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111.
High and low spatial frequency information in visual images is processed by distinct neural channels. Using event-related functional magnetic resonance imaging (fMRI) in humans, we show dissociable roles of such visual channels for processing faces and emotional fearful expressions. Neural responses in fusiform cortex, and effects of repeating the same face identity upon fusiform activity, were greater with intact or high-spatial-frequency face stimuli than with low-frequency faces, regardless of emotional expression. In contrast, amygdala responses to fearful expressions were greater for intact or low-frequency faces than for high-frequency faces. An activation of pulvinar and superior colliculus by fearful expressions occurred specifically with low-frequency faces, suggesting that these subcortical pathways may provide coarse fear-related inputs to the amygdala.  相似文献   
112.
Normal development of the human lower urinary tract was studied between the 14th and 20th week of gestation using 3 modes of fixation. Fixation by direct distension provides a high degree of reproducibility of parameters used to study the growth of the fetal bladder. Using this method, fetuses ranging from 12 to 21 weeks gestation were studied. Results obtained demonstrate that the length of the bladder, the inter-ureteric distance, and the distance between the apex of the trigone and the distal tip of the urethra occur in a linear mode. Furthermore, the rate of growth of the male urethra was evidently higher when compared to that of the female from the 12th week of gestation. Data from this work can be used for a more accurate assessment of cases with abnormal lower urinary tract development.  相似文献   
113.
Normal development of the human lower urinary tract was studied between the 14th and 20th week of gestation using 3 modes of fixation. Fixation by direct distension provides a high degree of reproducibility of parameters used to study the growth of the fetal bladder. Using this method, fetuses ranging from 12 to 21 weeks gestation were studied. Results obtained demonstrate that the length of the bladder, the inter-ureteric distance, and the distance between the apex of the trigone and the distal tip of the urethra occur in a linear mode. Furthermore, the rate of growth of the male urethra was evidently higher when compared to that of the female from the 12th week of gestation. Data from this work can be used for a more accurate assessment of cases with abnormal lower urinary tract development.© Willey-Liss, Inc.  相似文献   
114.
STUDY OBJECTIVE: Female hormones, specifically progesterone, that peak in the luteal phase may play a significant role in protecting premenopausal women from sleep-disordered breathing. The influence of female hormones on upper airway resistance during sleep was investigated during the follicular and luteal phases of normal menstrual cycles. SETTING: Hospital-based sleep laboratory. DESIGN AND PARTICIPANTS: Healthy women with verified ovulatory cycles and without sleep complaints were recruited into the study. Sleep and upper airway resistance data (mean +/- SD) were collected on 2 nights from 11 women (21-49 years of age [28 +/- 9 years], body mass index of 22.8 +/- 3.6 kg/m2), once during the follicular phase (day 6-11) and once in the luteal phase (day 19-23) in random order. MEASUREMENTS AND RESULTS: Nasal resistance, standardized to a flow rate of 0.3 L/second, measured using posterior active rhinomanometry immediately prior to the sleep study, did not differ between the 2 phases. The respiratory disturbance index tended to be higher in the follicular phase than in the luteal phase and was above 5 per hour for 3 women in the follicular phase. Upper airway resistance, controlled for flow rate and body position, was calculated for 50 random breaths during wakefulness, stage 1, stage 2, slow-wave, and rapid eye movement sleep. During wake and stage 2 sleep, upper airway resistance was significantly higher in the follicular phase than in the luteal phase, as was the overall upper airway resistance combined for wake and across all sleep stages. Combining data from the 2 nights, compared to wake, upper airway resistance increased in stage 2, slow-wave, and rapid eye movement sleep. CONCLUSIONS: Within the menstrual cycle, upper airway resistance is lower in the luteal compared with the follicular phase.  相似文献   
115.
Noncontact low‐frequency ultrasound (NLFU) is used to treat various types of chronic wounds including venous, diabetic, and pressure ulcers. The objective for this substudy of the IN BALANCE RCT VLU trial was to characterize and compare the NLFU treatment group and patients receiving standard of care (SOC) with respect to the effect of the assigned study treatment on content/quantity of inflammatory cytokines and fibrinogen as well as bacteria. Higher mean wound area reduction was observed in the NLFU treatment group (67.0%) compared to the SOC group (41.6%, p < 0.05). Hypertension, diabetes type II, coronary artery disease, and anemia were identified as the most common comorbidities of the Chronic venous leg ulcer (CVLU) patients included in the study. Pseudomonas, Corynebacterium, and unclassified Enterobacteriaceae were dominant in the highest number of samples. Anaerococcus, Peptoniphilus, and Finegoldia, had the highest median proportion in the samples overall. Peptoniphilus abundance decreased more in the NLFU treatment group relative to SOC; similar trends were observed for Anaerococcus and Finegoldia. Progression of mediators like TNF‐alpha, IL‐1beta, IL‐6, IL‐8, and IL‐10 as well as PF4, TGF‐beta, and fibrinogen was monitored and trends for several of the mediators were identified. Fibrinogen amounts were significantly reduced over time in the NLFU treatment group (p < 0.05). IL‐8 levels declined in wound fluid from NLFU responders as well as SOC responders. Bacterial load (total bacterial abundance) determined local parameters of ulcer inflammation. If a bioburden of ≥ 10E5 was found compared to < 10E5, levels of IL‐1beta, IL‐8, and TNF‐alpha were significantly higher. In conclusion, NLFU treatment is an effective adjuvant tool for CVLU therapy. This study demonstrates that it improves wound healing by equally inhibiting abundant levels of pro‐inflammatory cytokines as well as by reducing the overall bacterial burden.  相似文献   
116.
Wounds that exhibit delayed healing add extraordinary clinical, economic, and personal burdens to patients, as well as to increasing financial costs to health systems. New interventions designed to ease such burdens for patients with cancer, renal, or ophthalmologic conditions are often cleared for approval by the U.S. Food and Drug Administration (FDA) using multiple endpoints but the requirement of complete healing as a primary endpoint for wound products impedes FDA clearance of interventions that can provide other clinical or patient‐centered benefits for persons with wounds. A multidisciplinary group of wound experts undertook an initiative, in collaboration with the FDA, to identify and content validate supporting FDA criteria for qualifying wound endpoints relevant to clinical practice (CP) and patient‐centered outcomes (PCO) as primary outcomes in clinical trials. As part of the initiative, a research study was conducted involving 628 multidisciplinary expert wound clinicians and researchers from 4 different groups: the interdisciplinary core advisory team; attendees of the Spring 2015 Symposium on Advanced Wound Care (SAWC); clinicians employed by a national network of specialty clinics focused on comprehensive wound care; and Association for the Advancement of Wound Care (AAWC) and Wound Healing Society (WHS) members who had not previously completed the survey. The online survey assessed 28 literature‐based wound care endpoints for their relevance and importance to clinical practice and clinical research. Fifteen of the endpoints were evaluated for their relevance to improving quality of life. Twenty‐two endpoints had content validity indexes (CVI) ≥ 0.75, and 15 were selected as meriting potential inclusion as additional endpoints for FDA approval of future wound care interventions. This study represents an important first step in identifying and validating new measurable wound care endpoints for clinical research and practice and for regulatory evaluation.  相似文献   
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119.
Current treatment options for systemic lupus erythaematosus (SLE) are diverse and poorly defined, and aggressive therapy can be associated with serious toxicity and tolerability issues. There is, therefore, a need for new and improved treatments to be studied thoroughly in well-designed controlled trials. B Cell dysfunction has emerged as a key pathophysiological component of SLE and is a prime target for the development of new agents for a wide range of lupus severity, including advanced disease. Although many current drugs appear to modify B cell function, the advent of new, targeted therapies offers the hope of improved efficacy and a better long-term tolerability profile.  相似文献   
120.

Background

Studies addressing patients with type 2 myocardial infarction and myocardial injury, including the impact of using high-sensitivity (hs) cardiac troponin (cTn) assays on their incidence are needed.

Methods

Ours is a prospective, observational US cohort study. Consecutive emergency department patients with serial cTnI measurements were studied. Outcomes included 180-day mortality and major adverse cardiac events, including 2-year follow-up for those with myonecrosis.

Results

Among 1640 patients, using a contemporary cTnI assay, 30% (n = 497) had ≥1 cTnI >99th percentile, with 4.7% (n = 77), 8.5% (n = 140), and 17% (n = 280) classified as type 1 myocardial infarction, type 2 myocardial infarction, and myocardial injury, respectively. Compared with patients without myonecrosis, 180-day mortality was higher for type 2 myocardial infarction (4% vs 13%, P < .0001) (adjusted hazard ratio 2.7; 95% confidence interval, 1.6-4.8; P = .0005) and myocardial injury (4% vs 11%, P < .0001) (adjusted hazard ratio 1.8; 95% confidence interval, 1.1-3.0; P = .02), both with mortality >20% at 2 years. Predictors of 2-year mortality for type 2 myocardial infarction included age, congestive heart failure, and beta-blockers. Relative to the contemporary cTnI assay, hs-cTnI had less myonecrosis (30% vs 26%, P = .003) and acute myocardial infarction (13.2% vs 10.8%, P = .032), including fewer type 2 myocardial infarctions (8.5% vs 6.3, P = .01), with no difference in myocardial injury (17% vs 15%, P = .1).

Conclusions

cTnI increases are encountered in approximately a third of patients, the majority due to nonatherothrombotic conditions. Compared with patients without myonecrosis, type 2 myocardial infarction and myocardial injury have worse short-term outcomes, with mortality rates >20% at 2 years. hs-cTnI assay does not lead to more myocardial injury or infarction.  相似文献   
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