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991.
992.
The external envelope glycoprotein (gp46) and transmembrane glycoprotein (gp21) of human T-cell lymphotropic virus type I (HTLV-I) were isolated from lysates of HTLV-I-infected HUT-102 cells by affinity chromatography. Fifty ml aliquots of packed HUT-102 cells were extracted with 1% Triton X-100, and lysates were treated sequentially with an affinity column containing IgG from an HTLV-I+ human subject followed by chromatography of the bound fraction over a lentil lectin column. The identity of the purified envelope proteins was confirmed with a human monoclonal antibody (0.5 alpha) to gp46 and with rabbit antisera raised to a synthetic peptide from the C-terminus of gp21. Affinity-purified envelope glycoproteins were bound to microtiter wells and used in radioimmunoassay to detect murine and human anti-envelope antibodies to gp46 and gp21 molecules.  相似文献   
993.
The effect of a sustained isometric retrusive contraction on maximum voluntary retrusive force levels was measured in normal jaw function. Surface electromyographic recordings of the suprahyoids, masseter and posterior temporalis were taken and force was measured with a force transducer. Subjects sustained isometric force at the 25, 50, 75 and 100 per cent level, and measurements made before, during and after these sustained isometric tasks. There was no change in the brief maximum voluntary contraction levels of the retruder muscles during or after such tasks, which suggests a lack of contractile or electrical failure in these muscles. Pain intolerance, rather than demonstrable neuromuscular fatigue, was the limiting factor for sustained submaximal or even maximal contraction effort.  相似文献   
994.
Carbon monoxide poisoning: an update   总被引:6,自引:0,他引:6  
  相似文献   
995.
OBJECTIVE: To measure quinolinic acid, a macrophage-derived neurotoxin, in the cerebrospinal fluid (CSF) of children after traumatic brain injury (TBI) and to correlate CSF quinolinic acid concentrations to clinically important variables. DESIGN: A prospective, observational study. SETTING: The pediatric intensive care unit in Children's Hospital of Pittsburgh, a tertiary care, university-based children's hospital. PATIENTS: Seventeen critically ill children following severe TBI (Glasgow Coma Scale score <8) whose care required the placement of an intraventricular catheter for continuous drainage of CSF. Interventions: None. MEASUREMENTS AND MAIN RESULTS: Patients ranged in age from 2 mos to 16 yrs (mean 6.0 yrs). CSF was collected immediately on placement of the ventricular catheter and daily thereafter. Quinolinic acid concentration was measured by gas chromatography/mass spectroscopy in 69 samples (4.0 +/- 0.4 [SEM] samples per patient). CSF quinolinic acid concentration progressively increased after injury (p = .034, multivariate analysis) and was increased in nonsurvivors vs. survivors (p = .002, multivariate analysis). CSF quinolinic acid concentration was not associated with age. Although overall CSF quinolinic acid concentration was not associated with shaken injury (p = .16, multivariate analysis), infants suffering with shaken infant syndrome had increased admission CSF quinolinic acid concentrations compared with children with accidental mechanisms of injury (p = .027, Mann-Whitney Rank Sum test). CONCLUSIONS: A large and progressive increase in the macrophage-derived neurotoxin quinolinic acid is seen following severe TBI in children. The increase is strongly associated with increased mortality. Increased CSF quinolinic acid concentration on admission in children with shaken infant syndrome could reflect a delay in presentation to medical attention or age-related differences in quinolinic acid production. These findings raise the possibility that quinolinic acid may play a role in secondary injury after TBI in children and suggest an interaction between inflammatory and excitotoxic mechanisms of injury following TBI.  相似文献   
996.
The use of a vacuum device as a routine procedure at the time of repeat cesarean delivery was associated with major fetal intracranial hemorrhage. In the absence of clear evidence of benefit, the routine use of vacuum extraction at the time of cesarean delivery is not justified, given its potential for serious fetal injury.  相似文献   
997.
BackgroundCompared with their ensured counterparts, uninsured adolescents and young adults (AYAs) with cancer are more likely to present with advanced disease and have poor prognoses. The Patient Protection and Affordable Care Act (ACA), enacted in 2010, provided health care coverage to millions of uninsured young adults by allowing them to remain on their parents’ insurance until age 26 years (the Dependent Care Expansion, DCE). The impact of the expansion of insurance coverage on survival outcomes for young adults with cancer has not been assessed.ParticipantsUtilizing the Surveillance, Epidemiology, and End Results database, we identified all patients aged 12-16 (younger-AYAs), 19-23 (middle-AYAs), and 26-30 (older-AYAs) who were diagnosed with cancer between 2006-2008 (pre-ACA) and 2011-2013 (post-ACA).MethodsIn this population-based cohort study, we used an accelerated failure time model to assess changes in survival rates before and after the enactment of the ACA DCE.ResultsMiddle-AYAs ages 19-23 (thus eligible to remain on their parents’ insurance) experienced significantly increased 2-year survival after the enactment of the ACA DCE (survival time ratio 1.25, 95% confidence interval: 0.75-2.43, P = .029) and that did not occur in younger-AYAs (ages 12-16). Patients with sarcoma and acute myeloid leukemia accounted for the majority of improvement in survival. Middle-AYAs of hispanic ethnicity and those with low socioeconomic status experienced trends of improved survival after the ACA DCE was enacted.ConclusionSurvival outcomes improved for young adults with cancer following the expansion of health insurance coverage. Efforts are needed to expand coverage for the millions of young adults who do not have health insurance.  相似文献   
998.
Multiple actions of interleukin 6 within a cytokine network   总被引:51,自引:0,他引:51  
  相似文献   
999.
Vascularity for healing of meniscus repairs   总被引:5,自引:0,他引:5  
Vascularity in the human meniscus is poor beyond 1-2 mm from the meniscosynovial junction, yet 22% of the tears in this series occur with a greater than or equal to 3-mm peripheral white rim. It is possible to suture these tears with the wider peripheral white rims, but healing rates are reduced because it is more difficult to obtain a satisfactory vascular supply. This article describes the history of our efforts at obtaining blood supply for healing of meniscus tears with a peripheral white rim up to 5 mm. Resection of the peripheral white rim to the vascular bed was unsatisfactory because it reduced the size of the meniscus and, by 3 years, the subsequent degenerative changes in the knee were comparable to meniscectomy. Holes made in the rim with a biopsy needle were again unsuccessful at improving healing. The present technique involves using rasps to abrade the parameniscal synovium on both the superior and inferior surface of the peripheral white rim. None of the peripheral white rim is resected. In the first series of 240 patients in whom peripheral white rim resection or the biopsy punch was used, the failure rate of meniscus healing was 22%. In a subsequent series of 68 patients (52 males, 16 females) who had 81 meniscal repairs by means of the rasp for parameniscal synovial abrasion, the failure rate was 9%. The rasp appears to be the safest and most effective method to gain vascularity for healing of meniscus repairs. It is possible to obtain healing with 5-mm peripheral white rims without resection of any portion of this rim, thus maintaining the full size of the meniscus.  相似文献   
1000.

Introduction

Duodenal neuroendocrine tumors (NETs) are rare neoplasms with poorly defined management. We sought to evaluate the outcomes of patients undergoing resection of duodenal NETs.

Methods

Using a multi-institutional database, 146 patients who underwent resection for duodenal NETs between 1993 and 2015 were identified. Data on clinicopathologic characteristics and outcomes were collected and analyzed.

Results

Local surgical resection (LR) was performed in 57 (39.0 %) patients, while 50 (34.3 %) patients underwent pancreaticoduodenectomy (PD) and 39 (26.7 %) patients an endoscopic resection (ER). Factors associated with worse RFS included advanced tumor grade and metastasis at diagnosis (both P?<?0.05) but not procedure type (P?>?0.05). Among patients who had at least one lymph node examined (n?=?85), 50 (58.8 %) had a metastatic lymph node; lymph node metastasis (P?=?0.04) and advanced tumor grade (P?=?0.04) were more common among patients with tumors >1.5 cm. Median length-of-stay was longer for PD versus LR (P?<?0.001). PD patients were at increased risk for severe postoperative complications (P?=?0.01).

Conclusion

Recurrence of duodenal NETs was dependent on tumor biology rather than procedure type. PD was associated with a longer hospital stay and higher risk of perioperative complications. For patients with tumors ≤1.5 cm, LR or ER may be appropriate with PD reserved for larger lesions and those not amenable to a more local approach.
  相似文献   
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