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101.
E. Palenque E. Amor J. C. Bernaldo de Quiros 《European journal of clinical microbiology & infectious diseases》1987,6(2):191-192
The diagnostic yields of bronchial washings, bronchial brushings and lung biopsy specimens were compared in 50 patients with positive
Mycobacterium tuberculosis
cultures. The number of positive results obtained with cultures of bronchial brushings was significantly higher than that with bronchial washings (p < 0.001). The histological study of biopsy lung material improved the rate of immediate or rapid diagnosis of tuberculosis (p<0.001). 相似文献
102.
The use of Mixture Toxicity Indices (MTI's) is one of the more attractive approaches for describing and predicting the effects of mixtures of toxicants. For an MTI to apply to all possible mixtures of the compounds in question, it must summarize information from a model describing all possible responses of interest. A method of obtaining MTI's from response surface equations or from tolerance models similar to the toxic units model is presented. Methods of calculating several MTI's with desirable properties from multivariable probit response surfaces are demonstrated. 相似文献
103.
Mário Martins Oliveira Nogueira da Silva Ana Teresa Timóteo Joana Feliciano Lídia de Sousa Sofia Santos Fernando Marques Rui Ferreira 《Revista portuguesa de cardiologia》2007,26(7-8):691-702
Atrial electrical remodeling plays a part in recurrence of atrial fibrillation (AF). It has been related to an increase in heterogeneity of atrial refractoriness that facilitates the occurrence of multiple reentry wavelets and vulnerability to AF. AIM: To examine the relationship between dispersion of atrial refractoriness (Disp_A) and vulnerability to AF induction (A_Vuln) in patients with clinical paroxysmal AF (PAF). METHODS: Thirty-six patients (22 male; age 55+/-13 years) with > or =1 year of history of PAF (no underlying structural heart disease--n=20, systemic hypertension--n=14, mitral valve prolapse--n=1, surgically corrected pulmonary stenosis--n=1), underwent electrophysiological study (EPS) while off medication. The atrial effective refractory period (AERP) was assessed at five different sites--high (HRA) and low (LRA) lateral right atrium, high interatrial septum (IAS), proximal (pCS) and distal (dCS) coronary sinus--during a cycle length of 600 ms. AERP was taken as the longest S1-S2 interval that failed to initiate a propagation response. Disp_A was calculated as the difference between the longest and shortest AERP. A_Vuln was defined as the ability to induce AF with 1-2 extrastimuli or with incremental atrial pacing (600-300 ms) from the HRA or dCS. The EPS included analysis of focal electrical activity based on the presence of supraventricular ectopic beats (spontaneous or with provocative maneuvers). The patients were divided into group A--AF inducible (n=25) and group B--AF not inducible (n=11). Disp_A was analyzed to determine any association with A_Vuln. Disp_A and A_Vuln were also examined in those patients with documented repetitive focal activity. Logistic regression was used to determine any association of the following variables with A_Vuln: age, systemic hypertension, left ventricular hypertrophy, left atrial size, left ventricular function, duration of PAF, documented atrial flutter/tachycardia and Disp_A. RESULTS: There were no significant differences between the groups with regard to clinical characteristics and echocardiographic data. AF was inducible in 71% of the patients and noninducible in 29%. Group A had greater Disp_A compared to group B (105+/-78 ms vs. 49+/-20 ms; p=0.01). Disp_A was >40 ms in 50% of the patients without A_Vuln and in 91% of those with A_Vuln (p=0.05). Focal activity was demonstrated in 14 cases (39%), 57% of them with A_Vuln. Disp_A was 56+/-23 ms in this group and 92+/-78 ms in the others (p=0.07). Using logistic regression, the only predictor of A_Vuln was Disp_A (p=0.05). CONCLUSION: In patients with paroxysmal AF, Disp_A is a major determinant of A_Vuln. Nevertheless, the degree of nonuniformity of AERP appears to be less important as an electrophysiological substrate for AF due to focal activation. 相似文献
104.
BACKGROUND: We reviewed the publication record of all protocols submitted to the Capital District Health Authority Research Ethics Board (REB) in Halifax, Nova Scotia, for the period 1995-1996. Because of a heightened awareness of the issue, we hypothesized that there would be less publication bias (a failure to report negative results) and a higher publication rate from completed studies, than previously reported. METHODS: Closed studies were identified from the REB database. Publications were identified by the investigators, requests from sponsors, and a literature review. For each publication, we identified authors, title, journal, number of subjects enrolled, and whether or not the publication was a report of a randomized clinical trial. Comparisons were done using a Student's t test, the Chi-square statistic, or Fisher's exact test as appropriate. RESULTS: From the database of closed studies, 106 remained unpublished, while completed investigations resulted in 84 publications (44% publication rate). The median time to publication was 32.5 months. Publication of statistically significant results occurred in 71/84 trials. Publication of protocols submitted by departments ranged from 91% (anesthesia; 10/11) to 25% [nursing; 2/8 (P<0.05)]. Trials investigating new drugs in Phase 3 or 4 studies were more likely to be published than trials investigating agents in Phase 1 or 2 (P<0.05), and were less likely to be published if sponsored by a pharmaceutical company (P<0.05). CONCLUSIONS: Publication bias continues to be a problem, particularly for early phase investigative studies. Our results suggest that a different approach is required to reduce publication bias. The role that REBs and peer-reviewed journals might play requires further exploration. 相似文献
105.
Rigatelli Gianluca; Cardaioli Paolo; Giordan Massimo; Roncon Loris 《European heart journal》2007,28(1):51
A 65-year-old hypertensive man with shortness of breath andatypical thoracic pain underwent coronary angiography for 相似文献
106.
Berman Brian MD PhD Flores Javier MD † Pariser David MD ‡ Pariser Robert MD ‡ Araujo Tami de MD Ramirez Claudia C. MD 《Dermatologic surgery》2005,31(2):135-138
BACKGROUND Dermatologic procedures often cause some degree of pain. A self-warming patch containing lidocaine and tetracaine (L/T) was developed to provide topical local anesthesia prior to painful procedures.
OBJECTIVES To evaluate the safety and efficacy of a self-warming L/T patch to provide anesthesia in adult patients undergoing minor dermatologic procedures.
METHODS An active or placebo study drug was placed on adults 30 minutes prior to minor dermatologic surgical procedures in a prospectively randomized, double-blinded manner. Subcutaneous lidocaine injection was available during the procedure as a rescue medication if requested by the subject. Immediately following the procedure, the subjects, the investigator, and an independent observer rated pain intensity and adverse events were recorded.
RESULTS Patient-reported pain intensity was significantly lower in the L/T patch group ( p < .001 ). Investigators and an independent observer rated the pain in the L/T patch group to be less than in the placebo patch group ( p = .004 and p < .001 , respectively). Forty-nine percent of patients in the placebo group required rescue subcutaneous lidocaine compared with 22% in the L/T patch study group ( p = .008 ). One patient in the L/T patch group reported a transient moderate burning sensation.
CONCLUSION The self-warming L/T patch was effective in providing clinically useful local anesthesia for minor dermatologic procedures in adult patients.
ZARS, INC., PROVIDED SUPPORT VIA A SPONSORED RESEARCH GRANT TO THE UNIVERSITY OF MIAMI. 相似文献
OBJECTIVES To evaluate the safety and efficacy of a self-warming L/T patch to provide anesthesia in adult patients undergoing minor dermatologic procedures.
METHODS An active or placebo study drug was placed on adults 30 minutes prior to minor dermatologic surgical procedures in a prospectively randomized, double-blinded manner. Subcutaneous lidocaine injection was available during the procedure as a rescue medication if requested by the subject. Immediately following the procedure, the subjects, the investigator, and an independent observer rated pain intensity and adverse events were recorded.
RESULTS Patient-reported pain intensity was significantly lower in the L/T patch group ( p < .001 ). Investigators and an independent observer rated the pain in the L/T patch group to be less than in the placebo patch group ( p = .004 and p < .001 , respectively). Forty-nine percent of patients in the placebo group required rescue subcutaneous lidocaine compared with 22% in the L/T patch study group ( p = .008 ). One patient in the L/T patch group reported a transient moderate burning sensation.
CONCLUSION The self-warming L/T patch was effective in providing clinically useful local anesthesia for minor dermatologic procedures in adult patients.
ZARS, INC., PROVIDED SUPPORT VIA A SPONSORED RESEARCH GRANT TO THE UNIVERSITY OF MIAMI. 相似文献
107.
L Savelli P de Iaco T Ghi L Bovicelli F Rosati B Cacciatore 《Ultrasound in obstetrics & gynecology》2004,23(3):284-288
OBJECTIVE: To describe the sonographic features of peritoneal pseudocysts (PPCs) in order to determine the particular aspects that distinguish them from true ovarian cysts. METHODS: Thirty-one women with PPCs were investigated using transvaginal sonography immediately before surgery. The diameters of the cysts were measured, and the shape, margins, content, location, presence of septa and echogenic portions were analyzed. RESULTS: The PPCs were monolateral in 20 (65%) and bilateral in 11 (35%) women. A well-defined cystic structure was found in only six (19%) women, while in the other 25 (81%) women the PPCs showed blurred, undefined margins and a bizarre morphology, giving them a star-like tubular or lumpy shape. The ipsilateral ovary was identified in 26 (84%) cases either external to the cyst or entrapped within it like a 'spider in a web'. Septa were present in 25 (81%) cases and were often mobile, resembling a 'flapping sail' when touched by the endovaginal probe. CONCLUSION: Despite having a gross morphology resembling that of a true ovarian cyst, PPCs present some characteristic sonographic findings that allow a correct differential diagnosis in the vast majority of cases. 相似文献
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