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OBJECTIVE: To examine the reliability of a functional weight-bearing measure of hindfoot alignment, the standing tibiocalcaneal angle (STCA), and to compare the relative reliabilities of goniometrically and visually estimated STCAs. DESIGN: Prospective blinded comparison. SETTING: Sports medicine center. PARTICIPANTS: Eighteen asymptomatic volunteer subjects (10 men, 8 women; age range, 22-41y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Two experienced examiners completed 2 blinded goniometric STCA and 2 blinded visual STCA measurements on each subject's right and left ankles in random order. RESULTS: Quantitative visual and goniometric STCAs were similar (visual mean range, 5.61 degrees -6.50 degrees valgus vs goniometric mean range, 5.50 degrees -6.94 degrees valgus), and both measurements exhibited good to excellent intrarater reliabilities (intraclass correlation coefficient [ICC] range, .80-.94; 95% prediction limits, 1.51 degrees -2.06 degrees ). Interrater ICCs were only fair for both measurement methods (.50-.75; 95% prediction limits, 2.2 degrees -4.1 degrees ). In terms of relative reliability, the visual STCA and goniometric STCA exhibited good to excellent agreement (ICC range, .64-.95). CONCLUSIONS: The STCA as described herein exhibited acceptable intrarater reliability for clinical use but may not be acceptably reliable between experienced examiners. The visual and goniometric STCA measurements were quantitatively similar and exhibited similar reliability. Using either method, changes of up to 2 degrees over time may be attributable to measurement error. Clinicians may consider using either STCA measurement in evaluating patients with lower-limb injuries or during screening of high-risk populations.  相似文献   
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From a study of nitric oxide (NO) output in the nose and sinuses it seems that: (i) the results obtained regarding the regulation of NO output in the nose do not necessarily apply to the sinuses; (ii) the results obtained for one group of sinuses may not apply to another; and (iii) NO output in the sinuses does not behave as one would expect if it serves to protect against infection.A pilot study was undertaken in one subject to determine whether the control of NO output in the nose differs from that in the sinuses.NO output was measured by aspirating different gaseous concentrations of oxygen (and/or carbon dioxide) through the nasal airways or punctured maxillary and frontal sinuses before and after i.v. administration of L-arginine (20 mg/kg).In the absence of gaseous oxygen in the nose or maxillary antrum, the effect of L-arginine on NO output was the same as that in the presence of oxygen. In the frontal sinus, the effect of L-arginine on NO output was blocked by the absence of gaseous oxygen. NO output in the nose and frontal sinus showed similar changes after either i.v. administration of L-arginine or removal of oxygen from the air. NO output in the maxillary antrum was virtually unaffected by either procedure. NO output in the nose was largely unaffected by the gaseous carbon dioxide content but that in the frontal and maxillary sinuses was profoundly inhibited by it. In both sinuses, suppression of NO output by carbon dioxide was countered by oxygen. Alterations in the oxygen or carbon dioxide content of the maxillary antrum did not alter NO output in the frontal sinus, or vice versa. After i.v. infusion of L-arginine, nasal NO output remained elevated for >1 h.  相似文献   
44.

Background  

The adiposity rebound is the second rise in body mass index that occurs between 3 and 7 years. An early age at adiposity rebound is known to be a risk factor for later obesity. The aim here is to clarify the connection between the age at rebound and the corresponding pattern of body mass index change, in centile terms, so as to better understand its ability to predict later fatness.  相似文献   
45.
BACKGROUND: The neurochemical and biological effects of antidepressant medications have become better defined over the last decade. When the anti-depressant bupropion was introduced in the United States in 1989, the specific pharmacologic basis of its clinical effects was uncertain. Research conducted over the past decade has significantly advanced the understanding of the neuropharmacology of bupropion and has demonstrated a novel mechanism of antidepressant activity. This article discusses the mechanism of action of bupropion and relates the drug's neuropharmacologic effects to its clinical efficacy and tolerability profiles. DATA SOURCES: Data were obtained via the MEDLINE database in an English-language search spanning the period 1965 to May 2002 and using the search terms bupropion, bupropion SR, and antidepressants, as well as from the manufacturer's bupropion databases. CONCLUSIONS: The preclinical and clinical data show that bupropion acts via dual inhibition of norepinephrine and dopamine reuptake and is devoid of clinically significant serotonergic effects or direct effects on postsynaptic receptors. Dual norepinephrine and dopamine reuptake inhibition is associated with a unique clinical profile. Bupropion has demonstrated efficacy comparable to that of other antidepressants. However, because bupropion is a selective norepinephrine and dopamine reuptake inhibitor with no serotonergic activity, common antidepressant-associated side effects, such as sexual dysfunction, weight gain, and sedation, are not associated with bupropion therapy.  相似文献   
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P G Djupesland  W Qian  J S Haight 《Chest》2001,120(5):1645-1650
STUDY OBJECTIVES: The present study introduces a method that has been developed to improve the remote collection and transportation of gas samples from the nose and lungs. DESIGN: Assessment of agreement between two methods of clinical measurements. SETTING: Noninvasive exhaled gas measurement at a respiratory research laboratory. PARTICIPANTS: Ten nonsmoking adult volunteers (median age, 44 years; age range, 33 to 53 years; men, 6; women, 4) were recruited. MEASUREMENTS AND RESULTS: Exhaled nitric oxide (ENO) and nasal nitric oxide (NNO) outputs were measured directly (on-line) and remotely (off-line). With the velum closed, lung air was exhaled at fixed flows (ie, 6, 8, and 10 L/min) (ENO) or room-air was aspirated through the nose in series at one fixed flow (ie, 5 to 8 L/min) (NNO). The off-line nitric oxide (NO) measurements were achieved by a gas collection tube system, which consisted of a flow control unit, a tube reservoir with one-way valves at both ends, and an interrupter valve allowing the trapping of gas inside the tube and eliminating the inclusion of "dead space." After clamping, the reservoir may store and transport the gas samples for delayed analysis. The coefficient of variation of three consecutive NO measurements was < 3% for both on-line and off-line ENO and NNO. The correlations between on-line and off-line measurements in both ENO and NNO outputs were high (r = 0.99; R(2) = 0.99), and, unlike previous studies using bag-collection, the ENO outputs for on-line and off-line measurements were in good agreement (Bland-Altman test) at all flows tested. CONCLUSIONS: The tube gas collection system eliminates the dead space and contamination during the gas sampling and permits the cost-effective and reliable off-line collection of both nasal and exhaled gas samples.  相似文献   
49.
OBJECTIVE: To determine whether there is a difference between on-pump cardiopulmonary bypass (CABG) and off-pump coronary artery bypass grafting (OPCAB) without heparin reversal with regard to bleeding, transfusion requirements, and incidence of surgical re-exploration of the mediastinum. DESIGN: Retrospective chart review. SETTING: A large academic medical center. PARTICIPANTS: Two hundred adult patients undergoing cardiac surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: One hundred CABG patients were compared with 100 OPCAB patients. Statistical significance was measured with P values of 相似文献   
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