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991.
Objective. To report unique methods of treatment and review catheter‐based intervention for occluded modified Blalock–Taussig shunts (BTS). Methods. Case reports and articles involving children undergoing catheter‐based treatment for occluded modified BTS were reviewed. Results. Literature review detailed 38 patients in whom occluded modified BTS were treated with 39 catheter‐based interventions. Thrombolytics alone were delivered by catheter in 13 cases. Balloon angioplasty was performed in 23 cases, 5 with stent implantation. Both thrombolytic delivery and angioplasty were performed in 3 cases, 2 with stent implantation. Intervention was initially successful at re‐establishing modified BTS patency in 35/39 (90%) of cases. Patency could not be established in 2 patients who then proceeded to the operating for surgical shunt revision. Two deaths occurred during the procedures. Three cases at Emory University demonstrate uncommon or unique instances of catheter‐based intervention: (1) declotting of a shunt in a patient supported by extracorporeal membrane oxygenation (ECMO); (2) declotting of a shunt via a right axillary arterial approach; and (3) declotting of a shunt using a carotid arterial (ECMO) cannula for percutaneous access. Conclusions. The use of catheter‐based techniques for the treatment of BTS occlusion is highly successful, and potentially avoids high‐risk re‐operative intervention. ECMO can provide for a stable patient during the procedure. Hopefully, with improved technology and innovative procedures, more children in the future with BTS occlusion can be served by successful percutaneous intervention.  相似文献   
992.
Endogenous plasma prolactin and baseline corticosterone concentrations were measured in Dark-eyed Juncos (Junco hyemalis, n=27) photostimulated into migratory condition to look at how these hormones may be linked to the development of migratory condition. In addition to the commonly used assay for corticosterone, a recombinant-derived European starling prolactin assay validated for Dark-eyed juncos was used to measure endogenous prolactin in order to detect small but significant changes in plasma prolactin levels. In response to transfer from short (10.5L:13.5D) to long (18L:6D) days, the birds increased in body mass, fat score, daily food intake, and nocturnal migratory locomotor activity (Zugunruhe). On short-days, both hormones were low (corticosterone mean=2.89ng/mL+/-0.48 SE; prolactin mean=6.43ng/mL+/-1.31 SE). But, within 14 days of photostimulation both hormones increased significantly (Day 14: corticosterone mean=5.71ng/mL+/-0.77 SE; prolactin mean=19.67ng/mL+/-2.81 SE), rising further by Day 48 (corticosterone mean=8.41ng/mL+/-0.72; prolactin mean=112.67ng/mL+/-9.18 SE). On Day 48, birds with the most fat (fat score=3) had significantly higher corticosterone levels than those with less fat (fat score=2). This pattern, albeit not statistically significant, was similar for prolactin. These results illustrate that, independent of the seasonal peak in prolactin associated with the onset of photorefractoriness, plasma prolactin levels can rise, in concert with corticosterone, as birds come into spring migratory condition, providing some support for earlier hypotheses that these two hormones play an integral role in the development of migratory condition. Whether similar changes in plasma prolactin occur with respect to autumn migration, as does baseline corticosterone, has yet to be determined.  相似文献   
993.
BACKGROUND: Follicular bronchiolitis is a histopathologic finding that occurs in diverse clinical contexts. The current study was conducted to characterize clinico-radiologic features, and assess outcomes associated with follicular bronchiolitis. SUBJECTS AND METHODS: Twelve subjects with follicular bronchiolitis on lung biopsy were seen over a 9-year period, between 1996 and 2005. Medical records, biopsy and radiographic findings, and details of outcome at the time of last follow-up were recorded. RESULTS: The study population included 4 men and 8 women; the median age at diagnosis was 54 years (range, 33-81 years). Four patients had underlying systemic diseases that included: 2 with common variable immunodeficiency, 1 Sj?gren's syndrome and 1 undifferentiated connective tissue disease. The diagnosis was obtained by surgical lung biopsy in all cases. Follicular bronchiolitis was the major histologic pattern in 9 patients; organizing pneumonia, nonspecific interstitial pneumonia and usual interstitial pneumonia was seen in 1 patient each with follicular bronchiolitis being an associated secondary histopathologic component. Computed tomographic findings included reticular opacities, small nodules and ground-glass opacities. Clinical course was characterized by relative stability with partial response to immunosuppressive agents. During a median follow-up period of 47 months, only one death occurred--out of 9 patients where the outcome information was available--and was unrelated to lung disease. CONCLUSIONS: The histologic lesion of follicular bronchiolitis may be seen as the predominant finding or a relatively minor feature in interstitial pneumonias. The clinical course and prognosis for most patients with follicular bronchiolitis is relatively good, and progressive lung disease is uncommon.  相似文献   
994.
995.
996.
CONTEXT: Daily PTH administration increases bone mineral density (BMD) and reduces fracture risk. However, cost and compliance significantly limit clinical use. OBJECTIVE: Our objective was to determine whether less frequent PTH administration increases lumbar spine BMD. PARTICIPANTS, DESIGN, AND SETTING: Fifty postmenopausal women ages 45-70 yr with femoral neck BMD T-score between -1.0 and -2.0 participated in a double-blind, randomized, placebo-controlled trial at St. Joseph Hospital, Bangor, ME. INTERVENTION: Subjects received sc injections of daily PTH(1-84) (100 mug) or placebo for 1 month, followed by weekly injections (PTH or placebo) for 11 months. OUTCOMES: Change in lumbar spine dual-energy x-ray absorptiometry areal BMD (primary) was assessed. Secondary outcomes included volumetric BMD at spine and hip by quantitative computed tomography, trabecular bone microarchitecture by magnetic resonance imaging of distal radius, and biochemical bone turnover markers. RESULTS: At 12 months, lumbar spine areal BMD increased 2.1% in PTH-treated women compared with placebo (P = 0.03). Vertebral trabecular volumetric BMD increased 3.8% in PTH-treated women compared with placebo group (P = 0.08). PTH-treated women also had higher distal radial trabecular bone volume, number, and thickness compared with placebo-treated women (P < 0.04). After 1 month of daily PTH, N-terminal propeptide of type I collagen (P1NP) was markedly increased compared with placebo (P < 0 .0001), and a difference persisted, although lessened, throughout the study. Bone resorption indices were unchanged in PTH-treated women and were reduced in the placebo group. CONCLUSION: Once-weekly PTH after 1 month of daily treatment increases spine BMD, radial trabecular bone, and bone formation markers in postmenopausal women. These results suggest that less frequent alternatives to daily PTH dosing for 2 yr could be effective. Additional studies are required to define the optimal frequency of PTH administration.  相似文献   
997.
Objective: To assess whether patients can weigh risk comparisons involving mortality and quality of life in an understandable manner based on their willingness to accept risks of complications. Design: Cross-sectional survey of patients. Setting: University-based Department of Veterans Affairs Medical Center. Participants: 230 men patients seen in a general medicine clinic. Measurements: Two survival graphs were used. Each graph contained survival curves for two alternative unidentified treatments for an unidentified medical condition. Graph 2 contained one curve that had a life expectancy that was 14% higher than the life expectancy of the corresponding curve in graph 1. Respondents were randomly assigned one of the two graphs and were asked to indicate which treatment they preferred and what risk of a change in their quality of life (urinary incontinence or impotence) they were willing to accept to achieve longer survival. Patients were also asked whether they had a history of urinary incontinence or impotence. Results and conclusions: Patients tended to be unwilling to accept worse quality of life to achieve increased survival over time. For both curve comparisons, significantly more (p<0.01) patients accepted a treatment associated with higher mortality to avoid a 100% chance of incontinence than to avoid a 100% chance of impotence. Of the 75% (172/230) of patients reporting willingness to accept risk of either urinary incontinence or total impotence or both, 62% reported having at least some symptoms related to urinary incontinence or impotence. Of the 58 patients not willing to accept the complication risks, only 11% reported a history of urinary incontinence or impotence. The results show that patients are able to make distinctions about severity of morbidity, men are less willing to accept the risk of urinary incontinence than that of total impotence, and men patients who are symptomatic with urinary incontinence or impotence are more willing to accept the risks of treatment than are asymptomatic patients. Received from the Department of Veterans Affairs Medical Center, Oregon Health Sciences University, Portland, Oregon.  相似文献   
998.
Monitoring recovery from diaphragm paralysis with ultrasound   总被引:1,自引:0,他引:1  
BACKGROUND: Diaphragmatic paralysis is an uncommon, yet underdiagnosed cause of dyspnea. Data regarding the time course and potential for recovery has come from a few small case series. The methods that have been traditionally employed to diagnose diaphragmatic weakness or paralysis are either invasive or limited in sensitivity and specificity. A new technique utilizing two-dimensional, B-mode ultrasound (US) measurements of diaphragm muscle thickening during inspiration (Deltatdi%) has been validated in the diagnosis of diaphragm paralysis (DP). The purpose of this study was to assess whether serial US evaluation might be utilized to monitor the potential recovery of diaphragm function. METHODS: Twenty-one consecutive patients with clinically suspected DP were referred to the pulmonary physiology laboratory. Sixteen patients were found to have DP by US (unilateral, 10 patients; bilateral, 6 patients). Subjects were followed up for up to 60 months. On initial and subsequent visits, Deltatdi% was measured by US. Additional measurements included upright and supine vital capacity (VC), maximal inspiratory pressure (Pimax), and maximal expiratory pressure. RESULTS: Eleven of 16 patients functionally recovered from DP. The mean (+/- SD) recovery time was 14.9 +/- 6.1 months. No diaphragm thickening was noted in those patients who did not recover. Positive correlations were found between improvement in Deltatdi% and interval changes in VC, Pimax, and end-expiratory measurements of diaphragm thickness. CONCLUSIONS: US may be used to assess for potential functional recovery from diaphragm weakness or DP. As in previous series, recovery occurs in a substantial number of individuals, but recovery time may be prolonged.  相似文献   
999.
BACKGROUND: Acute asthma often requires expensive emergency department visits and hospitalizations, especially among economically disadvantaged inner-city adults. However, few studies have examined approaches for improving acute asthma care in this population. METHODS: We conducted a cohort study involving patients who were discharged from a public hospital emergency department following acute asthma care between March 31, 1997, and August 5, 1999, to identify processes of care effective for improving peak expiratory flow rate at a 2- to 3-week follow-up. Adult patients who met the predetermined criteria for asthma, who underwent a baseline peak expiratory flow rate reading, and who did not have concurrent acute sinusitis or pneumonia were eligible (N = 448). Of the 365 patients enrolled in the study, 309 (84.7%) completed it. We used a multiple linear regression analysis adjusted for patient risk to assess the association between acute asthma care processes derived from the National Asthma Education Prevention Program guidelines (inhaled beta2-agonists, inhaled corticosteroids, systemic corticosteroids, asthma care follow-up, and patient asthma education) and percentage peak expiratory flow rate change at follow-up. RESULTS: Systemic corticosteroids had a significant effect for increasing percentage peak expiratory flow rate change at the 2- to 3-week follow-up for all asthma exacerbation severity levels (beta = 26.1; 95% confidence interval, 1.8-50.5; P =.04) and severity levels specified by the National Asthma Education Prevention Program guidelines (beta = 31.6; 95% confidence interval, 8.1-55.1; P =.01). CONCLUSION: Outpatient systemic corticosteroids were effective for improving lung function 2 to 3 weeks after acute asthma care, and their use should reduce asthma-related morbidity, especially among economically disadvantaged inner-city adults.  相似文献   
1000.

Objectives

The aim of this study was to assess the implications of concomitant tricuspid regurgitation (TR) in patients undergoing valve-in-valve (VIV) transcatheter aortic valve replacement.

Background

Patients undergoing VIV transcatheter aortic valve replacement with concomitant TR may have worse outcomes, and optimal management remains undetermined.

Methods

The multicenter PARTNER 2 (Placement of Aortic Transcatheter Valves) VIV trial enrolled patients with symptomatic degenerated surgical aortic bioprostheses who were at high risk for reoperation. Outcomes were assessed between patients with mild or no TR versus moderate or severe TR.

Results

A total of 237 patients underwent VIV procedures (mean age 78.7 ± 10.8 years, mean Society of Thoracic Surgeons score 9.1 ± 4.8%). In this cohort, 162 patients (68.4%) had mild or no TR, and 75 patients (31.6%) had moderate or severe TR. Although there was no difference in New York Heart Association functional class III or IV symptomatic status (89.3% vs. 91.4%; p = 0.62) or moderate or severe right ventricular dysfunction (9.4% vs. 16.9%; p = 0.11), patients with moderate or severe TR were more likely to be at high surgical risk, with a Society of Thoracic Surgeons score of >8 (62.7% vs 46.9%; p = 0.02). There was no difference in a composite endpoint of death and rehospitalization between moderate or severe TR and mild or no TR, either at 30 days (10.7% vs. 9.9%; p = 0.85) or at 1-year follow-up (24.1% vs. 23.2%; p = 0.80). There was a significant reduction in overall moderate or severe TR from baseline at 30 days (31.1% vs. 21.1%; p = 0.002), which was sustained at 1-year follow-up (38.0% vs. 22.8%; p = 0.004).

Conclusions

Despite higher predicted surgical risk, the presence of TR was not a predictor of long-term outcomes. Importantly, there was significant reduction in TR severity at both short- and long-term follow-up. In selected patients undergoing VIV transcatheter aortic valve replacement, it may be appropriate to conservatively manage concomitant TR.  相似文献   
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