stroke were admitted; of these, 1301 (21.8%) arrived at the emergency department within 3 h of stroke onset and 307 (5.2%) received IV-tPA. The number and frequency of IV-tPA treatments for patients with an onset-to-door time of <3 h increased from the pre-SC era (n = 91, 13.9%) to the SC era (n = 216, 33.3%) (P<0.001). SC also improved the efficiency of IV-tPA administration; the median door-to-needle time decreased (88 to 51 min, P<0.001) and the percentage of door-to-needle times ≤60 min increased (14.3% to 71.3%, P<0.001). The SC era group tended to have more patients with good outcome (modified Rankin Scale ≤2) at discharge (49.5 vs. 39.6%, P = 0.11), with no difference in symptomatic hemorrhage events or in-hospital mortality.

Conclusion

The SC protocol increases the percentage of acute ischemic stroke patients receiving IV-tPA and decreases door-to-needle time.  相似文献   
492.
Duggal  Arti  Dumas  M.T.  Jeng  R.S.  Hubbes  M. 《Mycopathologia》1997,140(1):35-49
Eighteen isolates representing six Fusarium species from diverse hosts and geographical origins were evaluated to determine ribosomal DNA variation using polymerase chain reaction and restriction fragment length polymorphisms. No length variation was observed for amplified 18S and 28S regions. However, amplification of the ITS region showed one isolate, a F. oxysporum, to be about 120 bp larger than the remaining 17. Restriction digestions in the 18S region revealed polymorphisms within species of F. oxysporum and F. solani. An amplified variable stretch of the 28S gene showed restriction site differences between F. avenecum, F. sambucinum and F. sporotrichioides. A large degree of polymorphism was observed both between and within species in the ITS region. Therefore, entire sequences of the ITS and the 5.8S subunit were obtained for 17 of the 18 isolates. These sequences, along with those from eight additional isolates, were analysed using PAUP to assess the occurrence of DNA sequence divergence within the ITS region. The lack of correlation between molecular-based relationships and species affinities inferred from morphology for some isolates indicates that species designation can be unreliable using morphological data alone. Possible reasons for the discordance of the sequence and morphological data are discussed. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
493.
ABSTRACT: BACKGROUND: Daidzein, a phytoestrogen found in isoflavone, is known to exert neurotrophic and neuroprotective effects on the nervous system. Using primary rat dorsal root ganglion (DRG) neuronal cultures, we have examined the potential neurite outgrowth effect of daidzein. METHODS: Dissociated dorsal root ganglia (DRG) cultures were used to study the signaling mechanism of daidzein-induced neuritogenesis by immunocytochemistry and Western blotting. RESULTS: In response to daidzein treatment, DRG neurons showed a significant increase in total neurite length and in tip number per neuron. The neuritogenic effect of daidzein was significantly hampered by specific blockers for Src, protein kinase C delta (PKCdelta) and mitogen-activated protein kinase/extracellular signal-regulated kinase kinases (MEK/ERK), but not by those for estrogen receptor (ER). Moreover, daidzein induced phosphorylation of Src, PKCdelta and ERK. The activation of PKCdelta by daidzein was attenuated in the presence of a Src kinase inhibitor, and that of ERK by daidzein was diminished in the presence of either a Src or PKCdelta inhibitor. CONCLUSION: Daidzein may stimulate neurite outgrowth of DRG neurons depending on Src kinase, PKCdelta and ERK signaling pathway.  相似文献   
494.
To understand the interactions between substance P and gut inflammation, changes in substance P levels were evaluated in a chronic model of ileitis in response to three anti-inflammatory agents with distinct mechanisms of action. The agents were the prostaglandin E(1) analogue misoprostol (30 mug/kg, s.c., b.i.d.), the nitric oxide synthase inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME, 100 mug/ml in drinking water) and the leumedin, N-(fluorenyl-9-methoxycarbonyl)-L-leucine (NPC 15199, 10 mg/kg, s.c.). Ileitis was induced by a transmural injection of trinitrobenzene sulphonic acid (TNBS 30 mg/kg in 50% ethanol) into the distal ileum of guinea-pigs. All anti-inflammatory therapies were introduced after TNBS administration and continued until day 7, when guinea-pigs were killed. Ileal substance P levels were measured by radioimmunoassay, and granulocyte infiltration was quantified by myeloperoxidase (MPO) activity. Protein and nitrite (an index of nitric oxide formation) levels in a luminal saline lavage were quantified in all groups. TNBS ileitis caused a marked reduction in ileal substance P content and increased MPO activity, protein and nitrite secretion. The nitric oxide synthase inhibitor, L-NAME, completely restored all parameters to baseline. Misoprostol attenuated the granulocyte infiltration and exacerbated protein leak but had no effect on substance P levels. In contrast, NPC 15199 had no effect on granulocyte infiltration but normalized substance P levels and protein leak. Only L-NAME and NPC 15199 blocked the TNBS induced increase in nitrite levels. These results suggest that the regulation of granulocyte infiltration in this model is unrelated to changes in substance P levels. Inhibition of nitric oxide synthase was the most effective therapeutic strategy in TNBS ileitis but the precise interactions between nitric oxide and the enteric nervous system during inflammatory states remain to be defined.  相似文献   
495.
496.
With an automated computerized temperature control and a specialized temperature measurement system, dry spores of Bacillus subtilis subsp. niger were treated with heat simultaneously in a convection dry-heat oven and a microwave oven. The temperature of the microwave oven was monitored such that the temperature profiles of the spore samples in both heat sources were nearly identical. Under these experimental conditions, we unequivocally demonstrated that the mechanism of sporicidal action of the microwaves was caused solely by thermal effects. Nonthermal effects were not significant in a dry microwave sterilization process. Both heating systems showed that a dwelling time of more than 45 min was required to sterilize 10(5) inoculated spores in dry glass vials at 137 degrees C. The D values of both heating systems were 88, 14, and 7 min at 117, 130, and 137 degrees C, respectively. The Z value was estimated to be 18 degrees C.  相似文献   
497.
Pronase digestion was used to study the surface disposition of apoproteins on high density lipoproteins. After digestion the average density of high density lipoproteins decreased from 1.14 to 1.10 g/ml. The immunoreactivities of apoproteins A-II, C-II, and C-III were completely destroyed, but 80% of the reactivity of ApoA-I was retained. Only 5–10% of ApoA-I reacts with anti ApoAI antisera in intact high density lipoproteins. The similar accessibility of ApoA-I to pronase and to antibodies suggests that pronase hydrolyzes only the exposed regions of protein moieties. Pronase may be an ideal probe for distinguishing the exposed regions of apoproteins in lipoproteins from those that are buried.  相似文献   
498.
Ingming Jeng 《Life sciences》1984,35(21):2143-2148
Butyrate induced marked morphological changes in cultured human retinal pigment epithelial (RPE) cells. The cells assumed a flattened structure within six hours of exposure to butyrate. The butyrate-treated retinal pigment epithelial cells possessed an enhanced capacity to esterify retinol. Among all short chain organic acids tested, butyrate was by far the most effective, followed by pentanoate and hexanoate. The inductive effect of butyrate was specific for retinol esterification, since the incorporations of fatty acid into phosphatidyl choline and cholesteryl ester were not enhanced. Time-dependent, butyrate-enhanced retinol esterification may be related to the inhibition of cell proliferation. This represents the first report on the induction of retinol esterification in cultured retinal pigment epithelial cells.  相似文献   
499.
500.
A rapid method for isolating the α and γ subunits of mouse submaxillary gland nerve growth factor, as by-products of the commonly used Bocchini-Angeletti (2.5 S) procedure, has been devised. Approximately 40 mg of each subunit is obtained from 400 pairs of adult glands. The subunits isolated in this fashion are indistinguishable from those obtained from the homogeneous 7 S complex as judged by gel electrophoresis or their association-dissociation behavior.  相似文献   
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