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Measures of CO2 have been shown to correlate with coronary perfusion pressure and cardiac output during cardiac arrest. We evaluated arterial pH (pHa) relative to blood flow during cardiac arrest in a canine electromechanical dissociation (EMD) model of cardiac arrest using different resuscitation techniques. Following 15 min of cardiac arrest, 24 mongrel dogs received epinephrine with continued CPR or closed-chest cardiopulmonary bypass. Central arterial blood gases, end-tidal carbon dioxide (PetCO2), coronary perfusion pressure and cardiac output were measured. During CPR, prior to epinephrine or bypass, there was no correlation of pHa, PACO2 and PetCO2, with cardiac output or coronary perfusion pressure. Immediately after instituting the resuscitation techniques, both pHa and PaCO2 showed a significant correlation with cardiac output (pHa; R = -0.78, P less than 0.001 and PaCO2; R = 0.87, P less than 0.001) and with coronary perfusion pressure (pHa; R = -0.75, P less than 0.001 and PaCO2; R = 0.75, P less than 0.001). Eventual survivors (n = 15) had an early significant decrease in pHa, base excess and a significant increase in PaCO2 which was not present in non-survivors (n = 9). Neither pHa nor PaCO2 correlate with blood flow under low flow conditions of CPR. However, with effective circulatory assistance, pHa and PaCO2 reflect systemic blood flow and reperfusion washout. 相似文献
13.
George N Papanikolaou Maria S Baltogianni Despina G Contopoulos-Ioannidis Anna-Bettina Haidich Ioannis A Giannakakis John PA Ioannidis 《BMC medical research methodology》2001,1(1):3
Background
Guidelines published in major medical journals are very influential in determining clinical practice. It would be essential to evaluate whether conflicts of interests are disclosed in these publications. We evaluated the reporting of conflicts of interest and the factors that may affect such disclosure in a sample of 191 guidelines on therapeutic and/or preventive measures published in 6 major clinical journals (Annals of Internal Medicine, BMJ, JAMA, Lancet, New England Journal of Medicine, Pediatrics) in 1979, 1984, 1989, 1994 and 1999.Results
Only 7 guidelines (3.7%) mentioned conflicts of interest and all were published in 1999 (17.5% (7/40) of guidelines published in 1999 alone). Reporting of conflicts of interest differed significantly by journal (p=0.026), availability of disclosure policy by the journal (p=0.043), source of funding (p < 0.001) and number of authors (p=0.004). In the entire database of 191 guidelines, a mere 18 authors disclosed a total of 24 potential conflicts of interest and most pertained to minor issues.Conclusions
Despite some recent improvement, reporting of conflicts of interest in clinical guidelines published in influential journals is largely neglected.14.
Nicolaos C. Tassopoulos Krzysztof Krawczynski Angelos Hatzakis Antigoni Katsoulidou Ioanna Delladetsima Maria G. Koutelou Dimitrios Trichopoulos 《Journal of medical virology》1994,42(2):124-128
The aim of this study was to determine the frequency of hepatitis E virus (HEV) infection in a population of Greek adults with community-acquired (sporadic) non-A, non-B hepatitis found to be seronegative for antibodies to hepatitis C virus (anti-HCV). All patients admitted to the Liver Unit of Western Attica General Hospital and diagnosed as having acute community-acquired non-A, non-B hepatitis between February, 1986, and May, 1990, were enrolled in follow up studies (n = 66). Nineteen patients with HCV infection and 11 patients with acute non-A, non-B, non-C hepatitis that progressed to chronicity were excluded. Convalescent sera were tested for antibody to HEV (anti-HEV) by a fluorescent antibody blocking assay in 33 of 36 eligible patients. One of the 33 (3%) patients was found to be positive for anti-HEV. Anti-HEV testing of all 20 available serum specimens from this patient showed evidence of anti-HEV seroconversion at the fourth week after the onset of hepatitis. The patient had not travelled abroad or within Greece or had not had apparent contact with people from foreign countries for the previous 3 months. These data show that HEV infection is not a major cause of community-acquired non-A, non-B hepatitis in Greece. However, the reported case of HEV hepatitis suggests that HEV may retain a low endemicity in Greece. More extensive seroprevalence studies are needed for an accurate estimation of the extent of HEV infection in the southeastern European countries. © 1994 Wiiey-Liss, Inc. 相似文献
15.
The objective of the current modeling analysis was three-fold: (1) to examine usual nutrient intakes in children when eggs are added into dietary patterns that typically do not contain eggs; (2) to examine usual nutrient intakes with the addition of eggs in the Child and Adult Care Food Program (CACFP) school breakfast; and (3) to examine nutrient adequacy when eggs are included in routine breakfast patterns and with the addition of eggs to the CACFP school breakfast program. Dietary recall data from the National Health and Nutrition Examination Survey 2011–2016 (children aged 1–18 years-old; n = 9254; CACFP n = 159) were used in the analysis. The usual intakes of pantothenic acid, riboflavin, selenium, and vitamin D increased ≥10 percent (relative to the baseline values) with the addition of one egg at breakfast. The usual intakes of protein and vitamin A at breakfast were also increased by more than 10 percent compared to the baseline values with the addition of two eggs. Similar outcomes were observed with the addition of eggs to the CACFP school breakfast. The percent of children above the adequate intake for total choline increased to 43.6 and 57.8% with one and two eggs, respectively, compared to 22.6% at the baseline. The addition of eggs at breakfast can contribute to nutrient intakes and overall dietary adequacy and play a role in public health initiatives aimed at increasing the intake of under-consumed nutrients and nutrients of concern. 相似文献
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Tanaz Vaghaiwalla Brian Ruhle Kelvin Memeh Peter Angelos Edwin Kaplan Chih-Yi Liao Blase Polite Xavier Keutgen 《Surgery》2021,169(1):162-167
BackgroundPeptide receptor radionuclide therapy is a targeted therapy used to treat unresectable somatostatin receptor-positive neuroendocrine tumors. The objective of this study was to evaluate response rates among neuroendocrine tumors of different primaries and identify factors relevant to future treatment strategies.MethodsWe retrospectively reviewed patients who received peptide receptor radionuclide therapy for neuroendocrine tumors from 2018 to 2019 at our institution. Patients were assessed with computed tomography/magnetic resonance imaging and 68Ga-DOTATATE-positron emission tomography before and after 2 or 4 cycles of peptide receptor radionuclide therapy. Tumor response was evaluated by RECIST 1.1. Statistics included multinomial logistic regression models and Fisher exact test.ResultsTwenty-seven patients underwent 92 cycles of peptide receptor radionuclide therapy: pancreas (n = 11), small bowel (n = 7), and other (n = 9) neuroendocrine tumors. Overall, 30% (8 of 27) had partial response, 59% (16 of 27) stable disease, and 11% (3 of 27) progressed. Pancreatic neuroendocrine tumors responded differently from small bowel neuroendocrine tumors regardless of cycle number (P = .01). The majority of pancreatic neuroendocrine tumors (6 of 11) had partial response to peptide receptor radionuclide therapy, while all small bowel neuroendocrine tumors had stable disease. Pancreatic neuroendocrine tumors stable after 2 cycles were more likely to respond to additional cycles versus other neuroendocrine tumors (probability: 60% vs 11%).ConclusionPatients with unresectable advanced or metastatic pancreatic neuroendocrine tumors may benefit from a full course of peptide receptor radionuclide therapy, whereas other neuroendocrine tumors appear less likely to respond. Large prospective studies are needed to confirm these findings. 相似文献
18.
OBJECTIVES: To re-examine the potential influence of varicocelectomy on testicular volume using scrotal ultrasonography, because it has been reported that total testicular volume (assessed by physical examination) increases after adult varicocele ligation. METHODS: A retrospective review of the testicular volume and semen parameters of 61 men who underwent microsurgical varicocelectomy between 1996 and 1998 was performed. Ultrasound-derived testicular volumes and total motile sperm counts were compared before varicocelectomy and at a mean of 7.2 months postoperatively. RESULTS: Bilateral varicocelectomy was performed in 22 men; 39 men underwent a left-sided procedure only. Overall, no significant change was found in the mean total testicular volume after varicocelectomy compared with preoperatively (24.0 versus 23.9 mL, respectively; P = 0.74). Similarly, the testicular volumes did not change significantly after left or bilateral varicocelectomy (P >0.05). Overall, the mean total motile sperm count increased significantly after varicocelectomy (17. 9 to 25.4, P = 0.05). CONCLUSIONS: This was the first study to examine the effect of adult varicocelectomy on testicular volume using ultrasound-derived measurements of volume. Unlike previous findings, our data suggest that although adult varicocelectomy improves semen quality in most infertile men, it does not result in a significant increase in testicular volume. 相似文献
19.
Alexandros Papanikolaou Qian-Shu Wang Don A. Delker Daniel W. Rosenberg 《Cancer letters》1998,130(1-2):29-34
Azoxymethane (AOM) is an organotropic colon carcinogen that is commonly used to induce colon tumors in rodents. Unlike its parent compound, 1,2-dimethylhydrazine (DMH), a tumor susceptibility phenotype in inbred mice with respect to AOM has not been established. Thus, this study was undertaken to determine whether genetic susceptibility extends to this carcinogen. SWR/J, A/J (both susceptible to DMH carcinogenesis) and AKR/J (resistant) mice were treated with 10 mg/kg AOM i.p. once a week for 8 weeks. Twenty-five weeks after the initial injection, tumor yield was determined. With a single exception, only SWR/J and A/J mice developed tumors, with a distribution that was limited to the distal colon (16.3±1.1 and 36.4±2.4, respectively). The formation of aberrant crypt foci (ACF), putative preneoplastic lesions, was also assessed in whole-mount colons using Methylene Blue staining. Consistent with tumor multiplicity, the total number of ACF was highest in A/J mice, followed by SWR/J mice. In addition, A/J mice had a significantly greater number of large ACF (five or more crypts per foci) than the other strains. Despite the absence of colon tumors, however, AKR/J mice did develop a significant number of ACF. This finding suggests that ACF in resistant mice are persistent but do not progress to tumors. 相似文献
20.