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81.
Nine children with burns caused by contact with electric fire-guards are presented. A method of preventing such injuries is recommended.  相似文献   
82.
83.
The mesoaccumbens dopamine system has been hypothesized to be a common neural substrate mediating the actions of various drugs of abuse, including ethanol. However, the involvement of the mesopallidal dopamine system has received very little attention. The present study examined the effects of intraperitoneal (IP) ethanol administration on the extracellular levels of dopamine in the ventral pallidum (VP) and globus pallidus (GP) of Wistar rats. Rats were bilaterally implanted with microdialysis probes aimed at the VP and GP or nucleus accumbens (NAc) and dorsal striatum (dSTR). During microdialysis testing, rats with probes located in the VP and GP were injected IP with sterile saline or 15% (v/v) ethanol in saline at doses of 0.75, 1.5, or 2.25 g/kg. Rats with NAc and dSTR probes were injected with saline or 2.25 g/kg ethanol. The IP administration of 1.5 and 2.25 g/kg ethanol significantly (p <0.05) elevated the extracellular levels of dopamine in the VP (maximal increase: 136 and 182% of baseline, respectively) but not in the GP. No effects on extracellular dopamine levels were observed following the IP injections of 0.75 g/kg ethanol or saline. The IP administration of 2.25 g/kg ethanol significantly (p <0.05) elevated the extracellular levels of dopamine in the NAc (maximal increase: 198% of baseline) and dSTR (maximal increase: 155% of baseline). Analysis of the effects of 2.25 g/kg ethanol on dopamine release revealed greater increases in the VP, NAc, and dSTR compared to the GP. The data suggest that the mesopallidal, mesoaccumbens, and nigrostriatal dopamine systems are more sensitive to the effects of ethanol than the nigropallidal dopamine system.  相似文献   
84.
We have evaluated the spatial relationship between clotted vasculature and the structural integrity of layer V cortical neurons in YFP (yellow fluorescent protein)-H transgenic mice 2 to 10 h after photothrombotic stroke. Fortuitously, ischemic zones could be finely mapped about dysmorphic YFP labeled axons and dendrites using histology since Texas-red dextran used to assess blood flow in vivo was trapped within fixed clotted vessels. Ischemic damage to layer V neurons located at the border of ischemia was contained within apical tuft spiny dendritic structures and did not propagate to spines on the more proximal region of the apical dendrite. The lateral spread of dendritic damage decayed sharply with distance from the edge of ischemia (50% reduction in beaded dendrites within approximately 100 microm) and increased with time up to 6 h after stroke but not thereafter. Axonal damage also increased with time but extended further laterally than dendritic damage, up to 500 microm from the stroke core. Apoptotic and necrotic cell death cascades were activated 6 h after stroke; however, only within 300 microm of the ischemic core. These data suggest that the axonal and dendritic circuitry of neurons located 300 microm outside of an ischemic zone can be relatively free of damage or commitment to cell death suggesting that they may be in an ideal position to contribute to functional recovery. Given that ischemic damage may have a larger effect on circuitry involving superficial dendrites and projecting axons, it is conceivable that surviving peri-infarct neurons may have unique structural and functional properties.  相似文献   
85.
BACKGROUND: Pediatric asthma is the No. 1 chronic disease in childhood and is responsible for significant morbidity and mortality. In Nebraska, the number of asthma-related deaths is greater than the national average, and in 1998, 2 students died of acute asthma attacks while attending school in the Omaha public schools (OPSs). In response, we designed and implemented a program to respond to this problem. OBJECTIVE: To implement and study a school-based program for the treatment of life-threatening asthma and anaphylaxis in the OPSs. METHODS: The Emergency Response to Life-Threatening Asthma or Systemic Allergic Reactions (Anaphylaxis) Protocol was designed and evaluated in 78 OPSs from 1998 to 2003. Nurses and school staff were trained in the protocol, which required the use of nebulized albuterol and/or intramuscular epinephrine in conjunction with an emergency response procedure. Outcomes were measured by improvement in acute care in schools and survival of students. Results: In the 5 years of evaluation, 98 students were treated successfully. One student died. Of those treated with the protocol, equal numbers had at school both asthma action plans (AAPs) and metered-dose inhalers (MDIs), MDIs only, or neither AAPs nor MDIs. As a result of the program, there has been an increased awareness from parents, teachers, and physicians about the necessity of an emergency response program. In 2002, an outcome of the OPS program resulted in the formation of Attack on Asthma Nebraska to ensure that Nebraska schools have the education, training, and medications to respond to anyone experiencing a life-threatening asthma or anaphylaxis attack at school. The following year, a revised protocol was approved by the Nebraska State Board of Education for use in all Nebraska schools. CONCLUSIONS: Emergency response protocols provide protection for children while in school. This program should serve as a national model for other school-based programs for children and adolescents with asthma and anaphylaxis.  相似文献   
86.
BACKGROUND: There is no consensus regarding the use of specific in vitro tests for the assessment of the quality of platelet components. A literature review found that the platelet discoid shape as measured photometrically by the extent of shape change (ESC) and hypotonic shock response (HSR) correlated well with in vivo viability. The purpose of this study was to determine whether multiple research laboratories can perform the ESC and HSR assays in an accurate, reproducible manner, with acceptable sensitivity and comparable results. STUDY DESIGN AND METHODS: Eleven laboratories conducted five identical experiments, each with a different unit of platelet-rich plasma (PRP). For each experiment, 2 half-units of PRP were prepared and stored overnight: 1 half-unit at 20 to 24 degrees C in CPD (CPD-PRP) and the other at 1 to 6 degrees C with 2 mg per mL of EDTA (cold EDTA-PRP) added to produce spherical platelets with reduced HSR. Platelet suspensions having different proportions of the two PRPs were prepared and evaluated in duplicate by ESC and HSR assays, and morphologically scored by microscopy. One-way ANOVA and Duncan multiple-range tests were performed to determine significant differences in assay results for suspensions having different proportions of CPD-PRP. RESULTS: Comparable ESC (mean range: 20–28% for CPD-PRP and 1–6% for cold EDTA- PRP) and HSR (mean range: 58–81% for CPD-PRP and 12–31% for cold EDTA- PRP) measurements were obtained by nine laboratories. Duplicate testing showed high reproducibility of ESR and HSR results /in all laboratories. A 25-percent difference in the proportion of CPD-PRP (indicative of a difference of approximately 25% in the proportions of discoid and spherical platelets) was detected with a sample size of five (p<0.05) for both the ESC and HSR assays. A high correlation was found for the ESC assay and morphology score (r = 0.93, n = 345). CONCLUSION: Multiple laboratories were able to obtain comparable results with the ESC and HSR tests. They were able to show that the tests can be performed in an accurate, reproducible manner and with acceptable sensitivity.  相似文献   
87.
We describe a case of a 78-year-old man who presented with a mycotic aneurysm of the thoracic aorta caused by Clostridium septicum and underwent successful resection. There are only 3 cases of mycotic aneurysms caused by Clostridium septicum reported in the literature. Clostridium septicum infections have been shown to have a high association with gastrointestinal and hematologic malignancies. All patients with Clostridium septicum infections, therefore, require a search for gastrointestinal lesions, as they may represent a source of persistent bacteremia. This patient had no malignant lesions but did have multiple benign sigmoid polyps.  相似文献   
88.
Peripheral measures of serotonergic and noradrenergic function were obtained in 29 obsessive-compulsive adolescents and 31 age- and sex-matched controls, as well as in a subsample of 22 patients after five weeks of treatment with clomipramine hydrochloride (134 +/- 33 mg/d) (mean +/- SD) given in a double-blind placebo-controlled trial. Drug-free obsessive-compulsive subjects did not differ from controls on measures of platelet serotonin and monoamine oxidase (MAO) activity, nor on plasma epinephrine or norepinephrine concentrations at rest and after a standard orthostatic challenge procedure. Compared with placebo, treatment with clomipramine was clinically effective and produced a marked decrease in platelet serotonin concentration, a trend toward a reduction in platelet MAO activity, and a rise in standing plasma norepinephrine. Clinical improvement during drug therapy was closely correlated with pretreatment platelet serotonin concentration and MAO activity, as well as with the decrease in both measures during clomipramine administration. This suggests that the effects of clomipramine on serotonin uptake may be essential to the antiobsessional action observed.  相似文献   
89.
Inhalation anesthetics are effective chemical preconditioning agents in experimental cerebral ischemia. However, previous work has been performed exclusively in male animals. We determined if there is a gender difference in ischemic outcome after isoflurane preconditioning (IsoPC), and if this sex-specific response is linked to differences in Akt phosphorylation or expression of neuronal inducible cell-death putative kinase (NIPK), a negative modulator of Akt activation. Young and middle-aged male and female mice were preconditioned for 4 h with air (sham PC) or 1.0% IsoPC and recovered for 24 h. Cortices were subdissected from preconditioned young male and female mice for measurement of Akt phosphorylation (Western blot) and NIPK mRNA (quantitative polymerase chain reaction). Additional cohorts underwent 2 h of reversible middle cerebral artery occlusion. Lastly, male and female Akt1(+/+) and Akt1(-/-) mice were studied to determine if gender differences in ischemic outcome after IsoPC is Akt1-dependent. Infarction volume was determined at 22 h reperfusion (2,3,5-triphenyltetrazolium chloride). As expected, IsoPC decreased ischemic damage as compared with sham PC in young and middle-aged male mice. In contrast, IsoPC markedly increased infarction in young female mice and had no effect in middle-aged female mice. Cortical phospho-Akt was increased by IsoPC versus sham PC only in male mice. No increase was observed in IsoPC female mice. NIPK mRNA was higher in female mice than in male mice regardless of preconditioning status. Male IsoPC neuroprotection was lost in Akt1-deficient male mice. We conclude that IsoPC is beneficial only in ischemic male brain and that sex differences in IsoPC are mediated through Akt activation and basal NIPK expression.  相似文献   
90.
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