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111.
Terrell AM Crisostomo PR Markel TA Wang M Abarbanell AM Herrmann JL Meldrum DR 《The Journal of surgical research》2008,146(2):218-224
BACKGROUND: Females demonstrate improved cardiac recovery after ischemia/reperfusion injury compared with males. Attenuation of myocardial dysfunction with preischemic estradiol suggests that estrogen may be an important mediator of this cardioprotection. However, it remains unclear whether post-injury estradiol may have clinical potential in the treatment of acute myocardial infarction. We hypothesize that postischemic administration of 17beta-estradiol will decrease myocardial ischemia/reperfusion injury and improve left ventricular cardiac function. MATERIALS AND METHODS: Adult male Sprague Dawley rat hearts (n = 20) (Harlan, Indianapolis, IN) were isolated, perfused with Krebs-Henseleit solution via Langendorff model, and subjected to 15 min of equilibration, 25 min of warm ischemia, and 40 min reperfusion. Experimental hearts received postischemic 17beta-estradiol infusion, 1 nm (n = 4), 10 nm (n = 4), 25 nm (n = 4), or 50 nm (n = 4), throughout reperfusion. Control hearts (n = 4) were infused with perfusate vehicle. RESULTS: Postischemic recovery of left ventricular developed pressure was significantly greater with 1 nm (51.6% +/- 7.4%) and 10 nm estradiol (47.7% +/- 8.6%) than with vehicle (37.8% +/- 9.7%) at end reperfusion. There was also greater recovery of the end diastolic pressure with 1 nm (47.8 +/- 4.0 mmHg) and 10 nm estradiol (54.0 +/- 4.0) compared with vehicle (75.3 +/- 7.5). Further, 1 nm and 10 nm estrogen preserved coronary flow after ischemia and decreased coronary effluent lactated dehydrogenase compared with controls. Estrogen at 25 nm and 50 nm did not provide additional benefit in terms of functional recovery. Estrogen at all concentrations increased extracellular signal-regulated protein kinase phosphorylation. CONCLUSIONS: Postischemic infusion of 17beta-estradiol protects myocardial function and viability. The attractive potential for the clinical application of postischemic estrogen therapy warrants further study to elucidate the mechanistic pathways and differences between males and females. 相似文献
112.
The introduction of standardization in image formatting allowed the development of a picture archiving and communication
system, or filmless radiology. In practice, we have found advantages in quick access and availability, image manipulation,
and cost savings to outweigh the disadvantages of portability and system down time. 相似文献
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David L Witsell Michael G Stewart Edwin M Monsell James A Hadley Jeffrey E Terrell Maureen T Hannley Susan Sedory Holzer 《Otolaryngology--head and neck surgery》2005,132(2):171-179
OBJECTIVE: To assess outcomes for patients with chronic rhinosinusitis. STUDY DESIGN AND SETTING: Prospective, multicenter study; 31 otolaryngologists enrolled 276 adult patients with chronic rhinosinusitis; patients completed surveys at 3-month intervals, and physicians provided clinical and treatment data. The primary outcome measure was the Chronic Sinusitis Survey-Duration (CSS-D). RESULTS: One hundred seventeen adult patients completed 12-month follow-up. Most patients reported sinus symptoms lasting longer than 3 years (74%). Patients showed significant improvement (group P < 0.0001) in the CSS-D score at each follow-up interval. Baseline CSS-D ( P < 0.0001), surgical intervention ( P < 0.003), and Lund-McKay score ( P < 0.04) were predictive of clinical success in regression analysis. CONCLUSIONS: Patients referred to an otolaryngologist have a severe sinus illness. Treatment by an otolaryngologist was associated with significant improvement in sinus-related symptoms. SIGNIFICANCE: The study demonstrated the feasibility of multicenter outcome studies in chronic rhinosinusitis and generated testable hypotheses for future investigation. EBM rating: C. 相似文献
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Johnson KK Duvall D Gilcher RO Smith JW Forsberg JE Terrell DR Vesely SK George JN 《The Journal of the Oklahoma State Medical Association》2007,100(7):273-278
The Oklahoma Thrombotic ThrombocytopenicPurpura-Hemolytic Uremic Syndrome (TTP-HUS) Registry has enrolled all 335 consecutive patients from central, western and southeastern Oklahoma who had their first episode of clinically diagnosed TTP or HUS from 1989 through 2005; follow-up is complete for 333 patients. Identifying all patients is possible since plasma exchange is the essential treatment for all adults and some children with these disorders and since the Oklahoma Blood Institute (OBI) is the sole provider of plasma exchange services for this region. Patients in the Oklahoma TTP-HUS Registry have come from 46 counties and have been treated in 16 hospitals; 227 physicians have provided the principal care for these patients. A support group formed in 1996 has met 3 times each year, averaging 17 former patients plus 16 additional family members and friends. Registry data are an important source of information for physicians and their patients, providing a complete community perspective of these uncommon disorders. 相似文献
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In contrast to the murine system, long-term hamster bone marrow suspension cultures maintain proliferation of both pluripotent and committed stem cells in the absence of an adherent layer and without addition of exogenous factors, such as hydrocortisone. Addition of pokeweed-mitogen-stimulated hamster spleen conditioned medium (SCM) to these long-term suspension cultures produces an increase in the number of mixed colonies assayed in soft-agar, These mixed colonies, which contained four cell lineages--granulocytic, erythroid, megakaryocytic, and macrophage--could be generated from cells grown in suspension for over 6 mo. Addition of SCM also induces an initial rapid expansion of the myeloid compartment, and this expansion results in 70% of the cells being terminally differentiated granulocytes. In contrast, addition of SCM to hamster bone marrow cultures containing both adherent cells and hematopoietic stem cells produced no change in the number of mixed colonies generated in the culture. This system allows the in vitro study of the process of stem cell proliferation and differentiation and also provides a means to examine the relationship of adherent and supernatant bone marrow populations. 相似文献