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131.
132.
Barzegar-Amini Maral Mahmoudi Mahmoud Dadgarmoghaddam Maliheh Farzad Faramarz Najafabadi Ali Qaraee Jabbari-Azad Farahzad 《Journal of clinical immunology》2022,42(1):10-18
Journal of Clinical Immunology - The present study aimed to compare serum total IgA levels between severe and mild COVID-19 patients’ groups and the control group. In this cross-sectional... 相似文献
133.
Multivariate scan statistics for disease surveillance 总被引:1,自引:0,他引:1
Kulldorff M Mostashari F Duczmal L Katherine Yih W Kleinman K Platt R 《Statistics in medicine》2007,26(8):1824-1833
In disease surveillance, there are often many different data sets or data groupings for which we wish to do surveillance. If each data set is analysed separately rather than combined, the statistical power to detect an outbreak that is present in all data sets may suffer due to low numbers in each. On the other hand, if the data sets are added by taking the sum of the counts, then a signal that is primarily present in one data set may be hidden due to random noise in the other data sets.In this paper, we present an extension of the spatial and space-time scan statistic that simultaneously incorporates multiple data sets into a single likelihood function, so that a signal is generated whether it occurs in only one or in multiple data sets. This is done by defining the combined log likelihood as the sum of the individual log likelihoods for those data sets for which the observed case count is more than the expected. We also present another extension, where the concept of combining likelihoods from different data sets is used to adjust for covariates.Using data from the National Bioterrorism Syndromic Surveillance Demonstration Project, we illustrate the new method using physician telephone calls, regular physician visits and urgent care visits by Harvard Pilgrim Health Care members cared for by Harvard Vanguard Medical Associates, a large multi-specialty group practice in Massachusetts. For upper and lower gastrointestinal (GI) illness, there were on average 20 telephone calls, nine urgent care visits and 22 regular physician visits per day. The strongest signal was generated by a single data set and due to a familial outbreak of pinworm disease. The second and third strongest signals were generated by the combined strength of two of the three data sets. 相似文献
134.
The benefit of coarctation repair on the resolution of systolic hypertension in adults has been questioned. In this retrospective study, hypertension was assessed in 38 adults (22 men, 16 women; mean age, 25.6 +/- 6.9 years; range, 16-39 years) who underwent coarctation repair between 1996 and 2006. Thirty patients had preoperative hypertension (mean systolic pressure, 158.3+/-18.6; range 140-200 mm Hg). At preoperative catheterization, the peak mean systolic gradient across the coarctation was 70.6 +/- 21.2 mm Hg (range, 38-120 mm Hg). Operative procedures were resection and end-to-end anastomosis (11 patients), patch aortoplasty (24) and resection with interposition of a Dacron tube graft (3). The patients were followed up for 2-90 months (mean, 37 +/- 23 months). Of the 30 patients with preoperative hypertension, 25 (83%) were normotensive at the last follow-up. The mean postoperative systolic blood pressure was significantly lower than the preoperative level. More than half of the patients (58%) were still taking antihypertensive medication. Surgical repair of coarctation of the aorta in adults can lead to regression of systolic hypertension and a decreased requirement for antihypertensive medication. 相似文献
135.
An economic evaluation of voriconazole versus amphotericin B for the treatment of invasive aspergillosis in Canada. 总被引:1,自引:0,他引:1
Coleman Rotstein Michel Laverdière Anne Marciniak Farzad Ali 《The Canadian Journal of Infectious Diseases & Medical Microbiology》2004,15(5):277-284
BACKGROUND: Invasive aspergillosis (IA) is a serious fungal infection that affects immunocompromised patients. The Global Comparative Aspergillosis study demonstrated that voriconazole, a new broad-spectrum triazole, had better responses and improved survival compared with conventional amphotericin B deoxycholate (CAB) and other licensed antifungal therapy (OLAT) for the treatment of definite or probable aspergillosis. OBJECTIVES: To compare costs and outcomes of voriconazole and CAB for the treatment of definite or probable aspergillosis in Canada. METHODS: A cost-consequence decision tree model was designed to reflect the treatment pathways used in clinical practice when using voriconazole or CAB as primary therapy for IA. Therapy included initial treatment with either voriconazole or CAB and then switched to an OLAT in the event of an inadequate response, severe toxicity or intolerance. The principal data source used was the Global Comparative Aspergillosis study. RESULTS: The total cost of voriconazole when compared with CAB as initial therapy for IA was $38,319 versus $42,495 per patient, respectively, representing a 9.8% cost reduction for each patient treated with voriconazole. The higher mean cost in the CAB arm was primarily due to the high proportion of patients (73.7%) who were switched to an OLAT due to severe side effects or an inadequate response. Treating with voriconazole was a dominant strategy. The number of patients that had to be treated with voriconazole instead of CAB to save one additional life was eight. CONCLUSIONS: Voriconazole as primary treatment for IA increased the chances of successful treatment, improved survival and may represent a potential cost saving strategy in Canada. 相似文献
136.
Dhamoon AS Pandit SV Sarmast F Parisian KR Guha P Li Y Bagwe S Taffet SM Anumonwo JM 《Circulation research》2004,94(10):1332-1339
The inwardly rectifying potassium (Kir) 2.x channels mediate the cardiac inward rectifier potassium current (I(K1)). In addition to differences in current density, atrial and ventricular I(K1) have differences in outward current profiles and in extracellular potassium ([K+]o) dependence. The whole-cell patch-clamp technique was used to study these properties in heterologously expressed Kir2.x channels and atrial and ventricular I(K1) in guinea pig and sheep hearts. Kir2.x channels showed distinct rectification profiles: Kir2.1 and Kir2.2 rectified completely at potentials more depolarized than -30 mV (I approximately 0 pA). In contrast, rectification was incomplete for Kir2.3 channels. In guinea pig atria, which expressed mainly Kir2.1, I(K1) rectified completely. In sheep atria, which predominantly expressed Kir2.3 channels, I(K1) did not rectify completely. Single-channel analysis of sheep Kir2.3 channels showed a mean unitary conductance of 13.1+/-0.1 pS in 15 cells, which corresponded with I(K1) in sheep atria (9.9+/-0.1 pS in 32 cells). Outward Kir2.1 currents were increased in 10 mmol/L [K+]o, whereas Kir2.3 currents did not increase. Correspondingly, guinea pig (but not sheep) atrial I(K1) showed an increase in outward currents in 10 mmol/L [K+]o. Although the ventricles of both species expressed Kir2.1 and Kir2.3, outward I(K1) currents rectified completely and increased in high [K+]o-displaying Kir2.1-like properties. Likewise, outward current properties of heterologously expressed Kir2.1-Kir2.3 complexes in normal and 10 mmol/L [K+]o were similar to Kir2.1 but not Kir2.3. Thus, unique properties of individual Kir2.x isoforms, as well as heteromeric Kir2.x complexes, determine regional and species differences of I(K1) in the heart. 相似文献
137.
Sarmast F Kolli A Zaitsev A Parisian K Dhamoon AS Guha PK Warren M Anumonwo JM Taffet SM Berenfeld O Jalife J 《Cardiovascular research》2003,59(4):863-873
OBJECTIVE: We tested the hypothesis that left atrial (LA) myocytes are more sensitive to acetylcholine (ACh) than right atrial (RA) myocytes, which results in a greater dose-dependent increase in LA than RA rotor frequency, increased LA-to-RA frequency gradient and increased incidence of wavelet formation during atrial fibrillation (AF). METHODS AND RESULTS: AF was induced in seven Langendorff-perfused sheep hearts in the presence of ACh (0.1-4.0 microM) and studied using optical mapping and bipolar recordings. Dominant frequencies (DFs) were determined in optical and electrical signals and phase movies were used to identify rotors and quantify their dynamics. DFs in both atria increased monotonically with ACh concentration until saturation, but the LA frequency predominated at all concentrations. Rotors were also seen more often in the LA, and although their life span decreased, their frequency and number of rotations increased. Patch-clamp studies demonstrated that ACh-activated potassium current (I(K,ACh)) density was greater in LA than RA sheep myocytes. Additionally, ribonuclease protection assay demonstrated that Kir3.4 and Kir3.1 mRNAs were more abundant in LA than in RA. CONCLUSIONS: A greater abundance of Kir3.x channels and higher I(K,ACh) density in LA than RA myocytes result in greater ACh-induced speeding-up of rotors in the LA than in the RA, which explains the ACh dose-dependent changes in overall AF frequency and wavelet formation. 相似文献
138.
Grey scale texture analysis of endobronchial ultrasound mini probe images for prediction of benign or malignant aetiology 下载免费PDF全文
139.
Farzad Kakaei Samad Beheshtirouy Seyed Moahammad Reza Nejatollahi Iqbal Rashidi Touraj Asvadi Afshin Habibzadeh Mohammad Oliaei-Motlagh 《Canadian journal of surgery》2015,58(6):383-388
Background
Whipple surgery (pancreaticodeudenectomy) has a high complication rate. We aimed to evaluate whether adding Braun jejunojejunostomy (side-to-side anastomosis of afferent and efferent loops distal to the gastrojejunostomy site) to a standard Whipple procedure would reduce postoperative complications.Methods
We conducted a randomized clinical trial comparing patients who underwent standard Whipple surgery (standard group) and patients who underwent standard Whipple surgery with Braun jejunojejunostomy (Braun group). Patients were followed for 1 month after the procedure and postoperative complications were recorded.Results
Our study included 30 patients: 15 in the Braun and 15 in the standard group. In the Braun group, 4 (26.7%) patients experienced 6 complications, whereas in the standard group, 7 (46.7%) patients experienced 11 complications (p = 0.14). Complications in the Braun group were gastrointestinal bleeding and wound infection (n = 1 each) and delayed gastric emptying and pulmonary infection (n = 2 each). Complications in the standard group were death, pancreatic anastomosis leak and biliary anastomosis leak (n = 1 each); gastrointestinal bleeding (n = 2); and afferent loop syndrome and delayed gastric emptying (n = 3 each). There was no significant difference between groups in the subtypes of complications.Conclusion
Our results showed that adding Braun jejunojejunostomy to standard Whipple procedure was associated with lower rates of afferent loop syndrome and delayed gastric emptying. However, more studies are needed to define the role of Braun jejunojejunostomy in this regard.Trial registration
IRCT2014020316473N1 (www.irct.ir) 相似文献140.
Hadis Sabour Abbas Norouzi Javidan Sahar Latifi Farzad Shidfar Ramin Heshmat Seyed-Hassan Emami Razavi Mohammad Reza Vafa Bagher Larijani 《The journal of spinal cord medicine》2015,38(5):599-606