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1.
Quantitative diagnostic performance of myocardial perfusion SPECT with attenuation correction in women. 总被引:1,自引:0,他引:1
Arik Wolak Piotr J Slomka Mathews B Fish Santiago Lorenzo Daniel S Berman Guido Germano 《Journal of nuclear medicine》2008,49(6):915-922
Attenuation correction (AC) for myocardial perfusion SPECT (MPS) had not been evaluated separately in women despite specific considerations in this group because of breast photon attenuation. We aimed to evaluate the performance of AC in women by using automated quantitative analysis of MPS to avoid any bias. METHODS: Consecutive female patients--134 with a low likelihood (LLk) of coronary artery disease (CAD) and 114 with coronary angiography performed within less than 3 mo of MPS--who were referred for rest-stress electrocardiography-gated 99mTc-sestamibi MPS with AC were considered. Imaging data were evaluated for contour quality control. An additional 50 LLk studies in women were used to create equivalent normal limits for studies with AC and with no correction (NC). An experienced technologist unaware of the angiography and other results performed the contour quality control. All other processing was performed in a fully automated manner. Quantitative analysis was performed with the Cedars-Sinai myocardial perfusion analysis package. All automated segmental analyses were performed with the 17-segment, 5-point American Heart Association model. Summed stress scores (SSS) of > or =3 were considered abnormal. RESULTS: CAD (> or =70% stenosis) was present in 69 of 114 patients (60%). The normalcy rates were 93% for both NC and AC studies. The SSS for patients with CAD and without CAD for NC versus AC were 10.0 +/- 9.0 (mean +/- SD) versus 10.2 +/- 8.5 and 1.6 +/- 2.3 versus 1.8 +/- 2.5, respectively; P was not significant (NS) for all comparisons of NC versus AC. The SSS for LLk patients for NC versus AC were 0.51 +/- 1.0 versus 0.6 +/- 1.1, respectively; P was NS. The specificity for both NC and AC was 73%. The sensitivities for NC and AC were 80% and 81%, respectively, and the accuracies for NC and AC were 77% and 78%, respectively; P was NS for both comparisons. CONCLUSION: There are no significant diagnostic differences between automated quantitative MPS analyses performed in studies processed with and without AC in women. 相似文献
2.
The clinical features and prognosis of pseudoseizures diagnosed using video-EEG telemetry 总被引:25,自引:0,他引:25
A total of 110 patients underwent diagnostic evaluation for attacks of uncertain origin by means of video-EEG telemetry and had a diagnosis of pseudoseizures confirmed. Eighty-six patients (78%) were female, mean age of onset 25 years, and mean duration of attacks was 3 years. Many of the patients had erroneously been thought to be suffering from epilepsy. The attacks could be divided into two broad categories: attacks of collapse (one-third) and attacks with prominent motor activity (two-thirds). In some patients, the attacks were associated with incontinence and injury. The differential diagnosis and clinical features of the attacks are described. Additional psychiatric features were present in 52 (47%) patients. Follow-up (for a median 5 years; range, 1 to 14 years) showed that 40% of these patients stopped having pseudoseizures. This favorable outcome was associated with being female, leading an independent life, a formal psychological approach to therapy and counseling, and the absence of coexisting epilepsy, but not with the duration of pseudoepilepsy, prior episodes of pseudostatus, the coexistence of overt psychiatric disease, or the clinical features of the attacks. 相似文献
3.
4.
J F Walker L M Archibald S R Cherniak V G Fish 《Journal of speech and hearing research》1992,35(1):4-13
The major purposes of this study were to provide normative data on articulation rate in preschool children and to examine the influence on articulation rate of age, gender, context, and utterance length. The subjects were twenty 3-year-old children and twenty 5-year-old children, equally balanced for gender. Durational measures of utterances were analyzed in syllables and phones per second in both spontaneous and imitated speech contexts. The articulation rate of the 5-year-old subjects was significantly faster than that of the 3-year-olds. Spontaneous speech was significantly faster and more variable than imitated speech. Some gender differences were found. Measures in syllables per second and phones per second, although not always yielding identical results, were found to be highly correlated. 相似文献
5.
Unique variant of partial anomalous pulmonary venous connection with intact atrial septum 总被引:1,自引:0,他引:1
Summary Partial anomalous pulmonary venous connections (PAPVCs) are rare in association with an intact atrial septum. However, the diagnosis should be considered in patients with otherwise unexplained findings of left-to-right shunt and right heart enlargement. An unusual variant is presented, which we considered unsuitable for operative repair, based on findings at catheterization. Developmental, hemodynamic, and surgical considerations are discussed. 相似文献
6.
Escherichia coli endotoxin (ET) was administered to adult rats by continuous IV infusion from a subcutaneously implanted osmotic pump (Alzet). Cardiac output and regional blood flow were determined by the radiolabeled microsphere method after 6 and 30 hr of ET or saline infusion. Cardiac output (CO) of ET rats was not different from time-matched controls, whereas arterial pressure was 13% lower after 30 hr of infusion. After both 6 and 30 hr of ET, pancreatic blood flow and percentage of cardiac output were lower than in controls. Estimated portal venous flow was decreased at each time point, and an increased hepatic arterial flow (significant after 30 hr) resulted in an unchanged total hepatic blood flow. Blood flow to most other tissues, including epididymal fat, muscle, kidneys, adrenals, and gastrointestinal tract, was similar between treatments. Maintenance of blood flow to metabolically important tissues indicates that the previously reported alterations in in vitro cellular metabolism are not due to tissue hypoperfusion. Earlier observations of in vitro myocardial dysfunction, coexistent with the significant impairment in pancreatic flow, raise the possibility that release of a myocardial depressant factor occurs not only in profound shock but also under less severe conditions of sepsis and endotoxemia. 相似文献
7.
8.
OBJECTIVE--To develop a noninvasive clinical predictive model for acute congestive heart failure (CHF) in a frail elderly cohort using bedside clinical assessment (medical history and physical examination) and venous atrial natriuretic peptide (ANP) levels. DESIGN--One-year prospective blinded cohort study. SETTING--Life care facility. PARTICIPANTS--Three hundred thirty-one frail, elderly volunteers free of acute illness at study entry (mean +/- SD age, 88 +/- 7 years; 23% male, 77% female). MAIN OUTCOME MEASURE--Clinical episodes of CHF with confirmation of acute pulmonary edema by chest roentgenogram. RESULTS--Fifteen percent of the elderly cohort developed at least one episode of CHF during the 1-year follow-up period. Those developing CHF had significantly higher mean +/- SE ANP values at study entry: 493 +/- 55 vs 207 +/- 15 pmol/L. The risk for development of CHF rose progressively with increasing ANP levels at study entry. In multivariate analysis, only two independent variables significantly predicted CHF: ANP value greater than 200 pmol/L (adjusted odds ratio [OR], 7.9; 95% confidence interval [CI], 3.2 to 19.2) and history of CHF in the previous year (adjusted OR, 7.0; 95% CI, 2.9 to 17). Stratifying the cohort by these two variables results in three CHF risk groups: 55% of the population at 3% annual risk of CHF, 37% of the population at 20% to 24% annual risk of CHF, and 8% of the population at 66% annual risk of CHF. CONCLUSIONS--This simple clinical prediction model identifies elderly subjects at risk for CHF and allows appropriate focusing of medical resources for prevention, early detection, and treatment of this highly morbid clinical syndrome. 相似文献
9.
Dr. Douglas N. Fish Pharm. D. Dr. Stephen C. Piscitelli Pharm. D. Dr. Larry H. Danziger Pharm. D. 《Pharmacotherapy》1995,15(3):279-291
The incidence of emergent resistance and clinical factors affecting its development were evaluated by retrospective review of 173 studies encompassing over 14,000 patients. Eight antibiotic classes and 225 individual treatment regimens were evaluated. Emergent resistance occurred among 4.0% of all organisms and 5.6% of all infections treated. It appeared to be significantly more frequent with penicillin and aminoglycoside monotherapy, with significantly lower rates associated with imipenem-cilastatin, aztreonam, and combination therapy. Clinical failure also appeared to be significantly more likely to occur after emergence of resistance among organisms treated with fluoroquinolones or aminoglycosides. Infections associated with higher resistance rates were cystic fibrosis, osteomyelitis, and lower respiratory tract infections. Resistance was most common in patients in intensive care units or receiving mechanical ventilation. It was also significantly frequent among studies performed in university or teaching hospitals. Organisms associated with high resistance rates were Pseudomonas aeruginosa, Serratia, Enterobacter, and Acinetobacter sp. Factors such as infection type, underlying diseases, type of institution, and specific pathogens warrant consideration when examining emergent resistance. 相似文献
10.
Dr. Douglas N. Fish Pharm. D. Ms. Jacquelyn L. Bainbridge B.S. Pharm. Dr. Charles A. Peloquin Pharm. D. 《Pharmacotherapy》1995,15(2):236-245
Continuous arteriovenous hemodiafiltration (CAVHD) is being used increasingly in critically ill patients with acute renal failure (ARF). We prospectively evaluated extracorporeal and total systemic clearances (ClCAVHD and Cls) of ciprofloxacin during CAVHD in four patients with severe ARF to assess the adequacy of drug dosing. Ciprofloxacin serum and ultrafiltrate concentrations were measured by high-performance liquid chromatography. The ClCAVHD accounted for approximately 5.9% (range 2.8–11.6%) of Cls of ciprofloxacin. However, large variability in serum concentrations was observed with the normally recommended dose of 400 mg/day, and doses of up to 800 mg/day were required to maintain concentrations suitable for treatment of serious infections. High daily doses of ciprofloxacin required in these patients are likely related to altered pharmacokinetics in serious illness as well as to the increased extracorporeal clearance during CAVHD. Clinical studies to define appropriate dosing recommendations for ciprofloxacin during CAVHD are necessary to guide clinicians in optimum drug use. 相似文献