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21.
Improving survival rates for out of hospital cardiac arrest (OHCA) at the neighborhood level is increasingly seen as priority in US cities. Since wide disparities exist in OHCA rates at the neighborhood level, it is necessary to locate neighborhoods where people are at elevated risk for cardiac arrest and target these for educational outreach and other mitigation strategies. This paper describes a GIS-based methodology that was used to identify communities with high risk for cardiac arrests in Franklin County, Ohio during the period 2004–2009. Prior work in this area used a single criterion, i.e., the density of OHCA events, to define the high-risk areas, and a single analytical technique, i.e., kernel density analysis, to identify the high-risk communities. In this paper, two criteria are used to identify the high-risk communities, the rate of OHCA incidents and the level of bystander CPR participation. We also used Local Moran’s I combined with traditional map overlay techniques to add robustness to the methodology for identifying high-risk communities for OHCA. Based on the criteria established for this study, we successfully identified several communities that were at higher risk for OHCA than neighboring communities. These communities had incidence rates of OHCA that were significantly higher than neighboring communities and bystander rates that were significantly lower than neighboring communities. Other risk factors for OHCA were also high in the selected communities. The methodology employed in this study provides for a measurement conceptualization of OHCA clusters that is much broader than what has been previously offered. It is also statistically reliable and can be easily executed using a GIS.  相似文献   
22.
Nakamura  H; Said  JW; Miller  CW; Koeffler  HP 《Blood》1993,82(3):920-926
p53 mutations are found in a variety of neoplasia. B-immunoblastic lymphoma (BIBL) is a rapidly progressive, aggressive lymphoma. As patients with acquired immunodeficiency syndrome (AIDS) live longer, BIBL is becoming an increasing problem. We asked three questions in our study. What is the frequency of p53 mutations in BIBL? Is it more frequent in patients with AIDS? Can immunohistochemical staining of lymph nodes for expression of p53 substitute for mutational analysis of p53 to detect lymphomas with mutated p53? Exons 5, 6, 7, 8 of the p53 gene (hot-spots for mutations) were amplified and examined for mutations by single-strand conformation polymorphism (SSCP) analysis. Altered migration was observed in 7 of 52 BIBL samples. Of these, 4 of 25 were from individuals infected with human immunodeficiency virus (HIV) and 3 of 27 were not infected with HIV. Direct sequencing of amplified material confirmed the presence of mutations in exons 5, 7, 8 of p53. A total of 26 BIBL as well as other lymphoma/leukemia samples, stained strongly by immunohistochemistry with three antibodies directed against human p53. Five of 6 BIBL samples with p53 mutations stained strongly for p53, but 20 lymphoma samples with no detectable p53 mutations also stained strongly for p53. Of note, however, 10 hyperplastic, nonmalignant lymph nodes from individuals either infected or not infected with HIV had negligible staining for p53 protein. In conclusion, p53 mutations occur in about 14% BIBL samples; the frequency of p53 mutations in BIBL in individuals with and without AIDS was similar. Positive p53 immunohistochemistry did not correlate with detectable p53 mutations in the same tissue, but positive immunohistochemical staining for p53 was only found in neoplastic lymph nodes. This latter finding provides a strong warning that p53 immunochemistry with available reagents cannot be used to determine which tumors have mutations of p53.  相似文献   
23.
Gurney  JW; Bates  FT 《Radiology》1989,173(1):27-31
A rare pulmonary manifestation of the acquired immunodeficiency syndrome or intravenous (IV) drug abuse is upper lobe cystic disease--pneumatoceles in Pneumocystis carinii pneumonia (PCP) and bullous emphysema in IV drug abuse. Because these disorders overlap, the radiographic findings in 56 patients were compared. During a 12-month period, 16 patients less than 40 years of age were found to have bullous emphysema; the 10 who were IV drug abusers constituted group 1. In the same time period, 40 patients with PCP were encountered; the eight (20%) who had or developed pneumatoceles constituted group 2. In both groups, the conventional radiographic manifestations of upper lobe cystic disease were similar. Eight patients underwent computed tomography of the chest. In five patients with bullous disease, the distribution of the bullous lesions was peripheral, with sparing of the central portions of the lungs. In contrast, PCP pneumatoceles in three patients were dispersed throughout the lung parenchyma.  相似文献   
24.

Purpose

In hospital-based studies, patients intubated by physicians while in an inclined position compared to supine position had a higher rate of first pass success and lower rate of peri-intubation complications. We evaluated the impact of patient positioning on prehospital endotracheal intubation in an EMS system with rapid sequence induction capability. We hypothesized that patients in the inclined position would have a higher first-pass success rate.

Methods

Prehospital endotracheal intubation cases performed by paramedics between 2012 and 2017 were prospectively collected in airway registries maintained by a metropolitan EMS system. We included all adult (age?≥?18?years) non-traumatic, non-arrest patients who received any attempt at intubation. Patients were categorized according to initial positioning: supine or inclined. The primary outcome measure was first pass success with secondary outcomes of laryngoscopic view and challenges to intubation.

Results

Of the 13,353 patients with endotracheal intubation attempted by paramedics during the study period, 4879 were included for analysis. Of these, 1924 (39.4%) were intubated in the inclined position. First pass success was 86.3% among the inclined group versus 82.5% for the supine group (difference 3.8%, 95% CI: 1.5%–6.1%). First attempt laryngeal grade I view was 62.9% in the inclined group versus 57.1% for the supine group (difference 5.8%, 2.0–9.6). Challenges to intubation were more frequent in the supine group (42.3% versus 38.8%, difference 3.5%, 0.6–6.3).

Conclusion

Inclined positioning was associated with a better grade view and higher rate of first pass success. The technique should be considered as a viable approach for prehospital airway management.  相似文献   
25.
Objective: In recent years, the costs of epinephrine autoinjectors (EAIs) in the United States have risen substantially. King County Emergency Medical Services implemented the “Check and Inject” program to replace EAIs by teaching emergency medical technicians (EMTs) to manually aspirate epinephrine from a single-use 1 mg/mL epinephrine vial using a needle and syringe followed by prehospital intramuscular administration of the correct adult or pediatric dose of epinephrine for anaphylaxis or serious allergic reaction. Treatment was guided by an EMT protocol that required a trigger and symptoms. We sought to determine if the “Check and Inject” program was safely implemented by EMTs treating presumed prehospital anaphylaxis or serious allergic reaction. Methods: We conducted a prospective investigation of all cases treated as part of the “Check and Inject” program from July 2014 through December 2016 in suburban King County, Washington, and January 2016 through December 2016 within the city of Seattle. All cases were prospectively collected using a custom quality improvement data form completed by the first responding EMTs. Two physicians completed a structured review of each EMS medical record to determine if the EMTs followed the Check and Inject protocol and determine if epinephrine was clinically-indicated based on physician review. Results: Of the 411 cases eligible for analysis, EMTs followed the protocol appropriately in 367 (89.3%) cases. In the remaining 44 (10.7%) cases, the EMS incident report form failed to document either a clear inciting allergic trigger or an appropriate symptom from the protocol list. Physician review determined that epinephrine was clinically indicated in 36 of the 44 cases. Among the remaining 8 cases (1.9%) that did not meet protocol criteria and were not clinically-indicated based on physician review, none had a documented adverse reaction to the epinephrine. Conclusion: We observed that EMTs successfully implemented the manual “Check and Inject” program for severe allergic reactions and anaphylaxis in a manner that typically agreed with physician review and without any overt identified safety issues.  相似文献   
26.
Radiomethyl incorporation in vitro into Nepsilon-methyllysine of histones from rat liver nuclei incubated in the presence of S-adenosyl[methyl-3H]methionine is stimulated if the polycations polylysines, protamines, or histones are added to the incubation mixture. Maximal stimulation occurs at a cation/nucleotide ratio of 0.5. Past this point stimulation drops, except in the case of very lysine-rich histone H-1, for which the maximal level of incorporation remains constant upon further addition of this histone. Bio-Gel P-10 chromatography, differential precipitation, and gel electrophoresis of radiomethylated histones indicate that although the usual incorporation of radiomethyl into histone H-3 is not affected, active methylation of H-1 occurs in the presence of polycations. Column chromatographic amino acid analysis reveals that the methylation of H-1 will specifically generate Nepsilon-monomethyllysine. Except for this condition, H-1 is never methylated in vivo or in incubated cell nuclei. Because H-1 is the weakest bound histone in chromatin, the above phenomena may be explained by assuming that, within the chromatin, polycations displace the lysine-rich histone towards the nucleosome, which results in its abberant methylation, assuming that the native nucleosome is the seat of the histone lysine methyltransferase.  相似文献   
27.
乐胃煎逆转胃癌前病变AgNOR及细胞图像分析   总被引:3,自引:0,他引:3  
目的研究乐胃煎逆转胃癌前病变不完全结肠型肠化和/或中度异型增生的疗效.方法胃镜病理证实为不完全结肠型肠化和/或中度异型增生46例.治疗组30例用乐胃煎,对照组16例用德诺(De_Nol).治疗前后胃镜活检胃窦固定部位粘膜标本作AgNOR染色及细胞图像分析.结果乐胃煎对不完全结肠型肠化及中度异型增生总有效率均高于De_Nol,分别为72%比25%(P<005)和895%比444%(P<005).乐胃煎治疗前后,AgNOR计数分别为730±116和481±150(P<001),De_Nol组为773±092和705±102(P<001).两组治疗前后AgNOR计数差值均数相比,统计学上也有显著性差异,分别为252±154和069±048(P<001).乐胃煎组中20例作细胞图像分析,治疗后各参数(长轴、短轴、核浆比、结构异型指数等)均有不同程度的降低,有显著性差异.结论乐胃煎确有较好地逆转胃癌前病变的功效.  相似文献   
28.
29.
Ruptured vertebrobasilar dissecting aneurysms require urgent, often challenging treatment as they have with a high re-hemorrhage rate within the first 24 hours. The patient is a 57-year-old woman who presented with severe-sudden onset headache. Further work up showed a ruptured dissecting aneurysm of the caudal loop of the posterior inferior cerebellar artery (PICA) with associated narrowing distally, in the ascending limb. The aneurysm was immediately occluded with a Woven Endobridge (WEB) device (MicroVention, Tustin, CA, USA) while flow diversion treatment of the diseased ascending limb was postponed. Follow-up angiography three months later showed complete occlusion of the aneurysm, as well as healing of the diseased distal vessel, obviating the need for further intervention. WEB embolization of a ruptured dissecting posterior circulation aneurysm provided an excellent outcome for this patient.  相似文献   
30.
The present studies report erythropoietin (Ep) production in primary cultures of a human renal carcinoma from a patient with erythrocytosis that has been serially transplanted to BALB/c nude mice. The levels of erythropoietin in the culture media were estimated using the exhypoxic polycythemic mouse assay (EHPCMA), fetal mouse liver erythroid colony- forming technique (FMLC), and a radioimmunoassay (RIA). The spent culture media of the exponentially growing cells contained less than 10 mU/ml of Ep measured by RIA. However, after the cells became confluent, Ep levels (RIA) in the spent media showed a marked increase to approximately 300 mU/ml. Ep levels estimated using the FMLC and EHPCMA were approximately 2/3 and 1/10, respectively, of those measured by RIA. Rabbit antiserum to highly purified human urinary Ep (70,400 U/mg protein) was utilized for immunocytochemical (peroxidase-antiperoxidase method) localization of Ep in the cultured cells. Very few of the cells in exponential growth exhibited Ep-like immunoreactivity, whereas intense Ep-like immunoreactivity was observed in the cytoplasm of the cells maintained in culture for a prolonged period after reaching confluency. The most intense staining was observed in some of the cells forming domes. The domes developed after the cells reached confluency, and their numbers increased with increasing time in confluent culture, in parallel with the increase in Ep levels in the spent media. This primary cell culture system of a renal cell carcinoma maintained in nude mice, which produces immunologically and biologically active Ep, may provide a useful model for studies of the mechanism of Ep production.  相似文献   
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