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81.
This article examines the effect of a bout of unloaded leg cycling on the soleus H-reflex and modified Ashworth scale (MAS) in 6 individuals with multiple sclerosis (MS) who had spasticity of the leg muscles and were currently taking anti-spastic medications. H-reflex and MAS data were collected before and 10, 30, and 60 min after 20 min of unloaded leg cycling and a control condition. The unloaded leg cycling resulted in concomitant reductions in soleus H-reflex and MAS scores compared with the control condition. This provides a basis for incorporating exercise along with anti-spastic medications into a multifaceted plan for spasticity management in individuals with MS.  相似文献   
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83.
The G protein-coupled thyrotropin (TSH)-releasing hormone (TRH) receptor forms homodimers. Regulated receptor dimerization increases TRH-induced receptor endocytosis. These studies test whether dimerization increases receptor phosphorylation, which could potentiate internalization. Phosphorylation at residues 355-365, which is critical for internalization, was measured with a highly selective phospho-site-specific antibody. Two strategies were used to drive receptor dimerization. Dimerization of a TRH receptor-FK506-binding protein (FKBP) fusion protein was stimulated by a dimeric FKBP ligand. The chemical dimerizer caused a large increase in TRH-dependent phosphorylation within 1 min, whereas a monomeric FKBP ligand had no effect. The dimerizer did not alter phoshorylation of receptors lacking the FKBP domain. Dimerization of receptors containing an N-terminal HA epitope also was induced with anti-HA antibody. Anti-HA IgG strongly increased TRH-induced phosphorylation, whereas monomeric Fab fragments had no effect. Anti-HA antibody did not alter phosphorylation in receptors lacking an HA tag. Furthermore, two phosphorylation-defective TRH receptors functionally complemented one another and permitted phosphorylation. Receptors with a D71A mutation in the second transmembrane domain do not signal, whereas receptors with four Ala mutations in the 355-365 region signal normally but lack phosphorylation sites. When D71A- and 4Ala-TRH receptors were expressed alone, neither underwent TRH-dependent phosphorylation. When they were expressed together, D71A receptor was phosphorylated by G protein-coupled receptor kinases in response to TRH. These results suggest that the TRH receptor is phosphorylated preferentially when it is in dimers or when preexisting receptor dimers are driven into microaggregates. Increased receptor phosphorylation may amplify desensitization.  相似文献   
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85.

Background

Dedicated prospective studies investigating high-definition intravascular ultrasound (HD-IVUS)-guided primary percutaneous coronary intervention (PCI) are lacking. The aim of this study was to qualify and quantify culprit lesion plaque characteristics and thrombus using HD-IVUS in patients presenting with ST-segment elevation myocardial infarction (STEMI).

Methods

The SPECTRUM study is a prospective, single-center, observational cohort study investigating the impact of HD-IVUS-guided primary PCI in 200 STEMI patients (NCT05007535). The first 100 study patients with a de novo culprit lesion and a per-protocol mandated preintervention pullback directly after vessel wiring were subject to a predefined imaging analysis. Culprit lesion plaque characteristics and different thrombus types were assessed. An IVUS-derived thrombus score, including a 1-point adjudication for a long total thrombus length, long occlusive thrombus length, and large maximum thrombus angle, was developed to differentiate between low (0–1 points) and high (2–3 points) thrombus burden. Optimal cut-off values were obtained using receiver operating characteristic curves.

Results

The mean age was 63.5 (±12.1) years and 69 (69.0%) patients were male. The median culprit lesion length was 33.5 (22.8–38.9) mm. Plaque rupture and convex calcium were appreciated in 48 (48.0%) and 10 (10.0%) patients, respectively. Thrombus was observed in 91 (91.0%) patients (acute thrombus 3.3%; subacute thrombus 100.0%; organized thrombus 22.0%). High IVUS-derived thrombus burden was present in 37/91 (40.7%) patients and was associated with higher rates of impaired final thrombolysis in myocardial infarction flow (grade 0–2) (27.0% vs. 1.9%, p < 0.001).

Conclusions

HD-IVUS in patients presenting with STEMI allows detailed culprit lesion plaque characterization and thrombus grading that may guide tailored PCI.  相似文献   
86.
Purpose: To describe the thin-slice magnetic resonance imaging features of vascular compressive oculomotor nerve paresis.Methods: We performed thin-slice (2 mm thick) magnetic resonance imaging of the brainstem in a 74-year-old woman with right partial oculomotor nerve paresis using spoiled gradient recalled acquisition in the steady state.Results: Thin-slice magnetic resonance images disclosed that the right oculomotor nerve was compressed and dislocated superiorly and laterally by the tortuous basilar artery. No other abnormalities were observed.Conclusion: This is the first case report of vascular compressive oculomotor nerve paresis disclosed by thin-slice magnetic resonance imaging.  相似文献   
87.
Kenney  RT; Malech  HL; Epstein  ND; Roberts  RL; Leto  TL 《Blood》1993,82(12):3739-3744
The genetic defect in the p67phox-deficient form of chronic granulomatous disease (CGD) follows an autosomal recessive pattern of inheritance. When genomic DNA from normal individuals is digested with HindIII and probed with p67phox cDNA an allelic restriction fragment length polymorphism (RFLP) of 4.0 kb or 2.3 kb is detected. We cloned and characterized the p67phox gene using the cDNA and sequenced the exon/intron boundaries, mapping 16 exons on the 40-kb gene. The polymorphic region was then sequenced to identify the inheritance pattern of amniocentesis-derived fetal cells by genomic amplification. The proband, a 9-year-old female patient with p67phox-deficient CGD, and her phenotypically normal mother are homozygous for the RFLP marker, whereas the father and two brothers are heterozygous. The fetus was shown to be heterozygous as well, showing it had inherited at least one normal p67phox gene from the father and that it was predicted to have a normal phenotype. Cord blood samples at birth showed normal oxidative function. Amplification allows rapid detection of the inheritance pattern for fetal diagnosis in informative families. We report the genomic structure of p67phox and an amplification-based method for detection of the marker on chromosome 1q25, used here for prenatal diagnosis of CGD.  相似文献   
88.
The Financial Impact of Ambulance Diversions and Patient Elopements   总被引:1,自引:1,他引:0  
Objectives
Admission process delays and other throughput inefficiencies are a leading cause of emergency department (ED) overcrowding, ambulance diversion, and patient elopements. Hospital capacity constraints reduce the number of treatment beds available to provide revenue-generating patient services. The objective of this study was to develop a practical method for quantifying the revenues that are potentially lost as a result of patient elopements and ambulance diversion.
Methods
Historical data from 62,588 patient visits to the ED of a 450-bed nonprofit community teaching hospital in central Pennsylvania between July 2004 and June 2005 were used to estimate the value of potential patient visits foregone as a result of ambulance diversion and patients leaving the ED without treatment.
Results
The study hospital may have lost $3,881,506 in net revenue as a result of ambulance diversions and patient elopements from the ED during a 12-month period.
Conclusions
Significant revenue may be foregone as a result of throughput delays that prevent the ED from utilizing its existing bed capacity for additional patient visits.  相似文献   
89.
90.
This study identified a sample of young African-American men and women classified as having multiple sex partners or one sex partner. Of the 149 men, 71 (47%) were classified as having multiple sex partners and 78 (53%) as having one sex partner. Of the 165 women, 29 (19%) were classified as having multiple sex partners and 126 (81%) as having one sex partner. Results indicated that the groups did not differ in their knowledge about acquired immunodeficiency syndrome (AIDS). However, attitudes about condom use differed significantly by gender (P less than .01) and by multiple sex status (P less than .001). Angry reactions regarding the negotiation of condom use occurred more with men than with women (P less than .05). Men and members of the multiple sex partners group tended to engage in more risky sexual behavior. These two groups also had a significantly (P less than .001) higher incidence of gonorrhea. While the multiple sex partners group had significantly more smokers (P less than .01), drinkers (P less than .01), and crack users (P less than .05), men were significantly higher consumers of marijuana (P less than .001) and alcohol (P less than .01). Overall, the results indicate that African Americans are knowledgeable about AIDS, but there appears to be a gap between knowledge and risky sexual behaviors. Prospective studies are needed to clarify the factors that determine the relationship (or lack of) between knowledge and risky sexual behaviors. Without such studies, a major part of the foundation that is needed for the development of sensitive and effective AIDS prevention programs for African Americans will be missing.  相似文献   
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