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91.
Adenosine was administered to test the hypothesis that it would maximize preexcitation and facilitate noninvasive localization of accessory pathways in 22 patients with suspected accessory pathway-mediated tachycardias. Twelve-lead electrocardiograms and 2-dimensional echocardiograms were recorded at baseline and during adenosine-augmented ventricular preexcitation to localize the accessory pathway. Phase analysis was performed on digitized 4-chamber and short-axis views using a first harmonic Fourier transformation. At baseline, 15 patients had manifest preexcitation. In 14 of these patients (93.3%), preexcitation became more prominent after adenosine. Four patients without preexcitation at baseline clearly had it after adenosine. In patients who had preexcitation in response to adenosine, the electrocardiogram correctly identified the accessory pathway locations in 18 of 19 patients at a regional level and was incorrect in 1 of 19 patients. Echocardiographic phase analysis correctly identified the accessory pathway location in all 17 patients, who had technically adequate studies, at a regional level. In conclusion, administration of adenosine accentuates preexcitation, allowing for more accurate electrocardiographic and echocardiographic accessory pathway localization.  相似文献   
92.
PURPOSE: The aim of this study was to (1) determine whether nonimaging variables add to the diagnostic information available from exercise thallium-201 images for the detection of multivessel coronary artery disease; and (2) to develop a model based on the exercise thallium-201 stress test to predict the presence of multivessel disease. PATIENTS AND METHODS: The study populations included 383 patients referred to the University of Virginia and 325 patients referred to the Massachusetts General Hospital for evaluation of chest pain. All patients underwent both cardiac catheterization and exercise thallium-201 stress testing between 1978 and 1981. RESULTS: In the University of Virginia cohort, at each level of thallium-201 abnormality (no defects, one defect, more than one defect), ST depression and patient age added significantly in the detection of multivessel disease. Logistic regression analysis using data from these patients identified three independent predictors of multivessel disease: initial thallium-201 defects, ST depression, and age. A model was developed to predict multivessel disease based on these variables. As might be expected, the risk of multivessel disease predicted by the model was similar to that actually observed in the University of Virginia population. More importantly, however, the model was accurate in predicting the occurrence of multivessel disease in the unrelated population studied at the Massachusetts General Hospital. CONCLUSION: It is, therefore, concluded that (1) nonimaging variables (age and exercise-induced ST depression) add independent information to thallium-201 imaging data in the detection of multivessel disease; and (2) a model has been developed based on the exercise thallium-201 stress test that can accurately predict the probability of multivessel disease in other populations.  相似文献   
93.
In a 2-year study of false-positive anti-HIV-1 tests in blood donors at Manchester and Lancaster Blood Banks, the reactions associated with a HIV-infected cell lysate antigen were compared with those using recombinant-antigen-based tests. In year 1 (cell lysate test) at Manchester BTS 0.21% of 119.178 donations were repeatedly reactive, compared with 0.53% of 119,004 donations in year 2 (recombinant antigen). Reactive sera were tested at Manchester PHL by three different immunoassays. Referred specimens were classified as anti-HIV positive (95-100% reactive in all the assays), equivocal or negative (negative results in all three immunoassays). Two donors were confirmed to be anti-HIV positive over the 2-year period. Most sera were negative by confirmatory immunoassays in years 1 and 2. In year 1, a study of 60 referred sera with sex- and age-matched controls showed high correlation between a reactive anti-HIV-1 screening test and indeterminate anti-HIV-1 patterns on Western blot showing reactions with HIV gag-coded proteins. In year 2, less than 10% of referred sera were reactive by Western blot, and there was no correlation between a reactive screening anti-HIV test, the strength of signal in the test or a reactive Western blot. Follow-up showed that donors whose sera were reactive in years 1 and 2 by the anti-HIV-1 screening test formed almost two different populations. Four donors with equivocal anti-HIV-1 confirmatory tests had anti-HIV 'envelope' reactions.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
94.
Severe aortic stenosis (AS) and heart failure (HF) represent an important and high-risk group of patients who are often referred for transcatheter aortic valve replacement (TAVR) due to high risk for surgical intervention. Thus far, randomized controlled trials have shown comparable outcomes between TAVR and surgical aortic valve replacement in patients with severe AS and heart failure with reduced ejection fraction. In the current review, we will discuss (1) the pathophysiology of HF in patients with severe AS, (2) role of imaging modalities in management, (3) role of biomarkers of HF on prognosis, (4) impact of other valvular heart diseases, (5) evidence from the contemporary trials on the role of TAVR in patients with severe AS and HF, and (6) future directions and research.  相似文献   
95.
96.
One of the main objectives of root canal treatment is to alleviate the pain associated with irreversibly inflamed pulps. However, some patients may have moderate to severe pain following treatment. The aim of this study was to compare and assess the effect of ketorolac tromethamine on substance P expression in the pulp and periapical tissues when used as a root canal irrigant for single‐visit root canal treatment in teeth with irreversible pulpitis. Thirty‐six patients were randomly allotted to three irrigant groups – saline (n = 14), 3% sodium hypochlorite (n = 11) and ketorolac tromethamine (n = 11). Pulp blood samples (S1) were collected on gaining access to the pulp, and periapical blood samples (S2) were collected after root canal preparation. Quantification of substance P was done by ELISA test. The ketorolac tromethamine group had greater reduction in substance P expression (S2). Post‐operative pain levels were not significantly influenced by the different root canal irrigants.  相似文献   
97.
Avulsion of permanent teeth is one of the most serious dental injuries. Prompt and correct emergency management is essential for attaining the best outcome after this injury. The International Association of Dental Traumatology (IADT) has developed these Guidelines as a consensus statement after a comprehensive review of the dental literature and working group discussions. It represents the current best evidence and practice based on that literature search and expert opinions. Experienced researchers and clinicians from various specialties and the general dentistry community were included in the working group. In cases where the published data did not appear conclusive, recommendations were based on consensus opinions or majority decisions of the working group. They were then reviewed and approved by the members of the IADT Board of Directors. The purpose of these Guidelines is to provide clinicians with the most widely accepted and scientifically plausible approaches for the immediate or urgent care of avulsed permanent teeth. The IADT does not, and cannot, guarantee favorable outcomes from adherence to the Guidelines. However, the IADT believes that their application can maximize the probability of favorable outcomes.  相似文献   
98.
Traumatic dental injuries (TDIs) occur most frequently in children and young adults. Older adults also suffer TDIs but at significantly lower rates than individuals in the younger cohorts. Luxation injuries are the most common TDIs in the primary dentition, whereas crown fractures are more commonly reported for the permanent teeth. Proper diagnosis, treatment planning and follow up are very important to assure a favorable outcome. These updates of the International Association of Dental Traumatology's (IADT) Guidelines include a comprehensive review of the current dental literature using EMBASE, MEDLINE, PUBMED, Scopus, and Cochrane Databases for Systematic Reviews searches from 1996 to 2019 and a search of the journal Dental Traumatology from 2000 to 2019. The goal of these guidelines is to provide information for the immediate or urgent care of TDIs. It is understood that some follow‐up treatment may require secondary and tertiary interventions involving dental and medical specialists with experience in dental trauma. As with previous guidelines, the current working group included experienced investigators and clinicians from various dental specialties and general practice. The current revision represents the best evidence based on the available literature and expert opinions. In cases where the published data were not conclusive, recommendations were based on the consensus opinions of the working group. They were then reviewed and approved by the members of the IADT Board of Directors. It is understood that guidelines are to be applied using careful evaluation of the specific clinical circumstances, the clinician's judgment, and the patient's characteristics, including the probability of compliance, finances and a clear understanding of the immediate and long‐term outcomes of the various treatment options vs non‐treatment. The IADT does not, and cannot, guarantee favorable outcomes from adherence to the Guidelines. However, the IADT believes that their application can maximize the probability of favorable outcomes.  相似文献   
99.
100.
OBJECTIVE: To assess the effect of a physician and pharmacist teamwork approach to uncontrolled hypertension in a medical resident teaching clinic, for patients who failed to meet the recommended goals of the fifth Joint National Commission on Detection, Evaluation and Treatment of High Blood Pressure. HYPOTHESIS: Physician and pharmacist teamwork can improve the rate of meeting national blood pressure goals in patients with previously uncontrolled hypertension. DESIGN: A single-blinded randomized controlled trial lasting 6 months. SETTING: A primary care outpatient teaching clinic. PATIENTS: A sample of 95 adult hypertensive patients who failed to meet national blood pressure goals based on three consecutive visits over a 6-month period. INTERVENTION: Patients were randomly assigned to a control arm of standard medical care or to an intervention arm in which a physician and pharmacist worked together as a team. MAIN RESULTS: At study completion, the percentage of patients achieving national goals due to intervention was more than double the percentage in the control arm (55% vs 20%, p < .001). Systolic blood pressure declined 23 mm Hg in the intervention arm versus 11 mm Hg in the control arm (p < .01). Diastolic blood pressure declined 14 and 3 mm Hg in the intervention and control arms, respectively (p < .001). The intervention worked equally as well in men and women and demonstrated noticeable promise in a minority of mixed-ancestry Hawaiians in whom hypertension is of special concern. CONCLUSIONS: Patients who fail to achieve national blood pressure goals under standard outpatient medical care may benefit from a program that includes a physician and pharmacist teamwork approach. The views expressed in this article are those of the authors and do not reflect the official policy or position of the Queen’s Medical Center. This work was supported by a grant from the Queen’s Medical Center, Honolulu, Hawaii and by a Research Centers in Minorities Institutions Award (P20 RR 11091) from the National Institutes of Health.  相似文献   
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